Isolation and screening of potential lignocellulolytic microbes from Phra Nakhon Si Ayutthaya Province

Phra Nakhon Si Ayutthaya Province is an important area for rice cultivation in Thailand. However, large amounts of rice straw generated at harvest time are often burnt in the fields, causing environmental degradation and air pollution. To address this, rice straw composting by degrading microorganisms has been identified as an effective alternative for sustainable waste management, with potential applications in environmental biotechnology. For this study, 28 microorganism samples were collected from various sources in Phra Nakhon Si Ayutthaya Province, including a corrugated paper manufacturer, plant-cultivated soil, compost from dung, black soldier flies, and vermicompost. Lignocellulolytic microorganisms were screened for cellulase, xylanase, and manganese peroxidase production on agar plates and broth media using commercial and rice straw substrates. The lignocellulolytic activities were compared among the isolated and non-pathogenic microorganisms. A microbial consortium with high potential to degrade rice straw was identified, consisting of two thermophilic bacteria, Bacillus licheniformis BKT1 and BOT4, two mesophilic actinomycetes, Streptomyces ardesiacus AQ4 and An6, two thermophilic actinomycetes, Streptomyces thermoalcalitolerans APT3 and Streptomyces thermoviolaceus subsp. thermoviolaceus AQT2, and two fungi, Penicillium sp. Fh11 and Aspergillus sp. Fj6. This microbial consortium induced rapid composting of rice straw, thereby supporting sustainable agricultural waste management and reducing PM25 air pollution.