摘要
【目的】优化海洋源性细菌Bacillus licheniformis XJ-2(简称XJ-2菌株)产胞外多糖的培养基,并探究其抗氧化性。【方法】采用单因素法研究XJ-2菌株产胞外多糖培养基中碳源、氮源、pH及发酵时间等因素对胞外多糖产率的影响,采用经典的Fenton法及NADH-PMS-NBT系统研究该多糖的抗氧化性。【结果】优化后发酵条件为:蔗糖8%、硝酸钾2%、pH 7.5、发酵时间84h;胞外多糖产量高达17.752mg/mL;其对·OH和O-2·有较强的清除能力,IC50分别为2.0mg/mL(·OH)、0.06mg/mL(O-2·)。【结论】优化后发酵培养基明显提高了XJ-2菌株胞外多糖产量,且该多糖具有很高的抗氧化性,为胞外多糖的规模化生产以及开发新多糖类免疫调节剂提供了重要的参考资源。
Obj ective The aim of the study was to optimize the medium producing extracellular polysaccharide from Bacillus licheniformis XJ-2 and to investigate antioxidant properties of extra-cellular Polysaccharide.[Method]Single factor experiment was employed to explore the effects of carbon source,nitrogen source,pH and fermentation time on production of extracellular polysac-charide.The antioxidant characteristic of this polysaccharide was also investigated by the classical methods of Fenton and NADH-PMS-NBT.[Results]The optimal medium was shown as fol-lowed：sucrose 8% （w/v）,nitrate 2% （w/v）,pH 7. 5 and fermentation time 84 h.Under the conditions,the yield of extracellular polysaccharide was 17. 752 mg/mL.In addition,the polysac-charide had strong ability to clear ·OH and O-2 ·.The IC50 of extracellular polysaccharide to-ward ·OH and O-2 · were 2. 0 mg/mL and 0. 06 mg/mL,respectively.[Conclusion]The opti-mized medium significantly improved the yield of extracellular polysaccharide of Bacillus licheni-formis XJ-2.The extracellular polysaccharide exhibited high antioxidant activities in vitro.Our results could provide some important data for commercial polysaccharide production and potential application in immunomodulatory research.
出处
《四川农业大学学报》
CSCD
北大核心
2014年第2期165-171,共7页
Journal of Sichuan Agricultural University
基金
国家自然科学基金(No.31070047)
关键词
海洋微生物
地衣芽孢杆菌
细菌胞外多糖
优化
抗氧化性
marine microorganisms
Bacillus licheniformis
extracellular polysaccharides
opti-mization
antioxidant
