Epicatechin attenuates lead(Pb)-induced cognitive impairment in mice:regulation on Nrf2 signaling pathway,and interference on the interaction between Pb with albumin

Epicatechin(EC)was used in this study to antagonize the cognitive dysfunction caused by lead(Pb)exposure in mice.Eight-week-old male Kunming mice were treated with PbCl_(2)(20 mg/kg)and/or EC(50 mg/kg)by gavage administration for 4 weeks.Morris water maze test showed that EC could improve memory dysfunction induced by Pb.EC antagonized Ca^(2+)overload,activated Nrf2 signaling pathway and reduced the accumulation of Pb in the brain and serum,which suggested that EC might alter Pb distribution in mice.In vitro,spectroscopic analysis,potentiometric titration and docking studies were applied to inquiry into the interaction between bovine serum albumin(BSA)and Pb^(2+)in presence or absence of EC.EC was proved to chelate Pb^(2+)and reduced the interaction between BSA and Pb^(2+).In summary,EC might protect Pb-induced cognitive impairment by activating Nrf2 signaling pathway,and suppressing Pb accumulation via interference on the binding of Pb to albumin.

Catechin and Epicatechin. What’s the More Reactive?

Catechin and epicatechin are two isomeric flavonoids. Despite the vital properties highlighted by numerous scientific studies, very little data is available on the intrinsic reactivity of these compounds. To provide more details on the stability and reactivity of catechin and epicatechin, this study is performed by means of theoretical calculation methods. For this purpose, geometry optimizations and frequency calculations at the B3LYP/6-31 + G (d, p) level of theory has been carried out and Natural Bond Orbital (NBO) analysis and VEDA (Vibrational Energy Distribution Analysis). The geometric and energy parameters and NBO analysis show that catechin appears more stable than epicatechin. The hydroxyl group position on the ring C of the catechol structure represents a factor that influences this relative stability. The global and local reactivity parameters reveal that epicatechin becomes more reactive than catechin. They indicate that their hydroxyl groups correspond to their most receptive sites. Fukui indices, VEDA and acidity study establish that O28–H29 remains the most reactive.

RNA-seq analysis of protective effect of epicatechin gallate on H_(2)O_(2)-induced oxidative injury in PC12 cells

Epicatechin gallate(ECG)is one of the polyphenolic compounds and has attracted much attention due to its various bioactivities.In this study,the neuroprotective eff ect of ECG against H_(2)O_(2)-induced oxidative injury in PC12 cells as well as the possible mechanisms were investigated.Cell viability was determined by MTT assay.The differentially expressed genes(DEGs),GO enrichment,and KEGG enrichment were analyzed to explore the mechanism of ECG against H_(2)O_(2)-induced oxidative injury by using the RNA-seq method.Finally,the change in the cell cycle was analyzed by fl ow cytometry.H_(2)O_(2)(400-1200μmol/L)inhibited the cell viability in a concentration-dependent manner.ECG(6-150μmol/L)eff ectively attenuated the H_(2)O_(2)-induced decrease in cell viability.RNA-seq analysis showed that ECG regulated 1058 coexpressed DEGs.GO enrichment analysis showed that the cellular component was the dominant group after ECG treatment.KEGG analysis showed that the cell cycle,fanconi anemia pathway,and homologous recombination were the important pathways for ECG in improving H_(2)O_(2)-induced oxidative injury and 28 coexpressed DEGs in the cell cycle pathway were summarized.Finally,cell cycle analysis also proved that ECG improved H_(2)O_(2)-induced cell cycle arrest in the G2/M phase.Our present study demonstrated that ECG attenuated H_(2)O_(2)-induced neurologic oxidative damage by multiple modulatory mechanisms at the molecular transcription level.These fi ndings provide new insights for further study of the molecular mechanism of the neuroprotection of ECG.

Altered Redox Status in Erythrocytes From Hypertensive Subjects: Effect of(-)Epicatechin

Hypertension is a major problem worldwide. There is much evidence to suggest that reactive oxygen species (ROS) radical may play a role in the development of organ damage associated with cardiovascular disease and hypertension. (-)Epicatechin, a member of tea catechins belonging to flavonoid group, is known to be a potent anti-oxidant. The study has been undertaken to evaluate the effect of (-)epicatechin on markers of oxidative stress: reduced glutathione (GSH) and membrane sulfhydryl (-SH) groups in erythrocytes from hypertensive patients. The effect of (-)epicatechin was also compared with a known anti-oxidant L-ascorbic acid. The erythrocyte intracellular GSH content and membrane -SH group content were significantly (P<0.01) decreased in hypertensive subjects. In vitro incubation with (-)epicatechin caused an increase in GSH and -SH content, the effect was more pronounced in hypertensive erythrocytes. Similar results were obtained with L-ascorbic acid. The observed decrease in the level of GSH and -SH groups in hypertension is an indicator of oxidative stress condition. Observation of an increase in red cell GSH content and the protection of membrane -SH group oxidation by (-)epicatechin in hypertensive subjects is a convincing reason to suggest that high dietary intake of foods rich in catechins may help to reduce oxidative stress and concomitant free radical damage in hypertensive patients.

Optimization of Extraction Process of Fagopyri Dibotryis Rhizoma by Orthogonal Experiment

[Objectives]To optimize the water extraction process of Fagopyri Dibotryis Rhizoma.[Methods]The entropy weight method was used to determine the weight of epicatechin extraction rate and dry extract rate and calculate the comprehensive score.The water extraction process of Fagopyri Dibotryis Rhizoma was optimized by orthogonal design with the comprehensive score as the indicator and the amount of water,extraction time and extraction times as the factors.[Results]The optimum extraction process of Fagopyri Dibotryis Rhizoma was as follows:adding 10 times of water,extracting 3 times,and extracting for 60 min each time.[Conclusions]The optimized extraction process is stable and feasible,and can be used for the extraction of Fagopyri Dibotryis Rhizoma.

金荞麦胶囊中间体制备工艺的优选及质量控制

目的:优选金荞麦胶囊中间体的制备工艺以及质量控制。方法:以表儿茶素为实验指标,通过正交实验,围绕提取时间、回流时间、回流次数考察选取最佳工艺。结果:当溶剂为药材的6倍量,乙醇浓度为50%,回流为1 h为最佳制备工艺。结论:所建立的方法操作容易,结果准确可靠重现,可显著提高表儿茶素的提取,可用于金荞麦胶囊中间体的制备。

表儿茶素的碳酰化改性及其紫外吸收和抗氧化活性

为增强表儿茶素衍生物的紫外吸收性能、改善其在油脂等非极性溶剂中的溶解度,以甲烷磺酸为溶剂和催化剂,由表儿茶素和对羟基苯甲酸合成了2,2'-二(对羟基苯甲酮基)-表儿茶素,经柱层析分离得到目标产物,采用高效液相色谱(HPLC)验证纯度,运用紫外-可见光(UV-vis)光谱、傅里叶变换红外(FT-IR)光谱、液相色谱-质谱联用(LC-MS)和核磁共振(NMR)波谱等表征手段确证目标产物结构。评价了2,2'-二(对羟基苯甲酮基)-表儿茶素的紫外吸收性能,以及对2,2-联氮-二(3-乙基苯并噻唑-6-磺酸)二铵盐阳离子自由基、1,1-二苯基-2-三硝基苯肼自由基和超氧阴离子自由基清除能力。结果表明,合成的2,2'-二(对羟基苯甲酮基)-表儿茶素与常用紫外线吸收剂4-甲氧基肉桂酸-2-乙基己酯(OMC)具有相似的紫外吸收范围和相当的摩尔吸光系数,有望成为一种性能优良的UVB波段紫外线吸收剂;2,2'-二(对羟基苯甲酮基)-表儿茶素具有良好的体外抗氧化活性,其体外抗氧化能力高于维生素C(VC)、略低于表儿茶素,有望应用于化妆品领域。

(-)-表儿茶素通过调控A549R细胞自噬改善放疗敏感性的作用机制

目的 探讨(-)-表儿茶素[(-)-Epicatechin, EC]通过联合放疗(Radiotherapy, RT)改善非小细胞肺癌细胞放疗敏感性的作用机制。方法 体外培养A549人非小细胞肺癌细胞,构建放疗抵抗株A549R。通过细胞计数试剂盒8(Cell Counting Kit-8,CCK-8)检测细胞增殖活力,脱氧核苷酸末端转移酶介导的dUTP缺口末端标记(terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, TUNEL)染色观察细胞凋亡情况,Transwell实验检测细胞迁移能力。蛋白质免疫印迹(Western blot)检测凋亡相关蛋白(Bcl-2、Bax、Cleaved Caspase-3)和自噬相关蛋白(Beclin、LC3II/I)的表达。免疫荧光染色检测Cleaved Caspase-3和LC3的表达。单丹磺酰尸胺(Monodansylcadaverine, MDC)染色检测自噬体的形成。结果 EC联合RT抑制细胞增殖和迁移能力、诱导细胞凋亡和自噬、下调Bcl-2的表达、上调Bax、Cleaved Caspase-3、Beclin和LC3Ⅱ/I的表达,而加入自噬抑制剂(Chloroquine, CQ)或mTOR信号通路激活剂MHY1485处理后部分减弱了EC联合RT处理对细胞的作用。结论 EC可作为放疗增敏剂,通过抑制mTOR信号通路诱导A549R细胞自噬和凋亡改善放疗敏感性。

Interaction of epicatechin with bovine serum albumin using fluorescence quenching combined with chemometrics

The interaction between BSA and epicatechin was studied using fluorescence quenching titrations combined with trilinear decomposition method and excitation-emission matrix(EEM)fluorescence.The resolved spectra were highly similar with the actual ones which indicated that the resolved results were reliable.The relevant parameters of the binding process were obtained by quantifying each substance in the complicated mixtures in situ.The quenching was static quenching,epicatechin had a weak interaction with BSA and the binding site was one.The total concentration and the free concentration of quenchers had different effect on the system.The results demonstrated that the method exploited in this article is a useful tool to investigate complicated interactions,avoiding complicated pretreatment and simplify experimental procedure.

表儿茶素没食子酸酯与菊粉复配对鲈鱼肌球蛋白的影响

以鲈鱼肌球蛋白为研究对象,通过分析浊度、粒径、电位、溶解度、活性巯基、二聚酪氨酸含量等,探究不同质量分数(0.1%,0.2%,0.3%,0.4%)的表儿茶素没食子酸酯复配多糖(1%的菊粉)对鲈鱼肌球蛋白特性的影响。结果表明,随着表儿茶素没食子酸酯质量分数的增加,浊度与粒径呈先下降后上升的趋势,电位、溶解度、活性巯基含量呈先上升后降低的趋势,而二聚酪氨酸的变化趋势则与之相反。添加0.2%表儿茶素没食子酸酯与1%菊粉的鲈鱼肌球蛋白,浊度与粒径最小,粒径降低到279 nm;电位绝对值、溶解度以及活性巯基值最大,电位绝对值以及活性巯基分别为6.37 mV,24.34 nmol/mg prot;二聚酪氨酸含量最低。因此,不同质量分数的表儿茶素没食子酸酯与1%的菊粉协同作用可改善鲈鱼肌球蛋白的理化性质,研究结果为多酚协同多糖改善鱼糜凝胶特性提供了理论依据。二聚酪氨酸的含量表明,多酚协同多糖还可以增加肌球蛋白的抗氧化性。

基于网络药理学和分子对接法分析5种中药活性成分治疗心肌缺血再灌注损伤的机制

目的利用网络药理学和分子对接法的分析技术,预测大黄素、木香烃内酯、水甘草碱、表儿茶素没食子酸酯、冬凌草甲素等中药活性成分治疗心肌缺血再灌注损伤的作用机制。方法使用中药系统药理数据库和分析平台(Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform,TCMSP)、HERB和SwissTargetPrediction数据库寻找5种药物活性成分的作用靶点,并通过Genecards数据库寻找心肌缺血再灌注损伤的疾病靶点,两组靶点相交得到5种活性成分针对于心肌缺血再灌注损伤的潜在治疗靶点组合。接着对上述靶点合集进行功能富集(采用R语言程序,“ClusterProfiler”包),并进一步分析,随后构建活性成分、靶点、通路、疾病和富集结果间的多种关系网络,使用Cytoscape进行美化。使用String数据库和Cytoscape软件构建靶点蛋白互作网络(protein-protein interaction networks,PPI)集合,并利用Cytoscape的CytoHubba功能筛选关键(hub)靶基因。使用PyMOL和Autodock软件进行分子对接和结果可视化及美化。结果5种活性成分治疗心肌缺血再灌注损伤的潜在作用靶点共有51个,我们发现在整体的蛋白互作网络中排名前5位的关键基因分别为编码丝氨酸/苏氨酸蛋白激酶1(Akt serine/threonine kinase 1,AKT1)、白细胞介素1β(interleukin-1β,IL-1β)、半胱天冬酶3(Caspase 3,CASP3)、血管内皮生长因子A(vascular endothelial growth factor A,VEGFA)、信号转导子和转录激活子3(signal transolucer and activator of transcription 3,STAT3),它们涉及基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)相关富集通路74条、基因本体论(gene ontology,GO)生物过程富集条目1007条、GO细胞功能富集条目39条。随后的分子对接结果发现,这5种活性成分各自与关键基因中的一种或多种结合较好。结论大黄素、木香烃内酯、水甘草碱、表儿茶素没食子酸酯、冬凌草甲素5种中草药药物活性成分可能主要通过AKT1、IL-1β、CASP3、VEGFA、STAT3等靶点作用于多种通路来发挥治疗心肌缺血再灌注损伤的作用。

高效液相色谱及红外光谱法分析鸡血藤提取物中儿茶素类成分

建立高效液相色谱结合红外光谱法检测鸡血藤提取物中儿茶素类成分原儿茶酸、儿茶素、表儿茶素。利用Design-Expert13.0.6设计响应面试验,优化甲醇体积分数、液料比、超声时间、超声温度交互的提取条件,确定最高提取率。采用高效液相色谱(HPLC)法与红外光谱法对鸡血藤提取物中儿茶素类成分进行定量和定性分析,确定儿茶素类成分含量和单体结构。样品经甲醇溶液超声提取,以0.2%(质量分数)H3PO4-乙腈作为流动相进行梯度洗脱,采用InertsilTM ODS-35μm色谱柱(150 mm×4.6 mm,5μm)进行分离,柱温为30℃,流量为1 mL/min,检测波长为260 nm,进样体积为10μL。红外光谱法采用KBr压片法测定成分含量。原儿茶酸、儿茶素、表儿茶素的质量浓度在100~1000μg/mL范围内与色谱峰面积线性关系良好,相关系数分别为0.9997、0.9992、0.9993。利用Design-Expert13.0.6确定超声波最优提取工艺为超声时间40 min,超声温度51℃,甲醇体积分数50%,液料比50∶1 mL/g,得到儿茶素类物质总质量分数为7.8837 mg/g。红外光谱法证明鸡血藤中具有儿茶素类物质的单体或聚合体成分,为鸡血藤中儿茶素类物质的开发和质量控制提供光谱学理论基础和依据。

正交试验优选金荞麦提取工艺

目的:优选金荞麦水提取工艺。方法:采用熵权法确定表儿茶素提取率和干膏率的权重并计算综合得分,以综合得分为指标,采用正交试验设计,以加水量、提取时间、提取次数为考察因素,优化金荞麦水提取工艺。结果:金荞麦最佳提取工艺为加10倍量水,提取3次,每次提取60 min。结论:优选出的提取工艺稳定可行,可用于金荞麦的提取。

(-)-表儿茶素和植物铁蛋白的非共价结合及功能表征

采用荧光光谱、圆二色谱、透射电镜、动态光散射等手段研究去铁红小豆铁蛋白(apoRBF)与表儿茶素(EC)的非共价络合及其对蛋白质结构和功能性质的影响。荧光结果表明,EC未改变apoRBF的特征发射峰330 nm,且随浓度的升高,apoRBF荧光强度下降,EC与apoRBF发生相互作用,引起蛋白质三级/四级结构的改变,而对蛋白质的一、二级结构没有影响。荧光拟合显示二者的结合常数K和结合位点数n分别为3.65×10^(4)mol/L^(-1)和98.5。铁蛋白-表儿茶素复合物(FEC)在4℃和40℃下透析12 h,EC的释放率分别为29.1%和45.9%,均低于游离EC的释放率,表明EC与apoRBF发生结合,且低温更有利于二者的结合。经模拟胃肠液孵育2 h后,FEC中EC的释放率分别为68.6%和32.2%,与游离EC的释放率相比,表现出相对较慢和持续的释放过程,表明EC与apoRBF的结合显著抑制模拟胃肠液中蛋白酶对铁蛋白的降解,促进功能组分的缓释作用。此外,FEC保留了表儿茶素的抗氧化能力但略有下降。本研究结果明确了多酚与植物铁蛋白作用机理,为表儿茶素与植物铁蛋白非共价复合物的应用提供理论参考。

高效液相色谱法同时测定茶叶中表儿茶素及其氧化二聚体、没食子酸和咖啡碱的含量

目的:本研究旨在建立同时分析茶叶中4种表儿茶素(表儿茶素、表儿茶素没食子酸酯、表没食子儿茶素和表没食子儿茶素没食子酸酯)及其氧化二聚体(4种茶黄素(Theaflavins,TFs):茶黄素、茶黄素双没食子酸酯、茶黄素-3-没食子酸酯和茶黄素-3’-没食子酸酯)、3种聚酯型儿茶素(Theasinensins,TSs)(TSA、TSB和TSC)、没食子酸和咖啡碱的高效液相色谱(High performance liquid chromatography,HPLC)方法。方法:首先利用化学合成的方法制备TSA、TSB和TSC;然后参照文献对HPLC流动相做适当调整和对梯度洗脱条件进行优化,色谱柱为Cosmosil 5C18-AR-Ⅱ色谱柱(250 mm×4.6 mm,5 m),流动相为纯水(A)、50 mmol/L磷酸(B)和乙腈(C),检测波长为280 nm,流速为0.8 mL/min,柱温为30℃,进样量为20 L;最后根据建立的HPLC方法对绿茶、乌龙茶、红茶和黑茶中的上述13种物质含量进行测定。结果:在最优梯度洗脱条件下4种表儿茶素、4种TFs、3种TSs、没食子酸及咖啡碱可在66 min内得到较好地分离,同时各物质在0.01~1.00 mg/mL的质量浓度范围内与其峰面积的线性关系良好(R2均在0.9904~0.9966范围内),重复性相对标准偏差(The relative standard of deviation,RSD)为1.034%~4.008%,精密度RSD为1.882%~4.835%,稳定性RSD为0.349%~3.994%,三种浓度的加标回收率在90.106%~107.331%之间且RSD<3.268%。此外,上述13种物质含量在不同茶叶样本间存在显著差异,且所有检测值均在标准曲线有效测定范围内。结论:本方法操作简单高效、结果准确可靠,可用于茶叶中表儿茶素、茶黄素、聚酯型儿茶素、没食子酸和咖啡碱的同时分析。

植物黄酮在抗新冠病大流行中的作用:人们对绿茶黄酮的使用

2020年笔者报道了植物黃烷3醇没食子酸酯(flavan-3-ol gallates,F3G)、二聚原花青素和富含这些化合物的绿茶在体外具有抑制新冠病毒(SARS-CoV-2)的主蛋白酶(main protease)活性.最近,笔者报道了F3G和其他黄酮化合物能抑制人类冠状病毒229E在细胞中繁殖.此外,许多研究也报道绿茶和植物黄酮对新冠病治疗的益处.自2020年12月以来,在美国和土耳其,笔者采用人口统计学和民族药学方法研究了新冠感染者利用绿茶帮助康复的情况.在美国,笔者统计了居家隔离的23名感染者用茶来康复的数据.其中5位感染者授权笔者分享他们用绿茶帮助康复的经验.在土耳其,笔者统计了100位不同年龄(20个月至96岁)和性别的新冠感染者恢复的详细资料,他们在没得到任何医疗帮助的情况下从新冠病中康复.在隔离期间,除了饮食,只饮用绿茶.根据他们每天的喝茶量和康复所用时间,完成了皮尔逊积矩相关系数的分析.结果表明,每天喝绿茶量和康复时间成负相关,喝绿茶越多,康复时间越短.同时,2020年笔者收集了208个国家人均喝茶量数据:土耳其人均喝茶量最多(3 kg);很多拉美国家如墨西哥,人们不喝茶.2021年收集了100个国家的人均喝茶量数据:土耳其人均喝茶量最多(3.4 kg);很多国家如墨西哥,人们不喝茶.同样,笔者收集了2020和2021年各国的新冠感染数和死亡数,计算出每个国家每年的平均死亡率,以及2年的平均死亡率.结果发现:到2020年11月30日和2021年12月31日止,土耳其的年均死亡率大约是0.96%和0.95%,而墨西哥的年均死亡率大约是10.56%和9.81%;截至2021年12月31日,土耳其的2年平均死亡率大约是0.87%,而墨西哥2年平均死亡率大约是7.54%.根据2020年的115和121个国家、2021年的93个国家的平均喝茶量和平均死亡率,笔者进行了皮尔逊积矩相关系数的分析,结果表明,人均喝茶量和死亡率成负相关,喝茶越多,死亡率越小.这些数据提示,喝茶特别是喝绿茶有助新冠病人的康复.另外,在这篇报道里,笔者介绍了如何用涩和苦味来辨别绿茶里是否有F3G、二聚原花青素和槲皮素,笔者还提醒在茶里不能加任何奶制品.当然,笔者也强调绿茶中的F3G、二聚原花青素、槲皮素和其他植物黄酮对新冠病的治疗有效性,还有待进一步研究.

‘上海双棱扁’大麦种子紫色色素以及脂质组分的研究

以“紫籽”(purple-seeded,“PS”)以及“黄籽”(yellow-seeded,“YS”)大麦为研究材料,利用液相色谱-质谱联用仪(liquid chromatograph mass spectrometer,LC-MS)系统分析大麦籽粒表儿茶素(epicatechin,EC)含量。结果表明:“紫籽”大麦籽粒表儿茶素(epicatechin,EC)含量显著高于“黄籽”大麦。通过同源比对获得‘SLB’中Hv TTG1(TRANSPARENT TESTA GLABRA1)全长基因,在拟南芥中超表达Hv TTG1后,转基因拟南芥叶片颜色呈现紫色。脂质组学分析显示,“紫籽”中多种脂质组分含量均高于“黄籽”,包括1种单酰甘油(monoacylglyceride,MG)、12种二酰甘油(diacylglyceride,DG)、67种三酰甘油(triacylglyceride,TG)以及具有高营养价值的亚油酸(C18∶2)与亚麻酸(C18∶3)。综上,初步认为Hv TTG1在大麦种子紫色种皮形成中起到潜在的调控作用,并且‘紫籽’大麦相对‘黄籽’大麦,籽粒含有更高的亚油酸以及亚麻酸。研究可对紫色大麦在新食谱中的应用提供一定的参考依据。

丽江山荆子表儿茶素抗辣木叶蛋白过敏作用

为探讨丽江山荆子表儿茶素(Epicatechin,EC)抗辣木叶粗蛋白(Moringa oleifera leaf protein,MOpA)诱导的过敏作用,利用小鼠进行食物过敏反应试验,观察小鼠的过敏症状,测定其体质量、胸腺指数和脾脏指数;检测小鼠血清中组胺(Histamine,HIS)、白细胞介素-4(Interleukin,IL-4)、肿瘤坏死因子-α(Tumor Necrosis Factor-Alpha,TNF-α)质量浓度。苏木精-伊红染色法(Hematoxylin-Eosin Staining,HE)观察小鼠空肠组织病理变化的影响。结果发现,用MOpA激发后,MC组小鼠脾脏指数显著高于NC组(P<0.01),胸腺指数相较于EC组差异明显(P<0.05);EC组相较于MC组小鼠血清中的HIS含量降低了3.99×10^(3)ng/L(P<0.01),TNF-α含量升高了97.33×10^(3)pg/L(P<0.01),IL-4含量降低了6.22×10^(3)pg/L(P<0.05);HE染色发现,MC组出现肠绒毛断裂及萎缩现象;EC组病理现象不明显。EC能够通过保护肠道黏膜屏障和在一定程度上抑制炎症来改善MOpA诱导的过敏小鼠的症状。该研究表明MOpA和卵清蛋白、牛乳蛋白和花生蛋白等过敏原一样具有潜在的致敏性;EC可能是一种有效的食物来源的免疫调节剂,用于治疗食物过敏。

基于现行标准的葡萄籽提取物工艺优化研究

目的:为确保葡萄籽提取物(GSE)的安全性和有效性,基于中医药保健品进出口商会和美国药典USP43标准,对GSE的提取工艺进行优化。方法:以原花青素值、儿茶素与表儿茶素含量和作为关键质量属性(CQAs),首先优选提取溶剂,并在单因素实验基础上,通过质量源于设计(QbD)理念建立了葡萄籽提取物的设计空间与优化空间。结果:单因素实验提示,丙酮对原花青素的提取效率最高,且儿茶素、表儿茶素在提取物中的含量显著低于乙醇、甲醇等提取溶剂;方差分析结果表明,通过Box-Behnken设计建立的提取工艺模型具备统计学意义(P<0.0001),葡萄籽提取物的优化提取工艺为丙酮体积分数40%~48%,料液比1∶10 g/mL,提取时间1.5 h,提取1~3次,以优化工艺参数提取,提取物中原花青素值为1.8079%~1.9643%,儿茶素和表儿茶素的含量和不高于0.8131%(RSD<5%),此优化工艺可为GSE的工业化生产提供参考。

基于多指标综合评分法优选茅莓根水提工艺

目的:优选茅莓根的水提工艺。方法:建立茅莓根水提液中表儿茶素含量的高效液相色谱法(high performance liquid chromatography,HPLC)测定方法,采用正交设计法,以干膏得率和表儿茶素含量的综合评分为评价指标,考察浸泡时间、加水量、煎煮次数及煎煮时间4个影响因素对茅莓根水提工艺的影响,确定最佳的水提工艺并进行工艺验证。结果:表儿茶素浓度在15.044~300.88μg/mL内线性关系良好(r2=0.9998),平均回收率为101.7%,RSD为2.57%;茅莓根的最佳水提工艺为加10倍量水,浸泡0.5 h,煎煮3次,每次0.5 h;3份茅莓根饮片水提工艺验证试验的综合评分分别为0.78、0.76、0.77分,干膏得率和表儿茶素含量的RSD均小于2%(n=3)。结论:建立的表儿茶素含量测定方法准确、稳定、重复性好,优选的茅莓根水提工艺稳定可行,可为茅莓根的制剂研究与质量控制提供参考。