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Quantitative determination of maitenin and 22 beta-hydroxymaitenin in callus of Maytenus aquifolium (Celastraceae) by reverse phase high performance liquid chromatography
(Wiley-Blackwell, 1998-09-01)
Explants of Maytenus aquifolium were induced to form callus and, subsequently, suspension cultures. The isolation of natural products from callus led to the identification of the cytotoxic triterpene quinonemethides, ...
Circadian rhythm of anti-fungal prenylated chromene in leaves of Piper aduncum
(Wiley-Blackwell, 2005-07-01)
Leaves of Piper aduncum accumulate the anti-fungal chromenes methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (1) and methyl 2,2-dimethyl-8-(3'-methyl-2'-butenyl)-2H-1-chromene-6-carboxylate (2). The enzymatic formation of ...
Optimisation of conditions for the extraction of casearins from Casearia sylvestris using response surface methodology
(Wiley-Blackwell, 2006-05-01)
Optimal conditions for the extraction of casearins from Casearia sylvestris were determined using response surface methodology. The maceration and sonication extraction techniques were performed using a 3 x 3 x 3 full ...
Prediction of occurrences of diverse chemical classes in the Asteraceae through artificial neural networks
(Wiley-Blackwell, 2004-11-01)
The training and the application of a neural network system for the prediction of occurrences of secondary metabolites belonging to diverse chemical classes in the Asteraceae is described. From a database containing about ...
Quantitative determination of cytotoxic friedo-nor-oleanane derivatives from five morphological types of Maytenus ilicifolia (Celastraceae) by reverse-phase high-performance liquid chromatography
(Wiley-Blackwell, 2002-03-01)
Five different morphological types of Maytenus ilicifolia of the same age and harvested under the same conditions showed distinct accumulations of some friedo-nor-oleananes. A rapid, sensitive and reliable reverse-phase ...
Chemical constituents and antioxidant activity from leaves extracts of terminalia fogiafolia mart. et zucc
(Soc Brasileira Quimica, 2009-01-01)
CHEMICAL CONSTITUENTS and ANTIOXIDANT ACTIVITY FROM LEAVES EXTRACTS of Terminalia fagifolia Mart. et Zucc. Phytochemical investigation of ethanolic leaves extracts of T. fagifolia led to the isolation of (+)-catechin, ...
Iridoid and seco-iridoid glucosides from Chioccoca alba (Rubiaceae)
(Elsevier B.V., 1999-07-01)
Phytochemical investigation of Chioccoca alba afforded three new iridoids, alboside I, alboside II and alboside III, and a new seco-iridoid alboside V. Alboside IV showed moderate activity towards the DNA repair-deficient ...
Lipophyllic antioxidants from Iryanthera juruensis fruits
(Elsevier B.V., 2001-06-01)
The phytochemical investigation of the hexane extract of I,:Iryanthera juruensis (Myristicaceae) fruits led to the isolation of two tocotrienols and four lignans which exhibited antioxidant activity towards beta -carotene ...
Chemical investigation and effects of the tea of Passiflora alata on biochemical parameters in rats
(Elsevier B.V., 2005-01-15)
Passiflora alata (Passifloraceae) is a native plant from the South-America tropical forest that provides a much apreciated fruit known as maracuja-doce. Although tea of the leaves of Passiflora alata is used in folk medicine ...