Dongyan Shao, Linbo Yao, Muhammad shahid riaz, Jing Zhu,Junling Shi,Mingliang Jin, Qingsheng Huang, Hui Yang. Simulated Microgravity Affects Some Biological Characteristics of Lactobacillus Acidophilus

Simulated Microgravity Affects Some Biological Characteristics of Lactobacillus Acidophilus.

Dongyan Shao, Linbo Yao, Muhammad shahid riaz, Jing Zhu,Junling Shi,Mingliang Jin, Qingsheng Huang, Hui Yang.

Appl Microbiol Biotechnol

DOI 10.1007/s00253-016-8059-6

Abstract: The effects of weightlessness on enteric microor ganisms have been extensively studied, but have mainly been focused on pathogens. As a major component of the microbiome of the human intestinal tract, probiotics are important to keep the host healthy. Accordingly, understanding their changes under weightlessness conditions has substantial value. This study was carried out to investigate the characteristics of Lactobacillus acidophilus, a typical probiotic for humans, under simulated microgravity (SMG) conditions.The results revealed that SMG had no significant impact on the morphology of L. acidophilus, but markedly shortened its lagphase,enhanceditsgrowthrate,acidtoleranceabilityupto pH < 2.5, and the bile resistance at the bile concentration of <0.05%. SMG also decreased the sensitivity of L. acidophilus to cefalexin, sulfur gentamicin, and sodium penicillin. No obvious effect of SMG was observed on the adhesion ability of L. acidophilus to Caco-2 cells. Moreover, after SMG treatment, both the culture of L. acidophilus and its liquid phase exhibited higher antibacterial activity against S. typhimurium and S. aureus in a time-dependent manner. The SMG treatment alsoincreased the in vitro cholesterol-lowering ability of L. acidophilus by regulating the expression of the key cholesterol metabolism genes CYP7A1, ABCB11, LDLR, and HMGCR in the HepG2 cell line. Thus, the SMG treatment did have considerable influence on some biological activities and characteristics of L. acidophilus related to human health. These findings provided valuable information for understanding the influence of probiotics on human health under simulated microgravity conditions, at least.