The exopolysaccharides biosynthesis by Candida yeast depends on carbon sources

Abstract

a b s t r a c t 7 a r t i c l e i n f o 8 Available online xxxx 12 13 14 15 16 17Background: The exopolysaccharides (EPS) produced by yeast exhibit physico-chemical and rheological 18 properties, which are useful in the production of food and in the cosmetic and pharmaceutical industries as 19 well. The effect was investigated of selected carbon sources on the biosynthesis of EPS by Candida famata and 20 Candida guilliermondii strains originally isolated from kefirs. 21 Results: The biomass yields were dependent on carbon source (sucrose, maltose, lactose, glycerol, sorbitol) and 22 ranged from 4.13 to 7.15 g/L. The highest biomass yield was reported for C. guilliermondii after cultivation on 23 maltose. The maximum specific productivity of EPS during cultivation on maltose was 0.505 and 0.321 for 24 C. guilliermondii and C. famata, respectively. The highest EPS yield was found for C. guilliermondii strain. The 25 EPS produced under these conditions contained 65.4% and 61.5% carbohydrates, respectively. The specific 26 growth rate (μ) of C. famata in medium containing EPS as a sole carbon source was 0.0068 h -1 and 0.0138 h -1 27 for C. guilliermondii strain.28 Conclusions: The most preferred carbon source in the synthesis of EPS for both Candida strains was maltose, 29 wherein C. guilliermondii strain showed the higher yield of EPS biosynthesis. The carbon source affected the 30 chemical composition of the resulting EPS and the contribution of carbohydrate in the precipitated preparation 31 of polymers was higher during supplementation of maltose as compared to sucrose. It was also found that the 32 EPS can be a source of carbon for the producing strains. 33 34

Ameliorating the Metabolic Burden of the Co-expression of Secreted Fungal Cellulases in a High Lipid-Accumulating Yarrowia lipolytica Strain by Medium C/N Ratio and a Chemical Chaperone

“…The effects of simultaneous expression of multiple cellulases on the growth of Y. lipolytica was investigated by plotting the turbidity obtained from a Bioscreen C growth assay. Previously, the Bioscreen C instrument has been used to monitor microbial growth curve in terms of optical density of bacteria (Franden et al, 2009, 2013; Wang et al, 2014b) and yeast (Bom et al, 2001; Jung et al, 2015; Gientka et al, 2016). Y. lipolytica transformants expressing single cellulases were similar to their parent strain Po1g (EV) during the exponential growth phase and only show slight differences during the late growth phase (Figure 5).…”

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

“…Bullera, Candida, Cryptococcus, Debaryomyces, Lipomyces, Pichia, Pseudozyma, Rhodotorula, and Sporobolomyces (Rusinova-Videva et al 2010). The EPS produced by Candida yeast exhibited physicochemical and rheological properties which are useful in food, cosmetic, and pharmaceutical industries (Gientka et al 2016). Probiotic yeasts viz.…”

Production, medium optimization, and structural characterization of an extracellular polysaccharide produced byRhodotorula minuta ATCC 10658

“…Many research put forward hypotheses that carbon sources as a main precursor for EPS production had the highest effect on the polysaccharide's properties and supported the high quantity of polysaccharide. Various research studies were carried out to investigate the effect of the carbon and nitrogen sources on polysaccharides production (Gientka, Bzducha‐Wróbel, Stasiak‐Różańska, Bednarska, & Błażejak, 2016; Khani et al., 2016). Khani et al., 2016 (Khani et al., 2016) stated that EPS production was stimulated by the high content of glucose.…”

“…Khani et al., 2016 (Khani et al., 2016) stated that EPS production was stimulated by the high content of glucose. A study done by Gientka et al, 2016 (Gientka et al., 2016) revealed that, of all substrates used, carbon source significantly enhanced the yeast polysaccharide. Maalej et al., 2014 stated starch was discovered to be preferred over other carbon sources for EPS by Pseudomonas stutzeri AS22.…”