摘要
【目的】研究盘针孢菌的发酵条件及其胞外多糖(EPS)抗氧化活性。【方法】分别研究碳源、氮源、生长因子、pH值和培养时间等条件对盘针孢菌多糖产量的影响作用,并通过测定其多糖的还原能力及对羟自由基(·OH)和1,1-二苯基苦基苯肼(DPPH)自由基的清除作用研究该多糖的抗氧化活性。【结果】盘针孢菌多糖发酵的最佳条件为20%的马铃薯浸汁,20g/L麦芽糖,5g/L(NH4)2SO4,0.01g/LL-胱氨酸,pH5.0,25℃下培养10d。在此条件下,多糖产量达到37.52mg/L,与在基础发酵培养基条件下相比,其多糖产量提高了84.10%。盘针孢菌多糖对·OH和DPPH自由基均有较好的清除作用,在多糖浓度为50mg/L时,对·OH的清除率达到50.81%;多糖浓度为20mg/L时,对DPPH自由基的清除率达到14.21%。【结论】发酵条件对盘针孢菌多糖代谢具有重要的调控作用,且该多糖具有明显的抗氧化活性。
[Objective] To study fermentative production of exopolysaccharide （EPS） from a Libertella sp. and to evaluate its antioxidant activity. [Methods] We studied the effect of carbon source, nitrogen source, growth factors, pH and culture time on the production of Libertella exopolysaccharide. By determining the reduction capability, the decoloration of 1,1-diphenyl-2-picrylhy- drazyl （DPPH） and the elimination of hydroxyl radicals, we evaluated the antioxidant activity of the Libertella exopolysaccharide. [Results] The optimum conditions for Libertella exopolysaccharide production were in a medium containing potato juice 20%, maltose 20 g/L, （NH4）2SO4 5 g/L and L-cystine 0.01 g/L and at pH 5.0 and 25℃ fermented for 10 d. Under this condition, exopolysaccharide concentration in the fermentation broth reached 37.52 mg/L, 84.10 % higher than that of the control. The scavenging effects of the Libertella exopolysaccharide on 1,1-diphenyl-2-picrylhydrazyl radical reached 14.21% with 20 mg/L exopolysaccharide, and the clearance rate of hydroxyl radicals reached 50.81% with 50 mg/L exopolysaccharide. [Conclusion] The ferment conditions have significant influence on the production of Libertella exopolysaccharide. The exopolysaccharide showed obvious antioxidant activity.
出处
《微生物学报》
CAS
CSCD
北大核心
2008年第10期1398-1402,共5页
Acta Microbiologica Sinica
基金
安徽省自然科学基金项目(050430502)
安徽省重点科研计划项目(07020303053)~~
关键词
盘针孢属
胞外多糖
抗氧化活性
Libertella
exopolysaccharide
antioxidative activity
