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.

Cloning and Function Identification of a Phytoene Desaturase Gene from Eucommia ulmoides

The phytoene desaturase(PDS)encodes a crucial enzyme in the carotenoid biosynthesis pathway.Silencing or inhibiting PDS expression leads to the appearance of mottled,chlorosis,or albino leaves.In this study,the CDS sequence of EuPDS(Eucommia ulmoides Phytoene Desaturase)was first cloned and then PDS was silenced in Nicotiana benthamiana.Result showed the expression level of EuPDS in leaves was higher than that in the roots and stems.In N.benthamiana leaves,which were treated by Agrobacterium for 24 h,photo-bleaching was shown on the fresh leaves one week after injection and the transcript level of PDS was down-regulated during the period of emersion.This suggested that EuPDS could silence PDS of N.benthamiana,so as to cause the phenotype of leaf whitening.PDS is the main reporter gene involved in virus-induced gene silencing(VIGS).This study offered molecular evidence for identifying PDS gene involved in Carotenoid’s biosynthesis pathway and the regulation networks in E.ulmides.It also laid a useful foundation for study on leaf discoloration mechanism of other woody plants.

Overexpression ofβ-1,4-Glucanase Gene EuEG1 Improves Micrografting of Eucommia ulmoides

Adventitious root formation poses a major constraint on the tissue culture and genetic transformation of Eucommia ulmoides.Micrografting offers a new method for the transplantation of genetic transformation,and its success depends on the formation of graft unions.This study used transgenic rootless test-tube seedlings as scions and seedlings from seed as rootstocks during micrografting to avoid the rooting issues that occur during tissue culture and to investigate the role of the EuEG1 gene in the graft healing process.We found that the EuEG1 gene is a vital regulator of graft,and its overexpression contributes to the survival of Eucommia ulmoides micrografting.The EuEG1 gene transgenic plants(TP)used as scions for micrografting presented a significantly higher survival rate than the wild type(WT)and empty vector(EV)regenerated scions.During the grafting healing process,the expression of the EuEG1 gene was higher during the period of callus proliferation,suggesting that the EuEG1 gene was involved in the graft healing process.Histological observation revealed that more calluses tissue appeared at the junction of transgenic scions,and the connection with the rootstock was stronger,which benefits wound healing.These results provide new insights into Eucommia ulmoides micrografting and indicate that the EuEG1 gene can promote wound healing and improve the micrografting survival rate.

Effects of Fatigue Characteristics on Static and Dynamic Performance of Eucommia Rubber Isolators

This study aimed to investigate the effect of fatigue characteristics on the static and dynamic performance of Eucommia ulmoides gum isolators, and to explore the performance changes of Eucommia ulmoides gum isolators with different formulations. For this purpose, we used five formulations of Eucommia ulmoides gum isolators and set different fatigue test methods to study the static and dynamic performance changes of Eucommia ulmoides gum isolators with different formulations by changing the amplitude. The experimental results showed that the addition of Eucommia ulmoides gum had an impact on the performance of the isolator, and the number of fatigue cycles would lead to the hardening of the Eucommia ulmoides gum isolator and changes in its static and dynamic performance. In the range of two million vibrations, the performance change of the isolator was significant in the early stage and then tended to be flat, indicating that the impact of fatigue on the performance of the isolator would not continue to persist. It is worth noting that the study found that the addition of 30% Eucommia ulmoides gum had the least impact on the performance of the isolator under fatigue. Therefore, for long-term use of Eucommia ulmoides gum isolators, attention should be paid to their fatigue characteristics to ensure their stability and reliability. Additionally, this study provides a reference for the design and application of Eucommia ulmoides gum isolators. In summary, this study provides important reference value for a deeper understanding of the fatigue characteristics of Eucommia ulmoides gum isolators and for ensuring their stable and reliable performance. .

Role and Effects of Eucommia ulmoides Leaves in the Growth Process of Livestock and Poultry

Substitutes of feed antibiotics have been a key research topic in the new stage of animal husbandry.Chinese veterinary medicine refers to decoction pieces and their preparations processed from natural plants,animals,and minerals and used for animal disease prevention and improvement of animal production performance under the guidance of Chinese veterinary pharmacy theory.Eucommia ulmoides leaf extract has many active functional components such as chlorogenic acid,E.ulmoides polysaccharides and flavonoids,which have many biological properties such as antibacterial,antioxidant,immune-regulation,sugar ester-and bone metabolism-regulation effects.This paper explored active ingredients and biological properties of E.ulmoides leaf extract,as well as its role and effects in livestock and poultry breeding,providing a scientific basis for the use of E.ulmoides leaves in livestock and poultry breeding.

基于UHPLC-Q-Exactive Orbitrap HRMS技术结合化学计量学方法的不同干燥处理杜仲叶成分分析

采用基于液质联用的非靶向代谢组学技术结合化学计量学数据自动解析软件AntDAS-LCHRMS分析了4种不同干燥处理(冻干、热泵烘干、电热烘干、晒干)杜仲叶样本中的化合物。杜仲叶样本数据由超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UHPLC-Q-Exactive Orbitrap HRMS)分别在正、负离子模式下进行采集,经AntDAS-LCHRMS软件解析,共鉴定出71种差异性化合物,经标准品验证确定40种化合物,包括环烯醚萜类、有机酸类、黄酮类、氨基酸类、核苷类、维生素类等9类物质。其中,正、负离子模式下均可识别并验证的化合物有车叶草苷、绿原酸、芦丁、异槲皮苷、车叶草苷酸、京尼平苷等25种化合物。层次聚类分析(HCA)及主成分分析(PCA)结果均显示,相同处理的杜仲叶样本各自聚成一类,不同处理的杜仲叶样本可明显区分。热图分析进一步揭示了不同干燥处理杜仲叶样本中差异性化合物的含量变化。晒干处理样本中苯丙氨酸及色氨酸等氨基酸类物质的水平较高;冻干及热泵烘干处理样本中有机酸类、环烯醚萜类、糖类等含量较高;电热烘干样本中核苷类、黄酮类物质的含量较高;黄酮类物质在冻干、热泵烘干及晒干样本中差异较小。研究结果为不同干燥处理杜仲叶的成分分析、品质评价及其开发应用提供了科学依据,也可为其他复杂药用植物体系的化学成分分析提供参考。

不同良种杜仲叶主要营养成分的动态变化与综合评价

[目的]杜仲Eucommia ulmoides叶在医疗、保健、食品及无抗养殖等领域有广泛用途。通过比较不同良种杜仲叶主要营养成分的差异及动态变化,筛选优质叶用杜仲良种资源,为杜仲叶的高效利用提供参考。[方法]分别利用HPLC法和全自动氨基酸分析仪测定13个良种不同生长期杜仲叶9种重要活性成分和15种氨基酸组分的含量,基于主成分分析和隶属函数法开展不同良种杜仲叶的营养评价。[结果]与槲皮素、桃叶珊瑚苷和京尼平苷酸相比,原儿茶酸、芦丁、绿原酸、紫云英苷、山奈酚以及松脂素二葡萄糖苷的含量在不同良种杜仲叶之间差异较大;不同良种同一活性成分含量的生长动态变化趋势基本一致。13个良种杜仲叶必需氨基酸与总氨基酸的比值(EAA/TAA)为0.40~0.45,必需氨基酸与非必需氨基酸的比值(EAA/NEAA)为0.66~0.82;天冬氨酸、苏氨酸、丝氨酸等5种氨基酸的动态变化趋势较为一致。总氨基酸、必需氨基酸、亮氨酸等9种组分的含量可作为杜仲叶营养价值的评判指标。[结论]13个良种杜仲叶的氨基酸组成和比例均达到理想蛋白质模式的标准。‘华仲10号’‘华仲24号’‘华仲13号’‘华仲30号’‘华仲12号’是优质的叶用杜仲良种资源,在规模化提取和利用杜仲叶黄酮类时应优先选用‘华仲12号’‘华仲24号’良种。

杜仲协同拟茎点霉XP-8合成木脂素类的条件优化及其功能活性

对杜仲协同拟茎点霉XP-8生物合成松脂醇(Pinoresinol,Pin)、松脂醇单葡萄糖苷(Pinoresinol-4-O-β-Dglucopyranoside,PMG)和松脂醇二葡萄糖苷(Pinoresinol diglucoside,PDG)的条件进行优化,研究培养方式、杜仲添加量和静息处理时间对Pin、PMG和PDG产量的影响,并对相关产物的抗氧化性和抑癌性进行研究。结果表明,3%杜仲PDB培养基培养菌体并静息处理5 d时Pin、PMG和PDG产量较高。该条件下代谢产物液对DPPH和ABTS+自由基的清除能力显著高于杜仲空白培养基,说明发酵过程中产生了增强抗氧化功能的物质。其还能抑制肝癌细胞HepG-2的增殖,通过纯品验证活性说明,Pin是其中主要抑制癌细胞的活性成分,代谢产物液抑制肝癌细胞的作用是一种协同效应。

杜仲改善大鼠产后抑郁的作用机制研究

目的 探讨杜仲改善大鼠产后抑郁的作用机制。方法 受孕雌鼠随机分为正常组、产后抑郁组和杜仲低、高剂量组(1.34、2.68 g/kg,以生药计),每组10只。除正常组外其余各组大鼠运用孕期旁观电击法建立产后抑郁大鼠模型;造模的同时,给药组大鼠灌胃相应药物,正常组及产后抑郁组大鼠灌胃生理盐水,持续21 d。观察各组大鼠实验期间的一般情况,通过旷场实验、Morris水迷宫实验和糖水偏好实验进行行为学评价,检测各组大鼠血清中皮质酮(CORT)、下丘脑中促肾上腺皮质激素释放因子(CRF)和尿皮质素(UCN)、垂体中促肾上腺皮质激素(ACTH)水平,以及海马组织中CRF受体1(CRFR1)、CRFR2及电压依赖性阴离子通道1(VDAC1)蛋白表达水平,海马组织凋亡细胞比例及JC-1高电位细胞比例,并观察海马组织形态。结果 与产后抑郁组比较,杜仲高剂量组大鼠食欲、精神、毛色均有所改善,体重有所增加;垂直运动、水平运动、自我梳理得分均显著升高(P<0.05);第2~4天逃避潜伏期均显著缩短;穿越平台次数显著增加,每次穿越时间显著延长(P<0.05);孕20 d及产后30 d糖水消耗比率显著升高(P<0.05);CRF、UCN、ACTH、CORT水平,噬仔率,CRFR2、VDAC1蛋白表达水平,海马组织凋亡细胞比例均显著降低(P<0.05);JC-1高电位细胞比例显著升高(P<0.05);神经元细胞周围水肿现象明显改善。结论 杜仲可能通过抑制下丘脑-垂体-肾上腺轴的过度激活,降低CRFR2的表达水平,进而抑制VDAC1的表达,并减少神经元细胞的凋亡,从而改善产后抑郁症状。

超声处理对杜仲籽仁蛋白结构及理化特性的影响

旨在为杜仲籽仁蛋白的开发与应用提供参考,以杜仲籽仁粕为原料,采用碱溶酸沉法提取蛋白,采用500 W、35 kHz超声波对杜仲籽仁蛋白处理不同的时间(0、10、20、30 min和40 min),探究超声处理对杜仲籽仁蛋白微观结构、理化特性(粒径、Zeta-电位、内源荧光光谱、溶解性、持水性、持油性、起泡性、起泡稳定性、乳化性、乳化稳定性)的影响。结果表明:超声处理可改变杜仲籽仁蛋白的微观结构、粒径、Zeta-电位和荧光强度;超声处理20 min时,杜仲籽仁蛋白溶解度达到75.35%;超声处理10 min时,杜仲籽仁蛋白乳化性最大,达到72.12 m^(2)/g;超声处理40 min时,杜仲籽仁蛋白持水性、持油性、起泡性和起泡稳定性最大,分别达到4.32 g/g、3.46 g/g、23.12%和21.12%。综上,超声处理可改善杜仲籽仁蛋白的持水性、持油性、起泡性、乳化性等功能特性。

基于电子鼻和HS-SPME-GC-MS分析蒸汽爆破对杜仲嫩叶和成熟叶茶香气特征的影响

为探究蒸汽爆破(汽爆)辅助加工制成杜仲叶茶的挥发性成分差异和主要呈香特征,以杜仲‘华仲8号’嫩叶和成熟叶为对象,采用汽爆技术对杜仲叶进行处理,基于电子鼻和顶空固相微萃取-气相色谱-质谱(headspace solid-phase microextraction combined with gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用法解析汽爆对两种杜仲茶香气特征的影响。主成分分析和线性判别分析对电子鼻数据模型拟合度高,杜仲嫩叶和成熟叶茶汽爆前后香气特征均存在显著差异。HS-SPME-GC-MS检测共鉴定出177种挥发性成分,通过正交偏最小二乘判别分析(变量重要性投影值≥1)以及Kruskal-WallisH检验(P<0.05)进一步筛选出24种香气物质,发现汽爆前嫩叶茶关键香气物质为二氢猕猴桃内酯。汽爆后嫩叶茶关键呈香物质在此基础上增加了壬醛、苯甲醛和苯乙醛,呈现柑橘香、花香、焦糖香、苦杏仁味、坚果香、玫瑰香和巧克力香。汽爆前成熟叶茶无关键香气物质,汽爆后成熟叶茶关键香气物质为二氢猕猴桃内酯和壬醛,呈现甜桃香、木香、柑橘香、花香和焦糖香。研究结果可为开发杜仲叶茶饮品提供参考依据。

中药复方治疗原发性骨质疏松用药规律及作用机制分析

背景:中药复方治疗原发性骨质疏松有着较久的历史,并且疗效确切,但其用药规律及作用机制尚不明确。目的:利用数据挖掘与网络药理学的方法学,探究现代中医家治疗原发性骨质疏松的用药规律、分子层面的作用机制并一定程度的加以验证。方法:将中国知网、万方、维普、PubMed等数据库收录的相关文献作为数据来源,使用Microsoft EXCEL 2019、IBM SPSS 25.0等软件统计和提取相关资料。将数据统计得到的高频药物进行关联规则分析和聚类分析,综合两者结果得到中药复方治疗原发性骨质疏松的核心药物组合,利用网络药理学阐释此组合发挥治疗作用的机制并借助分子对接加以验证。结果与结论:最终纳入151篇文献,筛选出方剂207首,涉及中药285味。①通过上述两种分析综合得到重要药物组合10组,其中置信度和提升度最高的核心药物组合为“骨碎补-杜仲-当归”,其组合治疗原发性骨质疏松的关键成分为槲皮素、山奈酚、柚皮素等,核心靶点为SRC原癌基因(SRC proto-oncogene)、磷脂酰肌醇-3-激酶调节亚单位1(PIK3R1)、RELA原癌基因(RELA)等,主要通路为癌症信号通路、JAK-STAT信号通路、VEGF信号通路、核因子κB信号通路等。②将关键活性成分与核心靶点进行分子对接,两者展示出较好的结合性。③中药复方治疗原发性骨质疏松核心药物组合可利用其多种活性成分,通过多条信号通路、作用于多个靶点发挥疗效,可为后续治疗原发性骨质疏松新药的研发提供理论基础。

南方红壤区杜仲(Eucommia ulmoides)树干液流动态

采用根据热平衡原理设计的热扩散探针(Thermal dissipation sap flow velocity probe,TDP),于2004年7月到10月对南方红壤区的杜仲人工林的树干液流进行连续监测,结合所测定的相关因子,分析杜仲液流的变化规律及其与各因子的关系。结果表明,在不同月份,杜仲液流速率的日变化规律基本一致,呈单峰曲线,但是树干液流在启动时间、峰值出现时间上存在差异;从7月到10月份,杜仲树干液流速率逐渐增大,10月份液流速率达到1.818 g/(cm2.h);杜仲液流速率与太阳辐射、空气相对湿度、温度、风速等气象因子相关性显著,但是太阳辐射和空气相对湿度是影响杜仲液流的重要因子,其中7月到9月份,太阳辐射是主要影响因子,而10月份,空气相对湿度占主导地位;树干液流与胸径、冠层厚度以及胸径平方与树高之积呈现出显著的相关性。

杜仲对黄曲霉的抑制及在养殖中的有益作用

饲料中黄曲霉污染严重制约了饲料业和养殖业的高质量发展,在我国目前饲料端全面禁抗背景下,天然植物原料作为理想的抗生素替代品被推崇。杜仲是我国传统的药食两用植物资源,将其提取物或原粉添加到饲料中可有效遏制黄曲霉污染,并提高畜禽品质,是理想的饲料替抗物。文章阐述了杜仲提取物及其活性成分对黄曲霉的抑制作用以及在养殖中的有益作用,旨在为其在饲料行业中的应用推广提供参考。

新疆不同杜仲品种光合特性分析及生产性能比较

本研究旨在综合分析塔城地区沙湾市试种的4个杜仲品种的光合特性和生产性能。在杜仲光合活跃期(6月)测定4个杜仲品种叶片的叶绿素浓度、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)以及胞间CO_(2)浓度(Ci)、叶片数量和叶片长宽,采收后(10月)对其单株叶片的鲜重和干重以及叶片内的粗蛋白、粗脂肪、总糖、木脂素、绿原酸、总黄酮含量进行检测,并进行方差分析、相关分析和主成分分析。研究发现,由于塔城地区干旱的原因,抗旱性较好的‘秦仲2号’‘、秦仲3号’综合光合性能优于‘秦仲1号’‘、秦仲4号’。4个杜仲品种粗蛋白、粗脂肪和总糖含量分别为417.87~456.97、265.63~317.31、68.47~79.19 mg/g,木脂素、绿原酸和总黄酮含量区间分别73.26~78.89、3.04~3.76、1.66~1.96 mg/g。主成分分析发现,‘秦仲3号’的综合得分最高,生产性能最好。在6月Pn最高的品种是‘秦仲2号’,光合性能最优,其余3个品种Pn无显著性差异。‘秦仲1号’叶产量和质量均较低,‘秦仲2号’和‘秦仲3号’的单株叶片干重同为4个品种中最高,‘秦仲3号’相对‘秦仲2号’品质更高;‘秦仲4号’的营养含量高,但叶产量极低。综上所述,‘秦仲3号’最适合作为塔城地区的叶用杜仲品种。

β-谷甾醇改善绝经后骨质疏松的实验研究

[目的]探究杜仲有效单体成分β-谷甾醇对小鼠绝经后骨质疏松的疗效及其潜在作用机制。[方法]将24只12周龄雌性C57BL/6J小鼠随机分为假手术组、模型组及β-谷甾醇干预组,每组8只,采用双侧卵巢切除术建立绝经后骨质疏松模型,术后假手术组及模型组给予0.9%氯化钠溶液灌胃,β-谷甾醇干预组给予β-谷甾醇灌胃,术后8周将各组小鼠处死取材,借助显微计算机断层扫描(micro-computed tomography,Micro-CT)观察β-谷甾醇干预对绝经后骨量丢失及骨小梁破坏的保护作用,并采用苏木素-伊红(hematoxylin-eosin,HE)染色对小鼠股骨远端区域进行组织形态学分析,同时通过抗酒石酸酸性磷酸酶(tartrate-resistant acid phosphatase,TRAP)染色及碱性磷酸酶(alkaline phosphatase,ALP)染色评估小鼠骨吸收与骨形成情况,并通过免疫组化检测各组样本的β-catenin表达水平。[结果]Micro-CT扫描结果显示,β-谷甾醇干预可减少绝经后骨量丢失及骨微结构破坏,HE染色证实β-谷甾醇可有效维持骨小梁数目及组织形态,并在一定程度上抑制雌激素缺乏引起的异常脂肪堆积现象。TRAP染色结果表明,β-谷甾醇并不影响破骨细胞形成,而免疫组化结果表明β-谷甾醇可显著促进成骨标志物ALP的表达。与此同时,β-谷甾醇可增加β-catenin在股骨远端区域的表达,提示β-谷甾醇促进骨形成,可能与其上调β-catenin信号通路有关。[结论]β-谷甾醇体内干预可上调β-catenin信号通路,增强成骨分化,促进机体骨形成,从而改善绝经后骨质疏松。

地面覆盖对皮叶两用杜仲(Eucommia ulmoides Oliv.)林冠层辐射能分布的影响(英文)

通过在杜仲林地种植白三叶草、覆膜和覆秸秆,研究了地面覆盖对8a生皮叶两用杜仲林冠层光能分布的影响。结果表明:地面种植白三叶草、覆膜、覆秸秆和不覆盖条件下,林冠中部的总辐射分别比林冠表面降低了18.8%、20.0%、17.1%、17.1%;在林冠层,不同地面覆盖的林冠下表面接受的地面反射辐射差异较大,种植白三叶草、覆膜和覆秸秆的林冠下表面接收的反射辐射分别较地面无覆盖的高42.8%、56.4%和8.1%,且林冠中部接受的地面反射辐射明显低于林冠下表面;种植白三叶草、覆膜和覆秸秆的林冠中部的净辐射能分别较地面无覆盖的高14.4%、18.5%和5.6%。不同覆盖处理的冠层净辐射垂直分布趋势基本一致,在冠层范围内,净辐射能随高度升高呈指数规律增大。

基于超高效液相色谱—串联质谱同时测定大鼠血浆中杜仲制剂的药代动力学研究

目的 建立用于血浆中杜仲各成分含量测定的超高效液相色谱—串联质谱的方法,并进行杜仲及其制剂各成分的药代动力学研究。方法 SD大鼠口服不同的杜仲制剂后,于不同的时间点收集血浆样品,以0.1%甲酸水溶液(A)-0.1%甲酸乙腈(B)为流动相,梯度洗脱,采用安捷伦SB C_(18)色谱柱(2.1 mm×50 mm, 1.8μm)进行分离;在多反应监测模式下,负离子模式测定;通过Phoenix Winnonlin 8.1软件计算药代动力学参数。结果 原儿茶酸、京尼平苷酸、松脂醇二葡萄糖苷、无梗五加苷、松脂醇葡萄糖苷、京尼平苷、绿原酸、咖啡酸分别在3.2-2000,3.3-2044,0.6-2028, 0.6-1770,0.3-2036,0.6-2004,0.5-1596,0.7-1090 ng/mL范围内,线性良好;专属性、准确度、精密度、稳定性、回收率和基质效应均符合生物样本检定要求。采用非房室模型分析,8个成分在AUC_(0-∞)、t_(1/2z)、T_(max)、C_(max)、V_(z)/F、Cl_(z)/F、MRT_(0-∞)方面均不相同。结论 该方法灵敏度高、专属性强、准确性好,可用于杜仲成分在大鼠体内的药代动力学研究。不同杜仲制剂在大鼠体内的释药速度、起效快慢及作用强度均不相同,在临床应用上具有指导意义。

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。

杜仲叶化学成分、药理活性及现代应用研究进展

杜仲叶是一种传统中药,现收录于《中华人民共和国药典》一部,同时其作为一种药食两用中药,具有较高的研究价值和开发潜力。现代研究表明,杜仲叶主要含有黄酮类、酚酸类、木脂素类、环烯醚萜类等化学成分,具有抗氧化、降血压、降血脂、神经保护和骨保护等药理作用。目前已研制和开发出较多以杜仲叶为主药或原料的药品、保健品和食品,在医疗、化工和养殖业等多个领域均有应用。该文通过检索近20年国内外对杜仲叶的相关研究报道,对其化学成分、药理活性和应用进行整理总结,为后续杜仲叶的研究及资源开发提供科学依据。