Antiradical Activity and Ferric Reducing Antioxidant Power of <i>Pleurotus pulmonarius</i>, <i>Pleurotus floridanus</i>and <i>Pleurotus sajor</i>-<i>caju</i>Formulations Extracts <i>in Vitro</i>

Edible mushrooms, known for many years and considered as functional foods, contain a wide variety of biomolecules with nutritional and medicinal properties. Pleurotus species, especially Pleurotus pulmonarius, Pleurotus floridanus and Pleurotus sajor-caju are the most commonly consumed in Cameroon. The present work aims to study the “in vitro” antiradical activity and ferric reducing antioxidant power of extracts of formulations of these three species. Mushrooms were harvested in two mycicultures from Cameroon, then dried and crushed finely to obtain powders. In well-defined proportions, ten different formulations were made and their aqueous, ethanol and hydroethanol extracts prepared. These were used to determine total phenolic content by using Folin-Ciocalteu reagent method, the antioxidant activity determined by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activity and ferric-reducing antioxidant power (FRAP) assays, with vitamin C (ascorbic acid) as standard. The results obtained from the ten formulations, including thirty extracts, showed that all the extracts had quite significant ferric reducing power at C = 1 mg/ml, (7.35 - 26.02 mg EAA/g). They also had good percentages of DPPH radical inhibition at C = 25 mg/ml (60.40% - 77.72%) and a significant polyphenol content at C = 100 mg/ml (13.73 - 21.15 mg CE/g). The aqueous extracts had the best activities compared to the standard. In addition, a strong positive linear correlation exists between polyphenol content and the scavenging property (R2 = 0.9063;p = 0.0003) also with the ferric reducing test (R2 = 0.9253;p = 0.0001);suggesting the responsibility of these compounds for these activities. This study suggests that these mushrooms may be used as a natural source of potential antioxidants for food supplements and their consumption is strongly recommended for their beneficial effects on health through, the protection of the human body against the oxidative damage involved in the occurrence of many chronic diseases.

Plasma protein oxidation and total antioxidant power in premenstrual syndrome

Objective:To explore whether oxidative stress has any role in premenstrual syndrome(PMS). Methods:Female volunteers suffering from PMS,in the age group of 20-24 years were compared to their asymptomatic normomennorhoeic counterparts in follicular phase and late luteal phase for ferric reducing antioxidant power of plasma(FRAP),plasma protein thiols(PPT) and protein carbonyls(PPC) levels.Results:There was no significant change in FRAP and PPC levels in controls and PMS groups but PPT decreased significantly in luteal phase of PMS(P【 0.05) when compared to follicular phase.Conclusions:Estrogen and progesterone,might be responsible for a healthy antioxidant profile in PMS.However,a marked decrease in PPT in luteal phase of PMS group may be due to pro-oxidant nature of estrogen-active in this phase of PMS leading to consumption of the sacrificial antioxidant-protein thiol.

Total phenols, flavonoids, and procyanidins levels and total antioxidant activity of different Korean pine(Pinus koraiensis) varieties

Total phenols,flavonoids,procyanidins,and total antioxidant capacity,measured with ferric reducing antioxidant power,radical scavenging capacity,and oxygen radical absorption capacity assays were first evaluated in the extracts of the shells,skins and kernels of 10 varieties of Pinus koraiensis.Results indicate that these varieties had strong radical scavenging capacities,ferric reducing antioxidant power and oxygen radical absorption capacities.Phenolic,flavonoid and procyanidin values ranged from 138.6(#3 kernel)to 518.6(#10 shell)mg GAE/g,from 23.3(#2 kernel)to 70.8(#5 skin)mg RE/g,from 2.5(#2 kernel)to 142.1(#7 skin)mg CE/g,respectively.Radical scavenging capacity and ferric reducing antioxidant power values were positively correlated to the polyphenol contents which play a major role in antioxidant properties.The varieties may be divided into two groups by cluster analysis and the variables being measured.These results will be useful for breeding varieties and guiding their production.

Antioxidant and Phenolic Content of Nuts, Oil Seeds, Milk and Milk Products Commonly Consumed in India

Food provides not only essential nutrients required for life, but also bioactive compounds usefull to maintan good health and disease prevention. Abundant epidemiological evidences suggest that consumption of food rich in antioxi-dants (non-nutritional components) can prevent degenerative diseases. A total of 26 commonly consumed nuts, oil seeds, edible oils, milk and milk products were chosen for the study. Considering the fact that antioxidant content (AOC) and phenolic contents (PC) of these foods was not established systematically in Indian context. Therefore, we have assessed and correlated the AOC and PC, an important antioxidant constituents of plant foods. AOC was assessed by DPPH (2, 2-Diphenyl-1-picryl hydrazyl) scavenging activity and FRAP (Ferric reducing antioxidant power) methods and phenolic content (PC), using Folin-Ciocalteu reagent. Among the nuts and oil seeds arecanut had the highest phenolic and antioxidant content 10841, 4220341 mg/100g respectively. In milk, edible oils and sugars the values ranged from 336 -11674 mg/100g. Jaggery had the highest PC and AOC among the foods studied . Although AOC and PC showed wide variation among the foods, AOC was correlated significantly with PC. Indeed the ‘r’ value between PC and AOC (DPPH and FRAP) was 0.99 (p < 0.01) among the nuts and oil seeds, while in milk, milk products and sugars, the “r” values ranged from 0.93 and 0.99 (p < 0.01) respectively. The overall results indicate that the phenolic compounds may be significant contributors to the AOC of the foods studied.

Antioxidant Activity of 50 Traditional Chinese Medicinal Materials Varies with Total Phenolics

This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent experiments. Folin-Cicolteau phenol reagent and a colorimetric method were used to determine the total phenolic content of the selected herbs. The result showed that total phenolic content of those herbs ranged from 2 to 185 mg/g. In antioxidant assay, the ferric reducing/antioxidant power (FRAP) values ranged from 2 to 134 mg GAE/g;the IC50 values of DPPH?·, ·OH and ?scavenging were in the range of 0.06 - 5.50 mg/mL, 0.017 - 0.636 mg/mL and 0.050 - 0.681 mg/mL respectively. Flos caryophylli was the exceptant in the ?scavenging assay because there was no linear relation between the concentration and the scavenging percentage. Compared to gallic acid, ascorbic acid and butylated hydroxytoluene (BHT) in antioxidant assay as positive control, the most potential antioxidant herbs were Cacumen platycladi, Radix et Rhizoma rhei, Rhizoma rhodiolae crenulatae, and Rhizoma sanguisorbae with considerable content of phenolics. Especially, a positive and significant correlation was found between the total phenolic content and FRAP value or DPPH· scavenging percentage.

<i>In Vitro</i>Analysis of the Antioxidant Effect of Allspice

Antioxidants are free radical scavengers found in spices which may play a significant role in preventing cell death. Allspice is a dried unripe berry obtained from the Pimento dioica plant that may have antioxidant potential. The objective of this study was to determine the total phenolic, flavonoid content and antioxidant capacity of allspice using selected assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Potential (FRAP) and Trolox Equivalent Antioxidant Capacity (TEAC), Nitric Oxide (NO) and Oxygen Reducing Antioxidant Capacity (ORAC). Total phenolic and flavonoid contents of allspice were determined using both water and methanol extraction. A comparison of antioxidant activity of water and methanol extracts of allspice was conducted using the different assays (DPPH, TEAC, NO, ORAC and FRAP). The total phenolic content (6.9%), NO scavenging (38.8%) and ORAC (35.1%) activity were higher in methanol compared to water extracts of allspice while flavonoids (57%), FRAP (11.2%), and TEAC (1.82%) were higher in water extracts compared to methanol extracts of allspice. The total phenolic and flavonoid content were higher in methanol extracts compared to water extracts of allspice. The IC50 (DPPH), FRAP and TEAC, NO scavenging and ORAC activity were higher in methanol extracts compared to water extracts of allspice. Total flavonoid content, FRAP and TEAC, NO scavenging and ORAC were significantly higher (p ≤ 0.5) in methanol extracts compared to water extracts of allspice. This shows that allspice has antioxidant potential and that the method of extraction can play a crucial role on the number of phytochemicals extracted from the plant. Utilization of allspice in food products may provide additional functional properties.

Antioxidant Activity Evaluation in a Series of Heterocyclic Compounds Derived from 1,8-Diaminonaphthalene

From (2,3-dihydro-1H-perimidin-2-yl)-phenyl, the substitution of OH group in ortho or para position on the phenyl ring, allows us to synthesize the studied compounds. These three compounds have been characterized by conventional spectroscopic methods (NMR and MS). The interest of this work is to review the antioxidant activity of our compounds. The antioxidant activity screening carried out according to FRAP and DPPH methods revealed significant anti-free radical properties for compounds 1 and 2 even at low concentrations. In contrast to the compound 2, compound 3 for which the OH group is substituted in para position has the lowest activity in both cases. Therefore the para position seems to be the least sensitive position to increase the antioxidant activity of this pharmacophore.

铁离子还原法(FRAP)测定中国被毛孢菌丝体提取物抗氧化活性

FRAP法测定了6批人工培养中国被毛孢(Hirsutella sinensis)菌丝体热水和乙醇提取物的抗氧化活性.结果表明:1 mg/mL人工培养中国被毛孢丝体水提物和乙醇提取物的平均抗氧化活性分别相当于(327.5±42.1)μmol/mL Fe2+和(107.1±13.5)μmol/mL Fe2+;方法学研究显示重现性为3.8%;精密度为3.1%;可靠性相关系数R2为1.0000;回收率分别为(105.4±5.8)%(水提物)和(104.2±8.8)%(醇提物);该方法在30 min内结果的变异系数为3.0%.这些结果表明:中国被毛孢菌丝体热水和乙醇提取物均具有一定的抗氧化活性,用FRAP法测定具有良好的重现性、精密度、可靠性、回收率和稳定性.

可食用植物来源外泌样纳米颗粒体外抗氧化能力及其对过氧化氢诱导PC12细胞氧化损伤的保护作用

目的:探讨生姜、青椒、大蒜、蘑菇、柠檬、山药、葡萄、番茄、西兰花和洋葱10种可食用植物来源外泌样纳米颗粒(ELNs)的体外抗氧化能力及其对过氧化氢诱导PC12细胞氧化损伤的保护作用,为深入研究ELNs提供依据。方法:将PC12细胞分为对照组、外泌体组、过氧化氢组和过氧化氢+ELNs组。高速差速离心法分离提取10种ELNs,采用二苯基苦基苯肼(DPPH)自由基清除体系、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二按盐(ABTS)阳离子自由基体系和铁离子总还原能力(FRAP)体系检测10种ELNs的体外抗氧化能力,MTT法检测各组PC12细胞活力。结果:10种ELNs对DPPH自由基的清除能力从高到低依次为蘑菇、洋葱、生姜、柠檬、葡萄、番茄、青椒、西兰花、山药和大蒜。10种ELNs对ABTS阳离子自由基的清除能力从高到低依次为生姜、蘑菇、洋葱、柠檬、山药、葡萄、青椒、大蒜、番茄和西兰花。10种ELNs对FRAP体系的总抗氧化能力从高到低依次为生姜、青椒、洋葱、蘑菇、柠檬、西兰花、葡萄、山药、番茄和大蒜,其中抗氧化能力相对较强的5种ELNs对DPPH自由基、ABTS阳离子自由基的清除能力以及FRAP随着ELNs浓度升高而增大,半数抑制浓度(IC50)值分别为洋葱73.15、 123.02和83.00 g·L^(-1),生姜124.07、 91.24和91.24g·L^(-1),蘑菇310.44、 518.04和237.10g·L^(-1),青椒969.06、 847.32和237.10 g·L^(-1),柠檬1 718.94、 544.38和962.12 g·L^(-1);与对照组比较,600μmol·L^(-1)过氧化氢组PC12细胞活力下降约30%。与过氧化氢组比较,过氧化氢+ELNs组(青椒、柠檬、山药和西兰花)PC12细胞活力明显提高21.08%、26.2%、11.72%和15.15%。结论:生姜、蘑菇、柠檬和洋葱来源ELNs外泌体在DPPH自由基清除体系、ABTS阳离子自由基体系和FRAP体系中均表现出较强的抗氧化能力。青椒、柠檬、山药和西兰花来源ELNs对过氧化氢诱导的PC12细胞氧化损伤具有保护作用。

黄秋葵提取物体外抗氧化活性的研究

目的:对黄秋葵不同器官水提取物的体外抗氧化作用进行研究,并分别测定其多酚与黄酮含量,为黄秋葵的开发提供一定的理论依据。方法:回流提取获得黄秋葵果、叶、花和种子的水提物,通过FRAP法、自由基的清除(DPPH·)和还原能力的测定对黄秋葵各器官水提物的体外抗氧化活性进行评价,采用NaNO_2-Al(NO_3)_3-NaOH显色体系和Folin-Cioealteau显色法分别测定黄秋葵果、叶、花和种子中的总黄酮含量和总酚含量。结果:黄秋葵不同器官水提物的抗氧化活性有差异,其中黄秋葵嫩果种子水提物的抗氧化活性相对最强,其FRAP值为1.202mmol/g,对DPPH·自由基的EC50值为43.46μg/m L,且种子的总黄酮含量和总多酚含量最高,分别为11.89mg/g和87.78mg/g。结论:黄秋葵果、叶、花和种子均具有良好的抗氧化活性,尤其是种子,具有潜在的开发价值。

奇亚籽提取物体外抗氧化活性研究

奇亚籽是唇形科植物芡欧鼠尾草的种子,已被证实具有多种健康促进作用。文中评价了白奇亚籽和黑奇亚籽的体外抗氧化活性并测定了其总多酚和总黄酮含量。结果表明:2种奇亚籽提取物均能够以浓度依赖的方式清除DPPH·和ABTS^+·,白奇亚籽提取物对DPPH·和ABTS^+·的清除能力显著高于黑奇亚籽提取物;白色和黑色奇亚籽提取物的FeSO_4·7H_2O当量分别为(41.48+2.84)μmol/g和(29.70±2.43)μmol/g;同时,2种奇亚籽提取物均能显著抑制亚油酸自由基引起的β-胡萝卜素漂白。此外,2种奇亚籽提取物均能够有效抑制自由基诱导的亚油酸过氧化和牛血清白蛋白氧化降解。白奇亚籽和黑奇亚籽中总多酚含量分别为(3.40±0.09)mg CAE/g和(2.97±0.07)mg CAE/g,总黄酮含量分别为(1.24±0.06)RE mg/g和(1.07±0.08)RE mg/g。

藜麦提取物体外抗氧化活性研究

以产自山西的藜麦为研究对象,以对DPPH·和ABTS+·的清除能力、铁还原力等为指标,评价了其提取物的体外抗氧化活性。结果表明,藜麦提取物对DPPH·和ABTS+·均有较强的清除能力,其IC_(50)分别为(43.13±2.41)mg/m L和(27.91±1.46)mg/m L;FRAP法测得藜麦抗氧化能力为(1.90±0.10)mg Fe SO_4/g;此外,藜麦提取物能够有效抑制自由基引发的亚油酸过氧化和牛血清白蛋白氧化降解。藜麦提取物具有较强的体外抗氧化活性,为其体内抗氧化活性的研究奠定了基础。

猴头菇提取液抑菌及抗氧化活性研究

应用琼脂扩散法、铁离子还原法(FRAP)和自由基清除实验法(DPPH)分别研究了猴头菇四种提取液的抑菌能力、抗氧化活性和自由基清除能力。发现发酵上清液和菌丝开水提取液的抑菌效果较差(p>0.05),菌丝乙醇提取液的抑菌效果较好(p<0.05),菌丝超声提取液具有较强的抑菌效果(p<0.01);菌丝超声破碎液抗氧化活性最高(p<0.01),其次是乙醇提取液和开水提取液(p<0.05),发酵上清液的抗氧化活性最低(p>0.05);超声破碎提取液远大于其他几种提取液的自由基清除能力。结果表明,利用超声波提取的猴头菇提取液抗氧化和抗菌活性最高。

不同种类绿茶提取物抗氧化活性研究

测定了3种绿茶的总多酚、黄酮和花青素含量,利用亚铁离子螯合能力、DPPH清除能力和铁还原力法对3种绿茶提取物的抗氧化活性进行分析,结果表明,绿茶中以黄山毛峰的总酚含量最高。黄酮含量基没有显著性差异。花青素的含量由大到小依次是信阳毛尖、黄山毛峰和营州芽峰。亚铁离子螯合能力,黄山毛峰>信阳毛尖>营州芽峰。在稀释倍数为2时,黄山毛峰的亚铁离子螯合能力分别是信阳毛尖和营州芽峰的1.32倍和1.38倍。在0.25～1mgDW/mL的浓度下,黄山毛峰的对DPPH的清除能力要显著高于信阳毛尖和营州芽峰,而信阳毛尖和营州芽峰之间无显著性差异。在稀释倍数为2时,黄山毛峰的铁还原力分别是信阳毛尖和营州芽峰的1.35和1.4倍。

两种方法测定香辛料提取物抗氧化活性的比较

本实验分别采用TBARS(硫代巴比妥酸反应物)法和FRAP(还原能力)法研究七种香辛料95%乙醇提取物的抗氧化作用。结果表明,七种香辛料提取物均有较好的抗氧化和还原能力。TBARS法测定抗氧化能力大小依次为:甘草>迷迭香>肉豆蔻>姜黄>丁香>白豆蔻>桂皮;FRAP法测定还原能力大小为:丁香>桂皮>肉豆蔻>迷迭香>姜黄>甘草>白豆蔻。两种方法得到的活性顺序存在很大差异,表明活性大小与其体系密切相关。

不同等级道路的运输振动对哈密瓜贮藏过程中抗氧化系统的影响

不同道路对哈密瓜贮藏过程中抗氧化系统的影响均不同,因此本实验模拟半挂车在高速公路、一级公路、二级公路以及三级公路的运输振动环境,比较经过不同道路振动处理与未经振动处理的哈密瓜在室温(23℃)贮藏期间(28 d)呼吸速率、腐烂指数、总酚含量、VC含量、抗坏血酸过氧化物酶活力、超氧化物歧化酶活力、过氧化氢酶活力、过氧化物酶活力以及Fe^(3+)还原能力、1,1-二苯基-2-三硝基苯肼自由基清除能力的变化情况。结果表明:贮藏28 d时,不同等级道路振动后的哈密瓜7种指标(总酚含量、VC含量、抗坏血酸过氧化物酶活力、超氧化物歧化酶活力、过氧化氢酶活力、过氧化物酶活力以及Fe^(3+)还原能力、1,1-二苯基-2-三硝基苯肼自由基清除能力)均低于对照组,其中二级公路及三级公路相对于高速公路和一级公路对哈密瓜呼吸作用和腐烂率的促进以及抗氧化系统的破坏更为显著(P<0.05);说明振动会促进哈密瓜贮藏期间的呼吸作用,降低抗氧化保护系统中各种酶及抗氧化活性,从而加速细胞膜脂氧化,破坏细胞膜完整性,最终加快哈密瓜的衰老与腐败,其中二级公路和三级公路的运输振动更为显著。

维吾尔药铁力木不同极性部位体外抗氧化作用的研究

目的 研究维吾尔药铁力木不同极性部位的体外抗氧化活性。方法 以Vc为对照,通过测定铁力木乙醇提取物、水提取物及乙醇提取物石油醚（沸程60-90℃）、乙酸乙酯、正丁醇、水各萃取物对Fe^3＋的还原能力、对DPPH自由基（DPPH·）和超氧自由基（O2^-）的清除能力,研究铁力木的体外抗氧化活性。结果 铁力木各部位对Fe^3＋均表现出一定的还原能力,对DPPH·及O2^-均表现出一定的清除作用,但作用均弱于VC。其中水层及正丁醇层对Fe^3＋的还原能力较强,而其石油醚层和乙酸乙酯层还原能力较弱;水层和水提取物对DPPH·具有一定的清除能力;石油醚层及水提取物清除O2^-的作用较强。结论铁力木具有较好的抗氧化能力。

酸浆果实中多酚的提取及其抗氧化能力研究

以酸浆果实为研究对象,对其多酚提取工艺进行优化并分析其(Ferric reducing antioxidant power,FRAP)还原亚铁离子的能力)。采用响应面法对乙醇体积分数、料液比、温度、提取时间进行优化,确定酸浆果实多酚的最佳提取条件,并采用FRAP对多酚提取物的体外抗氧化能力进行分析。结果表明:酸浆果实多酚的最佳提取条件为乙醇体积分数61.5%、料液比1∶15(g/m L)、浸提温度59℃、提取时间102 min,所得多酚得率为0.899%DW,与预测值偏差不大。酸浆多酚10 mg/m L时FRAP值为0.495 mmol/L。研究表明酸浆果实中含有多酚类物质,且具有一定的还原亚铁离子的能力。

大蒜不同极性萃取物的体外抗氧化活性

为了研究大蒜不同极性萃取物的抗氧化活性,确定大蒜的活性部位,促进大蒜资源在天然抗氧化剂和药品等领域的应用,文中采用体积分数80%乙醇回流提取、梯度萃取得到石油醚萃取物、乙酸乙酯萃取物、正丁醇萃取物和水萃取物4个不同极性部位。以清除二苯代苦味酰基(DPPH)自由基、还原力和对肝脂质过氧化抑制力为评价指标研究其体外抗氧化活性。结果表明:大蒜不同极性萃取物均有一定的抗氧化活性,其抗氧化能力与不同极性萃取物的质量浓度呈现出良好的线性依赖关系,抗氧化效果因反应体系不同而有所不同。正丁醇萃取物在3个体外抗氧化活性模型中均表现出较好的抗氧化活性,其清除DPPH自由基和肝脂质过氧化抑制活性的半数抑制浓度分别为0.46 mg/m L和0.36 mg/m L。大蒜正丁醇萃取物得率较高(7.86%),抗氧化活性较好,可以作为新型有效的天然抗氧化物质进行开发利用。

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(P<0.01),与·OH清除能力之间没有显著相关性。