Abstract

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e challenges with eggshell wastes management are disposal cost, availability of dumpsite, flies and odour. However, this waste can be converted to useful materials. In this study, different gram of eggshell was substituted for proteins in nutrient broth to grow cellulase-producing bacteria. Crude and pretreated eggshell were added to 100ml of bacteriological media. Filter paper assay was used to determine cellulase activity produced by Pseudomonas aeruginosa and Bacillus cereus. From the results, highest cellulase activity of 28.80IU was observed from cellulase produced by Pseudomonas aeruginosa supplemented with 0.5g of the crude eggshell, assayed at 50oC for 60 minutes while the least activity of 2.50 IU was observed in cellulase produced by Bacillus cereus in 2.0g pretreated (15% HCl) eggshell supplemented medium at 40oC for 60 minutes. In the control (Nutrient broth), cellulase produced by Pseudomonas aeruginosa showed the highest activity of 42.20 IU at 50oC for 60 minutes while the least activity of 7.50IU was observed in cellulase produced by Bacillus cereus at 50oC for 60 minutes. Cellulase activity was low for 120 minutes at 50oC. This research findings show that eggshells contain protein which can be metabolized by Pseudomonas aeruginosa and Bacillus cereus. The enzyme cellulase acts best at an optimum temperature of 50oC for 60 minutes, it also shows that media supplemented with crude eggshell gave better yield than those of HCl pretreatment. Higher activities were observed in cellulase produced by Pseudomonas aeruginosa than those produced by Bacillus cereus.

Keywords: Eggshell waste, Waste management, Cellulase, Bacteria and Reaction time,