title: Flavonoids from the leaves and heartwoods of Artocarpus lowii King and their bioactivities.
abstract: A new dihydrochalcone, 2',4'-dihydroxy-3,4-(2″,2″-dimethylchromeno)-3'-prenyldihydrochalcone (1) together with 4-hydroxyonchocarpin (2), isobavachalcone (3), 4',5-dihydroxy-6,7-(2,2-dimethylpyrano)-2'-methoxy-8-γ,γ-dimethylallyflavone (4), artocarpin (5) and cycloheterophyllin (6) were successfully isolated from the leaves and heartwoods of Artocarpus lowii King (Moraceae). The structures of these compounds were fully characterised using spectroscopic methods and by direct comparison with published data. These compounds were tested for their antioxidant and tyrosinase inhibitory activities. Compound (1) displayed moderate antioxidant activity towards DPPH and tyrosinase inhibitory activities with SC50value of 223.8 μM and IC50value of 722.5 μM, respectively. Among the isolated compounds, cycloheterophyllin (6) showed the most potential antioxidant activity with SC50value of 320.0 and 102.8 μM for ABTS and DPPH radicals scavenging activities, respectively, and also exhibited highest FRAP equivalent value of 4.7 ± 0.09 mM. Compound (6) showed tyrosinase inhibitory activity with the IC50value of 104.6 μM.
authors: a Faculty of Science, Department of Chemistry , Universiti Teknologi Malaysia , Johor Bahru , Malaysia.
authors: Siti Awanis
authors: SA
authors: Abdullah
authors: a Faculty of Science, Department of Chemistry , Universiti Teknologi Malaysia , Johor Bahru , Malaysia.
authors: Shajarahtunnur
authors: S
authors: Jamil
authors: a Faculty of Science, Department of Chemistry , Universiti Teknologi Malaysia , Johor Bahru , Malaysia.
authors: Norazah
authors: N
authors: Basar
authors: a Faculty of Science, Department of Chemistry , Universiti Teknologi Malaysia , Johor Bahru , Malaysia.
authors: Siti Mariam
authors: SM
authors: Abdul Lathiff
authors: a Faculty of Science, Department of Chemistry , Universiti Teknologi Malaysia , Johor Bahru , Malaysia.
authors: Norzafneza
authors: N
authors: Mohd Arriffin
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D031622:Artocarpus / Q000737:chemistry*; D052160:Benzothiazoles / Q000737:chemistry; D001713:Biphenyl Compounds; D047188:Chalcones; D002855:Chromatography, Thin Layer; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D037241:Mannose-Binding Lectins; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors; D010851:Picrates; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry*; D037121:Plant Lectins; D013056:Spectrophotometry, Ultraviolet; D013451:Sulfonic Acids / Q000737:chemistry; D014934:Wood / Q000737:chemistry*
chemical_list: C000618486:2',4'-dihydroxy-3,4-(2',2'-dimethylchromeno)-3'-prenyldihydrochalcone; D000975:Antioxidants; D052160:Benzothiazoles; D001713:Biphenyl Compounds; D047188:Chalcones; D004791:Enzyme Inhibitors; D005419:Flavonoids; D016166:Free Radical Scavengers; D037241:Mannose-Binding Lectins; D010851:Picrates; D010936:Plant Extracts; D037121:Plant Lectins; D013451:Sulfonic Acids; C090683:artocarpin lectin; C468754:isobavachalcone; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; C107099:cycloheterophyllin; C004931:1,1-diphenyl-2-picrylhydrazyl; D014442:Monophenol Monooxygenase; C015812:dihydrochalcone
keywords: Artocarpus lowii; antioxidant; dihydrochalcone; flavonoids; tyrosinase inhibitory activity