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Abstract

The research focused on the glucosinolate (GLS) breakdown products formed during the fermentation of cabbage. A relationship between the contents of degradation products in fermented cabbage and native GLS in raw cabbage was investigated. The effect of fermented cabbage storage on the contents of individual compounds was also assayed. Ascorbigen formed from one of the degradation products of glucobrassicin (indole GLS) was found to be a dominating compound in fermented cabbage. Irrespective of the time of fermented cabbage storage, the content of ascorbigen reached approximately 14 micromol/100 g. Neither the content of isothiocyanates, the major degradation products of aliphatic GLS, nor that of cyanides exceeded 2.5 microM. Storage of cabbage caused periodical increases and decreases in the contents of cyanides and consequent declines in the contents of isothiocyanates. The highest relative contents (expressed as a percentage of the native GLS content) of degradation products--ranging from >70 to 96%--were reported for the products of glucoraphanin degradation, whereas the lowest-- <5% --were reported for the products of sinigrin degradation.

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... In general, fermentation reduces the GS content significantly. In sauerkraut production and storage, there was no GS detected in the product, irrespective of cultivation season on the cabbage, type of fermentation, and concentration of salt [81][82][83]. The breakdown products of GS were detected, such as ITCs, cyanides, indole-3-carbinol, indole-3-acetonitrile, and ascorbigen [77,[81][82][83]. ...
... In sauerkraut production and storage, there was no GS detected in the product, irrespective of cultivation season on the cabbage, type of fermentation, and concentration of salt [81][82][83]. The breakdown products of GS were detected, such as ITCs, cyanides, indole-3-carbinol, indole-3-acetonitrile, and ascorbigen [77,[81][82][83]. It is suspected that the content of the degradation products is not only influenced by the content of the native GS in raw cabbage, but also by to physicochemical properties, such as volatility, stability, and reactivity in an acidic environment, and microbiological stability [81]. ...
... The breakdown products of GS were detected, such as ITCs, cyanides, indole-3-carbinol, indole-3-acetonitrile, and ascorbigen [77,[81][82][83]. It is suspected that the content of the degradation products is not only influenced by the content of the native GS in raw cabbage, but also by to physicochemical properties, such as volatility, stability, and reactivity in an acidic environment, and microbiological stability [81]. Nevertheless, further studies are needed to explain the underlying mechanisms of GS changes during fermentation. ...
Chapter
The healthiness of a vegetable cannot solely be inferred from the amount of health-promoting compounds in the raw materials. Brassica vegetables, for example, are consumed mostly after processing to improve palatability and to extend the shelf life. However, processing also results to various changes in the content of glucosinolates which intakes are associated with a reduced risk of several cancers. The large variety in cooking practices and processing methods affect the glucosinolate content in the vegetables, particularly due to processes that allow for enzymatic hydrolysis and thermal degradation of glucosinolates, and leaching of the bioactive components. Knowledge on the effect of preparation and processing of Brassica vegetables is important to evaluate the healthiness of the consumed product and to investigate mechanisms to retain high glucosinolate levels at the stage of consumption and to increase the intake of health-protective compounds by the consumer. By using a mechanistic approach, the fate of glucosinolates during different processing and preparation methods and conditions can be explained. Boiling and blanching reduce the glucosinolate content significantly particularly because of the mechanisms of leaching following cell lysis and diffusion, and partly due to thermal and enzymatic degradation. Steaming, microwave processing, and stir frying either retain or only slightly reduce the glucosinolate content due to low degrees of leaching. These methods can enhance the accessibility of glucosinolates from the plant tissue. Fermentation reduces the glucosinolate content considerably, the underlying mechanisms are not yet completely clear, but enzymatic breakdown seems to play an important role. Studying the changes of glucosinolates during processing by a mechanistic approach is shown to be valuable to redesign the processing and to reformulate the product for improving health benefits of these compounds.
... However, withering by microwave for 2 min at 900 W inactivated myrosinase completely and produced sayur asin with a sinigrin concentration of 11.4 µmol/10 g dry matter after 7 days of fermentation. This high power-short time pretreatment the concentration of GLSs in sauerkraut [10,11] and radish kimchi [12]. ...
... Accordingly, previous studies reported that fermentation can significantly reduce the amount of GLSs in vegetables [9][10][11]36]. During sauerkraut production, Tolonen et al. [9] observed a very low quantity of 4-methoxy-glucobrassicin, while others reported traces or even no detectable GLSs in the fermented product [10,11]. ...
... Accordingly, previous studies reported that fermentation can significantly reduce the amount of GLSs in vegetables [9][10][11]36]. During sauerkraut production, Tolonen et al. [9] observed a very low quantity of 4-methoxy-glucobrassicin, while others reported traces or even no detectable GLSs in the fermented product [10,11]. Kim and Rhee [12] also reported a 25 % loss of total GLSs in radish (Raphanus sativus L.) compared to the total GLSs in raw radish on the third day of radish kimchi fermentation. ...
Article
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Fermentation can reduce the concentration of health-promoting glucosinolates in Brassica vegetables. The endogenous enzyme myrosinase is hypothesised to mainly responsible for the degradation of glucosinolates during fermentation. In order to retain glucosinolates in the final fermented product, the role of myrosinase activity during the production of sayur asin was investigated. Sayur asin is a traditionally fermented product of Indian mustard (Brassica juncea) commonly consumed in Indonesia. It is prepared by a spontaneous fermentation of withered (sundried) B. juncea leaves. The leaves of B. juncea contain a substantial amount of the aliphatic glucosinolate sinigrin. Three withering methods were investigated to obtain B. juncea leaves with different myrosinase activities prior to fermentation. Results show that withering by oven at 35 degrees C for 2.5 h and by microwave at 180 W for 4.5 min reduced myrosinase activity by 84 and 74 %, respectively. Subsequently, sinigrin was not detectable in the leaves after 24 h of incubation in the fermentation medium. However, withering by microwave for 2 min at 900 W inactivated myrosinase completely and produced sayur asin with a sinigrin concentration of 11.4 ae mol/10 g dry matter after 7 days of fermentation. This high power-short time pretreatment of B. juncea leaves contributes to the production of sayur asin containing significant levels of health-promoting glucosinolate. In this study, the effect of myrosinase activity during Brassica fermentation was quantified, and optimised production methods were investigated to retain glucosinolate in the final product.
... Fermentation is one of the methods to prepare Brassica vegetables, e.g. sauerkraut (Ciska and Pathak, 2004;Uva et al. 2006). However, fermentation commonly leads to GLSs loss in the product (Daxenbichler et al. 1980;Ciska and Pathak, 2004;Martinez-Villaluenga et al. 2009). ...
... sauerkraut (Ciska and Pathak, 2004;Uva et al. 2006). However, fermentation commonly leads to GLSs loss in the product (Daxenbichler et al. 1980;Ciska and Pathak, 2004;Martinez-Villaluenga et al. 2009). To our knowledge, there is no study on the GLSs behaviour along the sayur asin production. ...
... After 71 h of fer mentation the cabbage still contained 35% of total GLSs before fermentation (Sarvan et al. 2013). The contents of GLS der ived products depend on the fer mentation conditions as well as the concentrations of GLS of the raw material (Ciska and Pathak, 2004). Previous studies reported GLS changes during fermentation based on the changes of identified breakdown products, e.g. ...
Article
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Glucosinolates (GLSs), health promoting compounds commonly found in Brassica vegetables, were studied during sayur asin fermentation made from Indian mustard (B. juncea). The current preliminary study aims to investigate the changes of glucosinolates content during 3 and 7 days of fermentation in two different media, i.e. coconut water and tajin liquor, and salt concentrations of 2.5 and 10%. The glucosinolates were analysed by HPLC after sample extraction in hot methanol followed by purification and de-sulphation. Results show that sinigrin was the most dominant glucosinolate among others, i.e. gluconapin, glucobrassicin, 4-hydroxy-glucobrassicin, 4-methoxy-glucobrassicin, and neo glucobrassicin, accounting for about 1000 and 4000 µmol/10 g dw in raw Indian mustard. Unfortunately, fermentation has substantially reduced the glucosinolates content in sayur asin. After 3 days of fermentation the sinigrin content was reduced by 95% as compared to that in the raw vegetable. The indole GLSs 4-methoxy-glucobrassicin and neo-glucobrassicin concentration decreased to 80-90% of the fresh materials. However, the decreasing mechanisms as well as factors contributing to the decrease of the glucosinolates could not be explained yet.
... Ciska and Pathak [131] reported that glucobrassicin and sinigrin were the most abundant glucosinolates in the shredded cabbage used for fermentation. Ascorbigen, indole-3-carbinol, and indole-3-acetonitrile were identified as degradation products of the former, while allyl isothiocyanate, allyl cyanide, and 1-cyano-2,3-epithiopropane were identified as degradation products of the latter. ...
... Iberin, iberin nitrile, allyl isothiocyanate, sulforaphane, and allyl cyanide were detected, with the latter being the most abundant, ranging from 65 to 75 µmol/100 g DM. Ascorbigen has been reported as the most abundant glucosinolate degradation product in sauerkraut [126,128,131,133]. Ciska and Pathak [131] reported that ascorbigen concentration could be as high as 14 µmol/100 g. ...
... Ascorbigen has been reported as the most abundant glucosinolate degradation product in sauerkraut [126,128,131,133]. Ciska and Pathak [131] reported that ascorbigen concentration could be as high as 14 µmol/100 g. Palani et al. [126] quantified ascorbigen at the end of fermentation at 13 µmol/100 g FW. ...
Article
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Consumption of lactic acid fermented fruits and vegetables has been correlated with a series of health benefits. Some of them have been attributed to the probiotic potential of lactic acid microbiota, while others to its metabolic potential and the production of bioactive compounds. The factors that affect the latter have been in the epicenter of intensive research over the last decade. The production of bioactive peptides, vitamins (especially of the B-complex), gamma-aminobutyric acid, as well as phenolic and organosulfur compounds during lactic acid fermentation of fruits and vegetables has attracted specific attention. On the other hand, the production of biogenic amines has also been intensively studied due to the adverse health effects caused by their consumption. The data that are currently available indicate that the production of these compounds is a strain-dependent characteristic that may also be affected by the raw materials used as well as the fermentation conditions. The aim of the present review paper is to collect all data referring to the production of the aforementioned compounds and to present and discuss them in a concise and comprehensive way.
... Several studies have been conducted on the composition of GLS and their breakdown products in cabbage during fermentation and in the final product Ciska & Pathak, 2004;Harbaum-Piayda et al., 2016;Martinez-Villaluenga et al., 2009;Palani et al., 2016;Peñas et al., 2013;Tolonen et al., 2002). All of these analyses were conducted in the drained sauerkraut or sauerkraut homogenised with a brine. ...
... Tolonen et al. (2004) suggested that applying different bacterial cultures may exert diversified myrosinase-like activity and directly affects the formation of degradation products of GLS. High stability of the glucobrassicin breakdown products during storage was also reported in our previous study on sauerkraut (Ciska & Pathak, 2004). In contrast, a gradual decrease in ascorbigen content during storage was reported by Peñas et al. (2013). ...
... Breakdown products of aliphatic GLS in the sauerkraut obtained through spontaneous fermentation were the subject of our previous studies Ciska & Pathak, 2004), as well as the subject of studies conducted by other researchers Peñas, Martínez-Villaluenga, Pihlava, & Frias, 2015;Peñas et al., 2013;Peñas, Pihlava, Vidal-Valverde, & Frias, 2012;Tolonen et al., 2002). Similar to our findings regarding the stability of isothiocyanates and cyanides in sauerkraut during storage were reported previously (Ciska & Pathak, 2004). ...
Article
Sauerkraut juice has not gained much scientific attention to date. Therefore, this study aimed to track changes in glucosinolates (GLS) during fermentation of white cabbage and the formation of corresponding breakdown products in sauerkraut and sauerkraut juice separately and to evaluate their stability during prolonged storage of the final products. The results obtained indicate that both sauerkraut and sauerkraut juice are a good source of bioactive compounds: ascorbigen and isothiocyanates. The stability of individual compounds during storage varied, and the absolute content of phytochemicals depended on the content of native GLS in the raw material and its bacterial composition. The dominant compound was ascorbigen, stable in acidic pH in both sauerkraut and sauerkraut juice, even after prolonged storage. Sauerkraut juice was also found as a rich source of bioactive isothiocyanates. One 250 mL glass of sauerkraut juice (after two weeks) can deliver approx. 75 μmol of bioactive ascorbien and isothiocyanates, hence it can be considered as functional food, delivering beneficial health effects.
... The first month of storage did not lead to large losses of ABG (retention percentage of 92%), but losses of about 17% and 31%, respectively, were observed during the second and the third storage months. Our results differ from those reported by Ciska and Pathak (2004) who did not observe changes in ABG content during conventional storage of sauerkraut at 5 C for 17 weeks. These differences could be attributed to the different O 2 concentration present in the vessels used during storage. ...
... Megaton, since sinigrin is the major GLS compound present in this cultivar (Peñas, Frias, Martínez-Villaluenga, & Vidal-Valverde, 2011). All these GLS derivatives were previously identified in spontaneously fermented cabbages (Ciska & Pathak, 2004;Tolonen et al., 2002) although the proportion between the GLS breakdown products reported by these authors was different. These differences can be attributed to the variation in the GLS composition of the cabbages used in each study, which is dependent on the cultivar. ...
... These reductions are larger than those noted in the present study in stored sauerkrauts, but the results reported by these authors are not directly comparable with our results since the composition of the vegetable matrix differs. The concentration of GLS hydrolysis compounds found in this work in conventionally stored sauerkrauts was considerably higher than those reported by Ciska and Pathak (2004) in spontaneously obtained sauerkrauts stored at 5 C for 17 weeks. The differences between both studies can be explained not only by the different content of GLS degradation products in sauerkrauts before storage, but also by the different chemical and microbial stability of these compounds in the distinct acidic environments present in sauerkrauts analysed in each work. ...
Article
The aim of this work was to investigate the influence of storage at 4 °C in conventional or nitrogen (N2)-enriched atmospheres for 3 months on the microbial status of sauerkraut obtained by natural fermentation or by Leuconostoc mesenteroides inoculation. The content of vitamin C, glucosinolate derivatives and the antioxidant activity of stored sauerkrauts were also evaluated. Aerobic/anaerobic mesophilic bacteria and lactic acid bacteria populations decreased sharply during N2 storage, whilst they increased during conventional storage. Ascorbigen and vitamin C levels decreased gradually during storage and no significant differences were found between both storage types. The concentration of nitriles and isothiocyanates decreased during storage and, in general, lower content of these compounds were found in N2-stored sauerkrauts. The antioxidant capacity of fermented cabbages was retained after storage at both conditions, and L. mesenteroides sauerkrauts presented significantly higher antioxidant activity at the end of the storage period when N2 atmosphere were used. Thus, the use of N2-atmosphere during refrigerated storage is a promising and cost-effective approach to improve the microbial quality of sauerkraut, and consequently, to extend its shelf-life. Sauerkrauts stored in these conditions had large antioxidant activity and retained high phytochemical concentrations.
... Depending on the type and conditions of processing, GLS undergo either enzymatic hydrolysis or thermal degradation resulting in the formation of biologically active compounds including indoles (e.g., indole-3-carbinol, I3C and 3,3 0 -diindolylmethane, DIM). The effect of fermentation on GLS degradation products has been poorly recognized [12,13]. The formation of some specific products like ascorbigen (ABG) is suggested [14]. ...
... During fermentation, as the pH decreases, this I3C reacts nonenzymatically with L-ascorbic acid to yield ABG, which is thought to be the dominant end product of indole GLS The mean values ± SEM from three independent experiments run in duplicate (protein) or triplicate (mRNA) are presented. The asterisk above the bar denotes significant difference of mean values from the control group (P \ 0.05) degradation in sauerkraut [12,14]. So far only a few and rather indirect studies on the anti-carcinogenic effects of ABG have been published, and its interaction with aryl hydrocarbon receptor (AhR) was suggested [24]. ...
... Traditional cabbage fermentation process contributes with various hydrolyzed compounds from GLs, such as ITCs, ascorbigen, cyanides, and nitriles [73][74][75]. It was suggested that the sauerkraut fermentation process hydrolyzed GLs predominantly to ITCs and allyl cyanide both in fermentation involving bacterial culture and in self-fermentation processes, while only small amounts of sulforaphane nitrile and goitrin were detected [73]. ...
... In addition, different lactic acid bacteria strains were evaluated as culture starters [74], and it was revealed that sauerkraut fermented by Lactobacillus sakei produced significantly more 3-methylsulphinylpropyl ITC, allyl ITC, and sulphoraphane than sauerkraut fermented by other strains. In contrast, it was found that predominantly ascorbigen was the product of GL hydrolysis in fermented cabbage, while ITCs and cyanides were detected only in traceable amounts [75]. The impact of Japanese style salt pickling process on the content of GLs in daikon, watercress, and nozawana was also studied [76]. ...
Article
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In recent decades, glucosinolates and isothiocyanates have attracted the interest of scientific community due to healthy properties of these bioactive compounds and their role as natural antimicrobials and anticarcinogenic agents. However, these compounds can lose their properties and transform into antinutrients depending on processing conditions. At this stage of investigation, there is a need in evaluation of the commonly accepted and new emerging methods in order to establish the optimum conditions for preserving healthy glucosinolates and isothiocyanates. This paper reviews the conventional and new promising technologies that can be useful for extraction of appropriate glucosinolates and isothiocyanates from natural sources (i.e., Brassica vegetables). The impact of different preservation processes on degradation of glucosinolates and isothiocyanates is also discussed.
... Sauerkraut is also reported to contain high levels of glucosinolate (GLS) breakdown products (Ciska and Pathak, 2004), such as isothiocyanates (ITC), indole-3-carbinol (I3C), indole-3-acetonitrile (I3ACN) and ascorbigen (ABG) (Ciska and Pathak, 2004;Martinez-Villaluenga et al., ...
... Sauerkraut is also reported to contain high levels of glucosinolate (GLS) breakdown products (Ciska and Pathak, 2004), such as isothiocyanates (ITC), indole-3-carbinol (I3C), indole-3-acetonitrile (I3ACN) and ascorbigen (ABG) (Ciska and Pathak, 2004;Martinez-Villaluenga et al., ...
... A well-defined compound, later denoted ascorbigen, was first isolated from the fresh juice of cabbage [10]. Later, ascorbigen was also found in other vegetables, such as Brussel sprouts, cauliflower, and broccoli, and seems to be a characteristic key compound in cruciferous greens [11][12][13][14][15]. In these plants, indole *Address correspondence to the authors at the University of Natural Resources and Life Sciences, Department of Chemistry, Muthgasse 18, A-1190 Vienna, Austria; E-mail: thomas.rosenau@boku.ac.at glucosinolates (glucobrassicin, 2) are found. ...
... Fig. (6). 13 C NMR spectrum of ascorbigen (1). The inset shows a zoom of the spectral region between 75 and 140 ppm, which contains the majority of the resonances. ...
Article
Ascorbigen (2-C-(3-indolyl)-methyl-α-L-xylo-hex-3-ulofuranosono-1,4-lactone, 1) is a breakdown product of glucobrassicins found in cruciferous vegetables, such as cabbage, cauliflower, Brussel sprouts, or broccoli, formed by direct C-alkylation of ascorbic acid (vitamin C) by (3-indolyl)-methyl intermediates under physiological conditions. It is a labile compound, and direct synthesis approaches are hampered by the oxidative instability of the indol moiety and ring transformations of the ascorbyl part. The latter have also impeded ascorbigen analytics for decades, and only recently different ascorbigens have been shown to represent mixtures of compounds rather than individual ascorbigen-type compounds. Following a review of pertinent literature, timely aspects of ascorbigen chemistry, including the most recent synthesis approaches and in-depth characterization of the compound, are presented.
... Dai prelievi effettuati nelle vasche di fermentazione durante il periodo estivo, il contenuto di glucosinolati totali nel liquido di governo risulta essere mediamente di 588,11±201,57 mg/kg e quindi maggiore rispetto ai valori riscontrati nel periodo invernale. La notevole variabilità, come riportano Ciska et al. (2004), può essere in parte dovuta alla perdita di composti volatili durante la fermentazione invernale, maggiormente prolungata nel tempo. È necessario considerare inoltre l'influenza della componente microbica che associata a modificazioni chimiche fisiche del prodotto (T°, pH, Aw, consistenza) determina consistenti "fluttuazione" dei valori analitici. ...
... Nel caso della sinigrina sono allylisotiocianati, allylcianati e 1-ciano-2-3-epitiopropano. In particolare gli isotiocianati prevalgono se il pH è compreso tra 4 e 5, mentre a valori di pH inferiori a 3,7 sono maggiormente concentrati i cianati. Ciska et al. (2004) riporta comunque che nei crauti la sinigrina è molto stabile e gli eventuali prodotti di degradazione non superano il 5%. Secondo i medesimi autori sarebbe invece consistente la presenza di ascorbigeni, composti che durante la fermentazione, al decrescere del pH, derivano dai glucosinolati ed in particolare dalla reazione dell'indolo con l'acido ascorbico, acido organico di cui questa crucifera è ricca (Martinez-Villaluenga et al., 2009). ...
Article
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Fermentation of the cruciferous white cabbage naturally occurs after the harvest of the vegetable. The aim of the present study was to evaluate, at microbiological and biochemical level, two industrial fermentations differing in temperature and season. Lactic acid populations were characterized by means of RAPD-PCR, revealing the presence of different bacterial species and strains. Biochemical analyses indicate that sauerkraut has a significant amount of glucosinolate, which is responsible for aroma development and the anti cancer properties of this vegetable. During the fermentative process, when the pH values gradually decrease, the hydrolysis products released by the glucosinolate react with the ascorbic acid to produce ascorbigen, compounds which are interesting for the health. Considering all the above aspects, sauerkraut could be considered as a "functional" canned food.
... Production of local vegetables, including red cabbage, plays an integral part in supplying healthy foods rich mainly in micronutrients and some phytochemicals such as vitamins C, K, β-carotene, minerals, fiber, total polyphenols, and glucosinolates [5]. Brassica vegetables are a rich source of bioactive compounds and epidemiological studies have confirmed that a high intake of these vegetables has been associated with the risk reduction of certain cancers, such as lung, colorectal, breast, and prostate [6]. ...
... Of the total indole glucosinolates, a higher content of glucobrassicin was determined in young shoots (70.1% of total indole GLS) in comparison to red headed cabbage (50% of total indole GLS). The total amount of and glucosinolates profile may vary significantly between tissues and organs: roots, leaves, seeds, and young sprouts and shoots [6,60]. The composition of glucosinolates in the variety of vegetables depends on many factors, as the type of cultivars, growing conditions, availability of nutrients, harvest date, and signal molecules associated with reaction to biotic and abiotic stresses. ...
Article
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Cruciferous vegetables are a valuable source of ingredients with health benefits. The most characteristic compounds of cruciferous vegetables with identified anticancer properties are glucosinolates. Young shoots and sprouts of red cabbage are becoming a popular fresh food rich in nutrients and bioactive compounds. The objective of this research was to determine, for the first time in a comprehensive approach, whether young shoots of red headed cabbage are a better source of selected nutrients and glucosinolates in the human diet in comparison to the vegetable at full maturity. The proximate composition (protein, fat, digestible carbohydrates, fiber), fatty acids profile, minerals (calcium, magnesium, potassium, sodium, iron, zinc, manganese, copper), as well as glucosinolates were examined. The red headed cabbage was characterized by a significantly larger amount of dry matter, and total and digestible carbohydrates in comparison to young shoots. The ready-to-eat young shoots, which are in the phase of intensive growth, are a better source of protein, selected minerals, and especially glucosinolates. The level of some nutrients can be enhanced and the intake of pro-healthy glucosinolates can be significantly increased by including young shoots of red cabbage into the diet.
... Among the fermented Brassica products, sauerkraut is a well-known traditional food made from shredded, brined white cabbage and it is commonly consumed in Europe. Ciska and Tolonen reported that fermentation results in complete degradation of glucosinolates and increased contents of health-promoting compounds, including sulforaphane, ABG and I3C (Ciska & Pathak, 2004;Tolonen et al., 2004). In addition, fermentation increased the antioxidant potential in Chinese Pak Choi (Harbaum, Hubbermann, Zhu, & Schwarz, 2008), red cabbage (Hunaefi, Akumo, & Smetanska, 2013) and white cabbage (Kusznierewicz, Ś miechowska, Bartoszek, & Namieśnik, 2008;Peñas et al., 2012). ...
... There are a few studies available about the effect of storage time and pasteurisation on glucosinolate content (Ciska & Honke, 2012;Ciska & Pathak, 2004;Peñas, Limón, Vidal-Valverde, & Frias, 2013). However, the influence of fermentation time on glucosinolates content has not yet been studied. ...
Article
A systematic investigation was carried out on the influence of fermentation on glucosinolates and their degradation products from fresh raw cabbage, throughout fermentation at 20 �C and storage at 4 �C. Glucosinolates were degraded dramatically between Day 2 and 5 of fermentation and by Day 7 there was no detectable amount of glucosinolates left. Fermentation led to formation of potential bioactive compounds ascorbigen (13.0 lmol/100 g FW) and indole-3-carbinol (4.52 lmol/100 g FW) with their higher concentrations from Day 5 to Day 9. However, during storage indole-3-carbinol slowly degraded to 0.68 lmol/100 g FW, while ascorbigen was relatively stable from Week 4 until Week 8 at 6.78 lmol/100 g FW. In contrast, the content of indole-3-acetonitrile decreased rapidly during fermentation from 3.6 to 0.14 lmol/100 g FW. The results imply a maximum of health beneficial compounds after fermentation (7–9 days) in contrast to raw cabbage or stored sauerkraut.
... The present study showed that both glucobrassicin and sinigrin were present in significant quantities; however, their concentrations were lower than values reported in the literature [24]. Ciska and Pathak [25] found that glucoiberin and sinigrin in the aliphatic group of GLS and glucobrassicin in the indole group of GLS to be dominating the GLS content in white cabbage, and constituting up to 90% of the total GLS present. The differences in GLS levels could be due to variations in genotype, variety, season, geographic location/climate, stage of maturity and growing conditions [26,27]. ...
Article
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Recent studies showed that Brassica vegetables are rich in numerous health-promoting compounds such as carotenoids, polyphenols, flavonoids, and glucosinolates (GLS), as well as isothiocyanates (ITCs) and are involved in health promotion upon consumption. ITCs are breakdown products of GLS, and typically used in the food industry as a food preservative and colouring agent. They are also used in the pharmaceutical industry due to their several pharmacological properties such as antibacterial, antifungal, antiprotozoal, anti-inflammatory, and chemoprotective effects, etc. Due to their widespread application in food and pharmaceuticals, the present study was designed to extract ITCs from York cabbage. In order to optimise the fermentation-assisted extraction process for maximum yield of ITCs from York cabbage, Box-Behnken design (BBD) combined with response surface methodology (RSM) was applied. Additionally, the GLS content of York cabbage was quantified and the effect of lactic acid bacteria (LAB) on GLS was evaluated. A range of GLS such as glucoraphanin, glucoiberin, glucobrassicin, sinigrin, gluconapin, neoglucobrassicin and 4-methoxyglucobrassicin were identified and quantified in fresh York cabbage. The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis, and also examined by appropriate statistical methods. LAB facilitated the degradation of GLS, and the consequent formation of breakdown products such as ITCs. Results showed that the solid-to-liquid (S/L) ratio, fermentation time and agitation rate had a significant effect on the yield of ITCs (2.2 times increment). The optimum fermentation conditions to achieve a higher ITCs extraction yield were: S/L ratio of 0.25 w/v, fermentation time of 36 h, and agitation rate of 200 rpm. The obtained yields of ITCs (45.62 ± 2.13 μM sulforaphane equivalent (SFE)/mL) were comparable to the optimised conditions, indicating the accuracy of the model for the fermentation-assisted extraction of ITCs. This method has good prospects in industrial applications for the extraction of ITCs, and can be helpful in the food, pharmaceutical and agricultural sectors.
... Benzyl cyanide was supplied by Sigma-Aldrich (Steinheim, Switzerland) and allyl cyanide was purchased from Fluka (Buchs, Switzerland). Ascorbigen was synthesised from indole-3-carbinol and ascorbic acid according to the method developed by Kiss and Neukom (1966) and described by Ciska and Pathak (2004). The chromatographic purity (HPLC) of the obtained compound reached 98.4%. ...
Article
A B S T R A C T This study identified glucosinolate (GLS) breakdown products and determined the relationships between such products and parent GLS in boiled Brussels sprouts. This is the first ever study to analyse all groups of GLS breakdown products (aliphatic, aralkyl and indole) in boiled vegetables. In the examined boiled Brussels sprouts, isothiocyanates were not determined in the edible parts or cooking water. The presence of seven breakdown products was determined as indole-3-acetonitrile, indole-3-carbinol, ascorbigen and 3,3'-diindolylmethane released form glucobrassicin, 3-butenylnitrile released from sinigrin, 4-methylsulfinylbutanenitrile released from glucoiberin, and 2-phenylacetonitrile released from gluconasturtiin. In the edible parts, the content of indole-3-acetonitrile and 3-butenylnitrile was particularly high at approximately 30 and 16 mol/100 g FW, which was equivalent to 54 and 9% of the initial value of the parent GLS, respectively.
... During shredding, glucobrassicin, the principal cabbage GLS, is transformed into I3C upon action of myrosinase. During fermentation, as the pH decreases, this indole reacts non-enzymatically with L-ascorbic acid to yield ascorbinogen (ABG), which is a dominant end product of indole GLS in sauerkraut (38,39). It was shown that ABG itself or in combination with the other indoles (I3C and sulforaphane) modulates the enzymes involved in xenobiotic metabolism inducing the CYP1A1 family. ...
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Our previous studies showed the diversified effect of cabbage juices and indoles on the estrogen metabolism key enzymes (CYP1A1, CYP1A2, CYP1B1) in breast epithelial cells differing in ER status, i.e., in tumorigenic-MCF7, MDA-MB-231 and non-tumorigenic-MCF10A cells. The aim of the present study was to further investigate the mechanism of chemopreventive action of cabbage juice and its active components by evaluating their effect on the expression of AhR, ERα, and Nrf2 using the same treatment regimen. The mRNA level of AhR and ERα was changed in a cell type-dependent manner and in general correlated with previously observed modulation of CYP expression. However, in most cases the alterations in mRNA were not accompanied by the changes in the level of relevant proteins. Marked differences were also found in the effect of cabbage juices and indoles; although both cabbage juices and indoles increased most of the NQO1 transcript levels in all tested lines, indoles also enhanced GSTP transcription in MCF7 and MDA-MB-231. Overall, the results of this study partly explain the mechanism behind the chemopreventive activity of white cabbage products and indicate that modulation of the expression of specific transcription factors may play an important role in this process.
... This GS composition is comparable to previous studies on white cabbage, although some studies report the sinigrin content of white cabbage to be higher compared to the glucoraphanin content (Ciska & Kozłowska, 2001;Ciska & Pathak, 2004;Fuller et al., 2007;Song & Thornalley, 2007;Wennberg, Ekvall, Olsson, & Nyman, 2006). The differences in the sinigrin/raphanin content described in literature could be due to the differences in the cultivar and cultivation conditions that are known to affect the GS profile and content substantially (Ciska, Martyniak-Przybyszewska, & Kozlowska, 2000;Kang, Ibrahim, Juvik, Kim, & Kang, 2006;Krumbein, Schonhof, & Schreiner, 2005). ...
Article
Steaming has been reported to better retain the glucosinolate (GS) content in Brassica vegetables than boiling. However, there is little information on the GS content, colour, and texture attributes in Brassica vegetables in relation to the duration of steaming. This study investigated the effect of the duration of steaming, which was applied in certain commercial preparation processes, on the GS content, colour, and texture of white cabbage. Results showed that the total accessible content of GSs increases initially during steaming until 10 min followed by a consistent decline up to 180 min. This observed initial increase is mainly due to the content of aliphatic GSs rather than indole GSs, which tend to decrease from the start of steaming. A mathematic model for the observed behaviour of the GSs, taking into account several mechanisms, is proposed and fitted to the data. The intensity of the green colour of the cabbage slightly increased during the first 15 min of steaming followed by a decrease onwards. The hardness showed a continuous decline during the entire steaming duration. The study indicates that steaming up to 10 min could promote the health properties as well as the colour and texture attributes of steamed cabbage.
... Isothiocyanates (ITCs) consist of aliphatic and aromatic compounds generated from the hydrolysis of glucosinolates (GLCs) by myrosinase in cruciferous vegetables such as cauliflower, broccoli, cabbage, horseradish and mustard (Ciska and Pathak 2004;Delaquis and Mazza 1995;Whitmore and Naidu 2000). Myrosinase and GLCs are physically separated within plant cells. ...
Article
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Reduction of the AFs produced by Aspergillus parasiticus CECT 2681 in wheat tortillas by isothiocyanates (ITCs) from oriental and yellow mustard flours was evaluated in this study. Polyethylene plastic bags were introduced with wheat tortillas contaminated with A. parasiticus and treated with 0, 0.1, 0.5 or 0.1 g of either oriental or yellow mustard flour added with 2 ml of water. The wheat tortillas were stored at room temperature during 1 month. The quantification of the AFs produced was analyzed by liquid chromatography (LC) coupled to the mass spectrometry detection in tandem (MS/MS). Gaseous allyl isothiocyanate (AITC) from oriental mustard was more effective than p-hydroxybenzyl isothiocyanate (p-HBITC) from yellow mustard to inhibit the production of AFs. More importantly, 1 g of AITC was able to reduce >90 % of AFs B1, B2, G1 and G2. p-HBITC is less stable and volatile than AITC, leading to a much lower AFs (average of 17.7 to 45.2 %). Further studies should investigate the use of active packaging using oriental mustard flour and water to reduce the production of AFs by Aspergillus species in bakery goods.
... Benzyl cyanide was obtained from Sigma-Aldrich (Switzerland) and allyl cyanide was purchased from Fluka (Poland). Ascorbigen was synthesized from indole-3-carbinol and ascorbic acid according to Kiss and Neukom (1966) as described earlier (Ciska & Pathak, 2004). Chromatographic purity (HPLC) of the compound obtained reached 98.4%. ...
... Isothiocyanates (ITCs) consist of aliphatic and aromatic compounds generated from the hydrolysis of glucosinolates (GLCs) by myrosinase in cruciferous vegetables such as cauliflower, broccoli, cabbage, horseradish and mustard (Ciska and Pathak 2004;Delaquis and Mazza 1995;Whitmore and Naidu 2000). Myrosinase and GLCs are physically separated within plant cells. ...
... It can be eaten raw or after cooking. During the fermentation process, cabbage GLSs are degraded, with formation of ITCs and other degradation products (such as indole-3-acetonitrile as well as indole-3-carbinol that reacts with ascorbic acid forming ascorbigen) [123,191], so that no detectable amounts of GLSs are present in sauerkraut at the end of the fermentation process [126]. The type and the level of GLS degradation products are strongly dependent on the content of native GLSs of the raw materials, as well as on the fermentation conditions. ...
Chapter
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Glucosinolates are secondary plant metabolites that have attracted researcher’s attention due to their potential chemopreventive activity. More than 120 different glucosinolates have been identified in plants, and several of these compounds have been studied for the potential anti-cancerogenic effect of their metabolic breakdown products (mainly ITCs). Glucosinolates are peculiar of vegetables belonging to Brassicaceae family but are present also in few other species (capers, papaya, and moringa) used for human consumption. The type and concentration of glucosinolates in food are highly variable depending on several factors, such as genetics, cultivation site, cultivar, growth conditions, developmental stage, plant tissue, post-harvest handling, and food preparation methods. As types and concentration are also the main determinant of their biological activities, estimates of their content in food are essential tool to understand if a certain diet is adequate to deliver qualitatively and quantitatively appropriate glucosinolates and ITCs. The aim of this chapter is to describe qualitative and quantitative glucosinolate distribution among commonly eaten food, as well as the effect of the post-harvest handling on the glucosinolate food content.
... In the third trimester, secretion of indole increased by 2.03 times, indicating a significant increase in the degradation of tryptophan in late pregnancy. 3-indoleacetonitrile is a form of dietary indole common in cruciferous vegetables, such as cabbage, cauliflower, broccoli, and Brussels sprouts, and it has shown the ability to prevent tumors in various animal models and human populations (Ciska and Pathak 2004;Smith et al. 2005;Michnovicz and Bradlow 1990). 3-indoleacetonitrile was increased significantly in the second trimester (FC = 2.12, compared with the first trimester) and in the third trimester (FC = 1.67, compared with the second trimester), which might further have confirmed the enhancement of tryptophan metabolism in pregnant women throughout pregnancy. ...
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Introduction The maternal body often faces unique physiological challenges in amino acid metabolism due to the continuous requirement of nutrients and substrates for fetal development and additional energy stores for labor and lactation during pregnancy. Objective The aims of the present study is to find out the metabolites involved in amino acid metabolism in a large longitudinal healthy pregnant cohort and provide baseline data for future studies of pregnancy and disease from in utero environmental stress factors. Method We conducted a UPLC-QTOFMS based-urine metabolomics study to investigate the dynamic amino acid metabolic profiles and pathways of 232 healthy pregnant women in their first, second and third trimesters. After multivariate classification to select the metabolites with the strongest contributions to dynamic alterations in normal pregnancy, we applied the method of standard deviation step (SDSD) down for statistical significance analysis to enhance the value of metabolites in clinical practice. Results Kynurenic acid, an endogenous antagonist of N-methyl-d-aspartate receptors, increased significantly in middle pregnancy. l-aspartyl-4-phosphate, a potential marker for lower tolerance against fatigue of human body, decreased significantly in the third trimester. Cysteinylglycine, a pyrolysis product of glutathione, significantly increased in late pregnancy. These findings presented a novel insight into normal pregnancy-related regulation of the generation of excitatory neurotransmitter receptor antagonists, maternal fatigue, oxidative stress and so on. Conclusion This normal pregnancy related amino acid metabolic profile as well as the pathways information might be valuable to explore the complex mechanisms of physiological metabolic challenge in amino acid metabolism with the potential capacity to generate a novel hypothesis, which in turn could provide an ideal start for a large-scale epidemiological study of women who subsequently develop diseases, e.g., gestational depression.
... Thus, it cannot be excluded that these activities were combined from the beginning of the fermentation. The study of Mullaney et al. [77] showed that some LAB shifted the degradation of GLS into nitrile formation; however, the majority of studies reported that isothiocyanates are the main product of the GLS degradation during fermentation [78,79]. A recent study evaluating the changes of GLS showed that the direction of hydrolysis depends on the stage of fermentation [72]. ...
Article
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Fermentation is a method of food preservation that has been used for centuries. Lactic acid fermentation, apart from extending the shelf-life of vegetables, affects significantly the flavour of food products. In this review, the formation of flavour, including both taste and aroma, in fermented Brassica vegetables is summarized. The flavour-active compounds are generated in various metabolic pathways from many precursors present in raw materials used for fermentation. In Brassica vegetables, a unique group of chemicals, namely glucosinolates, is present, which significantly influence the flavour of fermented products. In this summary, we took a closer look at the flavour of two of the most commonly eaten worldwide fermented Brassica products, which are sauerkraut and kimchi. Finally, the needs and directions for future studies were addressed.
... Almost any vegetable can be fermented, and fermenting farm-fresh produce is a great way to provide good nutrition. Fermentation of vegetable alone or a mixture of different kinds, along with herbs and spices, provide a great variety of nutrient foods (Ciska and Pathak, 2004). ...
Article
Fermentation is one of the safest and most economical means of producing foods acceptable to human beings. It improves the nutritional quality of foods by increasing the bioavailability and thus, renders the food safe palatable and easily acceptable to mankind. The present study showed the effects of fermentation on the nutritional quality and safety of fermented foods with respect to nutrient composition and digestibility measures. Sauerkraut and fermented mixed vegetable were selected for study and the effects of fermentation on nutrient were observed. Digestibility, shelf-life and biochemical aspects were also studied. Level of all principle nutrients was significantly increased. In course of fermentation, total sugar and reducing sugar in the brine increased slowly to 3% and 2%, respectively up to 8th day and then decreased in sauerkraut fermentation. The maximum total acidity (1.98-2.22%) was observed on 15th day in fermented mixed vegetables. The pH of the shredded cabbage was 6.9 and decreased to around 4 after 15 days and then remained constant.
... Fermentation is an old processing method, and fermented Brassica vegetables, such as sauerkraut and kimchi, are important in traditional diets. Conventional fermentation has been reported to substantially reduce GSLs (Ciska & Pathak 2004, Martinez-Villaluenga et al. 2009, Tolonen et al. 2004. Degradation may occur during fermentation by (a) enzymatic degradation by myrosinase resulting from softening or disruption of the cell wall and (b) microbial degradation when microorganisms possess myrosinase-like enzymes (Hanschen et al. 2014). ...
Article
Glucosinolates (GSLs) are a class of sulfur-containing compounds found predominantly in the genus Brassica of the Brassicaceae family. Certain edible plants in Brassica, known as Brassica vegetables, are among the most commonly consumed vegetables in the world. Over the last three decades, mounting evidence has suggested an inverse association between consumption of Brassica vegetables and the risk of various types of cancer. The biological activities of Brassica vegetables have been largely attributed to the hydrolytic products of GSLs. GSLs can be hydrolyzed by enzymes; thermal or chemical degradation also breaks down GSLs. There is considerable variation of GSLs in Brassica spp., which are caused by genetic and environmental factors. Most Brassica vegetables are consumed after cooking; common cooking methods have a complex influence on the levels of GSLs. The variation of GSLs in Brassica vegetables and the influence of cooking and processing methods ultimately affect their intake and health-promoting properties. Expected final online publication date for the Annual Review of Food Science and Technology, Volume 12 is March 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
... [48] Found notable degradation products of glucosinolate in cucumbers fermented with Lactobacillus sakei compared to cucumbers manufactured with lactic acid bacteria starter cultures. [49] Reported that ascorbigen, a compound resulted from a degradation product reaction of indole glucosinolate (glucobrassicin) and ascorbic acid, is the cucumbers' dominant glucosinolate degradation product. Glucoraphinin existed in fresh cucumbers was converted over the fermentation into sulforphorane, however, sulforphorane was a relatively small glucosinolate degradation product in fermented cucumbers. ...
Chapter
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Cucumber sometimes used in sodium chloride solution as a substrate in lactic acid bacteria fermentation. The good fermentation always depending on many overlapped physical, chemical and microbial factors related with suspension of a strong and porous vegetables in a fluid. Keeping the cucumber integrity is very critical issue, and this may affect on the fermentation of liquid ingredients. This chapter tries to focus on the current efforts that conducting to control on the factors that affecting on cucumber fermentation. Modern and advanced technologies of recent studies are included within this chapter just like reducing the brining sodium chloride concentration, fresh cucumber gas exchange to develop their brining properties by using lactic acid bacteria cultures, developing an anaerobic cucumber fermentation tank system; preventing of cucumber gaseous spoilage by pouring of CO 2 from fermentation brines.
... In particular, glucobrassicin is hydrolyzed into indol-3-carbinol (I3C) by myrosinase and, as the pH decreases during cabbage fermentation, this indole compound reacts nonenzymatically with ascorbic acid to yield ascorbigen (ABG) (Wagner and Rimbach, 2009). Studies have shown that ABG is the main GLS breakdown compound in sauerkraut, and it is present at levels between 3 and 18 μmol/100 g fw (Ciska and Pathak, 2004;Martinez-Villaluenga et al., 2009;Peñas et al., 2010bPeñas et al., , 2012aPeñas et al., , 2015Palani et al., 2016). The anticarcinogenic properties of ABG due to its ability to induce activation of xenobiotic-metabolizing enzymes and apoptosis of tumoral cells have been well established (Stephensen et al., 1999;Bonnesen et al., 2001;Kravchenko et al., 2001). ...
Chapter
Sauerkraut is a traditional vegetable product usually produced by spontaneous fermentation that relies on lactic acid bacteria (LAB) naturally present in white cabbage. However, current trends on sauerkraut production propose the application of starter cultures in order to ensure a uniform quality of the product. Besides its high nutritional value, there are numerous in vitro investigations and some epidemiological data suggesting the potential positive effects of sauerkraut on health. These health-promoting properties are supported by strong evidence obtained from experimental studies, demonstrating that specific phytochemicals of sauerkraut have antioxidant, antiinflammatory, and a chemopreventive action against certain types of cancer. This chapter provides an overview of the production process of sauerkraut and its nutritional and phytochemical composition. The scientific data supporting the health benefits of sauerkraut will be also reviewed.
... According to Ciska & Pathak (2004), GLS are completely degraded during the fermentation of white cabbage. Comminution of cruciferous vegetables leads to the release of myrosinase (thioglucoside glucohydrolase, EC 3.2.3.1) from the cellular structures. ...
Article
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The aim of this paper was to evaluate the influence of different indigenous lactic acid bacteria isolates – as a single culture or bacterial consortium - on the functional and physicochemical properties of fermented curly kale juice. All tested variants exhibited good growth parameters, manifested by efficient pH lowering, increases in acidity, and fructose and glucose metabolism, as well as a significant inhibition of pathogens. A slight increase in total phenolic content was observed, while antioxidant activity remained unchanged. L. sakei and MIX A were associated with an increase in riboflavin and pyridoxine content, while L. plantarum only contributed to an increase in vitamin B6 content. Bioconversion of individual phenolic compounds, carotenoids, and glucosinolates strongly depended on the strain-specific metabolism. In the process, the levels of ferulic acid and other hydroxycinnamic acids were maintained, while the content of 9-cis lutein increased. Considering presented results and our previous research regarding probiotic features of LAB strains, among tested starter cultures - L. plantarum seemed to possess the best characteristics as a potential starter culture for controlled fermentation of curly kale juice.
... Ciska and Pathak reported that ascorbigen increased significantly reaching 14 µM/100 g f.w. in pasteurized fermented product (E. Ciska and Pathak 2004). Nevertheless, Sarvan et al. identified that blanching before fermentation inactivated myrosinase and preserved GLSs (Sarvan et al. 2013). ...
Article
Red and white cabbages (Brassica oleracea var. capitata f. rubra and alba, respectively) are two of the most commercially valued vegetables in crucifers, well-recognized for their unique sensory and nutritive attributes in addition to a myriad of health-promoting benefits. The current review addressed the differential qualitative/quantitative phytochemical make-ups for the first time for better utilization as nutraceuticals and to identify potential uses based on the chemical makeup of both cultivars (cvs.). in addition, extraction methods are compared highlighting their advantages and/or limitations with regards to improving yield and stability of cabbage bioactives, especially glucosinolates. Besides, the review recapitulated detailed action mechanism and safety of cabbage bioactives, as well as processing technologies to further improve their effects are posed as future perspectives. white and red cabbage cvs. revealed different GLSs profile which affected by food processing, including enzymatic hydrolysis, thermal breakdown, and leaching. in addition, the red cultivar provides high quality pigment for industrial applications. Moreover, non-conventional modern extraction techniques showed promising techniques for the recovery of their bioactive constituents compared to solvent extraction. All these findings pose white and red cabbages as potential candidates for inclusion in nutraceuticals and/or to be commercialized as functional foods prepared in different culinary forms.
... During this process, GLS content is affected, to the extent that no GLS are detected in fermented cabbage and stored sauerkraut (Martinez-Villaluenga et al., 2009). However, different works reported the formation of several GLS breakdown products, including indole-3-carbinol, indole-3-acetonitrile, thiocyanate ion, and ascorbigen from glucobrassicin, 2-phenylethyl ITC from gluconasturtiin, and 1-cyano-3-methyl sulfinylpropane from glucoiberin, among many others (Ciska and Pathak, 2004;Daxenbichler et al., 1980;Tolonen et al., 2002). ...
... Fermentation is a promising route to alter the chemical profiles of vegetables and potentially enhance their biological activities (Di Cagno, Coda, De Angelis, & Gobbetti, 2013). The influence of processing and fermentation on the bioactivities of cruciferous vegetables such as cabbage, mustard leaf and broccoli has been studied in terms of total polyphenol content, antioxidant capacity, glucosinolates and breakdown products (Ciska & Pathak, 2004;Maryati, Susilowati, Melanie, & Lotulung, 2017;Nugrahedi, Widianarko, Dekker, Verkerk, & Oliviero, 2015;Palani et al., 2016). Different LAB species have different fermentation characteristics which have been shown to produce a diverse range of different metabolites in fermented vegetable juices (Tomita, Saito, Nakamura, Sekiyama, & Kikuchi, 2017). ...
Article
This study investigated the effect of lactic acid bacteria (LAB) fermentation on the chemical profile of autoclaved broccoli puree, using 7 broccoli-derived LAB isolates (named F1-F5, BF1 and BF2). The total concentrations of glucosinolates (glucoiberin, progoitrin and glucoraphanin) and 10 major phenolics significantly increased from trace level and 289 μg total phenolics/g dry weight (DW) respectively in autoclaved broccoli to 55 to ∼359 μg/g DW and 903 to ∼3105 μg/g DW respectively in LAB fermented broccoli puree. Differential impacts of LAB isolates on the chemical composition of autoclaved broccoli were observed, with the major differences being the significant increase in phloretic acid after fermentation by F1-F5 and an elevated glucoraphanin level in ferments by F1 and BF2. LAB fermentation is a promising way to increase the content of glucosinolates and polyphenolic compounds in broccoli, making the ferments attractive for use as functional ingredients or as a whole functional food.
... Using high-vacuum distillation and subsequent solvent extraction using pentane-DCM, the authors identified 6 VSCs, including three alkyl thiophenes, ethyl 3mercaptopropionate, BITC, and 2-phenylethyl isothiocyanate [131]. The latter compound is the second isothiocyanate identified in papaya, most likely derived from the glucosinolate named gluconasturiin [132]. In the same year, Idstein & Schreier used the same analytical procedure to identify five VSCs, including methyl thiocyanate and ethyl thiocyanate [133]. ...
Article
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Global production and demand for tropical fruits continues to grow each year as consumers are enticed by the exotic flavors and potential health benefits that these fruits possess. Volatile sulfur compounds (VSCs) are often responsible for the juicy, fresh aroma of tropical fruits. This poses a challenge for analytical chemists to identify these compounds as most often VSCs are found at low concentrations in most tropical fruits. The aim of this review is to discuss the extraction methods, enrichment techniques, and instrumentation utilized to identify and quantify VSCs in natural products. This will be followed by a discussion of the VSCs reported in tropical and subtropical fruits, with particular attention to the odor and taste attributes of each compound. Finally, the biogenesis and enzymatic formation of specific VSCs in tropical fruits will be highlighted along with the contribution each possesses to the aroma of their respective fruit.
... The quantification of I3C is usually performed by LC employing either UV (Ciska & Pathak, 2004) or fluorescence detection (Aleksandrova, Korolev, & Preobrazhenskaya, 1992;Lee et al., 2010). In addition, methods using GC have been reported (Latxague, Gardrat, Coustille, Viaud, & Rollin, 1991;Tolonen et al., 2002). ...
Article
Broccoli is a rich source of bioactive compounds. Among them, sulforaphane and indole-3-carbinol have attracted a lot of attention, since their consumption is associated with reduced risk of cancer. In this work, the development of an efficient and direct method for the simultaneous determination of sulforaphane and indole-3-carbinol in broccoli using UPLC-HRMS/MS is described. The correlation coefficient, and limits of detection (LOD) and quantification (LOQ) were 0.993, 0.77 mg/L and 2.35 mg/L for sulforaphane and 0.997, 0.42 mg/L, 1.29 mg/L for indole-3-carbinol, respectively. The content of sulforaphane and indole-3-carbinol varied between 72±9 to 304±2 mg and 77±1 to 117±3 mg per 100 g of fresh florets, respectively. Taking into consideration the differences in cultivar, geography, season and environmental factors, the results agreed with values published in the literature using other techniques.
... It can be eaten raw or after cooking. During the fermentation process, cabbage GLSs are degraded, with formation of ITCs and other degradation products (such as indole-3-acetonitrile as well as indole-3-carbinol that reacts with ascorbic acid forming ascorbigen) [123,191], so that no detectable amounts of GLSs are present in sauerkraut at the end of the fermentation process [126]. The type and the level of GLS degradation products are strongly dependent on the content of native GLSs of the raw materials, as well as on the fermentation conditions. ...
Chapter
Glucosinolates are secondary plant metabolites that have attracted researcher’s attention due to their potential chemopreventive activity. More than 120 different glucosinolates have been identified in plants, and several of these compounds have been studied for the potential anti-cancerogenic effect of their metabolic breakdown products (mainly ITCs). Glucosinolates are peculiar of vegetables belonging to Brassicaceae family but are present also in few other species (capers, papaya, and moringa) used for human consumption. The type and concentration of glucosinolates in food are highly variable depending on several factors, such as genetics, cultivation site, cultivar, growth conditions, developmental stage, plant tissue, post-harvest handling, and food preparation methods. As types and concentration are also the main determinant of their biological activities, estimates of their content in food are essential tool to understand if a certain diet is adequate to deliver qualitatively and quantitatively appropriate glucosinolates and ITCs. The aim of this chapter is to describe qualitative and quantitative glucosinolate distribution among commonly eaten food, as well as the effect of the post-harvest handling on the glucosinolate food content.
... Glucosinolates were identifi ed by comparing their retention times with those of known reference compounds or on the basis of available literature data. The presence of aliphatic GLS not having a standard was also additionally confi rmed with the GC-MS analysis of respective degradation products using a gas chromatograph Agilent 7890A equipped with a mass detector 5975C VL, as described earlier [Ciska & Pathak, 2004]. Glucotropaeolin (Merck, Darmstadt, Germany) was used as the internal standard for quantifi cation. ...
Article
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In comparison with other cruciferous vegetables, horseradish has rarely been the object of scientific research, and the knowledge about the composition, content and distribution of glucosinolates (GLS) in different organs of horseradish plants is limited. Therefore, the aim of this study was to evaluate changes in the GLS content in leaves and roots of four horseradish landraces during the growing season. The presence of 13 GLS was determined in the examined horseradish tissues, and glucoraphanin, glucoraphenin and napoleiferin were noted for the first time in the species. During the growing season, the content of individual GLS changed significantly. The rate and direction of these changes varied across the examined landraces and plant organs. In the leaves, between May and June, the content of sinigrin, the main GLS in all horseradish landraces, decreased in Bavarian (40%) and Hungarian (11%) horseradish, increased (22%) in Creamy horseradish, whereas in Danish horseradish, the difference was not significant. Despite the changes observed in the first two months, the highest content of sinigrin was noted in July in all horseradish landraces. During the growing season (August-October), the content of sinigrin fluctuated in the roots of Creamy and Danish landraces, reaching the highest level in October and September, respectively, whereas in the roots of Hungarian and Bavarian landraces, sinigrin concentrations continued to increase and peaked in October. Changes in the content of other, minor GLS during the growing season often differed from those noted in sinigrin levels.
Article
This research aimed to study the fermentation of white cabbage (Brassica oleracea) replacing salt, totally or partially, with halophyte Salicornia ramosissima, to reduce the sodium content in the final products. Three fermentation trials of cabbage were done: A with 2.91% salt (~ 1.15% Na) (control); B with salicornia (~ 1.56% salt equivalent, ~ 0.34% Na); and C with salt and salicornia (~ 1.94% salt equivalent, ~ 0.49% Na). The fermentation profile was followed by the physicochemical (pH, total acidity) and microbial parameters [mesophilic microorganisms (MM), lactic-acid bacteria (LAB), coliforms and fungi]. The content of phenolics and antioxidant activity in the fermented products were also measured. In all experiments, there was an increase, followed by a stabilization of the MM (5.5–7.2 Log CFU/g) and LAB populations (5.4–6.6 Log CFU/g) and a decrease of fungi and coliforms until they disappeared. A decrease in pH (< 4) and a rise in acidity (~ 1.0%) were observed throughout the fermentations. The phenolics and antioxidant activity increased during fermentation, being significantly higher in C (37.3 mg/100 g and 3.63 mmol Trolox/100 g, respectively). The fermentation of cabbage with salicornia results in the final products having similar microbial quality to the control, but with a reduction of sodium and an increase in the antioxidant activity.
Article
The chemistry of glucosinolates and their behavior during food processing is very complex. Their instability leads to the formation of a bunch of breakdown and reaction products that are very often reactive themselves. Although excessive consumption of cabbage varieties has been thought for long time to have adverse, especially goitrogenic effects, nowadays, epidemiologic studies provide data that there might be beneficial health effects as well. Especially Brassica vegetables, such as broccoli, radish, or cabbage, are rich in these interesting plant metabolites. However, information on the bioactivity of glucosinolates is only valuable when one knows which compounds are formed during processing and subsequent consumption. This review provides a comprehensive, in-depth overview on the chemical reactivity of different glucosinolates and breakdown products thereof during food preparation.
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Erratum to: Food Eng Rev (2014) DOI 10.1007/s12393-014-9104-9The authors would like to mention some references of the above-published article that are missing:Van Eylen D, Oey I, Hendrickx M, Van Loey A (2007) Kinetics of the stability of broccoli (Brassica oleracea cv. italica) myrosinase and isothiocyanates in broccoli juice during pressure/temperature treatments. J Agric Food Chem 55:2163-2170Clariana M, Valverde J, Wijngaard H, Mullen AM, Marcos B (2011) High pressure processing of swede (Brassica napus): impact on quality properties. Innov Food Sci Emerg Technol 12:85-92Dai R, Lim L-T (2014) Release of allyl isothiocyanate from mustard seed meal powder. J Food Sci 79:E47-E53Moreover, some references were incorrectly listed, and the numbering should be changed as follows:Page 2, right column, “Indole GLs are derived from tryptophan and their content in some plants is rather high, such as Brussel sprout and broccoli [138]”.The reference number should be [13]. ...
Article
Racemic sulforaphane, which was derivatized with (S)-leucine (L-leucine), was resolved by a reversed phase HPLC with UV detection. The optimum mobile phase conditions were found to be 10 mM citric acid (pH 2.8) containing 22% methanol at 35 °C using detection at 254 nm. Sulforaphane enantiomers in florets and stems of five brands of broccoli and leaves and stems of three brands of broccoli sprouts were analyzed by the proposed HPLC method. Both sulforaphane enantiomers were detected in all the samples. The S/R ratios of sulforaphane in broccoli samples were 1.5-2.6/97.4-98.5% for florets and 5.0-12.1/87.9-95.0% for stems. The S/R ratios in broccoli sprout samples were higher than those in broccoli samples and were found to be 8.3-19.7/80.3-91.7% for leaves and 37.0-41.8/58.2-63.0% for stems. (S)-Sulforaphane detected in the broccoli and its sprout samples was doubtlessly identified by separately using an HPLC with a chiral column (Chiralpak AD-RH) and mass spectrometry.
Chapter
Bioactive compounds have been an important subject in food science and technology because of their potential benefits to health and wellness. Given that modern lifestyles have a profound influence on public health and that these bioactive substances are widely distributed in foods of all sources, food processing is an adequate means to increase their bioavailability and prevent losses thus contributing to the control of chronic diseases. In some cases, processing can be instrumentalto make a substance bioactive, as are the cases of isoflavones, isothiocyanates and thiosulfinates, for which thermal and mechanical treatments are necessary to make them available. In this chapter the known chemical changes responsible for the generation and alterations of glucosinolates, thiosulfinates, flavonoids, stilbenes and coumarins are presented and discussed with a focus on the role of processing techniques and their impact on the health properties.
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Cabbage is one type of vegetable that is often consumed. Cabbage contains gallic acid and sulforaphane compounds which potentially used as an antioxidant. Gallic acid and sulforaphane are produced from the hydrolysis reaction, which occurs by fermentation. Therefore, this research was focused on the effect of NaCl addition and the incubation time on the gallic acid concentration during cabbage fermentation using L. plantarum. The addition of NaCl used were 0 %, 0.5 %, 1.0 %, 1.5 %, and 2.0 % (w/v). While the incubation time used were 2, 3, 4, 5, and 6 days. The fermentation conditions used were 5 % (v/v) inoculum volume and pH 6. Gallic acid in fermented cabbage (biomass and filtrate) were determined using Folin-Denis method. The antioxidant analysis was determined using DPPH method. The optimum conditions were obtained at the addition of 1.0 % NaCl for 4 days fermentation. During these conditions, the gallic acid produced in biomass and filtrate were equal to 4.726 mg/100 g FW and 147.857 mg/100 g FW, respectively. Sulforaphane and gallic acid have potential as antioxidants with IC 50 valuesof 95.113 mg/L and 21.648 mg/L, respectively.
Article
In this work, a naturally occurring phenyl isothiocyanate (PITC) molecule was covalently bonded to the surface of microfibrillated cellulose (MFC) to prepare contact active antimicrobial surfaces based on presently used materials. A preliminary comparative study was carried out on the reactivity of the hydroxyl group of cellulose and lignin compounds with phenyl isothiocyanate. Classical second order reaction kinetics was established between the hydroxyl containing model alcohol compounds and phenyl isothiocyanate with the conversion up to 80% in 20. min. X-ray diffraction and scanning electron microscopy (SEM) were utilized to monitor the change in crystallinity and morphology of the surface after grafting. Further, the successful immobilization of isothiocyanate was confirmed after grafting with contact angle measurements, Fourier transform infrared spectroscopy (FTIR) and presence of sulfur by elemental analysis. Antibacterial activity was investigated against gram positive bacteria, Staphylococcus aureus and Bacillus subtilis, in dynamic and static experimental conditions. The PITC grafted MFC did not exhibit a bactericidal activity in dynamic condition, however, a very strong activity (complete killing) was revealed under static condition with 3.5 log initial CFU. These findings may help in the establishment of new and safe strategy for the preparation of antimicrobial contact surfaces for packaging applications.
Article
Oil palm empty fruit bunch (EFB) fibers were subjected to solvolytic liquefaction to convert into liquid products using ethylene glycol (EG) as a supporting agent. The process was carried out at 250°C for 60 min. The water-insoluble product fraction was exhaustively extracted with acetone (ASL fraction) to separate all less polar. FTIR and comparative analytical pyrolysis GC/MS of the parent EFB fiber and the ASL fraction confirmed the formation of larger amounts of long-chain lipophilic compounds under liquefaction conditions. Furthermore, a considerable amount of less polar thermal lignin degradation products were obtained comprising all of the three main lignin building blocks, i.e. 4-hydroxyphenyl-(P units), 4-hydroxy-3-methoxyphenyl-(G units) and 3,5-dimethoxy-4-hydroxyphenyl (S units) substituted compounds. 4-Prop-2-en-1-yl substituted phenolic compounds contributed mostly to the cumulated peak area of all lignin derived pyrolysis products obtained by analytical Curie point pyrolysis GC/MS at 600C. The results of both instrumental-analytical methods confirm the formation of phenol and its derivatives, furan derivatives, organic acids, hydrocarbon, ester, benzene groups and alcohols.
Article
The influence of postharvest UV-B on its own and in combination with fermentation (e.g. sauerkraut production) on formation and degradation of bioactive compounds was investigated in white cabbage, processed according to traditional Chinese fermentation methods. The pattern of polyphenols was affected by postharvest UV-B: Newly formed coumaroylglycoside, feruloylglycoside, caffeoylglycoside (up to 1 mg/g dry matter; 4 days) and quercetintriglycoside (0.4-0.5 mg/g dm; 4 days) might be related to postharvest increase in enzyme activity in the biosynthesis. Decreasing contents were observed for the glucosinolates glucobrassicin and 4-methoxyglucobrassicin, but the formation of the degradation products dihydroascorbigen and dihydro-4-methoxyascorbigen, which might be related to cell shrinking as mechanical damage. Fermentation resulted in deglycosidation of hydroxycinnamic acids. Newly generated cinnamic acid from coumaric acid aglycone was detected in fermented plant material combined with UV-B (50 μg/g). Glucosinolates and dihydroascorbigens were completely degraded. This study shows exemplary UV-B as a supplemental step to improve the nutritional quality of processed plants.
Chapter
The healthiness of a vegetable cannot solely be inferred from the amount of health-promoting compounds in the raw materials. Brassica vegetables, for example, are consumed mostly after processing to improve palatability and to extend the shelf life. However, processing also results to various changes in the content of glucosinolates which intakes are associated with a reduced risk of several cancers. The large variety in cooking practices and processing methods affect the glucosinolate content in the vegetables, particularly due to processes that allow for enzymatic hydrolysis and thermal degradation of glucosinolates, and leaching of the bioactive components. Knowledge on the effect of preparation and processing of Brassica vegetables is important to evaluate the healthiness of the consumed product and to investigate mechanisms to retain high glucosinolate levels at the stage of consumption and to increase the intake of health-protective compounds by the consumer. By using a mechanistic approach, the fate of glucosinolates during different processing and preparation methods and conditions can be explained. Boiling and blanching reduce the glucosinolate content significantly particularly because of the mechanisms of leaching following cell lysis and diffusion, and partly due to thermal and enzymatic degradation. Steaming, microwave processing, and stir frying either retain or only slightly reduce the glucosinolate content due to low degrees of leaching. These methods can enhance the accessibility of glucosinolates from the plant tissue. Fermentation reduces the glucosinolate content considerably, the underlying mechanisms are not yet completely clear, but enzymatic breakdown seems to play an important role. Studying the changes of glucosinolates during processing by a mechanistic approach is shown to be valuable to redesign the processing and to reformulate the product for improving health benefits of these compounds.
Article
Die Chemie von Glucosinolaten und ihre Reaktionen während der Lebensmittelverarbeitung sind sehr komplex. Aufgrund ihrer Instabilität entsteht eine ganze Reihe von Abbau- und Reaktionsprodukten, die häufig ebenfalls reaktiv sind. Obwohl der übermäßige Genuss von Kohlsorten lange Zeit mit nachteiligen, vor allem goitrogenen (kropfbildenden) Wirkungen in Verbindung gebracht wurde, weisen aktuelle Ergebnisse aus epidemiologischen Studien auch auf potenziell positive Gesundheitseffekte hin. Insbesondere Gemüse aus der Familie der Kreuzblütler (Brassicaceae) wie Broccoli, Rettich oder Kohl sind reich an diesen interessanten pflanzlichen Metaboliten. Informationen zur Bioaktivität von Glucosinolaten sind aber nur dann von Nutzen, wenn man weiß, welche Verbindungen bei der Verarbeitung gebildet und anschließend verzehrt werden. Dieser Aufsatz bietet eine umfassende und detaillierte Übersicht über die chemische Reaktivität verschiedener Glucosinolate und ihrer Abbauprodukte während der Lebensmittelzubereitung.
Article
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Glucosinolates (GLS) are a group of plant thioglucosides present in plants of Cruciferae family. They are well known for their toxic effects (mainly as goitrogens) in both man and animals at high doses. In contrast at subtoxic doses, their hydrolytic and metabolic products act as chemoprotective agents against chemically-induced carcinogens by blocking the initiation of tumours in a variety of rodent tissues, viz. liver, colon, mammary gland, pancreas, etc. They exhibit their effect by inducing Phase I and Phase II enzymes, inhibiting the enzyme activation, modifying the steroid hormone metabolism and protecting against oxidative damages. Acid condensation products (like DIM) are more effective than their parent compounds (like I3C). Anticarcinogenesis caused by GLS is reviewed here.
Article
Full-text available
The glucosinolates are a large group of sulphur-containing glucosides found in brassica vegetables. After physical damage to the plant tissue, glucosinolates are broken down, by the endogenous enzyme myrosinase, releasing glucose and a complex variety of biologically active products. The most important and extensively studied of these compounds are the isothiocyanates. Glucosinolates can be degraded or leached from vegetable tissue during food processing, but thermal inactivation of myrosinase preserves some intact glucosinolates in cooked vegetables. Once ingested, any remaining intact glucosinolates may be broken down by plant myrosinase in the small intestine, or by bacterial myrosinase in the colon. Isothiocyanates are absorbed from the small bowel and colon, and the metabolites are detectable in human urine 2–3h after consumption of brassica vegetables. Isothiocyanates are potent inducers of Phase II enzymes invitro, and they have been shown to increase the metabolism and detoxification of chemical carcinogens invitro and in animal models. Some of these compounds also inhibit mitosis and stimulate apoptosis in human tumour cells, invitro and invivo. This second effect raises the possibility that in addition to blocking DNA damage, isothiocyanates may selectively inhibit the growth of tumour cells even after initiation by chemical carcinogens. Epidemiological evidence supports the possibility that glucosinolate breakdown products derived from brassica vegetables may protect against human cancers, especially those of the gastrointestinal tract and lung. To define and exploit these potentially anticarcinogenic effects it is important to understand and manipulate glucosinolate chemistry and metabolism across the whole food-chain, from production and processing to consumption.
Article
The formation of 5,11-dihydroindolo[3,2-b]carbazole, a polyaromatic hydrocarbon responsiveness-receptor agonist as well as an anti-initiator and promoter of carcinogenesis, from ascorbigen under conditions of chemical synthesis and during incubation with gastric juice at physiological conditions, is demonstrated. Ascorbigen, rather than indole-3-carbinol, is the most important indole derivative for the enzyme-inducing effects of dietary cruciferous vegetables. The concentration of ascorbigen in these vegetables is at least five times (in molar ratio) higher than that of indole-3-carbinol.
Article
Cruciferous vegetable extracts from freeze-dried cabbage (FDC), freeze-dried fermented cabbage (FDS), and acidified Brussels spl outs (ABS) were prepared by exhaustive extraction with ethyl acetate. Estrogenic and antiestrogenic effects of these extracts were analyzed. To identify whether the extracts are potential estrogen receptor (ER) ligands that can act as agonists or antagonists, the binding affinity of extracts for the ER was measured using a competitive radiometric binding assay. The extracts bound with low affinity to the ER, and the relative binding affinity is estradiol > FDS > FDC > ABS. These extracts were evaluated for their estrogenic and antiestrogenic activities in estrogen-dependent human breast cancer (MCF-7) cells using as endpoints proliferation and induction of estrogen-responsive pS2 gene expression, which was analyzed using Northern blot assay. At low concentrations (5-25 ng/mL) all of the extracts reduced 1 nM estradiol-induced MCF-7 cell proliferation. Extracts at 25 ng/mL also inhibited estradiol-induced pS2 mRNA expression. At higher extract concentrations (50 ng/mL-25 mug/mL), however, increased proliferation in MCF-7 cells was observed. Similarly, expression of the pS2 gene was induced by higher extract concentrations (0.25-25 mug/mL). The pure estrogen antagonist, ICI 182,780, suppressed the cell proliferation induced by the extracts as well as by estradiol and also the induction of pS2 expression by the extracts. The ER subtype-selective activities of FDC and FDS were analyzed using a transfection assay in human endometrial adenocarcinoma (HEC-1) cells. FDS acted as an ER alpha -selective agonist while FDC fully activated both ER-alpha and ER-beta. Growth of the ER-negative MDA-231 cells was not affected by the extracts or by estradiol. This study demonstrates that cruciferous vegetable extracts act bifunctionally, like an antiestrogen at low concentrations and an estrogen agonist at high concentrations.
Article
An active thioglucoside glucohydrolase extract was prepared from commercial mustard powder and its effect on the degradation of two pure glucosinolates was investigated. During reaction in a distilled water medium the pH of the solution decreased markedly and the ratio of products (isothiocyanate and nitrile) varied considerably. After 20–30 min, when the pH had fallen to ca 5.6, isothiocyanate production ceased whilst nitrile continued to be produced and in amounts which increased linearly with time for at least 40 min. This behaviour can be correlated with the changing pH of the medium. In controlled pH experiments it was confirmed that nitrile formation is favoured at lower pH levels and that the ratio of nitrile to isothiocyanate is directly related to the hydrogen ion concentration of the medium. No reason could therefore be found for the observed formation of nitrile in some natural systems at pHs greater than 7.
Article
An epithiospecifier protein present in turnip tissue gives rise to 1-cyano-epithioalkanes during autolysis. Volatile hydrolysis products are produced from glucosinolates during autolysis of seeds, seedlings and plant tissue more than 6 weeks after sowing.
Article
The content of individual glucosinolates in 32 samples of cabbage (representing 21 cultivars), 11 samples of Savoy cabbage (seven different cultivars), 33 samples of swede (16 cultivars) and nine samples of turnip (three cultivars) have been determined by gas chromatography. 2‐Propenyl, 3‐methylsulphinyl and 3‐indolylmethyl glucosinolates were the predominant compounds in both types of cabbage, with the Savoy cabbage showing a mean total glucosinolate content more than double that of white cabbage (209 vs. 90mg/100g fresh weight). The glucosinolate content of the swede and turnip samples was more complex, with 2‐hydroxy‐3‐butenyl‐glucosinolate predominating in swedes and this compound, 3‐butenyl‐and 2‐phenylethyl‐glucosinolates being the major components of turnip. The mean total glucosinolate contents of swede and turnip were 92 and 93 mg/100 g fresh weight. Compared to published data on American vegetables, the UK cabbage samples were much richer in glucosinolates and the UK swede and turnip samples poorer in glucosinolates. Swede rind was observed to be a particularly good source of indolyl glucosinolates, the anticarcinogenic properties of which are presently under investigation.
Article
The vacuum steam volatile oils of cooked cabbage, broccoli, and cauliflower were analyzed by the combination of capillary gas chromatography and mass spectrometry. Major components characterized that had not been previously reported in these vegetables included nonanal and octanol in cauliflower and broccoli and 3-methylthiopropyl cyanide in cauliflower and cabbage, 4-methylthiobutyl cyanide, 2-phenylethyl cyanide, and 2-phenylethyl isothiocyanate in all three vegetables. The most unusual compound characterized was CH3SCH2SSCH3. Odor thresholds in water solution were determined on the major compounds characterized.
Article
Bei der Bildung des Ascorbigens aus L-Ascorbinsure und 3-Hydroxymethylindol tritt eine C-Alkylierung am C-2 des Ascorbat-Ions ein, wobei sich 2 diastereomere Ascorbigene bilden.
Article
Volatiles produced in model systems consisting of a crude enzyme preparation from Brussels sprouts (Brassica oleraceae L var bullata subvar gemmifera DC), sinigrin, ascorbic acid and 2-mercaptoethanol were investigated using gas chromatography-mass spectroscopy. 2-Propen-1-yl isothiocyanate was the only breakdown product of sinigrin in the absence of 2-mercaptoethanol but in its presence 1-cyano-2,3-epithiopropane and small amounts of 2-propen-1-yl cyanide also were formed. The identification of the 1-cyano-2,3-epithiopropane was confirmed by comparison with a standard produced by autolysis of Crambe abyssinica L seed and with published mass spectra. The presence of 1-cyano-2,3-epithiopropane in volatile extracts of unblanched, frozen stored Brussels sprouts is also reported.
Article
The effect of processing of vegetables on ascorbigen formation, the ultimate fate of its transformation, their pharmacological evaluation are areas requiring detailed study using analytical methods capable of measuring various individual components. A reversed-phase chromatographic system for separation of ascorbigen, which is an indole containing a derivative of l-ascorbic acid, and its synthetic analogs with different substituents in the indole nucleus was developed. The isocratic chromatographic system was also developed for separation of ascorbigen and its transformation products in acidic media. Ascorbigen B which was previously described as the 2-epimer of natural ascorbigen was shown by HPLC to be a mixture of compounds, where natural ascorbigen ‘dimer’ was the major component, and natural ascorbigen and its ‘trimer’ were the minor components. To determine the content of ascorbigen and its transformation products in extracts of fresh or sour cabbage a reversed-phase chromatographic system with gradient elution was developed, with l′-methylascorbigen as an internal standard. Extracts of fresh or sour cabbage contained the ascorbigen (2·4–5·5 mg per 100 g fresh weight), as the major component and ascorbigen ‘dimer’ (0·1–0·3 mg per 100 g fresh weight), ascorbigen ‘trimer’ (0·1–0·3 mg per 100 g fresh weight), 3-hydroxymethylindole (0·2–0·3 mg per 100 g fresh weight) and (indole-3-yl)acetonitrile (0·1–0·5 mg per 100 g fresh weight) as the minor components.
Article
Phytochemicals, especially the secondary metabolites synthesized by plants, play key roles in human nutrition, health, wellness, and disease prevention. Some phytochemicals may be harmful to human health. For example, two closely related 4-methylsulfinylbutyl glucosinolate [glucoraphanin] hydrolysis products from broccoli (Brassica oleracea L. var. Botrytis), 1-isothiocyanato-4-(methyl-sulfinyl)butane (sulforaphane) and 5-(methylsulfinyl)pentanenitrile (sulforaphane nitrile), may have beneficial or deleterious effects on human health, respectively. Preliminary studies using a gas chromatography/mass spectrometry (GC/MS) system operated under split/splitless conditions revealed that ≈80% of sulforaphane was degraded to 3-butenyl isothiocyanate. A GC/MS method was developed wherein thermal degradation of sulforaphane was reduced to 5% through the use of an appropriate injector liner and precise control of the carrier gas flow rates. The method provides a simple, rapid technique for the analysis of both sulforaphane and sulforaphane nitrile that is suitable for routine screening of plant materials.
Article
Hydrolysis/autolysis of the glucosinolates found in wild and cultivated cruciferous plants can yield a variety of nitrogenous compounds for the alkyl or aryl moiety. These products include nitriles, isothiocyanates and oxazolidinethiones, all of which may present potential hazards in foods and feeds. More than 70 glucosinolates are known, and almost all the hydrolysis products are amenable to analysis by gas chromatography. The reaction can proceed in different ways, depending upon the conditions of hydrolysis or treatment of the plant during harvest or storage, and confirmation of the identifications made by retention data is sometimes needed. Gas chromatography-mass spectrometry can usually provide this additional structural information. Spectra of alkyl or aryl nitriles and isothiocyanates that contain other functional groups (hydroxyl, episulphide, methylthio, sulphinyl, sulphonyl) and oxazolidinethiones are presented and discussed.
Article
Dichloromethane extracts of juices from fresh cabbages, including four known (Brutus, Galaxy, Bentley, Structon) and two unknown cultivars, were analyzed by X-MS for the presence of sinigrin degradation products. Allyl isothiocyanate (AITC), which has been reported to be the important aroma compound of freshly disrupted cabbage was not detected in any of the dichloromethane extracts of cabbage juice. Instead, 1-cyano-2,3-epithiopropane, which is one of the isomers of AITC, was the primary volatile compound in all cabbage extracts. AITC was detected in relative trace concentration only when cabbage juice was injected into the GC, using a wide bore, packed column. Thus, the relative importance of AITC and 1-cyano-2,3-epithiopropane to the aroma of freshly disrupted cabbage should be considered.
Article
The mechanisms by which brassica vegetables might decrease the risk of cancer are reviewed in this paper. Brassicas, including all types of cabbages, broccoli, cauliflower and Brussels sprouts, may be protective against cancer due to their relatively high glucosinolate content. Glucosinolates are usually broken down through hydrolysis catalyzed by myrosinase, an enzyme that is released from damaged plant cells. Some of the hydrolysis products, viz. indoles and isothiocyanates, are able to influence phase 1 and phase 2 biotransformation enzyme activities, thereby possibly influencing several processes related to chemical carcinogenesis, e.g. the metabolism, DNA-binding and mutagenic activity of promutagens. A reducing effect on tumor formation has been shown in rats and mice. The anticarcinogenic action of isothiocyanates and indoles depends upon many factors, such as the test system, the target tissue, the type of carcinogen challenge and the anticarcinogenic compound, their dosage, as well as the timing of the treatment. Most evidence concerning anticarcinogenic effects of glucosinolate hydrolysis products and brassica vegetables has come from studies in animals. Animal studies are invaluable in identifying and testing potential anticarcinogens. In addition, studies carried out in humans using high but still realistic human consumption levels of indoles and brassica vegetables have shown putative positive effects on health.
Article
Analysis of Lepidium sativum seeds showed the presence of allyl, 2-phenethyl and benzyl glucosinolates, the first two being reported for the first time from this source. The effects of temperature, pH of the extraction medium and the length of time allowed for autolysis were assessed on the benzyl glucosinolate degradation products in seed extracts. In particulàr benzyl thiocyanate was not produced at higher temperatures but at ambient and lower temperatures it exceeded isothiocyanate. Nitrile was always the major product under the conditions studied, ever at pH levels as high as 7.4. Five new possible benzyl glucosinolate degradation products were detected and evidence is presented that benzaldehyde and benzyl alcohol could be secondary products formed thermally from isothocyanate and thiocyanate, respectively. Benzyl mercaptan and benzyl methyl sulphide also appear to be thermally produced.
Article
The purification of the omega-(methylsulfinyl)alkyl glucosinolate hydrolysis products 1-isothiocyanato-3-(methylsulfinyl)propane (IMSP), 1-isothiocyanato-4-(methylsulfinyl) butane (IMSB), 4-(methylsulfinyl)-butanenitrile (MSBN), and 5-(methylsulfinyl) pentanenitrile (MSPN) from the seeds of broccoli and Lesquerella fendieri (Gray) S. Watson is described. The procedure uses solvent extraction of autolyzed defatted seed meals, followed by purification of the hydrolysis products using gel filtration chromatography and reversed-phase high-performance liquid chromatography (HPLC). Purity and confirmation of the compounds were monitored and verified using gas chromatography with flame ionization detection (GC-FID), thin-layer chromatography (TLC), gas chromatography-mass spectroscopy (GC-MS), and nuclear magnetic resonance (NMR). The techniques are useful for the preparative-scale isolation of structurally related glucosinolate hydrolysis products arising from omega-(methylsulfinyl)alkyl glucosinolates and should facilitate more extensive studies into the biological effects of these naturally occurring compounds.
Article
The hydrolysis of the glucosinolates, sinigrin, gluconapin, glucobrassicanapin, progoitrin, glucotropaeolin, sinalbin, gluconasturtiin, glucobrassicin, and 4-hydroxyglucobrassicin, by myrosinase from white mustard (Sinapis alba) or acid was examined. While all glucosinolates were hydrolyzed by myrosinase, only 4-hydroxyglucobrassicin, glucosinalbin, gluconasturtiin, glucobrassicin, and progoitrin were partially hydrolyzed by acid (pH 2). When intact glucosinolates or myrosinase-treated glucosinolate products were treated with nitrite, only glucobrassicin and 4-hydroxyglucobrassicin formed N-nitroso compounds. The nitrosated products of myrosinase-treated glucobrassicin alone were mutagenic and induced about 400 Salmonella typhimurium TA100 revertants/mu-mol. The enzymic breakdown products of the alkyl and aryl glucosinolates were cytotoxic, but this activity was not affected by subsequent nitrite treatment. Given the levels at which indole glucosinolates occur in brassica vegetables, these findings suggest that their contribution to the observed mutagenic potential of these vegetables after nitrite treatment will be marginal. Further work is, however, needed to identify the exact chemical natures of both the N-nitroso compounds formed in nitrite-treated brassicas and their naturally occurring precursors.
Article
Knowledge of glucosinotate (GS) content in cabbage (Brassica oleracea) is needed to establish levels at which these compounds or their enzymically released products are consumed. New methods of analysis for individual and total GS were applied to 12 open-pollinated and 10 hybrid varieties. Total glucosinolates in cabbage as harvested ranged from 299 to 1288 ppm. Of the 12 GS's determined, those found in the greatest amount were: two 3-indotylmethyl GS's (18 to 63 ppm as thiocyanate ion); allyl GS [4 to 146 ppm as allyl isothiocyanate (ITC)]; 3-methyisulfinylpropyl GS (30 to 164 ppm as ITC); 4methylsulfinylbutyl GS (0.2 to 119 ppm as ITC). The last two have not been quantitated previously in edible cabbage. Goitrin content ranged from 1.2 to 26 ppm. Significant differences among varieties were found and are attributed to genetic variability. Variation in GS content from head to head within a variety was greater in the open-pollinated than in the hybrid varieties.
Article
The addition of L-ascorbate or 2-mercaptoethanol to aged crambe seed meal tends to restore the fresh meal pattern of epi-progoitrin hydrolysis to nitriles instead of (R)-goitrin. Neither of these reducing agents has an effect on the breakdown of epi-progoitrin to goitrin by an insoluble particulate thioglucosidase from crambe meal. The addition of ferrous ion to the insoluble particles results in the conversion of epi-progoitrin to (2S)-1-cyano-2-hydroxy-3-butene instead of (R)-goitrin over a range from pH 3.9 to 6.7.
Article
This review surveys the occurrence, analysis, and properties of glucosinolates and derived compounds in plants and products intended for humans and animal consumption. The paper, which includes references published in 1981, is also intended to compliment existing reviews on the chemistry of these sulfur‐containing natural products. Particular emphasis is placed upon members of the Brassica family because of their importance as vegetables, condiments, oilseeds, and animal feedingstuffs. Since much of the work considered here relates to glucosinolate decomposition products, biochemical information concerning the nature, occurrence, and properties of the glucosinolate‐degrading enzyme, myrosinase, is considered in Section III. The methods available for the chemical analysis of glucosinolates and their various breakdown products are discussed critically. Factors affecting the glucosinolate content of plants and plant products arc outlined in Section VII. Particular emphasis is placed upon the effect of processing on the concentration and nature of breakdown products and on the myrosinase activity. The role of glucosinolate breakdown products on flavor development is examined in Section VIII. The more general effects, both beneficial and adverse, of these compounds in food are discussed in Section X. Since such effects in animal feedingstuffs have been the subject of regular reviews, these are considered here only briefly. Contraindications in the literature are pointed out, areas which have been inadequately explored are highlighted, and suggestions are made for future research.
Article
Three varieties of cabbage, Roundup, Sanibel, and TBR Globe, were commercially processed into sauerkraut. The aglucon products from two of the three glucosinolates abundant in kraut cabbage were measured at intervals from fresh cabbage to canning of the sauerkraut. Within the first 2 weeks of fermentation, all the glucosinolates were hydrolyzed. Thiocyanate ion and 1-cyano-3-methylsulfinylpropane, the aglucon products measured, varied little from 2 weeks of fermentation to finished sauerkraut. In the finished kraut, thiocyanate ion ranged from 9 to 17 ppm and 1-cyano-3-methylsulfinylpropane ranged from 16 to 25 ppm. No isothiocyanates or goitrin were present. No nitriles from allyl glucosinolate were found.
Article
Searches for the natural compounds that determine the anticarcinogenic properties of a cruciferous-vegetable diet, revealed the products of alkaloid glucobrassicin biotransformations; among these, ascorbigen, an indole-containing derivative of L-ascorbic acid, was found to be the most abundant. Study of chemical properties of ascorbigen showed that it is capable of different transformations in acidic (including gastric juice) and slightly alkaline (including blood) media. The stable and unstable products of ascorbigen transformation determine the biological properties of the compound. The most important product of ascorbigen transformation in gastric juice is 5,11-dihydroindolo[3,2-b]-carbazole, with a binding affinity to the Ah receptor only 3.7 x 10(-2) lower than that of tetrachlorodibenzodioxin. This compound may be responsible for modifying P450 enzyme activities. Ascorbigen and its analogs are available synthetically. Their biological evaluation showed that some of the compounds of these series are immunomodulators. The most active is N-methylascorbigen, which demonstrates therapeutic effects (inhibition of tumor growth, protection of animals from bacterial and viral infections). The immunomodulatory activity of natural ascorbigen may be an additional factor of importance for the anticarcinogenic properties of a cruciferous-vegetable diet.
Article
Indole-3-carbinol (I3C) is a major component of Brassica vegetables, and diindolylmethane (DIM) is the major acid-catalyzed condensation product derived from I3C. Both compounds competitively bind to the aryl hydrocarbon (Ah) receptor with relatively low affinity. In Ah-responsive T47D human breast cancer cells, I3C and DIM did not induce significantly CYP1A1-dependent ethoxyresorufin O-deethylase (EROD) activity or CYP1A1 mRNA levels at concentrations as high as 125 or 31 microM, respectively. A 1 nM concentration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced EROD activity in these cells, and cotreatment with TCDD plus different concentrations of I3C (1-125 microM) or DIM (1-31 microM) resulted in a > 90% decrease in the induced response at the highest concentration of I3C or DIM. I3C or DIM also partially inhibited (< 50%) induction of CYP1A1 mRNA levels by TCDD and reporter gene activity, using an Ah-responsive plasmid construct in transient transfection assays. In T47D cells cotreated with 5 nM [3H]TCDD alone or in combination with 250 microM I3C or 31 microM DIM, there was a 37 and 73% decrease, respectively, in formation of the nuclear Ah receptor. The more effective inhibition of induced EROD activity by I3C and DIM was due to in vitro inhibition of enzyme activity. Thus, both I3C and DIM are partial Ah receptor antagonists in the T47D human breast cancer cell line.
Article
Modulation of cytochrome P4501A1 (CYP1A1) activity is a mechanism whereby indoles present in cruciferous vegetables could affect the metabolism of xenobiotics. Ascorbigen (ASG) is the predominant indole formed during the degradation of glucobrassicin, although the mechanism by which ASG modulates CYP1A1 activity is not known. The major focus of this study was to examine the mechanism of CYP induction by ASG using a murine hepatoma-derived cell line (Hepa 1c1c7). ASG was shown to induce the activity of 7-ethoxyresorufin O-deethylase, a marker for CYP1A1, in a concentration-responsive manner with a maximum induction at 700 microM. Maximum ASG induction after 24-hr treatment was 7% of maximal CYP1Al activity induced by the well-known potent CYP1A1 inducer, indolo[3,2-b]carbazole (ICZ) (1 microM), and the EC50 values differed by 2-fold. The CYP1A1 activity increased continuously up to 72 hr, where ASG showed an induction efficiency in the same range as for the positive control (1 microM ICZ) after 24 hr, whereas the CYP1A1 protein level, measured by Western blot analysis, was maximally induced after 24 hr. ASG significantly inhibited CYP1A1 activity in whole cells at concentrations above 1 microM. ASG increased the chloramphenicol acetyl transferase (CAT) activity via a CAT reporter construct containing a dioxin-responsive element in Hepa 1c1c7 cells, indicating involvement of the aryl hydrocarbon receptor. ASG was shown to be transformed into ICZ, or a compound with the same chromatographic mobility as ICZ, in the medium. Taken together, the results indicate that ASG inhibits CYP1A1 activity at low concentrations, but induces the same activity at higher concentrations.
Article
Individual glucosinolates (GLS) were determined in vegetables of three Cruciferae species: Brassica oleracea L. (white cabbage, red cabbage, Savoy cabbage, Brussels sprouts, cauliflower, kale, kohlrabi), Brassica rapa L. (turnip), and Raphanus sativus L. (red radish, black radish, and white radish) produced in two years. The cultivars were compared for the contents of total-, indole-, and aliphatic GLS. In both years, the total content of GLS was highest in black radish, and all examined R. sativus vegetables contained the greatest amount of aliphatic GLS. Neither the level nor the identity of GLS differentiated among the vegetables of the other cultivars grown in the same year. Comparison of the GLS contents of the same cultivar in two production years, which differed in temperature and rainfall rate, showed that low average 10-day rainfall and high average temperature during the vegetation period significantly increased the GLS content of vegetables. This suggests that the year x cultivar interaction modified the GLS content of vegetables.
Article
Several epidemiologic studies suggest that consumption of cruciferous vegetables may be particularly effective (compared with total fruit and vegetable consumption) in reducing cancer risk at several organ sites. Crucifers that are widely consumed are especially rich in glucosinolates, which are converted by plant myrosinase and gastrointestinal microflora to isothiocyanates. A number of isothiocyanates and a limited number of glucosinolates that were examined effectively block chemical carcinogenesis in animal models. Many isothiocyanates are also potent inducers of phase 2 proteins. Substantial evidence supports the view that phase 2 enzyme induction is a highly effective strategy for reducing susceptibility to carcinogens. This conclusion has recently received strong molecular support from experiments on mice in which the specific transcription factor, nrf2, which is essential for induction of phase 2 proteins, was deleted. In these knock-out mice, the basal levels of phase 2 enzymes are very low and not inducible. Accordingly, these mice are much more susceptible than their wild-type counterparts to benzo[a]pyrene forestomach carcinogenesis and are not protected by phase 2 inducers. These experiments provide very strong evidence for a major role of phase 2 enzymes in controlling the risk of exposure to carcinogens. An increasing number of phase 2 proteins that exert a variety of protective mechanisms are being identified. Thus, in addition to detoxifying electrophiles, these proteins exercise versatile, long-lasting and catalytic antioxidant protection.
Article
Indole-3-carbinol (I3C), found in cruciferous vegetables, has been shown to suppress tumorigenesis at estrogen-responsive sites. This effect may be mediated through modification by I3C of the cytochrome P450 (CYP) complement and activities leading to estrogen detoxication. In this study, we examined the effects of 4- and 10-day treatments of female Sprague-Dawley rats with I3C at 5, 25, and 250 mg/kg body weight, administered by oral gavage, on CYP mRNA expression in the liver and mammary gland, CYP-dependent activities, and the metabolism of 17beta-estradiol (E2) and estrone (E1) by liver microsomes. The mRNA transcripts for hepatic CYP1A1, 1B1, and 2B1/2 and mammary CYP1A1 were up-regulated after treatment with I3C at 250 mg/kg. However, the level of expression of CYP1B1 in the liver was lower than that of other CYPs. In the mammary gland, CYP1B1 mRNA levels were unaltered by treatment and similar to those of I3C-induced CYP1A1. Hepatic P450 probe activities indicative of induction of CYP1A1, 1A2, and 2B1/2 were increased by I3C in a dose-dependent manner. Treatment with I3C at 250 mg/kg increased the capacity of liver microsomes to metabolize E2 to 2-OH-E2, 2-OH-E1, 6alpha-OH-E2, 6beta-OH-E2, estriol, and 15alpha-OH-E2, and E1 to 2-OH-E1, 2-OH-E2, 6(alpha+beta)-OH-E1, and 6alpha-OH-E2. The magnitudes of increases of CYP-dependent activities and rates of estrogen metabolite formation achieved with I3C at 250 mg/kg were smaller after ten than four treatments. The increased rates of formation of 6alpha-OH-E2, 6beta-OH-E2, and 15alpha-OH-E2 from E2 were also detected after treatment with I3C at 25mg/kg, and, except for increased 6beta-OH-E2 from E2, no other changes in E2 or E1 metabolism occurred after treatment with I3C at 5mg/kg. The data indicate that alterations in the CYP complement and, thus, metabolite composition from E2 and E1 are I3C dose- and treatment duration-dependent, and suggest that potential biological activity of I3C administered at low doses to rats may not involve changes in estrogen metabolism.
Article
The formation of plant-derived biomolecules during sauerkraut fermentation was studied. Cabbage was fermented with a starter culture, and the results were compared to the results of spontaneous fermentation. The concentration of flavonoids and glucosinolates was analyzed by HPLC, and that of the glucosinolate breakdown products, by GC-MS. Of the 20 different flavonoids tested, only kaempferol was found (0.9 mg/ kg FW, fresh weight). The content of kaempferol remained constant in the cabbage fiber matrix over the fermentation process. The nitrite concentration was below the detection limit in both fermentations. The total glucosinolate content in the raw material was 3.71 micro mol/g DW, dry weight. Glucosinolates were totally decomposed in both fermentations during two weeks, and different types of breakdown products were formed. Isothiocyanates, indole-3-carbinol, goitrin, allyl cyanide, and nitriles were determined in the fermented cabbage. Isothiocyanates and allyl cyanide were the predominant breakdown products in both fermentations. Sulforaphane nitrile and goitrin were found only in small quantities in the end products.
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