This review examines the chemical compositions and bioactivities of mangrove plants belonging to the Rhizophoraceae family.The Rhizophoraceae family of true mangrove plants is the most common and is also widely distri...This review examines the chemical compositions and bioactivities of mangrove plants belonging to the Rhizophoraceae family.The Rhizophoraceae family of true mangrove plants is the most common and is also widely distributed species.It consists of 24 species across four genera.Of the 24 species,12 species remain unexamined for their phytochemical constituents.There have been 268 metabolites reported from 16 species.The key phytochemical constituents identified across the family are the diterpenoids and triterpenoids.The major diterpenoids include pimaranes,beyeranes,kaurenes,dolabranes and labdanes whereas the significant triterpenoids are lupanes,dammaranes and oleananes.Disulphides,dolabranes and labdanes are considered to be the chemotaxonomic markers of the genera Bruguiera,Ceriops and Rhizophora respectively.展开更多
Objective:To evaluate the antibacterial activity of foliar extracts of Rhizophora mucronnata(R. mucronata) against pathogens belonging to human origin and to identify the compound hitherto unprecedented in nature by G...Objective:To evaluate the antibacterial activity of foliar extracts of Rhizophora mucronnata(R. mucronata) against pathogens belonging to human origin and to identify the compound hitherto unprecedented in nature by GC-MS analysis.Methods:Soxhlet extraction method was used to get the corresponding extracts of ethanol,petroleum ether,acetone,methanol and ethyl acetate.The antimicrobial activities of the organic solvent extracts on the various test organisms using agar well diffusion technique were carried out.Ethyl acetate extract exhibited promising antimicrobial activity and hence minimum inhibitory concentration(MIC) was performed for the same.Column chromatography was done for partial purification of crude extract and fractions were analyzed by GC-MS.Results:A column chromatographic fractionation of the extracts and further UV visible and GS-MS analysis suggested the active principle compound were a mixture of squalene(19.19%),n-Hexadecanoic acid(6.59%),phytol(4.74%).2-cyclohexane-l- one, 4-hydroxy-3,5,(4.20%) and oleic acid(2.88%).Conclusions:The results are good enough to serve to transform the practice of research in this sub field across a range of different benefit streams that include drug development.By and large this type of structure analyses are most important as aids to more rational decision taking in safety models versus effectiveness.In general,structural data provide prima facie support for drug hypothesis.展开更多
Studies on the corrosion behaviour of mild steel electrodes in inhibited hydrochloric acid are described. Conventional weight loss measurements show that a maximum concentration of 140 ppm of tannin from Rhizophora ra...Studies on the corrosion behaviour of mild steel electrodes in inhibited hydrochloric acid are described. Conventional weight loss measurements show that a maximum concentration of 140 ppm of tannin from Rhizophora racemosa is required to achieve 72% corrosion inhibition. Similar concentration of tannin: H3PO4 in ratio 1:1 gave 61% inhibition efficiency, whereas efficiency obtained for phosphoric acid as inhibitor in the same environment was 55%. Corrosion rates obtained over six hours of exposure in 1M HCl solution at inhibitor concentrations of 140 ppm are 2 mA/cm2, 2.4 mA/cm2, 2.6 mA/cm2 and 6 mA/cm2 for tannin, tannin/H3PO4 and H3PO4-inhibited and uninhibited specimens respectively. Natural atmospheric exposure studies revealed that specimens treated in H3PO4 resisted corrosion for three weeks, while tannin treated specimens suffered corrosion attack after one week of exposure tests.展开更多
This paper deals with the distribution pattern type,aggregative intensity,pattern scaleand dynamics of plant populations of Rhizophora stylosa community in Yingluo Bay of Guangxi.The measured results show that R.stylo...This paper deals with the distribution pattern type,aggregative intensity,pattern scaleand dynamics of plant populations of Rhizophora stylosa community in Yingluo Bay of Guangxi.The measured results show that R.stylosa population is an aggregated distribution,while thepopulations of Kandelia candel,Bruguiera gymnorrhiza and Aegiceras corniculatum appear asrandom distribution.The plant population distribution pattern changes,along with the populationdevelopment and the succession of the community.展开更多
Background： Progress of forest production in response to the environment requires a quantitative understanding of leaf area development. Therefore, it is necessary to investigate the dynamics of seasonal crown foliag...Background： Progress of forest production in response to the environment requires a quantitative understanding of leaf area development. Therefore, it is necessary to investigate the dynamics of seasonal crown foliage in order to understand the productivity of mangroves, which play an important role in the subtropical and tropical coastlines of the world. Method： Crown foliage dynamics of the mangrove Rhizophora styloso were studies to reveal patterns of leaf recruitment, survival and seasonal leaf area growth. Results： Flushing of leaves occurred throughout the year, but both flushing and leaf area growth pattern of leaves varied with season. Maximum flushing occurred in summer, but leaf areas did not differ significantly with season. The half-expansion period is longer, and the intrinsic rate of increase was lower in winter. Summer flushed leaves grew faster at their initial stage and reached their maximum area over a shorter period of time. The difference in temperature and air vapor pressure deficit （VPD） between summer and winter contributed to the present dynamics of foliage patterns. The mean leaf longevity was estimated to be 13.1 month. The crown foliage area was almost stable throughout the year. Conclusions： Homeostatic control of the crown foliage area may be accompanied by the existence of ecophysiological mechanisms in R. stylosa. Integrating crown foliage dynamics into forest models represents an important step towards incorporating physiological mechanisms into the models for predicting growth responses to environmental changes and for understanding the complex responses of tree growth and litter production.展开更多
Forty-three trees (23 Rhizophora mucronata and 20 Avicennia marina) were studied for the establishment of allometric relationships between the aboveground biomass “y” and the following dendrometric variables “x”: ...Forty-three trees (23 Rhizophora mucronata and 20 Avicennia marina) were studied for the establishment of allometric relationships between the aboveground biomass “y” and the following dendrometric variables “x”: diameter at breast height DBH, (DBH)2 product Ht (where Ht is the total height), and the basal circumference Cb of the trees. The Log y = A Log [(DBH)2·Ht] + B equation gives a fairly satisfactory regression coefficient (R2 > 0.9) for the woody compartments. For A. marina, it is the equation Log y = A Log Cb + B that is the best correlated for the estimation of less woody compartments (R2 = 0.826 to 0.847). As for R. mucronata, these are much more related to DBH. For trees of 8 - 10 m height, the aboveground biomass of the delta is higher (171 t·ha-1 for R. mucronata) than that of Puerto Rico, but quite comparable to that of Australia (110 t·ha-1 for A. marina). The first tools for estimating aboveground biomass are given for these two characteristic species of the Indo-Pacific Region and East Africa. Because of the low values of the regression coefficients for some allometric relationships obtained, precautions should be taken in case of extrapolation.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
The species composition and characteristics of mangrove flora in the world were reviewed and discussed. The results suggested that the world's mangrove plants have 84 species (including 12 varieties) in 24 genera ...The species composition and characteristics of mangrove flora in the world were reviewed and discussed. The results suggested that the world's mangrove plants have 84 species (including 12 varieties) in 24 genera and 16 families. Of which, true mangrove plants have 70 species (including 12 varieties) in 16 genera and 11 families, and semi-mangrove plants 14 species in eight genera and five families. The Eastern Group has 74 species (including 12 varieties) in 18 genera and 14 families, characterized by the genera Aegiceras, Osbornia, Aegialitis, Bruguiera, Ceriops, Kandelia, Scyphiphora and Nypa etc. The Western Group has only 10 species in six genera and five families, characterized by the endemic one-species family, Pelliceraceae, and the genus Laguncularia. The mangrove flora of China is composed of 26 species (including one variety) in 15 genera and 12 families, four of which are endemic. Hainan is most rich in mangrove species, making up about 96.2% of the Chinese total; Guangdong ranks second, making up about 42.3%. It has been demonstrated that Rhizophora stylosa was mistaken for R. mucronata in Taiwan by previous authors.展开更多
文摘This review examines the chemical compositions and bioactivities of mangrove plants belonging to the Rhizophoraceae family.The Rhizophoraceae family of true mangrove plants is the most common and is also widely distributed species.It consists of 24 species across four genera.Of the 24 species,12 species remain unexamined for their phytochemical constituents.There have been 268 metabolites reported from 16 species.The key phytochemical constituents identified across the family are the diterpenoids and triterpenoids.The major diterpenoids include pimaranes,beyeranes,kaurenes,dolabranes and labdanes whereas the significant triterpenoids are lupanes,dammaranes and oleananes.Disulphides,dolabranes and labdanes are considered to be the chemotaxonomic markers of the genera Bruguiera,Ceriops and Rhizophora respectively.
文摘Objective:To evaluate the antibacterial activity of foliar extracts of Rhizophora mucronnata(R. mucronata) against pathogens belonging to human origin and to identify the compound hitherto unprecedented in nature by GC-MS analysis.Methods:Soxhlet extraction method was used to get the corresponding extracts of ethanol,petroleum ether,acetone,methanol and ethyl acetate.The antimicrobial activities of the organic solvent extracts on the various test organisms using agar well diffusion technique were carried out.Ethyl acetate extract exhibited promising antimicrobial activity and hence minimum inhibitory concentration(MIC) was performed for the same.Column chromatography was done for partial purification of crude extract and fractions were analyzed by GC-MS.Results:A column chromatographic fractionation of the extracts and further UV visible and GS-MS analysis suggested the active principle compound were a mixture of squalene(19.19%),n-Hexadecanoic acid(6.59%),phytol(4.74%).2-cyclohexane-l- one, 4-hydroxy-3,5,(4.20%) and oleic acid(2.88%).Conclusions:The results are good enough to serve to transform the practice of research in this sub field across a range of different benefit streams that include drug development.By and large this type of structure analyses are most important as aids to more rational decision taking in safety models versus effectiveness.In general,structural data provide prima facie support for drug hypothesis.
文摘Studies on the corrosion behaviour of mild steel electrodes in inhibited hydrochloric acid are described. Conventional weight loss measurements show that a maximum concentration of 140 ppm of tannin from Rhizophora racemosa is required to achieve 72% corrosion inhibition. Similar concentration of tannin: H3PO4 in ratio 1:1 gave 61% inhibition efficiency, whereas efficiency obtained for phosphoric acid as inhibitor in the same environment was 55%. Corrosion rates obtained over six hours of exposure in 1M HCl solution at inhibitor concentrations of 140 ppm are 2 mA/cm2, 2.4 mA/cm2, 2.6 mA/cm2 and 6 mA/cm2 for tannin, tannin/H3PO4 and H3PO4-inhibited and uninhibited specimens respectively. Natural atmospheric exposure studies revealed that specimens treated in H3PO4 resisted corrosion for three weeks, while tannin treated specimens suffered corrosion attack after one week of exposure tests.
文摘This paper deals with the distribution pattern type,aggregative intensity,pattern scaleand dynamics of plant populations of Rhizophora stylosa community in Yingluo Bay of Guangxi.The measured results show that R.stylosa population is an aggregated distribution,while thepopulations of Kandelia candel,Bruguiera gymnorrhiza and Aegiceras corniculatum appear asrandom distribution.The plant population distribution pattern changes,along with the populationdevelopment and the succession of the community.
基金financed in part by a Grant-in-Aid for Scientific Research(No.23380094) from the Ministry of Education,Culture,Sports, Science and Technology,Japan
文摘Background： Progress of forest production in response to the environment requires a quantitative understanding of leaf area development. Therefore, it is necessary to investigate the dynamics of seasonal crown foliage in order to understand the productivity of mangroves, which play an important role in the subtropical and tropical coastlines of the world. Method： Crown foliage dynamics of the mangrove Rhizophora styloso were studies to reveal patterns of leaf recruitment, survival and seasonal leaf area growth. Results： Flushing of leaves occurred throughout the year, but both flushing and leaf area growth pattern of leaves varied with season. Maximum flushing occurred in summer, but leaf areas did not differ significantly with season. The half-expansion period is longer, and the intrinsic rate of increase was lower in winter. Summer flushed leaves grew faster at their initial stage and reached their maximum area over a shorter period of time. The difference in temperature and air vapor pressure deficit （VPD） between summer and winter contributed to the present dynamics of foliage patterns. The mean leaf longevity was estimated to be 13.1 month. The crown foliage area was almost stable throughout the year. Conclusions： Homeostatic control of the crown foliage area may be accompanied by the existence of ecophysiological mechanisms in R. stylosa. Integrating crown foliage dynamics into forest models represents an important step towards incorporating physiological mechanisms into the models for predicting growth responses to environmental changes and for understanding the complex responses of tree growth and litter production.
文摘Forty-three trees (23 Rhizophora mucronata and 20 Avicennia marina) were studied for the establishment of allometric relationships between the aboveground biomass “y” and the following dendrometric variables “x”: diameter at breast height DBH, (DBH)2 product Ht (where Ht is the total height), and the basal circumference Cb of the trees. The Log y = A Log [(DBH)2·Ht] + B equation gives a fairly satisfactory regression coefficient (R2 > 0.9) for the woody compartments. For A. marina, it is the equation Log y = A Log Cb + B that is the best correlated for the estimation of less woody compartments (R2 = 0.826 to 0.847). As for R. mucronata, these are much more related to DBH. For trees of 8 - 10 m height, the aboveground biomass of the delta is higher (171 t·ha-1 for R. mucronata) than that of Puerto Rico, but quite comparable to that of Australia (110 t·ha-1 for A. marina). The first tools for estimating aboveground biomass are given for these two characteristic species of the Indo-Pacific Region and East Africa. Because of the low values of the regression coefficients for some allometric relationships obtained, precautions should be taken in case of extrapolation.
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.
文摘The species composition and characteristics of mangrove flora in the world were reviewed and discussed. The results suggested that the world's mangrove plants have 84 species (including 12 varieties) in 24 genera and 16 families. Of which, true mangrove plants have 70 species (including 12 varieties) in 16 genera and 11 families, and semi-mangrove plants 14 species in eight genera and five families. The Eastern Group has 74 species (including 12 varieties) in 18 genera and 14 families, characterized by the genera Aegiceras, Osbornia, Aegialitis, Bruguiera, Ceriops, Kandelia, Scyphiphora and Nypa etc. The Western Group has only 10 species in six genera and five families, characterized by the endemic one-species family, Pelliceraceae, and the genus Laguncularia. The mangrove flora of China is composed of 26 species (including one variety) in 15 genera and 12 families, four of which are endemic. Hainan is most rich in mangrove species, making up about 96.2% of the Chinese total; Guangdong ranks second, making up about 42.3%. It has been demonstrated that Rhizophora stylosa was mistaken for R. mucronata in Taiwan by previous authors.
