Comparative investigation on synergistic changes in enzyme activities during vermicomposting of cereal grain processing industry sludge employing three epigeic earthworm species.

Abstract

The management of cereal grain processing industry sludge through vermicomposting is an emerging prospect for researchers interested in the green economy. This work is designed to enumerate the enzymatic influence of three epigeic earthworm species - Eisenia fetida, Eudrilus eugeniae, and Perionyx excavatus on the industrial sludge. The vermicomposting experiment was conducted in plastic pots by blending the waste materials with 5% cow dung. The dynamics in activities of cellulase, amylase, invertase, phosphatase, protease, dehydrogenase, and urease were studied on 15days intervals till the harvesting period. The periodical observations confirmed that the enzyme activities (in terms of μg reducing sugar/g/hr) of cellulase (26.45-128.09) amylase (205.43-878.96), invertase (105.32-841.65), phosphatase (85.29-435.54), protease (64.21-359.47), dehydrogenase (111.17-587.72), and urease (94.16-476.71) was low in the first 15days of the vermicomposting experiment followed by a sharp increase in the next 45days accompanied by a steady decline until the harvesting is carried out. Emerging statistical tools such as principal component analysis were employed to study the synergistic deviations of the enzymes during the vermicomposting process. The results confirmed that the enzyme activity efficiently influences the bio-oxidation of industrial waste at an individual level as well as synergistic level thereby allowing the vermicompost to mature much before the appearance of any physical symptoms on the surface of the vermireactors.