摘要
利用紫外线对保加利亚乳杆菌ZLB进行诱变处理60s(菌株致死率大约为99%),中间培养后用青霉素筛选。处理液涂布培养后,选取生长缓慢或不长的40株接种于RSM(ReconstitutedSkimmedMilk)培养基中,随后选取凝固的12株做12℃时贮藏,最终得到产酸较慢的突变株ZU05。在42℃时,ZU05在RSM培养基中产酸量与ZLB一样。但是发酵脱脂乳在12℃贮藏时,ZU05产酸量与ZLB的产酸量有显著性的差异(p<0.01),其发生后酸化时间推迟了4d。同时,ZU05对链霉素的敏感性不同于ZLB且能稳定遗传。
L delbrueckii subsp, bulgaricus ZLB was irradiated for 60s with UV （lethal effect was about 99%）, and mid-cultivated and counterselected with penicillin. After the spread cultivation, forty strains that grew slowly were cultured in RSM （Reconstituted Skimmed Milk）. Twelve strains which coagulated RSM were stored at 12℃, and a mutant （ZU05）, with the slowest lactic acid producing rate, was selected for further use. ZU05 produced the same amount of lactic acid as the parent strain at 42℃. However, during the storage at 12℃. It is significantly different between ZU05 and ZLB in their lactic acid producing capability （p 〈 0.01）, and the postaeidification of ZU05 was delayed four days. Also, the sensitivity to streptomycin of ZU05 was different with ZLB, and ZU05 could be genetically stable.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2006年第6期109-112,共4页
Food Science
基金
北京市教委项目(GJSY10090401)
关键词
后酸化
保加利亚乳杆菌
紫外诱变
postacidification
Lactobacillus bulgaricus
UV mutagenesis
