Agro-industrial and soil residues represent promising raw materials for biotechnological processes, contributing to a reduction in associated costs. These residues additionally serve as reservoirs of microorganisms, facilitating the bioprospecting of enzyme-producing bacteria of biotechnological significance. Soil environments, in particular, exhibit remarkable microbial biodiversity, with numerous microorganisms remaining uncharacterized. Proteases are extensively employed enzymes, commonly incorporated into detergents and widely utilized across the food, pharmaceutical, and textile sectors. Amylases are similarly indispensable in the food industry. Consequently, the present investigation focused on bioprospecting for bacteria demonstrating potential for the production of these enzymes from two distinct sample origins: oily residue generated from soybean processing, supplied by the COAMO cooperative (Dourados-MS unit), and soil collected from the Várzeas do Rio Ivinhema State Park. To this end, two differential culture media were formulated, each augmented with specific substrates to induce the respective production of protease and amylase enzymes. Following the isolation of pure colonies, a qualitative assessment of enzymatic activity was performed. The Enzyme Index (EI) was determined via the cup-plate method, calculated as the ratio of the degradation halo diameter to the colony diameter. Isolates presenting an EI exceeding 2.0 mm were designated as robust enzyme producers. Subsequently, morphotintorial classification was executed utilizing the Gram staining method on the colonies identified as strong enzyme producers. The outcomes revealed the successful isolation of one bacterium exhibiting protease production potential and two bacteria with amylase production potential from the agro-industrial waste sample. Conversely, the soil sample yielded one bacterium with amylase production potential and five with protease production potential. All isolated strains in this study were characterized as Gram-positive rods and tested positive for catalase Productions.
Souza et al. (Mon,) studied this question.