Biologically Active Substances from Cacalia hastate Leaves. 1. Carbohydrates from Leaves and Their Hypoglycemic Activity

Leaves of Cacalia hastate L. (Asteraceae) were composed of free sugars, water-soluble polysaccharides (arabinogalactan type), pectinic substances, hemicelluloses, and cellulose. The hypoglycemic activity was determined for the water-soluble polysaccharides and pectinic substances.     

Medium optimization for polysaccharide production of Cordyceps sinensis

As a potential anticarcinogenic agent, polysaccharides from Cordyceps sinensis have been demonstrated to possess strong antioxidation activity. The aim of the present research was to study the optimal medium to produce polysaccharides of C. sinensis by using response surface methodology (RSM). The composition of optimized medium for polysaccharide production calculated from the regression model of RSM was 6.17% sucrose, 0.53% corn steep powder, 0.5% (NH₄)₂HPO₄, and 0.15% KH₂PO₄ at pH 4.44, with a predicted maximum polysaccharide production of 3.17 g/L. When applying this optimal medium, the maximum polysaccharide production was 3.05 and 3.21 g/L in a shake flask and a 5-L jar fermentor, respectively. When the pH was controlled at a higher level such as pH 5.0, both cell growth and polysaccharide production were inhibited. A low pH of 2.85 was required for maximum production of polysaccharides.     

海水小球藻中多糖的提取及其单糖组成的气相色谱-质谱分析

在温度为70℃、功率为600 W、提取时间为30 m in的条件下,海水小球藻中的多糖可以得到较好的提取。经过优化,当超声波作用时间为90 m in、超声波功率为300 W、水解液为1 mol/L乙酸时,小球藻多糖的超声水解效果最好。碱提、水提、酸提海水小球藻多糖中的单糖组成,经过GC-MS分析,它们的单糖组成各不相同。碱提粗多糖中所含单糖为鼠李糖、L-岩藻糖、D-阿拉伯糖、D( )-木糖、D-甘露糖、D-葡萄糖、D-半乳糖,各单糖百分含量分别为20.68%、0.32%、1.0%、2.20%、4.58%、50.28%、20.91%(W/W);水提海水小球藻粗多糖中含鼠李糖、核糖、岩藻糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖8种单糖,它们百分比分别为2.32、2.36、0.24、0.89、0.56、3.44、78.21、11.99%(W/W);酸提粗多糖中所含单糖为鼠李糖、核糖、岩藻糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖,各单糖百分含量分别为2.75、1.75、0.23、1.04、0.61、5.99、74.33、13.30%(W/W)。本实验所建立的微波辅助提取、超声水解多糖、GC-MS分析多糖中的单糖组成等方法,具有简便、快速、准确的特点。可用于海藻和其它植物中的多糖研究。     

New polysaccharide-g-polyacrylonitrile copolymers: synthesis and thermal characterization

Various natural and modified polysaccharides (i.e. arabic gum, tragacanth gum, xanthan gum, sodium alginate, chitosan, sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose) were modified using ceric-initiated graft polymerization of acrylonitrile under inert atmosphere. Grafting was confirmed using spectral (FT-IR) proofs. The grafting parameters were determined by conventional methods. Thermal characteristics of the homopolymer-free copolymers were studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) under nitrogen atmosphere. The major thermal transitions as well as the activation energy of the major decomposition stages were investigated. The polyacrylonitrile (PAN)-grafted polysaccharides were recognized to be thermally stable more than the corresponding non-grafted substrates, although they begin to decompose at relatively lower temperatures than the non-grafted counterparts. Copyright © 2003 John Wiley & Sons, Ltd.     

Glucofructans from <Emphasis Type="Italic">Cousinii radians</Emphasis> roots

Structures of glucofructans isolated from Cousinii radians roots were studied by methylation, periodate oxidation, and IR and ¹³C NMR spectroscopies. It was found that fructofuranose units were bonded to each other by inulin-type β-(2→1)-gylcoside bonds. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–5, January–February, 2007.     

Studies on the Peptides and Polysaccharides in Pollen

The peptides RP3I and PSPP1-4 were purified from the rape and the Papaver Somniferunpollens, respectively. Their sequences and physiological activities were determined and synthesized ex-cept PSPP1. The polysaccharides TAA-C and CPA-E were obtained from Typha Angustifilia andCodonopsis Pilosula pollens, respectively. Their partial characterization and structures were studied.     

New methodology for tosylation of hydroxylic supports as exemplified by the immobilization of micrococcal endonuclease on agarose

Improvement have been made in a simplified procedure we previously reported (J.Mol.Catal. (1986),38,227 for the activation of tosyl chloride of supports possessing primary hydroxyl groups. The method is simple, can be completed in less than 90 min, yields a broad range of activation degrees, and, since it involves no toxic reagents, may be used for preparing immobilized enzymes to be utilized in food manufacturing and processing. The immobilization ofStophylococcal Nuclease has been carried out by this method. The insolubilized derivatives are more active than the native enzyme in the hydrolysis of DNA. The thermal stability of nuclease derivatives is greater than that of the native enzyme. These derivatives remain active at 50°C, and the native enzyme, 39°C. The insolubilized nuclease is more stable against organic solvents such as, dimethylsulfoxide (DMSO) or tetrahydroduran (THF) than the native enzyme.     

Polysaccharide accumulation dynamics in Iris pseudacorus

It was established by studying carbohydrates of Iris pseudacorus during vegetative periods that the content of water-soluble polysaccharides in the rhizomes and roots is greatest during seed ripening; of pectinic substances, during budding. Glycomannan was isolated from seeds. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 216–217, May–June, 2006.