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1.
为探究普洱茶仓储陈化过程中酚类物质等品质成分变化及其对抗氧化能力的影响,采用高效液相色谱(HPLC)等方法对6个系列3个不同仓储期共18款普洱茶(生茶)中的17种酚类化合物、3种嘌呤碱等品质成分进行定量检测.并对普洱茶(生茶)的铁离子还原/抗氧化能力、DPPH自由基清除能力、ABTS自由基清除能力、羟基自由基清除能力和...  相似文献   

2.
Aqueous acetone extracts prepared from five Indigofera species of Burkina Faso, namely Indigofera colutea (Burm.) Murril., I. macrocalyx Guilld et Perr., I. nigritana Hook f., I. pulchra willd. and I. tinctoria L., were investigated for their phytochemical composition and their antioxidant activities. Standard methods and TLC were used to screen the phytochemical composition. The total phenolic and flavonoid content of extracts were assessed by Folin-Ciocalteu and AlCl3 methods, respectively. These extracts were also evaluated for their antioxidant potentials using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonate) (ABTS) assays. Flavonoids, saponins, quinones, sterols/triterpenes and tannins were present in all these species except for I. pulchra where quinones were not found. Gallic acid, caffeic acid, rutin and myricetin in I. colutea; gallic acid, quercitrin, myricetin in I. tinctoria; galangin and myricetin in I. macrocalyx were identified by thin layer chromatography. Among these, I. colutea, I. tinctoria, I. nigritana and I. macrocalyx, which had the highest phenolic content, were also found to possess the best antioxidant activities. The results indicated a good correlation between antioxidant activities and total phenolic content (p<0.05 for FRAP/DPPH and DPPH/ABTS and p<0.01 for FRAP/ABTS). These plants represent promising sources of natural antioxidants and these findings give scientific bases to their ethnopharmacological uses.  相似文献   

3.
To investigate the relationship between reducing sugars and phenolic retention of brown rice after enzymatic extrusion, reducing sugars, total phenolic content, total antioxidant activity, and individual phenolic acids of brown rice extruded with different α-amylase concentrations (0.1%, 0.5%, 1%, w/w) were evaluated. Reducing sugars were produced during enzymatic extrusion and significantly increased with the increasing enzyme concentration. Compared with traditional extrusion, the enzymatic extrusion with 1% amylase significantly increased the phenolic retention, DPPH value, FRAP value, and ABTS value by 22.4%, 19.5%, 14.7%, and 41.5%, respectively. The retention of most free phenolic acids was also increased with the increasing enzyme concentration. Besides, the correlation analysis indicated that the content of reducing sugars was positively correlated with total phenolic content (r = 0.915), DPPH value (r = 0.882), FRAP value (r = 0.861), ABTS value (r = 0.867) and free individual phenolic acids (r = 0.595–0.943) of treated brown rice. These results suggested that reducing sugars might protect phenolic compounds during enzymatic extrusion.  相似文献   

4.

The total phenolics contents, total antioxidant capacity (TAC) and starch hydrolase inhibitory activity of the aqueous extracts of 10 edible plants and the stability of these parameters after the gastric and duodenal digestion in an in vitro model was investigated. The TAC was evaluated using the oxygen radical absorbance capacity (ORAC) assay, ferric reducing antioxidant power (FRAP) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH?) and 2, 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS?+) radical scavenging assays. Characterization and quantification of five polyphenol compounds which were previously identified to be present in all the selected plants were carried out. None of the extracts showed a decrease in the total phenolics content or the ORAC and FRAP values following digestion. None of the quantified phenolic compounds had decreased during any of the digestion phases – an observation which was deemed as beneficial in terms of therapeutic properties. Overall, the parameters analyzed were relatively stable throughout the digestive process in all the extracts.

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5.
为比较不同品种荔枝果皮酚类物质含量、组成及其抗氧化活性差异,用80%甲醇分别提取6个品种荔枝果皮中的酚类物质,测定其总酚和总黄酮含量。采用铁离子还原能力（FRAP）和自由基离子清除能力（ABTS）等方法评价其抗氧化活性。通过高效液相色谱（HPLC）鉴定不同的单体酚并分析其在不同品种荔枝果皮之间的差异。结果表明,不同品种荔枝果皮的酚类物质含量为28.69~68.48 mg/g,不同品种荔枝果皮的酚类物质含量和抗氧化能力存在显著的差异（P<0.05）。酚类物质的含量、FRAP和ABTS抗氧化活性能力均以‘荔枝王’为最高,分别为68.48 mg/g、546.31 μmol/g和511.25 μmol/g。液相色谱结果鉴定出‘糯米糍’中的8种单体酚,而含量相对较高的是A型原花青素三聚体和原花青素A2。研究结果可为荔枝加工废弃物荔枝果皮的开发利用提供理论依据。  相似文献   

6.
采用高效液相色谱法（HPLC）对 4 种黔引迷迭香的多酚成分进行定性和定量分析,并利用 DPPH、ABTS自由基清除能力和铁离子还原能力（FRAP）3 种方法评价多酚成分的抗氧化能力。结果显示 4 种材料均富含类黄酮、酚酸和二萜酚等多酚类化合物,总酚含量介于 4 345.5~5 673.0 mg/100 g 。其中槲皮素、迷迭香酸、阿魏酸、绿原酸和鼠尾草酸是迷迭香最主要的酚类物质。黔引迷迭香 4 号的抗氧化活性最高,利用 DPPH、ABTS 和 FRAP等 3 种方法检测的结果依次为 184.4、290.0、155.6 μmol/g。相关性分析表明,总酚与总抗氧化活性能力显著相关,迷迭香酸对总抗氧化活性能力贡献最大,其次为鼠尾草酸、槲皮素和水杨酸。本研究对于了解黔引迷迭香抗氧化活性成分,以及资源的进一步开发利用具有重要指导意义。  相似文献   

7.

Elicitation is a biotechnological approach to improve phenolic compounds content and antioxidant properties of ready-to-eat functional foods. This study aimed to evaluate the chemical elicitation effects using salicylic acid (SA) and hydrogen peroxide (H2O2) in optimized-germination conditions on seedling vigor, phenolic content, and their antioxidant capacities in vitro and serum and urine of Wistar obese rats. Optimized-germination conditions of 26.5 °C and 178 h produced a 64% of germination and a sprout length of 56 mm. Only, the elicitation with H2O2 (20 mM) enhanced the germination (75%) and H2O2 (10 and 20 mM) the sprout length (69 and 59 mm, respectively). In contrast, both elicitors enhanced phenolic contents, being more significant total phenolic compounds content for SA (1 and 2 mM), up to 65.5–73.5%. SA and H2O2 improved total flavonoids content (36.5–64.1%), ABTS (19.3–61.1%), and DPPH capacities (51–86%), depending on SA and H2O2 concentration, compared with non-elicited chia sprouts. The QUENCHER antioxidant capacities of elicited chia sprouts increased up to three times more than extracts capacities, principally Q-ABTS, which could be attributed to phenolic bounds to dietary fiber. Rats fed with a high-fat and fructose diet (HFFD) and supplemented with chia sprouts, especially 1-mM SA, improve the obesity-related oxidative stress through an increase of antioxidant capacities, using DPPH and ABTS test, on serum (70–118%) and urine samples (80–116%). These results suggest that chia sprouts elicited with 1-mM SA are a source of antioxidant compounds that can be used to decrease obesity related oxidative stress.

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8.
The objective of this study was to characterize the flavonoid compounds found in the different grain parts of common and tartary buckwheat, and to determine the contribution of these flavonoids to the antioxidant properties of buckwheat. Eight flavonoid compounds were quantified and their antioxidant activity determined by FRAP, DPPH, and ABTS assays. Of the flavonoid compounds identified rutin was the most abundant, particularly in tartary buckwheat, in which it comprised approximately 90% of total flavonoid content. Flavan-3-ols were detected in common but not tartary buckwheat, and quercetin was detected only in tartary buckwheat. Flavonoid content—in particular, levels of rutin, orientin, and/or epicatechin gallate—was found to influence the total antioxidant activity of buckwheat. Results from this study indicate that antioxidant activity is not only closely associated with flavonoid content, but that different flavonoids contribute differently to the total antioxidant activity of common and tartary buckwheat.  相似文献   

9.
The effects of three independent variables: solvent polarity, temperature and extraction time on the antioxidant capacity, total phenolic content and phenolic acid composition in extracts obtained from sunflower shells before and after enzymatic treatment were studied. Response surface methodology based on three-level, three-variable Box-Behnken design was used for optimization of extraction parameters and evaluation of their effect on antioxidant capacity and total phenolic content in shell extracts.The average antioxidant capacities of extracts from sunflower shells without enzymatic treatment (368.1-1574.4 μmol TE/100 g) were higher than those for cellulolytic and pectolytic enzymes-treated shells (222.7-1419.0 and 270.7-1570.7 μmol TE/100 g, respectively). The content of total phenolic compounds ranged between 58.2-341.2 mg CGA/100 g, 26.7-277.3 mg CGA/100 g and 51.4-301.5 mg CGA/100 g for extracts obtained from shells without enzyme and treated with cellulolytic and pectolytic enzymes, respectively. Total phenolic content (TPC) in the studied shell extracts correlated significantly (p < 0.0001) positively with their antioxidant capacity determined by the ferric reducing antioxidant power (FRAP) method (r = 0.9275). Results of FRAP, TPC and phenolic acid composition in the studied shell extracts depend on the extraction conditions (solvent polarity, temperature, time), but they are independent on the addition of enzyme solutions. The antioxidant capacity and total phenolic content in the resulting extracts increased with a line in extraction temperature and solvent polarity.  相似文献   

10.
In this work, α-amylase was used to treat oat flour with the intent to release phenolic compounds with known antioxidant properties. After methanol extraction, the amounts of nine beneficial phenolic compounds were measured using HPLC. The antioxidant activities of the extracts were assessed using 2,2′-azinobis (3- ethylbenzothiazoline-6-sulfonic acid) (ABTS)，2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and protein oxidative damage protection assays. Compared with heating-only treated oat flour, that treated with α-amylase showed significant increase of extractable total phenolic content (0.46–1.35 μmol gallic acid equivalents per gram oat), total antioxidant capacity, and an increased ability on the protection of protein from oxidative damage. Heating-only increased caffeic acid and vanillin content by 17 (0.03 vs 0.54 μg/g oat) and 1.8 (0.62 vs 1.11 μg/g oat) folds, but slightly increased the content of other phenols. Excluding heating effect, α-amylase treatment increased gallic acid content by 2.6 folds (0.38 vs 1.38 μg/g oat), caffeic acid content by 2.4 (0.54 vs 1.82 μg/g oat) folds, and other phenols by 1.0–1.8 folds. In conclusion, α-amylase treatment can yield oat products containing more extractable phenolic compounds with increased antioxidant capacity.  相似文献   

11.
The antioxidant capacity of jackfruit (Artocarpus heterophyllus Lam. Fam. Moracae) fruit pulp (JFP) obtained from Western Ghats India was determined by evaluating the scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing power assays and N, N-dimethyl-p-phenylendiamine (DMPD) radical cation decolorization assay. JFP was analyzed for total phenolic content (TPC) and total flavonoids content (TFC). The ethanol and water are the best solvents for the extracting phenols and flavonoids from the JFP. The antioxidant activities of JFP extracts were correlated with the total phenolic and flavonoids content. The results indicated that the jackfruit pulp is one natural source of antioxidant compounds.  相似文献   

12.
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.  相似文献   

13.
In this study polyphenol content, antioxidant activity, lipoxygenase (LOX) and Xanthine Oxidase (XO) inhibitory effects of n-hexane, dichloromethane, ethyl acetate and n-butanol fractions of aqueous acetone extracts from S. alba L., S. acuta Burn f and Cienfuegosia digitata Cav. were investigated. The total phenolics, flavonoids, flavonols and total tannins were determined by spectrophotometric methods using Folin-ciocalteu, AlCl3 reagents and tannic acid, respectively. The antioxidant potential was evaluated using three methods: inhibition of free radical 2,2-diphenyl-1-picrylhydramzyl (DPPH), ABTS radical cation decolorization assay and Iron (III) to iron (II) reduction activity (FRAP). For enzymatic activity, lipoxygenase and xanthine oxidase inhibitory activities were used. This study shows a relationship between polyphenol contents, antioxidant and enzymatic activities. Present results showed that ethyl acetate and dichloromethane fractions elicit the highest polyphenol content, antioxidant and enzymatic activities.  相似文献   

14.
分析了我国不同产区不同品种亚麻籽的组成及体外抗氧化特性。结果表明,除基本组成成分外,不同品种亚麻籽主要活性组分含量和体外抗氧化活性具有显著差异。α-亚麻酸、木酚素、总酚酸、黄酮、生育酚、植物甾醇含量范围分别为33.42%~59.74%,120~918 mg/100g,209~491 mg/100g,33.04~75.63 mg/100g,8.68~20.75 mg/100g,340~596 mg/100g。亚麻籽提取物DPPH值和FRAP值分别为4 357~8 146 μmol Trolox/100g, 8 289~15058 μmol Trolox/100g。此外,不同品种亚麻籽抗营养因子生氰糖苷含量差异较为显著(5.57~11.34 mg HCN/100g)。相关性分析结果表明,亚麻籽提取物体外抗氧化活性与木酚素、总酚酸和黄酮含量具有显著相关性（p<0.05）。主成分分析和聚类分析结果表明,亚麻籽主要酚类化合物及其抗氧化活性主要依赖于亚麻籽品种特性,而非种植区域。  相似文献   

15.
Red arils of Pithecellobium dulce fruit, commonly known as guamuchil, show high antioxidant (AOx) and α-glucosidase inhibitory (IαG) activities, which have been mainly associated with the content of unknown anthocyanins. In this study, the AOx (i.e., DPPH and ABTS as Trolox equivalents, μmol TE/g) and IαG (as half-maximal inhibitory concentration, IC50, mg/mL) activities of the anthocyanin-rich fraction (ARF) obtained from red arils were contrasted with those of the methanol extract (ME), and the main ARF anthocyanins were characterized by HPLC-DAD-ESI-MS, GC-MS and 1H-NMR. The AOx and IαG values of the ARF (DPPH?=?597.8; ABTS?=?884.01; IαG?=?0.06) were better than those of the ME (DPPH?=?41.5; ABTS?=?142.3; IαG?=?17.5); remarkably, the ARF IαG value was about 42 times lower than that of acarbose. The main anthocyanins in ARF were pelargonidin 3-O-glucoside and cyanidin 3-O-glucoside. Thus, the consumption of red P. dulce arils could provide health benefits for prevention/treatment of chronic degenerative diseases such as diabetes.  相似文献   

16.
Among Vaccinium species, blueberries (Vaccinium myrtillus L.) and lingonberries (Vaccinium vitis-idaea) are popular in the human diet. In this study, total phenolic, total flavonoid and total monomeric anthocyanin contents in the ethanol-water extracts of blueberry and lingonberry fruits grown wild in the forests in the central region of Poland were assayed. Antioxidant activities of the extracts from each plant were also evaluated for scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and reducing power by cupric reducing antioxidant capacity (CUPRAC) method. Total phenolics in the blueberry extracts ranged from 4.58 to 5.28 mg GAE CE/g fw. The extracts from lingonberry fruits contained higher total contents of phenolic compounds (5.82–7.60 mg GAE/g fw) as well as total flavonoids (5.22–6.47 μmol CE/g fw) than those from blueberries (3.74–4.18 μmol CE/g fw). For the total monomeric anthocyanin contents, the blueberry extracts presented significantly higher values (3.01–3.93 mg cyanidin-3-glucoside (C3G) equivalent/g fw) in comparison to the lingonberry extracts (0.32–0.47). Blueberry extracts exhibited higher antioxidant activity measured by both assays in comparison to lingonberry extracts. Water extracts from fresh and dried fruits also exhibited significant antioxidant activities for both types of berries. Considering the health benefits that have been associated with polyphenolic consumption, these fruits could appear as a good source of this group of phytochemical compounds for their direct consumption or their use as ingredients for the design of new food products or food supplements.  相似文献   

17.
张旭  李静  徐静 《热带作物学报》2017,38(5):849-853
植物抗氧化研究对寻找高效率、低毒性天然抗氧化剂具有重要的指导意义。以在海南分布较广的红树林植物海莲进行抗氧化活性研究,以期对海莲开发利用的可能性提供理论依据。采用清除DPPH自由基和清除ABTS自由基对海莲不同部位———根、茎、叶、花的乙酸乙酯提取物进行抗氧化能力评价,采用比色法和福林酚法测定总黄酮和总酚含量。结果显示,海莲茎的提取物在4个部位中抗氧化活性最好,清除二者的IC50分别为(0.234±0.053)mg/m L和(0.196±0.080)mg/m L,海莲中酚类物质含量较大,4个部位中茎的总酚含量最多,含量为13.2 mg。说明海莲各部位均显示出了较好的抗氧化能力,具有较好的开发潜力。  相似文献   

18.
为研究铁观音提取物和荆芥提取物联用在抗氧化方面的协同作用,采用水浸提法分别萃取铁观音和荆芥得其抗氧化活性成分。以芦丁为标准品检测两种提取物类黄酮含量,其中铁观音提取物为15.13 mg/g,荆芥提取物为0.87 mg/g;以没食子酸为标准品检测两种提取物的总酚含量,其中铁观音水提物为50.87μg/mg,荆芥水提物为47.40μg/mg。用2,2-二苯基-1-苦基肼(DPPH)和2,2'-二氮-双(3-乙基苯并噻唑-6-磺酸)(ABTS)法评估两种提取物联合应用时的抗氧化活性,结果表明,在较低浓度时,铁观音与荆芥提取物联用具有协同增强抗氧化作用。  相似文献   

19.
Two locally grown wheat species named Triticum aestivum L. and Triticum vulgare L. were studied for their phytochemical contents and their biological activities. T. vulgare presented the highest amounts of total phenolic compounds and ascorbic acids while T. aestivum was found to be rich in flavonoids, flavonols, proanthocynidins and ortho-diphenols. Eleven carotenoids were identified in T. vulgare where the most dominant compounds belongs to α-carotene and its derivatives while T. aestivum presented seven carotenoids. This later presented the highest DPPH radical scavenging activity and exhibited a strong reducing power in FRAP, phosphomolybdenum, hydrogen peroxide and reducing power assays. T. vulgare extract was found to be effective in metal chelating power and in scavenging nitric oxide radical. No significant differences in scavenging ABTS and hydroxyl radicals were noted between the two wheat species. T. aestivum inhibited xanthine oxidase and ROS production and showed the best cytotoxic effect while T. vulgare extract exhibited anti-calpain activity.  相似文献   

20.
In this study, the content of soluble, free forms of phenolic compounds (total phenolics, flavonoids, PVPP (polyvinylpolypyrrolidone) bound phenolics, proanthocyanidins and phenolic acids), as well as the content of carotenoids and tocopherols, were determined in whole grains of bread and durum wheat, rye, hull-less barley and hull-less oat, each represented with four genotypes. Antioxidant activity was evaluated as radical scavenging activity with DPPH (2,2-diphenyl-1-picrylhydrazyl) reagent, as well as by hydrogen transfer reaction (reduction power) based on the reduction of Fe3+. Generally, a considerable variation in antioxidant activities and phytochemical contents was observed between the cereals. Remarkably higher DPPH radical scavenging ability and reducing power were detected in hull-less barley, followed by rye and hull-less oat and durum and bread wheat, indicating that small grain species have different major antioxidants with different properties. Hull-less barley had the highest content of total free phenols, flavonoids, PVPP bound phenolics and contained flavan-3-ols, not found in other species. Hull-less oat had the highest content of tocopherols, very high content of yellow pigments and PVPP bound phenolics. Ferulic acid was the major free phenolic acid in small grain cereals tested. The relationship between the content of soluble phenols, as well as reducing power and DPPH• scavenging activity are also considered.  相似文献   

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