“Aislamiento e identificación de microorganismos con interés agroindustrial a partir de muestras de suelo de bosques primarios del cantón colta”

Abstract

The objective of this research is to isolate and identify microorganisms with agro-industrial interest focusing on the microbiological families of lactobacillus, saccharomyces, and acetobacter from soil samples of a primary forest. A selective culture medium for the three types of microorganisms was used to purify the species of interest. Colony forming units (CFU) were obtained, seeded by pour plate, then reseeded by streaking, followed by morphological isolation aided by microscopy. In addition, growth inhibitors were added for opportunistic microorganisms. The pH of the culture medium was between 4.8 and 5.5 in the absence of oxygen for lactic acid bacteria; On the other hand, yeasts were grown in a neutral pH with an abundant source of glucose in the absence of oxygen and their development was verified by fermentation when inoculated in citrus juice, where carbon dioxide (CO2) was also released, acetic acid bacteria were also seeded in a selective medium with an abundant source of glucose with a pH of 7 and in the presence of oxygen, then subjected to a citrus juice fermentation and tested for the release of hydrogen sulfide (H2S). For the statistical analysis, a T-Student test was performed for the pH values at the beginning and at the end of the fermentation process, for yeasts and acetic bacteria with values of 12.39 and 7.48 respectively, which were greater than 1.76. It is concluded that the results were positive; they were evaluated by biochemical tests where CO2 release was observed in the three cases and ethanol in the yeasts. It is recommended that good quality reagents and equipment be used.