Grace Omotine GODFREY

Digestate from cattle rumen is composed of microbial biomass, organic Matter and inorganic compounds derived from anaerobic digestion, can be used as an inorganic fertilizer or raw materials for biofertilizer production. This study was aimed at investigating the effect of temperature and time relationship towards reduction of bacteria in cattle rumen digestate and its resultant safety as biofertilizer. Cattle Rumen Digestate slurry (CRD) was obtained from National Centre for Energy and Environment in the University of Benin, Benin City, Edo State, Nigeria . The digestate was subjected to varying degrees of temp 28+2, 55, 60, 70
and 80 ℃ for a duration of 0,20,30, 40 and 60 min. The analysis carried out were for bacterial load using nutrient agar (NA) and Salmonella Shigella agar (SSA), physicochemical and heavy metal content. From the results, the lowest bacterial load of ( 0.5±0.00×10⁵cfu/ml) was recorded for exposure at 80 ⁰C after 60min and Salmonellae load recorded with (NO GROWTH) were from digestate exposure at 70 and 80 ⁰C after 40 and 60 mins respectively (for both temperatures) . Concentrations of nitrate, TK, TKN were highest at 60 ℃ and 80 ℃, TAN and TP were highest at 70 ℃ and 55℃ respectively, while 70 oC, heavy metals were lowest. This study study shows that digestate posses potential concerntration of nutrients and useful minerals which makes it suitable for agriculture land application.