Abstract
Bio-conversion of cellulose containing raw materials into enriched with microbial protein and probiotics is one of the ways to increase the nutrition of fodder for livestock and poultry. Bio-conversion ofinitial substrates is a joint solid-phase fermentation by two groups of microorganisms. Saccharification ofraw materials is the first step of conversion performed by first group of bacteria from the Bacillus genus(producers of cellulolytic enzymes and antimicrobial substances). The second step is performed by special strains of yeast that produce proteins. Cellulose containing raw materials like wheat bran, sunflower meal and rice husk inoculated for 10days within 24-hours at 28-300 ° C temperature in bacterial broth culture. Effectiveness of fermentationbased on growth ability of 12 Bacillus genus strains on cellulose containing solid substrates by changingcontent of cellulose hydrolyzed by 80% H2SO4 and easily hydrolysable polysaccharides (hemicelluloses) hydrolyzed by 2% HCl.According to our research cellulose and hemicellulose in bran decreased to 2-6%, decrease in ricehusk is 7-10%, in sunflower meal is 5-9%. Three mixed cultures were constructed. Mix cultures basedon bacteria of the Bacillus genus and yeast Pichia guilliermondii increase cellulose destruction efficiencyby 2-3 times. The most active of them hydrolyzed 20-25% of cellulose on solid substrates.Prefabricated substrates were inoculated with yeast strains that capable to grow on initial substratesto 8 × 109 cfu / g during 3 days of cultivation, and preliminary bacterial conversion increases theirgrowth to 25%. The obtained results demonstrate the possibility of step-by-step degradation of the plantsubstrate by aerobic cellulolytic bacteria of the Bacillus genus and non-celluloseolytic yeast Pichia guilliermondii, which use sugar obtained by bacterial cellulose conversion.Key words: сellulose containing raw materials, solid-phase fermentation, Pichia guilliermondii, microbial protein.