Assessment of microbial roles in the bioconversion of paper mill sludge through vermicomposting

Abstract

Purpose Main thrust of the present study is to determine the role of microbes in changing the proportion and turnover of nutrients such as carbon and nitrogen during vermicomposting of paper mill sludge through the assessment of β-glucosidase and Leucine arylamidase activities. Methods The change in the ratio of Total Organic Carbon (TOC) and Total Kjeldahl Nitrogen (TKN) during sludge composting using paper mill sludge, cow dung, straw in the ratio of 5:4:1 have been determined alongside observing β-glucosidase and Leucine arylamidase activities in different phases (0th, 30th and 60th days) of vermicomposting. The present study also assessed the bacterial assemblages in order to predict their role as major producers of these enzymes as estimated by Vitek 2 system. Results A declining trend of C/N ratio was observed which exhibited significant negative and positive correlations with the activity of β-glucosidase and Leucine arylamidase respectively. Twenty-four strains were isolated under two genus Bacillus spp. and Lysinibacillus spp. which revealed differential sensitivity towards major carbon and nitrogen turnover mediating enzymes. Conclusion Change in the activities of carbon and nitrogen turnover enzymes due to microbial growth and proliferation are the mediator for the change in C/N ratio.

Assessment of qualitative enrichment of organic paper mill wastes through vermicomposting: humification factor and time of maturity

“…Using suitable species of earthworm, vermicomposting act as an effective biological process which converts complex organic wastes into a nutrient-enriched black gold or fertilizer known as vermicompost (Lalander et al., 2015; Yadav et al., 2011). During vermicomposting, an intricate relationship between earthworms and associated microbiota were found which help in bioconversion of toxic organic wastes into stable nutrient enriched organic products, popularly known as vermicompost (Bhat et al., 2013; Chakraborty, 2018; Ganguly and Chakraborty, 2018). Vermicompost has proved to be an efficient producer for plant growth regulators and nutrients in simple forms (Lim and Wu, 2016).…”

Antioxidant and Anticancer Roles of a Novel Strain ofBacillus anthracisIsolated from Vermicompost Prepared from Paper Mill Sludge

“…The temperature during the entire process of composting was maintained at 25°C with a moisture content of around 60% and pH (7.4-7.8) through the regular sprinkling of water. All the experiments were performed in triplicate [ 16 ].…”

“…200 μ l of the sample was added in nutrient broth (HIMEDIA) and kept at incubation for 48 h at 37°C. 10 μ l of samples was taken and further spread over minimal agar plate made up of nutrient agar (HIMEDIA) and kept at incubation for 24 hrs at 37°C for proper isolation of colonies [ 16 ].…”

“…Sequencing of DNA sample was performed using ABI PRISM Big Dye TM Terminator Cycle Sequencing Kits with AmpliTaq DNA polymerase (FS enzyme) (Applied Biosystems). Single-pass sequencing was performed using 27F/1492R primers and fluorescently label fragments were purified and subjected to electrophoresis in an ABI 370X1 sequencer (Applied Biosystems) [ 16 , 17 ].…”

Toward Sustainability in Rural Areas: Composting Palm Tree Residues in Rotating Bioreactors

“…Total nitrogen (TN, %) was analyzed based on the Total Kjeldahl-N (TKN) using a Foss-Kjeltec analyzer (Model: 8100, Denmark). The TKN analyzes the summation of organic nitrogen, nitrogen in the forms of ammonia (NH3-N) and ammonium (NH4-N), which are suitable microbial nitrogen forms during the active phase of composting [28,29]. Consequently, the carbon to nitrogen ratio (C/N) was calculated using the values of TOC and TN.…”