Bioactive compounds from endophytic fungi from Hydnocarpus anthelminthicus Pierre ex.

Abstract

Endophytic fungi (68 isolates) were isolated from the twigs and leaves of the plant Hydnocarpus anthelminthicus Pierre ex. collected from the Central Botanical Garden (Pukae), Saraburi Province, Thailand. Based on the microscopic morphology and nucleotide sequencing of ITS regions of rDNA, endophytic fungal isolates HANT 7 and HANT 25 were identified as Phomopsis sp. In the present investigation, three compounds were isolated from MCz culture of the endophytic fungal isolate HANT 25 and one compound was isolated from the strain HANT 7. Fungal metabolites isolated were a new compound, 2-(8-methyl-9-oxa-bicyclo[4.2.1]nona-2,4-dien-7-yl)-6-oxo-tetrahydro-2H-pyran-3-yl-acetate, a new natural product, 5-hydroxy-6-(8-methyl-9-oxa-bicyclo[4.2.1]nona-2,4-dien-7-yl)-5,6-dihydropyran-2-one, and two known compounds, mycoepoxydiene and 2,5-furandimethanol. The isolated compounds 1, 2, 3 and 4 were evaluated for their biological activities. Compound 1 was found to exhibit strong anticancer activity against HuCCA-1, KB, HeLA,MDA-MB231, T47D, H69AR, HepG2, A549, S102, HL-60 and P388 cancer cell lines with IC₅₀ values of 0.30, 2.40, 2.10, 1.30, 2.00, 1.60, 2.25, 1.95, 2.80, 0.85 and 0.80 µg/mL, respectively, and also exhibited activity against Mycobacterium Tuberculosis with MIC value of 50 µg/mL. Compound 2 was found to exhibit strong anticancer activity against HepG2, A549 and S102 cancer cell lines with IC₅₀ values of 1.45, 1.70 and 0.87 µg/mL, respectively. Compound 3 was found inactive against HepG2, A549 and S102 cell lines. Compound 4 showed weak anticancer activity against HuCCA-1, MDA-MB231, T47D, HL-60 and P388 cancer cell lines.