Affiliation:
1. College of Life Science, Northeast Forestry University , No. 26, Hexing St., Harbin 150040 , China
2. Key Laboratory of Forest Food Resources Utilization of Heilongjiang Province , No. 26, Hexing St., Harbin 150040 , China
3. State Key Laboratory of Food Science and Technology, Nanchang University , No. 999, Xuefu St., Nanchang 330047 , China
Abstract
Abstract
Aims
This study aimed to investigate the changes of cell membrane structure and function of Issatchenkia terricola under citric acid by performing physiological analysis.
Methods and results
The membrane integrity, surface hydrophobicity, structure, fluidity, apoptosis, and fatty acid methyl esters composition of I. terricola WJL-G4 cells were determined by propidium iodide staining, microbial adhesion to hydrocarbon test, transmission electron microscopy analysis, fluorescence anisotropy, flow cytometry, and gas chromatography-mass, respectively. The results showed that with the increasing of citric acid concentrations, the cell vitality, membrane integrity, and fluidity of I. terricola reduced; meanwhile, apoptosis rate, membrane permeable, hydrophobicity, and ergosterol contents augmented significantly. Compared to control, the activities of Na+, K+-ATPase, and Ca2+, Mg2+-ATPase increased by 3.73-fold and 6.70-fold, respectively, when citric acid concentration increased to 20 g l−1. The cells cracked and their cytoplasm effused when the citric acid concentration reached 80 g l−1.
Conclusions
I. terricola could successfully adjust its membrane structure and function below 60 g l−1 of citric acid. However, for citric acid concentrations above 80 g l−1, its structure and function were dramatically changed, which might result in reduced functionality.
Funder
Heilongjiang Tongsheng Food Technology Co., Ltd.
Publisher
Oxford University Press (OUP)