Endophytic fungi from Lagenandra toxicaria and Kaempferia rotunda were isolated and evaluated for their antimicrobial and anthelmintic activities. Based on the morphological and ribosomal large subunit rDNA gene (D1D2) sequence, LTRH2 and LTRO1 isolated from L. toxicaria were identified as Aspergillus tamarii and Aspergillus niger, respectively. The KMPRO2 isolated from K. rotunda was identified as Aspergillus flavus. Among the endophytic fungi isolated from L. toxicaria rhizome, the LTRH2, LTRO1, and LTRH1 showed conspicuous growth inhibition against all the Gram-positive bacteria tested. In vitro nematicidal activity of these endophytic extracts showed significant mortality to Haemonchus contortus first instar larva. Among the isolates of L. toxicaria, LTRH2 induced mortality to H. contortus larva with an LC50 of 2.03 mg/ml and LTRO1 with an LC50 of 3.67 mg/ml. The extracts of KMPRO2 and KMPRH1 also showed similar results with an LC50 of 2.63 and 2.44 mg/ml, respectively. high-performance liquid chromatography mediated polyphenol profiling of these extracts revealed the presence of many phenolic molecules common in both the crude rhizome extract and the endophyte extracts of the respective plants. These fungal extracts are, therefore, recommended for further study as a novel source of phytochemicals with good biological activity.
Key words: K. rotunda, L. toxicaria, Endophytes, Haemonchus, Nematicidal, Antibacterial
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