Antioxidant potential of Anogeissus latifolia. (1/18)

Anogeissus latifolia is widely used in the Indian indigenous system of medicine and is reported to contain leucocyanidins and tannoid principles like ellagic acid and its derivatives. In view of its wide use and its chemical composition, this study was aimed at examining the antioxidant activity of the extract of A. latifolia. The extract was studied for total antioxidant capacity, hydrogen-donating ability, nitric oxide, superoxide scavenging activity, hydrogen peroxide decomposition activity along with lipid peroxidation. Integral antioxidative capacity was determined by chemiluminescence assay. The extract was also studied for lipid peroxidation assay by thiobarbituric acid-reactive substances (TBARS) method using rat liver homogenate. The results indicate that A. latifolia extract has potent antioxidant activity. Also to ascertain the possible reason for the potent activity, percentage of gallic acid was estimated and was found to be 0.95%, which could be one of the reasons for potent antioxidant activity exhibited by the plant.  (+info)

Morphological and secretory characterization of extrafloral nectaries in plants of coastal Veracruz, Mexico. (2/18)

BACKGROUND AND AIMS: Morphological descriptions of the extrafloral nectaries (EFNs) of certain plant species are common in the literature, but they rarely relate morphology with histology, gland distribution and secretory attributes. In this study a morphological/secretory characterization of EFNs occurring on several plant species in a tropical coastal community is made and the implications of gland attributes discussed from a functional perspective. METHODS: The morphology and nectar secretion of the EFNs of 20 plant species are characterized through scanning electron microscopy, histochemical detection of reducing sugars (Fehling's reagent) and nectar volume/concentration estimates. KEY RESULTS: Sixty-five per cent of plant species in coastal communities had EFNs on vegetative structures and 35 % of species had glands on reproductive and vegetative organs. The Fabaceae is the plant family with the most species with EFNs and most diversity of gland morphologies. Four types of vascularized nectaries and four of glandular trichomes are described; sugar-secreting trichomes are characterized using Fehling's technique, and the first descriptions of unicellular and peltate trichomes functioning as EFNs are provided. Glands of ten plant species and six genera are described for the first time. Four plant species possess more than one morphological type of EFN. Eleven species have EFNs in more than one location or organ. More complex glands secrete more nectar, but are functionally homologous to the aggregations of numerous secretory trichomes on specific and valuable plant organs. CONCLUSION: Important diversity of EFN morphology was foundin the coastal plant community studied. Both vascularized and non-vascularized EFNs are observed in plants and, for the latter, previously non-existent morpho-secretory characterizations are provided with a methodological approach to study them. It is recommended that studies relating EFN attributes (i.e. morphology, distribution) with their differential visitation by insects (i.e. ants) and the cost of maintenance to the plants are carried out to understand the evolution of these glands.  (+info)

Seed shadow, seedling recruitment, and spatial distribution of Buchenavia capitata (Combretaceae) in a fragment of the Brazilian Atlantic forest. (3/18)

Here we describe the seed shadow, seedling recruitment, ontogenetic structure and spatial distribution of Buchenavia capitata (an emergent canopy tree) in a 380-ha fragment of the Atlantic forest in northeast Brazil. In particular, we examine seed distribution around 10 parental trees and both seedling recruitment and mortality, during an 18 month period beneath and around parental trees. Moreover, we describe: (1) B. capitata occurrence within treefall gaps; (2) population structure in terms of ontogenetic stages for the whole site; and (3) spatial distribution of adults within an area of 51 hectares. 99% of seeds were found beneath parent crowns (n = 4,236) and seed density reached 14.6 +/- 29.9 seeds/m2 (0-140 seeds/m2). 49% of all seeds germinated but seedling mortality reached 100% after an 18 month period. In addition, saplings of B. capitata were not found in forest understory and within 30 treefall gaps (94-2,350 m2). The adults showed an average DBH of 69.3 +/- 22.1 cm, were 19.2 +/- 2.9 m tall and presented a clumped spatial distribution. B. capitata matched some of the features presented by shade intolerant trees or large-gap specialists, and we hypothesize that low rates or even lack of long distance seed dispersal events may be reducing the probability of B. capitata seeds reaching suitable habitats for successful seedling recruitment and growth. Because of that (1) seedlings face high levels of early mortality; (2) there is no sapling recruitment at the study site; and (3) local population faces senility and it is threatened by local extinction.  (+info)

Spectral characterization of mangrove leaves in the Brazilian Amazonian Coast: Turiacu Bay, Maranhao State. (4/18)

Mangrove communities are tropical systems which have fewer species than tropical forests, especially in Latin America and display a single architecture, usually lacking the various strata commonly found in other forest ecosystems. The identification of mangrove communities by orbital data is not a difficult task but the most interesting challenge is to identify themselves by the dominant species. The first step toward that floristic identification is the spectral characterization of detached leaves. Leaves from four species of mangrove trees were spectrally characterized considering the Directional Hemispherical Reflectance Factor (DHRF) determined through radiometric measurements using an integrating sphere LICOR 1800 attached to a spectroradiometer SPECTRON SE-590. In the visible bands (0.45-0.69 microm) the button-shaped mangrove Conocarpus erectus was brighter and the red mangrove Rhizophora mangle was darker than the other two species which shows very close DHRF values. Otherwise the black mangrove Avicennia germinans and the white mangrove Laguncularia racemosa can be distinguished from one another in the Near Infra Red (NIR) region (0.76-0.90 microm and in this region of the spectrum the DHRF of C. erectus and R. mangle become very close.  (+info)

Phytochemistry and pharmacogenomics of natural products derived from traditional Chinese medicine and Chinese materia medica with activity against tumor cells. (5/18)

 (+info)

Dial organic carbon fluctuations in a mangrove tidal creek in Sepetiba bay, Southeast Brazil. (6/18)

The carbon (C) concentration and flux, as dissolved organic carbon (DOC), particulate organic carbon (POC) and macrodetritus (MD), were quantified through 4 tidal cycles in a mangrove tidal creek in Southeastern Brazil. DOC was the major fraction of the total C concentration, accounting for 68 and 61% of the total C concentration during ebb and flood periods respectively. Concentrations of DOC (Ebb = 3.41 +/- 0.57 mgC.L-1 and Flood = 3.55 +/- 0.76 mgC.L-1) and POC (Ebb = 1.73 +/- 0.99 mgC.L-1 and Flood = 1.28 +/- 0.45 mgC.L-1) were relatively similar during the four tidal cycles. Macrodetritus presented a wide variation with concentration peaks probably related to external forces, such as winds, which enrich the ebb flow with leaf litter. DOC and POC fluxes depended primarily on tidal and net water fluxes, whereas MD fluxes were not. The magnitude of the DOC and POC fluxes varied with the area flooded at high tide, but not the MD fluxes. DOC was the major form of carbon export to Sepetiba Bay. During the four tidal cycles, the forest exported a total of 1.2 kg of organic carbon per ha, mostly as DOC (60%), followed by POC (22%) and MD (18%).  (+info)

Hepatoprotective evaluation of Anogeissus latifolia: in vitro and in vivo studies. (7/18)

AIM: To evaluate the hepatoprotective activity of a hydroalcoholic extract of the bark of Anogeissus latifolia; in vitro in primary rat hepatocyte monolayer culture and in vivo in the liver of Wistar rats intoxicated by carbon tetrachloride (CCl(4)). METHODS: In the in vitro study, a primary hepatocyte monolayer culture was treated with CCl(4) and extract of Anogeissus latifolia. Hepatoprotective activity was demonstrated in the CCl(4) damaged primary monolayer culture. In the in vivo study, the hepatoprotective activity of a hydroalcoholic extract of Anogeissus latifolia was analyzed in liver injured CCl(4)-treated rats. Biochemical parameters including serum transaminases [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)] and alkaline phosphatase (ALP) in serum were analyzed. The biochemical findings were supplemented with histopathological examination of rat liver sections. RESULTS: In vitro: primary hepatocyte monolayer cultures were treated with CCl(4) and extract of Anogeissus latifolia. A protective activity could be demonstrated in the CCl(4) damaged primary monolayer culture. In vivo: Hydroalcoholic extract of Anogeissus latifolia (300 mg/kg) was found to have protective activity in rats with CCl(4)-induced liver damage as judged from serum marker enzyme activity. CONCLUSION: The above findings lead to the conclusion that the hydroalcoholic extract of Anogeissus latifolia is hepatoprotective. Hence, we suggest that the inclusion of this plant in the management of liver disorders is justified.  (+info)

Commercial activities and subsistence utilization of mangrove forests around the Wouri estuary and the Douala-Edea reserve (Cameroon). (8/18)

 (+info)

• 1
• 2
• 3