IN VITRO INHIBITORY ACTIVITY OF MEDICINAL PLANTS AGAINST PHOMOPSIS AZADIRACHTAE, THE INCITANT DIE BACK DISEASE OF NEEM

Objectives: Plant diseases extend a threat to the global production of herbal medicines. Safer plant protection strategies are in need to meet the demands from the pharmaceutical industry. Neem is a tree with great medicinal values, which is being infected by Phomopsis azadirachtae (PA), causing die back disease. The resulting massive destruction of the tree demands optimum disease management methods and thus, the objective of the present study was to evaluate the inhibitory potential of some plant extracts against the growth of PA.Methods: In this study, we investigate the in vitro antifungal activity of ether: chloroform (1:1), ethyl acetate, acetone and ethanol extracts from different parts (leaves and roots) of five plant species viz., Ocimum tenuiflorium, Centella asiatica, Solanum nigrum, Apium graveolens and Besella alba against the growth of PA.Results: All the 40 crude extracts (at concentration of 1000 μg/ml), were active against PA. Among them, the ethanol and ethyl acetate extracts proved optimum with antifungal activity ranging from 65-95% and minimum inhibitory concentration (MIC) values from 75-200 μg/ml. The antifungal activity of the extracts was in the order: ethanol>ethyl acetate>acetone>ether: chloroform (1:1). Also, noteworthy results were observed in all the extracts tested against the spore germination of PA, with concentration and time-dependent kinetics.Conclusion: The results prove promising in order to develop new antifungal agents against the growth and spread of PA.Â

Development of bioconjugated nano-molecules against targeted microbial pathogens for enhanced bactericidal activity

The study reports development of bio-conjugated nano-molecules (BCM's) for enhanced antibacterial activity against targeted pathogens of global concern. The conjugation was achieved with biomolecular interaction of silver clusters with 3-Dichloro-5, 6-dicyano-1, 4-benzoquinone (DDQ) which was purified and characterized with TLC which displayed prominent band at R-f 0.5 and HPLC analysis displayed chromatographic peak eluting at (t(R)) 6-8 min. The LC-MS analysis displayed single major peak at t(R) = 4.610 corresponding to molecular ion peak at m/z = 227.19. The developed BCM molecule was determined with UV-Visible spectroscopy which displayed the absorbance peaks of conjugated molecules with shoulder peak observed and morphological characteristics were well defined with TEM analysis which showed cluster formation. The size ranged from 20 to 80 nm in size with majority of the BCM displaying spherical in size. The process of bio-conjugation was further studied with FTIR analysis which corresponded with different vibrational stretches owing to the presence of amide, carbonyl alkynes, nitriles and carboxylic acid groups. The presence of functional moieties was also studied using H-1 and C-13 NMR spectra. The crystalline characteristics was confirmed with XRD analysis which displayed Bragg's intensities along with additional peaks occurring at 2 theta angle corresponds to (111), (200), (220), (311) face centric cube of silver planes. The antibacterial activity of BCM's was profound against all the test pathogen which was validated and compared with standard antibiotics. Among the test pathogens, highest activity was conferred against Staphylococcus epidermidis (MTCC 435) with 29 mm. The minimal inhibition concentration of BCM's was in the range of 0.97-3.12 mu g/ml. The results of MIC were in accordance with well diffusion assay indicating the Gram + ve test pathogen Staphylococcus epidermidis to be the most sensitive. In addition, the broth dilution assay resulted in decrease in the optical density measured at 600 nm against the increase in the concentration of BCM's. The outcome of the present investigation revealed the role of bio-conjugation chemistry to increase fold activity against pathogens which can act as alternative tool to combat drug resistant menace across the globe

EVALUATION OF BANANA (MUSA SP. VAR. NANJANGUD RASA BALE) FLOWER AND PSEUDOSTEM EXTRACTS ON ANTIMICROBIAL, CYTOTOXICITY AND THROMBOLYTIC ACTIVITIES

Objectives: The present study is centered on potential utilization of banana flower (FB) and pseudostem (PB), as a source of antimicrobial, cytotoxic and thrombolytic contributor, which otherwise is discarded as waste or burnt.Methods: FB and PB, the by-products of banana cultivation were extracted sequentially using various solvents viz., ether: chloroform (1:1), ethyl acetate, acetone, methanol, ethanol and water. In vitro antimicrobial activity of the extracts was tested against six bacterial strains using standard disc diffusion method and the minimal inhibitory concentration (MIC) was performed by microdilution method. Further to validate the safe consumption, extracts were assessed for toxicity evaluation in cell culture against 3T3-L1 cell line (obtained from adipose tissues) using MTT assay.  Also, the thrombolytic activity was performed by clot disruption method.Results: Phytochemical analysis demonstrated that FB and PB were a rich source of polyphenols (saponins, terpenoids, flavonoids, coumarins), cardiac glycosides and steroids. Extracts possessed antimicrobial activities against all the microorganisms tested, with MIC values in the range between 1.2 to 2.5 mg/ml. The investigation on thrombolytic activity by the aqueous extracts of FB (18%) and PB (13%) expressed a significant percentage of clot lysis with reference to Streptokinase (64%). Also, all the extracts of FB and PB exhibited no cytotoxic effect against 3T3L1 cell line.Conclusion: The present work demonstrates the antimicrobial, cytotoxic and thrombolytic activities of FB and PB extracts. The activities exhibited could be the basis for their alleged health promoting abilities and serve as new source of natural nutraceutical with potential applications.Â

IMPACT OF ACTIVE COMPOUNDS ISOLATED FROM BANANA (MUSA SP. VAR. NANJANGUD RASABALE) FLOWER AND PSEUDOSTEM TOWARDS CYTOPROTECTIVE AND DNA PROTECTION ACTIVITIES

Objective: The present study was designed to evaluate for cytoprotective and DNA protective properties of the compounds isolated from ethanol extract of banana flower (EF) and ethanol extract of banana pseudostem (EE).Methods: The four active compounds viz., umbelliferone (C1) andlupeol (C2) from EF and stigmasterol (C3) and β-sitosterol (C4) from EE were isolated by activity-guided repeated fractionation through silica gel column chromatography. The isolated compounds were evaluated for cytoprotective on erythrocytes and pTZ57R/T plasmid DNA protection against hydroxyl radicals.Results: The study revealed that the compounds (C1-C4) at a concentration of 1 mg/ml exhibited 90% protection on erythrocytes membrane oxidation and also protect the pTZ57R/T plasmid DNA damage induced by hydroxyl radicals.Conclusion: These results endorse an insight for a strong chemical basis to the alleged beneï¬cial role of EF and EE in reducing oxidative stress conditions.Â

Serine protease from Indian Cobra venom: its anticoagulant property and effect on human fibrinogen

An unusual low molecular weight serine protease (NnP28) has been purified from Indian Cobra (Naja naja) venom from the western region of the Indian sub-continent. We reported the purification and characterization of low molecular NnP28, emphasizing its role on human fibrinogen and anticoagulant property. NnP28 was purified using gel filtration column chromatography followed by ion exchange chromatography. Protein gel electrophoresis revealed its molecular weight approximate to 28 kDa. The exact molecular mass of NnP28 was found to be 27.12 kDa by mass spectrometry, hydrolyzing casein specifically, inhibited by PMSF suggesting it has a serine protease. NnP28 prolonged the clotting time of re-calcified human citrated plasma and activated partial thromboplastin time (APTT) exhibiting anticoagulant property. NnP28 exhibited fibrinogenolytic activity. Thus, the present study demonstrates the presence of unusual low molecular weight serine protease, emphasizing its importance of region-specific Indian cobra species

Biomimetic synthesis of silver nanoparticles using endosymbiotic bacterium inhabiting euphorbia hirtal. And their bactericidal potential

The present investigation aims to evaluate biomimetic synthesis of silver nanoparticles using endophytic bacterium EH 419 inhabiting Euphorbia hirta L. The synthesized nanoparticles were initially confirmed with change in color from the reaction mixture to brown indicating the synthesis of nanoparticles. Further confirmation was achieved with the characteristic absorption peak at 440 nm using UV-Visible spectroscopy. The synthesized silver nanoparticles were subjected to biophysical characterization using hyphenated techniques. The possible role of biomolecules in mediating the synthesis was depicted with FTIR analysis. Further crystalline nature of synthesized nanoparticles was confirmed using X-ray diffraction (XRD) with prominent diffraction peaks at 2θ which can be indexed to the (111), (200), (220), and (311) reflections of face centered cubic structure (fcc) of metallic silver. Transmission electron microscopy (TEM) revealed morphological characteristics of synthesized silver nanoparticles to be polydisperse in nature with size ranging from 10 to 60 nm and different morphological characteristics such as spherical, oval, hexagonal, and cubic shapes. Further silver nanoparticles exhibited bactericidal activity against panel of significant pathogenic bacteria among which Pseudomonas aeruginosa was most sensitive compared to other pathogens. To the best of our knowledge, present study forms first report of bacterial endophyte inhabiting Euphorbia hirta L. in mediating synthesizing silver nanoparticle

Endogenic mediated synthesis of gold nanoparticles bearing bactericidal activity

The present investigation aimed to synthesize gold nanoparticles using Pseudomonas fluorescens 417 inhabiting Coffea arabica L. Biologically synthesized gold nanoparticles were polydispersed in nature and characterized using hyphenated techniques such as UV-visible spectrophotometry, which ascertained characteristic peaks between 450nm and 650nm. Fourier transform infrared analysis predicted the functional groups present in the cell-free supernatant that mediated the synthesis and stabilization of gold nanoparticles. The crystalline nature of the gold nanoparticles was analyzed with X-ray diffraction techniques that displayed the Bragg's diffraction intensity. Transmission electron microscopy revealed the size of nanoparticles ranging from 5nm to 50nm, with most of them bearing a spherical shape. The study also revealed the bactericidal activity of synthesized nanoparticles against a panel of clinically significant pathogens. Maximum activity was observed against Pseudomonas aeroginosa followed by Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Klebsiella pneumoniae. The results obtained in the present investigation are promising for ecofriendly approaches for synthesis of gold nanoparticles bearing bactericidal activity that can act as an alternative to combat drug-resistant pathogens

Hydromagnetic Flow of Heat and Mass Transfer in a Nano Williamson Fluid Past a Vertical Plate With Thermal and Momentum Slip Effects: Numerical Study

In this article, the study of heat, momentum and mass (species) transfer in an electro-conductive polymer on the external surface of a vertical plate. The effects of Brownian motion and thermophoresis are incorporated in the model in the presence of both heat and nanoparticle mass transfer convective conditions. The Williamson viscoelastic model is employed which is representative of certain industrial polymers. The non-dimensional, transformed boundary layer equations for momentum and energy are solved with the second order accurate implicit Keller box finite difference method under appropriate boundary conditions. The influence of Weissenberg number, magnetic body force parameter, thermal slip parameter, hydrodynamic slip parameter, stream wise variable and Prandtl number on thermo fluid characteristics are presented graphically and discussed. A weak elevation in temperature accompanies increasing Weissenberg number whereas a significant acceleration in the flow is computed near the plate surface. Rate of heat transfer is reduced with increases the Weissenberg number. The study is relevant to enrobing processes for electric-conductive nano-materials, of potential use in aerospace, smart coating transport phenomena and other industries

Bioconjugated nano-bactericidal complex for potent activity against human and phytopathogens with concern of global drug resistant crisis

The present study emphasizes the need for novel antimicrobial agents to combat the global drug resistant crisis. The development of novel nanomaterials is reported to be of the alternative tool to combat drug resistant pathogens. In present investigation, bioconjugated nano-complex was developed from secondary metabolite secreted from endosymbiont. The endosymbiont capable of secreting antimicrobial metabolite was subjected to fermentation and the culture supernatant was assessed for purification of antimicrobial metabolite via bio-assay guided fraction techniques such as thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and column chromatography. The metabolite was characterized as 2,4-Diacetylphloroglucinol (2,4 DAPG) which was used to develop bioconjugated nano-complex by treating with 1 mM silver nitrate under optimized conditions. The purified metabolite 2,4 DAPG reduced silver nitrate to form bioconjugated nano-complex to form association with silver nanoparticles. The oxidized form of DAPG consists of four hard ligands that can conjugate on to the surface of silver nanoparticles cluster. The bioconjugation was confirmed with UV–visible spectroscopy which displayed the shift and shoulder peak in the absorbance spectra. This biomolecular interaction was further determined by the Fourier-transform spectroscopy (FTIR) and nuclear magnetic resonance (NMR) analyses which displayed different signals ascertaining the molecular binding of 2,4,DAPG with silver nanoparticles. The transmission electron microscopy (TEM) analysis revealed the cluster formation due to bioconjugation. The XRD analysis revealed the crystalline nature of nano-complex with the characteristic peaks indexed to Bragg's reflection occurring at 2θ angle which indicated the (111), (200), (220) and (311) planes. The activity of bioconjugated nano-complex was tested against 12 significant human and phytopathogens. Among all the test pathogens, Shigella flexneri (MTCC 1457) was the most sensitive organisms with 38.33 ± 0.33 zone of inhibition. The results obtained in the present investigation attribute development of nano-complex as one of the effective tools against multi-drug resistant infections across the globe