Isolation, in vitro evaluation and construction of Versatile Microbial Consortia

Abstract

In this study, we constructed versatile microbial consortia (VMC) with potential applications in organic waste management. After the sample and isolation procedure, the purified isolates were evaluated for their enzymatic potential, such as cellulose, xylan, petroleum, and proteins -hydrolysis. Selected isolates were screened for other traits, such as phosphate solubilization, nitrogen fixation and antimicrobial activity. Finally, the isolates were grouped into consortia according to their compatibility. The microorganisms selected for each consortium were identified by partial analysis of the 16S rRNA (bacteria) and the ITS region of the 18S RNA gene (fungi). Two microbial consortia were obtained and named VMC1 and VMC2. These two consortia are characterized by several activities of agricultural and environmental interest, such as the degradation of recalcitrant and polluting organic compounds, nitrogen fixation, IAA production phosphate solubilization and antimicrobial activity. Molecular identification of the microorganisms forming the two consortia allowed us to identify two species of actinomycetes (Streptomyces sp. BM1B and Streptomyces sp. BM2B), one species of Actinobacteria (Gordonia amicalis strain BFPx) and three fungal species (Aspergillus luppii strain 3NR, Aspergillus terreus strain BVkn and Penicillium sp. BM3). The term "Versatile Microbial Consortia"is a term that we proposed in this study to establish a methodology for building multifunctional microbial groups for the better valorization of organic waste.