THE EFFICIENCY OF PAENIBACILLUS BACTERIA CULTIVATION ON NUTRIENT MEDIUM FROM ENZYMATIC HYDROLYSATE OF RICE HUSKS

Abstract

The full use of secondary raw materials from processing plants by biotechnological methods is economically feasible and promising for the biotechnological industry. The purpose of this study is developing technology for the utilization of rice husk to obtain nutrient medium for the cultivation of bacteria Paenibacillus, promising for the production of agricultural biological products, in particular, biological fertilizers and feed additives. The processing of rice husk by using chemical and biotechnological methods showed that optimized condition for the separation of fiber and mineral substances from rice husk is treating rice husk with sodium hydroxide with concentration 2.5% at 120 °C for 20 minutes. The possibility of obtaining simple sugars by enzymatic treatment of rice husk fiber with the enzyme preparation Accellerase 1500 for 24 hours at 55 °C was observed. Under these conditions, the enzymatic hydrolysate of rice husks contains 89% of reducing sugars of absolute dry matter, as well as amino acids and organic acids. It has been proved that the enzymatic hydrolysate of rice husk can be used as the main substrate for the cultivation of strains 560, 563, 567, 568, 572, 574, 17-2 bacteria P. mucilaginosus and 17-6 bacteria P. salinicaeni. Screening of bacteria Paenibacillus by specific growth rate, generation time, biomass yield, and also by the activity of extracellular enzymes, it was found that strain 560, which is recommended for further studies for developing technology of bioproducts for agricultural purposes.