Abstract
The goal of this work was to evaluate the effect of zinc sulphate heptahydrate on growth rate and β-carotene production and to obtain zinc-enriched biomass using selected yeast strain Rhodotorula glutinis CCY 020-002-033. The batch cultivation was performed on synthetic basal medium supplemented with various concentrations of ZnSO4·7H20 (0.025%, 0.035%, and 0.050%), in shake flasks and aerobic conditions, at 300C, for five days. Total zinc accumulated in yeast cells after fermentation period was performed using ICP-OES. The identification and yield of β–carotene were investigated by chromatographic analysis (HPLC). It was found that the amount of total zinc accumulated in yeast cells depends mainly on the zinc concentration in the culture medium. The highest zinc content of 7.030 mg/g dry biomass was obtained at optimal concentration of 0.025%, with an incorporation efficiency of 87%. High concentration of 0.050% was not tolerated by yeast. Zinc salt in concentration of 0.025%, acted as stimulant for volumetric β–carotene but not improve yeast growth biomass. β-Carotene maximum content in this strain’s cell mass accounted 7.1 mg/L, when the dry cell biomass (1.89 g/L) was smaller than control (1.94 g/L), although there was no significant difference observed in final dry cell biomass versus control. The obtained results showed that when ZnSO4·7H20 concentration was increased up to 0.050% a decrease in yeast growth rate, β–carotene production and zinc accumulation was observed.
Highlights
Yeasts are able to bioaccumulate essential mineral salts from aqueous solutions through mechanisms as production of metalloproteins, mineralization and capture of metals into vacuoles (Eide, 1997)
The goal of this work was to evaluate the effect of zinc sulphate heptahydrate on growth rate and β-carotene production and to obtain zinc-enriched biomass using selected yeast strain Rhodotorula glutinis Collection of Yeast (CCY) 020-002-033
This study looked at the effect of ZnSO4·7H20 added in the culture media on Rhodotorula glutinis CCY 020-002-033 strain growth rate, β-carotene production and zinc accumulation in cells
Summary
Yeasts are able to bioaccumulate essential mineral salts from aqueous solutions through mechanisms as production of metalloproteins, mineralization and capture of metals into vacuoles (Eide, 1997). Saccharomyces strains were investigated for their ability to accumulate high concentrations of Cu, Zn and Mn salts to obtain ions enriched biomass (Barbulescu et al, 2009; Šillerová et al, 2012; Azad et al, 2014) and the “pink yeast” Rhodotorula glutinis to demonstrate the stimulatory effect of Ba, Fe, Mg, Ca, Zn, Co divalent cations on growth rate and volumetric production of carotenoids (Bhosale et al, 2001; Buzzini et al, 2005; Martínez et al, 2006; Dai et al, 2007). Very little published information is available on the production of zinc enriched biomass and β-carotene by R. glutinis CCY 020-002-033
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of microbiology, biotechnology and food sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
