千层金叶片醇提物抗氧化活性的研究

为了探究千层金叶片醇提物的抗氧化活性,本文研究了千层金叶片醇提物及其不同极性部位的抗氧化活性和总多酚含量。研究结果表明：千层金叶片醇提物正丁醇相的总多酚含量最高,为(453.75±0.75) mg/g;75%甲醇粗提物及其正丁醇相对ABTS ⁺自由基的清除能力较抗坏血酸（VC）强;各组分还原力强弱顺序为VC>正丁醇相>75%甲醇粗提物>水相>乙酸乙酯相>BHT>石油醚相;正丁醇相和乙酸乙酯相对DPPH自由基的清除能力较醇提物和水相强,石油醚相最弱;千层金叶片醇提物及其不同极性部位清除ABTS ⁺自由基清除能力、DPPH自由基清除能力及还原力均与其总多酚含量呈正相关。除石油醚相外,千层金叶片醇提物及其不同极性部位均有较强的抗氧化活性,可作为一种良好天然抗氧化剂的物质来源。     

玫瑰茄总黄酮超声波-微波协同提取及抗氧化活性

采用Box-Behnken响应面试验设计法对玫瑰茄总黄酮超声波-微波协同提取工艺进行优化,研究了乙醇浓度、液固比、提取时间、微波功率、提取次数5个单因素对总黄酮提取量的影响,建立了乙醇浓度、液固比和微波功率的三因素回归模型,并研究其抗氧化活性。结果表明,提取的最佳工艺参数为乙醇浓度40%、液固比50∶1（mL/g）、微波功率250 W、提取时间20 min、超声波功率50 W,在此条件下提取2次,总黄酮提取量为40.2 mg/g。同时以维生素C作对照,研究了玫瑰茄总黄酮粗提物和纯化物的体外抗氧化活性。结果表明,玫瑰茄总黄酮粗提物和纯化物都具有较强的抗氧化活性,能够有效清除O₂^-?自由基和DPPH自由基,清除能力与浓度呈较明显的量效关系,但抗氧化能力较维生素C弱。     

Antioxidant and Immunity Activity of Water Extract and Crude Polysaccharide from <Emphasis Type="Italic">Ficus carica</Emphasis> L. Fruit

The antioxidative activities of water extract (WE) and crude hot-water soluble polysaccharide (PS) from Ficus carica L. fruit were investigated using various assays in vitro, including scavenging abilities on DPPH, superoxide and hydroxyl radicals and reducing power. The immunity activities of PS were evaluated using the carbon clearance test and serum hemolysin analysis in mice. In addition, total phenolics and flavonoids contents were also determined. Both WE and PS have notable scavenging activities on DPPH with the EC₅₀ values of 0.72 and 0.61 mg/ml, respectively. The PS showed higher scavenging activity than WE on superoxide radical (EC₅₀, 0.95 mg/ml) and hydroxyl anion radical (scavenging rate 43.4% at concentration of 4 mg/ml). The PS (500 mg/kg) also has a significant increase in the clearance rate of carbon particles and serum hemolysin level of normal mice. The results indicate that both WE and PS might be applicable in healthy medicine and food industry.     

Antioxidant and Antiproliferative Activity of <Emphasis Type="Italic">Diospyros lotus</Emphasis> L. Extract and Isolated Compounds

The object of the study was to determine the chemical composition of Diospyros lotus L. extract and their antioxidant and antiproliferative properties. Eight compounds were isolated from D. lotus and identified as gallic acid, methylgallate, ellagic acid, kaempferol, quercetin, myricetin, myricetin 3-O-β-glucuronide, and myricetin-3-O-α-rhamnoside. D. lotus extract tested in different in vitro systems (DPPH, ABTS, FRAP, and Fe²⁺ chelating activity assay) showed significant antioxidant activity. The potential antiproliferative properties of D. lotus extract and isolated compounds against nine human cancer cell lines such as COR-L23, CaCo-2, C32, ACHN, A375, A549, Huh-7D12, MCF-7, and LNCaP were investigated in vitro by SRB assay. D. lotus extract demonstrated the highest inhibitory activity against COR-L23 with an IC₅₀ value of 12.2 μg/ml. Among identified hydrolysable tannins, ellagic acid evidenced strong antiproliferative activity against both C32 and A375 cells with IC₅₀ values of 0.8 and 4.1 μg/ml, respectively. Interesting results were observed, also, with gallic acid that showed the highest cytotoxic activity against CaCo-2 (IC₅₀ 2.6 μg/ml). Overall, the results of this study suggest that D. lotus displays a good antioxidant activity and has antiproliferative effects. Both activities are related to identified phenolic compounds.     

Antioxidant Activity and Phenylpropanoids of Phlomis lychnitis L.: A Traditional Herbal Tea

Phlomis lychnitis L. (Lamiaceae) is consumed as a traditional herbal tea in Spain. The antioxidant-protective effects as well as its phytoconstituents have never been established. The ability of the methanolic extract to protect cells from oxidative stress was evaluated in rat pheochromocytoma cells (PC12) using hydrogen peroxide as toxic agent. The viability of PC12 cells pre-treated with the methanolic extract of Phlomis lychnitis, determined by the MTT and LDH assays, was significantly improved at the highest dose (p?<?0.01). The antioxidant activity was confirmed evaluating the capacity of the plant to scavenge ABTS, DPPH, O₂ · ^? radicals and to inhibit XO. Bioassay guided fractionation led to antioxidant compounds. Qualitative HPLC/DAD/ESI/MS analysis reported phenylpropanoids, verbascoside being the major antioxidant constituent.     

红厚壳种仁油脂体外抗氧化能力研究

采用4个抗氧化体系对红厚壳种仁油脂的体外抗氧化能力进行研究。结果表明,红厚壳种仁油脂总酚酸含量为(0.26±0.045)mg/mL。0.10%的红厚壳种仁油脂对ABTS+自由基清除能力的TEAC值为123.39μmol/L;5%的红厚壳种仁油脂清除DPPH自由基的能力显著高于100μg/mL的BHT;7.5%的清除羟自由基的能力显著高于100μg/mL的BHT和Trolox;1.6%的对脂质过氧化的抑制能力均不及100μg/mL的BHT和Trolox。说明红厚壳种仁油脂具有显著的抗氧化活性。     

Morus alba L. and Morus nigra L. Leaves as a Promising Food Source of Phenolic Compounds with Antioxidant Activity

Plant Foods for Human Nutrition - Bioactivity of mulberry has been widely described, but mostly related to its fruits, while studies with leaves are scarce. Herein, in this study leaves of two...     

Relationship Among Antimutagenic, Antioxidant and Enzymatic Activities of Methanolic Extract from Common Beans (Phaseolus vulgaris L)

Common beans are rich in phenolic compounds, which can provide health benefits to the consumer. The objective of this work was to study the relationship among antimutagenicity, antioxidant and enzymatic activities of methanolic extract and trolox by principal components multivariate analysis. Antimutagenicity of phenolic compounds present in methanolic extract from the seed coat of common beans (P. vulgaris, Flor de Mayo Bajío cultivar) and trolox against AFB₁ mutagenicity were evaluated in the Salmonella typhimurium microsuspension assay. Antioxidant capacity of methanolic extract and trolox were evaluated using β-carotene and 1,1-diphenyl-2-picryhydrazyl (DPPH) in vitro model assays. Cythrome P450 activity was measured by fluorometric assay. For phenolic extract, trolox and phenolic extract + trolox, the inhibition on AFB₁ mutagenicity in tester strain TA100 was 47, 59 and 69%, respectively. While in TA98 was 39, 48 and 68%. The inhibition of phenolic compounds, trolox and phenolic compounds + trolox on cytochrome P450 (CYP450) activity was 48, 59 and 88%, respectively. Correlation analysis showed that phenolic extract and trolox have high antimutagenic and antioxidant activity and also inhibited enzymatic activity. The results suggest that the primary mechanism of action of phenolic compounds in beans against AFB₁ mutagenicity may be extra-cellular in the microsuspension assay.     

不同茶类特征成分抗氧化特性研究进展

简述近年关于绿茶、红茶、乌龙茶、普洱茶主要茶类特征成分抗氧化特性的研究进展,比较分析其异同点,讨论了有待进一步研究的内容,为开发茶类天然抗氧化剂的研究提供一定的参考。     

大豆荚壳异黄酮制备与体外抗氧化性研究

研究大豆荚壳异黄酮(Isoflavones from soybean hull,ISH)制备与体外抗氧化性作用.通过超声回流法提取和大孔吸附树脂纯化,得到纯化的ISH.以VC、BHT、芦丁和槲皮素为阳性对照,测定了 ISH的还原力;对羟基自由基、超氧阴离子自由基、烷基自由基的清除率以及抑制油脂过氧化的能力.结果表明:ISH的还原力高于BHT和VC,ISH对这几种自由基均有一定的清除作用,ISH的添加量在试验范围内与其抗氧化活性呈正相关.当试验量大于5μg·mL-1时,ISH的抗氧化性能均优于VC、BHT、芦丁和槲皮素.     

A Search for Hepatoprotective Activity of Fruit Extract of Mangifera indica L. Against Oxidative Stress Cytotoxicity

Mango (Mangifera indica L.) and their components are commonly used in folk medicine for many curative effects. The protective effects of different concentrations of aqueous extract of Mangifera indica L. fruit (Mango Extract) (20, 50 and 100 μg/ml) and also gallic acid (100 μM) as a pure compound in the extract were examined against oxidative stress toxicity induced by cumene hydroperoxide (CHP) in isolated rat hepatocytes. The extracts and gallic acid (100 μM) protected the hepatocyte against all oxidative stress markers including cell lysis, ROS generation, lipid peroxidation, glutathione depletion, mitochondrial membrane potential decrease, lysosomal membrane oxidative damage and cellular proteolysis. Mango Extracts (20, 50 and 100 μg/ml) were more effective than gallic acid (100 μM) in protecting hepatocytes against CHP induced lipid peroxidation. On the other hand gallic acid (100 μM) acted more effective than Mango Extracts (20, 50 and 100 μg/ml) at preventing lysosomal membrane damage. In addition H₂O₂ scavenging effect of all extracts were determined in hepatocytes and compared with gallic acid (100 μM). There were no significance differences (P<0.05) between all plant extracts and gallic acid (100 μM) in H₂O₂ scavenging activity. These results suggest a hepatoprotective role for Mango Extract against liver injury associated with oxidative stress.     

紫薯花色苷的提取及抗氧化活性研究

以紫薯‘济黑’为原料,酸化乙醇为溶剂提取其中的花色苷成分,单因素实验探讨不同因素对提取效果的影响,并通过响应面法建立二次多项数学模型,确定紫薯花色苷最佳浸提条件为:乙醇浓度60%、浸提时间127 min、液料比18∶1,该条件下紫薯花色苷实际浸提值为2.680 mg/g。以VC作为对照,从DPPH自由基、超氧阴离子自由基(O2·-)、羟自由基(·OH)清除率及总抗氧化活性4个方面考察了紫薯花色苷的体外抗氧化能力,结果表明,紫薯花色苷粗提物对DPPH、O_2~-·和·OH均有较好的清除活性,其IC50值分别为1.245、332.291和70.830 mg/L,均小于VC的IC50值,紫薯花色苷粗提物的总抗氧化能力为101.38 U/mg,具有较强的抗氧化活性。     

白背天葵多酚的提取及其抗氧化活性

本文研究了白背天葵多酚的超临界CO₂提取工艺及其体内外抗氧化活性,为白背天葵的开发利用提供依据。以萃取压力、萃取时间、萃取温度、CO₂流量和夹带剂浓度为单因素,以多酚提取得率为指标,采用响应面法对提取工艺条件进行优化。采用体外抗氧化活性试验分析提取物对DPPH及ABTS自由基的清除能力。体内抗氧化活性试验以D-半乳糖致衰小鼠为模型,白背天葵多酚提取物150、300、600 mg/kg连续灌胃30 d,测定其血清及肝组织中超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）、过氧化氢酶（CAT）活性和丙二醛（MDA）含量。结果表明,白背天葵多酚的超临界CO₂最优提取工艺为萃取压力35 MPa、萃取时间2 h、萃取温度40 ℃、CO₂流量20 L/h,多酚提取得率为5.32%。体外抗氧化试验表明,多酚对DPPH及ABTS自由基的清除率随其浓度的提高而提高。与空白组比较,衰老模型组血清及肝组织中的SOD、GSH-Px、CAT活性显著性降低,MDA含量显著性升高,白背天葵多酚提取物能显著提高衰老模型组血清及肝组织中的SOD、GSH-Px、CAT活性,并降低MDA含量。     

糖胶树花次生代谢产物及其抗细菌活性

采用水蒸气蒸馏法提取糖胶树花挥发油,通过气相色谱-质谱联用技术(GC-MS)对挥发油进行成分分析,采用薄层层析——生物自显影法测定糖胶树花乙酸乙酯层提取物对供试细菌的抑制活性。结果表明,糖胶树花挥发油得率为0.018%,通过GC-MS分析,从中鉴定出20个成分,占挥发油总量的97.53%,其主要成分为2-莰烯(23.30%),芳樟醇(23.09%),(-)-4-萜品醇(10.54%)。糖胶树花乙酸乙酯层提取物对大肠杆菌表现出较强的抑制活性,其次为黄瓜角斑病菌,对其他供试细菌未表现出抑制活性。     

四川老鹰茶醇提物的抑菌及抗氧化活性研究

以四川3个不同地区的老鹰茶及老鹰茶植物的鲜叶为原料,采用超声波辅助提取技术提取醇提物,测定多酚和黄酮含量以及抑菌和抗氧化性活性.结果表明:6种样品醇提物的提取率最高的为石棉老鹰茶鲜叶,为(26.73±0.68)％;总多酚和总黄酮含量最高的是石棉老鹰茶鲜叶,分别为(22.10±0.11)％和(16.77±0.14)％.6种样品醇提物对4种细菌均有抑制作用,且提取物浓度越高抑菌效果越强;其中石棉老鹰茶鲜叶对痢疾志贺氏菌(Shigella dysenteriae)抑制效果最好,抑菌圈直径达到(2.56±0.09)cm.6种样品醇提物的DPPH(1,1-二苯基-2-三硝基苯肼)自由基清除能力和总还原能力均高于对照品BHT(2,6-二叔丁基对甲酚).6种样品抑菌和抗氧化能力结果由强到弱为石棉老鹰茶鲜叶>叙州老鹰茶鲜叶>青川老鹰茶鲜叶>石棉老鹰茶>叙州老鹰茶>青川老鹰茶.试验表明四川3个不同地区的老鹰茶及老鹰茶植物的鲜叶均具有较强的抑菌和抗氧化活性,其中石棉老鹰茶植物的鲜叶相对更好,可优先开发利用.     

竹荪提取物体内抗氧化活性

利用D-半乳糖制造衰老模型小鼠,研究竹荪提取物在衰老模型小鼠体内的抗氧化作用。结果表明:在低剂量,中剂量和高剂量(50、100、200mg/kg.d)3个剂量条件下,小鼠的体重增量与空白组相比不显著,说明竹荪提取物在实验剂量下没有明显的毒、副作用;中剂量和高剂量下,小鼠肝重、脾重与空白组差异均不显著,与模型组差异分别为显著和极显著,说明竹荪提取物可以有效保护受损内脏,防止氧化损伤;竹荪提取物可明显提高衰老模型小鼠血清中SOD酶活力,降低衰老模型小鼠血清中MDA含量,并且竹荪提取物与小鼠血清中SOD酶活力和MDA含量呈明显的剂量效应关系,说明竹荪提取物具有较强的体内抗氧化活性。     

木麻黄小枝提取物的抗蚁及抑菌生物活性

采用滤纸药膜法测定木麻黄（Casuarina equistiolia Forst小枝提取液对黑翅土白蚁的毒杀和驱避活性,并测定了木麻黄小枝提取液对大肠杆菌、金黄色葡萄球菌、清酒假丝酵母、黑曲霉的抑菌活性。结果表明∶木麻黄小枝水提取液对黑翅土白蚁有显著的触杀毒性,处理浓度为5mg血L条件下,校正死亡率达82%。木麻黄小枝水提取液对黑翅土白蚁无显著的忌避活性,对金黄色葡萄球菌表现出显著的抑制活性。化学成分预试验表明,木麻黄小枝水提取液中含有黄酮类、酚类和糖类等代谢产物。     

Polyphenolics Profile, Antioxidant and Radical Scavenging Activity of Leaves and Stem of Raphanus sativus L.

Aerial parts (leaves and stem) of Raphanus sativus, which are usually discarded were found to possess potent antioxidant and radical scavenging activity, as measured by standard antioxidant assays. Methanolic and acetone extracts of R. sativus leaves had total polyphenolic content of 86.16 and 78.77 mg/g dry extract, which were comparable to the traditional rich sources such as green tea and black tea. HPLC identification of polyphenolics indicated the presence of catechin, protocatechuic acid, syringic acid, vanillic acid, ferulic acid, sinapic acid, o-coumaric acid, myricetin, and quercetin in leaves and stem. Among the different extraction solvents, methanolic extract of leaves and stem showed potent reductive capacity, significantly inhibited linoleic acid peroxidation and displayed metal chelating activity. Further, they scavenged free radicals effectively with IC₅₀ (half maximal inhibitory concentration) of 31 and 42 μg/ml for DPPH radical, 23 and 52 μg/ml for superoxide radical, 67 and 197 μg/ml for hydrogen peroxide, and 56 and 62 μg/ml for nitric oxide, respectively. Leaves showed most potent antioxidant and radical scavenging activity as compared to stem, which may be accounted for the high polyphenolic content. Leaves and stem of R. sativus, often under-utilized part of this vegetable, thus possessed considerable amount of polyphenolics. Hence, it should be regarded as a potential source of natural antioxidants and could be effectively employed as an ingredient in health or in functional food.     

椰子种皮油提取物的抗氧化活性研究

测定椰子种皮油提取物中的总酚含量,对羟基自由基、DPPH（1,1-二苯基-2-三硝基苯肼）自由基、ABTS（2,2连氮-双-（3-乙基苯并噻咪唑-6-磺酸）自由基清除能力和总抗氧化能力等抗氧化活性指标。结果表明,椰子种皮油提取物中含有较高的总酚含量（68 mg/g）,提取物浓度为0.1 mg/mL时对羟基自由基的清除率为56.89％,对DPPH自由基的清除率为71.0％,对ABTS自由基的清除率为96.4％,表明椰子种皮油提取物具有很好的抗氧化活性。     

非洲楝提取物对斜纹夜蛾的杀虫活性研究

室内测定了非洲楝提取物对斜纹夜蛾幼虫的杀虫活性。结果显示,非洲楝提取物对斜纹夜蛾幼虫具有很强的毒杀作用,10和14 d的LC50值分别为0.466和0.173 mg/mL;此外,非洲楝提取物对斜纹夜蛾幼虫还表现出较强的抑制生长发育作用,与对照相比,幼虫龄期和蛹期延长,蛹重减小,化蛹率和成虫羽化率显著降低。非洲楝具有防治斜纹夜蛾的潜力。