1Department of Biology, School of Science, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand
2Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
3Vishnugupta Vishwavidyapeetam, Ashoke, Gokarna, 581326, India
Abstract
Twenty-seven coprophilous fungi, isolated from field-fed cow dung in an organic farm in Thailand, were identified using morphology and ITS barcode. A total of five genera viz. Aspergillus, Hamigera, Paecilomyces, Penicillium, and Talaromyces were identified with varying numbers and growth rates. These fungi were evaluated for their antibacterial properties against Gram-positive (Bacillus subtilis, Kocuria rhizophila, Staphylococcus aureus and St. epidermidis) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. Pe. javanicum NTD-SP2-01 and Talaromyces sp. NTD-SP5-48 exhibited activity against all bacteria when tested with agar plug diffusion method. Talaromyces sp. NTD-SP5-48 was particularly effective against Gram-negative bacteria. As. terreus NTD-NG1-05 displayed the highest activity against five bacterial strains, except Ps. aeruginosa. Notably, As. terreus NTD-NG1-05 and Talaromyces sp. NTD-SP5-48 demonstrated extended antibacterial activity in the agar disk diffusion method, with fermented broth (FB) showing superior inhibitory effects compared to mycelial extract (MY). Both isolates demonstrated significant antibacterial activity against B. Subtilis. Furthermore, all isolates exhibited significant antibacterial activity against B. subtilis, with a diffusion of 0.125 mg/disk. Only Talaromyces sp. NTD-SP5-48 (FB) displayed the highest inhibition activity against Ps. aeruginosa, with a diffusion of 1 mg/disk (100 mg/mL). In terms of enzyme activity, all isolates exhibited cellulase activity, with Talaromyces sp. showing the highest cellulase activity, followed by As. terreus. Laccase activity was only observed in the unidentified isolate NTD-SP5-34, while none of the isolates showed pectinase activity.
