Rajneesh Anand

Chemical composition, antioxidant and antibacterial activities of the leaf essential oil of Juglans regia L. and its constituents

The essential oil from the leaves of Juglans regia L. (Juglandaceae) growing wild in Kashmir (India) was obtained by hydrodistillation and analysed by a combination of capillary GC-FID and GC-MS. A total of 38 compounds, representing 92.7% of the oil, were identified and the major components were found to be α-pinene (15.1%), β-pinene (30.5%), β-caryophyllene (15.5%) germacrene D (14.4%) and limonene (3.6%). The essential oil and the main individual constituents were screened for antibacterial activity and the essential oil evaluated for antioxidant activity. Antibacterial activity was evaluated using the disc diffusion and microdilution methods against a group of clinically significant Gram-positive (Staphylococcus epidermidis MTCC-435, Bacillus subtilis MTCC-441, Staphylococcus aureus) and Gram-negative bacteria (Proteus vulgaris MTCC-321, Pseudomonas aeruginosa MTCC-1688, Salmonella typhi, Shigella dyssenteriae, Klebsiella pneumonia and Escherichia coli). The essential oil and its major components exhibited broad spectrum inhibition against all the bacterial strains with Gram-positive being more susceptible to the oil than Gram-negative bacteria. Antioxidant activity of the oil was evaluated by the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl radicals. In general, the essential oil exhibited high antioxidant activity which was comparable to the reference standards at the same dose (ascorbic acid and butylated hydroxyl toluene, BHT) with IC(50) values of 34.5 and 56.4μg/ml calculated by DPPH and hydroxyl radical scavenging assays respectively.

Simultaneous determination of etoposide and a piperine analogue (PA-1) by UPLC–qTOF-MS: Evidence that PA-1 enhances the oral bioavailability of etoposide in mice

In the present investigation, a UPLC-qTOF-MS/MS method has been developed for the simultaneous determination of etoposide and a piperine analogue, namely, 4-ethyl 5-(3,4-methylenedioxyphenyl)-2E,4E-pentadienoic acid piperidide (PA-1). The analytes were separated on a reverse phase C18 column using methanol-water (72:28, v/v) mobile phase with a flow rate of 250 microL/min. The qTOF-MS was operated under multiple reaction monitoring mode using electro-spray ionization (ESI) technique with positive ion polarity. The major product ions for etoposide and PA-1 were at m/z 185.1350 and 164.1581, respectively. The recovery of the analytes from mouse plasma was optimized using solid phase extraction technique. The total run time was 6 min and the elution of etoposide and PA-1 occurred at 1.24 and 2.84 min, respectively. The calibration curves of etoposide as well as PA-1 were linear over the concentration range of 2-1000 ng/mL (r(2), 0.9829), and 1-1000 ng/mL (r(2), 0.9989), respectively. For etoposide intra-assay and inter-assay accuracy in terms of % bias was in between -7.65 to +6.26, and -7.83 to +5.99, respectively. For PA-1 intra-assay and inter-assay accuracy in terms of % bias was in between -7.01 to +9.10, and -7.36 to +6.71, respectively. The lower limit of quantitation for etoposide and PA-1 were 2.0 and 1.0 ng/mL, respectively. Analytes were stable under various conditions (in autosampler, during freeze-thaw, at room temperature, and under deep-freeze conditions). The method was used for a pharmacokinetic study which showed that PA-1 enhanced the oral bioavailability of etoposide in mice by 2.32-fold.

Essential oil composition of Senecio graciliflorus DC: comparative analysis of different parts and evaluation of antioxidant and cytotoxic activities.

The essential oil of different parts of Senecio graciliflorus DC was obtained by hydrodistillation and analysed by GC-FID and GC-MS for the first time. A total of 17, 20, 19 and 17 constituents were identified comprising 99.90, 95.50, 98.93 and 95.96% of the essential oil of flower, leaf, stem and root parts of Senecio graciliflorus respectively. Monoterpene hydrocarbons predominated in the essential oil with 85.28% in flower, 57.53% in leaf, 67.74% in stem and 64.98% in root oil. α-pinene, cis-ocimene, 1,2,3-trimethylcyclohexane and β-pinene were the major constituents of the essential oil. The flower essential oil exhibited a strong antioxidant potential displaying IC50 values of 21.6±0.6 and 26.0±1.0μg/ml in DPPH and hydroxyl radical assays respectively. On the other hand the essential oil of flower and root displayed highest cytotoxicity against lung (A-549) cancer cell lines (IC50=19.1±0.9 and 21.3±1.1μg/ml respectively. This study which represents the first report of the essential oil composition and bioevaluation of Senecio graciliflorus, can serve as a new source of cytotoxic and antioxidant activity.

Essential oil composition of Artemisia dracunculus L. (Tarragon) growing in Kashmir - India.

Abstract Two distinct chemotypes of Artemisia dracunculus were found in Kashmir. The oils from these two distinct chemotypes were analysed by GC and GC-MS. The chemical constituents of local variety were α-pinene (0.7%), myrecene (1.2 %), limonene (3.5 %), Z-(β)-ocimene (12.7 %), E-(β)-ocimene (4.6 %), α-terpinolene (2.7 %), 5-phenyl-l,3-Pentadiyne (5.1 %), methyl eugenol (0.7 %), capillene (60.2 %), elemicin (2.3 %), bicyclogermacrene (0.5 %), iso-elemicin (2.1 %) and germacrene-B (0.6 %). The major chemical constituents found in exotic variety are α-pinene (1.4 %), β-pinene (0.3 %), myrecene (0.1 %), p-cymene (0.2 %), limonene (2.8 %), Z-(β)-ocimene (1.6 %), E-(β)-ocimene (1.0 %), γ-terpinene (0.3 %) linalool (1.2 %), β-thujone (0.4 %),camphor (0.4 %), methyl chavicol (71.3 %), iso-menthol (0.1 %), bornyl acetate (0.7 %), carvacraol (7.7 %), α-terpinyl acetate (0.2 %), hexyl hexanoate (0.5 %), α-copaene (2.2 %), β-caryophyllene (0.2 %). The chemical constituents of the volatile oil are similar to French Tarragon.

EXTRACTION STUDIES OF PODOPHYLLUM HEXANDRUM USING CONVENTIONAL AND NONCONVENTIONAL METHODS BY HPLC–UV–DAD

The composition of lignans extracted from Podophyllum hexandrum rhizomes was studied by sequential extraction with supercritical CO2, ethyl acetate modified CO2 and methanol modified CO2. The results were compared with the extracts obtained by Accelerated Solvent Extraction (ASE) and soxhlets methods. The lignan contents comprised of Podophyllotoxin, deoxypodophyllotoxin, 4′-demethylpodophyllotoxin, Picropodophyllotoxin, Isopicropodophyllotoxin, Podophllotoxin-β-D-glucopyranoside, and 4′-demethylpodophyllotoxin β-D-glucopyranoside in the extracts of Podophyllum hexandrum rhizomes obtained by different methods was studied. There was a variation in the concentration of lignan in the extracts obtained by different methods of extraction. Podophyllotoxin formed the major component (36.55%) of the extract obtained by SFE and picropodophyllotoxin, isopicropodophyllotoxin, deoxypodophyllotoxin, and 4′-demethylpodophyllotoxin were present in 6.82, 1.51, 1.46, and 0.85%, respectively, whereas 4′-demethylpodophyllotoxin β-D-glucopyranoside was 1.89% in the extract obtained by ASE, which is higher than SFE extracts. Soxhlets derived extract contains better concentration of isopicropodophyllotoxin (24.49%) than SFE. A simple, isocratic, and reliable analytical HPLC-UV (DAD) method was developed for simultaneous identification and quantification of different seven lignans in the extracts of different extraction techniques.

Development of a validated UPLC–qTOF-MS/MS method for determination of bioactive constituent from Glycyrrhiza glabra

Abstract An ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC–qTOF-MS/MS) method was developed and validated for the simultaneous determination of glycyrrhizin and glycyrrhetic acid. These analytes were separated on a reverse phase C18 column using a mobile phase of acetonitrile:2% acetic acid in water (75:25, v/v) with a flow rate of 200μL/min. The qTOF-MS was operated under multiple reaction monitoring (MRM) mode using the electrospray ionization (ESI) technique with positive ion polarity. A comparison of three different extraction techniques i.e. accelerated solvent extraction (ASE), extraction under ultrasonic waves (USW) and the classical extraction by percolation (CE) method was done and quantification of these extracts was also carried out by the proposed method.