Title: Isolation And Characterization Of Mesophilic And Thermophilic Aerobic Bacteria From Compost
The isolation and characterization of mesophilic and thermophilic aerobic bacteria from home made compost was conducted in Gwagwalada, Nigeria and the composting was done for a period of 90 days. Initial temperature of the heap after mixing was 30°C which was higher than the environmental temperature (25 oC). Within a week (15 days), the pile temperature reached 35 °C and then increased to 50 °C on 45th day, as composting proceeded and finally dropped and stabilized at 28 °C (near to ambient) by the 90th day. The thermophilic and mesophilic bacteria isolated during composting were significantly different (P > 0.05), Bacillus cereus, Bacillus subtilis and Bacillus licheniformis had the highest number of occurrences, which represented 23.33 % each of the total isolates, followed by Serratia marcescens which represented 10 %. Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli represented 6.67 % each being the least isolates. The quantities of the cellulase enzyme produced showed that Bacillus subtilis had the highest cellulase and xylanase activity which give 26.18±0.10 and 24.10±0.12 Enzyme Unit (EU) respectively followed by Bacillus licheniformis which produced 25.10±0.20 EU and 22.50±0.20 EU for cellulase and xylanase respectively, Bacillus cereus with 22.14±0.11 EU and 20.02±0.02 EU for cellulase and xylanase respectively, Serratia marcescens with 20.09±0.14 EU and 18.20±0.18 EU for cellulase and xylanase respectively, Staphylococcus aureus with 19.22±0.21 EU and 17.40±0.17 EU for cellulase and xylanase respectively, Escherichia coli 18.50±0.50 EU and 16.33±0.25 EU for cellulase and xylanase respectively and Pseudomonas aeruginosa 16.20±0.21 EU and 14.11±0.08 EU for cellulase and xylanase respectively being the least value. There was no significant difference between the cellulase and xylanase activities produced by isolated thermophillic and mesophillic bacteria from compost.
Dr. Machunga-Mambula received her undergraduate degree in Microbiology from The Ahmadu Bello University, Zaria, Nigeria; Masters degree in Medical Microbiology from the University of Lagos, Nigeria and obtained her Ph.D. degree in Medical Microbiology from Manchester University, UK. She did her postdoctoral training at Boston University School of Medicine, USA in the Department of Infectious Diseases where she studied innate immune responses to fungal infections, with numerous scientific publications on Cryptococcus neoformans and Aspergillus fumigatus. Dr. M-Mambula became a faculty member at the Harvard Medical School in the Department of Radiation Oncology where she conducted numerous research projects on prostrate cancer and heat shock protein that resulted in several publications in international journals. It was during her period at the Harvard Medical School due to her interest in the control of infectious diseases in Nigeria that she developed the concept for the Nigerian Center for Disease Control (NCDC) and had it copyrighted at the Nigerian Copyright Commission.