Showing papers on "Excoecaria agallocha published in 2008"

Vegetation dynamics in the Bangladesh Sundarbans mangroves: a review of forest inventories

Abstract: The Sundarbans, the largest contiguous mangrove forest in the world, covers 6,017 km2 of the coastal zone of Bangladesh. Heritiera fomes Buch.-Ham., Excoecaria agallocha L. and Ceriops decandra (Griff.) Ding Hou jointly cover 95% of the forest area. In this study, the results of four forest inventories have been analyzed to understand observed vegetation dynamics of the Sundarbans from 1926 to 1997. The diversity of forest types has been gradually reduced over time, but H. fomes and E. agallocha have maintained their dominance over large portions of the forest. H. fomes is spread over 67% of the vegetated area of the forest, concentrated mostly in the northeastern area, and constitutes 75% of the density of trees with >15 cm dbh. The distribution and stem density of H. fomes show negative relationships with that of E. agallocha and C. decandra. In terms of coverage, E. agallocha is the most common species, spread over 74% of the vegetated area of the forest, and constitutes 39% of the density of trees with >2.5 cm dbh. On a longer timeframe (1926–1997), the dominance (coverage and density of larger diameter trees) of H. fomes as well as that of E. agallocha is declining. Even on parameters such as density of trees with >15 cm dbh, the dominance of E. agallocha is declining at a much greater rate than H. fomes. This observation contradicts the successional schemes proposed by different authors. This might indicate that theorizing successional schemes based on short-term observations on vegetation dynamics is not sufficient. The effect of human interference, changes in hydroedaphic condition and species interaction should be taken into consideration during explaining observed vegetation dynamics. Moreover, the need to understand vegetation trajectories at the micro-scale should be emphasized.

Bioactivity of Excoecaria agallocha

Abstract: The results of neuropharmacological, microbiological and toxicological studies on the ethanol extract of the bark of Excoecaria agallocha are reported. The extract (100 and 200 mg/kg dosages) was found to produce a profound decrease in exploratory activity in a dose-dependent manner. It also showed a marked sedative effect as evidenced by a significant reduction in gross behaviour and potentiation of sodium thiopental-induced sleeping time. The totality of these effects showed that the extract possesses depressant action on the central nervous system (CNS). The extract of E. agallocha exhibited significant in vitro antibacterial activity against Staphylococcus aureus, Shigella dysenteriae, Shigella sonnei and Enterococci with the zones of inhibition ranging from 11 to 15 mm. While the extract showed considerable brine shrimp toxicity (LD50 = 20 mg/mL), it displayed only low level of toxicity in mice.

In vitro antioxidant property of the extract of excoecaria agallocha (euphorbiaceae)

Abstract: Background and objectives: Excoecaria agallocha L. (Family: Euphorbiaceae) is a Bangladeshi medicinal plant found predominantly in the tidal forests and swamps of the Sundarbans and other coastal areas in Bangladesh. As part of our on-going phytochemical and bioactivity studies on medicinal plants from Bangladeshi flora, the in vitro antioxidant property on the bark of this plant was evaluated. Methods: The hydroalcohol extract of the dried and ground bark of E. agallocha was assessed for antioxidant activity using a series of well-established assays including the 2,2diphenyl-1-picrylhydrazyl (DPPH), the lipid peroxidation by thiobarbituric acid (TBA), the reducing power, the nitric oxide (NO.) and the hydrogen peroxide (H2O2) scavenging assays. Results: In the DPPH, the NO and the H2O2 scavenging assays, the extract of E. agallocha displayed significant antioxidant activities with the IC50 values of 179.16, 120.24 and 134.29 µg/ml, respectively. The reducing power of the extract increased dose-dependently, and the extract reduced the most Fe 3+ ions to the extent less than butylated hydroxy toluene (BHT). In the lipid peroxidation assay, the extract showed significant inhibition of peroxidation effect at all concentrations, with an IC50 value of 189.27 µg/ml. Conclusion: Since reactive oxygen species are important contributors to serious ailments such as atherosclerosis, alcoholic liver cirrhosis and cancer, the antioxidant property of the extract of E. agallocha as observed in the present study might be useful for the development of newer and more potent antioxidants.

Antinociceptive and gastroprotective effect of the crude ethanolic extracts of excoecaria agallocha linn.

Abstract: The effect of alcoholic extracts of bark from Excoecaria. agallocha Linn. (Family: Euphorbiaceae) was evaluated in experimental models of pain and ulceration. Crude extracts of Excoecaria agallocha (300 mg/kg dose) showed maximum time needed for the response against thermal stimuli (6.72±0.43 seconds) which is comparable to diclofenac sodium (8.20±0.21seconds) in the hot plate test. Hot tail immersion test also showed similar results as in hot plate test. The bark extracts at 500 and 250 mg/kg showed significant reduction in acetic acid induced writhings in mice with a maximum effect of 53.87% reduction at 500 mg/kg dose. The effect produced by the alcoholic extract at the highest dose was comparable to that of diclofenac sodium at 100 mg/kg (70.56%). It has also been seen anti-ulcerogenic activity compared to acetylsalicylic acid, which may be due to the protective effect of the extract. The result suggest that the analgesic effect of the extract as claimed in folklore medicine, which may be mediated via both peripheral and central mechanism having gastro-protective effect.

Spectral reflectance properties of mangrove species of the Muthupettai mangrove environment, Tamil Nadu

Abstract: In the Muthupettai mangrove environment, spectral properties of six mangrove species viz. Avicennia marina, Aegiceras corniculatum, Excoecaria agallocha, Acanthus ilicifolius, Suaeda monoica and S. maritima was studied using Multi band Ground Truth Radiometer (Model-041). The study found that the chlorophyll concentration of different mangrove leaves varies between 0.05 and 0.36 mg g -1 , registering the minimum in S. maritima and maximum in E. agallocha. Interestingly species with higher chlorophyll concentration showed lower reflectance values alteast in the spectral bands 1 and 2. E. agallocha registered 0.36 mg g -1 of chlorophyll while it recorded only 2.18 and 2.43% reflectance where as S. maritima recorded 3.16 and 3.27% of reflectance in bands 1 and 2. This indicates chlorophyll concentration is one of major factors responsible in determining the reflectance pattern of the pant communities. The spectral properties of mangroves were largely differed with that of the water and soil samples collected from the same locations, these results favourd the utilization of remotely sensed data for depicting various water and soil quality parameters from that of mangrove species in the mangrove environment. This study also found that the difference in reflectance of mangroves at canopy level is not only influenced by the chlorophyll content of species but also by the prevailing environmental condition and background reflectance of soil and water as well

Triterpenoids and steroids from Excoecaria agallocha

Abstract: OBJECTIVE To study the chemical constituents of Excoecaria agallocha L. METHOD The constituents were isolated and purified by repeated column chromatography and their structures were elucidated by spectroscopic analysis. RESULT Six triterpenoids including taraxerone (1), beta-amyrin acetate (2), 3beta-[(2E,4E)-6-oxo-decadienoyloxy]-olean-12-ene (3), taraxerol (4), acetylaleuritolic acid (5), and cycloart-22-ene-3beta, 25-diol (6), and three steroids including beta-sitostenone (7), (24R)-24-ethylcholesta-4,22-dien-3-one (8), and beta-sitosterol (9) were isolated and identified from the stems and twigs of the mangrove plant E. agallocha. CONCLUSION Compounds 5-8 were isolated from E. agallocha for the first time.

Elucidation of Excogallochaols A—D, Four Unusual Diterpenoids from the Chinese Mangrove Excoecaria agallocha.

Abstract: Diterpenoids, excoagallochaols A–D ( 1 – 4 ), with an unprecedented skeleton, were isolated from the ethyl acetate extract of the stems and leaves of the mangrove Excoecaria agallocha L. The structures of these metabolites were elucidated on the basis of detailed analysis of their spectroscopic data and by comparison with those of related compounds reported in literature.

IDENTIFIKASI VEGETASI MANGROVE DI SEGORO ANAK SELATAN, TAMAN NASIONAL ALAS PURWO, BANYUWANGI, JAWA TIMUR Identification Of Mangrove Vegetation In South Segoro Anak, National Sanctuary Of Alas Purwo, Banyuwangi, East Java

Abstract: Selection of systematic sampling at South Segoro Anak areas as vast as 4 % of mangrove vast, following the direction of pilot line from Block of PAL to Block of Randu. The parameters observed is diamater of pillar/tree highly 1.3 meters, amount pillar/tree, weaned and seedling at every plots and plant type of mangrove existing in a plot. This research is made on 16 April-28 June 2006. Result of vegetation analysis with systematic sampling method at pillar level, weaned and seedling be obtained type of mangrove they are : Avicennia alba, Avicennia lanata, Avicennia marina, Avicennia officinalis, Bruguiera gymnorrhyza, Ceriops decandra, Ceriops tagal, Excoecaria agallocha, Lumnitzera racemosa, Rhizophora mucronata, Rhizophora apiculata, Schypiphora hydrophyllacea, Sonneratia alba, Sonneratia caseolaris, Xylocarpus granatum, Xylocarpus molluccennis, Heritiera littoralis. They are forms regular or uniform distribution pattern. Calculation of Morishita index at plant of mangrove in South Segoro Anak, Alas Purwo National Park of Banyuwangi-East Java can be described that is spreading pattern is regular, because value of IS which less than 1 (one). The regular or uniform spreading is reflecting the existence of negative individual interaction, like emulation to obtaining space, nutrition and sunlight.