Isolation and characterization of a pichia anomala strain: A promising candidate for bioethanol production

Abstract

A yeast strain designated as Y-1 was isolated and characterized from wine yeast ("Jiuqu"). Based on the morphological and biochemical results, along with the rDNA internal transcribed spacer region (ITS), Y-1 was identified to be a Pichia anomala strain. Y-1 is an ethanol-tolerant strain, enduring ethanol concentrations of up to 14%. Y-1 growth medium conditions were optimized, results showing good growth in medium with pH ranges from 3.5-6.5, temperature ranges from 25-30 °C, and inoculums range of 8%-12%, while optimum growth conditions were reached at a temperature of 30 °C, pH 5.0, and inoculums of 10%. Furthermore, when the alkaline hydrolyzed Shatian pummelo peel solutions were inoculated with 10% Y-1 and fermented at 30 °C for 6 d, 4.7% pure ethanol (w/w) was produced, as evidenced by gas chromatography analysis. Our present study shows potential for the Y-1 strain to be a promising candidate for bioethanol production.