Chenchen Zhang1,2, Jingyu Lu1,2, Duo Yang1,2, Xia Chen1,2, Yujun Huang1,2, Ruixia Gu3,4. 1. College of Food Science and Engineering, Yangzhou University, 196 Huayang Xilu, Yangzhou, 225100, People's Republic of China. 2. Jiangsu Provincial Key Laboratory of Dairy Biotechnology and Safety Control, Yangzhou, People's Republic of China. 3. College of Food Science and Engineering, Yangzhou University, 196 Huayang Xilu, Yangzhou, 225100, People's Republic of China. guruixia1963@163.com. 4. Jiangsu Provincial Key Laboratory of Dairy Biotechnology and Safety Control, Yangzhou, People's Republic of China. guruixia1963@163.com.
Abstract
OBJECTIVE: To investigate the aerotolerance of Lactobacillus rhamnosus hsryfm 1301 and its influencing factors. RESULTS: The growth rate of L. rhamnosus hsryfm 1301 weakened noticeably when the concentration of supplemented H2O2 reached 1 mM, and only 2% of all L. rhamnosus hsryfm 1301 cells survived in MRS broth supplemented with 2 mM H2O2 for 1 h. After pretreatment with 0.5 mM H2O2, the surviving cells of L. rhamnosus hsryfm 1301 in the presence of 5 mM H2O2 for 1 h increased from 3.7 to 7.8 log CFU. Acid stress, osmotic stress, and heat stress at 46 °C also enhanced its aerotolerance, while heat stress at 50 °C reduced the tolerance of L. rhamnosus hsryfm 1301 to oxidative stress. Moreover, treatment with 0.5 mM H2O2 increased the heat stress tolerance of L. rhamnosus hsryfm 1301 by approximately 150-fold. CONCLUSIONS: Lactobacillus rhamnosus hsryfm 1301 possesses a stress-inducible defense system against oxidative stress, and the cross-adaptation to different stresses is a promising target to increase the stress tolerance of L. rhamnosus hsryfm 1301 during probiotic food and starter culture production.
OBJECTIVE: To investigate the aerotolerance of Lactobacillus rhamnosus hsryfm 1301 and its influencing factors. RESULTS: The growth rate of L. rhamnosus hsryfm 1301 weakened noticeably when the concentration of supplemented H2O2 reached 1 mM, and only 2% of all L. rhamnosus hsryfm 1301 cells survived in MRS broth supplemented with 2 mM H2O2 for 1 h. After pretreatment with 0.5 mM H2O2, the surviving cells of L. rhamnosus hsryfm 1301 in the presence of 5 mM H2O2 for 1 h increased from 3.7 to 7.8 log CFU. Acid stress, osmotic stress, and heat stress at 46 °C also enhanced its aerotolerance, while heat stress at 50 °C reduced the tolerance of L. rhamnosus hsryfm 1301 to oxidative stress. Moreover, treatment with 0.5 mM H2O2 increased the heat stress tolerance of L. rhamnosus hsryfm 1301 by approximately 150-fold. CONCLUSIONS:Lactobacillus rhamnosus hsryfm 1301 possesses a stress-inducible defense system against oxidative stress, and the cross-adaptation to different stresses is a promising target to increase the stress tolerance of L. rhamnosus hsryfm 1301 during probiotic food and starter culture production.