乳链菌肽发酵的主要影响因子

采用中心组合实验设计方法（ＣｅｎｔｒａｌＣｏｍｐｏｓｉｔｅＤｅｓｉｇｎ），运用ＳＡＳ统计分析软件，得到了乳链菌肽发酵单位与主要影响因子之间的回归方程：ＹＩＵ＝１０８７．１７＋６２．８６Ｘ１＋７６．１８Ｘ２＋５５．４１Ｘ４－２３．３５Ｘ１１．６２Ｘ－１５．６７Ｘ２Ｘ４．根据方程及其岭岭分析结果，设计出含氮量较低的培养基ＳＹＳ３．同ＣＭ培养基相比，原料成本相差不大，但发酵单位提高了６４％．同ＭＲＳ培养基相比，虽然氮源含量降低了约５０％；发酵水平却相当，同时发酵液中残留的杂蛋白减少可以降低杂蛋白对Ｎｉｓｉｎ提取的干扰作用．

Effect of Major Factors of Fermentation Mediumon Nisin Production

By central composite design and the analysis using the SAS software, a quadraticregression equation on the relationship between nisin yield and its major influencing factorssuCh as soy peptone, yeast powder, sucrose and initial PH was formulated:un = 1087.17 62.86x1 76.18X2 55.41X4 - 23.35X2 11.62X-15.67X2X4A medium SYS3 with less nitrogen (soy peptome 6.25 g/L, yeast powder 5 g/L, sucrose 20 g/Land initial PH 7.0) was proposed according to the above equation and bridge analysis. Underthe same production cost, nisin production in the SYS3 medium was increased by 64% ascompared to that in the CM medium and was as same as that in MRS medium. The additionaladvantage is expected for nisin purtification due to the reduction of nitrogen cobment by 50%as compared to the MRS medium.