Evaluation of Some Native Bacteria Isolated From Composting Process

During the composing process, microorganisms involved in degradation of agricultural and municipal waste are of great importance. Therefore, identification of beneficial microorganisms could play an important role in improving the quality of the produced compost. Bacteria play an effective role in degradation of organic matter, So the objective of the present study was isolation and characterization of important bacterial strains during composting process. The bacteria were isolated from mature compost in Isfahan Compost manufacture using serial dilution method. The enzymatic activities (amylase, cellulose, xylanase and protease) of the isolates were measured by quantitative methods. Eleven isolates with enzyme activity were isolated and used for more detailed studies. The isolated bacterial strains showed a wide range of different enzymatic activities. Molecular identification of the selected strains was performed based on PCR amplification and sequencing of a 1500 bp fragment of bacterial 16SrDNA using PAF and PAR primers. Molecular studies revealed that 8 isolated bacterial strains were classified in the class of mesophilic bacteria, including Aneurinibacillus migulanus, Brevibacillus parabrevis, Brevibacillus agri, Pseudoxanthomonas suwonensis, Brevibacillus formosus, Bordetella petrii and Bacillus licheniformis, and 3 isolates were placed in the class of thermophilic bacteria including Geobacillus thermodenitrificans, Geobacillus sp., and Thermoactinomyces intermedius which are commonly exist in the composting process. Because of the municipal solid wastes are enriched cellulosic, starchy and protein compounds, these strains have high potential to degrade these wastes and accelerate the composting process.