Fraserin A, a new chromanone isolated from the stem bark of Calophyllum fraseri M.R.Hend. & Wyatt-Sm.

A new chromanone, Fraserin A (1) was successfully isolated from the stem bark extract of Calophyllum fraseri, together with calolongic acid, isocalolongic acid, and apetalic acid. The characterisation and structural elucidation of the isolated compounds were established by extensive spectroscopic data analysis and comparison with literature data. The antimicrobial activity was tested using the broth microdilution assay, whereas activity on microbial biofilms were determined using a semi-quantitative static biofilm. Compound (1) exhibited significant activity against Candida albicans and Streptococcus mutans, with MIC value of 62.5 µg/mL. At 500 µg/mL, it showed antibiofilm activity, inhibiting biofilm formation against C. albicans (30.95%) and S. mutans (85.15%). These findings highlight Fraserin A as a biologically active chromanone with dual antimicrobial and biofilm-modulating properties.