Dietary Sources Of Natural Antioxidants Research Articles

Comparative studies of antioxidant activity and profile of some spices

Compounds that prevent or slow down the oxidation of lipids or other molecules like free radicals are known as antioxidants. The Study evaluated the antioxidant capacity, hydrogen peroxide scavenging capacity, and total flavonoid and phenol contents of six spices. Dried samples of spices were extracted in distilled water and analyzed using spectrophotometric and titrimetric methods. TAC results ranged from 232.79 - 64.32 mg/100g, with clove and black cardamom exhibiting the highest and lowest antioxidant activity respectively. The H2O2 scavenging activities result had clove and rosemary with the highest scavenging activity. Rosemary had the highest total phenol (5060 mg/100g) and flavonoid (1339 mg/100g) contents while black cardamom had the lowest values in both. Spices could be substituted for synthetic antioxidants in the food industry and as dietary sources of natural antioxidants.

Determination of total phenolic content in different vegetables

The word polyphenol is that chemical substance having more than one phenol group. Polyphenols represent a variety of compounds of plant origin. Polyphenols have potential use in the human body. They act as antioxidants preventing oxidation of other molecules by formation of free radicals in the body. Most of the polyphenols have properties of reducing agents. They protect cell constituents against oxidative damage. Therefore polyphenols reduce risk of various degenerative diseases related to oxidative stress. In addition to antioxidant properties, they also have antimicrobial as well as anti-inflammatory properties. They enhance body immunity. Polyphenol intake or consumption of polyphenol-rich foods has been studied in several epidemiological studies. Many studies on the antioxidant properties of vegetables suggested that vegetables are excellent dietary sources of natural antioxidants. Polyphenols are natural antioxidants present in all foods. The study was conducted to determine total phenolic content in various vegetables. Total phenolic content estimated in vegetables were compared. Total phenols are estimated by Folin Denis reagents that produce blue color with polyphenols. Tannic acid was used as standard and results were expressed as tannic acid equivalent (Singh and Jambunathan, 1981). Result: Total polyphenol contents in present study showed variation within vegetables estimated. Mean polyphenol content in vegetables was found to be highest 5.3g/100g in amla, followed by mint 1.1g/100g, 844 mg/100g in coriander green and 586 mg/100g in lady finger. Amla was characterized as the highest polyphenol content (538 mg/100g) on a fresh weight basis, whereas the lowest mean polyphenol content (17.50mg/100g) was found in cucumber. Conclusion: fruits and vegetables must be included in our daily diet for good health.

Ultrasound-Assisted Extraction, Identification, and Quantification of Antioxidants from 'Jinfeng' Kiwifruit.

Kiwifruit (Actinidia chinensis) is a nutrient-dense fruit abundant in vitamin C and phenolic compounds, and it exhibits strong antioxidant capacity. However, the antioxidants in ‘Jinfeng’ kiwifruit have seldom been extracted and analyzed, and the conditions for the extraction of kiwifruit antioxidants by ultrasound-assisted extraction (UAE) have seldom been investigated. In this study, response surface methodology (RSM) was used to optimize UAE conditions to extract antioxidants from ‘Jinfeng’ kiwifruit. In addition, the antioxidant capacity, contents of total phenolics and total flavonoids, ascorbic acid, and the profiles of antioxidants were also analyzed. The results showed that the optimal UAE conditions included 68% ethanol, liquid/solid ratio at 20 mL/g, extraction time at 30 min, extraction temperature at 42 °C, and ultrasonic power at 420 W. Under these conditions, the ABTS value of kiwifruit was 70.38 ± 1.38 μM TE/g DW, which was 18.5% higher than that of the extract obtained by conventional solvent extraction. The total phenolic and flavonoid contents were 15.50 ± 0.08 mg GAE/g DW and 5.10 ± 0.09 mg CE/g DW, respectively. Moreover, 20 compounds were tentatively identified by UPLC–MS/MS, and the content of main compounds, such as procyanidin B2, neochlorogenic acid, and epicatechin, were determined by HPLC–DAD. This research revealed the profiles of antioxidant phytochemicals in ‘Jinfeng’ kiwifruit, which can be a good dietary source of natural antioxidants with potential health functions.

A comparative study of growth, biological efficiency, antioxidant activity and molecular structure in wild and commercially cultivated Auricularia cornea strains

Abstract Auricularia cornea, jelly mushroom, is a popular ingredient of traditional Chinese cuisine. This study aimed at evaluating the growth, yield, biological efficiency, total phenolic and flavonoid contents, the antioxidant activity, elemental composition, and molecular structure of the wild and domesticated strain Ac24 and the commercially cultivated edible mushroom A. cornea strains Ac1, Ac3 and Ac15. Based on the weight of the fresh fruiting bodies of A. cornea strains, the maximum yield was obtained from commercial strain Ac1 (237.10 g), followed by Ac3 (224.47 g), Ac15 (158 g) and Ac24 (132.37 g), while the biological efficiency range of A. cornea strains was 52.94–94.84%, with significant differences among the A. cornea strains. Our results revealed that Ac24 contained the highest phenolic content (20.10 mg GAE · g−1), while the highest flavonoid content was found in Ac1 (35.13 mg CE · g−1). The maximum mineral contents and the strains were as follows: copper (7.2 mg · kg−1) and zinc (310 mg · kg−1) in Ac1, manganese (788 mg · kg−1) in Ac3 and iron (310 mg · kg−1) in Ac24. DPPH assay found maximum antioxidant activity in Ac24 (IC50 0.233 mg TX · mL−1), FRAP (591 mg TX · g−1) in Ac15, and erythrocyte haemolysis in Ac24. SEM-EDX and FTIR analyses verified the differences among A. cornea strains. The results revealed that wild, domesticated A. cornea strain Ac24 is a promising dietary source of natural antioxidants and is of high nutritional value, compared to commercially cultivated strains.

Phenolic Profiles, Antioxidant Capacities, and Inhibitory Effects on Digestive Enzymes of Different Kiwifruits.

In order to obtain high-quality kiwifruits with health-promoting characteristics, physicochemical properties, phenolic profiles, antioxidant capacities, and inhibitory effects on digestive enzymes (pancreatic lipase and α-glucosidase), of fourteen different types of kiwifruit obtained from China were systematically investigated and compared. Noticeable variations in the fruits’ physicochemical properties and phenolic profiles were observed among them. The total phenolic content of Actinidia chinensis cv. Hongshi, A. chinensis cv. Jinshi, and A. chinensis cv. Jinlong were 16.52 ± 0.26 mg GAE/g DW (dry weight), 13.38 ± 0.20 mg GAE/g DW, and 11.02 ± 0.05 mg GAE/g DW, respectively, which were much higher than those of the other tested kiwifruits. According to high performance liquid chromatography (HPLC) analysis, phenolic compounds, including procyanidin B1, procyanidin B2, (−)-epicatechin, chlorogenic acid, gallic acid, and quercetin-3-rhamnoside, were found to be the major compounds in kiwifruits, while procyanidin B1, procyanidin B2, and chlorogenic acid were the most abundant phenolic compounds. Furthermore, all the tested kiwifruits exerted remarkable antioxidant capacities and inhibitory effects on pancreatic lipase and α-glucosidase. Indeed, A. chinensis cv. Hongshi, Actinidia chinensis cv. Jinshi, and Actinidia chinensis cv. Jinlong exhibited much better antioxidant capacities and inhibitory effects on digestive enzymes than those of the other tested kiwifruits. Particularly, A. polygama showed the highest inhibitory activity on α-glucosidase. Therefore, Actinidia chinensis cv. Hongshi, Actinidia chinensis cv. Jinshi, and Actinidia chinensis cv. Jinlong, as well as A. polygama could be important dietary sources of natural antioxidants and natural inhibitors against pancreatic lipase and α-glucosidase, which is helpful for meeting the growing demand for high-quality kiwifruits with health-promoting characteristics in China.

Storage of Fruits and Vegetables in Refrigerator Increases their Phenolic Acids but Decreases the Total Phenolics, Anthocyanins and Vitamin C with Subsequent Loss of their Antioxidant Capacity.

It is of paramount importance for consumers, scientists and industrialists to understand how low-temperature storage of food items affects their bioactive compounds and properties. This study evaluated the effects of cold storage on total phenolics (TP), phenolic acids profile (PA), total anthocyanins (TA), total ascorbic acid (Vit. C) and antioxidant activity (AA) of 19 fruits and vegetables, collected from local Indian markets and stored in refrigerator (4 °C) during 15 days. Content of TP was highest in dill and amaranth and decreased (up to 29.67%) with storage. Leafy vegetables (amaranth, dill, onion, fenugreek and spinach) contained higher amounts of the 12 PA revealed by UPLC-UV; ellagic, gallic, sinapic and vanillic acids levels were the highest; chlorogenic acid (ρ = 0.423), syringic acid (ρ = 0.403) and sinapic acid (ρ = 0.452) mostly correlated with TP; and the PA increased during storage. Highest contents of Vit C estimated by AOAC, DCPIP and DNP methods were found in amaranth, dill and pomegranate, and decreased with storage. Pomegranate showed highest TA levels and low-temperature storage did not significantly increase TA, which was the largest contributor of TP in fruits and vegetables (ρ = 0.661). Storage induced a drastic decrease of AA, which mostly correlated with TP (ρ = 0.808, 0.690 and 0.458 for DPPH, ABTS and FRAP assays, respectively). Spearman’s correlation confirmed by principal component analysis demonstrated that dill, pomegranate and amaranth had the highest overall antioxidant capacity, whereas orange juice and carrot showed the lowest. The results provide support for a key-role of TP, followed by Vit. C and TA in antioxidant capacity of fruits and vegetables, which could be interesting dietary sources of natural antioxidants for prevention of diseases caused by oxidative stress.

Characterization of phenolic compounds in chia (Salvia hispanica L.) seeds, fiber flour and oil

The consumption of chia seeds products has increased recently and it has been suggested that the inclusion of this functional food in a daily human diet could contribute to improve consumers’ health. However, a better knowledge about the composition of these products is mandatory. In this work, the phenolic compounds from commercial samples of chia seed, fiber flour and oil were extracted using an ultrasound-assisted methodology and were separated and identified by high-performance liquid chromatography coupled to a mass spectrometer. Methanol:water extracts were prepared and submitted to an acidic hydrolysis. Crude and hydrolyzed extracts were analyzed and phenolic compounds found were mainly caffeic acid and danshensu and its derivatives, such as rosmarinic and salvianolic acids. TPC was higher in the hydrolyzed extracts. These results supply new information about the main phenolic compounds presents in chia, which are important dietary sources of natural antioxidants for prevention of diseases caused by oxidative stress.

The Phenolic Contents and Antioxidant Activities of Infusions of Sambucus nigra L.

The aim of this work was to evaluate the antioxidant potential of teas prepared from twenty-four commercially available berries and flowers of Sambucus nigra L. in relation to their phenolic profile, as reflected by the most representative phenolic acids (caffeic, chlorogenic, p-coumaric, ferulic, gallic and syringic acids); flavonols (quercetin, kaempferol, myricetin and rutin); and total phenolic (TPC), phenolic acid (TAC) and flavonoid (TFC) contents. The infusions prepared from elderflowers contained more abundant phenolic compounds than the elderberry infusions. The TPC of these infusions ranged from 19.81 to 23.90 mg of gallic acid equivalents/g dry weight of sample (GAE/g DW) for elderberries and from 15.23 to 35.57 mg GAE/g DW for elderflowers, whereas the TFC ranged from 2.60 to 4.49 mg of rutin equivalents/g dry weight of sample (RUTE/g DW) in elderberry infusions and from 5.27 to 13.19 mg RUTE/g DW in elderflower infusions. Among the phenolic compounds quantified in this study, quercetin (2.07–9.48 mg/g DW) and myricetin (1.17–9.62 mg/g DW) had the highest concentrations in the teas prepared from berries and flowers, respectively. Moreover, the antioxidant potential of elder infusions assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and ferric reducing antioxidant power (FRAP) assays revealed that the teas prepared from flowers had higher mean DPPH and FRAP activities than the teas prepared from berries. Therefore, elder beverages could be important dietary sources of natural antioxidants that contribute to the prevention of diseases caused by oxidative stress.

Antioxidant properties and color parameters of herbal teas in China

The popularity of herbal tea is increasing in China because of its beneficial effect on human health, especially for antioxidant function. Color is one of the important organoleptic characteristics of tea. The aim of this study was to supply new information on the antioxidant properties and color parameters of herbal teas for researchers and the general public. The in vitro antioxidant properties and color parameters of 110 herbal teas were systematically investigated in comparison with eight green teas in China. The results showed that the antioxidant property values and color parameters of herbal teas were more variable than those of green teas. The antioxidant property values of most herbal teas were lower than those of green teas, except for a few herbal teas with high values, which could be analogous or superior to green teas. Rattan tea ‘Teng Cha' (Ampelopsis grossedentata (Hand.-Mazz.) W. T. Wang) and Chinese rose tea ‘Yue Ji Hua' (Rosa chinensis Jacq.) showed significantly higher property values than green teas. Among all the herbal teas, a highly significant correlation coefficient was found between antioxidant capacity and total phenolic content. No significant correlations were detected between the color parameters and the antioxidant properties. Principal component analysis and hierarchical cluster analysis showed that the properties of five herbal teas were similar to green teas, whereas Yue Ji Hua and Teng Cha were superior to green teas. The results suggested that the some commonly consumed herbal teas in China might be promising and economic dietary sources of natural antioxidants.

Physicochemical, nutritional, and sensory analyses of a nitrate-enriched beetroot gel and its effects on plasmatic nitric oxide and blood pressure

BackgroundBeetroot (Beta vulgaris L.) is a dietary source of natural antioxidants and inorganic nitrate (). It is well known that the content of antioxidant compounds and inorganic nitrate in beetroot can reduce blood pressure (BP) and the risk of adverse cardiovascular effects.ObjectiveThe aim of the present study was to formulate a beetroot gel to supplement dietary nitrate and antioxidant compounds able to cause beneficial health effects following acute administration.Design and subjectsA beetroot juice produced from Beta vulgaris L., without any chemical additives, was used. The juice was evaluated by physicochemical and microbiological parameters. The sample was tested in five healthy subjects (four males and one female), ingesting 100 g of beetroot gel.ResultsThe formulated gel was nitrate enriched and contained carbohydrates, fibers, saponins, and phenolic compounds. The formulated gels possess high total antioxidant activity and showed adequate rheological properties, such as high viscosity and pleasant texture. The consumer acceptance test for flavor, texture, and overall acceptability of beetroot gel flavorized with synthetic orange flavor had a sensory quality score >6.6. The effects of acute inorganic nitrate supplementation on nitric oxide production and BP of five healthy subjects were evaluated. The consumption of beetroot gel increased plasma nitrite threefold after 60 min of ingestion and decreased systolic BP (−6.2 mm Hg), diastolic BP (−5.2 mm Hg), and heart rate (−7 bpm).

The effect of tomato juice supplementation on biomarkers and gene expression related to lipid metabolism in rats with induced hepatic steatosis.

Tomato products are a dietary source of natural antioxidants, especially lycopene, which accumulates in the liver, where it exerts biological effects. Taking into consideration this fact, the aim of the present study was to ascertain the effect of tomato consumption on biomarkers and gene expression related to lipid metabolism in rats with induced steatosis. Adult male Sprague-Dawley rats (8 weeks old) were randomly grouped (n = 6 rats/group) in four experimental groups: NA (normal diet and water), NL (normal diet and tomato juice), HA (high fat diet and water) and HL (high fat diet and tomato juice). After 7 weeks, rats were euthanized, and plasma, urine, feces and liver were sampled to analyze the biomarkers related to lipid metabolism, inflammation and oxidative stress. The H diet induced steatosis (grade II) in the HA and HL groups, which was confirmed by the levels of alanine aminotransferase and aspartate aminotransferase, histological examination and the presence of dyslipidemia. The intake of tomato juice led to an accumulation of all-E and Z-lycopene and its metabolites in the livers of these animals; levels were higher in HL than in NL, apparently due to higher absorption (63.07 vs. 44.45%). A significant improvement in the plasma level of high-density lipoprotein was observed in the HL group compared with HA animals, as was an alleviation of oxidative stress through reduction of isoprostanes in the urine. In relation to fatty acid gene expression, an overexpression of several genes related to fatty acid transport, lipid hydrolysis and mitochondrial and peroxisomal β-fatty acid oxidation was observed in the HL group. The consumption of tomato juice and tomato products reduced hallmarks of steatosis, plasmatic triglycerides and very low-density lipoproteins, and increased lipid metabolism by inducing an overexpression of genes involved in more efficient fatty acid oxidation.

Comprehensive evaluation of antioxidant and antimicrobial properties of different mushroom species

Antioxidant properties of mushroom extracts sequentially isolated by cyclohexane, dichloromethane, methanol, and water from Phaeolus schweinitzii, Inonotus hispidus, Tricholoma columbetta, Tricholoma caligatum, Xerocomus chrysenteron, Hydnellum ferrugineum, Agaricus bisporus and Pleurotus ostreatus were evaluated by DPPH, ABTS+ scavenging capacity, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and Folin–Ciocalteu total phenolic content (TPC) methods. The integrated values (‘antioxidant scores’) for evaluating antioxidant potential of extracts and dry mushroom substances are proposed. Antimicrobial activity was screened against Gram-positive (Bacillus cereus), Gram-negative (Pseudomonas aeruginosa) bacteria and fungi (Candida albicans) by agar diffusion method. The highest antioxidant capacity values (in μM TE/g extract dw) were found for methanol fractions of P. schweinitzii (9.62 ± 0.03 in DPPH; 109 ± 3 in FRAP; 164 ± 1 in ABTS+; 340 ± 3 in ORAC assays) and I. hispidus (9.5 ± 0.04 in DPPH; 54.27 ± 0.46 in ABTS+; 88.31 ± 1.96 in FRAP; 290 ± 1 in ORAC assays). Extracts of other species possessed considerably lower antioxidant activities. The extracts of I. hispidus were more effective against tested microbial species than other mushrooms. In conclusion, our results show that some wild mushrooms might be promising dietary sources of natural antioxidants and antimicrobial agents.

Phytochemicals and antioxidant activities of Rhus tripartitum (Ucria) fruits depending on locality and different stages of maturity

The phytochemical content (total phenolic compounds, total flavonoids, condensed tannins and phenolic composition) and the antioxidant potential of Rhus tripartitum fruits collected from different localities were screened during maturity. Significant variability was detected. HPLC analyses revealed the presence of 24 compounds with notable differences. Flavone and betulinic acid, which have numerous benefits, were the main detected compounds (more than 73%). This work highlights the importance of R. tripartitum fruits as dietary sources of natural antioxidants, and might be appropriate for the development of reliable index to estimate fruit richness with bioactive molecules.

Reversed-phase ultra-high-performance liquid chromatography coupled to electrospray ionization-quadrupole-time-of-flight mass spectrometry as a powerful tool for metabolic profiling of vegetables: Lactuca sativa as an example of its application

Lettuce (Lactuca sativa), a leafy vegetal widely consumed worldwide, fresh cut or minimally processed, constitutes a major dietary source of natural antioxidants and bioactive compounds. In this study, reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) coupled to electrospray ionization-quadrupole-time-of-flight mass spectrometry (ESI-QTOF-MS) was applied for the comprehensive profiling of polar and semi-polar metabolites from three lettuce cultivars (baby, romaine, and iceberg). The UHPLC systems allowed the use of a small-particle-size C18 column (1.8μm), with very fine resolution for the separation of up to seven isomers, and the QTOF mass analyzer enabled sensitive detection with high mass resolution and accuracy in full scan. Thus, a total of 171 compounds were tentatively identified by matching their accurate mass signals and suggested molecular formula with those previously reported in family Asteraceae. Afterwards, their structures were also corroborated by the MS/MS data provided by the QTOF analyzer. Well-known amino acids, organic acids, sesquiterpene lactones, phenolic acids and flavonoids were characterized, e.g. lactucin, lactucopicrin, caftaric acid, chlorogenic acid, caffeoylmalic acid, chicoric acid, isochlorogenic acid A, luteolin, and quercetin glycosides. For this plant species, this is the first available report of several isomeric forms of the latter polyphenols and other types of components such as nucleosides, peptides, and tryptophan-derived alkaloids. Remarkably, 10 novel structures formed by the conjugation of known amino acids and sesquiterpene lactones were also proposed. Thus, the methodology applied is a useful option to develop an exhaustive metabolic profiling of plants that helps to explain their potential biological activities and folk uses.

Textural Characteristic, Antioxidant Activity, Sugar, Organic Acid, and Phenolic Profiles of 10 Promising Jujube (Ziziphus jujuba Mill.) Selections

Ten promising jujubes were analyzed for textural characteristic (hardness), antioxidant activity, sugar, organic acid, and phenolic profiles. Total phenolic content (TP) measured by Folin-Ciocalteu method ranged from 275.6 to 541.8 mg of gallic acid equivalents per 100 g fresh weight (mg GAE/100 g FW). Four sugars (rhamnose, fructose, sucrose, and glucose), 3 organic acids (malic, citric, and succinic acids), and 11 phenolic compounds (gallic acid, protocatechuic acid, cinnamic acid, chlorogenic acid, caffeic acid, ferulic acid, ellagic acid, catechin, epicatechin, rutin, and quercetin) were identified and quantified by high-performance liquid chromatography in jujube fruits. The results showed that ascorbic acid and proanthocyanidins contents were positively correlated with hardness, and antioxidant activity was well correlated with TP content. Among 10 jujube cultivars, Zizyphus jujuba cv. Qingjianmuzao is good for direct consumption containing high levels of total soluble solids, total sugars, fructose, and glucose, while Zizyphus jujuba cv. Jiaxianmuzao could be an important dietary source of natural antioxidants. Genotype is the main factor influencing the composition of bioactive compounds in jujubes. Zizyphus jujuba cv. Qingjianmuzao is good for direct consumption, while Zizyphus jujuba cv. Jiaxianmuzao could be an important dietary source of natural antioxidants for prevention of diseases caused by oxidative stress.

Antioxidant capacities, phenolic compounds and polysaccharide contents of 49 edible macro-fungi

Edible macro-fungi are widely consumed as food sources for their flavors and culinary features. In order to explore the potential of macro-fungi as a natural resource of bioactive compounds, the antioxidant properties and polysaccharide contents of 49 edible macro-fungi from China were evaluated systematically. A positive correlation between antioxidant capacity and total phenolic content indicated that phenolic compounds could be main contributors of antioxidant capacities of these macro-fungi. Furthermore, many bioactive compounds such as gallic, homogentisic, protocatechuic, and p-hydroxybenzoic acid were identified and quantified. The macro-fungi species Thelephora ganbajun Zang, Boletus edulis Bull., Volvariella volvacea Sing, Boletus regius Krombh, and Suillus bovinus Kuntze displayed the highest antioxidant capacities and total phenolic contents, indicating their potential as important dietary sources of natural antioxidants.

Characteristics of Seed Oils from Four Blackberries Varieties (<i>Rubus</i> L.)

The content and composition of fatty acids in the seed oil from 4 blackberry varieties were compared in this paper to provide further guidelines for use of blackberry seeds. Blackberry seed oil contains rich α-linolenic and linoleic acid making it an excellent dietary source of 18:3n-3 and essential fatty acids. The oil is a good dietary source of natural antioxidants for health promotion and disease prevention. The presence of n-3 fatty acid and antioxidants also suggests potential value-added utilization of blackberry seeds for preparing functional foods or supplemental products.

Antioxidant Vitamins and Cardiovascular Disease

Cardiovascular disease represents an unparalleled proportion of the global burden of disease and will remain the main cause of mortality for the near future. Fortunately, most premature cardiovascular deaths are preventable. Therefore, prevention becomes vital and diet has shown beneficial effects to protect from CVD (CVD). Fruits and vegetables are dietary sources of natural antioxidants and it is generally accepted that antioxidants in these foods are key in explaining the inverse association between fruits and vegetables intake and the risk of developing a cardiovascular event or having elevated levels of cardiovascular risk factors. Available evidence supports the central role of oxidative stress in the atherosclerosis process and the correlation between increased oxidative stress and vascular disease. Theoretically, antioxidants in fruits and vegetables are important in inhibiting oxidative mechanisms that lead to various degenerative diseases including CVD. However, results from many interventional trials using antioxidants given as supplements have not been concordant with previous positive findings from observational epidemiologic cohort studies. The present manuscript gives a brief overview of the relationship between natural antioxidants (specially vitamin C, vitamin E and beta-carotene) intake and the risk of CVD.

Nutritional evaluation and antioxidant activity of sesame sprouts

Sesame sprouts are consumed as vegetables in Asian folk. In this study, the nutritional evaluation and antioxidant activity of sesame sprouts were investigated. As seeding days progressed, the free amino acids, γ-aminobutyric acid and total phenolic compounds in the sprouts were rapidly increased while sesamin was reduced. Although a fatty acid composition analysis showed that sesame sprouts were abundant in unsaturated fatty acids, the crude fat content was gradually reduced during sprout growth. In the antioxidant assays, it was found that the DPPH radical scavenging activity and the reducing power of the sprouts increased as the seeding days progressed, which was positively related to the total phenolic content. Sesame sprouts can be recommended for functional ingredients, as well as being an excellent dietary source of natural antioxidants.

Antioxidant capacities and total phenolic contents of 62 fruits

In order to supply new information on the antioxidant function of selected fruits for nutritionists and the general public, antioxidant activities and total phenolic contents of 62 fruits were evaluated using ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) assays as well as the Folin–Ciocalteu method, respectively. The correlations between the FRAP value and the TEAC value as well as total phenolic content were also assessed. The results showed that different fruits had diverse antioxidant capacities and the variation was very large, and seven fruits, Chinese date, pomegranate, guava, sweetsop, persimmon, Chinese wampee and plum, possessed the highest antioxidant capacities and total phenolic contents among tested fruits, and could be important dietary sources of natural antioxidants for prevention of diseases caused by oxidative stress.