冬虫夏草胞外多糖的体外抗氧化活性

研究了人工培养冬虫夏草胞外多糖的体外抗氧化活性。通过体外抗氧化模型和分光光度法研究了5种胞外多糖级分在不同体系中对超氧阴离子和羟自由基的清除作用、Trolox等价抗氧化能力。结果表明:胞外多糖各级分均能较好的清除O2-.、.OH和ABTS+.自由基,且级分EPS-1A-F3的作用效果强于其他各级分,进一步揭示其在膳食和理疗上具有潜在的应用价值。     

吲哚乙酸对冬虫夏草生物量、胞外多糖产量及其抗氧化性能的影响

通过在液体培养基中添加不同浓度的吲哚乙酸,研究吲哚乙酸对冬虫夏草生物量、胞外多糖产量及其抗氧化性能的影响。结果表明:适宜浓度的吲哚乙酸可以提高冬虫夏草的生物量和胞外多糖产量,并且随吲哚乙酸浓度的增加二者均呈先增后降的变化趋势,当浓度为2.5μg/m L时,生物量和胞外多糖产量均达到最高,分别为18.3g/L和2.9g/L,较不添加吲哚乙酸分别增加了6.3%和15.4%;同时,适宜浓度的吲哚乙酸还可以提高冬虫夏草胞外多糖的抗氧化性能,在1.0μg/m L和2.5μg/m L时,胞外多糖对羟基自由基和DPPH的清除率分别达到最高,为58.9%和56.6%。      

人工培养冬虫夏草胞外多糖的分离纯化研究

本文以乙醇沉淀法提取得到的人工培养冬虫夏草(Cs-HK1)粗胞外多糖为研究对象,采用DEAE-52纤维素(Cl-)离子交换柱层析和Sephadex G-100葡聚糖凝胶柱层析进行分离、纯化得到一水溶性胞外多糖分EPS-1A。紫外光谱、比旋光度和凝胶渗透色谱法研究表明该多糖为相对均一组分,中性糖含量为99.0%,重均相对分子质量为4.0×104。多糖特征反应表明该多糖为非淀粉类,不含单糖、糖醛酸、蛋白质、核酸和多酚类物质的中性多糖。     

乳酸菌胞外多糖的研究进展

介绍了乳酸菌胞外多糖的生物合成、分离、提纯及结构分析,生物功能特性及其应用。     

营养条件对灰树花产胞外多糖产量的影响

灰树花是一种营养丰富的食、药两用真菌 .灰树花胞外多糖是一种具有生理活性的真菌多糖 .作者研究了营养条件对灰树花产胞外多糖的影响 ,确定了合理的初始碳源、氮源、无机离子、生长因子的质量浓度 .进一步的正交试验表明 ,灰树花产胞外多糖较佳的培养基组合为 :葡萄糖 4 0g/L ,蛋白胨 5g/L、磷酸二氢钾 4 g/L ,硫酸镁 2 g/L、玉米浆 2 0 g/L .     

虎奶菇菌核多糖的溶液粘度及构象研究

用刚果红实验和圆二色光谱观察了不同条件下SHNP分子在溶液中的形貌特征,研究了不同溶液体系中虎奶菇菌核多糖SHNP的比浓粘度和粒度变化情况,以判断其分子的溶液构象。研究表明:温度、pH、变性剂、金属离子等外界条件均不同程度的影响SHNP溶液的比浓粘度;在pH为12时,SHNP聚集体的有效直径呈现最大化;刚果红实验和圆二色光谱分析表明,SHNP不具有三股螺旋结构,以无规线团链构象存在,pH、变性剂均可改变其构象。     

酸水解冬虫夏草胞外多糖的分子质量变化及动力学研究

以冬虫夏草胞外多糖为研究对象,通过凝胶渗透色谱分析酸水解多糖的分子质量、分子质量降解率(MWDR)和多分散指数(MW/Mn)的变化规律,并在此基础上探讨酸水解动力学。结果表明：酸水解可得到高分子质量和低分子质量两个多糖组分,高分子质量多糖组分的含量、分子质量和MW/Mn均随酸解时间的增加而减小,而MWDR呈线性增加趋势。低分子质量多糖组分含量随酸水解时间的增加而增加,分子质量基本维持在3.0kD;MWDR在0.5h内呈线性增加趋势,大于0.5h后基本维持在0.25。胞外多糖的酸水解模式为中心链断裂,符合假一级反应动力学方程,反应速率常数为3.24×10-2min-1,远小于随机链断裂的反应速率常数。     

虎奶菇菌核多糖的溶液粘度及构象研究

用刚果红实验和圆二色光谱观察了不同条件下SHNP分子在溶液中的形貌特征,研究了不同溶液体系中虎奶菇菌核多糖SHNP的比浓粘度和粒度变化情况,以判断其分子的溶液构象。研究表明:温度、pH、变性剂、金属离子等外界条件均不同程度的影响SHNP溶液的比浓粘度;在pH为12时,SHNP聚集体的有效直径呈现最大化;刚果红实验和圆二色光谱分析表明,SHNP不具有三股螺旋结构,以无规线团链构象存在,pH、变性剂均可改变其构象。      

液态发酵条件对灰树花产胞外多糖产量的影响

实验证明适合灰树花多糖生产的培养基组成为:葡萄糖22g/L,蛋白胨3g/L,KH2PO40.8g/L,MgSO40.12g/L,橄榄油1%;发酵参数为:初始pH6.0,温度25℃,装液量100mL/500mL,摇床转速140 r/min。其胞外多糖产量可以达到0.471g/L。     

乳酸菌胞外多糖发酵条件优化及对馒头品质的影响

从老面中分离出一株高产胞外多糖的乳酸菌L1,经鉴定为植物乳杆菌,研究结果表明:L1菌株在C∶N为2∶1、培养基的初始pH为6左右、培养温度为30℃、培养时间为18 h的条件下,产糖量最高,添加乳酸菌L1胞外多糖的馒头比容明显增大,白度略微增大,感官评分较高。     

冬虫夏草多糖的研究进展

多糖是冬虫夏草所含活性物质中最重要最丰富的类群之一,本文综述了冬虫夏草多糖的提取、结构和药理学活性的研究进展,并提出了目前冬虫夏草多糖研究中存在的问题,为冬虫夏草多糖的进一步研究开发提供依据。     

Differentiation of Cordyceps Sinensis by a PCR-Single-Stranded Conformation Polymorphism-Based Method and Characterization of the Fermented Products in Taiwan

Cordyceps sinensis (Berk.) Sacc., which is a part of traditional Chinese medicine, has been used as a tonic food and herbal medicine in Asia for centuries. C. sinensis is sold as powders, and the quality is often questionable. To confirm the quality of C. sinensis, products were purchased from different supermarkets in Taiwan. Product samples were analyzed using PCR-single-stranded conformation polymorphism (PCR-SSCP) assay based on internal transcribed spacer 2 (ITS2). PCR-SSCP patterns distinguished ten samples into six groups, but no sample was grouped with representative C. sinensis (rCS). Only two of the ten C. sinensis functional ingredient samples (CSFFMS) tested CB and ST, were similar to the reference product of C. sinensis. This in consistent result could be caused by poor fermentation control process, contamination of original marketing samples or adultration. Therefore, the use of PCR-SSCP could be used for species differentiation or the detection of mutations based on ITS2 region in C. sinensis. The method represents a potential novel means for the differentiation of Cordyceps herbal medicines/functional ingredients and could be used as a quality control in the Cordyceps fermentation industry.     

Differentiation of Cordyceps Sinensis by a PCR-Single-Stranded Conformation Polymorphism-Based Method and Characterization of the Fermented Products in Taiwan

Cordyceps sinensis (Berk.) Sacc., which is a part of traditional Chinese medicine, has been used as a tonic food and herbal medicine in Asia for centuries. C. sinensis is sold as powders, and the quality is often questionable. To confirm the quality of C. sinensis, products were purchased from different supermarkets in Taiwan. Product samples were analyzed using PCR-single-stranded conformation polymorphism (PCR-SSCP) assay based on internal transcribed spacer 2 (ITS2). PCR-SSCP patterns distinguished ten samples into six groups, but no sample was grouped with representative C. sinensis (rCS). Only two of the ten C. sinensis functional ingredient samples (CSFFMS) tested CB and ST, were similar to the reference product of C. sinensis. This in consistent result could be caused by poor fermentation control process, contamination of original marketing samples or adultration. Therefore, the use of PCR-SSCP could be used for species differentiation or the detection of mutations based on ITS2 region in C. sinensis. The method represents a potential novel means for the differentiation of Cordyceps herbal medicines/functional ingredients and could be used as a quality control in the Cordyceps fermentation industry.     

冬虫夏草与蛹虫草原生质体融合初探

采用正交设计和双灭活标记方法对冬虫夏草与蛹虫草进行原生质体融合研究,获得融合子。结果表明：最适融合条件为：40% PEG 与0.08mol/L Ca2+ 的混合溶液(pH7.0)助融,35℃融合20min,融合率为2.74 × 10-5;并用形态学、颉颃实验及分子生物学方法初步探讨了双亲和融合子三者之间的亲缘关系。     

HPLC-DAD测定人工北冬虫夏草中虫草素含量

建立了测定北冬虫夏草子实体中虫草素的高效液相色谱法.使用Eclipse XDB C18(4.6mm X 150mm,5μm)色谱柱,以水:甲醇:甲酸(95:4:1)为流动相,流速为0.8ml/min,25℃下检测.检测波长为260nm.结果表明:虫草素的平均回收率为100.8%,RSD值1.88%.此方法简单、可靠.     

冬虫夏草茶饮料风味研究

根据对白砂糖、柠檬酸的阈值测定结果,研究了以虫草和茶叶为原料的饮料的风味。正交试验结果表明：以茶汤50ml、虫草浸提液22.5ml的添加量,配制的虫草茶饮料风味最佳。     

Microwave‐Assisted Extraction,Chemical Structures,and Chain Conformation of Polysaccharides from a Novel Cordyceps Sinensis Fungus UM01

Cordyceps sinensis is a well‐known tonic food with broad medicinal properties. The aim of the present study was to investigate the optimization of microwave‐assisted extraction (MAE) and characterize chemical structures and chain conformation of polysaccharides from a novel C. sinensis fungus UM01. Ion‐exchange and gel filtration chromatography were used to purify the polysaccharides. The chemical structure of purified polysaccharide was determined through gas chromatography‐mass spectrometry. Moreover, high performance size exclusion chromatography combined with refractive index detector and multiangle laser light scattering were conducted to analyze the molecular weight (M_w) and chain conformation of purified polysaccharide. Based on the orthogonal design L₉, optimal MAE conditions could be obtained through 1300 W of microwave power, with a 5‐min irradiation time at a solid to water ratio of 1:60, generating the highest extraction yield of 6.20%. Subsequently, the polysaccharide UM01‐S1 was purified. The UM01‐S1 is a glucan‐type polysaccharide with a (1→4)‐β‐d ‐glucosyl backbone and branching points located at O‐3 of Glcp with a terminal‐d ‐Glcp. The M_w, radius of gyration (R_g) and hydrodynamic radius (R_h) of UM01‐S1 were determined as 5.442 × 10⁶ Da, 21.8 and 20.2 nm, respectively. Using the polymer solution theory, the exponent (ν) value of the power law function was calculated as 0.38, and the shape factor (ρ = R_g/R_h) was 1.079, indicating that UM01‐S1 has a sphere‐like conformation with a branched structure in an aqueous solution. These results provide fundamental information for the future application of polysaccharides from cultured C. sinensis in health and functional food area.     

虫草与富硒虫草多糖的体外抗氧化活性

采用Fenton法和邻苯三酚自氧化法测定虫草和富硒虫草多糖对.OH、O2-.和H2O2的清除率。结果表明:虫草多糖对O-2.和H2O2的清除能力依次为富硒虫草胞外多糖>富硒虫草胞内多糖>虫草胞外多糖>虫草胞内多糖,而对.OH的清除能力依次为:富硒虫草胞外多糖>虫草胞外多糖>富硒虫草胞内多糖>虫草胞内多糖;当100mg/L多糖溶液添加量分别高于80、40、90μL时,各组多糖对.OH、O2-.和H2O2 3种自由基的抑制率均可高于50%。