FOOD SCIENCE ›› 2020, Vol. 41 ›› Issue (2): 101-106.doi: 10.7506/spkx1002-6630-20181228-343

• Bioengineering • Previous Articles     Next Articles

Cryoprotective Effect of Acid-Cold Cross Stress on Lactobacillus fermentum

YANG Jie, GUO Jinfeng, LI Baokun, LU Shiling, WANG Qingling, DONG Juan, JIANG Caihong, JI Hua, WANG Tengbin   

  1. (Key Laboratory of Xinjiang Phytomedicine Resource and Utilization, Ministry of Education, Food College, Shihezi University, Shihezi 832003, China)
  • Online:2020-01-25 Published:2020-01-19

Abstract: This study aimed to explore the protective effect of acid-cold stress treatment on Lactobacillus fermentum strain ATm during freeze-drying. We determined the survival rate, lag time and acidification curve of freeze-dried bacteria cells which had been subjected to acid-cold cross stress. Furthermore, the activities of lactate dehydrogenase (LDH) and ATPase and cell membrane integrity were determined. The results showed that the acid-cold cross stress (pH 4.5 and 4 ℃) significantly improved the survival rate (reaching 87.19%, which was higher than that observed with either treatment alone) and acidification rate of the freeze-dried cells. In conclusion, acid-cold cross stress could improve the freeze-drying survival rate of L. fermentum ATm, protect its viability, increase intracellular enzyme activities and preserve cell membrane integrity.

Key words: cross-stress, freeze-drying, Lactobacillus fermentum, survival rate, viability preservation

CLC Number: