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121.
Immunoregulation Effect of Astragalus Polysaccharides 总被引:1,自引:0,他引:1
122.
Luiz H. Fasolin Rosiane L. Cunha 《International Journal of Food Science & Technology》2013,48(3):503-511
Soybean extract (SE), enriched in soy soluble polysaccharide (SSPS), was evaluated in three different conditions varying in extraction temperature and drying process: SE‐A ?80 °C, freeze‐dried, SE‐B ?80 °C, spray‐dried, SE‐C ?95 °C, spray‐dried. Spray‐dried SE presented lower moisture content, smaller and more uniform particles. In addition, zeta potential showed the same negative surface charge for all extracts showing the prevailing behaviour of SSPS. Moreover, all biopolymers were composed of three main molecular weight (Mw) fractions, but the Mw distribution was different between the three ingredients, reflecting their rheological behaviour in aqueous solution. Higher mean Mw led to enhanced apparent viscosity observed in neutral and acid pH for SE‐A, followed by ‐B and ‐C, respectively. The inverse behaviour was observed for intrinsic viscosity at neutral pH. However, SE‐C showed lower intrinsic viscosity at acid pH, which was attributed to protein–polysaccharide interaction presents in the solution. 相似文献
123.
Preparation,characterisation, antioxidant and antiglycation activities of the novel polysaccharides from the pileus of Dictyophora rubrovolvata
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Liping Sun Changjun Bao Weidan Chang Yongliang Zhuang 《International Journal of Food Science & Technology》2017,52(1):161-170
The polysaccharides from the pileus of Dictyophora rubrovolvata (DPP) were extracted by ultrasonic‐assisted extraction (UAE) and the operating parameters were optimised by orthogonal experiment. The polysaccharides were separated and purified by DEAE‐52 and Sephadex G‐100 column chromatography to obtain two fractions of DPP‐1s and DPP‐2s. The average of molecular weights, monosaccharide compositions, antioxidant and antiglycation activities of DPP‐1s and DPP‐2s were investigated. The results showed DPP‐1s and DPP‐2s had high inhibitory effects on oxidation and glycation, and DPP‐2s showed stronger bioactivity than DPP‐1s, which might be due to their differences in the molecular weight and uronic acid content. Furthermore, the UV and FTIR spectra were used to evaluate the characterisations of DPP‐2s, which demonstrated that DPP‐2s had no protein and nuclear acid with the pyranose ring structure. This study indicated that DPP‐2s could be used as a source of natural antioxidant and antiglycation components. 相似文献
124.
Zheng-qi Hao Zhen-jia Chen Ming-chang Chang Jun-long Meng Jing-yu Liu 《International Journal of Food Properties》2018,21(1):2283-2295
Rheological properties and gel characteristics of Sparassis crispa polysaccharides (SCPs) were investigated under various concentrations, temperature, pH, salt concentrations, and sucrose concentrations. SCP solutions behaved as shear thinning pseudoplastic fluids; apparent viscosity increased with concentrations but decreased with extreme conditions and was highest for 1% SCPs at 80 ℃ under neutral conditions; 5% SCPs solutions formed a hysteresis loop and exhibited thixotropic properties. By oscillatory measurements, SCPs were viscoelastic materials. 0.5% and 1% SCPs solutions exhibited viscous behavior at low frequency and enhanced elastic property with the oscillation frequency increased. With the concentration increased to 3% and 5%, the elastic property was predominant in solutions and exhibited gel-like behavior. SCPs gel textural properties and water holding capacity increased with concentration (to 20%) and decreased with salinity, extreme sucrose, and pH. 10% SCPs gels were optimized at 10% sucrose in neutral conditions. Thus, these results implied SCPs had the potential utilization as a new hydrocolloid source in food industries. 相似文献
125.
《国际聚合物材料杂志》2012,61(9):475-481
Derivatization of a natural polysaccharide, tamarind seed polysaccharide (TSP), was carried out. Both cationic and anionic derivatives of TSP were prepared, characterized, and their degree of substitution was determined. Films prepared using derivatives were evaluated for their swelling potential and bioadhesive strength. The carboxymethyl and sulfate derivatives were showed higher swelling index and required higher force of detachment compared to native gum thus, indicating that introduction of carboxymethyl, sulfate, and amine groups in TSP can increase the bioadhesive strength. The results suggested that anionic and cationic derivatives can be employed for formulation of bioadhesive drug delivery systems. 相似文献
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128.
阿魏菇多糖高产菌株筛选的离子束诱变和复合诱变对比研究 总被引:1,自引:0,他引:1
为筛选出阿魏菇菌丝体多糖高产菌株,本文进行了阿魏菇多糖高产菌株筛选的离子束诱变和复合诱变对比研究。尝试用打散的阿魏菇菌丝体为靶材,以离子束注入为诱变手段,通过营养缺陷型初筛和摇瓶发酵复筛,获得了2株阿魏菇多糖高产菌株PFPH-1和PFPH-2。其菌丝体多糖产量分别达到551.80mg,L和659.46mg/L,比出发菌株分别提高了46.55%和75.14%。再分别以PFPH.1和PFPH.2为出发菌株,用紫外线和氯化锂进行复合诱变处理,通过高通量初筛和摇瓶发酵复筛,结果发现,菌株1、9和10号比其出发菌株PFPH-1的多糖产量分别减少了27%、38%和37%;菌株17号比其出发菌株PFPH-2的多糖产量减少了28%。在本研究中,紫外线和氯化锂的复合诱变表现出了一定的负效应。 相似文献
129.
Tanaka M Yoshimura M Suto M Yokota A Asano K Sukara E Tomita F 《Journal of Bioscience and Bioengineering》2002,93(6):531-536
A highly potent allelopathic factor, lepidimoide, was initially extracted from mucilage of germinated cress seeds. Polysaccharide extracted from okra (Abelmoschus esculentum Moench) is considered to have a similar structure to lepidimoide as its repeating unit. We therefore initiated the screening of enzymes capable of degrading okra polysaccharide into lepidimoide from endophytes. We discovered an endophytic fungal strain AHU9748 isolated from Coleus galeatus, which produced an oligosaccharide having similar properties to lepidimoide on thin layer chromatography. The physico-chemical data from ESI-MS, NMR spectra and other analyses also showed the purified product to be identical to lepidimoide. The strain AHU9748 was identified as a fungus belonging to the coelomycetes, closely related to the genus Colletotrichum, based on morphological characteristics and sequence analysis of the 18S rDNA and ITS region. 相似文献
130.