Cytotoxic (A549) and antimicrobial effects of Methylobacterium sp.isolate (ERI-135) from Nilgiris forest soil,India

Objective:To assess the antimicrobial and cytotoxic effects of Methylobacterium sp.isolated from soil sample of Doddabetta forest,Nilgiris,Western Ghats of Tamil Nadu.Methods:Isolation of Methylobacterium was performed from soils by serial dilution plate technique.The strain was grown in modified nutrient gulucose agar(MNGA)medium to study the morphology and biochemical characteristics.Methylobacterium sp.was screened for its antimicrobial activity against pathogenic bacteria and fungi.The strain was subjected to 16S rRNA analysis and was identified as Methylohacterium sp.The nucleotide sequence of the 16S rRNA gene of the isolate exhibited close similarity with other Methylobacterium sp.and has been submitted to Genbank.The antibacterial substances were extracted using chloroform and ethyl acetate from MNGA medium in which ERI-135 had grown for 5 d at 30℃.Cytotoxic effect was also studied.GC-MS analysis was carried out.The antimicrobial activity was assessed using broth micro dilution technique.Results:Ethyl acetate extract showed activity against bacteria such as Bacillus subtilis,Klebsiella pneumoniae(K.pneumoniae),Pseudomonas aeruginosa,Salmonella typkimurium,Shigella flexneri,Enterobacter aerogenes,Staphylococcus aureu and Staphylococcus epidermidis(S.epidermidis)and fungi such as,Candida albicans and Trichophyton rubrum.The lowest minimum inhibitory concentrations were:250μg/mL against 5.epidermidis and 250μg/mL against K.pneumonia.The isolate had the ability to produce enzymes such as protease.The exyract showed cytotoxic effect in human adenocarcinoma cancer cell line(A549).GC-MS analysis showed the presence of isovaleric acid(3.64%),2-Methylbulanoic acid(5.03%),isobutyramide(5.05%),N,Noimethylformamide-di-t-butylacetal(9.79%),benzeneacetamide(15.56%),octyl butyl phthalate(3.59%)and diisooctyl phthalate(5.79)in the extract.Conclusions:Methylobaeterium sp.(ERI-135)showed promising antibacterial and cytotoxic activity.This is the first report in the antimicrobial and cytotoxic effect of Methylobaeterium sp.

Antibacterial effect of Allium sativum cloves and Zingiber officinale rhizomes against multiple-drug resistant clinical pathogens

Objective:To evaluate the antibacterial properties ot Allium sativum(garlic) cloves and Zingiber officinale(ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection.Methods:The cloves of garlic and rhizomes of ginger were extracted with 95%(v/v) ethanol.The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens.Results:Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates.All the bacterial isolates were susceptible to crude extracts of both plants extracts.Except Enterobacter sp.and Klebsiella sp.,all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger.The highest inhibition zone was observed with garlic(19.4S mm) against Pseudomonas aeruginosa(P.aeruginosa).The minimal inhibitory concentration was as low as 67.00 μg/mL against P.aeruginosa.Conclusions:Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.

Characterization and phylogenetic analysis of novel polyene type antimicrobial metabolite producing actinomycetes from marine sediments:Bay of Bengal India

Objective:To isolate and indentify the promising antimicrobial metabolite producing Streptomyces strains from marine sediment samples from Andraprudesh coast of India.Methods:Antagonistic aetinomycetes were isolated by starch casein agar medium and modified nutrient agar medium with 1%glucose used as a base for primary screening.Significant antimicrobial metabolite producing strains were selected and identified by using biochemical and 16S rDNA level.Minimum inhibitory concentrations of the organic extracts were done by using broth micro dilution method.Results:Among the 210 actinomyeetes,64.3%exhibited activity against Gram positive bacteria,48.5%showed activity towards Cram negative bacteria,38.8%exhibited both Cram positive and negative bacteria and 80.85%isolates revealed significant antifungal activity.However,five isolates AP-5,AP-18,AP-41 and AP-70 showed significant antimicrobial activity.The analysis of cell wall hydrolysates showed the presence of LL-diaminopimelic acid and glycine in all the isolates.Sequencing analysis indicated that the isolates shared 98.5%-99.8%sequence identity to the 16S rDNA gene sequences of the Streptomyces taxons.The antimicrobial substances were extracted using hexane and ethyl acetate from spent medium in which strains were cultivated at 30X for five days.The antimicrobial activity was assessed using broth micro dilution technique.Each of the culture extracts from these five strains showed a typical polyenelike property.The lowest minimum inhibitory concentrations of ethyl acetate extracts against Escherichia coli and Cumularia lunula were 67.5 and 125.0μg/mL,respectively.Conclusions:It can be concluded that hexane and ethyl acetate soluble extracellular products of novel isolates are effective against pathogenic bacteria and fungi.

Trigonelline protects the cardiocyte from hydrogen peroxide induced apoptosis in H9c2 cells

Objective:To elucidate the key parameters associated with hydrogen peroxide induced oxidative stress and investigates the mechanism of trigonelline(TG)for reducing the H_2O_2induced toxicity in H9c2 cells.Methods:Cytotoxicity and antioxidant activity of TG was assessed by EZ-CYTOX kit.RNA extraction and cDNA synthesized according to the kit manufacture protocol.Apoptosis was measured by the Flowcytometry,general PCR and qPCR.Results:It was found that the TG significantly rescued the morphology of the H9c2 cells.Treatment of cells with TG attenuated H_2O_2 induced cell deaths and improved the antioxidant activity.In addition,TG regulated the apoptotic gene caspase-3,caspase-9 and anti-apoptotic gene Bcl-2.Bcl-XL during H_2O_2 induced oxidative stress in H9c2 cells.These results were comparable with quercetin treatment.For evident,flow cytometer results also confirmed the TG significantly reduced the H_2O_2 induced necrosis and apoptosis in H9c2 cells.However,further increment of TG concentration against H_2O_2 could induce the necrosis and apoptosis along with H_2O_2.Conclusions:It is suggested that less than 125μM of TG could protect the cells from H_2O_2 induced cell damage by down regulating the caspases and up regulating the Bcl-2 and Bcl-XL expression.Therefore,we suggest the trigonelline could be useful for treatment of oxidative stress mediated cardiovascular diseases in future.

Antibacterial and antioxidant activities of Musa sp.leaf extracts against multidrug resistant clinical pathogens causing nosocomial infection

Objective:To investigate different Musa sp.leave extracts of hexane,ethyl acetate and methanol were evaluated for antibacterial activity against multi-drug resistant pathogens causing nosocomial infection by agar well diffusion method and also antioxidant activities.Methods:The four different Musa species leaves were extracted with hexane,ethyl acetate and methanol.Antibacterial susceptibility test,minimum inhibitory concentration and minimum inhibitory bacterial concentration were determined by agar well diffusion method.Total phenolic content and in vitro antioxidant activity was determined.Results:All the Musa sp.extracts showed moderate antibacterial activities expect Musa paradisiaca with the inhibition zone ranging from 8.0 to 18.6 mm.Among four species ethyl acetate extracts of Musa paradisiaca showed highest activity against tested pathogens particularly E.coli,P.aeruginosa and Citrobacter sp.The minimum inhibitory concentrations were within the value of 15.63-250μg/ml.and minimum bactericidal concentrations were ranging from 31.25-250μg/mL.Antioxidant activity of Musa acuminate exhibited maximum activity among other three Musa species.Conclusions:The present study concluded that among the different Musa species,Musa paradisiaca displayed efficient antibacterial activity followed by Musa acuminata against multidrug resistant nosocomial infection causing pathogens.Further,an extensive study is needed to identify the bioactive compounds,mode of action and toxic effect in.vivo of Musa sp.

Identification and Determination of Phenolic Compounds in Rapeseed Meals (Brassica napus L.)

This study aimed in the identification and quantification of phenolic compounds in different four varieties of rapeseeds (Brassica napus L.) using LC-MS and HPLC. LC-MS analysis guided to identify 12 phenolic compounds including sinapine, sinapine(4-O-8')guaiacyl, feruloyl choline(4-O-8') guaiacyl, kaempferol-3-O-sinapoyl-sophoroside-7-O-glucoside, kaempferol-3-O-β-sophoroside, cyclic spermidine-alkaloid, feruloyl choline(5-8')guaiacyl, kaempferol-sinapoyl-trihexoside,1,2-di- O-sinapoyl-gentiobiose, 1,2-di-O-sinapoyl-glucose, feruloyl choline(4-O-8')guaiacyl-di-sinapoyl, and sinapine(4-O-8')guaiacyl-di-sinapoyl, respectively. Total phenolic compounds in rapeseed meals were ranged from 38.50 (2012 “Sunmang”) to 63.95 mg/g dry weight (DW) (2014 Jeju local cultivar). Main phenolic compositions were cyclic spermidine-alkaloid, kaempferol, feruloyl choline, and sinapine. Sinapine was predominant compound among all the samples ranged from 29.74 to 52.24 mg/g DW (mean 79% of total phenolic contents). This study provided the information for the variation of phenolic compounds between the varieties of rapeseeds and the cultivation periods. Furthermore, this information can be developed for bio-energy industry as a reducer of the cost of the bio-energy products.