Development of an L-Lysine Enriched Bran for Animal Nutrition via Submerged Fermentation by Corynebacterium glutamicum using Agroindustrial Substrates

Abstract

L-Lysine is an essential aminoacid added as supplement for animal feed. The aim of this work was to produce an L-Lysine enriched bran using Brazilian agroindustrial byproducts. Both the raw material costs and purification steps were minimized. Firstly, medium composition for the growth of Corynebacterium glutamicum ATCC 21799 was optimized targeting enhanced L-Lysine production - salt, vitamins and nitrogen sources concentrations were tested and selected. Next, UV mutant strains were generated and the best producers were used in formulated media using sugarcane molasses. It was reached a production of 9.3 g/L of L-Lysine with the optimized formulated media. This L-Lyisne rich broth was then impregnated and cyclically reimpregnated in pre-treated solid matrixes (sugarcane bagasse, citrus pulp, brewer spent grain, soybean husk and wheat bran). After processing, it was generated enriched brans with significant amounts of L-Lysine (13.8%, 7.0%, 8.9%, 5.9% and 8.4%, respectively), which has an interesting market potential for animal feed.