Objective:To explore antibacterial activity and characterization of secondary metabolites isolated from mangrove plant Avicennia officinalis(A.officinalis).Methods:In the present study the leaf extracts of A.officinal...Objective:To explore antibacterial activity and characterization of secondary metabolites isolated from mangrove plant Avicennia officinalis(A.officinalis).Methods:In the present study the leaf extracts of A.officinalis were examined for its antibacterial potential using five different solvents against some reference strains of human pathogenic bacteria for the crude extract.Maximum activity was observed for ethyl acetate and hence different concentrations like 15μL,25μL,and 50μL of ethyl extracts was checked for its antibacterial activity.Partial purification of crude extract was carried by column chromatography and fractions were analyzed using gas chromatography-mass spectrometry(GC-MS) to identify compounds.Results:The crude ethyl acetate extracts of A.officinalis showed remarkable antibacterial activity with zones of inhibition of 13 mm against Eschericia coli(E.coli) and 11 mm against Staphylococcus aureus (S.aureus).Fraction 13(ethyl acetate:methanol= 8:2) as the most potent one against with the minimal inhibitory concentration of 30 mm against E.coli and 25 mm against S.aureus.The GCMS resultsof active column fraction(F13) revealed that the active principals were a mixture of hydroxy- 4 methoxybenzoic acid,diethyl phthalate,oleic acid.Conclusions:The leaf extracts with proven antibacterial effects can clearly be directed towards cancer treatment as to inhibiting cancer cell growth.The limited number of test organisms owes to a constraint of resource.So,the effect of strong bursts of leaf extracts on human pathogenic bacteria should further be tested on a wide range of test organisms.展开更多
A new acylated iridoid glucoside, namely, 2'-O-(5-phenyl-2E, 4E-pentadienoyl)- mussaenosidic acid, was isolated from the aerial parts of the mangrove plant Avicennia marina. The structure of the new compound was es...A new acylated iridoid glucoside, namely, 2'-O-(5-phenyl-2E, 4E-pentadienoyl)- mussaenosidic acid, was isolated from the aerial parts of the mangrove plant Avicennia marina. The structure of the new compound was established on the basis of various NMR spectroscopic analyses, including 2D NMR techniques (^1H-^1H COSY, HMQC, and HMBC) and HR-FAB-MS. This compound displayed moderate antioxidant activity.展开更多
A trial ofAvicennia officinalis L. with five different spacings was conducted in the newly accreted lands along the western coastline (Patuakhali district) of Bangladesh since 1993 to assess growth perform- ance and...A trial ofAvicennia officinalis L. with five different spacings was conducted in the newly accreted lands along the western coastline (Patuakhali district) of Bangladesh since 1993 to assess growth perform- ance and the effect of spacing on tree growth. Data on tree density, height, diameter, bole height, crown diameter were recorded and ana- lyzed when the stand was 19 years old. Mean height ranged from 12.89-13.52 m and diameter at breast height (dbh) from 26.57-32.16 cm in plots of different spacings. The mean annual height increment ranged from 0,67-0.71 m, mean annual diameter increment from 1.40-1.69 cm and wood volume from 6.02-10.04 m3.ha'l.al in different treatments. Significantly greater diameter (32.16 cm) and wood volume (10.04 m3.hal.a-1) were obtained with wider (2.13 m × 2.13 m) spacing than with closer spacings. But tree growth was unaffected by other spacings. Growth data were also recorded from other .4. officinalis plantations raised by Forest Department (FD) on different islands in Patuakhali and Bhola districts of Bangladesh. At these sites, mean annual height incre- ment ranged from 0.33-0.62 m, mean annual diameter increment from 0.72-1,37 cm and wood volume from 1.55-5.73 m3·ha-1·a·-1. The growth performance of A. offindicated that the newly aecreted lands along the western shoreline may be suitable for raising Avicennia planta- tions for the enrichment of coastal vegetation.展开更多
An outdoor experiment was set up to investigate the effects of used lubricating oil (5 L/m^2) on Aegiceras corniculatum Blanco. and Avicennia marina (Forsk) Vierh., two salt-excreting mangroves. A. marina was more...An outdoor experiment was set up to investigate the effects of used lubricating oil (5 L/m^2) on Aegiceras corniculatum Blanco. and Avicennia marina (Forsk) Vierh., two salt-excreting mangroves. A. marina was more sensitive to used lubricating oil than A. corniculatum and canopy-oiling resulted in more direct physical damage and stronger lethal effects than base-oiling. When treated with canopy-oiling, half of A. corniculatum plants survived for the whole treatment time (90 d); but, for A. marina, high mortality (83%) resulted from canopy-oiling within 3 weeks and no plants survived for 80 d. Base-oiling had no lethal effects on A. corniculatum plants even at the termination of this experiment, but 83% of A. marina plants died 80 d after treatment. Forty days after canopyoiling, 93% ofA. corniculatum leaves fell and no live leaves remained on A. marina plants. By the end of the experiment, base-oiling treatment resulted in about 45% ofA. corniculatum leaves falling, while all A. mar/na leaves and buds were burned to die. Lubricating oil resulted in physiological damage to A. corniculatum leaves, including decreases in chlorophyll and carotenoid contents, nitrate reductase, peroxidase and superoxide dismutase activities, and increases in malonaldehyde contents. For both species, oil pollution significantly reduced leaf, root, and total biomass, but did not significantly affect stem biomass. Oil pollution resulted in damage to the xylem vessels of fine roots but not to those of mediate roots.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
The fruits of Avicennia marina are widely used for both medicine and food in Guangxi of China.As a part of our continuous effort to search for bioactive molecules from the plant,the fruits of A.marina were investigate...The fruits of Avicennia marina are widely used for both medicine and food in Guangxi of China.As a part of our continuous effort to search for bioactive molecules from the plant,the fruits of A.marina were investigated,which has led to one new triterpenoid saponin(1)and 29 known compounds been isolated and their structures were established by using spectroscopic methods and comparing with literature data.The new triterpenoid saponin showed cytotoxicity against GSC3#and GSC-18# with the IC50 values were 12.21 and 5.53 μg/mL respectively,and most of the known compounds had significant antioxidant capacity with the IC_(50) values ranging from 0.36 to 13.07 μg/mL.展开更多
Mangroves are adapted to intertidal zones,which present extreme environmental conditions.WRKYs are among the most prominent transcription factors(TFs)in higher plants and act through various interconnected networks to...Mangroves are adapted to intertidal zones,which present extreme environmental conditions.WRKYs are among the most prominent transcription factors(TFs)in higher plants and act through various interconnected networks to regulate responses to multiple abiotic stressors.Here,based on omic data,we investigated the landscape and evolutionary patterns of WRKYs in the main mangrove genus Avicennia.We found that both the number and the proportion of TFs and WRKYs in Avicennia species exceeded their inland relatives,indicating a signifcant expansion of WRKYs in Avicennia.We identifed 109 WRKY genes in the representative species Avicennia marina.Comparative genomic analysis showed that two recent wholegenome duplication(WGD)events played a critical role in the expansion of WRKYs,and 88%of Avicennia marina WRKYs(AmWRKYs)have been retained following these WGDs.Applying comparative transcriptomics on roots under experimental salt gradients,we inferred that there is high divergence in the expression of WGD-retained AmWRKYs.Moreover,we found that the expression of 16 AmWRKYs was stable between freshwater and moderately saline water but increased when the trees were exposed to high salinity.In particular,14 duplicates were retained following the two recent WGD events,indicating potential neo-and sub-functionalization.We also found that WRKYs could interact with other upregulated genes involved in signalling pathways and natural antioxidant biosynthesis to enhance salt tolerance,contributing to the adaptation to intertidal zones.Our omic data of the WRKY family in A.marina broadens the understanding of how a TF family relates to the adaptive evolution of mangroves.展开更多
Objective:To evaluate the antioxidant and antimicrobial potential of different parts(leaf,stem and pneumatophore)of a mangrove plant Avicennia marina(Forsk.)Vierh(Avicenniaceae).Methods:The extraction was done by cold...Objective:To evaluate the antioxidant and antimicrobial potential of different parts(leaf,stem and pneumatophore)of a mangrove plant Avicennia marina(Forsk.)Vierh(Avicenniaceae).Methods:The extraction was done by cold percolation method using solvents of hexane,ethyl acetate,acetone,methanol and water.Total phenol and flavonoid content were measured by Folin-Ciocalteu’s reagent and aluminium chloride colorimetric method respectively.The antioxidant activity was evaluated using antioxidant assays of 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity,superoxide radical scavenging assay,2,2’-azino-bis-(3-ethyl)benzothiazoline-6-sulfonic acid,ferric reducing antioxidant power and reducing capacity assessment.The antibacterial activity was done by agar well diffusion method against four Gram-positive,four Gram-negative bacteria and four fungi.Results:Different antioxidant assays showed different levels of activity in different parts and different solvent extracts.Overall,acetone extract of stem showed the best antioxidant activity.The Gram-positive bacteria were more susceptible than Gram-negative bacteria and fungi.Conclusions:The results indicated extract of Avicennia marina can be used as a promising source of natural antioxidant.展开更多
Salt-tolerant gene, CSRG1, which was isolated from a kind of salt-tolerant mangroves, Avicennia marina, constructed the transgenic plasmid, pGAM189/CSRG1. CSRG1, GUS, Kmr and Hyg^r could be transferred into tobacco ge...Salt-tolerant gene, CSRG1, which was isolated from a kind of salt-tolerant mangroves, Avicennia marina, constructed the transgenic plasmid, pGAM189/CSRG1. CSRG1, GUS, Kmr and Hyg^r could be transferred into tobacco genome by the ameliorated leaf discs method of agro-bacterium-mediate transformation. Thirteen stable resistant lines were obtained when fifty transgenic explants were selected through 50 mg/L hygromycin and 150 mg/L kanamycin. Assessments of PCR amplification, Southern blot analysis and GUS histochemical staining showed that CSRG1 has been integrated into the genome of the eleven transgenic lines (frequency of transformation was 22%). Northern bolt analysis revealed that CSRG1 had expressed in transgenic lines. The assessments of salt-tolerant ability and photosyn-thetic rates indicated that the survival rate of the transgenic lines is 80%—90% and the transgenic lines could increase by 30%—40% in plant height, even when they were cultivated in MS medium containing 2% NaCl and the total seawater (salinity 24). It is supposed that the special physiologic metabolic pathway formed by the products of CSRG1 can really endow the tobacco plants with the high salt-tolerant ability, not only to Na^+ stress, but also to the comprehensive stress of various ions.展开更多
文摘Objective:To explore antibacterial activity and characterization of secondary metabolites isolated from mangrove plant Avicennia officinalis(A.officinalis).Methods:In the present study the leaf extracts of A.officinalis were examined for its antibacterial potential using five different solvents against some reference strains of human pathogenic bacteria for the crude extract.Maximum activity was observed for ethyl acetate and hence different concentrations like 15μL,25μL,and 50μL of ethyl extracts was checked for its antibacterial activity.Partial purification of crude extract was carried by column chromatography and fractions were analyzed using gas chromatography-mass spectrometry(GC-MS) to identify compounds.Results:The crude ethyl acetate extracts of A.officinalis showed remarkable antibacterial activity with zones of inhibition of 13 mm against Eschericia coli(E.coli) and 11 mm against Staphylococcus aureus (S.aureus).Fraction 13(ethyl acetate:methanol= 8:2) as the most potent one against with the minimal inhibitory concentration of 30 mm against E.coli and 25 mm against S.aureus.The GCMS resultsof active column fraction(F13) revealed that the active principals were a mixture of hydroxy- 4 methoxybenzoic acid,diethyl phthalate,oleic acid.Conclusions:The leaf extracts with proven antibacterial effects can clearly be directed towards cancer treatment as to inhibiting cancer cell growth.The limited number of test organisms owes to a constraint of resource.So,the effect of strong bursts of leaf extracts on human pathogenic bacteria should further be tested on a wide range of test organisms.
基金supported by the program of"Bairen Jihua"from the Chinese Academy of Sciences,by the National Natural Science Foundation of China(No.30530080)the innovation program of the Institute of 0ceanology,Chinese Academy of Sciences(L79032432).
文摘A new acylated iridoid glucoside, namely, 2'-O-(5-phenyl-2E, 4E-pentadienoyl)- mussaenosidic acid, was isolated from the aerial parts of the mangrove plant Avicennia marina. The structure of the new compound was established on the basis of various NMR spectroscopic analyses, including 2D NMR techniques (^1H-^1H COSY, HMQC, and HMBC) and HR-FAB-MS. This compound displayed moderate antioxidant activity.
文摘A trial ofAvicennia officinalis L. with five different spacings was conducted in the newly accreted lands along the western coastline (Patuakhali district) of Bangladesh since 1993 to assess growth perform- ance and the effect of spacing on tree growth. Data on tree density, height, diameter, bole height, crown diameter were recorded and ana- lyzed when the stand was 19 years old. Mean height ranged from 12.89-13.52 m and diameter at breast height (dbh) from 26.57-32.16 cm in plots of different spacings. The mean annual height increment ranged from 0,67-0.71 m, mean annual diameter increment from 1.40-1.69 cm and wood volume from 6.02-10.04 m3.ha'l.al in different treatments. Significantly greater diameter (32.16 cm) and wood volume (10.04 m3.hal.a-1) were obtained with wider (2.13 m × 2.13 m) spacing than with closer spacings. But tree growth was unaffected by other spacings. Growth data were also recorded from other .4. officinalis plantations raised by Forest Department (FD) on different islands in Patuakhali and Bhola districts of Bangladesh. At these sites, mean annual height incre- ment ranged from 0.33-0.62 m, mean annual diameter increment from 0.72-1,37 cm and wood volume from 1.55-5.73 m3·ha-1·a·-1. The growth performance of A. offindicated that the newly aecreted lands along the western shoreline may be suitable for raising Avicennia planta- tions for the enrichment of coastal vegetation.
基金Project supported by the Program for New Century Excellent Talents in University(NCET)Environment and Conservation Fund of the HKSAR(No.9210007)
文摘An outdoor experiment was set up to investigate the effects of used lubricating oil (5 L/m^2) on Aegiceras corniculatum Blanco. and Avicennia marina (Forsk) Vierh., two salt-excreting mangroves. A. marina was more sensitive to used lubricating oil than A. corniculatum and canopy-oiling resulted in more direct physical damage and stronger lethal effects than base-oiling. When treated with canopy-oiling, half of A. corniculatum plants survived for the whole treatment time (90 d); but, for A. marina, high mortality (83%) resulted from canopy-oiling within 3 weeks and no plants survived for 80 d. Base-oiling had no lethal effects on A. corniculatum plants even at the termination of this experiment, but 83% of A. marina plants died 80 d after treatment. Forty days after canopyoiling, 93% ofA. corniculatum leaves fell and no live leaves remained on A. marina plants. By the end of the experiment, base-oiling treatment resulted in about 45% ofA. corniculatum leaves falling, while all A. mar/na leaves and buds were burned to die. Lubricating oil resulted in physiological damage to A. corniculatum leaves, including decreases in chlorophyll and carotenoid contents, nitrate reductase, peroxidase and superoxide dismutase activities, and increases in malonaldehyde contents. For both species, oil pollution significantly reduced leaf, root, and total biomass, but did not significantly affect stem biomass. Oil pollution resulted in damage to the xylem vessels of fine roots but not to those of mediate roots.
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.
基金The authors are grateful to the Natural Science Foundation of China(31770388,81225024)the "Ten Thousand Plan",a National High-level Talents Special Support Plan for partial financial support.
文摘The fruits of Avicennia marina are widely used for both medicine and food in Guangxi of China.As a part of our continuous effort to search for bioactive molecules from the plant,the fruits of A.marina were investigated,which has led to one new triterpenoid saponin(1)and 29 known compounds been isolated and their structures were established by using spectroscopic methods and comparing with literature data.The new triterpenoid saponin showed cytotoxicity against GSC3#and GSC-18# with the IC50 values were 12.21 and 5.53 μg/mL respectively,and most of the known compounds had significant antioxidant capacity with the IC_(50) values ranging from 0.36 to 13.07 μg/mL.
基金We thank Qipian Chen,Zuyao Liu and Min Liu for technical support.We thank the editors and reviewers for their helpful contributions.The project was supported by the National Natural Science Foundation of China(32170230,31971540 and 31830005)the Guangdong Basic and Applied Basic Research Foundation(2023B1515020083)the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(311021006).
文摘Mangroves are adapted to intertidal zones,which present extreme environmental conditions.WRKYs are among the most prominent transcription factors(TFs)in higher plants and act through various interconnected networks to regulate responses to multiple abiotic stressors.Here,based on omic data,we investigated the landscape and evolutionary patterns of WRKYs in the main mangrove genus Avicennia.We found that both the number and the proportion of TFs and WRKYs in Avicennia species exceeded their inland relatives,indicating a signifcant expansion of WRKYs in Avicennia.We identifed 109 WRKY genes in the representative species Avicennia marina.Comparative genomic analysis showed that two recent wholegenome duplication(WGD)events played a critical role in the expansion of WRKYs,and 88%of Avicennia marina WRKYs(AmWRKYs)have been retained following these WGDs.Applying comparative transcriptomics on roots under experimental salt gradients,we inferred that there is high divergence in the expression of WGD-retained AmWRKYs.Moreover,we found that the expression of 16 AmWRKYs was stable between freshwater and moderately saline water but increased when the trees were exposed to high salinity.In particular,14 duplicates were retained following the two recent WGD events,indicating potential neo-and sub-functionalization.We also found that WRKYs could interact with other upregulated genes involved in signalling pathways and natural antioxidant biosynthesis to enhance salt tolerance,contributing to the adaptation to intertidal zones.Our omic data of the WRKY family in A.marina broadens the understanding of how a TF family relates to the adaptive evolution of mangroves.
文摘Objective:To evaluate the antioxidant and antimicrobial potential of different parts(leaf,stem and pneumatophore)of a mangrove plant Avicennia marina(Forsk.)Vierh(Avicenniaceae).Methods:The extraction was done by cold percolation method using solvents of hexane,ethyl acetate,acetone,methanol and water.Total phenol and flavonoid content were measured by Folin-Ciocalteu’s reagent and aluminium chloride colorimetric method respectively.The antioxidant activity was evaluated using antioxidant assays of 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity,superoxide radical scavenging assay,2,2’-azino-bis-(3-ethyl)benzothiazoline-6-sulfonic acid,ferric reducing antioxidant power and reducing capacity assessment.The antibacterial activity was done by agar well diffusion method against four Gram-positive,four Gram-negative bacteria and four fungi.Results:Different antioxidant assays showed different levels of activity in different parts and different solvent extracts.Overall,acetone extract of stem showed the best antioxidant activity.The Gram-positive bacteria were more susceptible than Gram-negative bacteria and fungi.Conclusions:The results indicated extract of Avicennia marina can be used as a promising source of natural antioxidant.
文摘Salt-tolerant gene, CSRG1, which was isolated from a kind of salt-tolerant mangroves, Avicennia marina, constructed the transgenic plasmid, pGAM189/CSRG1. CSRG1, GUS, Kmr and Hyg^r could be transferred into tobacco genome by the ameliorated leaf discs method of agro-bacterium-mediate transformation. Thirteen stable resistant lines were obtained when fifty transgenic explants were selected through 50 mg/L hygromycin and 150 mg/L kanamycin. Assessments of PCR amplification, Southern blot analysis and GUS histochemical staining showed that CSRG1 has been integrated into the genome of the eleven transgenic lines (frequency of transformation was 22%). Northern bolt analysis revealed that CSRG1 had expressed in transgenic lines. The assessments of salt-tolerant ability and photosyn-thetic rates indicated that the survival rate of the transgenic lines is 80%—90% and the transgenic lines could increase by 30%—40% in plant height, even when they were cultivated in MS medium containing 2% NaCl and the total seawater (salinity 24). It is supposed that the special physiologic metabolic pathway formed by the products of CSRG1 can really endow the tobacco plants with the high salt-tolerant ability, not only to Na^+ stress, but also to the comprehensive stress of various ions.