Identification and lipolytic activity of yeasts isolated from foods and wastes.

Abstract

Thirty-three yeasts were isolated from palm oil industrial wastes and traditional fermented foods in Thailand. Based on the analysis of the sequences of the D1/D2 region of the large subunit ribosomal RNA gene (LSU rDNA) and their phenotypic characteristics, they were identified as Pichia kudriavzevii (11 isolates), Candida ethanolica (1 isolate), Clavispora lusitaniae (2 isolates), Ogataea polymorpha (1 isolate), Hanseniaspora opuntiae (1 isolate), Lodderomyces elongisporus (1 isolate), Saccharomyces cerevisiae (2 isolates), C. tropicalis (5 isolates), Yarrowia lipolytica (2 isolates), Magnusiomyces ingens (1 isolate), and Magnusiomyces capitatus (3 isolates), Trichosporon insectorum (1 isolate), and Trichosporon asteroides (2 isolates). Seven strains, T. insectorum 4E-1D, M. capitatus 5E-1T and 5E-2D, T. asteroides 8E-1T and 8E-1D, and Y. lipolytica Fy-12 and Fy-13, showed high lipolytic activity ranged from 5.21 ± 0.09 to 45.68 ± 2.37 U/mL. Moreover, these seven strains exhibited good lipolytic activity after culturing in the medium containing palm oil (11.79 ± 0.67 to 28.19 ± 4.84 U/mL) and soy oil (9.14 ± 1.08 to 22.97 ± 0.69 U/mL) as lipase inducers. The result of this study suggests that the palm oil industrial wastes and Thai fermented foods could be promised as the invaluable sources of lipolytic yeasts.