新疆树莓果实营养成分及其提取物抗氧化性研究

目的分析新疆野生树莓果实营养成分,并对其提取物进行抗氧化活性测定。方法进行营养保健成分含量分析,并对果实95%乙醇提取物经石油醚脱脂后,依次用乙酸乙酯、正丁醇萃取,观察不同萃取部位对DPPH·和·OH的清除能力。结果树莓鲜果中必需氨基酸含量高达320mg%,非必需氨基酸中谷氨酸含量较高(180mg%);富含维生素C(28.04mg%)和钾(147.32mg%);有机酸含量高达1.72%,以柠檬酸为主;其它如总酚、总黄酮、鞣化酸、单宁含量分别为498、125、2.2和290mg%,SOD活性高达606.93U/ml。树莓不同提取物均显示了较好的抗氧化活性,以乙酸乙酯部分最高,与清除DPPH自由基相比,清除羟自由基能力强。结论新疆野生红树莓果富含多种营养保健成分和抗氧化活性,有很好的开发价值。     

梨果仙人掌果多酚分布及生物活性

目的 了解梨果仙人掌果多酚分布,并研究其抗氧化和抑制糖消化酶活性。方法 以乙醇为提取溶剂,分离出梨果仙人掌果果皮、果肉和种子中的游离多酚、酯化多酚和不可溶键合多酚,Folin-Ciocalteu法测定多酚含量,通过DPPH自由基、羟自由基、ABTS~+·清除实验测定其抗氧化能力,观察各部位各种类型多酚对α-葡萄糖苷酶和α-淀粉酶活性的体外抑制作用。结果 梨果仙人掌果中果皮多酚含量为(1427.15±34.48)mg GAE/100 g,果肉多酚含量为(525.88±51.66)mg GAE/100 g,种子多酚含量为(256.92±3.81)mg GAE/100 g;梨果仙人掌果不同部位的游离多酚、酯化多酚、不可溶键合多酚对DPPH自由基、羟自由基、ABTS~+·均有一定的清除能力,各部位间以种子的抗氧化能力最强;梨果仙人掌果果皮、果肉和种子的酯化多酚、不可溶键合多酚对α-葡萄糖苷酶和α-淀粉酶活性均有抑制作用,以种子多酚抑制能力最强。结论 梨果仙人掌果果皮多酚含量最高,种子多酚体外抗氧化和抑制糖消化酶作用最强。     

光皮木瓜多酚类的提取和清除DPPH的抗氧化活性

目的:从光皮木瓜中提取多酚类物质,分析其成分含量并测定其多酚的抗氧化活性。方法:将光皮木瓜分为水提物和醇提物两部分,采用纤维素酶解方法处理原料,进行对比实验。在实验中以分光光度法测定其总多酚、单宁和黄酮类含量;薄层色谱定性分析其单体成分;DPPH自由基清除实验测定其抗氧化性能。结果:光皮木瓜提取物中的总多酚为1801mg/100gFW,其中单宁935mg/100gFW,黄酮类294mg/100gFW,酶解有助于多酚含量的提高(P<0.05);薄层色谱的定性分析显示含有儿茶素单体和绿原酸;DPPH自由基清除效应实验结果指出水提物清除自由基的活性较醇提物强,而且酶解后各部分的活性均增强。结论:光皮木瓜提取物中的多酚类物质含量较高并有较强的抗氧化活性。     

地参游离酚对α-葡萄糖苷酶和胰脂肪酶的抑制作用研究

目的探讨地参游离酚对α-葡萄糖苷酶和胰脂肪酶活性的抑制作用。方法采用福林-酚法测定地参游离酚的酚含量,并采用HPLC对其酚类化合物进行分析。通过体外实验,以抑制率为指标,测定地参游离酚对α-葡萄糖苷酶和胰脂肪酶活性的抑制作用。结果地参游离酚的酚含量为502.33~586.53μg GAE/mg EDW,主要酚类化合物是迷迭香酸,含量为319.70~400.46μg/mg EDW;地参游离酚对α-葡萄糖苷酶及胰脂肪酶均有抑制作用,且呈现剂量-效应关系。地参游离酚抑制α-葡萄糖苷酶的IC50值范围为0.238 4~1.281 8g/L,抑制胰脂肪酶的IC50值范围为2.030 5~3.042 7g/L。结论地参游离酚对α-葡萄糖苷酶和胰脂肪酶活性有抑制作用,可作为α-葡萄糖苷酶和胰脂肪酶抑制剂。     

七个不同产地山楂的营养成分分析和抗氧化能力评价

目的对7个不同产地的山楂果实进行营养成分含量研究,同时对其总抗氧化能力进行评价。方法主要对山楂果实的宏量营养素、水分、维生素、矿物质等几项营养成分进行测定,同时选择高效液相色谱法测定了山楂果实的酚酸及多酚类功效成分及总有机酸含量。采用氧自由基吸收能力(oxygen radical absorbance capacity,ORAC)法,以维生素C为质控样品,对不同品种山楂果的总抗氧化能力进行评价。结果研究结果表明,山楂鲜果中碳水化合物主要有果糖和葡萄糖组成,其含量在1.57%～4.28%范围内;山楂果实含水量均值为75.5%,含有少量的膳食纤维,在5.79～8.07g/100g范围内;富含维生素C,5#样品含量最低,为72.3 mg/100g,6#样品含量最高,为97.7 mg/100g,β-胡萝卜素含量范围为100～208μg/100g;山楂鲜果含有多种矿物质,其中钾含量最高,在232.25～311.30 mg/100g范围内,其次是钙和磷,含量分别为20.29～37.45 mg/100g、11～25 mg/100g;铁和锌的含量均低于1.50 mg/100g。山楂果实中富含多种酚酸及多酚类功效成分,总有机酸检测结果表明山楂果实中柠檬酸>苹果酸>酒石酸。ORAC值在170.3～304.2μmol Trolox当量/g范围内。结论山楂鲜果富含多种营养成分及多酚类功效成分,具有较强的抗氧化能力,相关分析结果表明,山楂鲜果总黄酮与ORAC值存在正相关,相关系数r=0.981(P<0.01);山楂鲜果总多酚与ORAC值存在正相关,相关系数r=0.886(P<0.01)。     

中国石蒜总生物碱提取工艺优化及其含量动态变化

目的:探讨超声提取中国石蒜(Lycoris chinensis)总生物碱的最佳工艺条件,以及不同产地、不同部位和不同时期总生物碱含量的动态变化。方法:在单因素实验的基础上,采用正交实验优化中国石蒜总生物碱超声提取工艺,以石蒜碱为标准品,用比色法测定中国石蒜总生物碱含量。结果:料液比和乙醇浓度是影响中国石蒜总生物碱超声提取效果的主要因素;中国石蒜鳞茎总生物碱含量在开花期最高,盛叶期含量最低,但各个时期总碱含量没有显著性差异(P0.05),其范围在5.2~5.6 mg/g之间;不同产地中国石蒜鳞茎总生物碱含量差异明显(P0.05),琅琊山居群最高,黄山居群最低;中国石蒜果实的总生物碱含量最高,达9.19 mg/g,其次是花序,叶片中含量最低。结论:在超声工作频率为40 KHz时,中国石蒜总生物碱最佳超声提取工艺为:提取温度60℃,乙醇浓度65%,料液比为1:20,提取时间为2 h。     

红花籽粕不同极性部位体外抗氧化活性研究

目的测定红花籽粕不同极性提取物的抗氧化活性。方法利用不同极性的溶剂提取并萃取出红花籽粕的24个萃取物,并采用1,1-二苯基-2-三硝基苯肼(DPPH)法、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)法和对硝基酚邻酸盐(PNPP)法对抗氧化能力进行测定。结果 95%乙醇提取物氯仿萃取物提取率最高。不同极性提取物对DPPH和ABTS自由基均有一定的清除作用,对蛋白酪氨酸磷酸1B酶(PTP1B)活性有抑制作用。结论红花籽粕具有较好的抗氧化能力,具有开发利用的价值。     

新疆不同产地药桑葚总黄酮含量及其抗氧化活性

目的 基于响应面设计优化药桑葚总黄酮的提取工艺,比较新疆不同产地药桑葚总黄酮含量的差异及其与抗氧化活性间的关系。方法 通过单因素实验考察乙醇体积分数、料液比、超声功率和超声时间对药桑葚总黄酮含量测定的影响,采用Box-Behnken响应面设计优化得出最优提取工艺参数。同时以羟自由基清除能力、铁离子还原能力等抗氧化活性指标评价药桑葚的体外抗氧化活性。结果 最佳提取工艺为乙醇体积分数45%、料液比1∶20 g/mL、超声功率300 W、超声时间60 min,该条件下,6个产地药桑葚的总黄酮含量库车市>喀什市>库车乌恰镇>和田市>英吉沙县>于田县,其中库车市的药桑葚总黄酮含量为(27.159±0.091)mg/g,不同产地药桑葚总黄酮含量差异具有统计学意义(P<0.05)。体外抗氧化活性分析显示,库车市与和田市的药桑葚抗氧化活性较强,各产地药桑葚的羟自由基清除能力、铁离子还原能力和总抗氧化能力差异具有统计学意义(P<0.05)。相关性分析发现,药桑葚的总黄酮含量与抗氧化能力具有相关性,可加强羟自由基清除作用。结论 超声波辅助法提取药桑葚总黄酮简便,所...     

不同干燥方法红枣中维生素C含量测定分析

[目的]测定不同干燥方法红枣中维生素C含量,为食品营养成分分析提供参考数据。[方法]分别采用自然晒干、微波干燥、电热恒温干燥的方法处理样品,用草酸提取各样品中维生素C,37℃时与2,4-二硝基苯肼反应,用分光光度法于波长490nm处测定吸光度。[结果]鲜枣中含维生素C324.38mg/100g,随着自然日晒天数的增多维生素C含量迅速减少;电热恒温干燥的样品维生素C含量21.16mg/100g;微波干燥样品维生素C含量94.04mg/100g。[结论]微波干燥处理的红枣维生素C含量最高,显著高于自然晒制20d和电热恒温干燥的样品。自然干燥过程中前7d果实维生素C含量下降幅度较小,8d后果实维生素C含量显著下降,约2周后果实维生素C的含量变化不大。     

两种不同产地龟板抗氧化活性研究

[目的]研究两种不同产地龟科动物乌龟Chinemys reeresii(Gray)腹甲提取物的抗氧化活性。[方法]采用DPPH法分别测定两种不同产地龟板的石油醚、乙酸乙酯、95%乙醇等不同极性溶剂提取物的抗氧化活性。[结果]不同产地龟板95%乙醇提取物抗氧化活性均最强;海南产龟板抗氧化活性比湖北汉阳产龟板强,差异有统计学意义(P﹤0.01)。[结论]不同产地的龟板所含抗氧化成分存在一定的差异。     

Assessment of phenolic acid content and in vitro antiradical characteristics of hawthorn

The infusions and extracts obtained from leaves with flowers, fruit peel, and seed from hawthorn (Crataegus monogyna Jacq., Family Rosaceae) were subjected to evaluation as potential sources of antioxidant phytochemicals on the basis of their total content of phenolics, levels of phenolic acids, and in vitro antiradical activity. Total phenolic content of extracts was determined using the modified Folin-Ciocalteau method. Antioxidant activity was determined for phenolic extracts by a method involving the use of the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). Phenolic acids containing extracts and infusions from hawthorn leaves, fruit peel, and seeds were obtained using different polarity solvents and separated by reverse-phase high-performance liquid chromatography, which enabled improved separation by the use of a C(18) column, an acidic mobile phase, and gradient elusion. The highest total phenolic content (343.54?mg of gallic acid equivalents/g) and the highest DPPH radical scavenging activity as the inhibition percentage (60.36%) were obtained in ethyl acetate extract from hawthorn leaves with flower. Also, the highest phenolic acid content was measured in the extracts of hawthorn leaves with flowers: protocathechuic (108-128?mg/100?g), p-hydroxy benzoic (141-468?mg/100?g), caffeic (137-3,580?mg/100?g), chlorogenic (925-4,637?mg/100?g), ferulic (3,363-3,462?mg/100?g), vanillic (214?mg/100?g), and syringic (126?mg/100?g) acids. The results indicate that hawthorn is a promising plant because of its high antioxidant activity.     

Radical scavenging, antibacterial, and antiproliferative activities of Melissa officinalis L. extracts

The aromatic herb Melissa officinalis L. can be used as an easily accessible source of natural antioxidants and as a possible food supplement and as a phytochemical. Radical scavenging, antibacterial, and antiproliferative activities of petroleum ether, chloroform, ethyl acetate, n-butanol, and water extracts of M. officinalis L. extracts were investigated. The results of antioxidative activity, obtained by electron spin resonance spectroscopy, confirmed that investigated extracts suppressed the formation of 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, and lipid peroxyl radicals in all investigated systems in a dose-dependent manner. The maximum DPPH and hydroxyl radical scavenging activities (SA(DPPH) = SA(OH) = 100%) were achieved in the presence of n-butanol extract at concentrations of 0.4 mg/mL and 0.5 mg/mL, respectively. The highest lipid peroxyl scavenging activity (93.20%) was observed at a higher concentration (5 mg/mL) of n-butanol extract in the lipid peroxidation system. The most effective antibacterial activities were expressed by petroleum ether and ethyl acetate extracts on Sarcina lutea. Chloroform extract showed the strongest antiproliferative effect with 50% inhibitory concentration values of 0.09 mg/mL and 0.10 mg/mL for HeLa and MCF-7 cell lines, respectively. The present study demonstrated the high phenolic content and radical scavenging, antibacterial, and antiproliferative activities of extracts of M. officinalis L. originating from Serbia.     

牛角瓜花的抑菌活性研究

目的以牛角瓜花为实验材料,对其抑菌活性进行研究。方法以索氏提取法得到牛角瓜花的石油醚、氯仿、乙酸乙酯和甲醇的粗提物,并选择白色念珠菌等6种真菌和金黄色葡萄球菌等7种细菌,采用纸片琼脂扩散法对不同溶剂粗提物进行抑菌活性测定。结果牛角瓜花的石油醚粗提物对黄曲霉、枯草芽孢杆菌和尖孢镰刀菌表现出优秀的抑菌效果,抑菌圈直径分别为13.37、12.81、12.25 mm,均优于阳性对照氟康唑和两性霉素B的抑菌活性;氯仿粗提物对枯草芽孢杆菌、大肠埃希菌和白色念珠菌表现出良好的抑菌活性,抑菌圈直径分别为11.73、11.10、10.84 mm;乙酸乙酯和甲醇粗提物的抑菌效果较弱,乙酸乙酯粗提物对黄曲霉的抑菌圈直径为12.81 mm,甲醇粗提物对黑曲霉的抑菌圈直径为9.90 mm,且两种粗提物对其他供试菌有较弱或无抑菌效果。结论牛角瓜花中的化学成分在不同溶剂中的溶解性不同,使得4种溶剂粗提物的抑菌能力存在差异。     

Determination of total phenolic content of raspberry and blackberry cultivars by immobilized horseradish peroxidase bioreactor

Raspberry and blackberry cultivars were assayed for total phenol content by enzymatic method using immobilized horseradish peroxidase (HRP). The HRP was immobilized on the styrene–divinylbenzene–polygluteraldehyde (STY–DVB–PGA) beads. Total phenol content determined by immobilized and free enzymatic methods was compared with those obtained by applying the Folin–Ciocalteu method. The total phenol content by immobilized HRP method ranged from 254 to 973 mg gallic acid equivalent (GAE) per 100 g fw as well as 105 to 435 mg ellagic acid equivalent (EAE) per 100 g fw in raspberry and blackberry cultivars. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical values were correlated with total phenol content in raspberry using immobilized enzymatic method as GAE (R² = 0.7450, P = 0.05) and EAE (R² = 0.7449, P = 0.05). All antioxidant activity values were highly correlated with total phenol content in blackberry using free and immobilized enzymatic methods as GAE (R² = 0.9777 and 0.9223, P = 0.05 respectively) and EAE (R² = 0.9979 and 0.9223, P = 0.05 respectively). A significant additivity was observed using individual phenolic compounds by immobilized enzymatic method as 95% (GAE) and 90% (EAE). These results show that the immobilized enzymatic assay can be applied to determine the total phenol content of berry fruits, which is more specific and not affected by interfering compounds.     

Antioxidant properties of palm fruit extracts

Phenolic compounds have been shown to exhibit bioactive properties, and in particular antioxidant effects. A phenolic-rich fraction has been isolated from the aqueous by-product obtained during the milling of oil palm fruits. The objectives of the study were to determine the phenolic content of the crude and ethanolic extracts of oil palm fruits and to evaluate the antioxidant properties of these extracts. The total phenolics content of the crude and ethanol extracts as determined by the Folin-Ciocalteu method were found to be 40.3 +/- 0.5 and 49.6 +/- 0.6 mg GAE/g extract (dry basis), respectively. The radical scavenging activity of the extracts determined using 2,2 diphenyl-1-picrylhydrazyl radical (DPPH.) indicated that both crude and ethanol extracts exhibit hydrogen-donating capacity, and have antiradical power (ARP) comparable to ascorbic acid. The DPPH radical scavenging activity of the extracts were less than that of gallic acid, but the time-course variations of the scavenging curves suggest that the extracts acted by a mechanism similar to that of gallic acid. The electron-donating potentials of the extracts were inferred from the hydrogen peroxide scavenging and reducing power assays. The reducing power of crude and ethanol extracts at 1 mM GAE were found to be comparable to that of 0.3 mM gallic acid. The extracts indicated complete scavenging of hydrogen peroxide at concentrations above 0.4 mM GAE. These findings suggest that the crude and ethanol extracts are able to scavenge free radicals, by either hydrogen or electron donating mechanisms, and can therefore act as primary antioxidants.     

Antioxidant activity of methanolic extract of emblica fruit (Phyllanthus emblica L.) from six regions in China

The phenolic contents of methanolic extracts of emblica (Phyllanthus emblica L.) fruit from six regions in China were measured in this work. The antioxidant activities of these extracts were also evaluated. Total phenolic content was ranged from 81.5 to 120.9 mg gallic acid equivalents (GAE)/g and the flavonoid content was varied from 20.3 to 38.7 mg quecetin equivalents (QE)/g, while proanthocyanidin content was ranged from 3.7 to 18.7 mg catechin equivalents (CE)/g. Among all the methanolic extracts analyzed, the Huizhou sample exhibited a significantly higher phenolic content than other samples (P<0.05). The antioxidant activities were evaluated by in vitro experiments using scavenging assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, hydroxyl radicals, and superoxide anion radicals, chelating ability of ferrous ion, reducing power, and inhibition capability of Fe (II)-induced lipid peroxidation, respectively. The Huizhou sample was found to have the strongest antioxidant activities in scavenging DPPH radicals, superoxide anion radicals, and had the highest reducing power, while the Chuxiong sample showed the best performance in chelating iron and inhibiting lipid peroxidation. Furthermore, the Chuxiong sample exhibited a stronger inhibition activity of the hydroxyl radicals compared with other samples. The high correlation coefficient was existed between the phenolic content and superoxide anion radical scavenging activity, but no significant correlation was found between the former and hydroxyl radical scavenging activity. Methanolic extracts of emblica fruit from some selected regions exhibited stronger antioxidant activities compared to those of the commercial compounds (quercetin and BHA). It might be considered as a potential plant source of antioxidants.     

Antimicrobial activities of various fractions of longan (Dimocarpus longan Lour. Fen Ke) seed extract

The antimicrobial activities of longan (Dimocarpus longan Lour. Fen ke) seed extracts were investigated using a disc diffusion method and also determining the minimal inhibitory concentration. The DL-P01-SI01 fraction showed that the strongest activity against Staphylococcus aureus and methicillin-resistant S. aureus at MIC 64?μg/mL, which was found to be due to the phenolic compounds. The HPLC analysis showed that the major phenolic compounds are gallic acid, corilagin, ethyl gallate and ellagic acid.     

The antioxidant and radical scavenging activities of black pepper (Piper nigrum) seeds

Water and ethanol crude extracts from black pepper (Piper nigrum) were investigated for their antioxidant and radical scavenging activities in six different assay, namely, total antioxidant activity, reducing power, 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. Both water extract (WEBP) and ethanol extract (EEBP) of black pepper exhibited strong total antioxidant activity. The 75?µg/ml concentration of WEBP and EEBP showed 95.5% and 93.3% inhibition on peroxidation of linoleic acid emulsion, respectively. On the other hand, at the same concentration, standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and α-tocopherol exhibited 92.1%, 95.0%, and 70.4% inhibition on peroxidation of linoleic acid emulsion, respectively. Also, total phenolic content in both WEBP and EEBP were determined as gallic acid equivalents. The total phenolics content of water and ethanol extracts were determined by the Folin-Ciocalteu procedure and 54.3 and 42.8?µg gallic acid equivalent of phenols was detected in 1?mg WEBP and EEBP.     

短果茴芹抗氧化活性成分的提取及筛选

目的对短果茴芹抗氧化活性成分进行提取,并了解其提取物的抗氧化效果。方法采用邻苯三酚自氧化体系、Fenton反应体系和H2O2诱导的氧化损伤模型,了解短果茴芹4种提取物的抗氧化作用。结果所获得的4种提取物均具有抗氧化作用,其中乙酸乙酯层提取物作用最强,这与乙酸乙酯层提取物具有较强的清除O.-2和.OH能力有关;石油醚层提取物虽然也具有较强的清除O.-2和.OH能力,但对人肝癌细胞BEL-7404的氧化损伤无保护作用,反而有抑制肿瘤的效果。结论短果茴芹富含抗氧化活性成分,值得深入研发。