Bruguiera sexangula （Lout） Poir., a threatened mangrove tree, was inoculated with beneficial microbes in a nursery to assess any improvements in growth and bio- mass. From soil samples from the rhizosphere of B. sex...Bruguiera sexangula （Lout） Poir., a threatened mangrove tree, was inoculated with beneficial microbes in a nursery to assess any improvements in growth and bio- mass. From soil samples from the rhizosphere of B. sexangula in a mangrove forest in Panangadu of Kerala India, nitrogen-fixing bacteria Azotobacter chroococcum and Azospirillum brasilense were isolated. The phosphatesolubilising bacterium Bacillus megaterium and potassiummobilizing bacteria Frateruria aurantia were also isolated and cultured on suitable media. Later, ripe propagules of B. sexangula were collected from matured trees and raised in sterilized soil bags （13 × 25 cm） containing sterilized soil and sand （2：1 ratio）. The cultured beneficial microbes were propagated and used to inoculate the ripe propagules of B. sexangula and maintained in the nursery for 6 months. After 6 months, growth and biomass of the inoculated propagules were greater than for the uninoculated control propagules. Shoot length, number of leaves, stem girth and root length were also significantly greater than in the controls. This study showed that the mangrove-specific beneficial microbes influenced the growth of B. sexangula展开更多
The distribution patterns of mangrove Bruguiera gymnorrhiza population s in southern China are analyzed using the box-counting method of fractal theory. The patterns of B. gymnorrhiza populations could be thought of a...The distribution patterns of mangrove Bruguiera gymnorrhiza population s in southern China are analyzed using the box-counting method of fractal theory. The patterns of B. gymnorrhiza populations could be thought of as fractals as they exhibit self-similarity within the range of scale considered. Their fractal dimensions are not integer but fractional, ranging from 1.04 to 1.51. The unoccupied dimensions change from 0.49 to 0.96. The combined conditions of population density, pattern type and aggregation intensity together influence the values of fractal dimensions of patterns. The box counting is a useful and efficient method to investigate the complexity of patterns. Fractal dimension may be a most desirable and appropriate index for quantifying the horizontal spatial microstructure and fractal behaviors of patterns over a certain range of scales.展开更多
Objective:To evaluate the antimicrobial potential of partially purified leaf,bark and root extracts obtained from two mangrove species Rhizophora apiculata and Bruguiera gymnorrhiza from South Andaman against clinical...Objective:To evaluate the antimicrobial potential of partially purified leaf,bark and root extracts obtained from two mangrove species Rhizophora apiculata and Bruguiera gymnorrhiza from South Andaman against clinical bacterial and fungal pathogens.Methods:Roots,bark and leaves were dried in the shade and subjected to organic solvent extraction.Antibacterial and antifungal activities were performed by agar well diffusion technique.Column purified extracts were analyzed by high performance liquid chromatography for compound identification.Results:Results of the partially purified extracts were analyzed by column chromatography.Fractions collected by high performance liquid chromatography exhibited a wide range of antimicrobial activities against several bacterial and fungal pathogens.Fungal pathogen Aspergillus niger(25 mm)was found to be more sensitive against the mangrove extracts as compared with Klebsiella pneumoniae(23 mm),Escherichia coli,Shigella flexneri,Salmonella typhi(22 mm).Active fractions were identified as tannin compounds based on the peaks obtained by high performance liquid chromatography.Conclusions:Present findings reveal that mangrove bark,roots,and leaves contain valuable metabolites,which have significant importance in the pharmacological industries.Hence,this study suggests that these two mangrove plants Rhizophora apiculata and Bruguiera gymnorrhiza are potential candidates for discovering antimicrobial compounds against clinical pathogens.展开更多
基金funded by the Program of Department of Science and Technology,New Delhi,Government of India(No.IF110661)
文摘Bruguiera sexangula （Lout） Poir., a threatened mangrove tree, was inoculated with beneficial microbes in a nursery to assess any improvements in growth and bio- mass. From soil samples from the rhizosphere of B. sexangula in a mangrove forest in Panangadu of Kerala India, nitrogen-fixing bacteria Azotobacter chroococcum and Azospirillum brasilense were isolated. The phosphatesolubilising bacterium Bacillus megaterium and potassiummobilizing bacteria Frateruria aurantia were also isolated and cultured on suitable media. Later, ripe propagules of B. sexangula were collected from matured trees and raised in sterilized soil bags （13 × 25 cm） containing sterilized soil and sand （2：1 ratio）. The cultured beneficial microbes were propagated and used to inoculate the ripe propagules of B. sexangula and maintained in the nursery for 6 months. After 6 months, growth and biomass of the inoculated propagules were greater than for the uninoculated control propagules. Shoot length, number of leaves, stem girth and root length were also significantly greater than in the controls. This study showed that the mangrove-specific beneficial microbes influenced the growth of B. sexangula
基金The paper is supported by grants from the NSFC (No. 39825106 and 39860023).
文摘The distribution patterns of mangrove Bruguiera gymnorrhiza population s in southern China are analyzed using the box-counting method of fractal theory. The patterns of B. gymnorrhiza populations could be thought of as fractals as they exhibit self-similarity within the range of scale considered. Their fractal dimensions are not integer but fractional, ranging from 1.04 to 1.51. The unoccupied dimensions change from 0.49 to 0.96. The combined conditions of population density, pattern type and aggregation intensity together influence the values of fractal dimensions of patterns. The box counting is a useful and efficient method to investigate the complexity of patterns. Fractal dimension may be a most desirable and appropriate index for quantifying the horizontal spatial microstructure and fractal behaviors of patterns over a certain range of scales.
文摘Objective:To evaluate the antimicrobial potential of partially purified leaf,bark and root extracts obtained from two mangrove species Rhizophora apiculata and Bruguiera gymnorrhiza from South Andaman against clinical bacterial and fungal pathogens.Methods:Roots,bark and leaves were dried in the shade and subjected to organic solvent extraction.Antibacterial and antifungal activities were performed by agar well diffusion technique.Column purified extracts were analyzed by high performance liquid chromatography for compound identification.Results:Results of the partially purified extracts were analyzed by column chromatography.Fractions collected by high performance liquid chromatography exhibited a wide range of antimicrobial activities against several bacterial and fungal pathogens.Fungal pathogen Aspergillus niger(25 mm)was found to be more sensitive against the mangrove extracts as compared with Klebsiella pneumoniae(23 mm),Escherichia coli,Shigella flexneri,Salmonella typhi(22 mm).Active fractions were identified as tannin compounds based on the peaks obtained by high performance liquid chromatography.Conclusions:Present findings reveal that mangrove bark,roots,and leaves contain valuable metabolites,which have significant importance in the pharmacological industries.Hence,this study suggests that these two mangrove plants Rhizophora apiculata and Bruguiera gymnorrhiza are potential candidates for discovering antimicrobial compounds against clinical pathogens.
