Mycota of distillery yeast sludge as source of single cell protein

Abstract

This study focused on the isolation, identification, and utilization of the mycota present in distillery yeast sludge as source of single cell protein. Seven fungal isolates were described and identified. These include three species of yeasts (Saccharomyces cerevisiae Meyen ex E.C. Hansen, Candida parapsilosis (Ashford) Langeron and Talice, and Candida guilliermondii (Castellani) Langeron et Guerra) and four species of molds (Aspergillus flavus Link, Aspergillus niger van Teigh, Aspergillus japonicus Saito var japonicus, and Rhizopus sp.). The ability of the fungal isolates to produce single cell protein was evaluated by determining the crude protein content (CPC) of the distillery yeast sludge after 14 days of solid state fermentation. Results revealed that inoculation of the seven taxa produced significantly higher percentage CPC of the distillery yeast sludge. Apparently, S. cerevisiae-treated distillery yeast sludge had the highest percentage CPC of 33.7% and the highest percentage increase in CPC of 34.3%, while Rhizopus sp.-treated distillery yeast sludge had the lowest of 21.8%. Thus, the present study indicates the great potential of the seven taxa as source of single cell protein using the distillery sludge as substrate.