Evaluation of bioactive flavonoids in Citri Reticulatae Pericarpium from different regions and its association with antioxidant andα-glucosidase inhibitory activities

Background:To explore the differences of 14 batches of Citri Reticulatae Pericarpium from different regions.Methods:The main aim of this study was to develop a high-performance liquid chromatography method-photodiode array detection for determining the contents of five flavonoids and the chromatographic fingerprints of Citri Reticulatae Pericarpium from different regions.Theα-glucosidase inhibitory activities and antioxidant properties of Citri Reticulatae Pericarpium,based on free-radical scavenging assays against 1,1-diphenyl-2-picrylhydrazyl,2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),and hydroxyl radicals,were estimated and compared.Results:Among the tested compounds,the content of hesperidin(13.386-68.235 mg/g)was the highest and that of hesperitin(0.045-0.277 mg/g)was the lowest.In comparing different sources of Citri Reticulatae Pericarpium,the contents of narirutin in Citri Reticulatae Pericarpium from Guangdong(0.824-0.851 mg/g)and Sichuan(1.069-1.204 mg/g)provinces of China were lower than in other provinces.In contrast,nobiletin(8.429-12.237 mg/g)and tangeretin(3.947-4.613 mg/g)were most abundant in Guangdong sources of Citri Reticulatae Pericarpium,followed by samples from Sichuan Province(nobiletin:6.761-7.658 mg/g;tangeretin:3.422-3.933 mg/g).Correlation analysis showed that nobiletin and tangeretin were the main contributors to the antioxidant capacity,and narirutin was the main active component inhibiting theα-glucosidase activity of Citri Reticulatae Pericarpium.Conclusion:This work revealed that the intrinsic quality of Citri Reticulatae Pericarpium was affected by different growing regions,which provides a scientific basis for controlling the quality of Citri Reticulatae Pericarpium and rationally developing and utilizing Citri Reticulatae Pericarpium.

Cucurbitane-Type Triterpene Glycosides from Momordica charantia and Their α-Glucosidase Inhibitory Activities

Ten cucurbitane-type triterpene glycosides,including five new compounds named charantosides H(1),J(2),K(3),momor-characoside A(4),goyaglycoside-l(5),and five known compounds(6-10),were isolated from the EtOAc extract of Momor-dica charantia fruits.The chemical structures of these compounds were identified by 1D and 2D NMR and HRESIMS spectroscopic analyses.Configurations of new compounds were determined by ROESY correlations and comparison of their 13C NMR data with literature reported values.All compounds were evaluated for their inhibition againstα-glucosidase,in which compounds 2,5,7,8,9 showed moderate inhibitory activities with IC50 values ranging from 28.40 to 63.26μM comparing with the positive control(acarbose,IC5087.65±6.51μM).

α-Glucosidase inhibitors isolated from medicinal plants

Objective:α-Glucosidase inhibitors can be used as a new class of antidiabetic drug.By competitively inhibiting glycosidase activity,these inhibitors help to prevent the fast breakdown of sugars and thereby control the blood sugar level.This study provides a wealth of information aboutα-glucosidase inhibitors isolated from medicinal plants;this knowledge will be useful in finding more potent antidiabetic candidates from the natural resources for the clinical development of antidiabetic therapeutics.Results:411 compounds exhibitingα-glucosidase inhibitory activity were summarized and isolated them from medicinal plants.The compound classes isolated include:terpenes(61)from 14 genus,alkaloids(37)from 11 genus,quinines(49)from 4 genus,flavonoids(103)from 24 genus,phenols(37)from 9 genus,phenylpropanoids(73)from 20 genus,sterides(8)from 5 genus,and other types of compounds(43).Conclusion:Compounds withα-glucosidase inhibitory activity are abundant in nature and can be obtained from several sources.They have highα-glucosidase inhibitory potential,and can be clinically developed for treating diabetes mellitus.

α-Glucosidase inhibitor produced by an endophytic fungus, Xylariaceae sp. QGS 01 from Quercus gilva Blume

Xylariaceae sp.QGS 01,an endophytic fungus isolated from the stem of Quercus gilva Blume showed high-glucosidase inhibitory activity.α-Glucosidase inhibitor have the role as one of carbohydrate-hydrolyzing enzymes to postpone absorption of glucose in the digestive organs.The α-glucosidase inhibitor constituents were isolated from the ethyl acetate extract of the mycellium of endophytic fungi Xylariaceae sp.QGS 01 using a bioassay-guided fractionation technique.Further separation and purification of the active fraction led to the isolation of constituents with strong inhibitory activities against-glucosidase:8-hydroxy-6,7-dimethoxy-3-methylisocoumarine(1)with inhibitory concentration(IC50)values against-glucosidase from Saccharomyces cerevisiae of 41.75μg/mL,while quercetin as the standard had an IC50 value of 4.80g/mL.The results of the present study showed that the endophytic fungus Xylariaceae sp.QGS 01 is potentially a rich source of antidiabetic medicine.

α-Glucosidase Inhibition by New Schiff Base Complexes of Zn(II)

There are many reports that divalent alkaline earth, first-row transition metals, and Zn(II) ions have α-glucosidase inhibitory effects. Cu(II) and Zn(II) ions, in particular, have strong α-glucosidase inhibitory effects. Several Schiff bases also display α-glucosidase inhibitory effects. In this study, we focused on safe and highly effective complexes including Zn(II) ion. We prepared and characterized the Zn(II) complexes with four different Schiff bases (N-salicylidene-β-alanine (N-sβ), N-N’-bis (salicylidene) ethylenediamine (N-bsE), N, N’-bis (salicylidene)-phenylenediamine (N-bsP), and 1-[(2-dimethylaminoethylimino) methyl]naphtholate (DMN)) and investigated their α-glucosidase inhibitory effects in vitro, using α-glycosidases from Saccharomyces sp. and rat small intestine, and in vivo, using a sucrose tolerance test. The Zn(II) complexes with DMN showed the highest in vitro and in vivo α-glucosidase inhibitory effects in this study.

不同提取方法对沙棘叶茶活性成分含量、抗氧化能力及α-糖苷酶抑制活性的影响

该文分别以水和60%乙醇为提取溶剂,在55、75℃和95℃下对沙棘叶茶整叶和沙棘叶茶粉进行提取,比较提取物中总黄酮、可溶性总多酚、异鼠李素含量及抗氧化能力和α-糖苷酶抑制能力。结果表明,提取溶剂为60%乙醇、提取温度为95℃时,沙棘叶茶粉提取物中的活性成分含量最高,总黄酮、可溶性总多酚、异鼠李素含量分别为(82.59±1.80)、(117.02±1.93)、(1.592±0.074)mg/g,清除DPPH自由基、羟基自由基和亚硝酸根的能力最强,其EC_(50)值分别为(0.1419±0.0006)、(0.3571±0.0048)、(0.8156±0.0013)mg/g,还原力最高为(118.65±2.40)mg/g,α-糖苷酶抑制能力最强,IC50值为(0.3930±0.0101)mg/g。通过主成分分析,该提取物的样品评分最高。

A Study on the Inhibitory Potency of Protease Inhibitorsin Porcine Colostrum

Porcine colostrum and milk were separated into the acid-soluble fraction(SF)and casein fraction(CF)by centrifuge. Trypsin and chymotrypsin inhibitory capacity in porcine colostrum, milk and their components were determined by incubating bovine trypsin or chymotrypsin in a medium. The inhibition of insulin-like growth factor I(IGF-I)and epidermal growth factor(EGF)degradation in pig small intestinal contents by porcine colostrum was measured by incubating iodinated IGF-I or EGF. Degradation of labeled IGF-I or EGF was determined by monitoring the generation of radioactivity soluble in 30% trichloroacetic acid(TCA). The results showed that porcine colostrum had high levels of trypsin and chymotrypsin inhibitory activity and increased the stability of IGF-I and EGF in pig intestinal contents. The SF was higher in inhibitory potency than CF. The present study revealed that the protease inhibitors in porcine colostrum, milk-derived and colostrum-specific, existed mainly in SF.

大兴安岭地区蓝果忍冬果实多酚鉴定及生物活性分析

以大兴安岭6个地区(加格达奇、新林、宏伟、阿木尔、图强和塔河)的蓝果忍冬果实为研究对象,测定并比较其总酚含量及总花色苷含量的不同;使用3种不同抗氧化方法全面分析其抗氧化活性;通过测定其对α-淀粉酶和α-葡萄糖苷酶的半抑制活性评价其降血糖活性;对其果实多酚粗提液进行分离纯化,并对不同组分进行定性定量分析。结果表明,这6个地区的蓝果忍冬果实总酚含量和总花色苷含量有明显差异,但组成基本相同,均具有较高的抗氧化活性;对α-淀粉酶、α-葡萄糖苷酶有一定抑制效果。表明这6个地区蓝果忍冬果实有开发利用的潜能。

干燥方式对三七叶主要活性成分、体外抗氧化、α-葡萄糖苷酶抑制活性、挥发性成分和代谢物的影响

为选择较好的三七叶干燥方式,分别采用热风干燥、热泵干燥、真空干燥3种方式对三七叶进行干燥,测定不同干燥方式下三七叶的总皂苷、多糖、总酚和总黄酮含量以及单体皂苷含量,评估其体外抗氧化和α-葡萄糖苷酶抑制能力,采用气相色谱-离子迁移谱联用技术鉴定其挥发性成分,并采用非靶向代谢组学技术分析其代谢物变化。结果表明:3种干燥方式均可明显提高三七叶的总皂苷和多糖含量,降低其总酚和总黄酮含量,但均不同程度地减弱了其功能活性;其中热泵干燥组的总皂苷和多糖含量最高,并具有最强的1,1-二苯基-2-三硝基苯肼自由基清除能力和α-葡萄糖苷酶抑制能力,以及较强的2,2’-联氮-双-3-乙基苯并噻唑啉-6-磺酸阳离子自由基清除能力和铁还原能力;高效液相色谱分析发现热泵干燥显著降低了三七叶中三七皂苷Fc、Fe的含量,而真空干燥组与之相反;从三七叶中共检测出85种挥发性成分,其中热泵干燥组的醇类和醛类化合物相对含量最高,而酮类化合物相对含量最低,且不同处理组之间有明显区别;采用超高效液相色谱-四极杆-轨道阱质谱联用技术从热泵干燥前后的三七叶中鉴定出659种代谢物,其中有113种和68种代谢物分别在正、负离子模式下表达显著上调,98种和31种代谢物分别在正、负离子模式下表达显著下调,主要包括脂质和类脂分子、有机杂环化合物、有机酸及其衍生物等。针对三七叶中24种皂苷类代谢物进行进一步分析,发现其中7种相对含量显著降低、1种相对含量显著升高,这也印证了高效液相色谱的测定结果;对差异代谢物进行京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析,发现新鲜三七叶在热泵干燥过程中最可能存在的代谢通路有氨基酸的生物合成、2-氧羧酸代谢及辅助因子的生物合成。综上,热泵干燥对三七叶的化学成分和功能活性具有最好的保持效果,较适合用于三七叶的干燥,其可通过多个作用途径改变三七叶的代谢物组成,并影响其挥发性成分含量。

小米多肽酶解工艺及其抗氧化和ACE抑制活性

以小米蛋白为原料,制备具有抗氧化活性和血管紧张素转移酶(ACE)抑制活性的食源性多肽。采用碱性蛋白酶、中性蛋白酶和风味蛋白酶酶解小米蛋白,选取最优酶解工艺。选用碱性蛋白酶酶解4 h,得到的蛋白水解液分别通过3 ku和10 ku的超滤膜,得到分子质量<3,3~10 ku和>10 ku的3种组分,测定其抗氧化活性和ACE抑制活性。结果表明:采用碱性蛋白酶酶解4 h得到的蛋白水解液经超滤后得到分子质量<3 ku的多肽具有最高的抗氧化活性和ACE抑制活性,其DPPH清除能力为38.44%,ABTS自由基清除能力为81.62%,羟基自由基清除能力为68.49%,ACE抑制活性为87.53%。此方法得到的多肽分子质量小,功能氨基酸含量较高,具有良好的抗氧化活性和ACE抑制活性。本研究结果为抗氧化肽和ACE抑制肽的开发提供试验依据,对未来工业化的发展提供理论参考。

Flavonoids from Litchi(Litchi chinensis Sonn.) Seeds and Their Inhibitory Activities on α-Glucosidase

With the bioactivity-guided method,a new flavanone glycoside,together with nine known flavonoids were isolated from 50% aqueous ethanol of litchi（Litchi chinensis Sonn.） seeds.The chemical structure of the new compound was elucidated via 1D and 2D nuclear magnetic resonance（NMR） techniques and mass spectrometry to be （2S）-pinocembrin-7-O-（6＂-O-α-L-arabinosyl-β-D-glucopyranoside）（1）,and the nine known compounds were determined to be quercetin（2）,phlorhizin（3）,pinocembrin-7-O-glucoside（4）,kaempferol-7-O-β-D-glucopyranoside（5）,onychin（6）,nairutin（7）,narcissin（8）,pinocembrin-7-O-[（6＂-O-β-D-glucopyranoside）-β-D-glucopyranoside]（9） and pinocembrin-7-O-[（2＂,6＂-di-O-α-L-rhamnopyranosyl）-β-D-glucopyranoside]（10）.Some of the isolated flavonoids were tested for their inhibitory effects on α-glucosidase.And compounds 2 and 3 showed stronger inhibitory activity than positive control.

8种复方中药液的生物活性及体外抗氧化能力研究

试验旨在对比8种复方中药液中的生物活性物质含量和抗氧化能力。以紫外分光光度计法测定总多酚含量(以表儿茶素没食子酸酯计)和总黄酮含量(以芦丁计)。以维生素C为对照品,半数抑制浓度(IC50)为指标,用紫外分光光度法比较中药液清除DPPH自由基、ABTS自由基、超氧阴离子自由基的能力,考察生物活性物质含量与抗氧化能力的相关性。结果显示,8种复方中药液中PHBQC的总多酚最高,达8.27 mg/mL;YQH的总黄酮含量最高,达62.40 mg/mL。体外DPPH自由基清除能力最好的是YJL,IC50为0.007 mg/mL;体外ABTS自由基清除能力最好的是WWXDY,IC50为0.171 mg/mL;体外超氧阴离子自由基清除能力较好的是PHBQC,IC50为2.17 mg/mL。药液总多酚含量与DPPH自由基清除力、ABTS自由基清除力呈强相关性,与超氧阴离子自由基清除力呈中等相关性,总黄酮含量与DPPH自由基清除力、ABTS自由基清除力、超氧阴离子自由基清除力均呈强相关性。研究表明,可考虑将复方中药液的总多酚和总黄酮含量作为畜禽中药饲料添加剂的筛选指标。

Screening of probiotics with efficient α-glucosidase inhibitory ability and study on the structure and function of its extracellular polysaccharide

Inhibition ofα-glucosidase activity is an important strategy in lowering the concentration of blood sugar.In this paper,using domestic and foreign characteristic food-derived substances as the sources of lactobacillus,the performance of them were evaluated by measuring the strains’α-glucosidase inhibitory ability.Finally,the cell-free extracellular supernatants(CFS)of Lactobacillus rhamnosus LB1lac10 was determined to have the highest α-glucosidase inhibition ability.Based on the Nanopore third-generation sequencing technology platform,the genome of LB1lac10 was sequenced and functional gene annotation was performed.After that,the biological activity and structural composition of the exopolysaccharide produced by L.rhamnosus LB1lac10 were studied.The purified exopolysaccharide EPS1-1 also showed efficientα-glucosidase inhibitory ability.The structure and conformation characteristics of EPS1-1 were further analyzed.The EPS1-1 from L.rhamnosus LB1lac10 had a molecular weight of 88,650 Da,and it was mainly composed of mannose,glucuronic acid,glucose,xylose,galactose,and arabinose.From the FT-IR and NMR analyses,EPS1-1 had functional groups of a typical polysaccharide structure and contained two types of glycosidic bonds with α-configuration pyranose.The main glycosidic bond corresponded to→4)-α-D-Glcp-(1→,which might be an important reason why EPS1-1 could inhibit α-glycosidase.Thermodynamic studies showed that EPS1-1 had high heat resistance to meet the needs of food processing.The results suggested that L.rhamnosus LB1lac10 could be used as a potential probiotic to lower blood sugar,and the EPS1-1 has the potential to serve as a naturalα-glycosidase inhibitor to regulate the concentration of blood glucose.

补肾助孕汤对小鼠生殖能力影响的实验研究

目的探讨中药补肾助孕汤对小鼠生殖能力的影响。方法 60只昆明雌性小鼠随机分为实验组与对照组。实验组每天2次经鼠胃管灌注补肾助孕汤,对照组同时给予生理盐水灌胃,分别于给药10、20天处死小鼠,每次每组15只,放射免疫法检测血清雌二醇和孕酮水平;HE染色,行子宫、卵巢组织形态学观察;免疫组化法测定子宫内膜白血病抑制因子(leukaemia inhibitory factor,LIF)、表皮生长因子(epidermal growth factor,EGF)和降钙素(calcitionin,CT)表达。结果给药10、20天,实验组小鼠子宫、卵巢重量,血清雌二醇、孕酮水平以及子宫内膜LIF、EGF、CT表达均较对照组同期增加,差异有统计学意义(P<0.05,P<0.01),且以给药20天作用为优(P<0.05)。组织学检查显示,实验组小鼠卵巢各级卵泡数目增加,子宫内膜腺体数目增多,子宫内膜增生,复层排列,基质细胞增多,以给药20天最明显。结论补肾助孕汤可以促进小鼠生殖器官的发育,促进雌二醇、孕酮分泌及卵泡生长;增加子宫内膜的容受性,从而增强其生殖能力。

薄层色谱-生物自显影观察新疆两色金鸡菊中清除自由基和抑制α-葡萄糖苷酶活性成分

目的:采用薄层色谱-生物自显影技术(TLC-bioautography),观察新疆两色金鸡菊提取物中具有清除自由基和抑制α-葡萄糖苷酶活性成分.方法:以1,1'-二苯基苦基苯肼(DPPH)和2,2'-氨基-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐(ABTS)为显色剂,观察新疆两色金鸡菊水提物和醇提物中清除自由基的有效成分;以对硝基苯-β-D-葡萄糖苷(p-Nitrophanyl-β-D-Gluopyranoside,p NPG)为底物,观察水提物和醇提物中具有抑制α-葡萄糖苷酶(来源于啤酒酵母菌)的活性成分.采用混合标准物质TLC色谱进行活性成分定性分析.结果:新疆两色金鸡菊水提物和醇提物中均含有马里苷、奥卡宁、栎草亭-7-O-β-D-葡萄糖苷、黄酮奥卡宁(flavanokanin)、绿原酸、芦丁和槲皮素等化学成分.经薄层色谱-生物自显影实验,两色金鸡菊水提物和醇提物中的黄酮奥卡宁、马里苷、芦丁和绿原酸均有较强清除DPPH和ABTS自由基的能力;水提物和醇提物中黄酮奥卡宁、奥卡宁和马里苷能有效抑制α-葡萄糖苷酶的活性.结论:经薄层色谱-生物自显影技术可快速发现两色金鸡菊中具有清除自由基和抑制α-葡萄糖苷酶活性成分,为进一步研究提供了指引.

大海马ACE抑制肽制备及其抗氧化能力的测定

为了从大海马蛋白中制备出ACE抑制肽及分析肽的抗氧化能力,本文通过比较小分子肽与ACE间的关系对蛋白酶进行了选择,筛选出木瓜蛋白酶作为海马蛋白的水解酶。然后,在单因素实验基础上采用响应面法对木瓜蛋白酶制备ACE抑制肽的关键参数进行了优化,结果为酶底比(E/S)为5%、时间7.5 h、p H7.7、温度59℃,测得其水解度为20.41%±0.12%,ACEIPs的IC_(50)值为1.897±0.072 mg/m L。经Sephadex G-15分离纯化后,得到五个组分,其中第三个组分(PH-I3)、第4个组分(PH-I4)和第5个组分(PH-I5)的活性最好,IC_(50)分别为0.896、0.982、0.814 mg/m L;并对这五个组分进行了抗氧化实验,各组分均能显著的清除DPPH自由基、羟基自由基,具备与Fe2+的螯合能力。所以,由PH-I制备的ACE抑制肽同时具有降血压和抗氧化的功能,在功能性食品开发中具有重要的意义。

塔河南岸跃满区块三叠系防塌钻井液研究与应用

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