A rapid quantitative method for polysaccharides in green tea and oolong tea

Tea polysaccharides (TPS) from five different kinds of tea contain similar composition of sugars and amino acids. Polysaccharide part of TPS is mainly composed of arabinose, galactose and glucose with the approximate molar ratio of 1:1:0.5. Protein part of TPS is composed of 16 normal amino acids among which Val, Ala, Gly, Glu are the major proportion. Based on the results, the purified TPS was used as the calibration standard in phenol sulfuric acid reaction for the calibration curve that was constructed by plotting absorbance versus mass of TPS with a correlation coefficient of 0.9961. In the developed method, TPS mass recovery ranges from 84.88 to 95.7% with a relative standard deviation of 5.53%. It is found that the developed method is simple, rapid, reliable and is ideally suitable for quantifying TPS from green tea or oolong tea.     

银耳多糖的提取、分离、纯化及其功能性质研究

本实验研究了银耳多糖的提取、分离、纯化及其功能性质.结果表明,酶法浸提效果优于碱浸提法,酶法提取银耳多糖溶液的最适条件为:料水比1∶60,加入0.7%的果胶酶,酶解50min,浸提时间60min;银耳多糖通过DEAE-Sepharose Fast Flow和SephadexG-200柱层析后可得到纯度较高的TPP2多糖.TPP2具有极强的清除DPPH·的活性,DPPH·清除一半时的TPP2浓度为55μg/m(IC50).     

红曲多糖的免疫活性研究

选择淋巴器官脏体指数、迟发型变态反应、脾脏抗体生成细胞数、巨噬细胞吞噬指数等免疫学指标观察红曲多糖对昆明种小白鼠免疫功能的影响.结果表明,通过DTH试验,小鼠经灌胃红曲多糖后,其足跖肿胀度与对照组差异明显,说明红曲多糖能提高小鼠细胞免疫功能.碳粒廓清试验,廓清速率大幅增加表明红曲多糖可提高腹腔巨噬细胞吞噬能力,促使小鼠外周血E-玫瑰环形成,增加体内淋巴细胞转化率,使非特异性免疫加强.淋巴细胞脏体指数较对照组差异明显以及脾脏抗体生成细胞检测结果表明,红曲多糖对小鼠的细胞免疫和体液免疫有一定的增强作用.     

膜分离技术提取枸杞多糖的工艺

采用微滤、超滤操作对枸杞多糖提取液进行了处理,结果表明：操作压力、操作时间及料液温度对膜通量有很大的影响．由微滤和超滤相结合对枸杞多糖的截留率可达到90．4％．枸杞多糖的定量测定采用硫酸-苯酚显色法;枸杞多糖的相对分子量测定采用凝胶渗透色谱法。     

纤维素酶辅助提取茶树菇多糖的研究

通过单因素及正交试验研究纤维素酶酶解辅助提取茶树菇子实体多糖的最佳工艺。研究结果表明:水浴提取茶树菇子实体多糖料液比为1∶60,提取时间120m in,温度为60℃时提取效果最佳;纤维素酶酶解辅助提取茶树菇子实体多糖,料液比为1∶80,酶浓度1.5%,浸提液pH 6.0,提取温度50℃。对2种提取法进行了比较,水浴法提取茶树菇多糖的平均提取率为1.40%;纤维素酶酶解辅助提取茶树菇多糖的平均提取率2.38%,比水浴法提高了70.47%。纤维素酶酶解辅助提取茶树菇多糖明显优与水浴法。     

牛肝菌多糖的含量测定

苯酚-硫酸法是测定多糖的常用方法,影响该法显色的因素较多,对不同多糖物质,其最佳显色条件不同。采用正交试验设计法确定牛肝菌多糖的最佳显色条件。结果表明,在显色时间25m in、显色温度70℃、苯酚1.2mL、硫酸8.0mL条件下,采用苯酚-硫酸法测定牛肝菌多糖含量时,平均回收率达99.0%,RSD3.70%(n=6)。     

Role of pectic polysaccharides in structural integrity of apple cell wall material

Texture modulating properties of aqueous dispersions of apple cell wall material differed from those of tomato or kiwifruit, particularly under high shear. It was previously hypothesized that this may be due to the fact that the apple cell wall showed less in vivo solubilization of pectic polysaccharides during ripening compared to tomato or kiwifruit. However, in vitro solubilization of the pectic polysaccharide content of apple CWM by endo-polygalacturonase and/or extraction with 0.05 M sodium carbonate, did not affect the loss in wall integrity shown by tomato or kiwifruit CWMs under shear. In addition, the pectin-depleted residue after Na₂CO₃ extraction possessed better water retaining and viscosity generating properties than the original cell wall material. Following treatment of apple CWM with cellulase, the viscosity of suspensions decreased, emphasising the role that the cellulose–hemicellulose network plays in the water-retaining capacity of the cell wall. Residue from CWM after cellulase treatment consisted of ∼85% pectic polysaccharides. Surprisingly, the integrity of these “cellulose-free” walls was maintained after shear. It is concluded that differences in structural properties of the CWMs of apple compared to kiwifruit or tomato are not simply related to pectin solubilization but to a fundamental difference in the architecture of the apple cell wall.     

超声波法提取香菇培养基废弃物中活性多糖的研究

为了更好的开发利用香菇资源,本研究以香菇培养基废弃物为材料、多糖为研究对象,通过对比分析和L9(34)正交试验设计等研究方法,重点考察不同超声功率、料液比、超声时间对香菇培养基废弃物中多糖提取率的影响。结果表明,最佳提取工艺条件为超声时间45min,料液比1:30,超声功率300W,多糖提取率平均可达3.46%。     

桦褐孔菌菌粉多糖提取工艺的优化

根据Box-Benhnken的中心组合实验设计原理,在单因素试验的基础上采用三因素三水平的响应面分析法,以多糖提取率为响应值作响应面,并进行回归分析。结果表明,桦褐孔菌菌粉多糖提取的理想工艺条件为:温度为83℃,提取时间为2.2 h,液料比为33.3∶1时,桦褐孔菌菌粉多糖的提取率达到24.578%。气相色谱分析该工艺条件下提取的桦褐孔菌菌粉多糖,各主要单糖组成及质量分数分别为:阿拉伯单糖0.53%,甘露糖0.48%,葡萄糖10.75%,半乳糖2.44%。红外光谱分析结果显示,多糖产品中含有酸性多糖,糖苷键主要是α型。     

真姬菇多糖的分离纯化及结构分析

以真姬菇(Hypsizigus marmoreus)子实体为材料提取粗多糖。用Sevage法脱蛋白,活性炭脱色,经DEAE-纤维素柱(D3.5 cm×60 cm)层析得真姬菇纯化多糖HPS-Ⅰ和HPS-Ⅱ。经SephadexG-200凝胶柱(D1.6×30 cm)层析,证明HPS-Ⅱ为单一组分。元素分析结果表明,HPS-Ⅱ不含氮、磷、硫,碳和氢的含量分别是37.81%和6.737%。采用Sepharose CL-4B凝胶柱(D1.6×30 cm)层析,以Dextran多糖为标准品,测得HPS-Ⅱ的平均分子量为4.61×105。经红外光谱和1H NMR和13C NMR谱分析确定HPS-Ⅱ为以(1→4)-α-D-Glep为主链,(1→6)-α-D-Glep为侧链的α-D-吡喃葡聚糖。