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Changes in total phenolic and monomeric anthocyanin composition and antioxidant activity of three varieties of sorrel (Hibiscus sabdariffa) during maturity

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Abstract

Three varieties of sorrel (Hibiscus sabdariffa) were analyzed for total phenolic, monomeric anthocyanins and antioxidant activity at five stages of maturity. The varieties designated traditional red (TRED), early bearing red (ERED) and white (WHTE) were sampled at the pre-flowering stage, as well as 3 days, 7 days, 21 days and 35 days after flowering. The total phenolic composition ranged from 5 to 24 mg/g and, while found in all varieties, was highest for TRED and ERED. Anthocyanins were only observed in the red varieties and ranged from 0.5 to 3.5 mg/g. The levels of both total phenolics and monomeric anthocyanins fluctuated, initially declining then increasing with maturation. The three sorrel varieties exhibited antioxidant activity, inhibiting lipid peroxidation between 69 and 79%. Increasing maturity at harvest tended to increase antioxidant activity for all varieties. A linear relationship existed between antioxidant activity and stage of maturity (r = 0.59). This research has implications for the sorrel industry as the antioxidant phytonutrients of sorrel could add value to sorrel currently produced and consumed.

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... The phenolic content in the plant consists mainly of anthocyanins like delphinidin-3-glucoside, sambubioside, and cyanidin -3 -sambubioside mainly contributing to their antioxidant properties [5] and the amount of cyaniding -3 -sambubioside is lower than delphinidin -3 -sambubioside [6]. Ascorbic acid also has antioxidant properties [7]. Anthocyanins and organic acids in roselle had the ability as an antioxidant [8]. ...
... Anthocyanins and organic acids in roselle had the ability as an antioxidant [8]. The antioxidant properties rely on pH (2)(3)(4)(5)(6)(7) in which the ability of antioxidant decreases when pH increases [9]. ...
... The lowest TPC values were in se'i treated with roselle extract 8% (RCE 2 ). The roselle calyces contain some bioactive compounds in which have antimicrobial activity such as organic acids, anthocyanins, phenolic acids and alkaloids [7]. The main organic acid in roselle calyces are citric acid, malic acid and others, result in low pH approximately 2 -2.5 [28], and contribute to antimicrobial activity [29]. ...
... Roselle (Hibiscus sabdariffa L.) is a plant that belongs to family Malvaceae, its chalices are recognized as an important source of phenolic compounds [1][2][3]. Mexico is one the main roselle producer countries, where it is widespread consumed in beverage. This beverage is obtained by thermal infusion of dehydrated chalices [3]. ...
... This beverage is obtained by thermal infusion of dehydrated chalices [3]. It has been used in traditional medicine for treatment of some diseases such as: antibacterial, antifungal, hypocholesterolemic, diuretic, antihypertensive, against inflammation among others [3], because of its antioxidant properties [1,2]. Roselle chalices are used worldwide for drinks production and as additives in cosmetics and pharmaceuticals [4]. ...
... There are few studies on roselle cultivars having as main characteristic their different pigmentation degree. Christian and Jackson [1] studied roselle grown in Jamaica, reporting that dark roselle chalices presented the highest anthocyanins content and antioxidant activity, followed by red chalices, while in the white ones, these compounds were not detected; these results were similar to reported by other authors [2,5]. Mexico is one of the main roselle producer countries and recently breeding programs have generated new cultivars with different pigmentation levels of which only their volatile compounds have been evaluated so far [5]. ...
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Roselle is a plant that accumulates anthocyanins significantly, hence its importance as food coloring and as a source of antioxidant compounds for human health. This study was aimed to determine phenolic composition and antioxidant capacity of methanolic extracts, and beverages obtained from native roselle cultivars in Mexico (Negra, Sudan, Rosa and Blanca) with different degrees of pigmentation, and to establish the color-composition relationship. Chromatographic methods were used to determine phenolic compounds: flavanols, flavonols, benzoic, hibiscus and phenolic acids as well as two main anthocyanins (cyanidin 3-sambubioside and delphinidin 3-sambubioside). The antioxidant capacity was evaluated by ABTS and FRAP assays. Tristimulus colorimetry showed to be a useful technique to determine the color-composition relationship, leading to equations that allowed to predict anthocyanin content of roselle (R > 0.84). Also, a stepwise linear discriminant analysis (SLDA) was developed in order to classify roselle cultivars. The obtained mathematical model could be an important tool to be used in colorimetric characterization of functional compounds used in food processing.
... The plant is an important annual crop widely cultivated in tropical and subtropical areas including Sudan, Eastern Taiwan, and Thailand [1,2]. The high antioxidant activity showed by roselle has been directly associated to their phenolic, flavonoid, anthocyanin and ascorbic acid content [3][4][5][6][7]. Different pharmaceutical uses of roselle have been developed around the world. ...
... As we anticipated, the white roselle showed negligible level of anthocyanins (0.03 c ± 0.00 mg cyanidin/100 g). These results in agreement with literature since these compounds are accountable for the red color of the roselle plant [7]. Currently, it is accepted that flavonoids originated from plant sources such as roselle are relevant not only for industrial purposes and organoleptic characteristics, but also because of their prospective health stimulating properties [35]. ...
... It was evident that the TPC in white roselle was less than the red type. Similar results were reported in white (12.79 mg/g) and red (23.12 mg/g) Jamaican Hibiscus [7]. The higher total phenolic compounds of Al-Rahad, Al-Fashir, Al-Gezira could be due to the brilliant red color of the flowers, of which phenolic compounds are the part of these components [35]. ...
Article
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The antioxidant properties of the water extract of Hibiscus sabdariffa L. as well as their aroma profile were investigated. The samples analyzed were three red (Al-Rahad, Al-Fashir, Al-Gezira) and one white varieties. Total phenolic content, total flavonoid content, total anthocyanin content, ferric reducing antioxidant power and radical scavenging activity (RSA %) were measured spectrophotometrically. The red varieties of Karkade showed better overall antioxidant properties and aroma profile compared to the white variety. Conversely, the white H. sabdariffa might also be used in antioxidants applications, as its extract exhibited the highest RSA % compared to other varieties. Nineteen volatile compounds were detected in the H. sabdariffa extracts, including aldehydes, alcohols, ketones, esters and phenol. Partial least squares regression (PLSR) was applied to determine the relationship between sensory descriptors and instrumental data. PLSR result showed a good relationship between sensory analysis and instrumental data (t1 and t2 = 94.63%). This indicated that gas chromatography-mass spectrometry (GC/MS) can be used as suitable tools to predict the aroma quality of H. sabdariffa.
... The phenolic content in the plant consists mainly of anthocyanins like delphinidin-3-glucoside, sambubioside, and cyanidin -3 -sambubioside mainly contributing to their antioxidant properties (Aurelio et al., 2007) and the amount of cyaniding -3 -sambubioside is lower than delphinidin -3 -sambubioside (Peng- Kong et al., 2002). Ascorbic acid also has antioxidant properties (Christian and Jackson, 2009). Anthocyanins and organic acids in roselle had the ability as an antioxidant (Bozkurt and Belibag (2009). ...
... Anthocyanins and organic acids in roselle had the ability as an antioxidant (Bozkurt and Belibag (2009). The antioxidant properties rely on pH (2)(3)(4)(5)(6)(7) in which the ability of antioxidant decreases when pH increases (Sukhapat et al., 2004). ...
... The lowest TPC values were in se'i treated with roselle extract 8% (RCE2). The roselle calyces contain some bioactive compounds in which have antimicrobial activity such as organic acids, anthocyanins, phenolic acids and alkaloids (Christian and Jackson, 2009). The main organic acid in roselle calyces are citric acid, malic acid and others, result in low pH approximately 2 -2.5 (Ali et al., 2005), and contribute to antimicrobial activity (Morales-Cabrera et al., 2013). ...
... The colour of the calyx of this plant, known as roselle, varies from light to intense red and is related to its phytochemical content. Dark calyces have higher anthocyanin contents than do light calyces [6]. Delphinidin-3-sambubioside and cyanidine-3-sambubioside have been reported to be the two main anthocyanins in roselle and delphinidin-3-glucoside and cyanidin-3-glucoside are found in smaller amounts [7]. ...
... In general, the colour of the roselle calyx is very varied and can present values of luminosity between 29 and 49, chromaticity between 18 and 27, and hue angle between 13 and 28 [2], which correspond to calyces of light red, deep red, and dark brown red. However, each variety of roselle has market value owing to its visual quality, size, anthocyanin content, and chemical characteristics such as acidity and aroma [6]. ...
Article
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Abiotic factors can alter the chemical profile of crops and the number of compounds they contain. In this study, the anthocyanin and anthocyanidin contents, determined by ultra-performance liquid chromatography (UPLC-MS/MS), and the colour attributes of the calyces of three cultivars of Hibiscus sabdariffa subjected to three water stress regimes during the stage of physiological maturity were investigated. The total anthocyanin content in calyx increased relative to the control content under a 65% moisture irrigation regime. Among the cultivars, UAN16-2 showed the greatest increases in the contents of cyanidin, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside, and cyanidin 3-O-sambubioside. The content of cyanidin 3-O-sambubioside showed the greatest increase, increasing by 55% relative to the control level. The contents of these compounds are correlated with colour attributes such as luminosity. Water stress under the 33% moisture condition during plant development led to decreased anthocyanin contents in all of the roselle cultivars.
... An important source of anthocyanins is roselle (Hibiscus sabdariffa L.) calyces, which are consumed mainly as refreshing drinks (Prenesti, Berto, Daniele, & Taso, 2007). The color of Hibiscus calyces varies from yellowish green to deep red and is related to the content of these phytochemicals (Christian & Jackson, 2009). Thus, the varieties of dark calyces have an anthocyanin concentration five to seven times greater than that of clear calyces; on the other hand, the green and yellow varieties lack these compounds (Salinas-Moreno, Zúñiga-Hernández, Jiménez-de la Torre, Serrano-Altamirano, & Sánchez-Feria, 2012). ...
... Como fuente importante de antocianinas destacan los cálices de jamaica (Hibiscus sabdariffa L.); las cuales se consumen principalmente como bebidas refrescantes (Prenesti, Berto, Daniele, & Taso, 2007). El color de los cálices de Hibiscus varía desde verde amarillento hasta rojo intenso, y se encuentra relacionado con el contenido de estos fitoquímicos (Christian & Jackson, 2009). Así, las variedades de cálices oscuros contienen entre cinco y siete veces más concentración de antocianinas que las de cálices claros; por su parte, las variedades verdes y amarillas carecen de estos compuestos (Salinas-Moreno, Zúñiga-Hernández, Jiménez-de la Torre, Serrano-Altamirano, & Sánchez-Feria, 2012). ...
Article
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The he consumption of nutraceutical foods, such as extracts of roselle (Hibiscus sabdariffa L.) calyces, improve health and prevent several diseases, attributable in part to the activity of their anthocyanins. Exposure of plants to high concentrations of some heavy metals stimulates the synthesis of anthocyanins; therefore, the objective of this study was to determine the effect of foliar application of Zn and Cu at high concentrations on calyx yield, anthocyanin content and physicochemical characteristics in three roselle genotypes. The Criolla Guerrero, Criolla Michoacán and Reina Roja genotypes were sown under rainfed conditions. The foliage of the plants in vegetative stage was sprayed with Zn and Cu solutions separately, making in total four applications of 300 mg∙L-1. Both elements reduced the calyx yield in Criolla Guerrero, did not modify it in Criolla Michoacán and in Reina Roja the Zn increased the yield by 15.9 %, achieving 1,232 kg∙ha-1. In all genotypes, the applications of these elements improved the content of anthocyanins and titratable acidity and decreased the content of ascorbic acid. Criolla Michoacán had the highest increase in anthocyanins, with 187 % Cu and with 175 % Zn; however, this genotype did not exceed the final anthocyanin content in Reina Roja, which with Cu recorded 22.68 mg∙g-1. Therefore, the application of these elements is an alternative to increase the content of anthocyanins, to which some nutraceutical qualities are attributed. (18) Rendimiento y concentración de antocianinas en Hibiscus sabdariffa L. con 5 aplicación foliar de micronutrimentos. Available from: https://www.researchgate.net/publication/323145256_Rendimiento_y_concentracion_de_antocianinas_en_Hibiscus_sabdariffa_L_con_5_aplicacion_foliar_de_micronutrimentos [accessed May 24 2018].
... Antioxidants assist in preventing cell damage by limiting the formation of free radicals, acting as free radical scavengers and promoting their decomposition (16). Hibiscus sabdariffa and Citrus sinensis have gained attention for their antioxidant activity (17)(18)(19). Sorrel and citrus by-product extracts possessed similar antioxidant activities (141.57 µmol/g ± 5.27 and 139.77 ...
... Determination of antioxidant activity (by the three techniques employed), phenolic content, and that of the monomeric anthocyanins of the aqueous extracts of the roselle varieties analyzed show that the red varieties present greater activity and concentration of bioactives, while green varieties present less activity. The latter coincides with that reported by Juliani et al. (2009), who analyzed phenolic compounds, ABTS• + cation scavenging capacity, and anthocyanin content in roselle varieties of different colors in Senegal, and the results of Christian and Jackson (2009), who determined the content of anthocyanins, phenolics, and the activity on DPPH• of three roselle varieties (dark red, red, and green). With regard to the aqueous extracts' AA content, the higher concentration is found in varieties with darktoned calyces (red and purple) and the lower one, in the green-colored varieties; this differs significantly with that previously reported by Salinas-Moreno et al. (2012) and Babalola et al. (2001); both investigations concluded that light-toned calyces contained more AA than dark-toned 1206 ...
Article
Roselle (Hibiscus sabdariffa L.) also called roselle fruit or flower of jamaica is a plant used in the traditional medicine due to its wealth of bioactive compounds. These compounds confer beneficial health benefits on it in aqueous infusions prepared with the blossoms of the jamaica flower. In the present study, we determined the antioxidant activity of 64 roselle varieties and quantified the following bioactive compound contents: phenolic; monomeric anthocyanins, and ascorbic acid. The results show that highest antiradical scavenging activity and reductor capacity belonged to varieties with dark-red calyces. Similarly, we found that the bioactive compound concentration increased as the pigmentation of the fresh calyces intensified. Finally, our results demonstrated that the aqueous extracts' antioxidant activity is correlated with the bioactive compound concentration, this correlation greater with the content of ascorbic acid.
... The mean values of TMA varied from 3.07 to 3.82 mg/g extract on a dry basis for the hibiscus calyces extracts Fig. (1A), where the increase in the stirring speed and the temperature increased the TMA concentrations. These values are in agreement with Christian and Jackson [32] that reached mean values from 1.8 to 3.5 mg/g extract on a dry basis for TMA using organic solvents in the extraction. Thus, when used to ideal conditions in the hibiscus aqueous extraction process, it is possible to achieve similar levels of total monomeric anthocyanins compared with extraction with organic solvents. ...
Article
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Introduction Hibiscus calyces are important sources from anthocyanins and pigments. The recovery of these bioactive compounds using non-organic solvents becomes very attractive for the food industry. Methods For this reason, the separation of phenolic compounds by acidified aqueous extraction from hibiscus calyces was studied. The experiments were conducted by a fractional factorial design. Result and Conclusion Four factors were evaluated: temperature, time, stirring speed and enzyme concentration. The extracts produced were subjected to analysis of color ( L* , a* , b* and Chroma ), total monomeric anthocyanins, antioxidant capacity by ABTS and fourteen phenolic compounds were quantified. The results showed that the best condition to obtain hibiscus calyces extract was using an enzyme concentration of 50 µL/1000 g hibiscus extract, 400 rpm of stirring speed at 55 ºC by 4 hours of extraction, that corresponded to concentrations of 17595, 7516, 2568 μg/g, expressed on a dry basis, for total phenolic compounds, delphinidin 3-sambubioside and cyanidin 3-sambubioside, respectively, and antioxidant capacity measured by ABTS of 7.8 µmol of Trolox equivalent per gram.
... plant reduces cholesterol, Gurrola-Díaz, et al. [4] lipid, Kuriyan, et al. [5] blood viscosity [6] and blood pressure [7]. Furthermore, this plant have also been known to have anti-hypertension, Mohagheghi, et al. [8] antidiabetic, Mozaffari-Khosravi, et al. [9] antioxidant, Ochani and D'Mello [10]; Christian and Jackson [11] antipyretic, anticancer, antiseptic [12] and hepatoprotective [13] activities, the main compounds found in calyx of Hibiscus sabdariffa are citric acid, malic acids, anthocyanins, flavonoids and glycosides [14] caffeic acid, polyphenolic acid, protocatechuic acid, catechin, gallocatechins [15]. The nutritional and medical importance of this plant is believed to be due to the present of these phytochemical compounds. ...
... Ethanol is a good solvent for polyphenol extraction and is safe for human consumption (Shi et al., 2005). The current study agrees with results found by Christian and Jackson (2009) and Anokwuru et al. (2011) which were 5.25 and 27.6 mg/g of ethanol extracts of H. sabdariffa L. calyx, respectively. However, a research conducted by Koffi et al. (2010) indicated that ethanol was the best solvent for the extraction of phenol in the Ivorian plant. ...
Article
Full-text available
The present study investigated the total content of phenolic compounds, antioxidant activity, reducing power and chelating of ferrous ion in aqueous and alcoholic extracts of Hibiscus sabdariffa L. The total phenolic content was 77.2 mg/g and 87.7 mg/g for the aqueous and alcoholic extracts, respectively. The antioxidant activity was equal in rates for both the roselle alcoholic extract and artificial antioxidant BHT (75.67%), alcoholic extract showed the highest reducing ability with rate 222.60%, the chelating of ferrous ion in both aqueous and alcoholic extracts were 73.97 and 32.29% at 5 mg/ml concentration. The antibacterial activity of roselle extracts against Escherichia coli, Staphylococcus aureus, Streptococcus mutans and Pseudomonas aeruginosa, showed varying degrees of inhibition on the tested organisms.
... It has been reported that roselle extract could inhibit Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus both in ground beef and apple juice (Chao & Yin 2009). Roselle calyces contain antibacterial compounds such as: organic acids, phenolic acids, alkaloids and athocyanins (Christian & Jackson 2009); ascorbic acids and flavonoids (Morales-Cabrera et al. 2013); anthocyanins, flavonoids and polyphenols (Lin et al. 2007). In meat products, roselle calyces could reduce lipid oxidation of kavurma (Bozkurt & Belibagl 2009) and sucuk (Karabacak & Bozkurt 2008). ...
... The color of the roselle calyxes varies from white-yellow to deep red, and it is related to their phytochemical content 4 . Dark calyxes show a greater anthocyanin content, followed by red and pink calyxes, whereas white calyxes show an insignificant or no content of these pigments 5 . Both varieties have in common compounds like organic acids, among which are hydroxycitric and hibiscus acids; flavonoids, such as quercetin, luteolin, hibiscitrin; and phenolic acids; protocatechuic, chlorogenic and malic acids [6][7][8] Red varieties dominate roselle worldwide market, whereas light-red and white varieties are mainly commercialized in local markets. ...
Article
BACKGROUND The calyxes of roselle (Hibiscus sabdariffa) are recognized for their high nutraceutical value, since they decrease body weight and obesity complications, these effects have been attributed mainly to anthocyanins. However, the calyxes comprise important concentration of flavonoids, phenolic and organic acids, which could also contribute to these effects. The objective of this work was to determine the effect of white roselle variety (Alma Blanca) on obesity and hepatic steatosis in high fat‐high fructose diet‐fed rats and compare its beneficial effects with the more studied red variety (Criolla). RESULTS Aqueous and methanolic extracts were prepared from two roselle varieties, Alma Blanca (white) and Criolla (red). The phytochemical profiles were determined using an HPLC‐MS, Criolla extracts contain principally anthocyanins, phenolic acids and flavonoids; anthocyanins were not detected in Alma Blanca. The aqueous extracts of both varieties prevented the body weight gain and decreased adipocytes hyperplasia on rats fed a hypercaloric diet, in addition, these extracts protected against hepatic steatosis. These benefits were associated with hibiscus, dimethyl hibiscus and hydroxycitric acid. CONCLUSION These results demonstrated that calyxes from Hibiscus sabdariffa contain compounds different to anthocyanins with potential benefits to health. The organic acids had the major association with these health benefic effects. This article is protected by copyright. All rights reserved.
... Comparison of total anthocyanin (TA) content showed a significant difference between Vimto calyces (15.5 mg/g) and Koor calyces (6.8 mg/ g). The anthocyanins of H. sabdariffa calyces have already been studied by other authors who reported values from 0.02 mg/g to 25 mg/g Badreldin et al., 2005 ;Christian et al., 2009). These results are rather different from a quantitative standpoint and can be hardly compared to our results as both samples (cultivar is not always specified) and extraction methods were different. ...
Article
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Anthocyanin content of Hibiscus sabdariffa calyces was determined to compare two cultivars from Senegal called Koor and Vimto. Results showed a significant difference in terms of total anthocyanin content (TA) and relative abundance (RA) of anthocyanin species. Values of TA for Vimto were 3-fold higher than Koor’s. Two minor anthocyanins, delphinidine-3-glucoside and cyanidine-3-glucoside, not frequently mentioned in literature, were detected in both cultivars. Cyanidin-3-glucoside in particular was present only in Koor calyces. The influence of agronomic conditions on TA and RA was highlighted.
... (2006) melaporkan bahwa rosella merah (traditional red) dan rosella ungu (early bearing red) memperlihatkan aktivitas antioksidan yang lebih tinggi dibanding rosella putih. Rosella diketahui mempunyai kapasitas sebagai antioksidan terkait komponen antosianin, Ali dkk., 2005;Christian dan Jackson, 2009, Da-Costa-Rocha dkk., 2014. Penelitian Christian dan Jackson (2009) menunjukkan bahwa ekstrak etanol rosella ungu memperlihatkan kadar antosianin yang lebih besar dibanding rosella merah. ...
Article
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Exercise induces more body fluid loss and free radicals formation. Therefore, the body requires an intake of isotonic drink that rich in antioxidant. Plasma antioxidant has an effect on the human physical fitness. Having high level of anthocyanin and vitamin C, dark red roselle (Hibiscus sabdariffa L) has antioxidant capacity. However, the application of dark red roselle extract as an isotonic drink has not yet been reported. This research was aimed to develop red dark roselle as an isotonic drink with high level of antioxidant and ability to increase human physical fitness in exercise. This study was conducted in two stages. The first stage was extraction of dark red roselle with different solvent. The extract with highest antiradical activity was used for isotonic drink formulation. In the second stage, the antioxidant capacity and its effectiveness on improving physical fitness in exercise were evaluated on the isotonic drink with the highest level of consumer preference. The result showed that extraction technique using distilled water gave an extract with the highest antiradical activity. The isotonic drink containing 50% dark red roselle extract showed the highest consumer preference level. The drink showed to have potentially antiradical and capability for increasing physical fitness in exercise with the score of PFI (physical fitness index) reached 52.3 indicating a medium level of physical fitness. ABSTRAK Olahraga menginduksi kehilangan cairan tubuh dan pembentukan radikal bebas yang lebih banyak. Oleh karena itu, tubuh membutuhkan asupan minuman isotonik yang kaya antioksidan. Antioksidan plasma berpengaruh pada kebugaran tubuh manusia. Rosella ungu (Hibiscus sabdariffa L) memiliki kapasitas sebagai antioksidan karena memiliki kadar antosianin dan vitamin C yang tinggi. Aplikasi ekstrak rosella ungu sebagai minuman isotonik belum pernah dilakukan sebelumnya. Penelitian ini bertujuan untuk mengembangkan rosella ungu sebagai minuman isotonik yang berpotensi antioksidan dan mampu meningkatkan kebugaran tubuh pasca stress fisik. Penelitian ini dilakukan dalam beberapa tahap. Ekstraksi rosella ungu menggunakan pelarut yang berbeda dilakukan pada tahap pertama. Ekstrak dengan aktivitas antiradikal tertinggi digunakan untuk formulasi minuman isotonik. Pada tahap terakhir, minuman isotonik dengan tingkat kesukaan konsumen tertinggi dievaluasi kapasitas antioksidan dan efektivitasnya dalam peningkatan kebugaran tubuh pasca stress fisik. Hasil penelitian menunjukkan bahwa teknik ekstraksi menggunakan air sebagai pelarut menghasilkan ekstrak dengan aktivitas antiradikal tertinggi, yaitu mencapai ekuivalen 93,16 ± 3,94 mmol BHT/L. Minuman isotonik dengan penggunaan 50% ekstrak rosella ungu menunjukkan tingkat kesukaan konsumen tertinggi. Minuman isotonik rosella ungu terbukti berpotensi sebagai antiradikal dan mampu meningkatkan kebugaran tubuh pasca stress fisik dengan skor IKJ (indeks kesegaran jasmani) mencapai 52,3 yang mengindikasikan tingkat kebugaran sedang.
... It is also rich in bioactive compounds such as anthocyanins and other flavonoids, organic acids and polysaccharides which are responsible for its antioxidant, antibacterial, anti-inflammatory, hepatoprotective and anticholesterol activities (Da-Costa-Rocha et al., 2014;Formagio et al., 2015). The composition of H. sabdariffa in terms of phenolic compounds has been previously analysed by some authors (Borrás-Linares et al., 2015;Christian & Jackson, 2009). Moreover, Borrás-Linares et al. (2015), chemically characterized the H. sabdariffa ethanolic extract, reporting the presence of a great variety of phenolic compounds and organic acids, such as citric acid, hibiscus acid, hydroxycitric acid and protocatechuic acid, being the main phenolic acid present the latest mentioned compound, otherwise, quercetin glycosides and gossypetin were the major flavonoids found. ...
Article
The nutritional and bioactive composition of plants have aroused much interest not only among scientists, but also in people's daily lives. Apart from the health benefits, plants are a source of pigments that can be used as natural food colorants. In this work, the nutritional composition of Hibiscus sabdariffa L. was analysed, as well as its bioactive compounds and natural pigments. Glucose (sugar), malic acid (organic acid), α-tocopherol (tocopherol) and linoleic acid (fatty acid) were the major constituents in the corresponding classes. 5-(Hydroxymethyl) furfural was the most abundant non-anthocyanin compound, while delphinidin-3-O-sambubioside was the major anthocyanin both in its hydroethanolic extract and infusion. H. sabdariffa extracts showed antioxidant and antimicrobial activities, highlighting that the hydroethanol extract presents not only lipid peroxidation inhibition capacity, but also bactericidal/fungicidal inhibition ability for all the bacteria and fungi tested. Furthermore, both extracts revealed the absence of toxicity using porcine primary liver cells. The studied plant species was thus not only interesting for nutritional purposes but also for bioactive and colouring applications in food, cosmetic and pharmaceutical industries.
... It is also rich in bioactive compounds such as anthocyanins and other flavonoids, or- ganic acids and polysaccharides which are responsible for its anti- oxidant, antibacterial, anti-inflammatory, hepatoprotective and antic- holesterol activities (Da-Costa-Rocha et al., 2014;Formagio et al., 2015). The composition of H. sabdariffa in terms of phenolic com- pounds has been previously analysed by some authors (Borrás-Linares et al., 2015;Christian & Jackson, 2009). Moreover, Borrás- Linares et al. (2015), chemically characterized the H. sabdariffa ethanolic extract, reporting the presence of a great variety of phenolic compounds and organic acids, such as citric acid, hibiscus acid, hydroxycitric acid and protocatechuic acid, being the main phenolic acid present the latest mentioned compound, otherwise, quercetin glycosides and gossypetin were the major flavonoids found. ...
Article
Herbs have been used from ancient times for infusion preparation based on their potential health effects. In particular, the consumption of Hibiscus sabdariffa L., Crataegus spp. and Panax spp. has been largely associated to cardiovascular benefits. In this work, the label information of 52 herbal products for infusion preparation containing the referred herbs was analyzed and discussed, taking into consideration the European Union regulation for herbal products, which intends to protect public health and harmonize the legal framework in Member States. Details about the cardiovascular-related statements and warning notifications about consumption were considered. Also, regulatory issues and possible herb-drug interactions were explored and discussed. A total of 14 of the 52 herbal products selected presented health claims/statements on the label. Hibiscus was present in the majority of the products and, in some cases, it was mentioned only in the ingredients list and not on the product front-of-pack. Despite the promising outcomes of these plants to modulate cardiovascular risk markers, consumers with some sort of cardiovascular dysfunction and/or under medication treatments should be aware to carefully analyze the labels and consult additional information related to these herbal products. Manufacturers have also a huge responsibility to inform consumers by presenting awareness statements. Lastly, health professionals must advise and alert their patients about possible interactions that could occur between the concomitant consumption of drugs and herbs. Overall, there is still a real need of additional studies and clinical trials to better understand herbs effects and establish a science-based guidance to assess their safety.
... Antioxidants assist in preventing cell damage by limiting the formation of free radicals, acting as free radical scavengers and promoting their decomposition (16). Hibiscus sabdariffa and Citrus sinensis have gained attention for their antioxidant activity (17)(18)(19). Sorrel and citrus by-product extracts possessed similar antioxidant activities (141.57 µmol/g ± 5.27 and 139.77 ...
... Consequently, these assays are vital for identifying inhibitors with potential to reduce the postprandial glycemic response. 25 The three varieties of H. sabdarif fa extracts exhibited negligible or no inhibition of human α-amylase activity. The highest inhibition value obtained was only 8% with the dark red variety even at 6 mg/mL. ...
Article
Three varieties of Hibiscus sabdariffa were analyzed for their phytochemical content and inhibitory potential on carbohydrate-digesting enzymes as a basis for selecting a variety for wine production. The dark red variety was chosen as it was highest in phenolic content and partially inhibited α-glucosidase (maltase), with delphinidin 3-O-sambubioside, cyanidin 3-O-sambubioside and 3-O-caffeoylquinic acid accounting for 65 % of this activity. None of the varieties significantly inhibited α-amylase. Regarding Hibiscus sabdarifa wine, the effect of fermentation temperature (20 and 30 ˚C) on the physicochemical, phytochemical and aroma composition was monitored over 40 days. The main change in phytochemical composition observed was the hydrolysis of 3-O-caffeolquinic acid and the concomitant increase of caffeic acid irrespective of fermentation temperature. Wine fermented at 20 ˚C was slightly more active for α-glucosidase inhibition with more fruity aromas (ethyl octanoate), but there were more flowery notes (2-phenylethanol) at 30 ˚C.
... Several researchers have pointed out that Roselle extracts may have various therapeutic effects; one of them is the antioxidant capacity, attributed mainly to the content of anthocyanins and phenolic compounds (Tsai, Mcintoshb, Pearceb, Camdenb, & Jordanc, 2002;Tsai & Huang, 2004; Anokwuru, Esiaba, Ajibaye, & Adesuyi, 2011; Amer, El-Sharkawy, Abdel Bar, & Ashour, 2012). It has been reported higher antioxidant capacity in Roselle calyces of red variety than in the white one variety (Christian & Jackson, 2009). ...
Article
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The effect of average particle sizes (APS: 0.45 and 1.01 mm), solvent types (ST: distilled water, 2% citric acid solution, and 50% ethanol), and extraction times (ET: 40, 50, and 60 min) on the physicochemical properties, antioxidant capacity, and half maximal effective concentration (EC50) in calyces of Roselle (Hibiscus sabdariffa) was analyzed. The extracts obtained with distilled water and 2% citric acid solution had an intense red color which purities (C) were 78.5 ± 2.3 and 79.8 ± 2.2, respectively. The alcoholic extracts showed a dark red color (C = 75.9 ± 1.8). The alcoholic (820.2 ± 73.7 mg Trolox equivalents (TE)/100 g dry calyces) and acid extracts (773.34 ± 53.0 mg TE/100 g dry calyces) showed higher antioxidant capacity than the aqueous extracts (673.24 ± 116.0 mg TE/100 g dry calyces). The EC50 value was better for the alcoholic extracts, followed by the 2% citric acid extracts and finally by the aqueous extracts (13.4 ± 1.0, 14.9 ± 1.0, and 17.2 ± 1.2 mg of extract, respectively). According to results, the best antioxidant properties were achieved using an APS of 0.45 mm, 50:50% ethanol:water ratio, and ETs of 30 or 45 min.
... The analyses performed were color measurement using chromameter (Konica Minolta CR-400) (Madeira et al. 2003;Duangmal et al. 2008), deter mination of pH using pH meter (AOAC, 2005), total soluble solid using hand refractometer (ATAGO) (Nielsen, 2010), extraction yield using rotary vacuum evaporator (Buchi R-210) (Zhang et al. 2007), total anthocyanin content using pH differential method (Christian and Jackson, 2009), total phenolic content using Folin-Ciocalteu method (Slinkard and Singleton, 1977), antioxidant activity analysis using DPPH method (Amin and Lee, 2005). ...
Article
This research was carried out to develop a functional ice cream product with natural colorant derived from an optimum set of roselle calyces extract and citric acid concentrations. Although citric acid can improve red color stability of rosella, its addition is limited due to the acidic and bitter aftertaste it imparts. Response surface methodology (RSM) was employed to analyze the effect of roselle calyces extract and citric acid on physico-chemical characteristics and sensory acceptance of an ice cream. A central composite design consisting of two independent variables (roselle calyces extract and citric acid cocentrations) at five levels (-1.41421, -1, 0, +1, and +1.41421) with 13 runs (formulations) was prepared to establish the optimum set of variables. Higher concentration of roselle calyces extract significantly increased the total anthocyanin content and color acceptance, while decreased the ºHue and pH of the ice cream. Higher concentration of citric acid significantly increased the overrun and color acceptance, but decreased the viscosity, ºHue, pH, texture, taste acceptance, and overall acceptance of ice cream. The optimum scores of consumer sensory acceptance were met at 11.5% roselle calyces extract and 1.5% citric acid concentrations.
... Anthocyanin, as an important part of phenolic compound, attracts much attention due to its antioxidant effects and health benefits (Khoo et al., 2017). Besides, anthocyanin content can help to assess quality, maturity stage, and also in determining the harvesting time of a plant (Christian and Jackson, 2009). The conventional destructive biochemical analysis of anthocyanin is discontinuous, time-consuming, and costly since it involves harvesting, multiple extraction steps before reaching the quantification stage (Nakata and Ohme-Takagi, 2014). ...
Article
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Fluorescence imaging has shown great potential in non-invasive plant monitoring and analysis. However, current systems have several limitations, such as bulky size, high cost, contact measurement, and lack of multifunctionality, which may hinder its applications in a wide range of settings including indoor vertical farming. Herein, we developed a compact handheld fluorescence imager enabling multipurpose plant phenotyping, such as continuous photosynthetic activity monitoring and non-destructive anthocyanin quantification. The compact imager comprises of pulse-amplitude-modulated multi-color light emitting diodes (LEDs), optimized light illumination and collection, dedicated driver circuit board, miniaturized charge-coupled device camera, and associated image analytics. Experiments conducted in drought stressed lettuce proved that the novel imager could quantitatively evaluate the plant stress by the non-invasive measurement of photosynthetic activity efficiency. Moreover, a non-invasive and fast quantification of anthocyanins in green and red Batavia lettuce leaves had excellent correlation (>84%) with conventional destructive biochemical analysis. Preliminary experimental results emphasize the high throughput monitoring capability and multifunctionality of our novel handheld fluorescence imager, indicating its tremendous potential in modern agriculture.
... In this study, the Pearson correlation also showed that there was no correlation between total anthocyanins and total phenolics with antioxidant activity of UKMR-2 calyx in both CO2 treatments. No correlation between antioxidant activity levels with TPC and TAC showed that there were other components besides phenolic compounds in calyx such as ascorbic acid and strong water-soluble antioxidants which were likely to contribute to its antioxidant activity [38,39]. These findings were the same as Mohd-Esa et al.'s findings [40], which indicated no correlation between TPC and antioxidant activity in roselle water extract from Terengganu. ...
Article
The impact of global climate change on plants which has been widely reported can exhibit significant changes on the growth, yield and metabolite production. Studies on the impact of elevated carbon dioxide concentration, [CO2] on plant growth and production of phenolic constituents in Hibiscus sabdariffa var. UKMR-2 has not been reported in any previous studies. This study investigated the growth quality and production of phenolic constituents of UKMR-2 under different [CO2]. The cultivation was subjected to two atmospheric [CO2]; ambient (400 µmol/mol), and elevated (800 µmol/mol). Selected parameters for growth performance were recorded throughout the plant development. UKMR-2 calyx extract was analysed for total phenolic, total anthocyanins, antioxidant activity, and evaluated based on HPLC-PDA method. The results revealed that UKMR-2 responded differently to the [CO2] treatments. The results clearly showed that exposure to elevated [CO2] increased calyx yields, production of phenolic constituents, and antioxidant activity. Furthermore, different [CO2] had significant interaction on the production of phenolic constituents, and antioxidant activity (p < 0.05), except for plant growth. The HPLC-PDA showed the presence of delphinidin-3-O-sambubioside, cyanidin-3-O-sambubioside, ascorbic acid, caffeic acid, and chlorogenic acid. Therefore, increased [CO2] may have significant effects on UKMR-2 to not only produce higher production yields, but also on the production of phenolic constituents with potential physiological impact to human health.
... Penelitian lain menyatakan bahwa semakin pekat warna merah pada rosela menunjukkan kandungan antosianin yang semakin tinggi. Hasil yang serupa ditemukan oleh Tahir tahun 2017 yang membandingkan tiga jenis varietas rosela menunjukkan rosela dengan warna kelopak merah pekat memiliki kandungan antosianin paling tinggi dibanding dua varietas lainnya (rosela merah dan putih) 23 . Sementara itu, pemanfaatan rosela dalam bentuk crude (bubuk) tidak memberikan efek perbaikan pada biomarker stress oksidatif disebabkan karena konsentrasi polifenol yang rendah dibandingkan dalam bentuk ekstrak bubuk 24 . ...
Article
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Background : Rosela (Hibiscus sabdariffa L.) is an anthocyanin-rich plant that has good antioxidant capacity. However, the utilization was limited to red roselle, while previous studies showed that anthocyanin content was found to be higher in the thick roselle.therefore, this is an opportunity to develop purple roselle products as a preventive effort for degenerative diseases in men with fatness. Subjects in this study were male by considering the effect of estrogen on women which could play a role in suppressing oxidative stress. Objectives : This study aimed to analyze antioxidant (SOD/Superoxide dismutase) and oxidative status (MDA/malondialdehyde) level in obese adult men after administration of purple rosela drinks. Methods : This study was quasi-experimental with pre-post test. Eighteen obese subjects in the security unit were divided into two groups, namely the intervention group and control group. Intervention group (n = 9) was given purple rosela drinkin the amount of 480 mL/day, while the control group (n = 9) was given an equivalent amount of purple rosela drink without rosela. The subjects were daily administered for 6 weeks. Characteristic, anthropometric, food consumption and blood sample data were collected at the beginning and end of the intervention. Data analysis was performed by descriptively, paired t-test, independent t-test, ANCOVA. Results : The analysis showed that purple rosela drink tend to increase SOD levels (0.45 ± 0.14; 1.35 ± 0.71; p-value = 0.008) but this value was not significantly different from the control group (p-value = 0.128). MDA levels did not significantly different between the intervention and control groups (0.025 ± 0.083;-0.125 ± 0.60; p-value = 0.473). Conclusion : These results showed that administering 480 ml of purple rosela drink did not improve antioxidant and oxidative status in obese adult men.
... The high number of anthocyanins, phenolic and antioxidants in the HS flowers play a unique role in the color of this plant which can be categorized into three different varieties designated traditional, white, dark and light red. Several studies presented a comparison of these three varieties, the dark red hibiscus sabdariffa (R 2 HS) displayed a superior percent of anthocyanins, phenolic, and antioxidant than the light red hibiscus sabdariffa (R 1 HS) while the white hibiscus sabdariffa (WHS) lacks anthocyanins [37][38][39] . The anthocyanin in the dark and light red HS is composed of cyanidin-3-glucoside, delphinidin-3-glucoside, cyanidin-3-sambubioside, and delphinidin-3-sambubioside [40][41][42] . ...
Article
For future development of environmentally friendly and sustainable electrode materials, novel orthorhombic vanadium pentoxide@carbon composites (V2O5@C-WHS, V2O5@C-R1HS and V2O5@C-R2HS) were synthesized using a green solvothermal process. From the SEM and TEM analysis, vanadium pentoxide@carbon (V2O5@C) composites materials shown flower-like morphologies with the smallest agglomerated nanoflakes on the surface. The incorporation of carbon into the V2O5 matrix was established from the element distribution mapping images, Raman, FTIR and XPS methods. The V2O5@C-R2HS composite presented the smallest thickness (40 nm) of the flower-like morphology and the highest amount of carbon and V5+ ions. The electrochemical performance of all the electrodes materials was studied in three-electrode configurations using 6 M KOH aqueous electrolyte. The V2O5@C-R2HS composite electrode displayed a better electrochemical performance than V2O5@C-WHS and V2O5@C-R1HS composites. A two-electrode configuration was evaluated using the V2O5@C-R2HS composite as a positive electrode and an activated carbon as a negative electrode to fabricate an asymmetric device (V2O5@C-R2HS//AC). The V2O5@C-R2HS//AC device presented a specific energy and an associated specific power of 33.4 W h kg-1 and 670 W kg-1, respectively at 1 A g-1 in a voltage of 1.6 V. The asymmetric cell showed excellent cycling stability of 98.9% coulombic efficiency and 88% capacity retention up to a large number of the cycles (25.000). This study confirmed that this novel green V2O5@C-R2HS composite can ensure far better performance as a positive electrode for future sustainable supercapacitors.
... Hibiscus is a source of bioactive compounds such as polyphenols, carotenoids, ascorbic acid, and tannins; however, the composition varies depending on the part of the plant used, climatic factors, maturity of the plant, and differences in genotypes. 18 The calyces of hibiscus are a rich source of anthocyanins, mainly delphinidin 3-sambubioside and cyanidin 3-sambubioside, with delphinidin 3-glucoside and cyanidin 3-glucoside reported as minor anthocyanins. 19 It is thought that the bioactive compounds in hibiscus exert antioxidant and anti-inflammatory effects that contribute to the reduction of CVD risk markers. ...
Article
Context: Hibiscus sabdariffa (hibiscus) has been proposed to affect cardiovascular risk factors. Objective: To review the evidence for the effectiveness of hibiscus in modulating cardiovascular disease risk markers, compared with pharmacologic, nutritional, or placebo treatments. Data sources: A systematic search of the Web of Science, Cochrane, Ovid (MEDLINE, Embase, AMED), and Scopus databases identified reports published up to June 2021 on randomized controlled trials using hibiscus as an intervention for lipid profiles, blood pressure (BP), and fasting plasma glucose levels in adult populations. Data extraction: Seventeen chronic trials were included. Quantitative data were examined using a random effects meta-analysis and meta-regression with trial sequential analysis to account for type I and type II errors. Data analysis: Hibiscus exerted stronger effects on systolic BP (-7.10 mmHg [95%CI, -13.00, -1.20]; I2 = 95%; P = 0.02) than placebo, with the magnitude of reduction greatest in those with elevated BP at baseline. Hibiscus induced reductions to BP similar to that resulting from medication (systolic BP reduction, 2.13 mmHg [95%CI, -2.81, 7.06], I2 = 91%, P = 0.40; diastolic BP reduction, 1.10 mmHg [95%CI, -1.55, 3.74], I2 = 91%, P = 0.42). Hibiscus also significantly lowered levels of low-density lipoprotein compared with other teas and placebo (-6.76 mg/dL [95%CI, -13.45, -0.07]; I2 = 64%; P = 0.05). Conclusions: Regular consumption of hibiscus could confer reduced cardiovascular disease risk. More studies are warranted to establish an effective dose response and treatment duration. Systematic review registration: PROSPERO registration no. CRD42020167295.
... As for all vegetal materials, phenolic content may be affected by several agronomic factors, and the best conditions for producing polyphenol-rich roselle plants are still to be established. Thus when total polyphenol content and anthocyanin content were evaluated in three roselle varieties at different moments of maturity (preflowering stage and days 3, 7, 21, and 35 after flowering), different tendencies were observed for each variety (Christian & Jackson, 2009). Another study showed that the use of poultry litter as organic fertilizer did not modify the phenolic compound content of roselle, thus constituting a potential use through which to valorize this residue (Formagio et al., 2015). ...
Book
Roselle: Production, Processing, Products and Biocomposites complies the latest findings on the production, processing, products and composites of the roselle plant. The book provides researchers with the latest information on its entire use, including fibers and fruit for any application. Subjects covered include environmental advantages and challenges, the plant as a renewable resource, economic issues such as the impact of biobased medicines, biodiesel, the current market for roselle products and regulations for food packaging materials. Sections include commentary from leading industrial and academic experts in the field who present cutting-edge research on roselle fiber for a variety of industries. By comprehensively covering the development and characterization of roselle fiber as a potential to replace conventional fiber made from petroleum-based polymers, this book is a must-have resource for anyone requiring up-to-date knowledge on the lifecycle of the roselle plant.
... Coffie [11] reported significant variations in the morphological characteristics among 35 genotypes of roselle across West Africa. Likewise, the antioxidant activity has been reported to be influenced by different varieties as well as maturity stages of roselle [10]. ...
Article
Roselle (Hibiscus sabdariffa L.) is recognized as a valuable food crop due to its nutraceutical potential, rich pigment content, and medicinal properties. However, there is limited information on planting dates and suitable genotypes for roselle cultivation in arid and semi-arid regions. The objective of this field study was to investigate the influence of five planting dates (March, April, May, June, and July) on morphological and phytochemical characteristics of different roselle genotypes. Among genotypes, eight (Jiroft, Dalgan, Bampoor, Iranshahr, Nikshahr, Roodbar, Saravan, and Qaleganj) were Iranian landraces, and HA and HS-24 were originated from Ghana and Bangladesh, respectively. Planting date significantly influenced the number of branches, bolls and seeds per plant, sepal fresh weight, calyx and biomass yields, and harvest index in tested roselle landraces. The greatest morphological growth, fresh sepal weight (50.6 g plant−1) and calyx yield (1519 kg ha−1) were observed with the roselle planted in early May. Moreover, amounts of chlorophyll, flavonoids and antioxidant remained higher in roselle when planted between April–May. The number of branches/plant was found to be an important determinant of calyx yield (r = 0.707) in roselle. Dalgan resulted in the greatest growth and yields within a comparatively shorter period of time compared to other tested landraces. Both principal component analysis (PCA) and cluster analysis also indicated that Dalgan landrace possessed most suitable morphological and phytochemical traits among tested landraces, and therefore, it could be planted adopted for extensive cultivation settings in the arid and semi-arid regions.
... This is because the content of vitamin C and the total phenols in the nanocapsules made from Arabic gum was greater than nanocapsules that used maltodextrin. Christian and Jackson (2009) stated that the role of antioxidant activity in rosella was not only by anthocyanins as a phenolic group but also the content of vitamin C. The higher levels of anthocyanin in effervescent tablets, the higher antioxidant activity. In this study, effervescent tablets which have formulas with high vitamin C and anthocyanin content will also have a high antioxidant capacity, namely in formulas using Arabic gum with a value of 34.02%. ...
Article
Roselle flowers are usually consumed in the form of fresh steeping. To increase the flexibility of using roselle, effervescent roselle-based products are made which of course more practical, efficient and attractive. Unfortunately, the bioactive compound in roselle extracts is not stable to environmental influences so nanoencapsulation technology needs to be done. The encapsulation matrix type gives a unique effect on each core. The purposes of this study were to determine the effects of variation in the matrix types and percentage of roselle nanocapsules on the physical and chemical effervescent properties. The research design used in this study was a Complete Random Design with 2 factors and 3 replications. The first factor comprised matrix types (A): maltodextrin (A1) and Arabic gum (A2). The second factor was roselle nanocapsule percentages (B): 10% (B1), 15% (B2) and 20% (B3). Observed variables in this study were total phenol, anthocyanin, vitamin C, antioxidant activity and dissolving time. The Arabic gum nano encapsulated matrix type gave a better value of Vitamin C, antioxidant activity and dissolving time than maltodextrin, namely 0.149±0.049 µg/3 g, 34.02±4.52%, 2.93±0.80 mins. The percentage of roselle nanocapsules by 20% gave the highest vitamin C value, namely 0.188±0.032 µg /3 g. The best treatment combination was obtained from the treatment (A2B3) Arabic gum nanocapsules using the third percentage (20%) with the characteristics: total phenol content 4.17 µg /3 g, anthocyanin 0.070 µg /3 g, vitamin C 0.188 µg /3 g when it dissolves in 1.25 mins.
... The total phenolic compounds in the darker colored (red) roselle were roughly three times higher than the lighter one (pink). This result was in accordance with the former study [36], which showed that darker colored roselle contained much higher total phenolic compounds compared to the lighter colored and white roselle in the early stage of maturity. * tentative amount due to the concentration less than LOQ but higher than LOD. ...
Article
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Phenolics are bioactive compounds already reported in Hibiscus sabdariffa (roselle). The present study reports the development and validation of the analytical microwave-assisted extraction (MAE) method for the determination of phenolic compounds in roselle flowers to establish their positive contribution to human health. Prior to the optimization, a study for identifying phenolic compounds revealed that chlorogenic acid, protocatechuic acid, caffeic acid, and rutin were presented in Roselle. Three factors affecting MAE, viz. temperature, solvent composition, and sample to solvent ratio, were optimized employing a Box-Behnken Design (BBD) in conjunction with response surface methodology (RSM). The maximum extraction recovery was achieved using the extraction temperature of 68 °C, solvent composition of 59% MeOH in water, and 20:1 solvent to sample ratio. The kinetics experiment confirmed full recoveries (92–119%) at 15 min. Subsequently, method validation showed a satisfactory result, including low detection limits from 0.219 mg L−1 (caffeic acid) to 0.374 mg L−1 (chlorogenic acid). Both precisions and accuracy met the acceptances by AOAC. Finally, the method was successfully applied to quantify phenolics in the two most common varieties of Roselle. Chlorogenic acid was found as the main phenolic compound in both varieties
... The addition of HM increased the antioxidant activity and total phenolic content in all yogurt samples (p \ 0.01). Various studies have reported that the antioxidant activity and phenolic content of Hibiscus sabdariffa L. are very high (Christian and Jackson 2009;Riaz and Chopra 2018). Mohd-Esa et al. (2010), have reported that, the total phenolic contents of the Hibiscus sabdariffa L. seeds, leaves, flower and stem tissues of in the methanol extract were were 4.87, 2.91, 2.20 and 1.31 mg GAE/g, respectively, and the total antioxidant activity values were 78.7, 61.5, 54.9 and 22.1%, respectively. ...
Article
Full-text available
In this study, the effect of Hibiscus sabdariffa L. flowers marmalade (HM) addition at different ratios (0%, 15%, 20%) was determined on the certain quality properties, total phenolic contents, antioxidant activity, mineral composition and heavy metal content of stirred-type yogurts (C, HM15, and HM20). The marmalade addition increased dry matter, ash, titratable acidity and viscosity whereas decreased pH, fat and protein values. HM addition significantly increased the antioxidant properties of yogurt samples. 2,2-Diphenylpicrylhydrazyl radical-scavenging activity, Copper (II) reducing antioxidant capacity and total phenolic content were found to be in the range of 5.92–26.73 mg TE/100 g, 4.88–15.03 mg TE/100 g, and 5.57–14.69 mg GAE/100 g, respectively. There were no statistically differences between control and HM-added groups in terms of lactic acid bacteria (LAB) counts, also in all samples the total LAB count was above 6 Log cfu/g during the storage. Fe, Mn, B, and Ba mineral values of samples with HM were higher than control sample. Cd, As, Hg and Li heavy metals were not detected in any of the samples, consequently results were within reliable limits reported by JECFA (Joint FAO/WHO Expert Committee on Food Additives) and Turkish Food Codex. As a result of the sensory evaluation, the samples containing 20% HM generally received higher scores than the samples containing 15% HM. Considering all the parameters, it was concluded that HM yogurts can be used as a different type in the functional yogurt industry due to its pleasant and characteristic taste.
... altissima Wester ve ikincisi Hibiscus sabdariffa var. sabdariffa'dır (Christian and Jackson, 2009). ...
... In addition, available medical literatures show that various extract of this plant reduces cholesterol [4], lipid [5], blood viscosity [6] and blood pressure [7]. Furthermore, this plant have also been known to have anti-hypertensive [8], antidiabetic [9], antioxidant [10,11] antipyretic, anticancer, antiseptic [12] and hepatoprotective [13] activities. The main compounds found in calyx of Hibiscus sabdariffa are citric acid, malic acids, anthocyanins, flavonoids, glycosides [14] caffeic acid, polyphenolic acid, protocatechuic acid, catechin and gallocatechins [15]. ...
Article
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Background/Objective: Methanolic extract of Hibiscus sabdariffa extract usually produces a brilliant reddish liquid and it is believed that modification of this colored liquid may have good staining effect on thin blood smear. Therefore, this study aims to examine the staining effect of modified methanolic extract of Hibiscus sabdariffa calyx on thin peripheral blood smear in other to obtain surrogates hematological stains. Materials and methods: Dried calyx of Hibiscus sabdariffa was obtained commercially from Yola. The calyces were pulverized to fine powder and 10g of the powder was soaked in 50ml of absolute methanol for 12hours to obtain methanolic extract and thereafter, equal volume of both methanolic extract and methylene blue were mixed to obtain a modified methanolic extract. pH of modified extract was determined using pH meter. The modified methanolic extract was further used to stain thin peripheral blood smear. Results: Modified methanolic extract of Hibiscus sabdariffa calyx had pH of 7.1. The extract produces a poor staining effect on erythrocyte but gave a deep blue coloration on leucocytes, while the control stains such as field stain and Leishman stain produces a normal coloration on leucocytes and a dark pink coloration with normal pallor on erythrocyte. Conclusion: Modified methanolic extract of Hibiscus sabdariffa calyx has PH of 7.1 and produces a poor staining effect on erythrocyte but impacted a deep blue coloration on nuclear lobes of leucocytes microscopically. More research to get a modified concentration and a molar equilibrium of acidic and basic components in this extract is recommended.
... As expected, R1 (white samples) had the lowest values for color density than other samples; this was reflected in the absence of TAC in white Hs samples. Similar results were reported in the literature (Christian & Jackson, 2009;Tahir et al., 2017). TAC in red Hs samples was varied significantly between minimum in R9 (30.46 ± 0.61) and maximum in R4 (107.70 ± 0.030). ...
... Roselle calyces have phenolic compounds, especially anthocyanins [17,18]. Three roselle varieties exhibited antioxidant activity, inhibiting lipid peroxidation between 69 and 79% [19]. The antibacterial activity of roselle extracts against Escherichia coli, Staphylococcus aureus, Streptococcus mutans and Pseudomonas aeruginosa, showed varying degrees of inhibition on the tested organisms [3] . ...
Article
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Increasing concerns on the adverse effect of synthetic antioxidants and the emergence of antibiotic-resistant Staphylococcus aureus have become two essential problems to be addressed. To tackle them, exploration of natural resources to discover novel antioxidants and/or antibacterial agents is urgently required. The aim of this research was to investigate the correlation of phenolic and flavonoid contents of extracts to their antioxidant and antibacterial activities. Green tea, green coffee, cocoa pod husks, bee pollen, and rosella calyces were processed and subjected to 80% ethanol-based maceration procedure to obtain extracts with appropriate condition. Each extract was examined for its phenolic and flavonoid concentrations using the Folin–Ciocalteau method and the aluminum chloride colorimetric assay, respectively. Further analysis on the free-radical scavenging potential and antibacterial/antibiofilm activity against S. aureus were carried out. Samples were found to contain total phenolics (TP) and total flavonoids (TF) at different concentrations. The highest level of TP and TF was identified in green tea extract and corresponded to the lowest IC 50 against DPPH and the lowest MIC against S. aureus colonies or to their respective biofilm. In contrast, low amounts of TP and TF were found in cocoa pod husks and bee pollen which were further demonstrated high IC 50 and high MIC. Collectively, our results suggested the linear correlation of phenolic- and flavonoid contents to the antioxidant and antibacterial/antibiofilm activities of plant extracts. The higher the phenolics and flavonoids level, the better the antioxidant and antibacterial/antibiofilm activities obtained from the corresponding extracts.
... Los investigadores concluyen que, en el mercado costarricense, el perfil en compuestos fenólicos de las tisanas varía de acuerdo con el productor, por lo que el consumidor que busca algún efecto beneficioso para su salud a través del consumo de bebidas de rosa de Jamaica obtendrá resultados diferentes de acuerdo con la marca del producto que consuma [14]. Los resultados también coinciden con lo encontrado por varios autores que destacan la presencia de fenoles totales en mayor concentración en aquellos extractos de cálices comerciales y colores diversos [15][16][17]. En lo que respecta a la cuantificación de los flavonoides presentes en los extractos, se evidenció una diferencia significativa (p<0,05) (ver tabla 2). Los flavonoides constituyen el grupo de compuestos fenólicos más diverso y ampliamente distribuido en las plantas. ...
Article
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Resumen El fácil acceso y preparación de bebidas a base de Hibiscus sabdariffa L. representa una alternativa en el tratamiento de enfermedades crónicas y degenerativas. El estudio tuvo como objetivo comparar la contracción de fenoles totales y flavonoides en cálices de Hibiscus sabdariffa L., de una marca comercial y otra sin permiso sanitario. Para la determinación de fenoles totales se utilizó el método de Folin-Ciocalteu y método colorimétrico de Marinova para flavonoides. Se encontró una diferencia estadísticamente significativa (p<0,05) en la concentración de fenoles totales y flavo-noides. Estos resultados demuestran que existen factores que condicionan el conte-nido de compuestos fenólicos, flavonoides y otros compuestos bioactivos. Palabras clave: Hibiscus sabdariffa L., polifenoles, flavonoides. Summary Comparison of total phenolic compounds in Hibiscus sabdariffa L. Venezuela The easy access and preparation of drinks based on Hibiscus sabdariffa L. represents an alternative in the treatment of chronic and degenerative diseases. The objective of the study was to compare the contraction of total phenols and flavonoids in chalices of Hibiscus sabdariffa L., of one commercial brand and another without sanitary Artículo de investigación científica / http://dx.doi.org/10.15446/rcciquifa. v48n3.84956
... Quercetin, myricetin and proanthocyanidins, of the epigallocatechin and epigallocatechin-gallate type catechin, are flavonoids found in H. sabdariffa [43]. Anthocyanin (delphinidin 3-O-sambubioside and cyanidin 3-O-sambubioside) are one of the flavonoids with the greatest presence and activity [44], giving several interesting properties in H. sabdariffa: An increase in anthocyanin content causes an increase in activity against free radicals; this metabolite contributes 51% of the Roselle antioxidant capacity [45]; they may potentially prevent diseases; give the color of the calyces" dark calyces have more anthocyanin than light calyces, but whites or greens lack these flavonoids [46], reason why this compound have been studied extensively [47]. Although white Roselle calyces had no anthocyanin and tannin content, the antioxidant activity of its extract could be due to the presence of phenolic acids and other polyphenols [34]. ...
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... Typically, the obtained crude extracts will contain a mixture of different phenolic acids as well as other compounds (e.g., flavonoids, pigments) [101,116,265]. If necessary, the crude extracts can be further fractionated or purified by means of preparative chromatographic techniques (i.e., preparative high pressure liquid chromatography (HPLC), thin-layer, flash, or counter-current chromatography (CCC)) or other techniques such as liquid-liquid extraction (LLE) and solid phase (SPE) extraction [266]. ...
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Biotechnological production of phenolic acids is attracting increased interest due to their superior antioxidant activity, as well as other antimicrobial, dietary, and health benefits. As secondary metabolites, primarily found in plants and fungi, they are effective free radical scavengers due to the phenolic group available in their structure. Therefore, phenolic acids are widely utilised by pharmaceutical, food, cosmetic, and chemical industries. A demand for phenolic acids is mostly satisfied by utilising chemically synthesised compounds, with only a low quantity obtained from natural sources. As an alternative to chemical synthesis, environmentally friendly bio-based technologies are necessary for development in large-scale production. One of the most promising sustainable technologies is the utilisation of microbial cell factories for biosynthesis of phenolic acids. In this paper, we perform a systematic comparison of the best known natural sources of phenolic acids. The advances and prospects in the development of microbial cell factories for biosynthesis of these bioactive compounds are discussed in more detail. A special consideration is given to the modern production methods and analytics of phenolic acids.
... Data obtained from this study are in agreement with those reported for other Polygonaceae familly species such as English spinach [38] and sorrel [39]. ...
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Chapter
Roselle (Hibiscus sabdariffa) is used as folk medicine and food as well. Being high in anthocyanin, Roselle calyces are both a good colorant and potentially a good source of antioxidants. Bioactive components and antioxidant activity are considered as an important quality index of Roselle. Many attempts have been carried out to establish a highly sensitive and selective analytical tool for quantitative determination of polyphenols. The aim of this chapter is to provide information on the most techniques modern and conventional methods used in the investigation of total polyphenols and antioxidant activities. The concentrations of total phenol content, total flavonoid content, total antioxidant content, ferric reducing antioxidant power, anthocyanins, and 1,1-diphenyl-2-picrylhydrazyl of Roselle can be predicted accurately using near-infrared spectroscopy (NIRS). The overall review suggests that there is a great potential for the field application of NIRS to be used for in situ and nondestructive determination of bioactive components and antioxidant activity in Roselle.
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This study was carried out on the TP 3 in 1TM juice formulation, which consisted of pomegranate concentrate with guava and roselle extract. This study aimed to determine its physicochemical properties, proximate content, total phenolic content, antioxidant activity, total sugar, vitamin C and several targeted polyphenol compounds. Total phenol content was determined using Folin-Ciocalteu method while antioxidant activity was determined using DPPH and ABTS methods. The results showed pH and total soluble solid values of the juice were 3.69 and 8.1 °Brix, respectively. The juice has brightness colour of L = 33.25, a = 3.16 and b = -4.63. Every 100 ml juice contained 10.92 g total sugar, 4 mg vitamin C and 0.44% titratable citric acid. Proximate analyses showed TP 3 in 1TM juice contained 89.38% moisture, 0.15% total ash, 0.16% protein, 0% fat and 10.31% total carbohydrates. The juice was low in calories (42 kcal/100 ml) and contained total phenolic (609 mg GAE/100 ml) and total monomeric anthocyanin (12.94 mg C3G/100 ml). Antioxidant value obtained through DPPH and ABTS test methods were 88.90% and 472.44 µM TE/ml, respectively. Eight selected individual polyphenol compounds ranged from 0.13-633.73 mg/100 ml have been identified. TP 3 in 1TM juice consisting three different tropical fruits can be considered of having high phenolic content and antioxidant activity. Consumption of mixed tropical juices with various polyphenol compositions will protect human body from several diseases attributed to the reactions of free radicals.
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Hibiscus sabdariffa (HS) has gained attention as an anti-hypertensive agent. In the present study, we hypothesizedthat anthocyanins from HS may attenuate salt-induced hypertension in rats by suppressing the components of renin-angiotensin-aldosterone system (RAAS). Hypertension was induced in the rats by adding 8% NaCl to their constituted dietfor six weeks. Wistar rats (n=5 each) were randomly divided into seven groups. Group 1 was the normotensive control groupand was fed with normal rat chew and water ad libitum; groups 2 and 3 served as hypertensive control (negative untreatedand positive treated with captopril 30mg/kg respectively); groups 4, 5, and 6 served as treatment groups and wereadministered with graded doses of anthocyanins( 50, 100, 200mg/kg respectively) while group 7 received both 100mganthocyanins and 30mg captopril per day for 4 weeks. Using HPLC, anthocyanins were isolated from HS calyx followingstandard protocol. Anthocyanins significantly (p<0.05) reduced blood pressure and heart rate in hypertensive rats in a dose-dependent manner. The blood pressure reduction by anthocyanins was associated with a reduction in serum ACE and plasmaaldosterone in the hypertensive rats. The effects of anthocyanins on blood pressure and biomarkers of RAAS were similar tothose of captopril, a reference anti-hypertensive drug. The results suggest that anthocyanins exerts a significant anti-hypertensive potency on rats, probably mediated by the reduction in components of the RAAS. Keywords: hypertension, anthocyanins, renin, aldosterone, captopril, rats.
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The antioxidative effects of vegetable extracts were evaluated using linoleic acid emulsion and liposomal phospholipid suspension systems. First, the antioxidative activities of water, ethanol and 2% metaphosphoric acid extracts of the vegetables were investigated by measuring the rate of oxygen consumption in the peroxidation of linoleic acid initiated by a radical generator, 2,2′‐azobis(2‐amidinopropane) dihydrochloride (AAPH), with a Clark electrode in the absence of metal chelators. Ethanol extracts of moroheiya and perilla exhibited the highest antioxidative activities. Without metal chelators, 12 ethanol extracts and one water extract acted as prooxidants, and this phenomenon could be attributed to the prooxidant action of ascorbic acid in the presence of free transition metal ions. Next, peroxyl radical‐scavenging activities of vegetable extracts were examined by adding a metal chelator, diethylenetriaminepentaacetic acid (DTPA), to the linoleic acid emulsion system. The results were compared with their antioxidative activities in phospholipid bilayers by measuring the inhibition of lipid peroxidation in large unilamellar vesicles composed of egg yolk phosphatidylcholine (PC). A good correlation was observed between the antioxidative activities obtained from these two systems. The antioxidative activities in the liposomal phospholipid suspension system correlated with total contents of ascorbic acid and polyphenols in vegetable extracts. © 1999 Society of Chemical Industry
Article
The antioxidative effects of vegetable extracts were evaluated using linoleic acid emulsion and liposomal phospholipid suspension systems. First, the antioxidative activities of water, ethanol and 2% metaphosphoric acid extracts of the vegetables were investigated by measuring the rate of oxygen consumption in the peroxidation of linoleic acid initiated by a radical generator, 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH), with a Clark electrode in the absence of metal chelators. Ethanol extracts of moroheiya and perilla exhibited the highest antioxidative activities. Without metal chelators, 12 ethanol extracts and one water extract acted as prooxidants, and this phenomenon could be attributed to the prooxidant action of ascorbic acid in the presence of free transition metal ions. Next, peroxyl radical-scavenging activities of vegetable extracts were examined by adding a metal chelator, diethylenetriaminepentaacetic acid (DTPA), to the linoleic acid emulsion system. The results were compared with their antioxidative activities in phospholipid bilayers by measuring the inhibition of lipid peroxidation in large unilamellar vesicles composed of egg yolk phosphatidylcholine (PC). A good correlation was observed between the antioxidative activities obtained from these two systems. The antioxidative activities in the liposomal phospholipid suspension system correlated with total contents of ascorbic acid and polyphenols in vegetable extracts.© 1999 Society of Chemical Industry
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This study was aimed at determining the antioxidant activity of commercial grape juices in inhibiting the copper-catalyzed oxidation of human low-density lipoproteins (LDL) in vitro and at relating this activity to the phenolic composition of the juices. This work also evaluated the effect of vitamin C on this antioxidant activity. When standardized to a total phenolic concentration of 10 μM gallic acid equivalents (GAE), samples of grape juices inhibited LDL oxidation from 62 to 75%. White grape juices inhibited LDL oxidation on the average by 72%, Concord purple grape juice by 67%, and grape juice blends (mixture of white and Concord grape juice) by 63%. Vitamin C had no significant effect on the antioxidant activity of the grape juices tested. The antioxidant activity of Concord juice samples was related to their anthocyanin levels, while that of the white grape juices was related to their levels of flavan-3-ols and hydroxycinnamates, as determined by HPLC. On the basis of the same total phenolic concentration, the antioxidant activity of grape juices toward LDL oxidation was comparable to that of several California red wine. However, based on their undiluted total phenolic concentration, the Concord and blends of grape juices had comparable activity to that of the red wines, while the white grape juices were less active.
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The relation between antioxidant activity and anthocyanin was determined in Roselle (Hibiscus sabdariffa L.) petals. Petals from Roselle, cultivar F141, were collected and dried in Taitung, Taiwan. Roselle extract was prepared by extracting dried Roselle petals in boiling water. The relation between the anthocyanin color and antioxidant capacity was elucidated by comparing absorbance at 520 nm, with ferric reducing ability of plasma (FRAP), oxygen radical absorbance capacity (ORAC) and total antioxidant status (TAS) antioxidant assays. The results showed that the antioxidant capacity of Roselle extract increased when extraction time or weight of petals increased. The FRAP assay showed a linear relationship with anthocyanin as determined at 520 nm. Comparisons between FRAP and ORAC or FRAP and TAS assays gave a linear relation. These results suggest that anthocyanin is the major source of antioxidant capacity in Roselle extract. Further purification using Amberlite XAD-2 and HPLC indicated that anthocyanin and a brown pigment in the extract account for about 51 and 24% of the antioxidant capacity, respectively. Under different processing temperatures and storage periods, anthocyanin content declines. However, other phenolic compounds increase and overall there is only a relatively small decrease in total phenolic compounds and antioxidant activity.
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The antioxidant activity of the hexane, ethyl acetate and methanol extracts of three varieties of sorrel (Hibiscus sabdariffa), as well as their potential for reducing blood viscosity, were studied in vitro. The samples screened were two red [(traditional red (TRED) and early bearing red (ERED)] and one white (WHTE) mature Hibiscus varieties. Antioxidant activity was measured by fluorescence spectroscopy using a model liposome system. Cyclooxygenase inhibitory activity was measured using cyclooxygenase (COX-1 and COX-2) enzymes by monitoring the rate of oxygen uptake in prostaglandin synthesis. Antioxidant activity was the highest overall in the red varieties compared to the white. The methanol extract from the three varieties had the highest activity. The methanol and ethyl acetate extracts of the three varieties of sorrel showed higher COX-1 enzyme inhibition than COX-2 and therefore had high potential to decrease blood viscosity. There was no COX-1 or COX-2 inhibition in the hexane extract. These findings support the ethnomedicinal use of H. sabdariffa in Africa and the Caribbean for the treatment of cardiovascular disease and hypertension.
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Different cultivars of four Vaccinium species [Vaccinium corymbosum L (Highbush), Vaccinium ashei Reade (Rabbiteye), Vaccinium angustifolium (Lowbush), and Vaccinium myrtillus L (Bilberry)] were analyzed for total phenolics, total anthocyanins, and antioxidant capacity (oxygen radical absorbance capacity, ORAC). The total antioxidant capacity of different berries studied ranged from a low of 13.9 to 45.9 micromole Trolox equivalents (TE)/g of fresh berry (63.2-282.3 micromole TE/g of dry matter) in different species and cultivars of Vaccinium. Brightwell and Tifblue cultivars of rabbiteye blueberries were harvested at 2 times, 49 days apart. Increased maturity at harvest increased the ORAC, the anthocyanin, and the total phenolic content. The growing location (Oregon vs Michigan vs New Jersey) did not affect ORAC, anthocyanin or total phenolic content of the cv. Jersey of highbush blueberries. A linear relationship existed between ORAC and anthocyanin (r(xy) = 0.77) or total phenolic (r(xy) = 0.92) content. In general, blueberries are one of the richest sources of antioxidant phytonutrients of the fresh fruits and vegetables we have studied.
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In this study, chemical and mineral composition of the calyces of green, red and dark red roselle were evaluated. There was no significant difference in crude protein of green (17.9%) and red (17.4%) coloured roselle calyces. Crude fibre (11.2%), ascorbic acid (86.5mg/~OOg) and sodium (9.5mg/lOOg) contents of green coloured calyx were significantly higher than other calyx samples. However, dark red calyx was significantly higher in ash (6.8%) and potassium (2320mg/100g) contents than the other two calyces. Also, there was no significant differences in calcium, magnesium and zinc contents of red and dark red coloured roselle calyces at P<O.05. Roselle calyces appeared to be cheap source of vegetable protein, fat and minerals therefore its consumption should be encouraged.
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The antioxidant and prooxidant behavior of flavonoids and the related activity-structure relationships were investigated in this study using the oxygen radical absorbance capacity assay. Three different reactive species were used in the assay: 2,2'-azobis(2-amidino-propane) dihydrochloride, a peroxyl radical generator; Cu(2+)-H2O2, mainly a hydroxyl radical generator; and Cu2+, a transition metal. Flavonoids including flavones, isoflavones, and flavanones acted as antioxidants against peroxyl and hydroxyl radicals and served as prooxidants in the presence of Cu2+. Both the antioxidant and the copper-initiated prooxidant activities of a flavonoid depend upon the number of hydroxyl substitutions in its backbone structure, which has neither antioxidant nor prooxidant action. In general, the more hydroxyl substitutions, the stronger the antioxidant and prooxidant activities. The flavonoids that contain multiple hydroxyl substitutions showed antiperoxyl radical activities several times stronger than Trolox, an alpha-to copherol analogue. The single hydroxyl substitution at position 5 provides no activity, whereas the di-OH substitution at 3' and 4' is particularly important to the peroxyl radical absorbing activity of a flavonoid. The conjugation between rings A and B does not affect the antioxidant activity but is very important for the copper-initiated prooxidant action of a flavonoid. The O-methylation of the hydroxyl substitutions inactivates both the antioxidant and the prooxidant activities of the flavonoids.
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Fresh strawberries (Fragaria x ananassa Duch.), raspberries (Rubus idaeus Michx.), highbush blueberries (Vaccinium corymbosum L.), and lowbush blueberries (Vaccinium angustifolium Aiton) were stored at 0, 10, 20, and 30 degrees C for up to 8 days to determine the effects of storage temperature on whole fruit antioxidant capacity (as measured by the oxygen radical absorbing capacity assay, Cao et al., Clin. Chem. 1995, 41, 1738-1744) and total phenolic, anthocyanin, and ascorbate content. The four fruit varied markedly in their total antioxidant capacity, and antioxidant capacity was strongly correlated with the content of total phenolics (0.83) and anthocyanins (0.90). The antioxidant capacity of the two blueberry species was about 3-fold higher than either strawberries or raspberries. However, there was an increase in the antioxidant capacity of strawberries and raspberries during storage at temperatures >0 degrees C, which was accompanied by increases in anthocyanins in strawberries and increases in anthocyanins and total phenolics in raspberries. Ascorbate content differed more than 5-fold among the four fruit species; on average, strawberries and raspberries had almost 4-times more ascorbate than highbush and lowbush blueberries. There were no ascorbate losses in strawberries or highbush blueberries during 8 days of storage at the various temperatures, but there were losses in the other two fruit species. Ascorbate made only a small contribution (0.4-9.4%) to the total antioxidant capacity of the fruit. The increase observed in antioxidant capacity through postharvest phenolic synthesis and metabolism suggested that commercially feasible technologies may be developed to enhance the health functionality of small fruit crops.
Article
Fruits and leaves from different cultivars of thornless blackberry (Rubus sp.), red raspberry (Rubus idaeus L.), black raspberry (Rubus occidentalis L.), and strawberry (Fragaria x ananassa D.) plants were analyzed for total antioxidant capacity (oxygen radical absorbance capacity, ORAC) and total phenolic content. In addition, fruits were analyzed for total anthocyanin content. Blackberries and strawberries had the highest ORAC values during the green stages, whereas red raspberries had the highest ORAC activity at the ripe stage. Total anthocyanin content increased with maturity for all three species of fruits. Compared with fruits, leaves were found to have higher ORAC values. In fruits, ORAC values ranged from 7.8 to 33.7 micromol of Trolox equivalents (TE)/g of fresh berries (35. 0-162.1 micromol of TE/g of dry matter), whereas in leaves, ORAC values ranged from 69.7 to 182.2 micromol of TE/g of fresh leaves (205.0-728.8 micromol of TE/g of dry matter). As the leaves become older, the ORAC values and total phenolic contents decreased. The results showed a linear correlation between total phenolic content and ORAC activity for fruits and leaves. For ripe berries, a linear relationship existed between ORAC values and anthocyanin content. Of the ripe fruits tested, on the basis of wet weight of fruit, cv. Jewel black raspberry and blackberries may be the richest source for antioxidants. On the basis of the dry weight of fruit, strawberries had the highest ORAC activity followed by black raspberries (cv. Jewel), blackberries, and red raspberries.
Article
Anthocyanins from tart cherries, Prunus cerasus L. (Rosaceae) cv. Balaton and Montmorency; sweet cherries, Prunus avium L. (Rosaceae); bilberries, Vaccinum myrtillus L. (Ericaceae); blackberries, Rubus sp. (Rosaceae); blueberries var. Jersey, Vaccinium corymbosum L. (Ericaceae); cranberries var. Early Black, Vaccinium macrocarpon Ait. (Ericaceae); elderberries, Sambucus canadensis (Caprifoliaceae); raspberries, Rubus idaeus (Rosaceae); and strawberries var. Honeoye, Fragaria x ananassa Duch. (Rosaceae), were investigated for cyclooxygenase inhibitory and antioxidant activities. The presence and levels of cyanidin-3-glucosylrutinoside 1 and cyanidin-3-rutinoside 2 were determined in the fruits using HPLC. The antioxidant activity of anthocyanins from cherries was comparable to the commercial antioxidants, tert-butylhydroquinone, butylated hydroxytoluene and butylated hydroxyanisole, and superior to vitamin E, at a test concentration of 125 microg/ml. Anthocyanins from raspberries and sweet cherries demonstrated 45% and 47% cyclooxygenase-I and cyclooxygenase-II inhibitory activities, respectively, when assayed at 125 microg/ml. The cyclooxygenase inhibitory activities of anthocyanins from these fruits were comparable to those of ibuprofen and naproxen at 10 microM concentrations. Anthocyanins 1 and 2 are present in both cherries and raspberry. The yields of pure anthocyanins 1 and 2 in 100 g Balaton and Montmorency tart cherries, sweet cherries and raspberries were 21, 16.5; 11, 5; 4.95, 21; and 4.65, 13.5 mg, respectively. Fresh blackberries and strawberries contained only anthocyanin 2 in yields of 24 and 22.5 mg/100 g, respectively. Anthocyanins 1 and 2 were not found in bilberries, blueberries, cranberries or elderberries.
Article
The effect of aqueous extract of petals of Hibiscus sabdariffa (HS) on the established stages of 2-Kidney, 1-Clip renovascular hypertension was investigated in Sprague-Dawley rats. Renovascular hypertension was induced by subjecting the animals to left renal artery clamping using a 0.2mm silver clip under ether anesthesia. Sham-operated (Sh-Op) rats served as controls. Six weeks after renal artery clamping, one group of hypertensive rats (blood pressure (BP) >140 mmHg) received HS (250 mg/kg/day) in drinking water (2K-1C+HS). The second group (2K-1C) and the sham-operated (Sh-Op) controls, received drinking water. BP was monitored weekly using rat-tail plethysmography. After 8 weeks, 2K-1C+HS had a reduction in systolic BP (139.6+/-1.6 mmHg) compared to 2K-1C (174+/-2.4 mmHg, n=5; P<0.001). No significant difference was found in BP of 2K-1C+HS and Sh-Op (139.6+/-1.6 mmHg versus 132+/-3.4 mmHg). A reduction in heart rate in 2K-1C+HS was observed (388+/-3.7 bpm versus 444+/-6.8 bpm in 2K-1C and 416+/-9.3 in Sh-Op, n=5; P<0.001). The hearts of 2K-1C were heavier than those of 2K-1C+HS (0.74+/-0.03 g versus 0.66+/-0.03 g, n=5; P<0.05). Cardiac weight of 2K-1C+HS was comparable to those of Sh-Op (0.57+/-0.04 g). Serum creatinine and plasma electrolytes were not different from controls. This study suggests that HS exhibits antihypertensive and cardioprotective effects in vivo and supports the public belief that HS may be a useful antihypertensive agent.
Article
In order to compare the antihypertensive effectiveness and tolerability of a standardized extract from Hibiscus sabdariffa with captopril, a controlled and randomized clinical trial was done. Patients from 30 to 80 years old with diagnosed hypertension and without antihypertensive treatment for at least 1 month before were included. The experimental procedure consisted of the administration of an infusion prepared with 10 g of dry calyx from H. sabdariffa on 0.51 water (9.6 mg anthocyanins content), daily before breakfast, or captopril 25 mg twice a day, for 4 weeks. The outcome variables were tolerability, therapeutic effectiveness (diastolic reduction > or = 10 mm Hg) and, in the experimental group, urinary electrolytes modification. Ninety subjects were included, 15 withdrew from the study due to non-medical reasons; so, the analysis included 39 and 36 patients from the experimental and control group, respectively. The results showed that H. sabdariffa was able to decrease the systolic blood pressure (BP) from 139.05 to 123.73mm Hg (ANOVA p < 0.03) and the diastolic BP from 90.81 to 79.52mm Hg (ANOVA p < 0.06). At the end of the study, there were no significant differences between the BP detected in both treatment groups (ANOVA p > 0.25). The rates of therapeutic effectiveness were 0.7895 and 0.8438 with H. sabdariffa and captopril, respectively (chi2, p > 0.560), whilst the tolerability was 100% for both treatments. A natriuretic effect was observed with the experimental treatment. The obtained data confirm that the H. sabdariffa extract, standardized on 9.6mg of total anthocyanins, and captopril 50 mg/day, did not show significant differences relative to hypotensive effect, antihypertensive effectiveness, and tolerability.
Hibiscus sabdariffa. (online) Available
  • J A Duke
Duke, J.A., 2002. Hibiscus sabdariffa. (online) Available: http://www.hort.purdue. edu/newcrop/duke_energy/Hibiscus_sabdariffa.html [Accessed May 2002]
Anthocyanins: Char-acterization and Measurement with UV–visible Spectroscopy, in Current Protocols in Food Analytical Chemistry
  • M M Giusti
  • R E Wrolstad
Giusti, M.M., Wrolstad, R.E., 2000. In: Wrolstad, R.E. (Ed.), Anthocyanins: Char-acterization and Measurement with UV–visible Spectroscopy, in Current Protocols in Food Analytical Chemistry. John Wiley & Sons, New York, NY, Unit F1.2.1-13.
Renewed interest in Roselle (Hibiscus sabdariffa), the long forgotten “Florida Cranberry”
  • Morton
Morton, J., 1974. Renewed interest in Roselle (Hibiscus sabdariffa), the long forgotten ''Florida Cranberry''. Proceedings of the Florida State Horticultural Society 87, 415–425.