Phytochemical Investigation and Biological Activities of Moraceae Plants

Abstract

In this recent biological study of Moraceae plants, ethyl acetate and methanol extracts from Artocarpus chama and Streblus taxoides exhibited potent enzymatic antityrosinase activity. The ethyl acetate extracts of both plants were decreased the melanin content by increasing the antityrosinase activity on B16F1 melanoma cells. Moreover, these extracts sufficiently revealed antibacterial against gram-positive bacteria such as Staphylococcus aureus, Staphylococcus epidermidis, Cutibacterium acnes and methicillin-resistant S. aureus (MRSA). On the other hand, ethyl acetate and methanol extracts from S. taxoides were suppressed pigmentation producing on zebrafish assay. The chemical constituents from both plants were isolated by column chromatography. Eight compounds were isolated from ethyl acetate extract of A. chama which are three new compounds as 3'-farnesyl-apigenin; 3-(hydroxyprenyl) isoetin and 3-prenyl-5, 7, 2, 5'-tetrahydroxy-4-methoxyflavone; five known compounds as homoeriodictyol; isocycloartobiloxanthone; artocarpanone; naringenin and artocarpin. Six compounds were isolated from ethyl acetate and methanol extracts of S. taxoides are composed of one new compound as co-hydroxymoracin C; four known compounds as moracin M; moracin C; 3, 4, 3′, 5′-tetrahydroxybibenzyl; piceatannol and one mixture of B-sitosterol and stigmasterol. In determination of biological activities showed that, 8 isolated compounds as known as homoeriodictyol; 3'-farnesyl-apigenin; artocarpanone; o- hydroxymoracin C; moracin M; moracin C; 3, 4, 3, 5'-tetrahydroxybibenzyl and piceatannol exhibited enzymatic tyrosinase inhibitory activity. Further, all compounds were affected to intracellular antityrosinase activity on B16F1 melanoma by 2 different mechanisms as western blot confirmation. First, 4 compounds including artocarpanone; co-hydroxymoracin C; moracin M and moracin C inhibited enzymatic tyrosinase activity and down-regulated the expression of melanogenic proteins, resulting in decreasing melanin content. Second, one compound which is naringenin was not active as enzymatic tyrosinase inhibitory and up-regulated the expression of melanogenic proteins by increasing melanin content. Moreover, other 4 compounds which are homoeriodictyol; 3-farnesyl-apigenin; 3, 4, 3′, 5′-tetrahydroxybibenzyl and piceatannol inhibited enzymatic tyrosinase activity but increased melanin production by up-regulated the expression of melanogenic proteins. Additionally, isocycloartobiloxanthone, 3-hydroxyprenyl) isoetin 3-prenyl 5,725 tetrahydroxy-4-methoxyflavone, artocarpanone and artocarpin showed antibacterial effect against S. epidermidis with MIC value 4, 16, 16, 64 and 2 μg/mL, respectively, against S. aureus with MIC value 4, 16, 4, 64 and 2 μg/mL, respectively, against methicillin-resistant S. aureus (MRSA) with MIC value 16, 16, 4, 128 and 2 μg/mL, respectively and against C. acnes with MIC value 256, 128, 128, 32 and 8 μg/mL, respectively. While, co-hydroxymoracin C and moracin C showed antibacterial effect against S. epidermidis with MIC value 16 and 128 μg/mL, respectively, against S. aureus with MIC value 16 and 32 μg/mL, respectively and against MRSA with MIC value 16 and 32 μg/mL, respectively. Moreover, moracin M, 3, 4, 3′, 5′-tetrahydroxybibenzyl and piceatanol showed antibacterial effect against S. epidermidis with MIC value 64, 128 and 64 μg/mL, respectively and against MRSA with MIC value 64, 64 and 128 μg/mL respectively. The discovery of new compounds (3'-famesyl-apigenin; 3-(hydroxyprenyl) isoetin; 3- prenyl-5, 7, 2′, 5′-tetrahydroxy-4-methoxyflavone; a-hydroxymoracin C) that showed the potential of enzymatic antityrosinase activity and new compound (@-hydroxymoracin C) which showed the potential of antibacterial activity and decreased melanin content by reducing tyrosinase activity on B16F1 melanoma cells, will be useful to be the lead compound of new medicine development for treatment of hyperpigmentation and infectious diseases. This study is the first report for phytochemical investigation and biological activities of S. taxoides which was also for the new isolated compounds from A. chama and S. taxoides.