Website: https://vjfc.nifc.gov.vn/
Website: https://vjfc.nifc.gov.vn/
In this study, 36 yeast strains were isolated from fermented foods collected in different areas of Northern Vietnam. The screening process yielded 15/36 strains capable of good growth with Cell Dry Weight (CDW) ranging from 10-14 g/L, and 10/36 strains having the potential for single cell protein production with Total Protein Content (TPC) exceeding 57% (g/100 g cell dry weight) after 24 h of cultivation in YPD liquid medium. The yeast strain YPI-Y2 (with CDW reaching 14.03 g/L; TPC reaching 62.3%) was identified as closely related to the species Pichia kudriavzevii (99.77%) based on ITS rDNA sequence analysis and comparison. The nutritional and cultivation characteristics of the P. kudriavzevii YPI-Y2 strain, oriented towards cell biomass production and protein accumulation, were determined. The optimal cultivation temperature and initial medium pH condition for the growth and protein accumulation of the YPI-Y2 yeast strain were 30℃ and 6.5, respectively, while the suitable carbon source was identified as D-fructose. Simultaneously, this yeast strain maintained good growth and protein accumulation capability on inorganic nitrogen sources (except urea, with 35.62% of TPC). Under suitable cultivation and nutritional conditions, the CDW and TPC values reached 16.12 g/L and 66.62% (g/100 g CDW), respectively.
Single cell protein (SCP), Pichia kudriavzevii, yeast, fermented food, YPI-Y2
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