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Free Radical Scavenging Activity of Kielmeyera variabilis (Clusiaceae)  [PDF]
Aline Coqueiro,Luis Octávio Regasini,Scheila Cristina Gutkoski Skrzek,Marcos Mar?al Ferreira Queiroz,Dulce Helena Siqueira Silva,Vanderlan da Silva Bolzani
Molecules , 2013, DOI: 10.3390/molecules18022376
Abstract: As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH · (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS · + [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves of K. variabilis displayed the strongest activity (IC 50 of 3.5 ± 0.3 and 4.4 ± 0.2 μg mL ?1 for DPPH · and 6.6 ± 0.4 and 3.1 ± 0.1 μg mL ?1 for ABTS · +, respectively). Chromatographic fractionation of the most potent fractions led to identification of three flavonols with previously described antioxidant activity, quercitrin ( 1), quercetin-3- O-b-glucoside ( 3), and quercetin-3- O-b-galactoside ( 4), and of one biflavone, podocarpusflavone A ( 2). This is the first time that the presence of these flavonoids in Kielmeyera variabilis has been reported.
Antibacterial xanthones from Kielmeyera variabilis mart. (Clusiaceae)
Pinheiro, Lucimar;Nakamura, Celso Vataru;Dias Filho, Benedito Prado;Ferreira, Antonio Gilberto;Young, Maria Claudia Marx;Cortez, Aparicio Garcia;
Memórias do Instituto Oswaldo Cruz , 2003, DOI: 10.1590/S0074-02762003000400023
Abstract: the bioassay-guided fractionation of stems from kielmeyera variabilis, traditionally used in brazilian folk medicine, yielded assiguxanthone-b (1), kielcorin (4), 2,5-dihydroxybenzoic acid (3), and a mixture of xanthones containing assiguxanthone-b (1) and 1,3,5,6-tetrahydroxy-2-prenylxanthone (2) (1:1 w/w). the xanthone mixture inhibited staphylococcus aureus and bacillus subtilis at a concentration of 6.25 μg/ml. when tested alone, the minimal inhibitory concentration of assiguxanthone-b was 25 μg/ml against b. subtilis. kielcorin and 2,5-dihydroxybenzoic acid were inactive against both strains. none of the fractions was active against escherichia coli or pseudomonas aeruginosa. viable cells of s. aureus were reduced by a 1-3 log cfu/ml within 12 h after exposure of one to eight times the mic of the xanthone mixture. it is not known whether the tetrahydroxy-2-prenylxanthone or other components of the xanthone mixture are responsible for the main antibacterial activity or whether additive or synergistic action is involved
Antibacterial xanthones from Kielmeyera variabilis mart. (Clusiaceae)  [cached]
Pinheiro Lucimar,Nakamura Celso Vataru,Dias Filho Benedito Prado,Ferreira Antonio Gilberto
Memórias do Instituto Oswaldo Cruz , 2003,
Abstract: The bioassay-guided fractionation of stems from Kielmeyera variabilis, traditionally used in Brazilian folk medicine, yielded assiguxanthone-B (1), kielcorin (4), 2,5-dihydroxybenzoic acid (3), and a mixture of xanthones containing assiguxanthone-B (1) and 1,3,5,6-tetrahydroxy-2-prenylxanthone (2) (1:1 w/w). The xanthone mixture inhibited Staphylococcus aureus and Bacillus subtilis at a concentration of 6.25 μg/ml. When tested alone, the minimal inhibitory concentration of assiguxanthone-B was 25 μg/ml against B. subtilis. Kielcorin and 2,5-dihydroxybenzoic acid were inactive against both strains. None of the fractions was active against Escherichia coli or Pseudomonas aeruginosa. Viable cells of S. aureus were reduced by a 1-3 log CFU/ml within 12 h after exposure of one to eight times the MIC of the xanthone mixture. It is not known whether the tetrahydroxy-2-prenylxanthone or other components of the xanthone mixture are responsible for the main antibacterial activity or whether additive or synergistic action is involved
Morphology and anatomy of developing fruits and seeds of Vismia guianensis (Aubl.) Choisy (Clusiaceae)
MOUR?O, K. S. M.;BELTRATI, C. M.;
Revista Brasileira de Biologia , 2001, DOI: 10.1590/S0034-71082001000100019
Abstract: morphological, structural and developmental features of fruits and seeds of vismia guianensis (aubl.) choisy. are here presented, with the purpose to elucidate their structure and to contribute to taxonomical and ecological studies of the family. the fruit is a berry and the "rind" is constituted by the exocarp and by the subepidermal layers which constitute the mesocarp. the reddish pulp, rich in starch, is constituted by the parenchymatic mesocarp, with branched secretory ducts and vascular bundles, joined with the endocarp, which arises from a ventral meristem. the bitegmic, anatropous ovules, provided by the endothelium, develop into anatropous, bitegmic and exalbuminous seeds. the reddish uniseriate testa shows phenolic contents. the tegmen becomes crushed resting only the uniseriate exotegmen with undulate, thick walled and lignified cells, which contain a number of calcium oxalate prismatic crystals. the embryo, rich in lipids, is straight and shows foliaceous cotyledons.
Morphology and anatomy of developing fruits and seeds of Vismia guianensis (Aubl.) Choisy (Clusiaceae)
MOUR?O K. S. M.,BELTRATI C. M.
Revista Brasileira de Biologia , 2001,
Abstract: Morphological, structural and developmental features of fruits and seeds of Vismia guianensis (Aubl.) Choisy. are here presented, with the purpose to elucidate their structure and to contribute to taxonomical and ecological studies of the family. The fruit is a berry and the "rind" is constituted by the exocarp and by the subepidermal layers which constitute the mesocarp. The reddish pulp, rich in starch, is constituted by the parenchymatic mesocarp, with branched secretory ducts and vascular bundles, joined with the endocarp, which arises from a ventral meristem. The bitegmic, anatropous ovules, provided by the endothelium, develop into anatropous, bitegmic and exalbuminous seeds. The reddish uniseriate testa shows phenolic contents. The tegmen becomes crushed resting only the uniseriate exotegmen with undulate, thick walled and lignified cells, which contain a number of calcium oxalate prismatic crystals. The embryo, rich in lipids, is straight and shows foliaceous cotyledons.
ANATOMICAL CHARACTERIZATION AND MICROCHEMISTRY OF VISMIA GUIANENSIS (AUBL.) CHOISY (CLUSIACEAE) BLADE LEAF
Jose Otavio Carrera Silva Junior et al.
International Journal of Pharmaceutical Sciences and Research , 2012,
Abstract: Vismia guianensis (Aubl.) Choisy is a tree that belongs to the secondary vegetation in rainforests. This study aimed to perform anatomy analysis by light microscopy; scanning and microchemistry of the leaves of V. guianensis. Tri stratified upper epidermis with intense cutinization and unistratified inferior epidermis was observed. The stomata found are paracytic and the trichomes arranged in rosettes are glandular, multicellular, stellate shape covered with cuticle, which were present on the abaxial surface. Parenchyma cells with idioblasts containing druses of calcium oxalate crystals were also found. The mesophyll is dorsiventral and the midrib is concave on the adaxial surface and convex on the opposite surface. The microchemical tests detected the presence of starch grains in the chlorophyll cells and phenolic compounds dispersed in the palisade tissue and abaxial surface. Alkaloids in the epidermis and in the sclerenchyma cells surrounding the vascular bundles and the midrib xylem, dispersed flavonoid in the palisade parenchyma and trichomes, fatty substances as content of the secretory ducts and reducing sugars in the palisade and epidermal cells were found. These anatomical features were fundamental in the identification and characterization of the species.
Effects of prescribed fires on the survival and release of seeds of Kielmeyera coriacea (Spr.) Mart. (Clusiaceae) in savannas of Central Brazil
Cirne, Paulo;Miranda, Heloisa Sinátora;
Brazilian Journal of Plant Physiology , 2008, DOI: 10.1590/S1677-04202008000300004
Abstract: effects of prescribed fires on survival and release of seeds of the woody species kielmeyera coriacea (clusiaceae) were investigated in two plots of cerrado sensu stricto, a savanna vegetation of central brazil. the first plot was burnt in june, at the beginning of the dry season, and the second in august, in the middle of the dry season. seed survival was measured after fire in both areas and related to internal and external fruit temperatures measured during the june fire. the proportion of open fruits per individual of k. coriacea was also assessed at two-week intervals. maximum external temperatures during fire (393 to 734oc) were strongly reduced inside the fruits (61 to 63oc). before the june fire, the majority of the fruits were closed in both plots. most fruits in the june plot opened within two weeks following the burning while, in the same period, most fruits remained closed in the august plot. fifteen days after the prescribed fire in the august plot most fruits opened, as observed in the june plot. no germination was observed in seeds from closed fruits collected before the fire, while those from fruits that were closed during the burning showed a high mean germination rate (june = 79 ± 12%; august = 69 ± 14%). the results indicate that fruits of k. coriacea are good insulators for seeds during fires and that seed release is anticipated independently of the burning season.
Estudo fitoquímico e avalia??o da atividade moluscicida da Kielmeyera variabilis Mart (Clusiaceae)
Pinheiro, Lucimar;Cortez, Diógenes Aparício Garcia;Vidotti, Gentil J.;Young, Maria Claudia M.;Ferreira, Ant?nio Gilberto;
Química Nova , 2003, DOI: 10.1590/S0100-40422003000200002
Abstract: methanol extract obtained from kielmeyera variabilis stems showed significant molluscicidal activity against biomphalaria glabrata. the phytochemical studies of the plants stem to the isolation of three xanthones (assiguxanthone-b, kielcorin and 1,3,5,6-tetrahtydroxy-2-prenylxanthone) and a organic acid (2,5-dihydroxy benzoic acid). the structures of these compounds were identified by ir, ms, 1h and 13c nmr spectral analysis and comparison with literature data.
Estudo fitoquímico e avalia o da atividade moluscicida da Kielmeyera variabilis Mart (Clusiaceae)  [cached]
Pinheiro Lucimar,Cortez Diógenes Aparício Garcia,Vidotti Gentil J.,Young Maria Claudia M.
Química Nova , 2003,
Abstract: Methanol extract obtained from Kielmeyera variabilis stems showed significant molluscicidal activity against Biomphalaria glabrata. The phytochemical studies of the plants stem to the isolation of three xanthones (assiguxanthone-B, kielcorin and 1,3,5,6-tetrahtydroxy-2-prenylxanthone) and a organic acid (2,5-dihydroxy benzoic acid). The structures of these compounds were identified by IR, MS, 1H and 13C NMR spectral analysis and comparison with literature data.
Xantonas, triterpenos e atividade antibacteriana do extrato em diclorometano de Kielmeyera cuspidata Saddi, Clusiaceae
Sobral, Ivoneide S.;Souza-Neta, Lourdes C.;Costa, Giselle. A. N.;Guedes, Maria L. S.;Martins, Dirceu;Cruz, Frederico G.;
Revista Brasileira de Farmacognosia , 2009, DOI: 10.1590/S0102-695X2009000500006
Abstract: from the dichloromethane extract of trunk of kielmeyera cuspidata five xanthones were isolated, 1,6-dihydroxy-3,5-dimethoxyxanthone, 2-hydroxy-1-methoxyxanthone, 2,3-methylenedioxyxanthone, 4-hydroxy-2,3-methylenedioxyxanthone and 3-hydroxy-2,4-dimethoxyxanthone and two triterpenes α-amirin and β-amirin. the extract displayed toxicity against artemia salina and exhibited antibacterial activity against micrococcus luteus, bacillus subitilis, staphylococcus aureus and streptococcus mutans and it was not active against escherichia coli, pseudomonas aeruginosa and salmonela choleraesuis.
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