Phytochemicals and bioactivities of Artocarpus Lanceifolius roxb and Artocarpus Maingayi king

Abstract

Phytochemical studies on Artocarpus lanceifolius Roxb. and Artocarpus maingayi King have successfully isolated seven flavonoids and two plant sterols. Five compounds were successfully isolated from the stem bark of Artocarpus lanceifolius which were identified as 9,19-cyclolanost-24-en-3-acetate, cycloartobiloxanthone, artonol B, 7,8-(2,2-dimethylchromeno)-10-(2-hydroxyl-1- methylethyl)-2',4',5',5-tetrahydroxyflavone, and artonin E. Two flavans which were tentatively elucidated as 7,8-(2,2-dimethylchromano)-4',4,5-trihydroxy-2'- methoxyflavan and 8-(11-methyl-11-butenyl)-3,4',5,7-tetrahydroxy-2'- methoxyflavan have been isolated from the leaves of Artocarpus lanceifolius. Another two compounds were isolated from the leaves of Artocarpus maingayi which were identified as carpachromene, and ß-sitosterol. Structures of all compounds were elucidated spectroscopically by Nuclear Magnetic Resonance, Infrared, Ultraviolet Spectroscopies and Mass Spectrometry. Biological activities were carried out on the crude extracts and pure compounds. The antimicrobial testing on the crude extracts and pure compounds were carried out against the Gram-positive bacteria, Bacillus subtilis and Staphylococcus aureus and Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa. Most of the crude extracts and pure compounds showed significant antimicrobial activity. A pure compound, 7,8-(2, 2- Dimethylchromeno)-10-(2-hydroxyl-1-methylethyl)-2',4',5',5-tetrahydroxyflavone showed most significant antimicrobial activity compared to other isolated compounds and crude extracts with the minimum bactericidal concentration and minimum inhibition concentration value between 31.25 – 62.5 µg/mL. The antioxidant test on the crude extracts and pure compounds from both plant species showed potential free radical scavenger against 2,2-diphenyl-1-picrylhydrazyl. Artonin E exhibited the strongest antioxidant activity with 50% scavenging concentration at 46.9 µg/mL while the ethyl acetate crude extract from the stem bark of Artocarpus maingayi showed 50% scavenging concentration at 60.1 µg/mL.