Positive effects of durian fruit at different stages of ripening on the hearts and livers of rats fed diets high in cholesterol

ArticleinEuropean Journal of Integrative Medicine 3(3) · September 2011with 1,305 Reads 
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Abstract
Aim of the study: Diets containing high cholesterol levels led to atherosclerosis damage in the livers and hearts of rats. The aim of this study was to investigate the possible positive effects of durian fruit against high-cholesterol diets. Materials and methods: Durians at various stages of ripening (young, mature, ripe and overripe) were chosen for in vitro and in vivo studies. In the in vivo study 36 male Wistar rats were divided into 6 groups and supplemented with cholesterol and durians. The bioactivity in vitro, plasma lipids, antioxidant activity, liver enzymes and histopathology of the aorta and liver were analyzed. Results: Polyphenols and flavonoids were significantly higher in the overripe durian, while quercetin, ascorbic acid and anthocyanins were more abundant in the ripe fruit and tannins - in mature samples (P<0.05). The highest antioxidant potential was in overripe fruit and only the value of FRAP - in ripe durian samples (P<0.05). The interaction between polyphenol extracts of ripe durian and BSA had a strong ability comparable to that of quercetin - to quench the intrinsic fluorescence of BSA by forming complexes. The main histopathological changes were detected in the liver and aorta of rats fed a high-cholesterol diet without fruit supplementation. These changes were minor in rats of Chol/DRipe (P<0.05). Conclusion: Durian at different stages of ripening, especially ripe durian, constitute an excellent source of effective natural compounds with antioxidant and health-protective activity in general and liver and heart-protective effect in cholesterol fed rats in particular.

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  • ... Durian (Durio zibethinus Murr.) is an exotic fruit with a high bioactive content that has the potential to have pharmacological effects . Fruit peels are one part of durian which can be developed as a raw material for herbal medicine because it has antioxidant, antidiabetic, and antihypercholesterol pharmacological effects (Batubara et al., 2009;Batubara;2011;Muhtadi et al., 2014;Leontowicz et al., 2011). Muhtadi et al., (2016) reported that durian fruit peels were proven to reduce cholesterol levels in blood serum of rats equivalent to that of Cholesterolamine as a positive control. ...
    ... Leontowicz et al. (2008) stated that durian can significantly inhibit the increase of plasma lipids. Subsequent research Leontowicz et al.( 2011) reported that inhibition of increased lipid was due to the role of antioxidant activity produced by the active polyphenol and flavonoid compounds. ...
    ... This compound had the potential antioxidant activity (Muhtadi et al., 2014). Leontowicz et al. (2011) examined Monthong cultivar originating from eastern Thailand, showing antioxidant activity of 1.12 µMTE/g. Batubara (2011) used durian fruit peels originating from Indonesia in their research and reported the results of antioxidant activity of 61.57 ...
  • ... Durian is also rich in polyphenols such as flavonoids (flavanones, flavonols, flavones, flavanols, anthocyanins), phenolic acids (cinnamic acid and hydroxybenzoic acid), tannins, and other bioactive components such as carotenoids and ascorbic acid [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. Current epidemiological studies have suggested that polyphenols decrease the risk of chronic diseases (e.g., cardiovascular diseases, cancers and diabetes) [26][27][28][29][30]. ...
    ... The energy content of durian is in the range of 84-185 kcal per 100 g fresh weight (FW) ( Table 1) [6,18,19]. This range is somewhat similar to that of the United States Department of Agriculture (USDA), Malaysian, and Indonesian food composition databases [20][21][22]. Durian aril of the Thailand variety of Kradum showed the highest energy content at 185 kcal compared with other durian varieties [6,12,13]. Indonesian variety of Hejo showed the lowest energy content at 84 kcal per 100 g FW of durian aril [6]. ...
    ... Durian is also a source of iron, copper, and zinc with the range of 0.18 to 1.90, 0.12 to 0.27 and 0.15 to 0.45 mg per 100 g FW, respectively. The Thailand variety of Chanee showed the highest level of iron, zinc and potassium among the studied durian [12,[19][20][21][22]29]. Durian also contains vitamin A, different types of vitamin B, and vitamin E [13][14][15][31][32][33]. ...
    Article
    Full-text available
    Durian (Durio zibethinus Murr.) is an energy-dense seasonal tropical fruit grown in Southeast Asia. It is one of the most expensive fruits in the region. It has a creamy texture and a sweet-bitter taste. The unique durian flavour is attributable to the presence of fat, sugar, and volatile compounds such as esters and sulphur-containing compounds such as thioacetals, thioesters, and thiolanes, as well as alcohols. This review shows that durian is also rich in flavonoids (i.e., flavanols, anthocyanins), ascorbic acid, and carotenoids. However, limited studies exist regarding the variation in bioactive and volatile components of different durian varieties from Malaysia, Thailand, and Indonesia. Experimental animal models have shown that durian beneficially reduces blood glucose and cholesterol levels. Durian extract possesses anti-proliferative and probiotics effects in in vitro models. These effects warrant further investigation in human interventional studies for the development of functional food.
  • ... Durian (Scientific name: Durio zibethinus; family: Bombacaceae; Genus: Durio) is a climacteric, seasonal tropical fruit of Southeast Asia (Malaysia, Thailand, Philippines and Indonesia). The ripe durian fruit owing to its unique taste and aroma, is considered locally as 'king of fruits' (Berry, 1979;Leontowicz et al., 2011;Srianta, Hendrawan, Kusumawati, & Blanc, 2012;Subhadrabandhu & Ketsa, 2001;Voon, Hamid, Rusul, Osman, & Quek, 2007b). ...
    ... These bioactive compounds possess high potential to be used as a therapeutic agent. They can be of help to treat patients suffering from diabetes mellitus (help in regulating secretion of insulin) as well as be of use to treat certain cardiovascular diseases (by reducing serum cholesterol) (Gorinstein et al., 2011;Haruenkit et al., 2010;Leontowicz et al., 2007Leontowicz et al., , 2008Leontowicz et al., , 2011Roongpisuthipong, Banphotkasem, Komindr, & Tanphaichitr, 1991). Some of the major bioactive compounds such as anthocyanins, carotenoids, polyphenols, flavonoids, and others are reported to be present in ample amounts in durian fruit. ...
    ... Durian flesh as well as its wastes (hull/skin) is reported to have abundance of therapeutic benefits such as: possessing anti-diabetic properties, anti-hyperlipidemic effects, anti-proliferative activity and antimicrobial activities (Chansiripornchai, Pongsamart, Nakchat, Pramatwinai, & Rangsipipat, 2005;Gorinstein et al., 2011;Haruenkit et al., 2010;Leontowicz et al., 2008Leontowicz et al., , 2011Pholdaeng & Pongsamart, 2010;Pongsamart, Lipipun, Jesadanont, & Pongwiwatana, 2006;Pongsamart, Lipipun, Nantawanit, & Lertchaiporn, 2005). Durian fruit consumption has also been reported to decrease metabolic syndromes, hyperlipidemia, hyperglycemia, cardiovascular diseases and inflammation including that of oxidative stress (Leontowicz et al., 2007;Roongpisuthipong et al., 1991). ...
  • ... A high correlation was found among the contents of total polyphenols, vitamin C, and antioxidant activity in kiwifruit A. deliciosa and A. eriantha [11,[14][15][16]. Consumption of fruit plays a special role in the prevention of atherosclerosis and cardiovascular diseases [8,10,17,18], and exogenous cholesterol can lead to liver and heart damage in animals [19][20][21][22]. Atherosclerotic lesions were found in the aorta of rats [17,18], mice [19], and rabbits [20] fed a cholesterol-enriched diet. ...
    ... Consumption of fruit plays a special role in the prevention of atherosclerosis and cardiovascular diseases [8,10,17,18], and exogenous cholesterol can lead to liver and heart damage in animals [19][20][21][22]. Atherosclerotic lesions were found in the aorta of rats [17,18], mice [19], and rabbits [20] fed a cholesterol-enriched diet. From our previous studies, we know that the Hayward variety of kiwifruit, given as part of an atherogenic diet, influenced the increase of plasma antioxidant capacity. ...
    ... Activity of ALP in blood increased in rats fed the diets with cholesterol in comparison to the control group, but did not change with supplementation of fruits. Similar results were obtained in another study on durian (5%) and kiwifruit Hayward (5%) in rats [10,17]. High-amylase activity affects the high glucose level in rat's blood from ChGeneva and other groups of rats (ChBidan org, ChJumbo). ...
    Article
    There are no published results focusing on the study of hardy kiwifruit as a supplementation to the atherogenic diet. We hypothesized that hardy kiwifruit (Actinidia arguta (A. arguta)) from Poland possess better pro-healthy action than two Asian varieties (Hayward and Bidan). We tested this hypothesis by measuring the metabolic reactions of rats loaded with 1% cholesterol and supplemented with 5% of hardy kiwifruit (A. arguta), Hayward, or Bidan in their diets. The experiment was performed on 71 male Wistar rats. Cholesterol showed a significant impact on the rise of liver somatic index, while lipid profile improved by decreasing the levels of TC, LDL-C, TC/HDL-C, AI, TG, and increasing HDL-C in the serum of rats (P < .05). Total plasma antioxidant capacity determined by ABTS, FRAP, and DPPH assays was increased. ALP in rat serum was higher in groups receiving cholesterol diets and kiwifruit. A decrease in fibrinogen as well as prolonged prothrombin time and a reduction of the MPO in serum were estimated. The smallest percentage of lesions in the aortic arch was in the ChGeneva, ChWeiki, and ChAnna. Similarly, the smallest fatty liver disease was recorded in the ChGeneva and ChAnna groups. The distribution of lipids in the liver from these groups had a character of “mosaic,” in hardy/mini kiwifruit (Jumbo), Hayward, and Bidan was distributed uniformly. The longest villi were in ChWeiki, and significantly lower in ChHayward and ChBidan. The present results support our hypothesis that A. arguta showed better pro-health impacts in rats loaded with cholesterol than Hayward and Bidan kiwifruit, and, for the first time, the positive nutritional effects of supplemented A. arguta for hypercholesterolemia are noted.
  • ... At this time of globalization, many tropical fruits can be found at the markets of Europe and North America. Most customers are not familiar with the nutritional values of these fruits in spite of the fact that the consumption of new exotic fruits, with their high nutritional and sensory values, has significantly increased in the past few years (Park et al., 2009;Poovarodom et al., 2010;Haruenkit et al., 2010;Dembitsky et al., 2011;Gorinstein et al., 2011;Leontowicz et al., 2011). ...
    ... At this time of globalization, many tropical fruits can be found at the markets of Europe and North America. Most customers are not familiar with the nutritional values of these fruits in spite of the fact that the consumption of new exotic fruits, with their high nutritional and sensory values, has significantly increased in the past few years (Park et al., 2009;Poovarodom et al., 2010;Haruenkit et al., 2010;Dembitsky et al., 2011;Gorinstein et al., 2011;Leontowicz et al., 2011). ...
    ... Flavonoids, flavanols, tannins, anthocyanins, quercetin and ascorbic acid were determined spectroscopically as previously described. The antioxidant potentials were estimated by four complementary assays: ferric reducing antioxidant power (FRAP); 2,2-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) diamonium salt (ABTS ·+ ); 1-diphenyl-2-picrylhydrazyl method (DPPH); and cupric reducing antioxidant capacity (CUPRAC) (Park et al., 2009;Haruenkit et al., 2010;Poovarodom et al., 2010;Gorinstein et al., 2011;Leontowicz et al., 2011). The presence of polyphenols in the fruit extracts and the interaction between polyphenols and bovine serum albumin (BSA) were studied by Fourier Transform Infrared (FT-IR) spectroscopy (Nicolet iS 10 FT-IR Spectrometer) and by 3-D fluorescence (3D-FL). ...
    Article
    During the past two decades our international scientific group investigated in vitro the physicochemical and nutritional characteristics of some cultivars of durian at various stages of ripening, mangosteen and new cultivars of snake fruit in comparison with widely used avocado, kiwifruit and mango, and in vivo their influence on laboratory animals. The main objective of the present study was to screen and compare the properties of water and ethanol extracts of selected exotic fruits and the influence of their physiologically active compounds on human health. The bioactive compounds were extracted with water and ethanol using similar procedures as are used in pharmaceutical applications and daily fruit consumption. Various analytical methods were used to detect biologically active metabolites derived from exotic fruits (polyphenols, flavonoids, flavanols, tannins, anthocyanins and ascorbic acid), antioxidant radical scavenging assays (DPPH, FRAP, CUPRAC, and ABTS), Fourier transform infrared (FT-IR) and ultraviolet (UV) spectroscopy, two (2D-FL) and threedimensional (3D-FL) fluorimetry. The correlation between the polyphenols and other bioactive compounds, and their antioxidant activities, is reported for the studied fruit extracts. The properties of the soil, where the investigated fruits were grown, were studied as well. Supplementation of diets with exotic fruits positively affected the plasma lipid profile and antioxidant activity in rats fed cholesterol-containing diets. The interaction between drugs and serum albumin plays an important role in the distribution and metabolism of drugs. The properties of polyphenol extracts of exotic fruits showed the ability to quench serum albumin by forming complexes similar with the ones formed between the proteins and pure flavonoids such as catechin and quercetin. In conclusion, new application of fluorimetry and FTIR spectroscopy for rapid estimation of the quality of exotic fruits in particular and for any fruits and vegetables in general is presented. It is necessary to promote a consumption of exotic fruits (a rich source of natural antioxidants) as a supplement to everyday human diet and for pharmaceutical applications.
  • ... Phenolic acids are antioxidant molecules that are in the limelight of clinical and epidemiological research because their demonstrated value as the antioxidant components of fruits and vegetables [1]. These foods also contain a wide variety of antioxidant bioactive compounds (carotenoids, vitamins, among others) that provide health benefits to consumers2345. Mango (Mangifera indica L.) fruit is an excellent source of dietary antioxidants, such as ascorbic acid, carotenoids, and especially phenolic compounds [6]. ...
    ... However, information about phenolic acids and their interactions on the AOXC is scarce. A previous study reported individual phenolic changes during ripening and affected to different extent the AOXC in durian (Durio sp.) fruit [5]. Each phenolic compound has a different AOXC depending on its structure, number of aromatic and hydroxyl groups and their distribution in the structure [12,13]. ...
    Article
    Full-text available
    Phenolic compounds are known to have antioxidant capacity; however, there is little information about molecular interactions between particular phenolics found in fruits at different developmental stages. Therefore, the total antioxidant capacity of the phenolic compounds of a fruit may not correspond to the sum of individual antioxidant capacity given by antioxidants from that tissue. In this study, individual antioxidant capacity and the interactions of four major phenolic compounds (chlorogenic, gallic, protocatechuic and vanillic acid) found in 'Ataulfo' mango pulp were tested using the DPPH assay. Significant synergism was found in the majority of the all combinations, as well as the combination of the four phenolics. However, antagonism was also observed between some molecules. This work demonstrated particular interactions that may occur in a complex environment within the complex framework of a natural food. The present results may also assist in the future design of functional foods or ingredients based on their antioxidant activity and their synergistic or antagonist interactions.
  • ... An increase of TAC in the plasma of rats was presented also in our previous papers concerning supplementation of a cholesterol diet with 5% persimmon 35 or 5% durian. 36 It can be assumed that the addition of exotic fruits to the diet of 1% cholesterol improves endogenous antioxidant system of the body and increases the body's overall antioxidant capacity. The biological activity of polyphenols depends on their bioavailability. ...
    ... These changes occurred in the aortic arch (lesions) and in the liver (steatosis), as examined by us in exotic fruits (persimmon, durian), and reduced their range. 35,36 In conclusion, organic kiwifruits have higher amounts of bioactive compounds and antioxidant capacity than conventionally grown kiwifruits. Ethylene treatment increases the bioactivity of kiwifruit. ...
    Article
    Kiwifruit is a subtropical fruit that is very popular among consumers. Kiwifruit 'Hayward' ( Actinidia deliciosa C.F. Liang et A.R. Ferguson) is an important source of bioactive compounds and possesses high antioxidant capacity, but its value can be changed during ripening. The aim of this study was to compare the levels of total polyphenols (TP), ascorbic acid (AA), and total antioxidant capacities (TACs) of ethylene-treated and nontreated kiwifruits 'Hayward' from conventional and organic farming. The influence of these fruits on lipid profile, TAC, and liver enzymes in plasma of rats fed diets with cholesterol was studied. Ethylene treatment shortened the ripening of kiwifruits. Ethylene-treated kiwifruits from organic farming (OHE) have the highest contents of TP and TAC. The experiment in vivo was performed during 33 days on male Wistar rats (111 ± 5 g), divided into six groups: one without cholesterol, control (C), and five groups with 1% of cholesterol (Chol). Four groups with cholesterol were supplemented with 5% of lyophilized kiwifruits: ethylene treated, organic (Chol/OHE) or conventional (Chol/CHE); and untreated, organic (Chol/OHC) or conventional (Chol/CHC). Cholesterol diets supplemented with kiwifruit influenced the palatability and feed intake, body gain, and FER. Diets containing kiwifruits significantly influenced the decrease of TG (61%), TC (29%), LDL-C (38%), atherogenic index TC/HDL-C (25%), and atherogenic index (AI, 32%), without differences between treatments. A significant increase of TAC in plasma of rats fed kiwifruit was obtained by DPPH (18%), FRAP (55%), and ABTS (55%). Aspartate aminotransferase (AST) activity in serum was significantly lower for all groups with kiwifruit supplementation. Alanine aminotransferase (ALT) was lower only in diet groups supplemented with conventional fruits in comparison with the cholesterol group. Glucose levels were higher in groups with kiwifruit supplementation than in C and Chol groups. Supplementation of Chol groups with organic kiwifruits influenced the prothrombin index and significantly decreased the amount of platelets (PLT) in blood. In conclusion, studied kiwifruit 'Hayward' can be a very good ingredient of the diet, especially for patients suffering from hypercholesterolemia and with other cardiovascular diseases, but not for diabetic patients.
  • ... Phenolic acids are antioxidant molecules that are in the limelight of clinical and epidemiological research because their demonstrated value as the antioxidant components of fruits and vegetables [1]. These foods also contain a wide variety of antioxidant bioactive compounds (carotenoids, vitamins, among others) that provide health benefits to consumers [2][3][4][5]. Mango (Mangifera indica L.) fruit is an excellent source of dietary antioxidants, such as ascorbic acid, carotenoids, and especially phenolic compounds [6]. The health benefits have been demonstrated in vivo because of their remarkable antioxidant capacity (AOXC) [7,8]. ...
    ... However, information about phenolic acids and their interactions on the AOXC is scarce. A previous study reported individual phenolic changes during ripening and affected to different extent the AOXC in durian (Durio sp.) fruit [5]. ...
    Article
    Full-text available
    Phenolic compounds are known to have antioxidant capacity; however, there is little information about molecular interactions between particular phenolics found in fruits at different developmental stages. Therefore, the total antioxidant capacity of the phenolic compounds of a fruit may not correspond to the sum of individual antioxidant capacity given by antioxidants from that tissue. In this study, individual antioxidant capacity and the interactions of four major phenolic compounds (chlorogenic, gallic, protocatechuic and vanillic acid) found in 'Ataulfo' mango pulp were tested using the DPPH assay. Significant synergism was found in the majority of the all combinations, as well as the combination of the four phenolics. However, antagonism was also observed between some molecules. This work demonstrated particular interactions that may occur in a complex environment within the complex framework of a natural food. The present results may also assist in the future design of functional foods or ingredients based on their antioxidant activity and their synergistic or antagonist interactions.
  • ... According to Beever and Hopkirik [32] kiwifruit is a valuable source of vitamin C, but it contains a small amount of polyphenols [33]. As it was presented in our study polyphenol content in kiwifruits amounted from 7.1 (CHC) to 10.1 mg GAE/g DM and was more than twice higher as in other exotic fruits such as durian [34] and persimmon 'Jiro' [35]. Amodio et al. [21] showed that organic kiwifruit has a significantly higher polyphenol content and antioxidant capacity than in fruits from conventional farming. ...
  • ... Durian acts as an antioxidant [9] and antiproliferative [10]. The content of polyphenols and flavonoids can inhibit rise high enough plasma lipids and plasma antioxidant activity in vivo tests on Wistar rats were weighed cholesterol [11]. Rambutan fruit peels contain flavonoids, tannins and saponins [12]. ...
    Article
    Full-text available
    The present study was carried out to evaluate the in alloxan (150 mg/kgb.wt) induced diabetic rats. The ethanolic extract of Durian (Durio zibethinus Murr.) and rambutan (Nephelium lappaceum L.) fruit peels administered orally to the diabetic rats for 11 days, produced significant decrease in the level of blood glucose. The highest percentage reduction in blood glucose levels were shown of rambutan fruit peels extract with dose 500 mg/kgb.w and the value of persentage reduction were 61.76±4.26%.
  • ... This increase in TAC value is believed to be attributed to the increased activities of GPx (Table 4), CAT (Table 5) and the presence of high phenolic compounds. The lower TAC level seen in rabbits fed high-cholesterol diet and the higher level in rabbits administered phenolic-rich B. angulata juices were in agreement with the previous study by Leontowicz et al. [58]. The investigators showed a significant decrease in antioxidant capacity when Wistar rats were fed high-cholesterol diet compared with those supplemented with polyphenols-and flavonoids-rich durian fruits. ...
    Article
    Full-text available
    Purpose: The consequence of the increased demand due to the population expansion has put tremendous pressure on the natural supply of fruits. Hence, there is an unprecedented growing interest in the exploration of the potentials of underutilized fruits as alternatives to the commercially available fruits. Baccaurea angulata is an underutilized fruit widely distributed in Borneo Island of Malaysia. The present study was conducted to investigate the effects of B. angulata whole fruit (WF), skin (SK) and pulp (PL) juices on malondialdehyde (MDA) levels and antioxidant enzymes in rabbits fed high-cholesterol diet. Methods: Thirty-six male rabbits of New Zealand strain were randomly assigned to six groups. Rabbits were fed either a standard pellet (group NC) or a high-cholesterol diet (groups HC, PC, WF, SK and PL). Groups WF, SK and PL were also given 1 ml/kg/day B. angulata WF, SK and PL juices, respectively. Results: Baccaurea angulata had high antioxidant activities. The administration of the various juices significantly reduced (p < 0.05) the concentration of induced plasma MDA. The decrease in the SOD, GPx, CAT and TAC levels caused by cholesterol feeding was also ameliorated with B. angulata. Conclusion: Our results show that B. angulata fruit is beneficial in positively influencing and managing oxidative damage.
  • ... Durian had reported as an antioxidant and antiproliferative [10]. The content of polyphenols and flavonoids are high enough capable of inhibiting the rise in plasma lipids and plasma antioxidant activity in in vivo tests on Wistar mice burdened cholesterol [11]. Rambutan fruit peel contains flavonoids, tannins and saponins [12]. ...
    Conference Paper
    Full-text available
    Rambutan (Nepheliumlappaceum L.) fruit peel extract had been reported to have very strong antioxidant activity and had more with flavonoids and phenolic compounds. This study aims to determine the potential antidiabetic and antihypercholesterolemia activities of Rambutan fruit peel ethanol extract in vivo. This research design was pre and post-control group, 25 mice were divided into 5 groups. Group I (negative control) were given a solution of 0.5% CMC-Na, group II (positive control antidiabetic) was given Glibenclamide 0.45 mg/kg, III, IV, and V were given ethanol extract of rambutan peel with successive doses of 500, 250, and 125 mg/kgBW. While the antihypercholesterolemic testing, in group II given Cholesteramine 0.8 g/kg, whereas group III, IV and V given ethanol extract of rambutan skin with a dose of 500, 250, and 125 mg/kgBW, respectively. Treatment of mice conducted for 2 weeks. The results showed that the ethanol extract of Rambutan fruit peel with dose of 125, 250, and 500 mg/kgBW had blood glucose lowering activity in mice induced alloxan, the percentage decrease in blood glucose levels at 22.65 ± 2.10%, 49.05 ± 3.22%, 61.76 ± 4.26%. While the antihypercholesterolemia activity of the ethanol extract of Rambutan peel with dose of 125, 250, and 500 mg/kgBW had an activity to lower cholesterol levels 21.39 ± 6.61%, 31.15 ± 18.15%, and 60.75 ± 8.26%, respectively. Keywords— Antihypercholesterolemia, antidiabetic, fruit peel, in vivo, rambutan (Nephelium lappaceum L.)
  • ... Our findings are relevant with the results of endohytes study from pollen pines (Madmony et al. 2005), which revealed Enterobacter cloacae as an IAA-producing bacteria. Durian is a great source of tryptophan (Leontowicz et al. 2011) that can be used as the precursor of IAA biosynthesis by microorganism (Gravel et al. 2007). In tomato, IAA has been reported to have some crosstalk with ethylene during fruits maturation (McAtee et al. 2013). ...
    Article
    Full-text available
    Endophytes are plant-associated microorganisms that able to form colonies in internal tissue and considered as an important component of biodiversity. However, information about the existence of naturally fruits-associated endophytic bacteria at different life-history stages of hosts is very limited. Durian ( Durio zibethinus Murr.) is an exotic tropical fruits with a high economical value, but the occurrence and functional role of associated endophytes remains unexplored. A total of sixteen endophytic bacterial isolates were identified by 16S rRNA sequence analysis from ripe and unripe stages of Durian fruits var. Matahari. These isolates belonged to the genus Staphylococcus, Bacillus, Enterobacter, Moraxella, Gordonia, Salmonella, Rhizobium, Brachybacterium, Kocuria, and Klebsiella. This is the first report of an endophytic bacterial spesies residing in Durian arillus. This research also indicated potency of culturable endophytes from Durian fruits in plant growth promotion.
  • ... The highest ADXC values were found in the additional digestion phase with pancreatic α-amylase, where the highest percentage of total PCs content was released. However, such associated PCs values, compared to those found for EPCs, might be explained by the presence of other bioactive compounds presented in these fruits, such as vitamins and carotenoids (Gayosso-García Sancho et al., 2011;Leontowicz et al., 2011). ...
    Article
    Full-text available
    The presence of dietary fiber (DF) in the food matrix of some tropical fruits plays an important role in the release and absorption of its bioactive compounds, such as phenolic compounds (PCs). The aim of this study was to evaluate the effect of the DF fractions in mango cv. ‘Ataulfo’, papaya cv. ‘Maradol’ and pineapple cv. ‘Esmeralda’, on the bioaccessibility of their PCs and antioxidant capacity (AOXC) under an in vitro digestion model. The highest PCs content and AOXC was found in mango (274.30 mg GAE/100 g FW), followed by papaya (212 mg GAE//100 g FW), and pineapple (107.63 mg GAE/100 g FW), respectively. About 50% of the total PCs in all fruits was released at gastric phase, increasing closer to 60% at intestinal phase in mango and pineapple. However, the highest content of PCs associated to DF was found in mango (2.48 mg GAE/100 g FW) compared with papaya DF fractions (0.96 GAE/100 g FW) and pineapple (0.52 GAE/100 g FW). The presence of DF in mango, papaya and pineapple did not represent a major limitation on the bioaccessibility of its PCs according to the in vitro digestion model used in this study.
  • ... The highest ADXC values were found in the additional digestion phase with pancreatic α-amylase, where the highest percentage of total PCs content was released. However, such associated PCs values, compared to those found for EPCs, might be explained by the presence of other bioactive compounds presented in these fruits, such as vitamins and carotenoids (Gayosso-García Sancho et al., 2011;Leontowicz et al., 2011). ...
    Article
    Full-text available
    The presence of dietary fiber (DF) in the food matrix of some tropical fruits plays an important role in the release and absorption of its bioactive compounds, such as phenolic compounds (PCs). The aim of this study was to evaluate the effect of the DF fractions in mango cv. ‘Ataulfo’, papaya cv. ‘Maradol’ and pineapple cv. ‘Esmeralda’, on the bioaccessibility of their PCs and antioxidant capacity (ADXC) under an in vitro digestion model. The highest PCs content and ADXC was found in mango (274.30 mg GAE/100 g FW), followed by papaya (212 mg GAE//100 g FW), and pineapple (107.63 mg GAE/100 g FW), respectively. About 50% of the total PCs in all fruits was released at gastric phase, increasing closer to 60% at intestinal phase in mango and pineapple. However, the highest content of PCs associated to DF was found in mango (2.48 mg GAE/100 g FW) compared with papaya DF fractions (0.96 GAE/100 g FW) and pineapple (0.52 GAE/100 g FW). The presence of DF in mango, papaya and pineapple did not represent a major limitation on the bioaccessibility of its PCs according to the in vitro digestion model used in this study.
  • ... These bioactive compounds possess high potential to be used as a therapeutic agent. They can be of help to treat patients suffering from diabetes mellitus (help in regulating secretion of insulin) as well as be of use to treat certain cardiovascular diseases (by reducing serum cholesterol) [84,85,[87][88][89][90]. Some of the major bioactive compounds such as anthocyanins, carotenoids, polyphenols, flavonoids, and others are reported to be present in ample amounts in durian fruit. ...
    Article
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    Chronic disease conditions such as diabetes, hypertension, cancer, obesity and oxidative stress continue to be a significant concern among nations of the world, which is threatening the economic and social prosperity of the people. This calls for urgent action among relevant stakeholders to explore productive and sustainable ways of addressing the incidence of these life-threatening health conditions. While medicines have been used in the treatment and management of chronic diseases, its adverse side effects over time leave much to be desired. This calls for a novel and safer approach. Tropical fruits contain a rich repository of bioactive compounds. Reports from several studies in literature indeed showed that bioactive compounds present in tropical fruits are capable of not only addressing the prevalence of chronic disease conditions, but they also have minimal to no known side effect. The broad objective of this journal article is to review the bioactive and health-promoting benefits of tropical fruits in chronic disease prevention and management. The valuable knowledge derived from this review will enable food and pharmaceutical companies to explore the production of novel functional foods/neutraceuticals and potent medicines respectively from tropical fruit sources that can be useful in chronic disease prevention and management.
  • ... The durian leaf and root decoctions show antipyretic (Leontowicz, 2011), febrifugal effects (Brown, 1997) and anti-malarial agent (Bhore et al., 2012), relieve colds; treat phlegm, jaundice, swellings and skin diseases (Bautista et al., 2012). Its fruit is known to have potential medicinal and therapeutic (Chansiripornchai and Pongsamart, 2008), anti-oxidant (Ang et al., 2018), anti-cancer, anticardiovascular, anti-diabetic Siburian et al., 2019) and anti-obesity properties GSJ: Volume 7, Issue 10, October 2019 ISSN 2320-9186 1115 (Leontowicz et al., 2008). ...
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    Durio zibethinus Murr. (Durian) is a medicinal plant that belongs to the family Bombacaceae. In tradition, the decoctions of the leaf and root have believed to show antipyretic effect and can also be used as a febrifuge and anti-malarial agent. In the present study, the concentrations of essential macro and micro elements were determined using Energy Dispersive X-ray Fluorescence techniques (EDXRF) being the most suitable instrument for the multi-element analysis in plant samples. Two macroelements-calcium (Ca) and potassium (K); and seven microelements-iron (Fe),manganese (Mn),zinc (Zn),copper (Cu), rubidium (Rb), strontium (Sr) and bromine (Br) were analyzed in different parts (leaves, stem-bark and roots) of Durio zibethinus Murr. The results revealed the levels of the two macroelements and seven microelements in Durio zibethinus leaves, stem-bark and roots. The levels of elements in different plant parts were found not to be significantly different (p < 0.05). This study is based on the elemental concentration in different parts of studied plant and their biological roles on human physiology. And the findings show that the plant contains important elements for human metabolism and prevention or healing of diseases.
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    The rind of rambutan fruit (Nephelium lappaceum L.) has been reported to have a very strong antioxidant activity with IC50 value of 7.74 µg / mL. The fruit contains  avonoids and phenolic. This compounds are potentially as hypolipidemic effect. This study aims to determine the hypolipidemic effect of 96% of ethanolic extract of rind of rambutan fruit in wistar strain male rats. This research method is the pre-and post-control group design. 25 rats were divided into 5 groups. Group I (negative control) were treated by a solution of 0.5% CMC-Na, group II (positive control) were treatedby cholestyramine 0.8 kg / kg, whereas group III, IV and V treated by 96% of ethanolic extract of rind of rambutan with a dose of 125 , 250, and 500 mg / kg respectively. hiperkolesterlemia induction is done by giving a high cholesterol diet and feed for 4 weeks. High-cholesterol diet consists of cooking oil, quail egg yolk, water, PTU and feed high cholesterol consisting of margarine and standard feed. Treatment of mice was conducted for 2 weeks. The results showed that the 96% of ethanolic extract of rind of rambutan fruit with a dose of 125, 250, and 500 mg / kgbw have antihyperkolesterol activity 21.39 ± 6.61%, 31.15 ± 18.15%, and 60.75 ± 8, 26%.
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    This research study aimed to explore the antidiabetic and antihypercholesterolemia activities of rambutan (Nephelium lappaceum L.) and durian (Durio zibethinus Murr.) fruit peels extracts. Diabetic rats induced by alloxan intra-peritoneal at dose 150 mg/kg.bw. Rats divided into eight groups, negative control received 0.5% CMC-Na, Glibenclamide 0.45 mg/kg.bw (positive control), groups of III, IV, and V were given ethanolic extracts of durian rind with successive doses of 500, 250, 125 mg/kg.bw, while groups of VI, VII and VIII were given of rambutan peels extracts for 11 days. Whereas, antihypercholesterolemia activity, high cholesterol gained by high-fat fed diet for 28 days and treated with the extracts for 14 days. The highest percentage reduction in blood glucose and cholesterol levels were shown of rambutan fruit peels extract with dose 500 mg/kg.bw and the value of percentage reduction were 61.76±4.26% and 60.75±8.26%, respectively which the activity were higher than positive control. While the durian rind extract with dose 500 mg/kg.bw had showed the reduction glucose levels at 50.19±3.66% and 35.82 ± 5.00% for reduction cholesterol levels. Nephelium lappaceum and Durio zibethinus peels extracts had the antidiabetic and antihypercholesterolemia activities at doses of 125 to 500 mg/kg.bw.
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    p>Objective: Chinese mitten crab is a famous aquatic species in eastern Asian region, but their edible parts, particularly hepatopancreas and gonads, generally contain very high levels of lipids that may have negative effects on human health. This study investigated the effects of different edible parts of Chinese mitten crab on the body weight and lip metabolism for Kunming mice. Method: The mice were fed with diets containing one part of an Chinese mitten crab or the mixture of parts of an Chinese mitten crab for 4 weeks. There were 9 treatments. The triacylglycerol (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were enzymatically determined using commercial kits (purchased from Nanjing Jiancheng Bioengineering Institute, China). The arteriosclerosis index (AI) was calculated by the equation: AI = (TC – HDL-C)/HDL-C. The levels of fatty acid syntheses (FAS), the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMG-CoA) and lipoprotein lipase (LPL) were measured using commercially available kits according to the manufacturer’s instructions. The significant differences between the groups were further analyzed by Bonferronis’s t-test. Results: Our results showed that the crab hepatopancreas, gonads and the mixed male crab-edible parts increased blood lipids in some experiment group of mice corresponding to a change in the nutrition-related liver enzymes. It shows that addition of the Chinese mitten crab has an adverse effect on the blood lipid levels in mice. The FFH, FFMI and FMMI groups had significantly higher weight than the FN group (P < 0.05). The crab hepatopancreas, crab gonads and the mixed male crab-edible parts cause an increase in the blood lipid levels. The crab mixture significantly affected the AI value of male and female mice (P < 0.01). The level of FMMI group was significantly higher than the FN group (P < 0.05). Other groups showed no significant difference. The level of the FFMI group was significantly lower than the FN group (P < 0.05), and levels in the MMM and MFMI groups were significantly lower than the MN group (P < 0.05). Conclusion: It clearly showed that long-term feeding with the Chinese mitten crab has an adverse effect on the blood lipid levels in mice. One the one hand, the weight, liver index and fat index of experimental mice were changed than normal mice. On the other hand, the crab diet affects the level of TC, TG, AI and FASN on increasing. It is suggested that the special diet has affected lip metabolic alteration associated with contents of serum lipids and metabolic enzymes. But according to a certain regular feeding, there would be no adverse effect on mice. On the contrary, it may adjust the blood lipid in mice </p
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    Durian (Durio zibethinus Murr) and longan (Euphoria longan Lamk) fruit peels contain flavonoid compounds that might have potential activity as antihypercholesterol. The purpose of this study to determine the antihypercholesterol effect of ethanol extract of durian and longan fruit peels on the white rats Wistar strain. The research method is the pre and post control group design. Fourty rats were divided to 8 treatment groups. Group I (negative control) were given CMC-Na 0,5%, group II (positive control) were given Colestiramine 0,8 g/kgBW, group III, IV, V, VI, VII and VIII treated by ethanol extract of durian and longan fruit peels with consecutive doses 125, 250, and 500 mg/kgBW. Before treatment, the rats were given high cholesterol diets and fed diets supplemented with cholesterol during 4 weeks. The composition of high cholesterol diets were cooking oil, quail egg yolk, water, PTU (Propyltiourasil) and fed diets supplemented with cholesterol were margarine, quail egg yolk, standard feed. The treatment of antihypercholesterol testing on the rats conducted for 2 weeks. The result showed that durian and longan fruit peels ethanol extracts have potential antihypercholesterol activity. Percentage decreasing of cholesterol total level of ethanol extract of durian and longan fruit peels with consecutive doses 150, 250, and 500 mg/kgBW were 12. respectively. While Colestiramine 0.8 g/kgBW as a positive control had value decreasing percentage of total cholesterol was 34.20%.
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    During the recent years, microarray analysis of gene expression has become an inevitable tool for exploring toxicity of drugs and other chemicals on biological systems. Therefore, toxicogenomics is considered as a fruitful area for searching cellular pathways and mechanisms including cancer, immunological diseases, environmental responses, gene-gene interactions and chemical toxicity. In this work, we examined toxic effects of Tungsten Borides NPs on gene expression profiling of the human lung alveolar epithelial cells (HPAEpiC). In line with this purpose, a single crystal of tungsten boride (mixture of WB and W2B) nanoparticles was synthesized by means of zone melting method, and characterized via using X-ray crystallography (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. Cell viability and cytotoxicity were determined by 3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT), neutral red (NR) and lactate dehydrogenase (LDH) release tests. The whole genome microarray expression analysis was performed to find out the effects of WB and W2B NPs mixture on gene expression of the HPAEpiC cell culture. 123 of 40,000 gene probes were assigned to characterize expression profile for WB/W2B NPs exposure. According to results; 70 genes were up-regulated and 53 genes were down-regulated (≥2 fold change). For further investigations, these genes were functionally classified by using DAVID (The Database for Annotation, Visualization and Integrated Discovery) with gene ontology (GO) analysis. In the light of the data gained from this study, it could be concluded that the mixture of WB/W2B NPs can affect cytokine/chemokine metabolism, angiogenesis and prevent migration/invasion by activating various genes.
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    Characteristics of the spine of ‘Monthong’ durian such as color of the tip have been known to be an indicator of fruit maturity. Visible spectroscopy of the spine of durian was investigated for classification of maturity. Partial least squares discriminant analysis was performed to model the classification. The model using absorbance spectra transformed by the standard normal variate achieved the best accuracy of classification (94.7%) into four maturity classes ranging from 113 to 134 days after anthesis. The classification was attributable to the absorbance of chlorophyll a, carotenoids and anthocyanins in the spine.
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    Tropical fruits represent one of the most important crops in the world. The continuously growing global market for the main tropical fruits is currently estimated at 84 million tons, of which approximately half is lost or wasted throughout the whole processing chain. Developing novel processes for the conversion of these by-products into value-added products could provide a viable way to manage this waste problem, aiming at the same time to create a sustainable economic growth within a bio-economy perspective. Given the ever-increasing concern about sustainability, complete valorization through a bio-refinery approach, i.e. zero waste concept, as well as the use of green techniques is therefore of utmost importance. This paper aims to report the status on the valorization of tropical fruit by-products within a bio-refinery frame, via the application of traditional methodologies, and with specific attention to the extraction of phenolics and carotenoids as bioactive compounds. The different types of by-products, and their content of bioactives is reviewed, with a special emphasis on the lesser-known tropical fruits. Moreover, the bioactivity of the different types of extracts and their possible application as a resource for different sectors (food, pharmaceutical and environmental sciences) is discussed. Consequently, this review presents the concepts of tropical fruit biorefineries, and the potential applications of the isolated fractions.
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    Medicinal plants are sources of important therapeutic aids for alleviating human ailments. Medicinal herbs are known to contain a variety of antioxidants. Herbal medicine is the use of medicinal plants for the prevention and treatment of diseases, it ranges from traditional and popular medicines of every country to the use of standardized herbal extracts. In tune with this effort, the objective set for the present study is to identify the phytochemical constituents of the leaves of Rhinacanthus nasutus in order to understand the nature of the principle component responsible for its medicinal property. A preliminary absorbance survey scan of the methanolic extract of R. nasutus evidenced the presence of multiple components in the extract. Two peaks observed in the HPLC spectrum showed the presence of two compounds in the extract. GCMS profile revealed that the active components present in the leaf extract might be alkaloids or polyphenols. The results of IR spectrum revealed that band 1 possess compounds of polyphenolic nature and band 2 possesses compounds that are having a hydroxyl and a carbonyl groups. Some more studies need to be conducted to confirm the presence of bioactive component responsible for its therapeutic value.
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    Two new polyphenolic compounds named retusaphenol [2-hydroxy-4-methoxy-1,3-phenylene-bis- (4- hydroxy-benzoate)] and (+)-retusa afzelechin [afzelechin - (4��8) - afzelechin - (4��8) - afzelechin] together with ten known compounds: luteolin, (+) - afzelechin, (+) - catechin , vitexin , �-sitosterol acetate, �-amyrin acetate, moretenone, friedelenol, �-amyrin and �-sitosterol were isolated for the first time from the ethanolic extract of the aerial parts of Ficus retusa L. “variegata”. Their chemical structures were established on basis of spectral evidence; UV, IR, MS, 1H- and 13C-NMR as well as comparison with literature values. Anticancer (IC50 68.64 μg/ml against Hep G2 cells and >100 μg/ml aganist HCT-116 cells), antioxidant (SC50 0.85 μg/ml), antidiabetic, hepatoprotective, anti-inflammatory and antimicrobial activities of the different plant extracts were also studied and significant results were obtained.
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    Antioxidant activities, total polyphenols and flavonoids, and antimicrobial effects in some plant pigments were determined in order to use these natural materials for cosmetics. The DPPH (1,1-diphenyl-2-picryl hydrazyl radical scavenging activity, % of control at maximum plants extract concentrations of 2500 mg/L) in the thirteen natural plant pigments (black rice, purple sweet potato, yellow bitter melon, yellow paprika, red cabbage, yellow gardenia, blue gardenia, Chinese foxglove, mulberry leave, onion peel, grape peel, mulberry and red beet) ranged from 88.9% for red cabbage to 18.0% for blue gardenia. The highest total polyphenol content (404.2 μg/ml) was measured in the onion peel pigment, and the lowest was in Chinese foxglove pigment (11.4 μg/ml). The red cabbage had the highest total flavonoid amount which was 95.5 μg/ml. The antimicrobial activities of the natural plant pigments were evaluated using the agar diffusion method. Most of the natural pigments for Bacillus subtilis, Micrococcus luteus, Escherichia coli, and Vibrio parahaemolyticus showed the clear zone formation of growth inhibition. Purple sweet potato, mulberry, mulberry leaf, grape peel, and blue gardenia showed high antimicrobial activities. These findings suggest that the pigments derived from natural plants had high biological activities, and exhibited different properties depending on each kind of pigments. Therefore these plant resources, having active functional components, can be used as excellent materials for natural cosmetics and food supplements.
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    There are a few investigations on Indigo (Polygonum tinctorium Ait.), as a medicinal plant. Therefore, the aim of this study was to assess the contents of bioactive compounds, antioxidant and antiproliferative activities and to compare with another medicinal plant Prolipid. It was found that the bioactive compounds from different parts of Indigo water extracts varied (P < 0.05): polyphenols and flavonoids were significantly higher in Prolipid, flavanols in Indigo seeds, and vitamin C similar in Indigo leaves and Prolipid. The antioxidant activity by ABTS, FRAP, CUPRAC and DPPH assays was significantly different (P < 0.05): the highest in Prolipid, following by Indigo mature leaves. DPPH kinetic measurements compared, distinguished and discriminated the antiradical activity among Indigo and Prolipid water extracts by multivariate analysis. The interaction between polyphenol extracts of Indigo mature leaves and BSA showed that Indigo has a strong ability, as other medicinal plants, to quench the intrinsic fluorescence of BSA by forming complexes. In conclusion, for the first time Indigo mature leaves were analyzed and compared with widely consumed Prolipid. The relatively high content of bioactive compounds, positive antioxidant, fluorescence and antiproliferative properties of Indigo justify the use of this plant as a new source of valuable antioxidants.
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    Polyphenolic compounds are abundantly found in natural dyes. The cupric reducing antioxidant capacity assay originally developed in our laboratories was utilized to estimate the total polyphenolic content of natural dyes (i.e., Rubia tinctorum L., Curcuma longa L., Alkanna tinctoria, Matricaria chamomilla, Dactylopius coccus Costa) for the first time. The polyphenolic compounds such as ellagic acid, gallic acid, quercetin, rutin, fisetin, myricetin, kaempferol, luteolin, apigenin, and morin were all capable of reducing the Cu(II)–neocuproine reagent to the Cu(I)–neocuproine chelate showing maximum absorbance at 450nm, and the responses of synthetic mixture components were additive in accordance with Beer's law. As a comparative reference method, the AlCl3/potassium acetate spectrophotometric method was applied to total flavonoid assay of these dyes. The results of the proposed and reference methods were correlated with high performance liquid chromatography (HPLC) findings expressed in the units of quercetin (QR) equivalent polyphenolic concentration. The individual phenolic constituents of dye extracts were identified and quantified by HPLC on a C18 column (alizarin, curcumin, carminic acid, etc.). The method of standard additions was applied to the solutions of these dyes by adding standard increments of QR and measuring the resulting absorbances.
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    The interaction between three kinds of flavonoids and bovine serum albumin (BSA) was investigated by fluorescence and UV–vis absorption spectrometry. The results indicated that flavonoids have strong ability to quench the intrinsic fluorescence of BSA by forming complexes. The binding constants, number of binding sites, thermodynamic parameters and energy transfer mechanisms were also investigated. Conformation change of BSA was observed from synchronous, three-dimensional fluorescence and circular dichroism spectrum.
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    The effect of consumption of red palm oil and refined palm olein diets on hematological parameters and histopathology of liver was studied in animals. Four-week- old rats (n = 8 per group) were fed for 28 days on standard, dry rat food supplemented (10% and 20% by weight) with red palm oil (RPO), refined palm olein (REFPO) and corn oil (CO). Final body weights of rats fed control and 10% oil- containing diets were superior (p < 0.05) to those of the dietary groups fed 20% oil- containing diets. Organ weight studies showed that all organs in the 10% oil-fed animals were heavier and larger when compared with those of other experimental animals. There were reductions in organ sizes following increases in the oil contents of the diets from 10% to 20%, as were the reductions in apparent protein absorption of 20% oil-fed rats when compared with 10% oil-fed rats. Hematological examination of rats did not reveal any statistically significant variations in the numbers of total WBC, platelets, amounts of Hb or levels of haematocrit between the test groups and the control (p > 0.01). The plasma glucose concentrations were consistent with reference values for rats. Urea, total protein .and total bilirubin concentrations did not differ significantly (p > 0.05) among the experimental groups throughout the duration of the experiment. The total cholesterol values increased with increasing levels of oil beyond the 10% inclusion level. The total cholesterol concentrations of rats fed CO-based diets were similar to those fed palm oil - containing diets, as were those of REFPO-fed rats when compared with RPO-fed rats. Organopathological examination revealed no differences in cellular architecture of the liver of animals fed diets containing 10% oil. The reduction in cell size and distortion of radial architecture in livers of animals fed 20% oil diets were mild. The findings demonstrated that consumption of palm oil at 10% level impacts positively on protein absorption, growth / development of tissues, blood parameters and tissue histology. Up to 20% palm oil can be included in rat diets without adverse effects on hematological parameters and liver histology.
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    ETHNOPHARMACOLOGICAL RELEVANCE: Acalypha indica, Cassia alata, Lawsonia inermis, Punica granatum, Thespesia populnea and Wrightia tinctoria are folklore medicines extensively used in the treatment of ringworm infections and skin related diseases in Tamil Nadu, India. AIM: The present study was designed to investigate the in vitro antifungal activity of certain medicinal plants and the pure compound indirubin isolated from Wrightia tinctoria. MATERIALS AND METHODS: The hexane, chloroform, methanol and ethanol extracts of six different plants were investigated against dermatophytes, non-dermatophytes and yeasts. Chloroform extract of Wrightia tinctoria leaf was fractionated using column chromatography and the major compound was identified using spectroscopic techniques. Antifungal activity was studied by spore germination test using agar dilution method. The minimum inhibitory concentration (MIC) was determined using broth microdilution method. RESULTS: Wrightia tinctoria showed promising activity against dermatophytic and non-dermatophytic fungi. Leaf chloroform extract showed activity at 0.5 mg/ml against Trichophyton rubrum, Epidermophyton floccosum, Aspergillus niger and Scopulariopsis brevicaulis. The major compound, identified as indirubin, exhibited activity against dermatophytes such as Epidermophyton floccosum (MIC=6.25 μg/ml); Trichophyton rubrum and Trichophyton tonsurans (MIC=25 μg/ml); Trichophyton mentagrophytes and Trichophyton simii (MIC=50 μg/ml). It was also active against non-dermatophytes (Aspergillus niger, Candida albicans and Cryptococcus sp.) within a MIC range of 0.75-25 μg/ml. CONCLUSION: The indole compound indirubin from Wrightia tinctoria showed antifungal activity and may be useful in the treatment of dermatophytosis.
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    The pH effects on the secondary structures of egg albumin were investigated using Fourier transform infrared-attenuated total reflection (FTIR-ATR) technique with a single-bounce diamond crystal. The albumin was first denatured in a series of solutions with pH ranging from 1 to 12. The albumin film was then cast on the ATR crystal from the albumin solution for the IR spectrum collection. Significant secondary structure spectral differences were observed for these films. The findings are presented in terms of the shape and position of the albumin amide I band between 1600 and 1700 cm(-1).
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    This research work was carried out to quantify the total phenolics, flavonoids, carotenoides and vitamin C contents, reported as antioxidants, in the extracts of four locally available varieties of durian. Fruit was extracted using dichloromethane: pentane (1:1 v/v) and subjected to study the various quality parameters. The total phenolic contents from durian fruit extract were found in the range of 690.62-998.29 mg/L, showing the significant inter-varietals variations. The total flavonoids and vitamin C contents from fruit extract were found in the range of 211.36-220.34 and 18.87-25.1 mg/L, respectively. Whereas, the total carotenoides contents of fruit extract were found in a low concentrations i.e. 0.05-0.08 mg/L. The statistical analysis showed significant (p < 0.05) variations in the total phenolic, carotenoides and vitamin C contents while non-significant (p > 0.05) variation in total flavonoids contents among different varieties of durian. Caffeic acid and quercetin were the dominant antioxidant substances found in durian. In conclusion, the bioactivity of ripe durian was high and the total polyphenols were the main contributors to the overall antioxidant capacity. INTRODUCTION Most of the phytochemicals are an integral
  • Article
    Publisher Summary This chapter discusses the analysis of total phenols and other oxidation substrates and antioxidants by means of Folin-Ciocalteu reagent. Analyses of the Folin-Ciocalteu (FC) type are convenient, simple, and require only common equipment and have produced a large body of comparable data. Under proper conditions, the assay is inclusive of monophenols and gives predictable reactions with the types of phenols found in nature. Because different phenols react to different degrees, expression of the results as a single number—such as milligrams per liter gallic acid equivalence—is necessarily arbitrary. Because the reaction is independent, quantitative, and predictable, analysis of a mixture of phenols can be recalculated in terms of any other standard. The assay measures all compounds readily oxidizable under the reaction conditions and its very inclusiveness allows certain substances to also react that are either not phenols or seldom thought of as phenols (e.g., proteins). Judicious use of the assay—with consideration of potential interferences in particular samples and prior study if necessary—can lead to very informative results. Aggregate analysis of this type is an important supplement to and often more informative than reems of data difficult to summarize from various techniques, such as high-performance liquid chromatography (HPLC) that separate a large number of individual compounds .The predictable reaction of components in a mixture makes it possible to determine a single reactant by other means and to calculate its contribution to the total FC phenol content. Relative insensitivity of the FC analysis to many adsorbents and precipitants makes differential assay—before and after several different treatments—informative.
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    The main objective of this review was to describe the physicochemical and nutritional characteristics of twenty selected exotic fruits and the influence of their physiologically active compounds on human health, through scientifically proven information. The review presents the biologically active metabolites derived from exotic fruits (polyphenols, flavonoids, flavanols, tannins, ascorbic acid, anthocyanins, volatile compounds, minerals, and organic acids) and various analytical methods for their detection (elemental analysis, electrophoretic separation by SDS-polyacrylamide gel electrophoresis, and fast protein liquid and ion-exchange chromatography; GC-MS, HPLC/diode array detection (DAD), circular dichroism (CD), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR), ultraviolet spectroscopy, two- and three-dimensional fluorimetry (2D-FL) and (3D-FL), and antioxidant radical scavenging assays (DPPH, FRAP, CUPRAC, ABTS, and ORAC). The correlation between the polyphenols and other bioactive compounds, and their antioxidant activities was reported for different fruit extracts. During the last two decades our international scientific group investigated in vitro the physicochemical and nutritional characteristics of avocado, dragon fruit, durian, kiwifruit, mango, mangosteen, persimmon and snake fruit, and in vivo their influence on laboratory animals and humans. Supplementation of diets with exotic fruits positively affects plasma lipid profile, antioxidant activity and histological examination of aorta in rats fed cholesterol-containing diets.
  • Article
    The aim of this research was to investigate the bioactivity of durian, snake fruit and mangosteen, rare exotic Thai fruits. These fruits were compared among them and with conventional fruits: durian with mango and avocado, and snake fruit with mangosteen and kiwifruit in order to find the preferable diet for human consumption. The contents of polyphenols, flavonoids, flavanols, tannins, anthocyanins, ascorbic acid and carotenoids, and the level of antioxidant potential by ABTS, DPPH, FRAP and CUPRAC in different extracts (methanol, water, acetone, and hexane) were determined. The presence of polyphenols (flavonoids and phenolic acids) in the investigated samples was characterized by Fourier transform infrared (FT-IR) spectroscopy and three-dimensional fluorimetry (3D-FL).The in vivo studies were carried out on 25 male Wistar rats, divided into 5 diet groups, each of 5. During 30 days of the experiment the rats of all 5 groups were fed basal diet (BD), which included wheat starch, casein, soybean oil, vitamin and mineral mixtures. The rats of the Control group were fed only the BD. The BD of the other 4 groups was supplemented with 1% of nonoxidized cholesterol (NOC) (Chol group), 1% of NOC in each group and 5% of lyophilized fruits: durian (Chol/Durian), snake fruit (Chol/Snake), mangosteen (Chol/Mangosteen). After the experiment diets supplemented with exotic fruits significantly hindered the rise in plasma lipids and hindered the decrease in the plasma antioxidant activity. In conclusion, the contents of bioactive compounds and the antioxidant potential are relatively high in the studied fruits and varied among them depending on the extraction procedure. FT-IR and 3D-FL can be used as additional tools for identification and comparison of bioactive compounds. Supplementation of diets with exotic fruits positively affects plasma lipid profile and antioxidant activity in rats fed cholesterol-containing diets.
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    The flowers of Stachys lavandulifolia Vahl (Lamiaceae) and Malva sylvestris Linn (Malvaceae) are traditionally used to treat various skin disorders, antimicrobial and anti-inflammatory. The chloroform extract of M. sylvestris flowers and aqueous extract of S. lavandulifolia flowers were used to evaluate the wound healing activity at 200 mg/kg/day dose. Wounds were induced in Wistar rats divided into four groups as following; Group-I was treated with cold cream. Groups-II and -III were treated with cold cream containing of extracts, Group-IV received the standard drug (nitrofurazone). The efficacy of treatment was evaluated based on wound area and histopathological characteristics. The extract-treated animals by M. sylvestris showed significant reduction in the wound area when compared with other groups. Also, histopathological studies of the tissue obtained on days 6 th , 9 th and 16 th from the extract-treated by M. sylvestris showed increased well organized bands of collagen, more fibroblasts and few inflammatory cells.
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    An account on the reinvestigation of the old dye and medicinal plant Isatis tinctoria as an anti-inflammatory and current research on the active principles in woad is given. In a broad-based screening, a dichloromethane extract from the leaves displayed significant activities on several clinically relevant targets of inflammation. The cyclooxygenase-2 inhibitory principle was identified with the aid of HPLC-based activity profiling as the alkaloid tryptanthrin. In cell based assays, tryptanthrin strongly inhibited eicosanoid synthesis catalyzed by cyclooxygenase-2 and 5-lipoxygenase. A supercritical carbon dioxide extraction process was developed to replace the dichloromethane extract. Dichloromethane and carbon dioxide extracts showed in vivo anti-inflammatory activity in topical and oral application. With the aid of electrospray ionization liquid chromatography-mass spectrometry coupled skin microdialysis, tryptanthrin was found to penetrate the skin. The penetration from the extract was better than for the pure alkaloid. A screening of 67 woad samples of different geographic origin revealed up to 30-fold differences in tryptanthrin content in leaves.
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    Seeds and leaves of indigo (Polygonum tinctorium Ait.) plant were investigated and compared with another medicinal plant named prolipid for their properties such as chemical composition, antioxidant, and anticancer effects by Fourier transform infrared, three-dimensional fluorescence spectroscopy, and electrospray ionization-MS in negative mode. It was found that polyphenols, flavonoids, and flavanols were significantly higher in prolipid (P<0.05), following by indigo mature leaves, immature leaves, and seeds. Methanol extract of mature indigo leaves in comparison with the ethyl acetate extract showed higher inhibition of proliferation. The interaction between polyphenol extracts of indigo mature leaves and BSA showed that indigo has a strong ability, as other widely used medicinal plants, to quench the intrinsic fluorescence of BSA by forming complexes. In conclusion, indigo mature leaves were compared with prolipid. High content of bioactive compounds, antioxidant, fluorescence, and antiproliferative properties of indigo justifies the use of this plant as a medicinal plant and a new source of antioxidants.
  • Article
    The antiradical activities of various antioxidants were determined using the free radical, 2,2-Diphenyl-1-picrylhydrazyl (DPPH*). In its radical form. DPPH* has an absorption band at 515 nm which dissappears upon reduction by an antiradical compound. Twenty compounds were reacted with the DPPH* and shown to follow one of three possible reaction kinetic types. Ascorbic acid, isoascorbic acid and isoeugenol reacted quickly with the DPPH* reaching a steady state immediately. Rosmarinic acid and δ-tocopherol reacted a little slower and reached a steady state within 30 min. The remaining compounds reacted more progressively with the DPPH* reaching a steady state from 1 to 6 h. Caffeic acid, gentisic acid and gallic acid showed the highest antiradical activities with a stoichiometry of 4 to 6 reduced DPPH* molecules per molecule of antioxidant. Vanillin, phenol, γ-resorcylic acid and vanillic acid were found to be poor antiradical compounds. The stoichiometry for the other 13 phenolic compounds varied from one to three reduced DPPH* molecules per molecule of antioxidant. Possible mechanisms are proposed to explain the experimental results.
  • Article
    The aim of this study is to investigate the influence of certain factors on the yield, antioxidant activity (AA) and total phenolic content (TPC) of guava leaf extract. The effects of pretreatment of leaf sample prior to extract, extraction method, and the leaf age were investigated. Folin–Ciocalteau was used to determine the TPC. Trolox equivalent antioxidant capacity (TEAC) and equilibrium concentration (EC) were used for evaluation of AA. Results indicated that ultrasonication is the most suitable method for guava leaf extraction as it yielded the extract with the significantly highest TPC and AA. Blanching followed by ice water cooling (BCD) was suggested for the pretreatment process of guava leaves. The study of leaf maturity demonstrated that the highest activity was from the young leaves. Hot water was the best solvent to extract the active principles. The extract of BCD pretreated young leaves, extracted by hot water exhibited the highest TPC and AA with the TEAC and EC values of 24.30 ± 0.50 and 20.41 ± 0.67 mM/mg, respectively. These values are 1.88 and 8.72 times higher than the synthetic antioxidant butylated hydroxy toluene (BHT) and 1.75 and 1.21 times higher than vitamin E, respectively. It was concluded that pretreatment and drying process, method of extraction and leaf maturity played important roles on the bioactive compounds and their antioxidant power of guava leaf extract.
  • Article
    The physicochemical (pH, soluble solids, titratable acidity, sugars and organic acids), flavour and sensory properties of five Malaysian durian cultivars (D2, D24, MDUR78, D101 and Chuk) were studied. There were significant differences (P < 0.05) among the five cultivars in terms of all physicochemical characteristics tested with the exception for D2 and MDUR 78, which had similar physicochemical characteristics. Twenty two esters, 14 sulphur compounds, 7 alcohols, 3 aldehydes and 1 ketone were detected in the durian pulp of the five different cultivars using solid-phase microextraction coupled to gas chromatography-time of flight mass spectrometry. Diethyl disulphide, ethyl-n-propyl disulphide, diethyl trisulphide and ethanethiol were the predominant sulphur-containing compounds in all the cultivars. The major esters present in durian were either ethyl propanoate, ethyl-2-methyl butanoate, or propyl-2-methylbutanoate and their levels varied within cultivars. Principal component analysis applied to the data differentiated all cultivars based on 29 volatile flavour compounds exhibiting significant differences (P < 0.05) between cultivars. Principal components 1 and 2 explained 89% of the total variance. A strong correlation was observed between sensory properties with flavour compound and physicochemical characteristics of the fruit.
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    Full-text available
    Aqueous extract, proanthocyanidin rich extract, and organic extracts of Cymbopogon schoenanthus L. Spreng (lemon grass) shoots from three different locations in South Tunisia were screened for their antioxidant, acetylcholinesterase and antimicrobial activities. In addition to the evaluation of these activities, the contents of flavonoids and total phenolic compounds were determined.Antioxidant activity measured by DPPH assay showed that the proanthocyanidin extract exhibited higher antioxidant activity than the aqueous extract. Extract concentration providing 50% inhibition (IC50) ranged from 16.4 ± 6.8 μg/mL to 26.4 ± 6.8 μg/mL. The antioxidant activity was also determined using the β-carotene/linoleic acid bleaching test. The best results (IC50 = 0.11 ± 0.10 mg/mL) were obtained with the proanthocyanidin extract of the plants collected from the desert region (Dhibat).The greatest acetylcholinesterase inhibitory activity (IC50 = 0.23 ± 0.04 mg/mL) was exhibited by the ethyl acetate and methanol extracts of the plants collected from the mountainous region. It seems that extracts obtained with more polar solvents gave better results.The proanthocyanidin extracts showed a good antimicrobial activity against Streptococcus sobrinus at low concentration (MIC = 4 mg/mL). Therefore, these extracts could be used to prevent carious lesions by inhibiting S. sobrinus growth.
  • Article
    The aim of this investigation was to compare the bioactive and nutrient compounds, fatty acids, and antioxidant and antiproliferative activities of Mon Thong durian at different stages of ripening. It was found that the total polyphenols, flavonoids, flavanols, ascorbic acid, tannins and the antioxidant activity determined by four assays (CUPRAC, DPPH, ABTS and FRAP) differed in immature, mature, ripe and overripe samples. The content of polyphenols and antioxidant activity were the highest in overripe durian, flavonoids were the highest in ripe durian, and flavanols and antiproliferative activity were the highest in mature durian (p < 0.05). FTIR spectra of polyphenols, HPLC profiles of fatty acids, the antioxidant and antiproliferative activities can be used as indicators to characterise different stages of durian ripening.
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    Farnesoid X receptor (FXR) is a ligand-activated nuclear receptor and serves as a key regulator to maintain health of the liver and intestine. Bile acids are endogenous ligands of FXR, and there are increasing efforts to identify FXR modulators to serve as biological probes and/or pharmaceutical agents. Natural FXR ligands isolated from plants may serve as models to synthesize novel FXR modulators. In this study, we demonstrated that epigallocatechin-3-gallate (EGCG), a major tea catechin, specifically and dose-dependently activates FXR. In addition, EGCG induced FXR target gene expression in vitro. Surprisingly, in a co-activator (SRC2) recruitment assay, we found that EGCG does not recruit SRC2 to FXR, but it dose-dependently inhibits recruitment of SRC2 to FXR (IC(50), 1μM) by GW6064, which is a potent FXR synthetic ligand. In addition, EGCG suppressed FXR target gene expression induced by either GW4064 or chenodeoxycholic acid in vitro. Furthermore, wild-type and FXR knockout mice treated with an acute dose of EGCG had induced mRNA expression in a subset of FXR target genes in the intestine but not in the liver. In conclusion, EGCG is a unique modulator of FXR in the intestine and may serve as an important model for future development of FXR modulators.
  • Article
    Hexavalent chromium [Cr(VI)] is a human carcinogen that results in the generation of reactive oxygen species (ROS) and a variety of DNA lesions leading to cell death. Epigallocatechin-3-gallate (EGCG), the major polyphenol present in green tea, possesses potent antioxidative activity capable of protecting normal cells from various stimuli-induced oxidative stress and cell death. Here we demonstrated that co-treatment with EGCG protected human normal bronchial epithelial BEAS-2B cells from Cr(VI)-induced cell death in a dose-dependent manner. Cr(VI) induces apoptosis as the primary mode of cell death. Co-treatment of BEAS-2B cells with EGCG dose-dependently suppressed Cr(VI)-induced apoptosis. Fluorescence microscopic analyses and quantitative measurement revealed that EGCG significantly decreased intracellular levels of ROS induced by Cr(VI) exposure. Using a well-established K(+)/SDS precipitation assay, we further showed that EGCG was able to dose-dependently reduce DNA-protein cross-links (DPC), lesions that could be partially attributed to Cr(VI)-induced oxidative stress. Finally, analyses of Affymetrix microarray containing 28,869 well-annotated genes revealed that, among the 3412 genes changed more than 1.5-fold by Cr(VI) treatment, changes of 2404 genes (70%) were inhibited by pretreatment of EGCG. Real-time PCR confirmed the induction of 3 genes involved in cell death and apoptosis by Cr(VI), which was eliminated by EGCG. In contrast, Cr(VI) reduced the expression of 3 genes related to cellular defense, and this reduction was inhibited by EGCG. Our results indicate that EGCG protects BEAS-2B cells from Cr(VI)-induced cytotoxicity presumably by scavenging ROS and modulating a subset of genes. EGCG, therefore, might serve as a potential chemopreventive agent against Cr(VI) carcinogenesis.
  • Article
    Methanol extracts from the leaves, bark and roots of four Cameroonian medicinal plants, Bersama engleriana, Cupressus lusitanica, Vitellaria paradoxa and Guibourtia tessmannii were tested for their in vitro cytotoxicity, antigonorrheal and antireverse transcriptase activities. The XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide inner salt) assay, the dilution method and reverse transcriptase (RT) assay were used for the investigations. Preliminary phytochemical analysis of the extracts was also conducted using standard methods. Results showed that all extracts contained compounds belonging to the classes of phenols and terpenoids. They were also able to reduce in dose dependent manner, the proliferation of the cancer THP-1, DU145, HeLa, MCF-7, HepG2 and the normal Vero cells. IC(50) values below 30μg/ml were noted with extract from the three parts of B. engleriana on at least two of the five studied cancer cell lines, the lowest value of 5.9μg/ml being obtained with sample from the bark. IC(50) values below 30μg/ml were also recorded with extracts from the leaves (on HeLa cells) and bark (on MCF-7) of G. tessmanii, and that from the bark of C. lusitanica on MCF-7. Extracts from B. engleriana and those from the bark of V. paradoxa gave the minimal inhibitory concentrations (MIC) values below 100μg/ml on most of the 10 tested Nesseria gonorrhoeae strains. Extracts from B. engleriana also inhibited more than 80% the activity of the Human Immuno-deficiency Virus (HIV) enzyme. Finally, the results of the present study provide baseline information for the use of B. engleriana, C. lusitanica, G. tessmanii, V. paradoxa.
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    Full-text available
    In the field of cosmetic dyes, used for coloring the hair and skin, there is a clear tendency to replace the widely used synthetic dyes by natural colorants, such as henna and mixtures of henna with indigo. The aim of this study was to estimate the genotoxicity of water and DMSO solutions of indigo naturalis (prepared from Indigofera tinctoria leaves) using the cytokinesis-blocked micronucleus (CBMN) assay in the human metabolically active HepG2 cell line. The cytotoxic effects of indigo solutions were first assessed by propidium iodide and fluorescein-diacetate simultaneous staining. For both solutions, cytotoxicity was always under 10%. Data obtained in the CBMN assay (for all concentrations tested) indicated that the frequency of MN (micronuclei) in exposed cells was no higher than the control. Both the water and DMSO solutions showed the same behavior. These results indicate that indigo naturalis exhibits neither cytotoxicity, nor genotoxicity for all concentrations tested, which may justify excluding indigofera and its components from the list of carcinogenic agents.
  • Article
    Excess hepatic lipid accumulation and oxidative stress contribute to nonalcoholic fatty liver disease (NAFLD). Thus, we hypothesized that the hypolipidemic and antioxidant activities of green tea extract (GTE) would attenuate events leading to NAFLD. Obese mice (ob/ob; 5 weeks old, n=38) and their lean littermates (n=12) were fed 0%, 0.5% or 1% GTE for 6 weeks. Then, hepatic steatosis, oxidative stress and inflammatory markers were measured. Obese mice, compared to lean controls, had greater hepatic lipids and serum alanine aminotransferase (ALT). GTE at 1% lowered (P<.05) hepatic lipids and ALT in obese mice. The GTE-mediated attenuation in hepatic steatosis was accompanied by decreased mRNA expression of adipose sterol regulatory element-binding protein-1c, fatty acid synthase, stearoyl CoA desaturase-1, and hormone-sensitive lipase and decreased serum nonesterified fatty acid concentrations. Immunohistochemical data indicated that steatotic livers from obese mice had extensive accumulation of tumor necrosis factor-α (TNF-α), whereas GTE at 1% decreased hepatic TNF-α protein and inhibited adipose TNF-α mRNA expression. Hepatic total glutathione, malondialdehyde and Mn- and Cu/Zn-superoxide dismutase activities in obese mice fed GTE were normalized to the levels of lean littermates. Also, GTE increased hepatic catalase and glutathione peroxidase activities, and these activities were inversely correlated with ALT and liver lipids. Collectively, GTE mitigated NAFLD and hepatic injury in ob/ob mice by decreasing the release of fatty acids from adipose and inhibiting hepatic lipid peroxidation as well as restoring antioxidant defenses and decreasing inflammatory responses. These findings suggest that GTE may be used as an effective dietary strategy to mitigate obesity-triggered NAFLD.
  • Article
    Quercetin had been shown to be effective in the management of arthritis. However, bioavailability of quercetin is a concern for such treatment. This work aims at the development of intra-articular drug delivery system by controlled release of quercetin (loaded in microspheres) for the management of rheumatoid arthritis. Polycaprolactone has been used for the preparation of microspheres (with quercetin) using the solvent evaporation method. The physio-chemical characterisation of polycaprolactone-loaded quercetin microspheres was carried out to obtain information about particle size distribution, drug loading efficiency, morphology, thermal properties, polymorphism and release trends in phosphate-buffered saline at pH 7.4 and 37°C. Quercetin-loaded polycaprolactone microspheres were found to be biocompatible as evidenced from in vitro and in vivo studies using a rabbit synovial cells and Wistar rats, respectively. Quercetin release from microspheres of selected formulations showed biphasic nature due to initial burst effect followed by a controlled release. These results suggest that optimised quercetin-loaded polycaprolactone microspheres may be the viable strategy for controlled release of quercetin in the joint cavity for more than 30 days by intra-articular injection to treat rheumatoid arthritis.
  • Article
    The localization of atherosclerotic lesions to predictable regions in mammalian arteries has been recognized for over a century. We sought to investigate the association between oxidative stress and regional susceptibility of the mouse aorta to atherosclerosis. En face confocal microscopy was employed to assess oxidative stress in the aortic intima of atherosclerosis-susceptible and protected regions of wild-type C57BL/6 mouse. Expression of reactive oxygen species and antioxidant producing genes were compared in endothelial cells from the susceptible and protected regions. In vivo administration of redox-sensitive fluorescent dyes revealed an increase in the production of reactive oxygen species (ROS) in the atherosclerosis-susceptible regions relative to the protected regions. In contrast, Hoechst a redox-insensitive dye distributed evenly in the susceptible and protected regions. Accumulation of superoxide in the susceptible regions of the aorta was significantly blocked by the administration of Diphenyleneiodonium, a flavoprotein inhibitor. mRNA levels of superoxide-producing and scavenging enzymes were significantly increased in the regions predisposed to atherosclerosis. The regional difference in oxidative stress was at a lesser magnitude in BALB/c than the atherosclerosis-susceptible mouse (C57BL/6). Our study for the first time demonstrated an augmented oxidative stress in atherosclerosis-susceptible regions of the normal mouse aorta.
  • Article
    Nonalcoholic fatty liver disease is considered to be the hepatic manifestation of metabolic syndrome and is usually related to high-fat, high-cholesterol diets. With the rationale that the identification and quantification of metabolites in different metabolic pathways may facilitate the discovery of clinically accessible biomarkers, we report the use of (1)H NMR metabolomics for quantitative profiling of liver extracts from LDLr(-/-) mice, a well-documented mouse model of fatty liver disease. A total of 55 metabolites were identified, and multivariate analyses in a diet- and time-comparative strategy were performed. Dietary cholesterol increased the hepatic concentrations of cholesterol, triglycerides, and oleic acid but also decreased the [PUFA/MUFA] ratio as well as the relative amount of long-chain polyunsaturated fatty acids in the liver. This was also accompanied by variations of the hepatic concentration of taurine, glutathione, methionine, and carnitine. Heat-map correlation analyses demonstrated that hepatic inflammation and development of steatosis correlated with cholesterol and triglyceride NMR derived signals, respectively. We conclude that dietary cholesterol is a causal factor in the development of both liver steatosis and hepatic inflammation.
  • Article
    Nowadays, people's exposure to chemical compounds such as organophosphorus insecticides is continuously on the rise more and more. Theses compounds have induced an excessive production of free radicals which are responsible for several cell alterations in the organism. Recent investigations have proved the crucial role of nutritional antioxidants to prevent the damage caused by toxic compounds. In this study, we investigate the role of date palm fruit extract (Phoenix dactylifera L.) in protection against oxidative damage and hepatotoxicity induced by subchronic exposure to dimethoate (20mg/kg/day). Oral administration of dimethoate caused hepatotoxicity as monitored by the increase in the levels of hepatic markers enzymes (transaminases, alkaline phosphatase, gamma-glutamyl transferase and lactate dehydrogenase), as well as in hepatic malondialdehyde thus causing drastic alteration in antioxidant defence system. Particularly, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were found increased by dimethoate while catalase (CAT) activity was reduced significantly. These biochemical alterations were accompanied by histological changes marked by appearance of vacuolization, necrosis, congestion, inflammation, and enlargement of sinusoids in liver section. Pretreatment with date palm fruit extract restored the liver damage induced by dimethoate, as revealed by inhibition of hepatic lipid peroxidation, amelioration of SOD, GPx and CAT activities and improvement of histopathology changes. The present findings indicate that in vivo date palm fruit may be useful for the prevention of oxidative stress induced hepatotoxicity.
  • Article
    Plant secondary metabolites and their semi-synthetic derivatives continue to play an important role in anticancer drug therapy. In this short review, selected single chemical entity antineoplastic agents from higher plants that are currently in clinical trials as cancer chemotherapy drug candidates are described. These compounds are representative of a wide structural diversity. In addition, the approaches taken toward the discovery of anticancer agents from tropical plants in the laboratory of the authors are summarized. The successful clinical utilization of cancer chemotherapeutic agents from higher plants has been evident for about half a century, and, when considered with the promising pipeline of new plant-derived compounds now in clinical trials, this augurs well for the continuation of drug discovery research efforts to elucidate additional candidate substances of this type.
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    Full-text available
    There is increasing evidence that the HDL-associated enzyme paraoxonase 1 (PON1) may have a protective function in the atherosclerotic process. An enhancement of PON1 activity by dietary factors including flavonoids is therefore of interest. Quercetin, a flavonol frequently present in fruits and vegetables has been shown to induce PON1 in cultured liver cells, but the in vivo efficacy of a dietary quercetin supplementation has yet not been evaluated. To this end, we fed laboratory mice quercetin-enriched diets with quercetin concentrations ranging from 0.05 to 2 mg/g diet for 6 weeks and determined the expression of the hepatic PON1 gene and its protein levels. Since we could establish a moderate but significant induction of PON1 mRNA levels by dietary quercetin in mice, we aimed to proof whether healthy human volunteers, given graded supplementary quercetin (50, 100 or 150 mg/day) for two weeks, would respond with likewise enhanced plasma paraoxonase activities. However, PON1 activity towards phenylacetate and paraoxon was not changed following quercetin supplementation in humans. Differences between mice and humans regarding the PON1 inducing activity of quercetin may be related to differences in quercetin metabolism. In mice, unlike in humans, a large proportion of quercetin is methylated to isorhamnetin which exhibits, according to our reporter gene data in cultured liver cells, a potent PON1 inducing activity.
  • Article
    FHL2, a member of the four and a half LIM domain (FHL) family of proteins, may play an important role in the circulatory system and in particular atherosclerosis. To investigate the role of FHL2 in atherogenesis, FHL2-null and wild-type control male mice were fed either a normal chow (NC) or a cholesterol-enriched diet (CED). At 3 months post CED, aortic atherosclerotic plaques were observed in both control and FHL2-null mice. Lesions in control mice increased dramatically by 6 months of CED. In contrast, lesion size did not increase during this time in CED-fed FHL2-null mice. Relative to control mice on a normal chow of diet (NCD), control mice on a CED exhibited lower circulating nitric oxide (NO) levels, and decreased expression of connexin37 (Cx37) and Cx40 in aortic endothelium. In contrast, FHL2-null mice on a CED maintained similar levels of circulating NO as FHL2-null mice fed a NCD. Cxs levels in aortic endothelium of FHL2-null mutants on a NCD were lower relative to control mice on a NCD, and did not decrease with CED. Our data demonstrate a role for FHL2 in atherogenesis, the regulation of circular NO release, and expression of gap junctions within aortic endothelium.
  • Article
    The nutritional, phytochemical, antioxidant and antibacterial activities of the acetone, methanol and water extracts of the leaves of Solanum nigrum and Leonotis leonorus were investigated using standard analytical methods in order to assess the numerous potential of the leaves of these plants. The proximate analysis showed the that the leaves of the two plants were rich in moisture content, ash content, crude protein, crude lipid, crude fibre and carbohydrate. Elemental analysis in mg/100g (DW) indicated that the leaves contained sodium, potassium, calcium, magnesium, iron, zinc, phosphorus, copper, manganese, and nitrogen. The chemical composition in mg/100g (DW) for alkaloid, saponins, and phytate were moderate. The plants were also rich in polyphenols and had good antioxidant activities. The different extracts of the plants had activities against some of the organisms used in this study. Comparing the nutrient and chemical constituents with recommended dietary allowance (RDA) values, the results reveal that the leaves contain an appreciable amount of nutrients, minerals, and phytochemicals and low levels of toxicants.
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    Leukemia is the disorder of hematopoietic cell development and is characterized by an uncoupling of cell proliferation and differentiation. There is a pressing need for the development of novel tactics for leukemia therapy as conventional treatments often have severe adverse side effects. Tryptanthrin (6,12-dihydro-6,12-dioxoindolo-(2,1-b)-quinazoline) is a naturally-occurring, weakly basic alkaloid isolated from the dried roots of medicinal indigo plants (Ban-Lan-Gen). It has been reported to have various biological and pharmacological activities, including anti-microbial, anti-inflammatory, immunomodulatory and anti-tumor effects. However, its modulatory effects and action mechanisms on myeloid cells remain poorly understood. In this study, tryptanthrin was shown to suppress the proliferation of the murine myeloid leukemia WEHI-3B JCS cells in a dose- and time-dependent manner. It also significantly reduced the growth of WEHI-3B JCS cells in vivo in syngeneic BALB/c mice. However, it exhibited no significant direct cytotoxicity on normal murine peritoneal macrophages. Flow cytometric analysis showed an obvious cell cycle arrest of the tryptanthrin-treated WEHI-3B JCS cells at the G0/G1 phase. The expression of cyclin D2, D3, Cdk 2, 4 and 6 genes in WEHI-3B JCS cells was found to be down-regulated at 24 h as measured by RT-PCR. Morphological and functional studies revealed that tryptanthrin could induce differentiation in WEHI-3B JCS cells, as shown by the increases in vacuolation, cellular granularity and NBT-reducing activity in tryptanthrin-treated cells. Collectively, our findings suggest that tryptanthrin might exert its anti-tumor effect on the murine myelomonocytic leukemia WEHI-3B JCS cells by causing cell cycle arrest and by triggering cell differentiation.
  • Article
    Garlic and white and red varieties of onion were subjected to processing by a variety of culinary methods, and bioactive compounds then determined. For in vivo studies, 84 male Wistar rats were randomly divided into 14 diet groups, each of six rats, including two control groups (one with no supplementation and one with cholesterol supplementation only). During the 30-day trial, the basal diets of the other 12 groups were supplemented with 1% cholesterol and raw or processed vegetables. Both raw red onion and red onion subjected to blanching for 90 s hindered the rise in plasma lipids more than the other vegetables studied in the supplemented diets. The decrease in antioxidant activity compared to the cholesterol-supplemented control group was significantly less for the group fed with red onion subjected to blanching for 90 s. No histological changes were detected in the studied organs of rats that had been fed cholesterol. In conclusion, blanching for 90 s most fully preserved the bioactive compounds and antioxidant potentials, and hindered the rise in plasma lipid levels and the decrease in plasma antioxidant activity of rats fed cholesterol. Alkaline phosphatase levels correlated with classical atherosclerosis indices, and determination of alkaline phosphatase is suggested as an additional index in atherosclerosis testing.
  • Article
    The interactions of lysozyme with caffeine (Caf), theophylline (Tph) and theobromine (Tbr) were investigated using UV–Vis absorption, fluorescence, synchronous fluorescence, and three-dimensional fluorescence spectra techniques. The results revealed that Caf (Tph or Tbr) caused the fluorescence quenching of lysozyme by the formation of Caf (Tph or Tbr)–lysozyme complex. The binding constants (K A) and thermodynamic parameters (ΔG°, ΔH°, ΔS°) at two different temperatures, the binding locality, and the binding power were obtained. The results showed that the process of binding Caf (Tph or Tbr) to lysozyme was a spontaneous molecular interaction procedure and the hydrophobic and electrostatic interactions play a major role in stabilizing the complex; The distance r between donor (lysozyme) and acceptor (Caf, Tph or Tbr) was obtained according to fluorescence resonance energy transfer. The effect of Caf (Tph or Tbr) on the conformation of lysozyme was analyzed using synchronous fluorescence and three-dimensional fluorescence spectra techniques. The results showed that the binding of Caf (Tph or Tbr) to lysozyme induced some micro-environmental and conformational changes in lysozyme and disturbed the environment of the polypeptide of lysozyme.
  • Article
    Lipid entrapment property of polysaccharide gel (PG) extracted from fruit-hulls of durian (Durio zibethinus Murr. Cv. Mon-Thong) was investigated in vitro by semi- permeable membrane dialysis technique using both cellulose membrane and gut sacs of disected jejunum of rat. Lipids (cholesterol, oleic acid and stearic acid) were mixed with 0-2%W/V PG in the presence of bile salt as a surface active agent in dialysis membrane. Lipids inside and outside dialysis membrane were analyzed by HPLC method after 4-16 hours of dialysis in Ringer lactate buffer pH7. Increasing PG concentration resulted in increasing lipids trapped inside membrane and decreasing lipids released outside membrane. Two percent PG trapped about 80-90%cholesterol. The result of PG trapping cholesterol in egg york showed that egg york cholesterol released outside membrane was decreased with increasing PG concentration. A significant relationship was found between the decreasing of absorbed cholesterol into everted rat jejunum with respect to increasing concen- tration of PG. These results suggested that durian polysaccharide gel is able to entrap lipids and it seems to have potential use as medicinal dietary food for lipid controlling patient. Furthermore, in vitro study using cellulose semi- permeable membrane dialysis method may be applied for preliminary evaluation of polysaccharide effecting lipids absorption.
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    In order to preserve the ancestral knowledge, an ethnopharmacological study has been carried out in two councils belonging to Trás-os-Montes region a small area located in the northern of Portugal. In that area, medicinal plants, most of the species wild, are still in use among farmers, shepherds and other people who live far from villages and built-up areas. Among the 46 people that were interviewed (mean age of 66 years old), 88 species belonging to 42 families of vascular plants were identified for treatment of various human ailments. An ethnopharmacological report is made consisting of species names, vernacular names, popular uses of the plants and their pharmacological properties. The most dominant family is Lamiaceae (18%) and the most frequently part of the plant used for the treatment of diseases are leaves (37.9%). The largest number of taxa is used to treat gastrointestinal disorders (73.9%).
  • Article
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    Infectious diseases, especially those affecting the respiratory tract, represent a critical problem to health. Crude methanol and water extracts of 10 Venda plants reported to be used ethnomedically in the treatment of respiratory conditions were assessed for their antimicrobial activity against standard strains and clinical isolates of Candida albicans, Haemophilis influenzae, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus pneumoniae, and Mycobacterium smegmatis using the disc diffusion assay. Four of the 10 plants tested possessed antimicrobial activity, but no activity against K. pneumoniae was observed. Minimum inhibitory concentrations, as determined by the broth microdilution assay, showed three plants, Securidaca longepedunculata, Syzygium cordatum, and Tabernaemontana elegans, to possess MICs </= 1 mg/mL. Phytochemical screening, performed by separation on thin layer chromatography using a variety of mobile phases and visualization with spray reagents as well as UV light showed various classes of compounds in the active extracts. Some of these have been associated with antioxidant activity, as confirmed in this study. Moreover, these extracts showed toxicity in vitro to lymphocytes. Although three plant species with significant antimicrobial activity were identified, there is a need for further scientific evaluation regarding identification of the bioactive constituents, as well as their toxicity.
  • Article
    The effects of the administration of water soluble coenzyme Q10 (25 mg/kg per day) over 30 days, after 50 days feeding on a high-fat diet (3% lard + 1.3% cholesterol), were investigated in the plasma and liver mitochondria of rabbits. Results showed that this atherogenic diet enhanced lipid levels both in plasma and liver mitochondria, reduced plasma and mitochondrial concentrations of retinol and coenzyme Q10, led to higher DNA damage in peripheral blood lymphocytes and reactive oxygen species concentration in liver mitochondria. The treatment of animals with coenzyme Q10 reduced (to the healthy group levels) lipid concentration in liver mitochondria with no effect on plasma lipids, increased mitochondrial levels of alpha-tocopherol, restored mitochondrial coenzyme Q10 and improved alpha-tocopherol levels in plasma. Moreover, coenzyme Q10 supplementation reduced mitochondrial reactive oxygen species levels and decreased DNA damage in peripheral blood lymphocytes. The findings suggest that antioxidant therapy with coenzyme Q10 may be used in the treatment of liver pathologies associated to the intake of high-fat, atherogenic, diets.
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    The antioxidant activities of different durian cultivars at the same stage of ripening (Mon Thong, Chani, Kan Yao, Pung Manee and Kradum) were compared in order to choose the best as a supplement in the human diet. Total polyphenols (mg gallic acid equivalent/100 g fresh weight (FW)) and flavonoids (mg catechin equivalent (CE)/100 g FW) in Mon Thong (361.4+/-23.2 and 93.9+/-7.4) were significantly higher (P<0.05) than in Kradum (271.5+/-11.2 and 69.2+/-5.3) and Kan Yao (283.2+/-16.5 and 72.1+/-6.8). The free polyphenols and flavonoids showed lower results than the hydrolyzed ones. Anthocyanins (microg cyanidin-3-glucoside equivalent/100 g FW) and flavanols (microg CE/100 g FW) were significantly higher in Mon Thong (427.3+/-23.8 and 171.4+/-16.3) than in Kradum (320.2+/-12.1 and 128.6+/-9.7) and Kan Yao (335.3+/-14.1 and 134.4+/-11.7). Ultraviolet spectroscopy and high-performance liquid chromatography/diode array detection analyses showed that caffeic acid and quercetin were the dominant bioactive substances in Mon Thong cultivar. The antioxidant activity (microM trolox equivalent/100 g FW) of Mon Thong cultivar (260.8+/-20.2, 1,075.6+/-81.4 and 2,352.7+/-124.2) determined by ferric-reducing/antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) with Trolox equivalent antioxidant capacity (TEAC) assays was significantly higher (P<0.05) than in Kradum (197.4+/-8.9, 806.5+/-31.2 and 1,773.2+/-102.5) and in Kan Yao (204.7+/-9.7, 845.5+/-48.6 and 1,843.6+/-107.5). The correlation coefficients between polyphenols, flavonoids, flavanols and FRAP, CUPRAC and TEAC capacities were between 0.89 and 0.98. In extracted and separated by electrophoresis durian proteins, some differences were found in the sodium dodecyl sulfate-protein bands in the region of 16 and 68 kDa for Kradum, 45 kDa for Mon Thong and three bands for Kan Yao. Antioxidants and proteins can be used for characterization of the quality of durian cultivars. In conclusion, the bioactivity of durian cultivars Mon Thong, Chani and Pung Manee was high and the total polyphenols were the main contributors to the overall antioxidant capacity. The results of our investigation in vitro are comparable with other fruits that widely used in human diets. Therefore, Durian can be used as a supplement for nutritional and healthy purposes, especially Durian Mon Thong, Chani and Pung Manee.
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