Influence of metal addition on ethanol production with Pichia stipitis ATCC 58784
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Trace metals always act as cofactors or coenzymes in many cellular processes. Deficiency or excess of some metals will affect the fermentation of lignocellulosic hydrolysate. In order to make sure the deficient or excessive states of metals in culture medium, metal contents analysis was conducted in Pichia stipitis ATCC 58784 cells, synthetic medium, and diluted acid hydrolysate of rice straw. The results showed that Cu, Ni, and Co were deficient, and Al was a little excessive. So the influences of Cu2+, Al3+, Ni2+, and Co2+ additions on the growth and ethanol production of ATCC 58784 were further researched. Low concentration additions of Cu2+ and Al3+ (<0.24 mM and <0.23 mM, respectively) improved biomass growth of ATCC 58784 by 34 and 13%, respectively; however, higher concentrations decreased biomass growth. On the other hand, addition of Cu2+ (0.39 mM) did not affect volumetric ethanol production significantly (P = 0.05) and addition of Al3+ (0.38 mM) showed no influence on volumetric ethanol production (P = 0.68). Addition of 0.074 mM Co2+ inhibited biomass growth of ATCC 58784 by 13% and volumetric ethanol production by 10%. The biomass growth and volumetric ethanol production of ATCC 58784 was arrested by the addition of 0.33 mM of Ni2+ by 53 and 65%, respectively.
KeywordsTrace metal Ethanol production Pichia stipitis Xylose
- 5.Du Preez JC, Bosch WM, Prior BA (1986) The fermentation of hexose and pentose sugars by Candida shehatae and Pichia stipitis. Appl Microbiol Biotechnol 23:228–233Google Scholar
- 10.Stehlik-Tomas V, Zetić VG, Stanzer D, Grba S, Vahčić N (2004) Zinc, copper and manganese enrichment in yeast Saccharomyces cerevisiae. Food Technol Biotechnol 42:115–120Google Scholar
- 25.Zheng K, Pan JW, Ye L, Fu Y, Peng HZ, Wan BY, Gu Q, Bian HW, Han N, Wang JH, Kang B, Pan JH, Shao HH, Wang WZ, Zhu MY (2007) Programmed cell death-involved aluminum toxicity in yeast alleviated by antiapoptotic members with decreased calcium signals. Plant Physiol 143:38–49. doi: 10.1104/pp.106.082495 PubMedCrossRefGoogle Scholar