多粘芽孢杆菌204产生的高粘性多糖性质的研究

STUDIES ON THE HIGH-VISCOSITY POLYSACCHARIDE PRODUCED BY BACILLUS POLYMYXA 204

多粘芽孢杆菌(Bacillus polymyxa)204能在萄葡糖培养基中,产生具有高粘性的胞外多糖,发酵48—72h产率为12g/L。在浓度为0.6％,1.0％和1.5％时,它的粘度分别为327,3715和44650厘泊、该菌产生的胞外多糖是一种酸性多糖,它由葡萄糖、甘露糖和半乳糖组成;其克分子比为5:5:2;糖醛酸含量为5.5％;其中1％水溶液具有加热熔化、冷却后凝固的类琼脂性质。本文还讨论了浓度、pH、加热温度和时间,以及添加盐类对比多糖的影响。毒性试验证明,此多糖是无毒的,LD50>10g/kg。

A bacterial strain producing a high-viscosity,agar-like polysaccharide was isolated from soil and identified as Bacillus polymyxa 204. Twelve grams of the polysaccharide per liter were produced by the strain after 48-72 h.The viscosity of the polysaccharide solution at 0.6o％,1.0％ and 1.5％ was about 327 cp,3715 cp and 44650 cp respectively. The polysaccharide was found to be acidic,and to be composed of glucose, mannose and galactose in an approximate molar ratio 5: 5: 2. The content of uronic acid is 5.5％. The polysaccharides form a gel when their acueous suspension (more than 1％) is heated to 100℃ and then cooled to room temperature.The effects of polysaccharide concentration pH, heating temperature and time,and the addition of salt on viscosity of 204 polysaccharide were studied. No acute toxicity was found on feeding the polysaccharide to mice. LD50>10g kg.