酿酒酵母胞外多糖发酵工艺条件优化

为提高酿酒酵母产胞外多糖能力,了解酿酒酵母生长情况、代谢产物等特性,进一步扩大微生物多糖来源范围,对酿酒酵母发酵培养基中的碳源、氮源及各种金属离子对其胞外多糖的影响进行了研究,同时对碳源、氮源浓度配比进行了试验,还对发酵条件中pH、装液量、时间、接种量等组合进行了正交试验。确定发酵培养基最佳组合：葡萄糖5%、酵母浸粉0.5%、KH2PO40.1%。用此培养基,最佳发酵条件为：初始pH为4.5,装液量为50mL/250mL,接种量为5%,发酵时间为2d,在此条件下,胞外多糖产量可达到0.292mg/mL。

Fermentation Condition Optimization for Extrcellular Polysaccharides Production of Saccharomy cescerevisiae

In order to further increase the production of the exopolysaccharide(EPS)from Saccharomy cescerevisiae and to understanding of the properties of cell growth condition and metabolic products,to better expanding the source of microbial polysaccharides,in this research we study on selecting the carbon source type,the nitrogen source type and the organic salt,meanwhile to carbon source,nitrogen source proportion combination.Also to fermentation condition: pH,the attire liquid volume,the time,met the type and quantity and so on has been discussed by the orthogonal experiment.The optimum fermentation medium was determined as follows: 5% glucose,0.5% yeast extract powder and 0.1% KH2PO4,On the basis of optimal medium,the optimum fermentation conditions were obtained as follows: initial pH5.0,50mL liquid medium in a 250mL Erlenmeyer flask,5% of inoculation proportion and 2days of fermentation time,under the optimum conditions,yield of EPS could reach to 0.292mg/mL.