Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties.

Recent advances in research on vine tea,a potential and functional herbal tea with dihydromyricetin and myricetin as major bioactive compounds

Vine tea has been used as an herbal tea by several ethnic minorities for hundreds of years in China.Flavonoids,a kind of indispensable component in a variety of nutraceutical,pharmaceutical and cosmetic applications,are identified to be the major metabolites and bioactive ingredients in vine tea.Interestingly,vine tea exhibits a wide range of significant bioactivities including anti-oxidant,anti-inflammatory,anti-tumor,antidiabetic,neuroprotective and other activities,but no toxicity.These bioactivities,to some extent,enrich the understanding about the role of vine tea in disease prevention and therapy.The health benefits of vine tea,particularly dihydromyricetin and myricetin,are widely investigated.However,there is currently no comprehensive review available on vine tea.Therefore,this report summarizes the most recent studies investigating bioactive constituents,pharmacological effects and possible mechanisms of vine tea,which will provide a better understanding about the health benefits and preclinical assessment of novel application of vine tea.

Investigation of in vitro antioxidant activity of dihydromyricetin and flavonoids rich extract from vine tea(Ampelopsis grossedentata)

Background:Vine tea from fermented Ampelopsis grossedentata leaves has been used as a herbal tea and folk medicine in the southern region of China for hundreds of years.The aim of this investigation was to analyze the total flavonoids found in vine tea,including three bioactive flavonoids,and the total phenolic contents in the aqueous methanol extracts of 10 vine tea samples.In addition,this study also aimed to examine the antioxidant activity of dihydromyricetin and vine tea’s flavonoid-rich extract.Methods:The total flavonoids and total phenolic content assay of extracts from vine tea were performed by ultraviolet-visible spectroscopy and epoch microplate spectrophotometer,respectively.Three bioactive flavonoids were quantified simultaneously using high performance liquid chromatography.The antioxidant activity of dihydromyricetin and vine tea’s flavonoid-rich extract was evaluated in vitro using six different methods.Results:Vine tea contained a large number of flavonoids,with dihydromyricetin as its main constituent.The flavonoid-rich extract exhibited a significant scavenging effect on superoxide anion radicals,and on 3-ethylbenzthiazoline-6-sulphonic acid and 1,1-diphenyl-2-picrylhydrazyl radicals.It also possessed definite activity in lipid peroxidation inhibition,ferric reduction,and the moderation of Fe2+ion chelation ability.There was a significant negative correlation between dihydromyricetin content and antioxidant activity in the vine tea samples,including superoxide anion radical scavenging activity(P=−0.754,P<0.05),lipid peroxidation inhibition activity(P=−0.759,P<0.05),ferric-reducing antioxidant power(P=−0.843,P<0.01),respectively.Dihydromyricetin played a dominant role in the antioxidant activities of the flavonoid-rich extract.Conclusion:Vine tea’s flavonoid-rich extract could be used as a new antioxidant source to safeguard against oxidative stress.

Ensiling vine tea (Ampelopsis grossedentata) residue with Lactobacillus plantarum inoculant as an animal unconventional fodder

The study aimed to evaluate the application of silage fermentation in storing vine tea residue.Dynamic of fermentationrelated product,chemical component and bacterial community of silage with or without Lactobacillus plantarum F1inoculant were analyzed.The results showed that F1 treatment had a significant (P<0.05) impact on the lactic acid and ammoniacal nitrogen concentrations and pH value.Total phenols were well preserved in both treatments.After 30 days of ensiling,L.plantarum occupied the majority of Lactobacillus genus (more than 95%) in all silage samples.Spearman revealed a positive (P<0.01) correlation between lactic acid content and Lactobacillus.Overall,ensiling vine tea residue with L.plantarum can effectively preserve the nutritional attributes and total phenols,which offers a new insight into utilizing vine tea residue.

Relation of tea ingestion to salivary redox and flow rate in healthy subjects

The biochemistry of human saliva can be altered by food intake.The benefits of tea drinking were extensively studied but the influence of tea ingestion on human saliva has not been revealed.The work aimed to investigate the immediate and delayed effect of vine tea,oolong tea and black tea intake on certain salivary biochemistry and flow rate.The saliva samples of healthy subjects were collected before,after and 30 min after tea ingestion.The chemical compositions and antioxidant capacity of tea samples were analyzed to correlate with salivary parameters.Principal component analysis indicated that the effects of vine tea consumption were dominated by increasing salivary flow rate(SFR),production rate of total protein(TPC),thiol(SH),malondialdehyde,catalase activity and antioxidant capacity(FRAP)in saliva.The antioxidant profile of studied tea samples(FRAP,polyphenols,flavonoids)was positively correlated with salivary SFR,TPC,SH and FRAP but negatively correlated with salivary uric acid concentration in saliva.

莓茶黄酮提取物对粉葛淀粉结构和体外消化的影响

将莓茶黄酮提取物(VTE)加入粉葛淀粉(KS)中制备复合物,采用激光共聚焦扫描显微镜(CLSM)、傅里叶红外光谱(FT-IR)和X射线衍射(XRD)对复合物进行结构表征,通过体外消化模型预测复合物的消化性和血糖生成指数(GI)。结果表明:FT-IR和XRD图谱显示成功制备的复合物为A+V型复合物;CLSM图像检测证明VTE直接作用于KS;体外模拟消化试验结果显示,复合物的抗性淀粉(RS)含量较KS提高20.56%,预测GI为63.83±0.46,属于中GI食物。

不同加工工艺的莓茶风味品质差异分析

为系统揭示不同加工工艺的绿莓茶、黄莓茶、红莓茶风味品质差异,采用感官审评、理化成分检测、顶空固相微萃取结合气相色谱-质谱联用技术对这3种莓茶进行品质分析。感官审评结果表明,黄莓茶白霜满披、汤色黄亮、果香浓郁、滋味较醇和;绿莓茶干茶黄绿、汤色绿黄明亮、炒香浓郁、滋味微苦;红莓茶色泽红褐、汤色橙红明亮、花果香浓郁、滋味醇和。滋味品质成分分析显示,绿莓茶中可溶性糖、水浸出物、二氢杨梅素含量均比黄莓茶、红莓茶高;但红莓茶中游离氨基酸含量最高。香气组分分析结果表明,共鉴定到56种挥发性组分,绿莓茶、黄莓茶香气组分以烃类为主,而红莓茶以醇类为主;1,1,6-三甲基-1,2-二氢萘、石竹烯、月桂醇、芳樟醇与绿莓茶的炒香特征密切相关;而苯乙醛、萘、2-戊基呋喃、P-伞花烃、正十四烷与黄莓茶的果香特征密切相关;苯乙醛、水杨酸甲酯、1,1,6-三甲基-1,2-二氢萘则赋予了红莓茶花果香的特征属性。

显齿蛇葡萄资源及藤茶品质评价研究进展

藤茶是一种具有抗氧化、抗炎、抗肿瘤等多种生物活性的代用茶,由显齿蛇葡萄嫩茎叶制成,主要活性成分为黄酮、多酚、多糖类物质。藤茶产业已成为武陵山少数民族地区的特色农业产业。目前,由于原料植物显齿蛇葡萄种质资源、产地及生产加工过程存在差异,藤茶产业的质量控制标准缺乏,制约了藤茶产业健康有序发展。研究综述了有关藤茶品质的研究进展,包括藤茶的原料植物(显齿蛇葡萄)资源、活性化学成分分析及藤茶品质评价等内容,以期规范藤茶的生产加工,为完善质量标准提供参考。

藤茶及其活性成分二氢杨梅素的药理作用

中药藤茶为葡萄科蛇葡萄属藤本植物,含有黄酮类、酚类、甾体类等多种化学成分。其中,二氢杨梅素为藤茶中含量最高的黄酮类化合物,也是其发挥药效作用的主要成分。研究发现,藤茶及二氢杨梅素的抗肿瘤作用效果显著,其机制主要涉及诱导凋亡和抑制增殖、抑制迁移侵袭、调节免疫、逆转耐药。另外,藤茶及二氢杨梅素还可以通过抗氧化作用治疗心血管疾病、神经退行性疾病和肝病;通过抗炎作用治疗肠道炎症、关节炎、神经炎等炎症性疾病;通过调节代谢改善葡萄糖和脂质代谢紊乱。此外,藤茶及二氢杨梅素还具有抗菌、抗病毒等多种作用。文章对藤茶及其活性成分二氢杨梅素的药理作用进行整理综述,并分析总结其临床应用价值和安全性,以期为藤茶药用资源的开发利用提供科学依据。

藤茶传统炒青工艺条件优化及其香气成分HS-SPME-GC-MS分析

为优化藤茶传统炒青工艺条件,提高藤茶感官品质。通过单因素试验和Box-behnken中心组合设计试验,以感官评分为响应值对藤茶传统炒青工艺条件进行优化;采用HS-SPME-GC-MS法分析藤茶样品挥发性香气成分。结果表明,炒青优化工艺条件为炒青时间20 min,炒青温度210℃,揉捻时间31 min;优化工艺条件下所得藤茶样品共检测出七大类共33种挥发性香气物质,其中烯烃类物质10种、烷烃类6种、醇类4种、酮类1种、酯类3种、醛类2种、其他类7种(烷烃杂环化合物),其相对含量占比分别为22.4%,35.2%,4.3%,0.3%,16.0%,2.3%,19.5%。在检出的组分中β-紫罗兰酮、壬醛、反式-2-己烯醛、1-辛烯-3-醇属于藤茶的特征香气成分。这些成分构成了藤茶的花香和果香风味。藤茶传统炒青优化工艺条件可行,所得藤茶品质优良,可为藤茶深加工利用提供科学依据。

藤茶总黄酮对非酒精性脂肪性肝病模型小鼠肠道菌群的影响

目的探究藤茶总黄酮对高脂饮食诱导非酒精性脂肪肝(NAFLD)小鼠肠道菌群的影响。方法28只小鼠随机分为4组:空白对照组、模型对照组(HFD组)、藤茶总黄酮小剂量组(TF-L组)、藤茶总黄酮大剂量组(TF-H组),每组7只。HFD组、TF-L组、TF-H组小鼠接受高脂饲料喂养,空白对照组小鼠接受普通饲料喂养。在喂食高脂饲料12周后,TF-L组、TF-H组每天分别灌胃藤茶总黄酮溶液125和250 mg·kg^(-1)·d^(-1),连续6周。采用苏木精-伊红染色法(HE)观察小鼠肝脏和肠道组织病理状况,采用免疫组化法分析结肠黏膜上皮细胞间紧密连接蛋白的表达水平。采用酶联免疫吸附测定(ELISA)试剂盒检测小鼠血清炎症因子的含量。采用16S rRNA测序技术分析小鼠肠道菌群变化。结果藤茶总黄酮可有效改善小鼠肝脏和肠道病理学变化;降低血清炎症因子白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)的含量;促进结肠内紧密连接蛋白Occludin、ZO-1和Claudin 1表达。3组小鼠肠道菌群存在显著差异,藤茶总黄酮显著降低拟杆菌与厚壁杆菌的比值(P<0.05),增加粪杆菌属、嗜酸乳杆菌属和乳酸菌属的丰度,改善肠道菌群紊乱。结论藤茶总黄酮对高脂饮食引起的NAFLD具有一定改善作用,其机制可能与促进肠屏障的修复和改善肠道菌群紊乱有关。

不同冲泡时间和次数对藤茶活性成分的影响

为探究不同冲泡时间和次数对藤茶活性成分的影响,本研究测定了藤茶(茶水比1∶50)分别在沸水冲泡5 min、10 min、20 min、30 min、1 h、2 h、4 h、6 h、8 h、12 h、24 h和冲泡5次的(2R,3R)-二氢杨梅素、(2S,3S)-二氢杨梅素、花旗松素、杨梅苷、杨梅素、多酚、可溶性糖、水溶性浸出物含量,同时进行主成分分析。结果表明,(2R,3R)-二氢杨梅素、(2S,3S)-二氢杨梅素、花旗松素、多酚的含量随冲泡时间的增加均呈先升后降的趋势,含量最高时冲泡时间均为30 min;杨梅苷、可溶性糖的含量随冲泡时间的增加均呈先上升后逐渐趋于平缓的趋势,含量最高时冲泡时间分别为6 h、8 h;杨梅素的含量随冲泡时间的增加呈逐渐上升的趋势,含量最高时冲泡时间为24 h;7种活性成分和水溶性浸出物的含量均随冲泡次数的增加呈显著下降趋势;主成分分析共提取特征值大于1的主成分2个,方差累计贡献率98.225%,同时建立活性成分评价模型Y=0.761 79Y_(1)+0.220 45Y_(2)。藤茶冲泡时间为30 min时,活性成分综合评分最高,冲泡2次(每次25 min)时,多种活性成分溶出率达95%以上,本研究可为藤茶的科学饮用提供理论依据。

林下套种有机藤茶标准化栽培技术研究

茶产业是松阳县山区传统特色经济产业,也是维持山区林农主要经济来源的保证。但近几年茶产业所表现出来的茶叶良种更新缓慢、人工采摘成本增加、药肥的大量使用等问题,已严重影响到林农茶叶生产的积极性。本研究主要是引进和栽培作为药食同源的新食品茶饮资源-藤茶(Ampelopsis grossedentata),通过对林下有机藤茶的园地选择、整理、苗木培育、定植技术、田间管理、病虫害防治、采收等方面的标准化栽培技术研究,为探寻有机藤茶最佳栽培条件,推动藤茶产业发展提供技术支撑。

别样茶-藤茶的古今应用历史初步调查

对我国别样茶(Other Kinds of Tea)中藤茶的古今应用历史以及现代研究等方面进行调查,为进一步的深入研究和开发提供参考。藤茶在我国南方民间应用历史悠久,应用范围广泛,具有别样茶的特征。现代化学研究表明藤茶中主要含有黄酮类成分,以二氢杨梅素含量最高,药理活性研究表明藤茶具有消炎抗菌、抗肿瘤、保肝、降血糖降血脂等活性。因此藤茶是预防、防治慢性代谢性疾患非常有前景的一个研究对象。对藤茶进行深入整理研究,不仅能够对我国茶文化多样性研究起到推动作用,也能够为防治慢性代谢性疾病的新药开发提供线索。

藤茶总黄酮和二氢杨梅素的提取检测研究进展

藤茶系葡萄科蛇葡萄属中的1种野生藤本植物,也是典型的类茶植物,在我国分布广泛。研究发现,藤茶中总黄酮和二氢杨梅素含量较高,实属黄酮类化合物在植物体中分布的1种特例。藤茶的主要成分总黄酮和二氢杨梅素具有抗氧化、抗高血压、保肝护肝、抗肿瘤等多重功效。对藤茶总黄酮和二氢杨梅素已优化的提取方法及其检测方法进行综述,以期为深入研究藤茶总黄酮和二氢杨梅素提供理论参考。

藤茶感官特征定量描述分析与风味轮构建

采用感官定量描述分析法研究藤茶的感官风味特征,并绘制藤茶风味轮。研究结果表明,经培训的评茶小组确定了藤茶的5个外形描述词、5个汤色描述词、7个香气描述词、10个滋味描述词及其定义,之后通过方差分析(P<0.05)结合主成分分析(贡献率>80%),确定所列的27个藤茶感官描述词均可较好评价藤茶样品的感官品质,结合聚类分析进一步得出胶质感、鲜黄、草香、木香、槟榔香、花香、甘甜、回甘、清爽、刺喉感、粗钝感及生津是区分藤茶品质的主要感官特征属性,同时绘制出直观反映藤茶感官特征的风味轮。该研究为了解藤茶的风味品质及开发应用提供参考。

藤茶的功能性及黄酮类化合物提取研究进展

藤茶系葡萄科蛇葡萄属,为显齿蛇葡萄科的嫩茎叶,内富含多种生物功效成分,是具有很大开发潜力的野生植物资源。本文对藤茶的营养成分、主要化学成分进行了简要介绍,综合国内外研究报道,对藤茶植物的生物活性及其功效成分的提取方法进行了总结。为从事藤茶生理、药理功能研究及产品开发的相关人员提供参考。

藤茶总黄酮对人胃癌SGC-7901细胞增殖抑制作用的实验研究

目的探讨藤茶总黄酮的体外抗肿瘤作用。方法采用MTT法、生长曲线法、细胞集落形成法观察藤茶总黄酮对人胃癌SGC-7901细胞抑制作用。结果藤茶总黄酮能明显抑制体外培养的SGC-7901细胞的生长,MTT法IC50为20.71μg.ml-1;细胞生长曲线法提示其对SGC-7901细胞的生长也有明显的抑制作用;集落形成法,当药物浓度在9.90μg.ml-1以上时抑制率为100%,当药物浓度为6.60μg.ml-1时抑制率为69.80%,当药物浓度为4.40μg.ml-1时抑制率为30.23%。结论藤茶总黄酮对体外SGC-7901细胞的生长有明显的抑制作用。

基于熵权法和灰色关联分析的藤茶理化品质评价与分级应用

以收集的10种藤茶样品为对象,测定15项藤茶相关理化品质指标,并通过变异分析、相关性分析与主成分分析确定茶汤的黄酮(A11)、多酚(A12)、可溶性糖(A13)及亮度(A3)4项核心品质指标;在采用熵权法确定品质指标权重后,结合灰色关联度分析法,构建出藤茶理化品质评价模型为:φi=ξA11×0.181 1+ξA12×0.224 2+ξA13×0.415 4+ξA3×0.179 3,且模型得分与感官评分拟合度达0.822;根据模型得分运用聚类分析将藤茶样品分成3个级别。

广西瑶族藤茶化学成份的研究

从广西瑶族藤茶,即显齿蛇葡萄(Ampelopsis grossedentata)中提取分离出两种黄酮类化合物,经化学和光谱解析,鉴定为杨梅树皮素(Myricetin,C_(15)H_(10)O_8,结晶Ⅰ),双氢杨梅树皮素(DL-dihydromyricetin,C_(15)H_(12)O_8,结晶Ⅱ),其中杨梅树皮素为首次报道从该植物中获得。