Antibacterial activity and characterization of secondary metabolites isolated from mangrove plant Avicennia officinalis

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.

Characterization of cytotoxic compound from mangrove derived fungi Irpex hydnoides VB4

Objective:To investigate the cytotoxic activity of endophytic fungi isolated from mangrove fungi.Methods:In the present study the DNA was isolated and the ITS region of 5.8s rRNA was amplified using specific primers ITS 1 and ITS4 and sequence was determined using automated sequencers.Blast search sequence similarity was found against the existing non redundant nucleotide sequence database thus,identified as Aspergilus flavus,Hyporcaea lixii,Aspergillus niger,Eutorium amstelodami,Irpex hydnoides and Neurospora crassa.Among the seven isolates, one fungi Irpex hydnoides was selected for further studies.The fungi were grown in sabouraud broth for five days and filtrate were separated and subjected to ethyl acetate for further studies. Results:Nearly half(49.25%) of the extracts showed activity(IC_(50) of 125 μ g/mL).These values were within the cutoff point of the National Cancer Institute criteria for cytotoxicity(IC_(50)<20 μ g/mL) in the screening of crude plant extracts.The GC MS analysis revealed that the active principals might be Tetradecane(6.26%) with the RT 8.606.Conclusions:It is clear from the present study that mangrove fungi with bioactive metabolites can be expected to provide high quality biological material for high throughout biochemical,anti cancer screening programmes.The results help us conclude that me potential of using metabolic engineering and post genomic approaches to isolate more novel bioactive compounds and to make their possible commercial application is not far off.

Isolation and characterization of secondary metabolites from the mangrove plant Rhizophora mucronata

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.

红树林真菌Hypocrea lixii VB1的抗癌及抗菌活性(英文)

AIM:Mangrove is one of the oldest living tree species and its leaves are among the most extensively studied botanicals in use today.Scientific research throughout the world has found evidence to support the fact that its foliar extracts have great potential against human microbial pathogens.This study highlights the isolation of foliar fungi from Rhizophora mucronata,Avicenna officialis and Avicenna marina.METHOD:It was isolated in Sabouroud's Dextrose Agar and mass cultivation was done in Sabouroud's Dex-trose broth.RESULTS:The ethyl acetate extract showed maximum antibacterial activity which inturn checked for different concentra-tion against bacterial pathogens and anticancer activity for Hep2 and MCF7 cell line in vitro.The DNA was isolated from the fungi and the ITS region of 5.8 s RNA was sequenced and assigned to new species as they are separated from the type strains phylogenetic neighbors by sequence similarities.CONCLUSION:This preliminary screening of fungal endophytes revealed their potential to yield potent bioactive compounds for drug discovery programmes.