ABSTRACT
The mango (Mangifera) is the most important commercial fruit in Asia and is popular worldwide. Because of uncertainty in its origin and biogeography, the study of Mangifera could be of value in elucidating its current genetic diversity and geographical distribution. We report here two new species of compressed leaves of Mangifera (Anacardiaceae) from upper Oligocene-lower Miocene lacustrine sediments in the Li Basin, northern Thailand. Leaf form and venation characters of fossil and extant leaves are presented with detailed marginal venation patterns that were found to be important in assigning the fossil leaves to Mangifera paleoindica and M. paleocaloneura. These two fossil species of Mangifera and the present occurrence of basal species of Mangifera in Thailand suggest that northern Thailand could be an area with a long history of evolution and diversification of Mangifera, particularly M. indica.
ABSTRACT
Ten new 1,3,5-trioxygenated xanthones, nigrolineaxanthones J-S (1-10), one new quinone derivative, nigrolineaquinone A (11), and one new isoflavone-like compound, nigrolineaisoflavone A (12), were isolated from the leaves of Garcinia nigrolineata along with four known xanthones and friedelin. Among the xanthones, only nigrolineaxanthone N (5) showed significant antibacterial activity against methicillin-resistant Staphylococcus aureus.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Garcinia/chemistry , Isoflavones/isolation & purification , Isoflavones/pharmacology , Plants, Medicinal/chemistry , Quinones/isolation & purification , Quinones/pharmacology , Staphylococcus aureus/drug effects , Xanthones/isolation & purification , Xanthones/pharmacology , Anti-Bacterial Agents/chemistry , Dose-Response Relationship, Drug , Isoflavones/chemistry , Methicillin Resistance , Molecular Structure , Plant Leaves/chemistry , Quinones/chemistry , Thailand , Triterpenes/chemistry , Triterpenes/isolation & purification , Triterpenes/pharmacology , Xanthones/chemistryABSTRACT
Nine xanthones, nigrolineaxanthones A-I, together with nine known xanthones, were isolated from the crude methanol extract of the stem bark of Garcinia nigrolineata; two of which have previously been reported as synthetic xanthones. The structures were elucidated by analysis of spectroscopic data, especially using 1D and 2D NMR spectroscopic data.
Subject(s)
Garcinia/chemistry , Plant Bark/chemistry , Xanthones/isolation & purification , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Plant Stems/chemistry , Xanthones/chemistryABSTRACT
The latex of Garcinia scortechinii has yielded eight new caged-polyprenylated xanthones: two triprenylated (1 and 2) and five tetraprenylated xanthones (3-7) and one degraded caged-tetraprenylated xanthone (8), together with the known scortechinones A (9) and B (10). Their structures were elucidated by analysis of spectroscopic data and comparison of the NMR data with those reported previously.
