Seeds of Ornamental Tree Barringtonia asiatica as a Potential Source of Efficacious Antimicrobials

Abstract Microorganisms are the major cause of disease in human mucosal and deep tissue infections. Due to the development of resistance to existing drugs by microbes, discovering new antimicrobial agents is of paramount importance. Present study aimed at demonstrating growth inhibition of ATCC and clinical isolates of selected fungal and bacterial strains with a fraction (MPLCBA-3) isolated from crude methanolic extract (CME) with medium pressure liquid chromatography and CME of Barringtonia asiatica seed kernel. Both CME and MPLCBA-3 inhibited the growth of ATCC Candida strains studied except C. tropicalis. However, CME inhibited the growth of majority of clinical isolates of C. tropicalis. All clinical isolates of C. albicans and C. glabrata were inhibited by both fractions. Both CME and MPLCBA-3 were not active against most of the clinical isolates of C. parapsilosis at the given concentration. In the antibacterial study Staphylococcus aureus (ATCC) growth was inhibited (11 mm) by CME and Pseudomonas aeruginosa (ATCC) (14 mm) by MPLCBA-3 fraction. However, both fractions were not effective against Enterococcus faecalis, Escherichia coli, and their clinical isolates. MIC values of MPLCBA-3 reached 150, 200 and 250 ppm with C. albicans, C. parapsilosis, and C. glabrata respectively. Thus, CME and MPLCBA-3 fraction demonstrated potent antifungal activity at 33 and 50 times lower concentrations compared to positive control fluconazole but low antibacterial activity.