OBTENCIÓN Y CARACTERIZACIÓN DE ABONO ORGÁNICO LÍQUIDO A TRAVÉS DEL TRATAMIENTO DE EXCRETAS DEL GANADO VACUNO DE UN ESTABLO LECHERO USANDO UN CONSORCIO MICROBIANO ÁCIDO LÁCTICO

The increase of rainbow trout production in Peru generates a large amount of by-products which are not generally recycled, which generates greenhouse gases, eutrophication when they are thrown into the river and the appearance of pests when they are buried. The processes of hydrolysis and lactic acid fermentation allow to recover amino acids and nutrients, which can be used as a supplement for foliar fertilization of plants. The aim of this research was to develop a liquid fertilizer using rainbow trout by-products (FLVT), characterize it and evaluate the phytotoxicity. The total amino acid content was 3.2 g/100 g and protein content was 6.2 g/100 g. While the content of nitrogen, phosphorus and potassium were 12 040 mg/l, 1 189 mg/l, 5 540 mg/l, respectively. The liquid fertilizer did not contain E. coli or Salmonella sp. While the content of heavy metals such as lead, cadmium and chromium were lower than the maximum permissible limits according to the regulations for liquid fertilizers. In the phytotoxicity test on Lactuca sativa lettuce seeds, the concentrations of FLVT from 0.1% to 0.001% were free of phytotoxic substances and germination index values (IG) were greater than 80%.

Tratamiento de lodos residuales de una industria cervecera a través de fermentación homoláctica para la producción acelerada de abono orgánico

The purpose of this research was to evaluate the capability of lactic acid bacteria (LAB) to remove pathogens present in domestic wastewater, generated in the eco-touristic circuit Lomas de Lucumo (Lima, Peru). The pH decrease was used as an indicator of the elimination of fecal coliform bacteria in the treated water. Experiments included 36 treatments, which consisted of different mixtures of sugar molasses and a lactic acid bacteria inoculum (B-Lac) in proportions of 0, 1, 3, 5, 7 and 10% (v/v) and wastewater in a fixed proportion of 200 ml, under a completely randomized design (CRD) with factorial arrangement 6x6. The pH values on the third day were evaluated using an Analysis of Variance (ANOVA) followed by Tukey´s range test for mean differences (p < 0.05). The different treatments were analyzed in a first stage for 9 days, after which the best three were selected for a second evaluation: T16 (3% molasses and 5% B-Lac), T22 (5% molasses and 5% B-Lac) and T33 (10% molasses and 3% B-Lac); results show that the interaction effect between the two variables is significant. Finally, treatment T16 was selected as the most efficient, reaching a pH of 4.08 in a short time (3 days) that assured the complete removal of fecal coliform bacteria (9.65x10⁵ MPN/100 ml) in the wastewater.

Monascus purpureus is produced in Asia and used as a food dye and for medicinal purposes. In the present study, the radial growth of quinoa flour-based culture media was evaluated on the tenth day after cultivation with different sources of carbon (glucose, fructose and molasses), nitrogen (monosodium glutamate, fermented fish and fish hydrolysate) and sodium chloride in two percentages (0.5% and 1%) at different pH (5, 6 and 7). The highest value obtained was 72.59 mm with a radial growth rate of 3.629 mm/day, corresponding to the effect of 0.5% (w/v) sodium chloride at pH 6, and the lowest value was 42.05 mm with a radial growth rate of 2.10 mm/day, due to the effect of 0.5% (w/v) monosodium glutamate at pH 7. From this investigation, it was deduced that different sources of carbon, nitrogen and sodium chloride have effects on the development of M. purpureus and that factors such as pH and supplement concentration did not cause changes in the morphology of the colonies.

Alpa-biol es un bioproducto desarrollado por el Departamento de Biología de la Universidad Nacional Agraria La Molina vía fermentación homoláctica a partir de heces de alpaca en condiciones de laboratorio, cuyo proceso de elaboración podría verse afectado por factores ambientales adversos. El objetivo del estudio fue evaluar la eficiencia de la fermentación homoláctica en condiciones alto andinas, replicando la elaboración del Alpa-biol a mediana escala en la Sociedad Agrícola de Interés Social (SAIS) Pachacútec (Junín). Para ello se emplearon heces de alpaca, lactosuero, melaza y el consorcio microbiano benéfico “B-Lac” en proporción 40:40:15:5, respectivamente, monitoreándose diariamente el pH hasta alcanzar el valor más bajo. Se realizaron análisis físico[1]químicos y microbiológicos al inicio y después de 1 año a fin de determinar su estabilidad en el tiempo. Los resultados fueron comparados con los parámetros del Alpa-biol original, con 2 grupos de biofermentos (abonos líquidos acelerados y bioles de digestión anaerobia) y estándares de calidad. Se obtuvo en un periodo corto de 10 días un bioproducto carente de enteropatógenos, con caracteres organolépticos deseables, adecuado contenido nutricional y estable en el tiempo, similar a los reportes del estudio original y al grupo de abonos acelerados. Sin embargo, existen diferencias notables con respecto a los bioles debido a la naturaleza fermentativa, siendo su uso indicado en sistemas de producción agrícola como bioenmienda.