title: Antioxidant, antimicrobial and tyrosinase inhibitory activities of xanthones isolated from Artocarpus obtusus F.M. Jarrett.
abstract: One of the most promising plants in biological screening test results of thirteen Artocarpus species was Artocarpus obtusus FM Jarrett and detailed phytochemical investigation of powdered dried bark of the plant has led to the isolation and identification of three xanthones; pyranocycloartobiloxanthone A (1), dihydroartoindonesianin C (2) and pyranocycloartobiloxanthone B (3). These compounds were screened for antioxidant, antimicrobial and tyrosinase inhibitory activities. Pyranocycloartobiloxanthone A (1) exhibited a strong free radical scavenger towards DPPH free radicals with IC50 value of 2 µg/mL with prominent discoloration observed in comparison with standard ascorbic acid, α-tocopherol and quercetin, The compound also exhibited antibacterial activity against methicillin resistant Staphylococcus aureus (ATCC3359) and Bacillus subtilis (clinically isolated) with inhibition zone of 20 and 12 mm, respectively. However the other two xanthones were found to be inactive. For the tyrosinase inhibitory activity, again compound (1) displayed strong activity comparable with the standard kojic acid.
authors.affiliation: Department of Chemistry, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
authors.forename: Najihah Mohd
authors.initials: NM
authors.lastname: Hashim
authors.forename: Mawardi
authors.initials: M
authors.lastname: Rahmani
authors.forename: Gwendoline Cheng Lian
authors.initials: GC
authors.lastname: Ee
authors.forename: Mohd Aspollah
authors.initials: MA
authors.lastname: Sukari
authors.forename: Maizatulakmal
authors.initials: M
authors.lastname: Yahayu
authors.forename: Muhamad Aizat Mohd
authors.initials: MA
authors.lastname: Amin
authors.forename: Abd Manaf
authors.initials: AM
authors.lastname: Ali
authors.forename: Rusea
authors.initials: R
authors.lastname: Go
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D031622:Artocarpus / Q000737:chemistry*; D001419:Bacteria / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D005658:Fungi / Q000187:drug effects; D020128:Inhibitory Concentration 50; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D044004:Xanthones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D004791:Enzyme Inhibitors; D010936:Plant Extracts; D044004:Xanthones; D014442:Monophenol Monooxygenase