Efficient Citrus (Citrus unshiu) Byproduct Extract-Based Approach forLactobacillus sakeiWiKim31 Shelf-Life Extension

Abstract

Lactic acid bacteria produce various bioactive compounds widely used in human healthcare. However, studies on cryoprotective agents for the efficient storage of lactic acid bacteria after freeze-drying are still lacking. Here, we report the shelf-life extension effects of a highly efficient and eco-friendly cryoprotective agent and a cold adaptation method on Lactobacillus sakei WiKim31. Cold adaptation of L. sakei WiKim31 increased exopolysaccharide expression in response to abiotic stress. As a possible cryoprotective agent, the citrus byproduct (CP) contains a variety of sugars, amino acids, and cations, exhibiting high antioxidant activity. L. sakei WiKim31 powders formulated with CP or a mixture of soy powder (SP) and CP exhibited high cell viability at 58.3 and 76.3%, respectively, after 56 days of storage. These results indicate that CP can be efficiently used as a novel cryoprotective agent either alone or in combination with SP to improve the storage conditions of L. sakei WiKim31 and preserve it longer.

Sonochemical application reduces monosaccharide levels and improves cryoprotective effect of Jerusalem artichoke extract on Leuconostoc mesenteroides WiKim33 during freeze-drying

“…Previously, coffee residue extract and citrus byproduct as cryoprotective agents increased LAB viability, and supercooling pretreatment also increased the cell viability by over 10% [10] , [12] , [16] . In this study, immediately after freeze-drying of the Leu.…”

“…Cryoprotective agents have been investigated for prolonging the shelf life of bacteria. Carbohydrates such as disaccharides (sucrose, lactose, trehalose), polymers (starch, maltodextrin,), and sugar alcohol (sorbitol) are primarily considered as protective agents for LAB preservation [3] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] . Low-molecular-weight agents such as disaccharides, and sugar alcohol, prevent protein denaturation during FD process, forming hydrogen bonds with polar head groups of cellular membrane.…”

Eco-Friendly Approach for the Recovery of Lactic Acid by Complex Extraction

“…In prior reports, the LA concentration was kept very low or studied in a limited range. In the trials to investigate the effects of concentrations of TOA and LA, the LA molarity ranged from 0.1 to 1.5 M to be able to test the parameter over a wide range using titers from literature reports and to mimic an effective fermentation medium. − The pH values of the aqueous phases were in the ranges of pH 1.8–2.2. TOA concentration was chosen between 0.2 and 1.0 M (∼8.7–43.5% (v/v)) to keep the volume of vegetable oil in the organic phase higher than that of the amine extractant.…”

“…Lactic acid (2-hydroxypropanoic acid) can be manufactured by chemical and biological methods from carbon-based resources. , The former is not eco-friendly and uses relatively nonrenewable raw materials such as lactonitrile and hydrogen cyanide, which is also toxic . In addition, optically pure D-LA or L-LA isomers, which are preferred for industrial applications (e.g., polymers, foods, and pharmaceuticals), can be produced via microbial fermentation in biorefineries using low-cost feedstock or biomass .…”

“… 5 , 6 The former is not eco-friendly and uses relatively nonrenewable raw materials such as lactonitrile and hydrogen cyanide, which is also toxic. 7 In addition, optically pure D-LA or L-LA isomers, which are preferred for industrial applications (e.g., polymers, foods, and pharmaceuticals), can be produced via microbial fermentation in biorefineries using low-cost feedstock or biomass. 2 Biosynthesis of LA is carried out by bacteria, e.g., lactic acid bacteria (LAB, Lactobacillus sp.…”