Ravi Kant Khajuria

THE GASTRIC ULCER PROTECTIVE EFFECT OF BOSWELLIC ACIDS, A LEUKOTRIENE INHIBITOR FROM BOSWELLIA SERRATA, IN RATS

Aim of the study is to evaluate the anti-ulcer efficacy of the boswellic acids (BA), a triterpenoid known as anti-inflammatory/anti-arthritic agent, which is in clinical use. The reason for the study is that, the known non-steroidal anti-inflammatory drugs (NSAIDs) are full of side effects especially ulceration which is at the top. BA, although, used as an anti-arthritic agent yet it is not only devoid of ulcer production but protective also. The activity evaluation was done by the following universally accepted animal models viz., pyloric ligation, ethanol-HCl, acetylsalicylic acid, indomethacin and cold restrained stress-induced ulceration in rats. Results of the present study revealed that BA possess a dose dependent antiulcer effect against different experimental models. It showed different degree of inhibition of the ulcer score towards different ulcerogenic agents. The ulcer score against various ulcer inducing agents viz., pyloric ligation, ethanol/HCl, (acute and chronic) acetylsalicylic acid, indomethacin and cold restraint stress, was inhibited by 39%, 38%, 51%, 31%, 37% and 42% respectively at 250mg/kg. From the data it is concluded that BA inhibited ulcer production non-specifically in all the experimental models, whereby, it is not possible to propose a single specific mechanism. Nevertheless it is possible that BA might be acting by increasing the gastric mucosal resistance and local synthesis of cytoprotective prostaglandins and inhibiting the leukotriene synthesis.

Withanolide production by in vitro cultures of Withania somnifera and its association with differentiation

Withanolides-steroidal lactones, isolated from various Solanaceous plants have received considerable attention due to their potential biological activities. Five selected withanolides (withanone, withaferin A, withanolide A, withanolide B, withanolide E) were identified by HPLC-UV (DAD) — positive ion electrospray ionization mass spectroscopy in Withania somnifera (L.) Dunal cv. WSR plants and tissues cultured in vitro at different developmental phases. Cultures were established from five explants on Murashige and Skoog’s medium supplemented with different plant growth regulators. Results suggest that production of withanolides is closely associated with morphological differentiation.

Characterization of a new rat urinary metabolite of piperine by LC/NMR/MS studies.

Potential of piperine, an active alkaloid of black and long peppers, to increase the bioavailability of drugs in humans is of great clinical significance owing to its omnipresence in food. In an attempt to further study the reported differences in its metabolism in rats and humans, a new major urinary metabolite was detected in rat urine and plasma using HPLC. The metabolite was partially purified using reverse phase column chromatography on Sephadex((R))-LH 20 and characterized as 5-(3, 4-methylenedioxy phenyl)-2E,4E-pentadienoic acid-N-(3-yl propionic acid)-amide with the help of LC/NMR/positive ESI-MS studies. Complete mass fragmentation pattern could be assigned with MS/MS studies. The metabolite has a unique structure compared to the previously reported metabolites in that it retains methylenedioxy ring and conjugated double bonds while the piperidine ring is modified to form propionic acid group. Mechanism of formation of the metabolite by oxidation and cleavage of piperidine ring is proposed. Kidney appears to be the major excretion route for piperine metabolites in rats as no metabolite could be detected in feces.

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.

Comparative studies and identification of camptothecin produced by an endophyte at shake flask and bioreactor

The fungus showing homology with Nodulisporium by 28S ribosomal gene sequencing, which has been discovered as an endophyte on medicinal plant Nothapodytes foetida, was found to produce 45 and 5.5 µg of camptothecin (CPT) per gram of mycelia at bioreactor and at shake flask, respectively, which was further quantified and characterised by various spectroscopic analyses.

In vitro and in vivo aphrodisiac properties of Corchorus depressus Linn. on rabbit corpus cavernosum smooth muscle relaxation and sexual behavior of normal male rats

ETHNOPHARMACOLOGICAL RELEVANCE Corchorus depressus Linn. has been used as an aphrodisiac in traditional Indian medicine to treat male sexual dysfunction and impotency. AIM OF THE STUDY The petroleum ether, chloroform, ethyl acetate, n-butanol and aqueous fractions of 95% methanol extract of Corchorus depressus were screened initially for their in vitro aphrodisiac activity on rabbit corpus cavernosum smooth muscle. The chloroform fraction (CDC) was found to be the most active and therefore investigated further on general mating behavior, libido and potency of normal male Wistar albino rats in comparison with the standard drug, Sildenafil citrate. MATERIALS AND METHODS Animals were divided into the following groups: Control, SC CDC 100, CDC 200, and CDC 400, who received saline, Sildenafil citrate or the chloroform fraction of Corchorus depressus at doses of 100, 200 or 400mg/kg b.wt., respectively. The route of administration for all the groups was oral dosing, which was once in a day for 45 days. To analyze the mating behavior, female rats with estrus phase were used. RESULTS The chloroform fraction of methanolic extract of Corchorus depressus significantly reduced ML, IL, PEI and III. There was a significant increase in the MF, IF and EL and serum testosterone levels throughout the study period. The potency test significantly increased erections, quick flips, long flips and total reflex. In vitro aphrodisiac activity was significantly higher in chloroform fraction at a concentration of 25.0mg/ml, which induced 71.4% relaxation. The combined results of the above mentioned models indicate that the chloroform fraction of Corchorus depressus produces a significant increase in sexual activity as exhibited by 25mg/ml in vitro and 400mg/kg in vivo. In comparison with the control, all the drug-treated groups have shown drug-induced effects for a few parameters. CONCLUSIONS In vitro and in vivo studies provide valuable experimental evidence that the chloroform fraction of methanolic extract of Corchorus depressus possesses aphrodisiac property. This study further substantiates the ethnopharmacological claims of Corchorus depressus as a sexual stimulating agent and offers a significant potential for studying the effect on male sexual response and its dysfunctions.

Synthesis and Structure-Activity Relationships of Vasicine Analogues as Bronchodilatory Agents

The series of vasicine (1) analogues, an alkaloid from Adhatoda vasica Nees., were synthesized with changes in A, B or C rings. Compounds 13-19 were evaluated for in vitro bronchodilatory activity using isolated guinea pig tracheal chain. Compounds 3-8 were also synthesized in good yields using microwave-mediated synthesis under solvent free conditions. Compounds 5 and 8 with seven-member C ring were more active than etofylline and caused 100% relaxation of both the histamine and acetycholine pre-contracted guinea pig tracheal chain. The structure-activity relationship studies showed that the quinazoline and oxo functionalities were essential for activity. The compounds without C ring and instead having aliphatic and phenyl substitutions in B ring showed relaxation against histamine pre-contracted tracheal chain only, 2-methyl substituted analogues, 12 and 13, being most active with 100% relaxation effect.

Production of rohitukine in leaves and seeds of Dysoxylum binectariferum: An alternate renewable resource

Abstract Context: Rohitukine is an important precursor for the synthesis of potential anticancer drugs flavopiridol (Sanofi-Aventis) and P-276-00 (Piramal Healthcare Limited, Mumbai, India). Trunk bark of Dysoxylum binectariferum (Roxb.) Hook. f. ex Bedd. (Meliaceae) is the widely used source for isolation of rohitukine. However, removal of trunk bark threatens the survival of the tree. Objective: To investigate the amount of rohitukine accumulated in other tissues of D. binectariferum. Materials and methods: Rohitukine standard was isolated from leaves of D. binectariferum. Its purity was ascertained using HR-MS and NMR. Crude extracts were prepared from different tissues of D. binectariferum. Rohitukine content in all the tissues was quantified by HPLC. Results: Rohitukine accumulates in a significant amount in seeds, trunk bark, leaves, twigs, and fruits of D. binectariferum. Seeds have the highest rohitukine content (2.42%, dry weight) followed by trunk bark (1.34%, dry weight), leaves (1.064%, dry weight), twigs (0.844% dry weight), and fruits (0.4559% dry weight). Discussion and conclusion: Seeds and leaves of D. binectariferum could be used as alternate renewable sources for isolation of rohitukine.

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.

Variability and selection on different Argyrolobium roseum accessions for morphological traits and yield

Variability studies were carried out among different accessions of Argyrolobium roseum for 12 metric traits under natural and cultivated conditions. Almost all characters showed higher values in cultivated than natural population. Leaf breadth recorded highest CV (30.59%). Highest percentage of vitexin and D-pinitol (0.208 and 0.773% dwb) was observed in RAR-7 and RAR-6, respectively, under cultivated conditions. Phenotypic coefficient was higher than genotypic coefficient of variation. The association analysis revealed that root yield had positive significant correlation with 100 seed weight (r=0.839) biomass yield (r=0.601), where biomass yield had a positive significant correlation with leaf length, single pod weight. High heritability (97.4–99.8%) coupled with moderate genetic advance ranged between (49–67%) as a percent of mean was observed for leaf breadth, pod length, total foliage biomass yield and total root yield/plant. This suggests that direct selection for these traits is suitable for the improvement of this crop.