EXTRACTION, BIOACTIVITIES, PHYTOCHEMICAL INVESTIGATION AND IN-VIVO TOXICITY STUDIES OF MESUA FERREA L. STAMENS

Objective: To investigate in-vitro antibacterial and free radical scavenging potentials of Mesua ferrea L. stamens which are used in traditional medicinal preparations along with their phytochemical investigation and in-vivo toxicity studiesMethods: Various extracts of M. ferrea stamens were prepared by kinetic maceration method using four organic solvents. Potent antibacterial n-hexane extract of stamens was selected in the preliminary screening for antibacterial activity which was performed by an agar diffusion method for further studies. Quantification of antibacterial activity of n-hexane extract was carried out using broth microdilution method as per CLSI guidelines. Phytochemical investigations of the same extract were performed using qualitative tests for the detection of various phytochemical groups and Libermann-Burchard colorimetric assay for determination of total terpenoid content. In-vivo safety of the extract was determined by acute oral toxicity studies in mice as per OECD guidelines test no.420.Results: n-hexane extract of M. ferrea stamens was found most potent amongst other extracts studied for antibacterial activity; moreover it exhibited bactericidal activity against selected bacterial pathogens. The same extract exhibited good free radical scavenging activity in DPPH assay (IC50 value = 66.3 µg/ml). Phytochemical investigation of extract revealed presence of sterols, terpenoids and volatile oil components and the total terpenoid content was estimated as 102.8 mg/ml of dried extract (in terms of lupeol equivalents). The extract was found safe in mice in acute oral toxicity studies.Conclusion: M. ferrea stamens exhibited broad spectrum antibacterial activity along with good free radical scavenging potential and in-vivo safety which encourage further studies in the area.Â

Physics Potential of the ICAL detector at the India-based Neutrino Observatory (INO)

The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we present the physics potential of the detector as obtained from realistic detector simulations. We describe the simulation framework, the neutrino interactions in the detector, and the expected response of the detector to particles traversing it. The ICAL detector can determine the energy and direction of the muons to a high precision, and in addition, its sensitivity to multi-GeV hadrons increases its physics reach substantially. Its charge identification capability, and hence its ability to distinguish neutrinos from antineutrinos, makes it an efficient detector for determining the neutrino mass hierarchy. In this report, we outline the analyses carried out for the determination of neutrino mass hierarchy and precision measurements of atmospheric neutrino mixing parameters at ICAL, and give the expected physics reach of the detector with 10 years of runtime. We also explore the potential of ICAL for probing new physics scenarios like CPT violation and the presence of magnetic monopoles.Comment: 139 pages, Physics White Paper of the ICAL (INO) Collaboration, Contents identical with the version published in Pramana - J. Physic

ANTIBACTERIAL ACTIVITY, FREE RADICAL SCAVENGING POTENTIAL, PHYTOCHEMICAL INVESTIGATION AND IN-VIVO TOXICITY STUDIES OF MEDICINAL PLANT Embelia basaal (R. & S.) A. DC.

 Objective: Present extensive study on medicinal plant Embelia basaal (R. & S.) A. DC. was undertaken for evaluation and quantification of broadspectrum antibacterial activity, free radical scavenging potential, phytochemical investigation, development of high performance thin layerchromatography (HPTLC) fingerprint profile and in-vivo safety of the plant.Methods: Dried fruits of the plant were powdered and macerated in variety of solvents to obtain four extracts of different polarities. Antibacterialactivity was evaluated using agar well diffusion assay. Most potent antibacterial extract of E. basaal was selected for further extensive studies.Minimum inhibitory concentration (MIC) values of the potent antibacterial extract were determined using broth macrodilution method as per ClinicalLaboratory Standards Institute guidelines. Free radical scavenging activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl assay. Qualitativephytochemical tests, quantification of total phenolic contents and HPTLC fingerprint analysis were carried out for phytochemical investigation. Thein-vivo safety of the plant was determined by conducting acute oral toxicity studies in mice as per Organization for Economic Co-operation andDevelopment guidelines test no. 420.Results: Ethanol extract of E. basaal was found potent bactericidal against selected pathogens and chosen for further extensive studies. The extractexhibited significant free radical scavenging activity (inhibitory concentration 50 value=50 μg/mL). Phytochemical investigation revealed presenceof phenolic compounds, terpenoids, tannins and alkaloids in the test extract and it was found safe in-vivo at a dose level of 2000 mg/kg body weightof an animal.Conclusion: E. basaal was found medicinally active in the present study. Its broad spectrum antibacterial activity, significant free radical scavengingpotential and in-vivo safety will provide a platform for advance studies in the area.Keywords: Embelia basaal (R. & S.) A. DC., Bactericidal activity, Free radical scavenging activity, Phytochemical investigation, High performance thinlayer chromatography fingerprint, Acute oral toxicity

DEVELOPMENT OF ANALYTICAL METHOD FOR IDENTIFICATION OF ESSENTIAL OIL FROM BLUMEA ERIANTHA DC IN PLASMA.

Objective The present study was designed to develop a head space gas chromatography method using mass spectrometric detection for identification of essential oil constituents from Blumea eriantha DC in plasma. Methods The essential oil was extracted by hydrodistillation using Clevenger type apparatus. The rabbit plasma samples were spiked with essential oil and were further analyzed using dynamic head-space sampling with gas chromatography-mass spectrometry (GC-MS). Results The analysis of plasma samples spiked with essential oil has revealed the selective absorption of some of the essential oil components. Conclusion Analytical method has been developed for identification of essential oil constituents in plasma which will be helpful in further in vivo pharmacokinetic studies of the essential oil. KEYWORDS Blumea eriantha DC, Dynamic Headspace Sampling, GC-MS, Plasma

Attenuation of quorum sensing-regulated behaviour by Tinospora cordifolia extract & identification of its active constituents

Background & objectives: The pathogenicity of the nosocomial pathogens, Pseudomonas aeruginosa and Acinetobacter baumannii is regulated by their quorum sensing (QS) systems. The objective of the present study was to examine the effect of the cold ethyl acetate extract of Tinospora cordifolia stem on virulence and biofilm development in the wild type and clinical strains of P. aeruginosa and A. baumannii. The study was further aimed to identify the probable active constituents in the plant extract. Methods: P. aeruginosa virulence factors viz., LasA protease, LasB elastase and pyocyanin production were analyzed spectrophotometrically. Biofilm formation was studied using crystal violet staining-microtitre plate assay. The plant extract was fractionated using silica gel column chromatography and the most active fraction was derivatized using silylation and analyzed by gas chromatography-mass spectrometry (GC-MS). In silico testing of the molecules identified in GC-MS was performed, for binding to the P. aeruginosa LasI and LasR proteins, to predict the QS inhibitory molecules. Results: The plant extract inhibited three major virulence factors in P. aeruginosa; it exhibited enhanced biofilm formation in P. aeruginosa while decreased biofilm development in A. baumannii. The most active fraction obtained from column chromatography, exhibited suppression of virulence as well as biofilm in both the organisms. Docking scores were calculated for all the molecules identified in GC-MS, and high docking scores were obtained for 2,3,4-triacetyloxybutyl acetate, methyl 16-methyl heptadecanoate, 2-(5-ethenyl-5-methyloxolan-2-yl)propan-2-ol, methyl hexadecanoate and 2-methoxy-4-vinyl phenol. Interpretation & conclusions: The compounds showing high docking scores could probably be the QS inhibitors. These molecules can be screened further for the development of new anti-infective drugs