Chromium (II), Cobalt (II) and Tungesten (VI) mixture increments the nutritive value of Candida utilis (Torula) as a promising mineral-enriched fodder and food

Single cell protein such as Torula represents a promising solution for the future food shortage crisis. Cr3+, Sr2+, Ni2+, Co2+, W6+, Mo6+, Li+, Sn2+, B+ and Se4+ at (10, 50, 100, 150, 200 µM) were screened for their effect on Candida utilis AUMC10703 (Torula) biomass, All metal ions stimulated biomass production except Co 2+. Se6+ increased biomass by 137.5 % at 200 µM, Cr3+ and Li+ increased biomass by 145% and 130% at 150 µM respectively, Sr2+ increased it by 114 % at 100 µM. W6+, Mo6+ and Ni2+ increased it by 112%, 117 % and 114% at 10 µM respectively. B+ and Sn2+ increased biomass by 137% and 117% at 50 µM, respectively. Co2+, Cr3+and W6+ mixture (Co2+ 100µM, Cr3+ 150µM, W 6+ 50µM) increased amino acids, protein, DNA, RNA and organic acids content of C. utilis biomass by 184%, 141.5%,148.5%,145%, and 329%, respectively. Only carbohydrate content decreased to 23%. Raffinose, glucose and maltose production was induced. All essential amino acids increased except cysteine and glycine. SDS –PAGE analysis of C. utilis biomass revealed that the mixture induced two new intracellular protein production with size 75 and 72 KDa and increased the expression of an intracellular protein with size 25 KDa. Cr3+ decreased organic acids production, but Co+2 increased their production. (Co2+ 100µM, W 6+ 50µM) mixture increased organic acids by 157% and induced citric, pyruvic and malic acid production in the culture media.