食品科学 ›› 2009, Vol. 30 ›› Issue (3 ): 192-196.doi: 10.7506/spkx1002-6630-200903043

• 生物工程 • 上一篇    下一篇

干酪乳杆菌基因组改组菌株耐酸性表征

王玉华1,2,李 岩1,裴晓林1,王秀娟2,冯 雁1,*   

  1. 1.吉林大学 分子酶学工程教育部重点实验室 2.吉林农业大学 食品科学与工程学院
  • 收稿日期:2007-10-26 出版日期:2009-02-01 发布日期:2010-12-29
  • 通讯作者: 冯 雁1,* E-mail:yfeng@mail.jlu.edu.cn
  • 基金资助:

    吉林省农业科技发展计划项目(200302-02)

Characterization of Acid Tolerance of Genome-shuffled Strain of Lactobacillus casei rhamnosus

WANG Yu-hua1,2,LI Yan1,PEI Xiao-lin1,WANG Xiu-juan2,FENG Yan1,*   

  1. (1.Key Laboratory for Molecular Enzymology and Engineering, Ministry of Education, Jilin University, Changchun 130023,
    China;2.College of Food Science and Engineering, Jilin Agricultural University, Changchun 130118, China)
  • Received:2007-10-26 Online:2009-02-01 Published:2010-12-29
  • Contact: FENG Yan1,* E-mail:yfeng@mail.jlu.edu.cn

摘要:

本实验对干酪乳杆菌基因组改组菌株的耐酸性进行了研究,结果表明,冷冻( - 80℃)和临界pH 值(pH3.2)对干酪乳杆菌基因组改组菌株影响不显著,HCl 和游离乳酸对该菌株生长有一定影响,游离乳酸影响更大。在pH5.0 条件下发酵60h,干酪乳杆菌改组菌株获得的菌体干重为6.34g/L,乳酸产量为87.6g/L,比原始菌株耐酸性有显著提高。

关键词: 干酪乳杆菌, 耐酸性

Abstract:

The acid tolerance of four strains of genome-shuffled Lactobacillus casei rhamnosus (Lc-F31, Lc-F32, Lc-F33 and Lc-F34) was characterized. The results showed after 3 passagings the viable numbers of these strains of genome-shuffled Lactobacillus casei which were spreaded on YE agar plate at pH 3.8 and 4.0 are similar. The acid tolerance of strain Lc-F34 in MRS liquidmedium at pH 3.2 is more significant compared with the original strain. The strain Lc-F31, Lc-F32, Lc-F33 and Lc- F34 still have good genetic stability after 20 passaging. Free lactic acid has more significant effect on growth of Lc-F34 than HCl in the shake-flask fermentation culture (YE medium) at differernt pHs. The batch fermentation of strain Lc-F34 was carried out in 5-L fermenter containing 3-L YE medium at the fixed pH 5.0 throughout the process. It was found that after 60-h fermentation, the produced lactate concentration of strain Lc-F34 is up to 87.6 g/L with the cell dry weight of 6.34 g/L.

Key words: Labtobacillus casei rhamnosus, acid tolerance

中图分类号: