草莓、黑莓、蓝莓中多酚类物质及其抗氧化活性研究

研究草莓、黑莓、蓝莓3种小浆果的总酚、总黄酮、原花青素含量及其总抗氧化能力。结果表明:蓝莓全果的总酚、总黄酮、原花青素含量在所测3种浆果全果中最高,分别为9.44mg没食子酸/g干质量、36.08mg芦丁/g干质量、24.38mg儿茶素/g干质量;其总抗氧化能力也最强,达14.98mmol Trolox/100g干质量。草莓的总酚、总黄酮、原花青素含量则最低,抗氧化能力也最弱。此外,3种浆果果渣中的总酚、总黄酮、原花青素含量以及总抗氧化能力均高于全果和果汁,即果渣>全果>果汁。总酚含量、总黄酮含量以及原花青素含量与总抗氧化能力之间的相关性分析表明,总酚含量与总抗氧化能力之间存在显著线性相关,相关系数r达到0.9704,表明酚类物质是其抗氧化作用的主要物质基础。     

加工工艺对豆豉抗氧化能力的影响

本文以黄豆为原材料制作豆豉，测定了浸泡、蒸煮、曲霉发酵、加盐后豆豉50％乙醇提取物清除DPPH（2，2-diphenyl-1-picrylhydrazyl hydrate）及ABTS[2，2’-azinobis-（3-ethylbenzthiazoline-6-sulfonicacid）]自由基能力，评价了加工工艺对豆豉抗氧化能力的影响。大豆经过浸泡、蒸煮后，其提取物抗氧化能力变化不大。曲霉发酵过程中，豆豉的抗氧化能力随发酵时间的延长而增大。后发酵过程中，豆豉的抗氧化能力持续增大，盐对豆豉的抗氧化能力有影响，发酵相同时间的豆豉，抗氧化能力随盐含量的增大而下降。     

不同品种和成熟度树莓和黑莓果实的氧化和抗氧化活性比较

采用多变量分析方法探讨不同品种和成熟度对树莓和黑莓果实氧化和抗氧化活性的影响。单因素方差分析表明,“三冠王”黑莓果实的谷胱甘肽(GSH)、总酚和总黄酮含量均显著高于其他品种,且随果实成熟度的升高,总抗氧化能力下降。品种和成熟度对树莓和黑莓果实的GSH、总酚和丙二醛(MDA)含量,以及清除羟自由基( ·OH)能力的影响更为显著。主成分分析表明,相比于成熟度而言,品种对树莓的抗氧化能力影响更为显著。相关性分析和偏最小二乘回归分析表明,过氧化氢与MDA、GSH和清除超氧阴离子自由基(O2－ ·)均呈正相关性,而总酚与总抗氧化能力、清除 ·OH能力、清除DPPH自由基能力呈正相关性;通径分析表明,树莓和黑莓果实的总酚含量和总黄酮对H2O2含量的直接效应最强。     

覆盆子黄酮抗氧化活性研究

经分离提取后,对覆盆子黄酮提取物的体外抗氧化活性进行了研究,结果表明,覆盆子黄酮提取物对OH、H2O2、DPPH均有不同程度的清除作用,清除率强弱顺序为：纯化后的覆盆子黄酮〉覆盆子黄酮二次萃取物〉覆盆子黄酮粗提物;覆盆子黄酮提取物对花生油的自动氧化也有明显的抑制作用,0．2％覆盆子黄酮提取物在油脂中的添加量好于0．02％的BHT。     

红树莓花色苷的提取及抗氧化活性研究

采用酸化乙醇法提取红树莓中的花色苷,通过正交试验确定花色苷提取的最佳条件,同时对红树莓花色苷提取物的抗氧化活性进行研究。结果表明,以盐酸酸化的80%乙醇溶液(pH3)按1:20(g/mL)的料液比在60℃提取红树莓1.5h,此条件下,鲜果中花色苷提取量达0.625mg/g。在实验范围内,红树莓花色苷提取物的还原能力、对羟自由基和超氧阴离子自由基的抑制率均随质量浓度的升高而增加。红树莓花色苷提取物抑制羟自由基和超氧阴离子自由基的半数有效浓度(EC50)分别为0.175mg/mL和0.699mg/mL,说明红树莓花色苷提取物抑制羟自由基比抑制超氧阴离子自由基的能力强。     

红树莓叶片生长代谢过程中酚类物质含量及抗氧化酶活性分析

为探究红树莓叶片生长代谢过程中酚类物质含量与抗氧化酶活性的变化规律,以‘海尔特兹’和‘秋福’红树莓叶片为材料,对其总黄酮、7种酚类物质和3种抗氧化酶活性的变化规律进行比较分析。结果表明：从5月到12月,两品种红树莓上、中、下部叶片的鞣花酸含量、过氧化物酶（peroxidase,POD）活性在生长代谢过程中均呈双峰曲线,水杨酸含量在生长代谢过程中均呈下降趋势,阿魏酸、儿茶素、表儿茶素、芦丁、总黄酮含量在生长代谢过程中均呈单峰曲线,超氧化物歧化酶（superoxide dismutase,SOD）活性一直处于较高水平,过氧化氢酶（catalase,CAT）活性呈先下降再上升又下降的变化趋势;两品种红树莓上部叶片的咖啡酸含量均呈下降趋势,中部和下部叶片均呈单峰曲线。红树莓叶片中的酚类物质含量和抗氧化酶活性因生长代谢过程而异。其中,水杨酸、阿魏酸、鞣花酸、表儿茶素含量最高的时期依次是‘秋福’的5月份上部叶片、6月份上部叶片、7月份中部叶片、7月份上部叶片,依次为59.33 mg/100 g、158.18 mg/100 g、250.84 mg/g、350.04 mg/100 g;芦丁、咖啡酸、儿...     

透骨草不同极性成分抗氧化活性研究

研究透骨草不同极性成分的抗氧化活性,探讨作为天然食用抗氧化剂开发的可行性。采用ABTS、DPPH自由基及还原性反应体系,利用分光光度法测定透骨草的总提物、乙酸乙酯层、正丁醇层及水层提取物在不同浓度下的抗氧化能力。透骨草的不同极性成分对DPPH、ABTS+自由基均具有较强的清除能力及还原能力,其中正丁醇层提取物的抗氧化能力最强。还原性测定中,在浓度为3.2mg/mL时,正丁醇层提取物的吸光度值为2.537,表明正丁醇层提取物的还原能力强,抗氧化作用好。DPPH法测定中,正丁醇层提取物对DPPH自由基的最大清除率为97.37%。ABTS法测定中,正丁醇层提取物对ABTS+自由基的最大清除率为99.56%,与同浓度Vc的清除率接近。结论:透骨草具有较好的抗氧化能力,可进一步研究开发成天然食用抗氧化剂。     

Antioxidant Activity and Total Phenolic Content in Some Cereals and Legumes

The antioxidant activities and total phenolic content of 4 cereals (buckwheat, wheat germ, barley, and rye) and 4 legume seeds (lentils, mungo bean, red kidney bean, and soy bean) were determined. The total phenolic content (TPC), determined according to the Folin-Ciocalteu method, for cereal samples varied from 13.2 to 50.7 mg Gallic acid equivalent/g of dried extract, while for legume samples varied from 17.0 to 21.9 mg Gallic acid equivalent/g of dried extract. Antioxidant activities were comparatively assessed by 2,2-diphenyl-1- picrylhydrazyl (DPPH) scavenging capacity, ferric ion-reducing antioxidant power (FRAP) and the thiobarbituric acid (TBA) method. The tested plant extracts showed promising antioxidant and free radical scavenging activity, thus justifying their traditional use. Among examined cereals all the applied methods, except TBA method, have shown that buckwheat have the highest antioxidant activity, while among examined legumes results varied depending on the method used.     

黑莓花色苷的超声波提取与抗氧化性活性研究

为确定黑莓花色苷超声波提取的最佳工艺条件,以花色苷得率为考察指标,利用超声波处理,通过单因素和正交试验优化最佳提取工艺条件,并对黑莓花色苷的抗氧化活性进行初步研究。结果表明：黑莓花色苷的最佳提取工艺条件为：超声时间35min、75%乙醇作溶剂、料液比1:20(g/mL)、黑莓花色苷的得率为0.365mg/g。在相同质量浓度条件下,黑莓花色苷溶液还原力明显高于VC溶液,并具有较强抑制Cu2+诱导的低密度脂蛋白氧化修饰作用。     

Effect of Freezing and Frozen Storage on Phenolic Compounds of Raspberry and Blackberry Cultivars

The phenolic compounds in raspberry and blackberry cultivars grown in Turkey were determined by liquid chromatography–mass spectrometry (MS)/MS in fresh, just-frozen, and stored fruits at −22 °C for 6 months period. The major phenolic compounds in water extracted samples were ellagic acid (1,350.36–727.9 mg/kg fresh fruit), ferulic acid (820.78–338.27 mg/kg fresh fruit), caffeic acid (754.85–202.78 mg/kg fresh fruit), p-coumaric acid (361.68–142.63 mg/kg fresh fruit), p-hydroxybenzoic acid (534.20–233.29 mg/kg fresh fruit), and quercetin (46.97–27.31 mg/kg fresh fruit) in raspberry and ellagic acid (1,828.07–1,555.13 mg/kg fresh fruit), ferulic acid (757.69–413.82 mg/kg fresh fruit), caffeic acid (736.85–337.89 mg/kg fresh fruit), p-coumaric acid (877.45–287.15 mg/kg fresh fruit), and quercetin (74.69–56.78 mg/kg fresh fruit) in blackberry. The varietal differences in the phenolic compound contents were larger among the blackberry cultivars (from 1,828.07 to 56.78 mg/kg fresh fruit) than among the raspberry cultivars (1,350.36 to 27.31 mg/kg fresh fruit). A significant decrease was observed in the content of p-hydroxybenzoic acid (from 534.20 to 114.30 mg/kg; Aksu Kırmızısı) and the least decrease was in the content of caffeic acid (from 545.42 to 530.91 mg/kg; Heritage) in raspberry cultivars. On the other hand, ferulic acid (from 475.16 to 113.33 mg/kg) decreased significantly in blackberry (Bursa 2) after storage for 6 months.     

Phenolic Compounds,Antioxidant Activity,and Medium Chain Fatty Acids Profiles of Coconut Water and Meat at Different Maturity Stages

Coconut is grown in tropical and subtropical areas worldwide. The endosperm (water and meat) is consumed and processed in different forms. This study investigated the antioxidant activities and identified the phenolic compounds existing in the water and meat of coconut fruits at three different maturity stages, i.e., 180, 190, and 225 days after pollination from two planting areas in Thailand. Total phenolic content and antioxidant activity indices increased as the coconut matured from 180 to 190 days after pollination and then decreased or remained unchanged at 225 days after pollination. Catechin and salicylic acid were the major phenolic compounds found in the water, while gallic, caffeic, salicylic, and p-coumaric acids were found in the meat. The fat content of the meat increased significantly with maturity stage. Medium chain fatty acids profiles were also analyzed. The results are important for producers, processors, and consumers to realize an optimal quality and functionality of coconut water and meat when used for specific purposes.     

不同豇豆中酚类含量与抗氧化活性

为深入了解豇豆的营养价值,以11个不同品种的豇豆样品为原料,对其总酚含量、总黄酮含量及抗氧化活性(总还原能力、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除能力、·OH清除能力)进行分析,并讨论酚类物质含量及抗氧化活性的相关性。结果表明,不同品种的豇豆酚类物质含量和抗氧化活性差异显著。在测定的样品中,新杂1号表现出最高的总酚含量(5.59 mg GAE/g)、总黄酮含量(4.12 mg CAE/g)及抗氧化活性(总还原能力和DPPH自由基清除能力);豇豆中总酚含量、总黄酮含量与总还原能力、DPPH自由基清除能力之间有极显著相关性(P0.01),与·OH清除能力之间没有显著相关性。     

15 种柑橘果实主要酚类物质的体外抗氧化活性比较

为了明确柑橘果实主要酚类物质单体的抗氧化活性差异,利用1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）法、2,2’-联氮-二（3-乙基-苯并噻唑-6-磺酸）二铵盐（2,2’-azino-bis（3-ethylbenzthiozoline-6）-sulphonic acid,ABTS）法、铁离子还原（ferric reducing/antioxidant power,FRAP）法3 种离线法,以及两种在线高效液相色谱-DPPH/ABTS（high performance liquid chromatography-DPPH/ABTS,HPLC-DPPH/ABTS）柱后衍生系统联用技术分别对15 种柑橘果实主要酚类物质单体的抗氧化活性进行测定和比较分析。结果表明：抗氧化活性综合（antioxidant potency composite,APC）指数可有效反应各单体的抗氧化活性,柑橘果实15 种主要酚类物质抗氧化活性明显不同,4 种酚酸的抗氧化活性最强,依次为：没食子酸（92.32%）＞咖啡酸（85.29%）＞绿原酸（69.75%）＞阿魏酸（50.97%）。圣草酚（39.38%）、圣草次苷（39.36%）和芦丁（27.42%）的抗氧化活性中等,橙皮素、柚皮素、地奥司明、橙皮苷、川陈皮素、甜橙黄酮、柚皮苷和橘皮素的抗氧化活性较小（＜5%）。酚羟基的糖基化或甲基化会都降低柑橘酚类物质的自由基清除能力,酚羟基数目越多,抗氧化活性越强。     

Phenolic Profiles and Total Antioxidant Capacity of Marketed Beers in Serbia

The aim of this research was to determine the total phenolic and flavonoid contents as well as to measure antioxidant activity of 24 different commercial beers consumed in Serbia. The major phenolic acids (gallic acid, protocatechuic acid, 4-hydroxybenzoic acid, 2,5-dihydroxybenzoic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, sinapic acid, salicylic), (+)-catechin, and (-)-epicatechin were also determined by high pressure liquid chromatography method using a photodiode array detector. Gallic acid, ferulic acid, and protocatechuic acid are the most abundant phenolic acids in all samples, followed by (+)-catechin. The total phenolic content was determined using the Folin-Ciocalteu assay. The total flavonoids were measured using spectrophotometrics as the aluminum chloride assay. The results showed that the highest total phenolic and flavonoid contents were established in dark and light beer samples. 2,2-Diphenyl-1-picrylhidrazyl radical scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical cation scavenging activity, and ferric reducing/antioxidant power were used to assess the antioxidant potential of beers. These assays, based on different chemical mechanisms, were selected to take into account the wide variety and range of action of antioxidant compounds present in selected beer samples. All beers showed antioxidant power, but a wide range of antioxidant capacities was observed. Statistical differences between ferric reducing-antioxidant power and the other two antioxidant capacity assays were confirmed. This study will be useful for the appraisal of phenolic profile and antioxidant activities of various beers, and it will also be of interest for people who like drinking this beverage.     

覆盆子不同极性溶剂提取物的抗氧化活性比较

为比较覆盆子不同极性溶剂提取物的抗氧化活性,分别用正丁醇、乙酸乙酯、丙酮、去离子水、50％乙醇和石油醚进行萃取,测定各提取物总多酚和总黄酮的含量,并通过清除DPPH自由基、ABTS自由基、羟基自由基和总还原能力4种体系对其体外抗氧化活性进行评价.结果显示,乙酸乙酯提取物中总多酚含量最高,50％乙醇提取物中总黄酮含量最高...     

外源添加物质对黑莓清汁花色苷稳定性和抗氧化活性的影响

本文研究了咖啡酸、阿魏酸、单宁酸、黄芩素、茶多酚、没食子酸、原儿茶酸、芦丁等8种外源辅色素对黑莓清汁花色苷辅色效果、热稳定性、光稳定性和体外抗氧化活性的影响。结果表明:咖啡酸、原儿茶酸、茶多酚、没食子酸、单宁酸对黑莓清汁花色苷的辅色效果影响较显著(p<0.05),最适浓度为0.1 mmol/L,而芦丁的最佳辅色浓度为0.4 mmol/L;实验所选辅色素能够在一定程度上提高黑莓清汁花色苷的热稳定性,其中没食子酸、阿魏酸、咖啡酸对其影响效果显著(p<0.05),分别使黑莓清汁花色苷的热降解半衰期延长了6.06、2.07和1.39倍。此外,原儿茶酸、阿魏酸、芦丁能够显著提高黑莓清汁花色苷的光稳定性、DPPH自由基清除能力和总还原力(p<0.05);没食子酸和单宁酸的辅色作用降低了黑莓清汁花色苷的光稳定性。黄芩素、阿魏酸、咖啡酸、芦丁等外源物质可作为黑莓清汁花色苷有效的辅色素。     

黑莓籽油脂肪酸成分及抗氧化活性研究

采用超声波辅助提取从黑莓籽中提取籽油,用GC/MS方法对籽油脂肪酸成分进行了分析,并通过测定籽油清除DPPH自由基的能力对黑莓籽油的抗氧化能力进行了评价。结果表明:黑莓籽油中不饱和脂肪酸占68.48%,对DPPH自由基清除能力研究表明1 mL黑莓籽油的抗氧化能力相当于2.092 mg抗坏血酸,具有良好的抗氧化能力。     

Total Antioxidant Activity and Total Phenolic Contents in Different Turkish Eggplant (Solanum Melongena L.) Cultivars

In this study, total water soluble antioxidant activity and phenolic content of 26 eggplant ( Solanum melongena L. ) cultivars were investigated. Total water soluble antioxidant activity of the cultivars varied from 2664 to 8247 μmolTrolox/kg, which is a 3.1-fold difference. Cultivars also showed significant variation for total phenolic contents ranging from 615 to 1376 mg/kg, a 2.2-fold difference. The two traits were significantly correlated and results of this study suggested that breeders can use the information to develop eggplant cultivars with high antioxidant activity.     

红葡萄酒、啤酒和白酒抗氧化作用研究

采用二苯苦味酰肼(2,2-Diphenyl-1-picryl-hydrazyl radical,DPPH)法、ABTS(3-ethyl benzot hiazoline-6-sulfonic acid)法、邻苯三酚自氧化法及羟自由基抑制法对红葡萄酒、啤酒和白酒的清除自由基活性进行比较.结果表明,红葡萄酒对DPPH自由基、ABTS·+自由基、超氧阴离子自由基的清除率分别为73.05%、64.37%和50.08%.啤酒对上述3种自由基的清除率分别为2.31%、1.40%和4.03%.白酒对这3种自由基的清除率分别为0.19%、0.04%和0.11%.红葡萄酒、啤酒和白酒对羟自由基的抑制率分别是43.39%、4.99%和1.24%.结果显示,葡萄酒对DPPH自由基、ABTSS·+自由基、超氧阴离子自由基、羟自由基的清除作用最强,啤酒其次,白酒最弱.     

Antioxidant Activity and Phenolic Content of Persimmon Peel Extracted with Different Levels of Ethanol

In this study, antioxidant potentials of persimmon peel extracted with different levels of ethanol (0 [DW], 50, 70, and 99%) were screened for their antioxidant activity at various concentrations. The persimmon peel extracted by 70% ethanol inhibited 89.82% of 1,1-diphenyl-2-picrylhydrazyl radical at 0.5 mg/mL and had β-carotene bleaching inhibition activity at values of 91.26%. superoxide dismutase-like activity and reducing power had the highest in persimmon peel extracted by 70% ethanol each at 0.5 mg/mL and 1 mg/mL and the lowest persimmon peel extracted by distilled water. These results provided that persimmon peel extracted by 70% ethanol could be the most effective as a natural antioxidant in food industry.