Abstract

Characterization of products from sawdust degradation using selected microbial culture isolated from it was carried out. A composite sawdust waste sample was collected from MCC timber market in Calabar. The sample was diluted using serial dilution method and inoculated on Nutrient agar and Sabauraud dextrose agar using pour plate technique and incubated at 370C and 270C respectively. Five bacteria species and 3 species of fungi were identified which included Bacillus sp, Serracia mercescens, Micrococcus sp, Pseudomonas aeruginosa, Streptococcus sp, Aspergillus niger, Rhizopus sp and Penicillumsp. The bacteria and fungi species were individually and in combination inoculated into sterile sawdust containing sterile water. These were kept at 270C for 21 days. Protein, glucose contents and chemical components in the degraded sawdust samples were determined using GC-MS chromatography. It was observed that Aspergillus niger degradation had protein content 7.87g/l, Serracia mercescens and Aspergillus niger 6.56g/l, and Serracia mercescens 5.75g/l. These organisms used lignocellulolytic enzymes and similar enzymes in the degradation process. In the case of glucose, the combined degradation produced 2.24g/l, Aspergillus niger 2.05g/l and Serracia mercescens 1.94g/l. It was also observed that sawdust inoculated with Serratia marcescens produced 14 compounds while the combined species of Aspergillus niger and Serratia marcescens produced only 12 compounds. The following compounds Methylene cyclo propane carboxylic acid, Glycine N-Cyclopropylcarbonyl-methyl ester, acetic acid, propanoic acid, benzaldehyde, thiophene, tetrahydro, furfural and propanoic acid 2,2-Dimethyl-2-ethylhexyl ester were detected from  the combination of Serratia marcescens and Aspergillus niger  though in different concentrations. The percent concentrations of the compounds from Serratia marcescens range from n-Hexadecanoic acid 3.59 to  Methylene cyclo propane carboxylic acid with 11.56 while Serratia marcescens and Aspergillus niger range from Butanoic acid, 4-chloro 3.59 to  Benzaldehyde with 11.56. Microbial degradation of sawdust produced economically important products and therefore can contribute to the economy of this country at  the same time reduce pollution caused by it which is a novel.

Key words: Sawdust, biodegradation, bioactive, extracts, microbial culture, lignocellulosic.