Impeding Bacillus spore germination in vitro and in milk by soy glycinin during long cold storage

The Journal of General and Applied Microbiology

Mahmoud Z. Sitohy²  Samir A. Mahgoub¹  Ali O. Osman² 

[1] Microbiology Department, Faculty of Agriculture, Zagazig University;Biochemistry Department, Faculty of Agriculture, Zagazig University

关键词: Bacillus;    glycinin;    milk storage;    spore germination;    spore leakage;   

DOI  :  10.2323/jgam.62.52

学科分类：微生物学和免疫学

来源: Applied Microbiology, Molecular and Cellulrar Biosciences Research Foundation

【 摘 要 】

This paper presents a study of the magnitude and mechanism of impeding the emergent spore germination of Bacillus subtilis (non-hemolytic strain) and Bacillus licheniformis (hemolytic strain) under the action of soybean glycinin and its basic subunit (BS). Incubating B. licheniformis spores with 100 μg/ml of glycinin or BS at 35°C for 24 h totally prevented the hemolytic activity associated with the emergent vegetative cells on blood agar during 3–5 days of incubation at 35°C in contrast to the control. Glycinin and BS (100 μg/ml) also resulted in the leakage of 70 and 73% of the initially germinating spore contents of A260 absorbing materials of the two bacterial species after 2 h of incubation at 35°C, respectively. Increasing the concentration of glycinin and BS up to 400 μg/ml increased the germinating spore leakage to 83 and 88%, respectively. Spore germination in Muller Hinton Broth containing glycinin and BS (100 μg/ml) was practically nil after 4 days of incubation at 35°C. Supplementing milk preheated at 80°C/5 min with both glycinin and BS kept the final vegetative cell counts down to about 30 and 20% of the corresponding control, respectively, after 50 days of storage at 4°C. Both light, and transmission electron, microscopy images revealed significant morphological and structural distorting changes in BS-treated spores of B. licheniformis.

【 授权许可】

Unknown