K^(+)、Ca^(2+)对酿酒酵母的蔗糖乙醇发酵及理化特性的影响  

Effects of K^(+)and Ca^(2+)on sucrose ethanol fermentation and physicochemical properties of Saccharomyces cerevisiae

作　　者：袁瑞祥 伍时华[1,2] 龙秀锋 Yuan Rui-xiang;Wu Shi-hua;Long Xiu-feng(College of Biological and Chemical Engineering,Guangxi University of Science and Technology,Liuzhou,545006,China;Guangxi Key Laboratory of Green Processing of Sugar Resources,Liuzhou,545006,China)

机构地区：[1]广西科技大学生物与化学工程学院,广西柳州545006 [2]广西糖资源绿色加工重点实验室,广西柳州545006

出　　处：《广西糖业》2022年第4期25-33,共9页Guangxi Sugar Industry

基　　金：广西糖资源绿色加工重点实验室开放基金资助(GXTZY202003);2021年广西科技大学研究生教育创新计划项目(GKYC202126)。

摘　　要：以热酸预处理后的甘蔗糖蜜(总糖273.3±4.09 g/L)所测K^(+)(15.64 g/L)、Ca^(2+)(8.17 g/L)含量为依据,将其添加至250 g/L蔗糖乙醇发酵培养基中,研究K^(+)、Ca^(2+)对酿酒酵母GJ2008的蔗糖乙醇发酵及理化特性的影响。K^(+)、Ca^(2+)处理组与对照组相比,最大细胞生物量分别减少9.83%、18.45%,蔗糖水解及葡萄糖和果糖消耗减缓、蔗糖水解和耗糖时间延长,发酵至42 h残总糖量分别是对照组的2.16倍、2.79倍,乙醇生成量分别减少18.03%、23.81%。由扫描电镜图可以看出,K^(+)、Ca^(2+)处理组的酵母细胞表面出现絮状物,细胞呈堆积、粘连、凹陷等形态;傅里叶红外光谱分析发现高浓度K^(+)、Ca^(2+)可改变酵母细胞膜与细胞壁的几丁质、蛋白质、多糖羟基骨架等结构;K^(+)、Ca^(2+)处理组的酵母细胞为应对胁迫环境,处理6 h后的胞内海藻糖含量明显升高,与对照组相比分别增加了1.66倍、1.76倍。结果表明,K^(+)、Ca^(2+)对酵母的蔗糖乙醇发酵存在较强抑制作用,且Ca^(2+)(8.17 g/L)对酵母细胞的抑制作用强于K^(+)(15.64 g/L)。论文初步揭示了K^(+)、Ca^(2+)对酿酒酵母的蔗糖乙醇发酵过程及理化特性的影响,为进一步探究甘蔗糖蜜中金属离子对酿酒酵母的毒性机理,选育耐受性菌株,以开展利用高浓度甘蔗糖蜜实现高浓度乙醇发酵试验提供基础研究依据。Based on the contents of K^(+)(15.64 g/L)and Ca^(2+)(8.17 g/L)in sugarcane molasses(total sugar 273.3±4.09g/L)measured after pretreated with hot acid,they were added to ethanol fermentation medium(250 g/L sucrose)to study the effects of K^(+)and Ca^(2+)on ethanol fermentation process and physicochemi-cal properties of Saccharomyces cerevisiae GJ2008.Compared with the control group,the maximum cell biomass in K^(+)and Ca^(2+)treatment groups were reduced by 9.83%and 18.45%respectively.The rate of sucrose hydrolysis and glucose and fructose consumption were slowed down,and the time of sucrose hy-drolysis and sugar consumption were prolonged.After 42 h of fermentation,the total residual sugar con-tent was 2.16 times and 2.79 times that of the control group,respectively,and the ethanol production de-creased by 18.03%and 23.81%,respectively.In addition,it can be seen from scanning electron mi-croscopy,floc appeared on the surface of yeast cells in K^(+)and Ca^(2+)treatment groups,and the cells showed morphology of accumulation,adhesion and depression.FTIR analysis showed that high concentration of K^(+)and Ca^(2+)could change the structure of lipid,protein and polysaccharide hydroxyl skeleton of cell mem-brane and cell wall.Moreover,in order to cope with the stress environment,after 6 h of treatment the in-tracellular trehalose content of yeast cells in K^(+)and Ca^(2+)treatment groups increased significantly,which was 1.66 times and 1.76 times,respectively,compared with the control group.In summary,the results showed that K^(+)and Ca^(2+)had a strong inhibition effect on ethanol fermentation with sucrose by S.cere-visiae GJ2008,and the inhibition effect of Ca^(2+)(8.17 g/L)was stronger than that of K^(+)(15.64 g/L).This paper preliminarily reveals the effects of K^(+)and Ca^(2+)on ethanol fermentation process and physicochemi-cal properties of S.cerevisiae,which can provide a theoretical basis for further exploring the toxic mecha-nism of metal ions in sugarcane molasses on S.cerevisiae and breeding of tolerant stra

关 键 词：K^(+) CA^(2+) 酿酒酵母 乙醇发酵 理化性质 毒性机理 

分 类 号：S566.109[农业科学—作物学]