Optimization of exopolysaccharide production by probiotic yeast Lipomyces starkeyi VIT-MN03 using response surface methodology and its applications

Abstract

In the present study, the cultural conditions for exopolysaccharide (EPS) production from probiotic yeast Lipomyces starkeyi VIT-MN03 were optimized using response surface methodology (RSM) to maximize the yield of EPS. Interactions among the various factors viz. sucrose concentration (1-3 g%), NaCl concentration (2-4 g%), pH (3-5), temperature (20-30°C), and incubation period (20-40 days) during EPS production were studied using Box-Behnken design (BBD). The EPS was purified and characterized using various instrumental analyses. The properties like adhesion, antioxidant, biosurfactant, cholesterol removal, and binding ability to mutagens were also tested for EPS produced. Sixfold increase in EPS production (4.87 g L −1) by L. starkeyi VIT-MN03 was noted under optimized condition. EPS showed a high viscosity (1.8 Pa S −1) and good shearthinning properties. Instrumental analysis showed that EPS was heteropolysaccharide composed of glucan, mannan, and rhamnan. Lipomyces starkeyi VIT-MN03 exhibited good self-adhesion (95%) and co-aggregation ability (93%). Adhesion efficiency for yeast inoculum containing 5.5 × 10 7 CFU mL −1 per 9.2 cm 2 of Caco-2 cell (colorectal adenocarcinoma) was noted. The probiotic EPS displayed strong antioxidant ability to scavenge hydroxyl radical and DPPH by 58% and 71% respectively. In addition, biosurfactant activity (86%) and cholesterol removal (90%) ability of probiotic EPS was also tested. EPS bound cells of L. starkeyi VIT-MN03 showed good binding ability to mutagens. These results support the effectiveness of using RSM for maximum EPS production. To the best of our knowledge, this is the first report on optimization of EPS production by probiotic yeast.

Physicochemical Characterization of an Exopolysaccharide Produced by Lipomyces sp. and Investigation of Rheological and Interfacial Behavior

“…Thirumal et al [7] demonstrated that the exopolysaccharide produced by L. starkeyi may contain mannose and galactose. Compared with the study of Mangala et al [17], it could be found that although exopolysaccharides were both yielded by L. starkeyi, their monosaccharide compositions were different. These differences were probably caused by genetic differences between different strains, and the different compositions of monosaccharides will lead to different structural and functional properties.…”

A Brief Review of Edible Coating Materials for the Microencapsulation of Probiotics

“…Additionally, it also helps in the treatment for irritable bowel syndrome (IBS), gastrointestinal dysbiosis, as for other intestinal disorders [2][3][4]. Most of the known probiotics are Generally Recognized As Safe (GRAS), including Lactobacillus and Bifidobacterium species, and certain yeast strains such as Saccharomyces boulardii, S. cerevisiae CNCM I-3856, and Lipomyces starkeyi VIT-MN03 [3][4][5][6]. Several mechanisms are proposed on how these microorganisms are beneficial to the host wellbeing.…”

Exploring biotechnological and functional characteristics of probiotic yeasts: A review

“…Meyerozyma caribacca 9C and 9D yeast strains expressed favorable properties of probiotics with 99.36% and 98.52% of auto aggregation respectively after 24 h of incubation time and these outcomes are near or higher than the reference strain [34] . Lipomyces starkeyi VIT-MNO3 revealed good probiotic assets with 95% of self-adhesion [35] . The auto aggregation capacity of Candida quercitresa CCMA 0560 isolated from indigenous fermented foods exhibited 95%±3.6% which was similar to reference strain Saccharomyces boulardii with 95.5%±0.1%.…”

“…The cell surfaces of yeast with high hydrophobicity afford both the greater aggregation capacity and also the adhesion capacity Debaryomyces hansenii in the cell surface hydrophobicity assay with 92.23±1.2% of hydrophobicity showed noticeable results when compared to control strain [24] . Lipomyces starkeyi VIT-MNO3 revealed good probiotic assets with 85% hydrophobicity [35] . About 68.53%±11.37% of cell surface hydrophobicity was reported by Kazachstenia turicansis whereas percentage of Saccharomyces cerevesiae JYC2619 was 6.10±1.5% [33] .…”