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1.
A study conducted to determine antioxidants ability of garlic applied in beef fat. Garlic's antioxidants determination has the result in water immersion about 53,66%. The study used a completely randomized statistically design with 5x5 factorial. The first factor was the level of crushed garlic (0, 3, 6, 9 and 12% in w/w) then the second factor for storage time (3, 6, 9 and 12 days) at refrigeration temperature (3-5 °C). Thiobarbituric acid value (TBA) and beef fat level percentage were evaluated. The results show that there was an interaction (P<0.05) between the value of TBA and beef fat level percentage. Garlic crushed could reduce the level percentage of beef fat and slowdown the increasing TBA values during storage at refrigerator temperature.  相似文献   

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为评价新品种GC30加工蕉的抗氧化功效,开发其相关产品,拓宽香蕉产业链,本文以GC30加工蕉和4个主栽品种GC02天宝高蕉、GC07鸡蕉、GC09粉蕉、GC25大蕉为对象,研究不同成熟度(1级和7级,1级全果呈暗绿色,7级全果呈黄色)下香蕉皮、肉及果的多酚含量和抗氧化活性,并基于主成分分析法,对不同品种及成熟度香蕉抗氧化活性进行综合评价。结果表明,所有品种的香蕉皮多酚含量均最高(P<0.01),7级香蕉皮、肉的多酚含量与其1级的没有显著性差异(P>0.05),不同品种的香蕉皮多酚含量具有显著性差异(P<0.05),其中7级GC30香蕉皮的多酚含量最高;不同品种的香蕉果、肉、皮的DPPH自由基清除率、超氧阴离子自由基清除能力和抑制羟自由基能力没有显著性差异(P>0.05),所有品种的7级香蕉皮、肉、果的DPPH自由基清除率、超氧阴离子自由基清除能力和抑制羟自由基能力极显著高于其1级香蕉皮、肉、果(P<0.01);所有品种的香蕉皮金属螯合率极显著大于香蕉果、肉(P<0.01),而品种和成熟度对香蕉皮、肉、果的金属螯合率没有显著影响(P>0.05);不同品种熟香蕉果、肉、皮的抗氧化活性优于生香蕉果、肉、皮的抗氧化活性,其中7级GC30香蕉皮抗氧化活性综合评价排名最高。通过对不同品种和成熟度香蕉的功效成分及抗氧化能力的研究,为香蕉品种的选育、分级分类加工与应用提供理论依据,对增加香蕉产业的收益具有重要意义。  相似文献   

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The degradation kinetics of thiosulfinates and the reduction of antioxidant activity of garlic bulbs cut in slices were studied during steam at 100 °C and in water at 80 and 90 °C. Blanching process led to significant reduction of the antioxidant activity and thiosulfinate contents. The reaction rate constants for loss of thiosulfinate species and antioxidant activity increased with blanching temperature, with activation energies of 7.67 and 89.75 kJ/mol, respectively. The antioxidant activity showed a significant correlation with thiosulfinates (R?=?0.7604), and both the antioxidant activity and thiosulfinate contents decreased with increasing blanching time. The antioxidant activity did not show significant differences after 6 min of steam blanching and 8 min of water blanching at 90 and 80 °C. Regarding the thiosulfinate concentration, there was no significant difference after 8 min of blanching for all temperatures.  相似文献   

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大蒜的生物富硒作用及其硒的形态分析   总被引:1,自引:0,他引:1  
通过大蒜叶面喷施硒肥的田间试验,分析大蒜头和大蒜茎叶中硒含量,采用水提、酸提和酶提3种方法提取大蒜中的硒的形态,利用高效液相色谱联用电感耦合等离子体质谱仪(HPLC-ICP/MS)方法测定普通大蒜和富硒大蒜中的硒形态。结果表明:通过叶面喷施硒肥,大蒜蒜头硒含量从0.047μg/g显著提高到0.200~0.834μg/g (P<0.05),大蒜茎叶硒含量从0.043μg/g显著提高到0.291~0.962μg/g(P<0.05)。通过比较的3种硒形态提取方法,证明酶法提取率最高,为较优方法。普通大蒜和富硒大蒜中的主要硒形态为MeSeCys、SeCys2和SeⅣ。与普通大蒜相比,通过叶面喷施硒肥后,大蒜头中主要转化的有机硒形态为MeSeCys,占总提取硒的81.2%,并进一步通过电喷雾质谱(ESI-MS)鉴定MeSeCys的结构,但酸提液中仍存在未知硒峰,需进一步鉴定。  相似文献   

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燕麦发芽过程中多酚含量及其抗氧化活性的变化   总被引:1,自引:0,他引:1  
以山西产裸燕麦为原料,在控制的条件下发芽72h,每间隔12h取样,研究燕麦发芽过程中多酚含量及其抗氧化活性的变化。试验结果表明:发芽时间对燕麦多酚含量及抗氧化活性有很大的影响。与原粮相比,燕麦发芽过程中游离酚、结合酚及总酚含量均有不同程度的增加;燕麦多酚提取物清除ABTS自由基的能力随着发芽的进行而显著增强;发芽过程中燕麦游离酚和结合酚提取物对质粒DNA损伤的保护作用均优于原粮,但清除羟基自由基能力均低于原粮或与原粮相当。  相似文献   

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It has been evidenced that arsenic in garlic is present in the most toxic inorganic species As(III) and As(V). A non-chromatographic speciation method has been developed for the screening of inorganic toxic species of As in garlic samples by hydride generation atomic fluorescence spectrometry. The determination of As(III) and As(V) was based on the different efficiencies of hydride generation with NaBH4 with and without a previous reduction with ascorbic acid and KI using a system of two proportional equations corresponding to these two different measurement conditions. The extraction efficiency of total arsenic and the stability of As(III) and As(V) in different extraction media (sulphuric acid, perchloric acid, and methanol/water) were evaluated. Based on the extraction yield and the stability of extracted species, 1.0 mol L−1 H2SO4 was selected as the best extracting solution for speciation analysis. The methodology developed allows us a limit of detection of 0.8 and 0.6 ng g−1 for As(III) and As(V), respectively. The relative standard deviation values were 4% for As(III) and 7% for As(V). This method was applied to determine As(III), As(V), and total As in different Spanish garlic samples. The arsenic (III) content varied from 17.1 to 22.1 ng g−1 and As(V) from 54.7 to 67.6 ng g−1. The accuracy of the method was confirmed by the analysis of a certified reference material of tomato leaves treated in the same way as the garlic samples.  相似文献   

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Garlic (Alllium sativum L., Fam Liliaceae) is used medicinally mainly for the treatment of hypercholesterolemia and prevention of arteriosclerosis. Clinical trials have consistently shown that "garlic breath" and body odor are the most common (and well-documented) complaints associated to garlic intake. Case reports have highlighted the possibility that garlic use may cause allergic reactions (allergic contact dermatitis, generalized urticaria, angiedema, pemphigus, anaphylaxis and photoallergy), alteration of platelet function and coagulation (with a possible risk of bleeding), and burns (when fresh garlic is applied on the skin, particularly under occlusive dressings). Consumption of garlic by nursing mothers modifies their infant's behavior during breast-feeding. Finally, garlic may enhance the pharmacological effect of anticoagulants (e. g. warfarin, fluindione) and reduce the efficacy of anti-AIDS drugs (i. e. saquinavir).  相似文献   

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Abstract: In the present study the effects of individual and combined essential oils (EOs) extracted from onion (Allium
cepa
L.) bulb and garlic (Allium sativum L.) clove on the growth of Aspergillus versicolor and sterigmatocystin (STC) production were investigated. The EOs obtained by hydrodistillation were analyzed by GC/MS. Twenty one compounds were identified in onion EO. The major components were: dimethyl‐trisulfide (16.64%), methyl‐propyl‐trisulfide (14.21%), dietil‐1,2,4‐tritiolan (3R,5S‐, 3S,5S‐ and 3R,5R‐ isomers) (13.71%), methyl‐(1‐propenyl)‐disulfide (13.14%), and methyl‐(1‐propenyl)‐trisulfide (13.02%). The major components of garlic EO were diallyl‐trisulfide (33.55%), and diallyl‐disulfide (28.05%). The mycelial growth and the STC production were recorded after 7, 14, and 21 d of the A. versicolor growth in Yeast extract sucrose (YES) broth containing different EOs concentrations. Compared to the garlic EO, the onion EO showed a stronger inhibitory effect on the A. versicolor mycelial growth and STC production. After a 21‐d incubation of fungi 0.05 and 0.11 μg/mL of onion EO and 0.11 μg/mL of garlic EO completely inhibited the A. versicolor mycelial growth and mycotoxins biosynthesis. The combination of EOs of onion (75%) and garlic (25%) had a synergistic effect on growth inhibition of A. versicolor and STC production. Practical Application: A substitution of synthetic preservatives with natural antimicrobial compounds in food safety to control fungal contamination and mycotoxin production.  相似文献   

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目的:比较大花罗布麻根、茎、叶、花4 个部位中游离态和结合态酚类物质的含量和抗氧化活性的差异,并分析含量与抗氧化活性之间的相关性。方法:采用Folin-Ciocalteu法、NaNO2-Al(NO3)3法分析罗布麻的根、茎、叶、花4 个部位的游离态和结合态总多酚、总黄酮含量,采用DPPH自由基清除能力、ABTS+·清除能力和铁离子还原能力3 种方法评价其体外抗氧化能力差异。结果:大花罗布麻总酚含量次序为:叶>根>花>茎,各样品间存在显著性差异(P<0.05)。各部位游离酚、结合酚和总多酚含量分别介于3 560.19~6 273.23、13.45~22.01和3 582.2~6 286.68 mg GAE/100 g干质量,其游离态多酚占总酚含量百分比平均为99.60%;游离态黄酮、结合态黄酮和总黄酮含量分别介于1 080.30~2 488.21、9.69~28.59、1 106.81~2 516.80 mg RE/100 g 干质量,其游离态黄酮占总黄酮含量的百分比平均为98.64%。大花罗布麻叶提取物清除DPPH 自由基、ABTS+·能力和总还原力最强,抗氧化活性与总酚含量之间具有良好的线性关系(r>0.950 0)。结论:大花罗布麻各部位中含有较丰富的酚类物质,具有较强的抗氧化活性。  相似文献   

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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.  相似文献   

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草莓、黑莓、蓝莓中多酚类物质及其抗氧化活性研究   总被引:5,自引:0,他引:5  
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。  相似文献   

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Four raisin (Vitis vinifera L.) varieties, Chriha, Razeki, Assli, and Meski, were evaluated for total phenolic content, total o-diphenol content, total flavonoid content, total condensed tannin, total carotenoid content, and total anthocyanin content. Antioxidant potential was assessed by three assays: 2,2-Diphenyl-1-Picrylhydrazyl and 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid radical scavenging capacity and ferric reducing power. Individual phenolic profiles were determined by high-performance liquid chromatography. The results revealed that the four raisin varieties had considerable phenolic content and antioxidant activity. Chriha had the highest total phenolic content (534.2 mg/g dry weight) while Meski had high total condensed tannin (208.6 mg CEQ/g dry weight), TAC (137 mg/100 g dry weight), total o-diphenol content (115.8 mg/g dry weight), total flavonoid content (93 mg CEQ/g dry weight), and total carotenoid content (33 mg/100 g dry weight). There were significant differences in phenolic content among the four varieties (p < 0.05). Meski had the highest 2,2-Diphenyl-1-Picrylhydrazyl scavenging capacity, while Chriha had adequate reducing power and 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid scavenging capacity. The individual phenolic compounds (2.96–6.54 mg/g dry weight) were variety-dependent.  相似文献   

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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。  相似文献   

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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.  相似文献   

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Cooking can change the polyphenol contents of eggplant. This study elucidated the effects of grilling on total polyphenol content (TPC), antioxidant capacity, and the inner structures of eggplant. After identical hollowing, cylindrical eggplant samples were prepared and were then grilled until their center temperatures (CT) respectively reached 50, 65, 75, 85, and 95 °C. Chemical assays and observations of the inner structures clarified that TPC and 1, 1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity decreased as CT increased when CT was below 65 °C. Results also showed that TPC and DPPH radical scavenging activity increased as CT increased when CT was between 65 °C and 95 °C. For CT 65 °C, the samples retained polyphenol oxidase (PPO) activity up to 40% of the raw state activity. The 3 grilled eggplant models, chlorogenic acid, chlorogenic acid—sugar and chlorogenic acid—amino acid model, yielded results showing that phenol functional groups on chlorogenic acid were thermally stable and that phenol functional groups on chlorogenic acid reacted neither with sugar nor with amino acids. Results show that PPO activity is a primary reason for the decrease of the 2 indices. Optical microscopic and scanning electron microscopic observations revealed collapsed cells and inter‐tissue cracks around the surface area for CT 85 and 95 °C. Scanning electron microscopic observations clarified that intercellular bonds for CT 85 and 95 °C became thinner than those for CT 75 °C around the middle area. The phenomena explained above are reasons for the increase of TPC and DPPH radical scavenging activity.  相似文献   

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In this study, total phenolic content, antioxidant activity, mineral content and selected physicochemical properties of three white mulberry phenotypes (Morus alba L.) grown in Turkey were measured. Moisture, total soluble solids, total sugar, sucrose, reducing sugar, protein, ash, pH, titratable acidity, color (L, a, b), vitamin C, total phenolic, antioxidant activity of fruits were determined between 72.85–79.75 g/100 g fresh fruit, 21.25–28.50 g/100 g fresh fruit, 12.18–17.02 g/100 g fresh fruit, 1.57–4.36 g/100 g fresh fruit, 9.42–15.46 g/100 g fresh fruit, 0.82–0.89 g/100 g fresh fruit, 2.20–2.65 g/100 g fresh fruit, 5.70–5.86, 0.25–0.28 g/100 g fresh fruit, 31.24–68.69, ?2.46 to 15.68, 4.58–21.74, 10.15–21.50 mg/100 g fresh fruit, 18.16–19.24 μg gallic acid equivalent/mg of sample, and 33.96–38.96%, of sample respectively. Fruits were generally found high in P and low in Ca.  相似文献   

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