Microbial protein production from waste of sugar cane processing (bagasse pith)

Abstract

A study was undertaken of microbial biomass production using hydrolyzed pith bagasse acid as a growth medium. Hydrolysis was carried out using diluted (6%v/v) sulfuric acid in a reaction time of four hours. The equipment used operated at boiling conditions with atmospheric pressure reflux, and with a liquid/solid relation of 30. The concentration of sugars in the hydrolyzed solution was carried out by a rotational evaporator. The Candida utilis (ATCC 9256) and Saccharomyces cerevisiae (ATCC 26603) yeasts were cultivated in the hydrolyzed concentrate at a pH of 5.00, 30 °C and 200 rpm. The greatest production of biomass was 4.90 ± 0,03 kg/m3 in S. cerevisiae and 9.45 ± 0,01 kg/m3 in C. utilis. The yield of biomass was 1.19 ± 0,012 kg/kg in S. cerevisiae and 1.86 ± 0,040 kg/kg in C. utilis. The specific rate of growth was 0.0141 ± 0,0001 and 0.0544 ± 0,0001 h-1 for S. cerevisiae and C. utilis, respectively. The biotechnological process utilized is an important fundamental alternative for the industrial usage of pith bagasse from sugar cane through the production of a protein concentrate for animal feeds.