Anti-Hypertensive Effects of Blended <i>Camellia oleifera</i>Abel Oil and Eucommia Extract on SHR Mice

In our study, we employed Camellia seed oil as the main ingredients blended with Eucommia Extract to investigate the effects of anti-hypertensive on mice by administrating mice with low dose, middle dose and high dose of Camellia seed oil complex for 4 weeks. The specific tests of studying effects of anti-hypertensive were body weight, blood systolic pressure (BSP), diastolic blood pressure (DBP), pm meam blood pressure (MBP) and heart rate (HR). And the results showed that appropriate level of Camellia seed oil complex could decrease the body weight and had an active effect on the cardiovascular system of mice, which significantly embodied the anti-hypertensive activity of Camellia seed oil complex.

Comprehensive Assessment of the Safety of Eucommia ulmoides Leaf Extract for Consumption as a Traditional Chinese Health Food

To ensure the export quality of Eucommia ulmoides leaf extract(ELE)and facilitate E.ulmoides leaf inclusion in the directory of traditional Chinese health foods,an overall safety assessment of ELE was performed,including genotoxicity and long-term toxicity,according to the national food safety standards of China.No variations in the reverse mutation number of the nominal bacterial strains were observed under ELE treatment in comparison with the solvent control.Additionally,the micronucleus rates of in vivo mammalian erythrocytes and in vitro mammalian cells under ELE treatment were equivalent to or significantly lower than those of the solvent control.The fold change in the trifluorothymidine resistance mutation frequency of the thymidine kinase gene under ELE treatment was less than three times in comparison with the solvent control,suggesting that ELE did not cause genotoxicity.Moreover,animal experiments showed that the growth performance of rats under ELE treatment was enhanced because the body weights of rats increased.No oxidative injury or inflammatory responses were induced and no histopathological lesions of tissues were detected under ELE treatment.In addition,plasma triglycerides and low-density lipoprotein cholesterol levels significantly decreased,and plasma high-density lipoprotein cholesterol levels significantly increased with ELE treatment,suggesting that ELE was health-promoting.Furthermore,moderate to excellent antimicrobial activities,a favorable anticancer capacity,and superior antioxidant abilities of ELE were found,implying ELE possesses good bioactivities.Therefore,we affirmed ELE is safe to consume as a traditional Chinese health food.

杜仲提取物对母猪繁殖性能、泌乳性能和仔猪生长性能的影响

文章旨在分析不同水平杜仲提取物对妊娠母猪繁殖性能、泌乳性能及后代仔猪生长性能的影响。试验选择体况、日龄、体重、胎次(1胎)及预产期等相近的妊娠90 d的“长×大”二元母猪60只作为试验动物,随机分成4组,每组15个重复,每头妊娠90 d的“长×大”二元母猪为1个重复组,组别分别在基础日粮中添加0(1组)、1.0%(2组)、2.0%(3组)、3.0%(4组)杜仲提取物,从试验用妊娠母猪90 d开始饲喂至哺乳期21 d试验结束,试验为期46 d。结果表明:(1)与试验1组相比,试验3、4组母猪的产活仔数、初生活仔猪均重显著提高13.2%、13.3%、8.3%、9.1%(P<0.05);(2)与试验1组相比,试验3、4组母猪乳汁的乳脂率、乳糖率显著提高7.6%、7.9%、11.0%、11.2%(P<0.05),其背膘厚度损失显著降低7.2%、8.1%(P<0.05);(3)与试验1组相比,试验3、4组断奶仔猪均重、平均日增重显著提高8.3%、8.8%、13.9%、16.7%(P<0.05),其断奶仔猪腹泻率显著降低39.4%、39.6%(P<0.05)。综上所述,不同水平杜仲提取物可提高妊娠母猪繁殖性能、泌乳性能及后代仔猪生长性能,综合使用成本以基础日粮中添加2.0%杜仲提取物效果较好,可以在生产中推广应用。

杜仲叶多糖的提取、结构及抗氧化活性研究

【目的】探究微波辅助提取杜仲叶多糖的最佳条件,分析杜仲叶多糖的结构组成及抗氧化活性,为杜仲叶综合利用提供依据。【方法】采用微波辅助提取法,以杜仲叶多糖得率为指标,m(杜仲叶粉/g)∶V(H_(2)O/mL)(以下简称质量体积比)、微波时间、水浴温度、微波功率为影响因素设计单因素试验,在此基础上采用正交试验优化得到杜仲叶多糖最佳提取条件。根据该条件提取6个品种杜仲叶(华仲1号、华仲5号、华仲12号、华仲13号、华仲15号、华仲24号)多糖,使用气相色谱-质谱联用仪及红外光谱仪测定杜仲叶多糖结构组成,并通过电子顺磁共振波谱法测定杜仲叶多糖1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl radical,DPPH)自由基清除率表征其抗氧化活性。【结果】杜仲叶多糖的最佳提取条件是质量体积比1∶30,微波时间1.5 min,水浴温度40℃,微波功率230 W。在该条件下6个品种杜仲叶得率分别为华仲1号6.90%±0.04%、华仲5号6.47%±0.13%、华仲12号6.68%±0.11%、华仲13号6.53%±0.07%、华仲15号7.21%±0.02%和华仲24号7.64%±0.05%。在结构组成方面,单糖组成结果显示,6个品种杜仲叶多糖均由L-鼠李糖、D-阿拉伯糖、D-木糖、D-甘露糖、D-葡萄糖和D-半乳糖组成,其中D-葡萄糖和D-半乳糖含量最高,但其单糖组成比例存在差异;多糖红外光谱显示,不同杜仲叶多糖具有相似的多糖特征吸收峰。在抗氧化活性方面,6个品种杜仲叶多糖DPPH自由基清除能力顺序为华仲1号>华仲13号>华仲12号>华仲24号>华仲5号>华仲15号。【结论】微波辅助提取可以提高杜仲叶多糖得率,不同杜仲叶多糖均有良好的抗氧化活性,且以华仲1号的DPPH自由基清除能力最强。

杜仲叶水提取物对植物乳杆菌体外益生特性影响

为明确杜仲叶水提取物对植物乳杆菌体外益生特性的影响,采用活菌计数、扫描电镜和气相色谱等方法探究不同浓度ELWE对植物乳杆菌生长曲线、产酸性能、形态和耐受性等的影响。结果表明,培养24 h后,试验组的活菌数均显著高于对照组;ELWE(80,320 mg/mL)使植物乳杆菌菌体更加饱满,且能显著提高其产乳酸能力,36 h时乳酸含量分别提高42.07%和111.64%。在胃液环境的胁迫下,80 mg/mL ELWE组的对数存活率达到87.77%(3 h),显著高于对照组(0%);80 mg/mL ELWE可显著提高植物乳杆菌在热、NaCl、胆盐和真空冷冻干燥胁迫环境下的活菌数,分别保持在5.67,8.16,7.65,7.78 lg CFU/mL。80 mg/mL ELWE对植物乳杆菌体外益生特性有积极影响。研究为ELWE在益生菌行业的应用提供理论参考。

荷叶山楂杜仲叶复配提取物对大鼠脂质代谢的协同调控作用

通过与单一植物提取物相比,探究荷叶、山楂、杜仲叶复配提取物协同血脂调节作用及其机制。采用超临界萃取技术得到荷叶、山楂、杜仲叶以及复配提取物,对高脂饲养的Wistar大鼠进行灌胃,并进行肝脏形态学观察和脂质代谢基因表达水平检测。结果表明,与单一提取物组和高脂模型组相比,复配提取物显著降低大鼠体质量(P<0.05),同时显著改善大鼠血脂代谢(P<0.05)。肝脏苏木精-伊红染色结果显示复配干预组肝组织中脂滴空泡显著减少,与高脂模型组和单一提取物组相比,复配干预组大鼠肝脏组织中细胞形态具有更明显改善。分子检测结果显示,与单一提取物相比,复配提取物能够显著提高大鼠肝脏PPARα和CYP7A1表达水平(P<0.05),降低小肠中NPC1L1表达水平(P<0.05)和显著升高ABCG5表达水平(P<0.05)。综上所述,荷叶、山楂、杜仲叶复配提取物可有效调控大鼠脂质代谢水平,其调节机制通过上调PPARα/CYP7A1基因表达,同时在小肠层面降低NPC1L1和升高ABCG5,达到降低血脂的作用,与单一提取物相比,复配具有显著协同调控功能。

杜仲橡胶颗粒的冷冻法提取及其形态性质研究

采用液氮研磨法分离提取杜仲叶片和翅果中的橡胶粒子,利用光学显微镜观察到橡胶颗粒存在于一种细长的丝状单细胞中。并利用MATLAB软件对叶片和翅果中的橡胶粒子进行测量,发现叶片中的橡胶粒子直径跨度较小为1.5~7.0μm;而翅果中的橡胶粒子直径范围为1.0~16.6μm,直径跨度较大且存在大直径的橡胶粒子。同时对翅果橡胶粒子的分离提取和保存条件进行探索,发现选用新鲜、失水较少的杜仲翅果,加入液氮研磨可较好地分离提取橡胶粒子,并将获得的橡胶粒子保存于漂洗液中对橡胶粒子损伤最小。

杜仲叶免疫调节机制的网络药理学分析及验证

基于网络药理学及小鼠免疫抑制模型方法探讨杜仲叶免疫调节的作用机制。该研究通过TCMSP数据库筛选出3个杜仲叶活性成分,Uniprot和Swiss Target数据库预测到306个相关联的靶基因,经与OMIM、GeneCards数据库对比,获得105个免疫失调与杜仲叶的交集基因,通过Cytoscape3.8.2软件构建“活性成分-基因”网络。利用STRING数据库进行蛋白质-蛋白质相互作用分析,构建蛋白质-蛋白质相互作用网络(PPI),CytoNCA进行网络拓扑学分析,筛选出21个核心靶点,并对核心靶点进行基因本体(GO)富集分析与KEGG通路分析。结果发现,杜仲叶中的山奈酚、槲皮素、绿原酸等主要化合物通过调节肿瘤坏死因子(TNF)、白细胞介素6(IL-6)、血管内皮生长因子A (VEGFA)、白细胞介素1β(IL^(-1)β)等关键靶点,参与IL^(-1)7、肿瘤坏死因子信号通路等,从而发挥免疫调节作用。通过腹腔巨噬细胞体外试验和环磷酰胺免疫抑制体内试验探讨杜仲叶提取物的免疫调节作用,结果显示,1 000~5 000μg·mL^(-1)浓度的杜仲叶提取物可促进腹腔巨噬细胞增殖和吞噬能力;与模型组相比,杜仲叶提取物可增加小鼠免疫器官指数、吞噬指数、外周血白细胞和淋巴细胞数量,增强迟发型超敏反应(DTH)的耳廓肿胀。本研究展现了杜仲叶免疫调节多成分、多靶点作用的特点,为杜仲叶在畜禽健康养殖中的应用提供了科学依据。

杜仲水提物上调Nur77表达促进骨髓间充质干细胞增殖和成骨分化

背景:骨髓间充质干细胞作为成骨细胞的前体细胞,探索其分化机制对于预防和治疗骨质疏松症具有重大意义。杜仲能够诱导骨髓间充质干细胞成骨分化,但是杜仲对骨髓间充质干细胞增殖、分化以及Nur77/MDM2/p53通路的影响尚不明确。目的:探究杜仲水提物对骨髓间充质干细胞增殖和分化的影响并探讨其作用机制。方法:杜仲水提物处理人源和鼠源骨髓间充质干细胞,采用CCK-8法和Annexin V-FITC/PI法分别检测细胞增殖和凋亡情况,Western blot检测增殖、凋亡相关蛋白的表达,Nur77及其下游MDM2、p53相关蛋白的表达及泛素化前后的蛋白水平。成脂、成骨定向诱导分化后,Western blot检测脂肪细胞和成骨细胞的标志蛋白表达来评估其分化程度。转染Nur77 siRNA进入10 mg/mL杜仲水提物处理的骨髓间充质干细胞,检测细胞增殖、凋亡和分化情况。最后,敲低Nur77之后,使用p53抑制剂Pifithrin-α处理骨髓间充质干细胞,检测细胞增殖、凋亡和分化情况以明确其作用机制。结果与结论:①杜仲水提物可促进2种骨髓间充质干细胞的增殖和成骨分化,抑制凋亡和成脂分化;②杜仲水提物可上调Nur77、MDM2蛋白表达,促进p53蛋白泛素化;敲低Nur77基因则抑制MDM2蛋白表达及p53蛋白泛素化,促进p53蛋白表达,抑制2种骨髓间充质干细胞增殖和成骨分化;③p53抑制剂可逆转Nur77 siRNA的作用,促进2种骨髓间充质干细胞的增殖和成骨分化,抑制凋亡和成脂分化;④结果表明,杜仲水提物可以通过Nur77/MDM2/p53途径促进2种骨髓间充质干细胞的增殖和成骨分化,为杜仲在骨相关疾病方面的研究提供理论参考。

Antibacterial and Antioxidant Effects of Three Chlorogenic Acid Extracts

[Objectives] To study the antibacterial and antioxidant effects of chlorogenic acid extracts of Gynura procumbens,Lonicera japonica,and Eucommia ulmoides leaves,and provide a reference for their usage as natural food preservatives and antioxidants. [Methods]The disc diffusion method was applied to study the antibacterial activity of chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves against several common pathogens. In the antioxidant effects,study was carried out on the anti-lipid peroxidation,reducing capacity,and DPPH free radical scavenging capacity of chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves,respectively.[Results]Three chlorogenic acid extracts had strong inhibitory effects on bacteria,especially the inhibition on Staphylococcus aureus. At the concentration of 100 mg/m L,the bacteriostatic ring of chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves reached 21. 4,23. 6 and 24. 7 mm respectively. Besides,these chlorogenic acid extracts had significant inhibitory effect on Escherichia coli and Salmonella,but the inhibitory effect on the yeast was not obvious; the antibacterial intensity of antibacterial compounds was chlorogenic acid extracts of E. ulmoides > chlorogenic acid extracts of L. japonica > chlorogenic acid extracts of G. procumbens. Among these three chlorogenic acid extracts,the chlorogenic acid extracts of E. ulmoides had higher anti-lipid peroxidation,reducing capacity,and DPPH free radical scavenging capacity than other two chlorogenic acid extracts. [Conclusions] This paper reveals that among chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves,the chlorogenic acid extracts of E. ulmoides leaves have a stronger antibacterial activity and antioxidant activity.

杜仲提取物对蛋鸡生产性能、蛋品质和营养成分的影响

本研究旨在探究杜仲提取物对蛋鸡生产性能、蛋品质和营养成分的影响。试验将1200只200日龄产蛋率相近、健康状况良好的海兰褐蛋鸡随机分为4组,每组6个重复,每个重复50只。分别向基础饲料中添加0、100、200、400 g/t的杜仲提取物作为试验日粮。试验为期56 d,预饲期7 d,正试期49 d。日粮添加400 g/t的杜仲提取物可显著降低蛋鸡的软破蛋率和死亡率(P<0.05)、日粮中添加杜仲提取物对蛋鸡平均蛋重、平均日采食量、产蛋率和料蛋比均无显著影响(P>0.05)。日粮添加200和400 g/t的杜仲提取物显著提高蛋壳强度和哈氏单位(P<0.05);日粮中添加杜仲提取物对蛋白高度、蛋壳厚度、蛋黄颜色、哈氏单位、蛋形指数、蛋壳比例、蛋黄比例和蛋白比例无显著影响(P>0.05)。日粮添加杜仲提取物可显著提高鸡蛋粗蛋白质含量(P<0.05);显著降低鸡蛋总胆固醇和甘油三酯含量(P<0.05);对鸡蛋钙、磷、水分和卵磷脂含量无显著影响(P>0.05)。

HPLC法同时测定杜仲叶提取物中5种成分含量

建立同时测定杜仲叶提取物中5种成分含量的HPLC方法,色谱柱为岛津WondaCract ODS2 C18(4.6 mm×150 mm,5μm);流动相甲醇-0.4%磷酸水溶液,梯度洗脱,流速1 mL·min^(-1);柱温30℃;进样量10μL;京尼平苷酸、车叶草苷检测波长为238 nm,桃叶珊瑚苷、绿原酸、芦丁的检测波长分别为200、327、254 nm。结果表明,5种成分在检测范围内线性关系良好(R^(2)≥0.9999),平均加样回收率为98.4%~101.0%,RSD 1.06%~1.50%,10批杜仲叶提取物中5种成分含量的平均值分别为25.83、40.21、13.12、64.72、11.03 mg/g,本方法稳定可靠,重复性好,可对杜仲叶提取物样品中5种指标成分的含量进行同时测定。

杜仲叶提取物及发酵物对鸡骨发育的影响

为了研究日粮中添加杜仲叶提取物和杜仲叶发酵物对鸡骨发育的影响。试验取体重40 g左右、2日龄的雏鸡,随机分为对照组、杜仲叶提取物添加组、杜仲叶发酵物添加组3组,每组10只,试验期60 d。试验结束后剖杀,取胫骨进行CT检测、冰冻切片及染色,显微镜下观察形态结构的变化,用CT图像分析软件测定骨组织形态计量学参数。结果表明:杜仲叶提取物添加组和杜仲叶发酵物添加组与对照组的CT值相比显著升高(P<0.05),骨小梁面积占比显著升高(P<0.05);骨小梁间距极显著降低(P<0.05)。采用电感耦合等离子体质谱仪测定骨内微量元素发现,与对照组相比,2个试验组胫骨中的镁、钙、锌的含量均显著增高(P<0.05),杜仲叶发酵物添加组与对照组相比胫骨中的铜含量显著提高(P<0.05)。上述结果说明在鸡日粮中添加杜仲叶提取物和杜仲叶发酵物均可以改善鸡的骨发育和骨代谢,提高鸡骨内微量元素含量,使骨重建活动增加,一定程度上改善鸡的健康状况。

杜仲叶水提物和醇提物抑菌及其抗氧化活性研究

为比较杜仲叶水提物和醇提物抗菌及抗氧化活性,分别采用去离子水和乙醇(50%和75%)溶液提取杜仲叶,得到三种提取物,采用Alamar blue实验法测定提取物的抑菌效果,通过DPPH自由基、超氧阴离子及总还原力来评价其抗氧化活性。结果表明:三种杜仲叶提取物对细菌均有一定抑制活性,特别是对金黄色葡萄球菌的抑制活性最强,其中杜仲叶水提物、50%醇提物和75%醇提物对金黄色葡萄球菌MIC_(50)分别为7.21、3.32和4.12 mg/mL;但杜仲叶水提物对真菌黄曲霉无明显抑菌效果,杜仲醇提物抑菌效果强于杜仲水提物。三种杜仲提取物均具有较强的抗氧化活性,其中醇提物的清除DPPH、超氧阴离子能力及总还原力均高于水提物。总之,杜仲叶提取物均具有一定抗菌和抗氧化活性,具有作为食品防腐剂和抗氧化剂的潜力。

杜仲叶多糖的提取工艺优化及理化特性

为了研究杜仲叶多糖的最佳提取工艺,采取单因素实验结合响应面实验进行分析,比较液料比、提取时间、提取次数及醇沉处理的乙醇体积分数对杜仲叶粗多糖得率的影响.通过测定杜仲叶多糖中的化学组成、利用高效液相色谱仪测定相对分子质量、扫描电子显微镜观察表面形态、圆二色谱仪测定三股螺旋结构对杜仲叶多糖的结构进行初步分析,采用热重分析仪和差示扫描量热仪对杜仲叶多糖的热稳定性进行研究.结果表明:当提取温度为100℃时,杜仲叶粗多糖的最佳提取工艺条件为液料比(m L∶g)20∶1、提取时间3 h、提取次数3次、醇沉处理的乙醇体积分数60%,此时杜仲叶粗多糖的得率为(4.79±0.26)%.纯化后杜仲叶多糖的总糖含量为(89.12±0.92)%,蛋白质含量为(2.03±0.16)%,糖醛酸含量为(9.45±0.35)%,其结构为光滑、卷曲的网状结构,表明该多糖是一种不含有三股螺旋结构、纯度较高的酸性多糖.杜仲叶多糖在200℃以下的环境中具有良好的热稳定性.

杜仲叶乙醇提取物抑菌试验

以大肠杆菌、金黄色葡萄球菌、炭疽杆菌、枯草芽孢杆菌4种细菌和根霉、黑曲霉、青霉3种真菌为研究对象,通过打孔法和二倍稀释法探究了杜仲叶乙醇提取物在不同洗脱组分处理下,对上述细菌和真菌的抑菌效果和最大有效稀释倍数。结果表明:杜仲叶乙醇提取物乙酸乙酯部分、正丁醇部分各极性洗脱成分能够抑制大肠杆菌、金黄色葡萄球菌和炭疽杆菌生长,其中,对炭疽杆菌的抑制作用最好,最大抑菌圈直径可达到22.0 mm,但对枯草芽孢杆菌和3种真菌效果不明显。乙酸乙酯部分和正丁醇部分各极性洗脱成分的抑菌作用差别不大,对炭疽杆菌的最大有效稀释倍数可以达到32倍。

HPLC测定杜仲叶黄酮提取物中总黄酮含量方法优化

通过比较杜仲叶黄酮提取物经酸水解成苷元来折算总黄酮含量和直接测定未酸水解样品中黄酮总含量,优选出一种HPLC测定杜仲叶黄酮提取物中总黄酮方法。结果表明,酸水解测定比未酸水解测定总黄酮高。未水解法测定提取物中原生黄酮含量,而酸水解法将全部的黄酮苷水解成苷元后,测定苷元含量来换算的总黄酮含量更高,更具有代表性。所需的对照品种类更少,测定时间更短,因此,其检测成本更低,更适用于杜仲叶黄酮提取物中总黄酮的测定。

Dietary Eucommia ulmoides leaf extract improves laying performance by altering serum metabolic profiles and gut bacteria in aged laying hens

The leaves of Eucommia ulmoides are rich in bioactive constituents that have potential gastrointestinal benefits for animals.In aged laying hens,intestinal health issues contribute to a significant decline in egg-laying capacity during intermediate and later stages.It remains unclear whether E.ulmoides leaf extract(ELE)can improve intestinal health and enhance egg production in elderly laying hens,and the underlying mechanisms are yet to be elucidated.Therefore,we conducted a study with 480 laying hens(65 weeks old)randomly allocated into four groups:a control group fed with the basal diet,and three treatment groups supplemented with 500,1,000,and 2,000 mg/kg of ELE,respectively.The primary active constituents of ELE include flavonoids,polysaccharides,terpenoids,and phenolic acids.Dietary supplementation with ELE at 1,000 mg/kg(ELE1000)significantly improved laying performance and egg quality compared to the other groups.ELE1000 stimulated the maturation of intestinal epithelial cells,increased villus height,and reduced crypt depth.It also influenced the levels of proteins associated with tight junctions(claudin-1 and claudin-2)and intestinal inflammatory factors(IL-6,IL-1β,and IL-2)in different intestinal sections.Integrative analysis of serum metabolomics and gut microbiota revealed that ELE1000 improved nutrient metabolism by modulating amino acid and ubiquinone biosynthesis and influenced the abundance of intestinal microbiota by enriching pivotal genera such as Bacteroides and Rikenellaceae_RC9_gut_group.We identified 15 metabolites significantly correlated with both gut microbiota and laying performance,e.g.,DL-methionine sulfoxide,THJ2201 N-valerate metabolite,tetracarbonic acid,etc.In conclusion,ELE1000 improved laying performance in elderly laying hens by affecting intestinal morphology,barrier function,microbiota,and serum metabolite profiles.These findings suggest that ELE can be a beneficial feed additive for extending the peak producing period in aged laying hens.

杜仲叶提取物绿色合成纳米铂颗粒及其美白作用

以杜仲叶提取物为还原剂和稳定剂,采用一步法绿色合成纳米铂颗粒(PtNPs),通过单因素试验分析反应条件对PtNPs颜色和浓度的影响,并研究PtNPs对酪氨酸酶活性的影响。结果表明:在一定范围内改变反应条件可调控合成PtNPs的颜色和浓度,适宜反应条件为反应时间60 min、反应温度90℃、氯铂酸浓度3.5 mmol/L、杜仲叶提取物质量浓度10.0 mg/mL,在该条件下制备的PtNPs粒径平均尺寸为(2.27±0.65) nm,具有面心立方结构,分布较均匀;PtNPs对体外蘑菇酪氨酸酶活性有较强的抑制作用,IC50为(6.98±0.76)μg/mL,显著降低了A375细胞内酪氨酸酶活性和UVB诱导的黑色素含量,可达到美白皮肤的效果。

超声波-微波辅助提取杜仲叶多糖工艺优化及其体外抗凝血活性分析

为开发我国丰富的杜仲叶资源,研究超声波-微波辅助提取杜仲叶多糖的最优工艺条件及其理化性质和体外抗凝血活性。首先通过单因素实验确定超声波功率、提取温度、微波功率、料液比、提取时间等影响多糖得率因素的范围,然后通过Plackett-Burman试验筛选关键影响因素,再采用Box-Behnken试验对工艺条件进行优化,分析了所得杜仲叶精制多糖的分子量、单糖组成等理化性质及活化部分凝血酶原时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)等抗凝血指标。结果表明,料液比、提取时间、提取温度为关键影响因素,最优提取工艺条件为超声波功率130 W、提取温度49℃、微波功率200 W、料液比1:30(g:m L)、提取时间20 min。在此条件下,杜仲叶多糖的实际得率为4.02%±0.03%,与理论得率4.08%接近。所得杜仲叶精制多糖的重均分子质量(M_(w))为1653 kDa,单糖组成及摩尔比为果糖37.3%、葡萄糖35%、N-乙酰-D氨基葡萄糖14.6%、半乳糖8.6%、阿拉伯糖4.4%。分析结果显示,杜仲叶多糖为β型酸性多糖。与阴性对照相比,杜仲叶多糖能极显著延长APTT(P<0.01),而当杜仲叶多糖浓度为8 mg/mL时,PT、TT亦能极显著延长(P<0.01),说明杜仲叶多糖主要通过内源性途径影响凝血系统,同时也能够通过外源性、共同途径来影响凝血过程。此研究可为我国丰富的杜仲叶资源的高值化开发利用提供理论依据和技术参考。