高产2-苯乙醇酵母菌株的筛选及培养基优化

摘要

2 - phenylethanol is an aromatic alcohol with a rose - like odor. It is a very important fragrance used in the cosmetic and tobacco industries and is also largely used in food industries. More and more people like 2 - phenythanol from microorganism than synthetic from chemicals. In one - phase fermentation, the yield of 2 - phenylethanol by single strain of yeasts are 3. 6g/L and 3. 8g/L in China and abroad respectively. Two strains were selected during the initial screen: a strain of Saccharomyces cerevisiae TYQ which could produce 1.6886g/L 2 - phenylethanol and another strain of Geotrichum candidum GS10A which could produce 1.0025g/L 2 - phenylethanol. Medium of the TYQ was optimized by the single factor test and orthogonal test. The optimized medium contains glucose 80g/L, L - phenylalanine 35g/L, yeast extract powder l0g/L, peptone l0g/L Grown under the condition of 10% (v/v)inoculation, 28℃ and 120i/min for 36h, the yeast TYQ yielded 2 - phenylethanol of 4.4025g/L%2-苯乙醇是一种具有玫瑰香气的芳香醇,作为重要香味添加剂之一广泛应用在食品、化妆品及烟草行业中.国内外崇尚利用微生物发酵法生产天然2-苯乙醇.目前国内外报道的单相单菌株产量分别达到3.6g/L和3.8g/L.本文从9株酵母及9株白地霉中筛选出一株2-苯乙醇产量达1.6886g/L的酿酒酵母菌株TYQ和另一株产量达1.0025g/L的白地霉菌株GS10A.经单因素及正交试验对酵母TYQ培养基优化,获得最佳培养基组成为:葡萄糖80g/L,L-苯丙氨酸35g/L,酵母粉10g/L,蛋白胨10g/L.该菌株在接种量10％(v/v)、28℃、120r/min条件下发酵36h的2-苯乙醇产量为4.4025g/L.