Determination of Optimized Growth Medium and Cryoprotective Additives to Enhance the Growth and Survival of Lactobacillus salivarius

Abstract

The beneficial effects of lactic acid bacteria (LAB) have been intensively investigated in recent decades with special focus on modulation of the host intestinal microbiota. Numerous discoveries of effective probiotics are driven by a significantly increasing demand for dietary supplements. Consequently, technological advances in the large-scale production and lyophilization are needed by probiotic-related industries for producing probiotic LAB for commercial use. Our study had a dual objective, to determine the optimum growth medium composition and to investigate appropriate cryoprotective additives (CPAs) for , and compare its responses with other species. The one-factor-at-a-time method and central composite design were applied to determine the optimal medium composition for cultivation. The following composition of the medium was established (per liter): 21.64 g maltose, 85 g yeast extract, 1.21 ml Tween 80, 6 g sodium acetate, 0.2 g MgSO₄∙7H₂O, 0.02 g MnSO₄∙H₂O, 1 g K₂HPO₄, 1.5 g KH₂PO₄, 0.01 g FeSO₄∙7H₂O, and 1 g sodium citrate. A cryoprotective additive combination comprising 10% (w/v) skim milk and 10% (w/v) sucrose supplemented with 2.5% (w/v) sodium glutamate was selected for, and its effectiveness was confirmed using culture-independent methods in the freeze-dried cells of the strains. In conclusion, the optimized medium enhanced the species-specific cultivation of. On the other hand, the cryoprotective effects of the selected CPA mixture may also be dependent on the bacterial strain. This study highlights the necessity for precise and advanced processing techniques for large-scale production of probiotics in the food and feed industries.

High-Fat Diet Affects Heavy Metal Accumulation and Toxicity to Mice Liver and Kidney Probably via Gut Microbiota

“…well known for its ability to modulate the microbiota in the host gastrointestinal tract, conferring beneficial effects in health (Holzapfel and Wood, 2014;Yeo et al, 2018). Our study proposed that Lactobacillus might also have function in heavy metal detoxification.…”

“…Lactobacillus abundance was positively correlated with fecal discharge of both As and Cd. With an estimated >200 species presently, Lactobacillus is well known for its ability to modulate the microbiota in the host gastrointestinal tract, conferring beneficial effects in health ( Holzapfel and Wood, 2014 ; Yeo et al, 2018 ). Our study proposed that Lactobacillus might also have function in heavy metal detoxification.…”

Anti-Inflammatory and Gut Microbiota Modulatory Effect of Lactobacillus rhamnosus Strain LDTM 7511 in a Dextran Sulfate Sodium-Induced Colitis Murine Model

“…Colonies of pathogenic indicators were collected, suspended in saline, diluted to OD 600 1.0, and mixed with the supernatant of L. rhamnosus strains in the same volume. After 5 min incubation, bacterial adenosine triphosphate (ATP) was detected based on luminescence (RLU) using a BacTiter-Glo TM Microbial Cell Viability Assay Kit (Promega, Madison, WI, USA) [35]. Sterilized fresh MRS medium was used as a negative control.…”

Rehydration before Application Improves Functional Properties of Lyophilized Lactiplantibacillus plantarum HAC03

“…However, during lyophilization, the microbial cells are exposed to stress conditions such as freezing, vacuumization, cryoprotectants, and low water activity that may cause sublethal cell damage. Factors that may play a role in bacterial cell survival include intrinsic strain resistance, initial cell concentration, cell density, growth conditions, growth phase at harvesting, and the (cryo-) protective agents used [ 4 , 5 , 6 , 7 ]. Moreover, the effectiveness of lyophilization is directly related to the type of applied cryoprotectant.…”

“…A combination of skim-milk (10%, w/v ) and sucrose (10%, w/v ), supplemented with sodium glutamate (2.5%, w/v ), was found to be successful for the cryoprotection of Ligilactobacillus (Lg.) salivarius during freeze-drying, and for yielding superior growth and survival [ 7 ]. Physiological deterioration will affect the viability and functionality of the culture and may be caused by cell shrinkage and the resulting disruption of cell integrity (by cell wall damage or as a result of membrane lipid oxidation), and by DNA, RNA and protein denaturation [ 4 , 9 ].…”