DEGRADATION OF LEGUME PHYTATE IN SOIL USING FUNGAL PHYTASE

Abstract

Release of inorganic P was studied as a result of degradation of phytates during legume green manuring in soil. Aspergillus niger strain 419 was also inoculated for the production of phytase. Four sets of experiments were performed for maximum phytate degradation: (a) soil and legumes, (b) soil, legumes and phytase, (c) soil and phytase, (d) soil, legumes and A. niger strain 419. The soil in all of these samples was sterilized. Inorganic P was checked in each set after three different intervals of time (5 days, 8 days and 12 days) to estimate the degradation of phytates. The sample having A. niger strain 419 had highest content of free phosphorous after 5 days of incubation. The amount of free phosphorous reduced after 8 days in all samples except for the one containing soil, legumes and phytase. The amount of estimated inorganic P increased slightly in this sample. An increase in inorganic P was observed after 12 days in all samples except the first sample (soil and legumes). Estimated inorganic P further decreased in this sample. Same experiments were also performed with unsterilized soil. Inorganic P in all of the unsterilized samples decreased after 8 days and then increased after 12 days. The sample containing phytase, soil and legumes showed highest content of phosphorous after 12 days of interval, among unsterilized samples.