山西大学学报(自然科学版)
山西大學學報(自然科學版)
산서대학학보(자연과학판)
JOURNAL OF SHANXI UNIVERSITY
2009年
3期
472-476
,共5页
王兴华%郑学瑞%邢会霞%任丽萍
王興華%鄭學瑞%邢會霞%任麗萍
왕흥화%정학서%형회하%임려평
嗜热链球菌%胞外多糖%生物合成%提取
嗜熱鏈毬菌%胞外多糖%生物閤成%提取
기열련구균%포외다당%생물합성%제취
Streptococcus thermophilus%EPS%synthesizing condition%extracting condition
以嗜热链球菌为材料,MRS培养基为基础培养基,研究了影响嗜热链球菌菌体生物量及胞外多糖生物合成的因素以及多糖提取的工艺条件.采用单因素法分析了碳源、氮源、初始pH值、温度、时间对嗜热链球菌生物量及胞外多糖生物合成的影响,结果表明嗜热链球菌生长的最佳条件为:葡萄糖20 g/L、大豆蛋白胨5 g/L、胰蛋白胨5 g/L、培养液初始pH 6.5、培养温度为37℃、培养时间24 h时,菌体生物量达5.00×10~(19)个/mL;嗜热链球菌产胞外多糖的最佳条件为:葡萄糖20 g/L、大豆蛋白胨5 g/L、胰蛋白胨5 g/L、培养温度为40℃时、培养时间27 h、培养液初始pH 6.5,胞外多糖产量达到为914.33 mg/L,胞外多糖产量相对于茵体的生长在时间上表现出滞后现象.多糖提取工艺的研究结果表明:以4倍体积的sevag液加入多糖溶液脱蛋白,用三倍体积90%的乙醇于4℃时沉淀12 h,多糖的提取效果最好.
以嗜熱鏈毬菌為材料,MRS培養基為基礎培養基,研究瞭影響嗜熱鏈毬菌菌體生物量及胞外多糖生物閤成的因素以及多糖提取的工藝條件.採用單因素法分析瞭碳源、氮源、初始pH值、溫度、時間對嗜熱鏈毬菌生物量及胞外多糖生物閤成的影響,結果錶明嗜熱鏈毬菌生長的最佳條件為:葡萄糖20 g/L、大豆蛋白胨5 g/L、胰蛋白胨5 g/L、培養液初始pH 6.5、培養溫度為37℃、培養時間24 h時,菌體生物量達5.00×10~(19)箇/mL;嗜熱鏈毬菌產胞外多糖的最佳條件為:葡萄糖20 g/L、大豆蛋白胨5 g/L、胰蛋白胨5 g/L、培養溫度為40℃時、培養時間27 h、培養液初始pH 6.5,胞外多糖產量達到為914.33 mg/L,胞外多糖產量相對于茵體的生長在時間上錶現齣滯後現象.多糖提取工藝的研究結果錶明:以4倍體積的sevag液加入多糖溶液脫蛋白,用三倍體積90%的乙醇于4℃時沉澱12 h,多糖的提取效果最好.
이기열련구균위재료,MRS배양기위기출배양기,연구료영향기열련구균균체생물량급포외다당생물합성적인소이급다당제취적공예조건.채용단인소법분석료탄원、담원、초시pH치、온도、시간대기열련구균생물량급포외다당생물합성적영향,결과표명기열련구균생장적최가조건위:포도당20 g/L、대두단백동5 g/L、이단백동5 g/L、배양액초시pH 6.5、배양온도위37℃、배양시간24 h시,균체생물량체5.00×10~(19)개/mL;기열련구균산포외다당적최가조건위:포도당20 g/L、대두단백동5 g/L、이단백동5 g/L、배양온도위40℃시、배양시간27 h、배양액초시pH 6.5,포외다당산량체도위914.33 mg/L,포외다당산량상대우인체적생장재시간상표현출체후현상.다당제취공예적연구결과표명:이4배체적적sevag액가입다당용액탈단백,용삼배체적90%적을순우4℃시침정12 h,다당적제취효과최호.
The influencing factors on biomass,exopolysaccharides(EPS) production and EPS extracting conditions were studied with Streptococcus thermophilus cultured on the MRS-based medium. The influencing factors of biomass and exopolysaccharides produced by Streptococcus thermophilus were studied by using single-factor analysis,including carbon,nitrogen,temperature,time and pH. The results showed that the biomass can reach to 5. 0×10~(19)/mL under the optimum conditions,i. e. glucose of 20 g/L,soybeans peptone of 5 g/L,pancreas peptone of 5 g/L, the initial pH of 6. 5 ,the culture temperature of 37 ℃ ,the culture time of 24 h. The optimum conditions of high yield of EPS(914. 33 mg/L) were as follows:glucose of 20 g/L, soybeans peptone of 5 g/L,pancreas peptone of 5 g/L,the initial pH of 6. 5,the culture temperature of 37 ℃ ,the culture time of 27 h. The extracting conditions of EPS were also examined. The results showed that the optimum EPS extracting conditions were:four times volume of sevag to remove protein,then precipitated with 3 times volume of 90% ethanol at 4 ℃ for 12 hours.