青稞麸皮油提取工艺优化及其抑制α-葡萄糖苷酶活性研究

本研究以正己烷为溶剂,通过优化提取工艺增加青稞麸皮中油脂的提取率,随后通过扫描电镜探究超声辅助提取对青稞麸皮结构的影响,之后对青稞麸皮油的体外α-葡萄糖苷酶抑制能力和酶抑制作用类型进行研究。结果表明：在提取工艺为超声时间30min,超声功率225w,超声温度30℃,浸提时间12h,提取率可达到3.62%。通过体外α-葡萄糖苷酶抑制实验表明青稞麸皮油的抑制作用强于市售的阿卡波糖,IC₅₀值为0.736 mg/mL。相较于乙酸乙酯、乙醇作为提取溶剂,正己烷的抑酶效果强于其他溶剂。通过酶动力学实验分析,青稞麸皮油的抑制类型属于混合竞争型抑制。该文为青稞麸皮油作为α-葡萄糖苷酶抑制剂的开发提供了参考。     

板栗壳乙酸乙酯提取物活性研究及其化合物结构分析

为了研究板栗壳乙酸乙酯提取物体外活性,并分析其活性成分,依次采用DPPH法、ABTS法测定板栗壳乙酸乙酯提取物的抗氧化活性;PNPG法测定其体外抑制α-葡萄糖苷酶活性;超高效液相色谱—质谱联用技术(UPLC—MS/MS)对其成分进行分析。结果表明:板栗壳乙酸乙酯提取物具有较强的清除DPPH自由基、ABTS自由基的能力且可显著地抑制α-葡萄糖苷酶的活性,其有效成分主要为脂溶性黄酮类化合物。     

刺槐籽油中脂肪酸组成和不皂化物的GC—MS分析

用正己烷抽提刺槐籽油,样品经皂化和甲酯化后,用气相色谱-质谱联用法（GC—MS）测定了刺槐籽油的脂肪酸和不皂化物组成,共鉴定出7种脂肪酸和15种不皂化物,其中不饱和脂肪酸相对含量较高,主要为亚油酸和亚麻酸,其相对含量分别为62．99％和21．88％。刺槐籽油不皂化物中植物甾醇含量很高,γ-谷甾醇含量达40．33％。     

芭蕉的α-葡萄糖苷酶抑制活性

利用体外α-葡萄糖苷酶抑制模型对芭蕉花与根提取物进行活性评价,并与阳性对照Acarbose比较,发现芭蕉花与根提取物均能抑制α-葡萄糖苷酶活性。除芭蕉花的乙酸乙酯和正丁醇提取物外,其他提取物活性均远大于阳性对照Acarbose(IC50=1103.01μg·mL-1)。其中,芭蕉根和花的石油醚提取物的活性最高(IC50=32.03μg·mL-1和49.37μg·mL-1)。不同部位比较,芭蕉根的α-葡萄糖苷酶抑制活性好于花;同一部位不同溶剂的提取物比较,石油醚提取物α-葡萄糖苷酶抑制活性高于乙酸乙酯和正丁醇提取物。     

大白栓菌降糖活性部位筛选

目的:研究大白栓菌提取物的降糖活性,筛选其降血糖的活性部位。方法:用肾上腺素致高血糖小鼠模型评价大白栓菌乙醇提取物不同萃取部位的降糖效果;对活性更好的乙酸乙酯部位采用四氧嘧啶糖尿病高血糖小鼠模型进行验证,测定血糖水平、胰岛素水平,并计算胰岛素敏感性指标ISI,同时测定乙酸乙酯部位的α-葡萄糖苷酶抑制活性。结果:大白栓菌乙醇提取物不同萃取部位高、低剂量组与模型组血糖值有显著性差异;乙酸乙酯部位高、中、低剂量组与模型组血糖值有显著性差异;乙酸乙酯部位对酵母α-葡萄糖苷酶有抑制活性,但对大鼠α-葡萄糖苷酶无抑制活性。结论:大白栓各萃取部位都具有降糖作用,其中乙酸乙酯部位最好;乙酸乙酯部位对大鼠α-葡萄糖苷酶无抑制活性,其降糖机制可能与提高胰岛素敏感性有关。     

基于α-葡萄糖苷酶抑制活性评价青稞全粉提取物抑制效果及其相互作用

青稞是我国青藏高原地区特有的粮食作物,具有良好的改善血糖代谢功效,但其具体降糖活性成分以及它们之间的配伍关系尚未明确。以青稞全粉为研究对象,提取青稞全粉中的多酚、多糖、多肽三种关键活性成分,探究青稞全粉提取物对α-葡萄糖苷酶的抑制能力及其相互作用。通过单因素实验以及Box-Benhnken响应面优化实验,确定了利用微孔板法测定α-葡萄糖苷酶抑制活性的最佳反应体系,即酶浓度0.5 U/mL、缓冲液浓度80 mmol/L、底物浓度5 mmol/L。三种青稞全粉提取物均具有一定的α-葡萄糖苷酶抑制活性,其中青稞多酚的抑制活性最强,α-葡萄糖苷酶活性抑制率达到83.63%±2.92%,对应的IC50值为0.18 mg/mL。三种青稞全粉提取物两两复配均具有一定的协同增效作用。结果可为血糖控制人群的膳食选择和功能性食品的复配开发提供理论指导。     

6种栽培品种南瓜提取物的α-葡萄糖苷酶抑制活性的研究

目的:对6种不同栽培品种南瓜(金钩、甜面、日本、辽宁新民金钩、超甜蜜本、蜜本)提取物α-葡萄糖苷酶抑制活性进行研究。方法:通过建立体外α-葡萄糖苷酶抑制模型,对南瓜提取物进行活性筛选,并对提取物浓度与抑制活性关系进行研究。结果:6种栽培品种南瓜不同溶剂提取物均有一定的α-葡萄糖苷酶抑制活性,其中,金钩南瓜石油醚提取物的抑制活性最好(IC50=143.91μg/mL),活性远大于阳性对照阿卡波糖(IC50=1103.01μg/mL)。不同溶剂提取物显示石油醚提取物抑制活性均高于乙酸乙酯提取物和甲醇提取物。结论:6种栽培品种南瓜提取物均有一定的α-葡萄糖苷酶抑制活性,但不同品种其抑制活性具有一定的差别。     

药食两用中药中α-葡萄糖苷酶抑制剂的高通量筛选

目的:从72种药食两用中药中高通量筛选α-葡萄糖苷酶抑制剂。方法:采用α-葡萄糖苷酶抑制剂的体外高通量筛选模型,以对-硝基苯基-α-D-吡喃葡萄糖苷(PNPG)为底物,通过高效液相色谱分析水解产物中的对-硝基酚(PNP),进行α-葡萄糖苷酶抑制活性筛选。结果:在样品终浓度0.625mg/mL反应体系下,大多数的提取物对α-葡萄糖苷酶均具有一定的抑制作用,其中16个提取物的α-葡萄糖苷酶抑制活性达到100%。结论:所采用的筛选模型可实现α-葡萄糖苷酶抑制剂的高通量筛选,并且某些药食两用中药能显著抑制α-葡萄糖苷酶活性,对糖尿病的防治具有重要意义。     

麦麸皮提取物对α-葡萄糖苷酶的抑制活性研究

为深度开发麦麸资源,考察3种麦麸皮提取物对酵母和鼠源α-葡萄糖苷酶活性的抑制作用,结果显示:水、95%乙醇、乙酸乙酯提取物的得率分别为12.24%、3.49%、1.44%,组间差异具有统计学意义(P<0.01).0.3mg/mL 提取物对2种来源酶的抑制效果不同,抑制率分别为44.5%、56.4%、31.9%和26.3%、32.6%、26.8%,其半抑制浓度(IC50)分别为0.32、0.25、0.80和0.77、0.52、0.89mg/mL.选取抑制活性较好的95%乙醇提取物,针对与人体情况更为接近的鼠源α-葡萄糖苷酶,进一步考察其作用浓度和时间对抑制活性的影响,以及其抑制类型.结果表明:麦麸皮95%乙醇提取物是α-葡萄糖苷酶的竞争性抑制剂,抑制作用迅速,并呈现一定的剂量依赖关系.     

簕菜提取物及其化学成分对α-葡萄糖苷酶的抑制作用

试验采用以对硝基苯-α-D-吡喃葡萄糖苷(PNPG)为底物的酶抑制剂筛选模型测定了簕菜提取物及其化学成分对α-葡萄糖苷酶的抑制作用,为簕菜降血糖作用提供试验证据。试验结果表明,不同部位的簕菜中的抑制α-葡萄糖苷酶的活性物质都可以通过有机溶剂萃取步骤进行浓缩;簕菜叶、茎和根的乙酸乙酯层都表现出最高的抑制活性;簕菜乙酸乙酯层的9个萜类和6个多酚类化学成分中,二萜化合物ent-kaur-15-en-17-al-19-oic acid和多酚化合物异绿原酸C具有最好的抑制α-葡萄糖苷酶的活性,均高于对照品阿卡波糖,它们可能是簕菜提取物具有抑制α-葡萄糖苷酶活性的作用成分。     

光皮树籽抽出物的成分分析

为了分析光皮树籽抽提物的化学成分,采用无水乙醇、丙酮、正己烷、石油醚和乙酸乙酯分别抽提光皮树籽,抽出物经活性炭脱色后进行GC-MS 分析。结果发现,无水乙醇和丙酮抽出物中主要含有游离的棕榈酸、油酸和亚油酸,其中亚油酸相对含量最高,达到52% 以上,油酸相对含量最低,不超过8.2%。正己烷、石油醚和乙酸乙酯抽出物中甘三酯的脂肪酸组成主要是棕榈酸、硬脂酸、油酸和亚油酸,其中油酸相对含量最高,达到42% 以上,其次是亚油酸,总不饱和脂肪酸相对含量超过70%。抽出物中未发现三不饱和脂肪酸。     

In vitro inhibitory effect of oriental melon (Cucumis melo L. var. makuwa Makino) seed on key enzyme linked to type 2 diabetes: Assessment of anti-diabetic potential of functional food

As the world’s population continues to increase, the agricultural discards of plant origin have attracted considerable attention for various purposes in the pharmaceutical and food industry. The objective of present study was to evaluate the potential of oriental melon (Cucumis melo L. var. makuwa Makino) seed for management of hyperglycaemia-linked to type 2 diabetes. Ethanol and hexane extracts from oriental melon seed were used to evaluate their inhibitory activities against α-glucosidase and α-amylase. Low phenolic-containing hexane extract exhibited much higher inhibitory activities against α-glucosidase and α-amylase than ethanol extract. The GC–MS result revealed that hexane extract constituted linoleic acid (29.6%), oleic acid (17.3%), and palmitic acid (6.5%). At high concentration, hexane extract exhibited strong inhibitory activities against α-glucosidase (35.3%) and α-amylase (61.8%). These in vitro studies indicated that hexane extract of oriental melon seed could be used as a potent alternative for controlling type 2 diabetes.     

响应面试验优化超声辅助β-环糊精包合纯化美藤果油α-亚麻酸工艺

选用美藤果油为原料,采用β-环糊精包合法对其富含的α-亚麻酸进行提取纯化,并辅以超声波技术提升包合作用的效果。在单因素试验结果的基础上,利用Box-Behnken模型进行试验设计,以包合温度、超声波时间和β-环糊精-(混合脂肪酸+无水乙醇)质量比为考察因素,α-亚麻酸含量为指标,通过对数据的响应面处理分析及实验验证,得出了美藤果油中α-亚麻酸提取的最佳工艺条件为包合温度60℃、超声波时间73 min、β-环糊精-(混合脂肪酸+无水乙醇)质量比7.4∶1,此条件下得到的α-亚麻酸含量为59.16%。实验对α-亚麻酸生产新的来源途径进行了探索,通过优化条件为实际生产提供了理论依据。     

β-谷甾醇微胶囊工艺优化及抗油脂氧化研究

以β- 环糊精为壁材制备β- 谷甾醇微胶囊,通过正交试验研究微胶囊化最佳工艺条件,比较不同抗氧化剂和微胶囊化前后甾醇对猪油的抗氧化作用。结果表明,β- 环糊精制备β- 谷甾醇微胶囊最佳工艺条件是加水量60mL、搅拌温度50℃、搅拌时间50min、β- 谷甾醇体积与β- 环糊精质量比为1:10(mL/g),在此条件下包埋率为87.98%。微胶囊β- 谷甾醇对猪油具有较强的抗氧化能力,其抗氧化效果优于未包埋的β- 谷甾醇和VE;随着甾醇添加量的增加,抗氧化能力增强。     

Radical scavenging and reducing properties of extracts of cashew shoots (Anacardium occidentale)

The total phenolic content and antioxidant activities of methanol, hexane and ethyl acetate extracts of the shoots of Anacardium occidentale were measured. Total phenolic content was assessed by the Folin–Ciocalteau assay whereas antioxidant activities were assessed by measuring the ability of the extracts to scavenge the ABTS^·+ and DPPH^· radicals, superoxide anion radicals and nitric oxide radicals as well as their ability to reduce ferric ions. Results indicated that the methanol extract of A. occidentale was the most potent reducing agent and radical-scavengers compared to the other two extracts. The ethyl acetate extract exhibited some antioxidant activities whereas the hexane extract is the least reactive. The order of the antioxidant potency of the plant extract is methanol > ethyl acetate > hexane. The methanol extract contained more than 7 fold of total phenolic content compared to the hexane and ethyl acetate extracts indicating the likely possibility that the observed antioxidant activities were partly contributed by the phenolics. The results suggest that the shoots of A. occidentale are a source of natural antioxidants.     

Biological activity and composition of extract from aerial root of Ficus microcarpa L. fil.

Total phenolic content, antioxidant and antibacterial activities of Ficus microcarpa aerial roots were determined on methanol extract and its sub-fractions (hexane, ethyl acetate, n -butanol and water). The ethyl acetate fraction possessed the highest amount of phenolic compounds evaluated by Folin-Ciocalteu reagent method. It also showed the highest antioxidant activity when tested the following methods: DPPH, ABTS⁺ radical-scavenging, superoxide radical scavenging, reducing power and β -carotene linoleic acid bleaching. On the other hand, high phenolics content extracts (ethyl acetate, methanol and n -butanol) showed significantly higher inhibitory activity than low phenolics content extracts (water and hexane) against five tested Gram positive and Gram negative bacteria. Protocatechuic acid, catechol, p -vinylguaiacol, syringol, p -propylphenol, vanillin, p -propylguaiacol, isovanillic acid, 4- n -Propylresorcinol, syringaldehyde and oleanolic acid contained in ethyl acetate fraction were identified by GC-MS and HPLC based on their cochromatography with standard compounds. Protocatechuic acid, catechol and syringol exhibited nearly same antioxidant activity as did by positive control Trolox using the mentioned assays. Results here showed that the ethyl acetate fraction has strong antioxidant and antibacterial activities, which are correlated with its high level of phenolic compounds.     

玉米萌发过程中淀粉酶性质的研究

本实验研究了玉米萌发过程中各种因素对其中所含淀粉酶活力的影响,并研究了最佳萌发条件下,总淀粉酶、α-淀粉酶和β-淀粉酶活力的变化情况,通过SDS-PAGE凝胶电泳确定了α-淀粉酶和β-淀粉酶的分子量,以SephadexG-100色谱对两种酶进行了分离。结果表明,水分含量、温度、光照以及赤霉素等因素对玉米淀粉酶活力均有影响,在水分35%、温度30℃、赤霉素30mg/L和自然光照条件下萌发,玉米的淀粉酶活力最高;在萌发过程中,α-淀粉酶活力增加得比较缓慢,而且活力也大大低于β-淀粉酶,总淀粉酶和β-淀粉酶活力上升都比较迅速;β-淀粉酶的分子量为189.82×103D,α-淀粉酶的分子量为54.26×103D。     

甘草酸提取废液α-葡萄糖苷酶抑制剂的筛选与鉴定

将甘草酸提取废液用正己烷、氯仿、乙酸乙酯、正丁醇进行梯度萃取,检测各萃取相对α-葡萄糖苷酶的 抑制作用,筛选出活性最强的萃取相;根据双倒数曲线图判断其对α-葡萄糖苷酶的抑制作用类型,采用联合作用 指数分析其与阿卡波糖的协同作用;通过超高效液相色谱-二极管阵列检测-质谱检测方法分析,结合酸水解以及与 标准品相对照的方法,初步鉴定其主要成分的化学结构,并测定主要成分的含量。结果表明：在甘草酸提取废液 各溶剂萃取物中,乙酸乙酯萃取相对α-葡萄糖苷酶的抑制作用最强,为竞争性抑制,半抑制浓度为0.152 9 g/L,抑 制常数Ki为0.085 1 g/L;与阿卡波糖有协同抑制效应;其主要成分为甘草素、柚皮素、异甘草素以及芒柄花素的单 糖苷和二糖苷。甘草素类、柚皮素类、异甘草素类和芒柄花素类的黄酮含量总计分别为28.08%、2.95%、11.80%和 4.38%;黄酮总含量为47.21%。     

Identification of antioxidant components and fatty acid profiles of the leaves and fruits from Averrhoa carambola

The antioxidant compounds of leaves and fruits from Averrhoa carambola were extracted with acetone:water (7:3, v/v) and distilled water. The acetone:water extracts (AWE) were separated into five different subfractions, three obtained by liquid–liquid extraction using n-hexane (HF), ethyl acetate (EAF) and water (WF), and the other two obtained by further fractionation of the WF on a Sephadex LH-20 column (WS1 and WS2). The antioxidant activities, total phenolics and total flavonoids of these extracts and fractions were investigated. Results showed that all the extracts and fractions possessed potent antioxidant activities, as measured by DPPH, ABTS and FRAP methods, with the strongest for WS2 fractions accompanied with the highest total phenolics and total flavonoids. Reversed-phase HPLC, normal-phase HPLC, MALDI-TOF-MS and ¹³C NMR analyses identified that the main antioxidant components present in WS2 fractions were essentially of procyanidin-type proanthocyanidins, consisting mainly of epicatechin units linked by B-type interflavan bonds. In addition, GC–MS analysis revealed that the most abundant fatty acids were α-linolenic acid (62.04 ± 1.65%) for leaves and oleic acid (55.44 ± 1.37%) for fruits. The amount of total unsaturated fatty acids in leaves and fruits comprised more than 77% of total fatty acid.     

苦荞在萌发过程中营养物质的变化及其营养评价

通过测定萌发过程中苦荞的蛋白质、脂肪、脂肪酸、氨基酸、总糖、还原糖、α-、β-淀粉酶活性、矿物质元素、VB1和VB2的含量,研究萌发处理对苦荞营养价值的影响。结果表明：萌发过程中,蛋白质和脂肪等大分子物质均呈下降趋势;但可溶性低分子糖类、含氮物质和脂肪酸等小分子物质含量有较大提高,其中还原糖含量上升1.61%～10.63%,总氨基酸含量增加了3.85%,且7 种必需氨基酸含量均呈现上升趋势,赖氨酸增幅最大（30.5%）。与未萌发苦荞相比,VB1、VB2含量变化不大;同时,随着萌发过程的延长,α-、β-淀粉酶活性不断增强。萌发过程中,必需氨基酸/总氨基酸比值和必需氨基酸指数增加,必需氨基酸组成模式更加符合联合国粮食及农业组织/世界卫生组织（FAO/WHO）联合食品标准计划,第一限制氨基酸由赖氨酸转变为蛋氨酸＋胱氨酸。