GC-MS and GC-FID analysis of volatile secondary metabolites of the root of Anaphalis contorta Hook F. from India

  ABSTRACT. The chemical composition of hydro-distilled essential oil of dried roots of Anaphalis contorta Hook F. was analyzed for the first time by using gas chromatography equipped with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The compounds of essential oil were identified according to their mass spectra and their relative retention indices determined on a capillary GC column (non-polar stationary phase). Twenty-seven compounds were identified representing 94.8% of the total oil. The major constituents were 2,2-dimethyl-2[2,4,6-trimethylphenyl] acetic acid (12.1%), labda-8,14-dien-13-ol (8.4%), δ-cadinene (8.1%), labda-7,14-dien-13-ol (6.9%), α-gurjunene (6.7%), viridiflorene (5.1%), and caryophyllene oxide (4.9%). The root essential oil of A. contorta produced different chemotypes.                 KEY WORDS: Anaphalis contorta Hook F., Essential oil composition, 2,2-Dimethyl-2[2,4,6-trimethylphenyl] acetic acid.  labda-8,14-dien-13-ol, GC/MS Bull. Chem. Soc. Ethiop. 2022, 36(1), 235-240.                                                                DOI: https://dx.doi.org/10.4314/bcse.v36i1.19                                                                                           &nbsp

Corneal Toxicity due to Datura Inoxia

Purpose: To report corneal toxicity following intentional inoculation of the juice of crushed leaves of datura (Datura Inoxia). Case Report: A 70-year-old male presented with diminished vision, redness, watering, and photophobia in his right eye one day before his presentation. The patient had instilled the juice of datura leaves in his right eye to treat his ocular problems. Slit lamp examination revealed mild conjunctival and circumcorneal congestion, corneal edema, and folds in Descemet’s membrane. The left eye was pseudophakic with an otherwise unremarkable examination. The patient was treated with dexamethasone, cycloplegics, and lubricants. The cornea did not sufficiently recover after one month of treatment leaving him with permanent corneal decompensation that required a referral for keratoplasty. The patient was followed up for six months. We hypothesize damage to the corneal endothelial Na+/K+-ATPase pump by tropane alkaloids as a cause for corneal decompensation. Conclusion: Awareness about toxicity of this commonly grown plant in the tropics and subtropics is essential in order to avoid blindness due to accidental or deliberate use

Distance Dependent Resonance Energy Transfer Between Molecular Machine and Plasmonic Nanostructure

poster abstractPhotoswitchable molecules (molecular machines) have attracted a great deal of attention over the past few years for the design of molecular sensors. Among photoswitchable molecules, azobenzene is widely studied due to its trans-cis photoisomerization, which produces a simple structure and optical and Raman spectra, and is photo and electrochemically active, and can be utilized for optical storage and other applications. Localized surface plasmon resonance (LSPR) properties of the metal nanostructures in conjunction with the photoswitching properties of the azobenzene molecules allow the nanoscale environment to be more controlled and to ultimately improve the sensing abilities of the metallic nanostructure. Herein, we develop an ultrasensitive molecular sensor by functionalizing the gold nanoprism with a selfassembled monolayer of alkanethiols containing azobenzenes. This is the first study where light-induced reversible switching of azobenzenes to cis and trans conformations was detected by monitoring the LSPR of gold nanoprisms-based sensing platforms. It was found that the LSPR red shift was observed as the light exposure was switched from UV to blue light due to the cis to trans isomerization of the azobenzene. This shift is consistent with the increase in thickness of the local dielectric environment (0.6 nm) surrounding the nanoprisms with perhaps a contribution from electronic interaction between the nanoprisms and azobenzene. We hypothesize that this electronic interaction is the nearfield resonance energy transfer (NF-RET). Changing the alkanethiol chain length altered the distance between the nanoprisms’ surface to the azobenzene. The LSPR red shift decreases as the distance between azobenzenes and nanoprisms increases due to the decrease in NF-RET. The LSPR shift was found to be reversible as the light source was switched back and forth several times from UV to blue light. The effects of the azobenzene conformational change and its photoreversibility were also probed through surface enhanced Raman spectroscopy (SERS) demonstrating that the NF-RET between the nanoprisms and bound azobenzenes in their cis conformation significantly enhances the intensity of the Raman bands of the azobenzenes and is highly dependent on the distance of azobenzene from the surface of the nanoprisms. The SERS data suggested that the isomerization was controlled by first-order kinetics with a rate constant of 1.0 x 10−4 s−1. Our demonstration of light-induced photoreversibility of this type of molecular machine is the first step toward eliminating current limitations on detection of molecular motion in solid-state devices using LSPR spectroscopy with nanoprisms. Modulating the LSPR position and controlling energy transfer across the nanostructure organic molecule interface are very important for the fabrication of plasmonic-based nanoscale devices

Investigating the Effects of Size and Shape of Anisotropic Nanostructures on the Molecular Sensor Response

The photoreversiblity of molecular machine-attached onto anisotropic nanostructures have been studied using optical spectroscopy. For the first time, we have observed an unprecedented 21-nm shift of localized surface plasmon resonance (LSPR) peak of gold nanoprism upon cis to trans isomerization of azobenzenes. The observed shift was a combined effect of energy transfer across the nanostructure and azobenzene molecule and increase in the dielectric environment of the nanostructure. Furthermore, we also investigated the geometrical effects of plasmonic nanostructures by fine-tuning their size and shape on sensitivity of molecular sensors and determined the mechanism underlying LSPR peak shifts. Understanding such mechanism will aid in designing highly efficient sensing platforms for future optoelectronic device fabrication

Nanoplasmonic sensor for the detection of cardiac Troponin

poster abstractThe Isoform of troponin I is uniquely produce in the adult human myocardium and it overexpress at myocardial injury. Accordingly, Iso troponin 1 level in plasma and other biological fluids can serve as diagnostic and prognostic disease biomarkers. Our study focus on the design of a label free ultrasensitive nanoplasmonic sensor by utilizing unique localized surface Plasmon resonance (LSPR) property of highly sensitive gold nanoprisms. Herein our study reveals that chemically synthesized nanoprisms with 42 nm average edge lengths can be used in nanoplasmonic sensor fabrication for the troponin detection. The limit of detection has been found to be sub-picomolar concentrations in PBS buffer and we will explore this sensing mechanism to detect Troponin I of myocardial infarction patient’s samples

Post Liberalization Growth in TFP of Selected Indian Manufacturing Industries: A Stochastic Frontier Decomposition Analysis

This dissertation establishes a stochastic frontier for six Indian manufacturing industries. Three models are established and decomposed: the cross-section model, the time invariant model and the time varying decaying model. All three models have been used to check the robustness of the results. The analysis uses CMIE data which is in panel data frame work. The major finding is that most industries have declined in their technical efficiency and Total factor productivity. The implementation has been done using STATA11

Annealing-Induced Modifications in Physicochemical and Optoelectronic Properties of Ag-Doped Nanostructured CdS Thin Films

The Ag-doped nanostructured CdS thin films are grown by simple, cost effective chemical ion exchange technique at room temperature on ITO-coated glass substrate. These as grown thin films are annealed at 100, 200, 300, and 400°C in air atmosphere for 1 hour. To study the effect of annealing on physicochemical and optoelectronic properties, these as grown and annealed thin films are characterized for structural, compositional, morphological, optical, and electrical properties. X-ray diffraction (XRD) pattern reveals polycrystalline nature of these thin films with increase in crystallite size from 6.4 to 11.2 nm, from XRD the direct identification of Ag doping in CdS thin films cannot be judged, while shift in characteristics peak position of CdS is observed. The Raman spectrum represents increase in full width at half maxima and intensity of characteristic peak, confirming the material modification upon annealing treatment. Presence of Cd, Ag, and S in energy dispersive X-ray analysis spectra (EDAX) confirms expected elemental composition in thin films. Scanning electron microscopy (SEM) images represent grain growth and agglomeration upon annealing. Red shift in optical absorbance strength and energy band gap values from 2.28 to 2.14 eV is obtained. I-V response obtained from as grown and annealed thin films shows an enhancement in photosensitivity from 72% to 96% upon illumination to 100 mW/cm2 light source

Prescription pattern of drugs in ENT outpatient department of tertiary care teaching hospital

Background: Diseases of the ear, nose and throat (ENT) are common among general population affecting all age groups and accounts for most of the drugs prescribed and used. The aim of the study is to assess the prescription pattern of drugs in ENT outpatient department in a tertiary care teaching hospital.Methods: A prospective observational study was conducted from December 2017 to May 2018 in the ENT OPD (Outpatient department) at Pt. J.N.M. Medical College and associated Dr. B.R. Ambedkar Memorial Hospital, Raipur. Data were collected in a proforma and evaluated.Results: A total of 313 prescriptions were analysed. Most of the patients (40.89%) belonged to 13 - 35 years age group.185 patients (59.10%) were male and 128 patients were females (40.90%). A total of 1003 drugs were prescribed. The average number of drugs per prescription was 3.2. Most common class of drugs prescribed was antimicrobials (24.42%), followed by H1 antihistaminics (18.84%), antiulcer drugs (15.55%) and nonsteroidal anti-inflammatory (NSAIDs) drugs (14.35%). The average number of antimicrobials per prescription was 0.78. One or two antimicrobials were prescribed in 202 prescriptions (64.53%). The most common prescribed antimicrobial was of Penicillin group (64.89%) followed by Fluoroquinolone (25.71%). The most common prescribed route of drug administration was oral route (81.35%). The most common prescribed dosage form was tablets (74.87%). FDC constituted 24.62% of prescribed drugs.Conclusions: The study revealed that the most common class of drug prescribed was antimicrobials followed by H1 antihistaminics, antiulcer drugs and NSAIDS