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Rakesh Maurya

Publications and source records attributed to Rakesh Maurya.

18 recordsLinked to original sources
PubMed2006

New antifungal flavonoid glycoside from Vitex negundo.

Flavonoids are ubiquitous in photosynthesizing cells and are common part of human diet. For centuries, preparations containing these compounds as the principal physiologically active constituents have been used to treat human diseases. Increasingly, this class of natural products is becoming the subject of anti-infective research. Our bioactivity guided fractionation of ethanolic extract of leaves of Vitex negundo resulted in the isolation of new flavone glycoside (4) along with five known compounds 1-3, 5 and 6. All the isolated compounds were evaluated for their antimicrobial activities. The new flavone glycoside 4 and compound 5 were found to have significant antifungal activity against Trichophyton mentagrophytes and Cryptococcus neoformans at MIC 6.25 microg/ml.

Antifungal Agents↗
PubMed2006

Synthesis of novel benzofuran isoxazolines as protein tyrosine phosphatase 1B inhibitors.

PTPases are considered to be involved in the etiology of diabetes mellitus and neural diseases, such as Alzheimer's disease and Parkinson's disease. Therefore, PTPase inhibitors should be useful tools to study the role of PTPases in these diseases and other biological phenomena, and which can be developed into chemotherapeutic agents. In the present study, we have synthesized novel benzofuran isoxazolines 13-21 via 1,3-dipolar cycloaddition reaction using karanjin (1) and kanjone (2), isolated from Pongamia pinnata fruits. All the synthesized compounds were evaluated against PTPase enzyme. Compounds 19 and 20 displayed significant inhibitory activity with IC50 values 76 and 81 microM, respectively.

Benzofurans↗
PubMed2006

Neuroprotective effect of Acorus calamus against middle cerebral artery occlusion-induced ischaemia in rat.

The neuroprotective potential of ethanol:water (1:1) extract of rhizomes of Acorus calamus (AC-002) has been investigated in middle cerebral artery occlusion (MCAO)-induced ischaemia in rats. A significant behavioural impairment in Rota-Rod performance and grid walking was observed in rats, 72 hours after MCAO as compared to sham-operated animals. These rats also exhibited an increase in lipid peroxidation (cortex -157%, corpus striatum - 58%) and a decrease in glutathione levels (cortex - 59%, corpus striatum - 34%) and superoxide dismutase (SOD) activity (cortex - 64%, corpus striatum - 32%) as compared to sham-operated animals. Ischaemic rats treated with AC-002 (25 mg/kg, p.o.) exhibited a significant improvement in neurobehavioural performance viz. Rota-Rod performance and grid walking as compared to the MCAO group. Interestingly, treatment with AC-002 in MCAO rats significantly decreased malonaldialdehyde levels in cortex as compared to ischaemic rats. A significant increase in reduced glutathione levels and SOD activity was also observed both in cortex and corpus striatum in MCAO rats treated with AC-002 in comparison to MCAO rats. Treatment with AC-002 in MCAO rats also reduced the contralateral cortical infarct area (19%) as compared to MCAO rats (33%). Neurological function score was improved in the AC-002-treated rats as compared to the MCAO group. The results of the present study indicate the neuroprotective efficacy of A. calamus in the rat model of ischaemia.

Acorus↗
PubMed2005

Glycolipids and other constituents from Desmodium gangeticum with antileishmanial and immunomodulatory activities.

Nineteen compounds of various classes, such as flavonoid glycosides, pterocarpanoids, lipids, glycolipids, and alkaloids, were isolated and identified from the Desmodium gangeticum whole plant. Aminoglucosyl glycerolipid (8) is reported here for the first time. Its structure has been elucidated by spectroscopic and degradation studies. This novel compound exhibited in vitro antileishmanial and immunomodulatory activities, as it enhanced nitric oxide (NO) production and provided resistance against infection established in peritoneal macrophages by the protozoan parasite Leishmania donovani. Another known compound, glycosphingolipid (cerebroside) (7) was found to possess significant in vitro antileishmanial and immunomodulatory activities against the same parasite. Other compounds were found to be inactive.

Animals↗
PubMed2005

Allophylus serratus: a plant with potential anti-ulcerogenic activity.

Allophylus serratus is known to possess various therapeutic properties. We evaluated the anti-ulcerogenic property of crude ethanolic extract of Allophylus serratus (AS) in different ulcer models in Sprague-Dawley rats. The extract at 400 mg/kg body weight, once daily, orally has a significant effect in cold restraint (CRU, 2 h cold restraint stress), aspirin (ASA, 150 mg/kg body weight, orally), alcohol (AL, 1 ml/200 gm of absolute alcohol) and pyloric ligation (PL, 4h ligation) induced gastric ulcer models as it showed protection index of 71.28, 62.50, 90.84 and 64.29% protection, respectively whereas, standard drug omeprazole (OMZ, 10mg/kg body weight) has shown protection index of 85.70, 74.99 and 74.99 in CRU, ASA and PL model respectively. Sucralfate (SUC, 500 mg/kg body weight) as a standard drug in AL model has 93.20% protection. Furthermore, AS has significantly decreased the free acidity (72.41%), total acidity (47.97%) and peptic activity (24.59%), respectively as well as has significantly increased the mucus secretion (29.41%). Conclusively the ulcer protective effect of AS may be due to its anti-secretory along with cytoprotective mechanism.

Administration, Oral↗
PubMed2005

Furanoflavonoids: an overview.

The review covers the phytochemistry and pharmacology of furanoflavonoids describing 291 compounds and containing 228 references.

Flavonoids↗
PubMed2005

Efficacy of Desmodium gangeticum extract and its fractions against experimental visceral leishmaniasis.

Crude ethanolic extract of Indian medicinal plant, Desmodium gangeticum (A001) and its three fractions-hexane (F002), n-butanol (F003) and aqueous (F004) were evaluated chemoprophylactically and chemotherapeutically against experimental visceral leishmaniasis in hamsters. Ethanolic extract showed 41.2+/-5.3% inhibition of parasite multiplication when administered at a dose of 250 mg/kgx2 on day -7 and +7 of Leishmania donovani challenge. Its n-butanol fraction exhibited better efficacy than the ethanolic extract to the tune of 66.7+/-6.1% inhibition when administered at similar dose schedule. But the other two fractions failed to exert any action prophylactically. F003 also imparted significant (P<0.001) non-specific resistance to peritoneal macrophages against Leishmania infection. F003 also showed moderate antileishmanial activity when tested against established infection of Leishmania donovani in hamsters but the rest three fractions failed to show any significant inhibition of parasite multiplication. These findings revealed that this plant has potential prophylactic and therapeutic efficacy against Leishmania infection and warrants detailed investigations on its possible immunopotentiatory actions.

1-Butanol↗
PubMed2005

Synthesis of 4-hydroxy-1-methylindole and benzo[b]thiophen-4-ol based unnatural flavonoids as new class of antimicrobial agents.

Synthesis of nitrogen and sulfur heterocyclic mimics of furanoflavonoids have been achieved for the first time. Synthesized flavonoid alkaloids and thiophenyl flavonoids have been screened for antifungal and antibacterial activities. All the test compounds barring 25 exhibited antifungal activity. The compound 19 was the best and showed comparable MICs to the known compound karanjin. Compounds 5, 12, 14 and 22 also showed comparable MIC to karanjin.

Flavonoids↗
PubMed2005

Immunosuppressive properties of flavonoids isolated from Boerhaavia diffusa Linn.

Plant extracts have been widely evaluated for possible immunomodulatory properties. We have earlier reported that ethanolic extract of Boerhaavia diffusa root, a plant used in Indian traditional medicine, has significant immunomodulatory potential. B. diffusa hexane, chloroform and ethanol extracts, and two pure compounds Bd-I (eupalitin-3-O-beta-D-galactopyranoside) and Bd-II (eupalitin) were evaluated in vitro for their effect on T cell mitogen (phytohemagglutinin; PHA) stimulated proliferation of human peripheral blood mononuclear cell (PBMC), mixed lymphocyte culture, lipopolysaccharide (LPS) stimulated nitric oxide production by RAW 264.7, PHA and LPS induced IL-2 and TNF-alpha production, in human PBMCs, superoxide production in neutrophils, human natural killer (NK) cell cytotoxicity and nuclear translocation of nuclear factor-(kappa)B and AP-1 in PHA stimulated PBMCs. The chloroform and ethanol extracts inhibited PHA stimulated proliferation of peripheral blood mononuclear cells, two-way MLR, NK cell cytotoxicity as well as LPS induced NO production by RAW 264.7; the hexane extract showed no activity. Bd-I purified from the ethanolic extract at equivalent dose, inhibited PHA-stimulated proliferation of peripheral blood mononuclear cells, two-way MLR and NK cell cytotoxicity as well as LPS induced NO production by RAW 264.7 equally or more effectively than the parent ethanolic extract. Bd-I inhibited production of PHA stimulated IL-2 at the protein and mRNA transcript levels and LPS stimulated TNF-alpha production in human PBMCs; it also blocked the activation of DNA binding of nuclear factor-(kappa)B and AP-1, two major transcription factors centrally involved in expression of the IL-2 and IL-2R gene, which are necessary for T cell activation and proliferation. Our results report selective immunosuppressive activity of B. diffusa leaf extracts and that this activity lies in eupalitin-3-O-beta-D-galactopyranoside (Bd-I) isolated and purified from the ethnaolic extract. Thus, Bd-I could be a candidate for development as an immunosuppressive agent.

Animals↗
PubMed2005

Adaptogenic and anti-amnesic properties of Evolvulus alsinoides in rodents.

Evolvulus alsinoides (EA) is well known for its memory enhancement, antiepileptic and immunomodulatory properties in the traditional Indian system of medicine, Ayurveda. In view of the increasing attention towards plants offering non-specific resistance (adaptogens) towards stress, we have evaluated crude ethanolic extract of EA for its adaptogenic and memory enhancing properties in rodents. Adaptogenic activity was assessed in rats subjected to acute and chronic unpredictable stress. Male Sprague-Dawley rats, weighing 180-200 g were immobilized for 150 min once only in acute stress (AS) model, whereas in chronic unpredictable stress (CUS) model rats were subjected to different types of stressors daily for 7 days. Stress exposure has induced gastric ulceration with increase in adrenal gland weight, plasma creatine kinase (CK), and corticosterone level in AS and CUS. However plasma glucose was increased only in AS. Rats were treated with graded doses of crude ethanolic extract of EA (100, 200 and 400 mg/kg p.o.) for 3 days and subjected to AS on 3 day after 45 min of last dose. In CUS, EA at a dose of 200 mg/kg p.o. found effective in acute studies was administered 45 min prior to stress regimen for 7 days. EA reduced the stress induced perturbations similar to Panax quinquefolium (PQ) (100 mg/kg p.o.), a well known adaptogen. EA (100 mg/kg) administered orally for 3 days in adult male Swiss mice, was effective in decreasing scopolamine induced deficit in passive avoidance test. The improvement in the peripheral stress markers and scopolamine induced dementia by EA in the present study indicates the adaptogenic and anti-amnesic properties of EA.

Adaptation, Psychological↗
PubMed2005

Chemical constituents of Bacopa procumbens.

Phytochemical investigation of Bacopa procumbens afforded two new phenolic glycosides 1 and 2, for the first time, along with 12 known compounds 3-14. Structures of these compounds were established based on spectral and chemical evidences.

Bacopa↗
PubMed2005

Desmodium gangeticum: a potent anti-ulcer agent.

The present study was designed to investigate anti-ulcerogenic property of ethanolic extract of Desmodium gangeticum (DG) against cold restraint (CRU, 2 hr cold restraint stress), aspirin (ASP, 150 mg/kg orally), alcohol (AL, absolute alcohol 1 ml/200gm) and pyloric ligation (PL, 4 hr pylorus ligation) induced gastric ulcer models in Sprague Dawley rats, and histamine (HST, 0.25 mg/kg) induced duodenal ulcer in guinea pigs. We found that DG at a dose of 200mg/kg, (orally), markedly decreased the incidence of ulcers in all the above models. DG showed significant protection against CRU (68.37%), AL (88.87%), ASP (38.2%), PL (40.63%) and HST (63.15%) induced ulcer models, whereas standard drug omeprazole (OMZ) showed protection index of 83.86, 56.35, 70.31 and 84.21%, respectively in CRU, ASP, PL and HST models. Sucralfate as standard drug showed 92.64% protection in AL model. DG significantly reduced acid secretion 41.61%, whereas OMZ produced 43.13% reduction. Treatment with DG showed increase in mucin secretion by 56.17%, whereas OMZ showed 12.45% increase. Anti-ulcer effect of DG may be due to its cytoprotective effect along with antisecretory activity and could act as a potent therapeutic agent against peptic ulcer disease.

Alcohols↗
PubMed2004

Evaluation of anti-ulcerogenic and ulcer-healing properties of Ocimum sanctum Linn.

Ocimum sanctum (OS) is known to possess various therapeutic properties. We evaluated its anti-ulcerogenic activity in cold restraint (CRU), aspirin (ASP), alcohol (AL), pyloric ligation (PL) induced gastric ulcer models in Sprague-Dawley rats, histamine-induced duodenal (HST) ulcer in guinea pigs, and ulcer-healing activity, in acetic acid-induced (AC) chronic ulcer model. We found that OS, decreased the incidence of ulcers and also enhanced the healing of ulcers. OS at a dose of 100 mg/kg was found to be effective in CRU (65.07%), ASP (63.49%), AL (53.87%), PL (62.06%), and HST (61.76%) induced ulcer models and significantly reduced free, total acidity and peptic activity by 72.58, 58.63, 57.6%, respectively, and increased mucin secretion by 34.61%. Additionally, OS completely healed the ulcers within 20 days of treatment in AC. We observed that anti-ulcer effect of OS may be due to its cytoprotective effect rather than antisecretory activity. Conclusively, OS was found to possess potent anti-ulcerogenic as well as ulcer-healing properties and could act as a potent therapeutic agent against peptic ulcer disease.

Animals↗
PubMed2004

Furanoflavonoids from Pongamia pinnata fruits.

Fruits of Pongamia pinnata afforded four new furanoflavonoids, pongapinnol A-D (1-4), and a new coumestan, pongacoumestan (5) along with thirteen known compounds 6-18. Compounds 16 and 17 are isolated for the first time from this plant. The structures of isolated compounds were elucidated on the basis of spectroscopic data interpretation.

Flavonoids↗
PubMed2004

Furanoflavonoid glycosides from Pongamia pinnata fruits.

Pongamia pinnata fruits afforded three new furanoflavonoid glucosides, pongamosides A-C (1-3), and a new flavonol glucoside, pongamoside D (4). The structures of these compounds were established on the basis of spectroscopic studies. This is the first time that furanoflavone glucosides have been found as naturally occurring compounds.

Flavonoids↗
PubMed2004

Constituents of Pterocarpus marsupium: an ayurvedic crude drug.

Five new flavonoid C-glucosides, 6-hydroxy-2-(4-hydroxybenzyl)-benzofuran-7-C-beta-d-glucopyranoside (1), 3-(alpha-methoxy-4-hydroxybenzylidene)-6-hydroxybenzo-2(3H)-furanone-7-C-beta-d-glucopyranoside (2), 2-hydroxy-2-p-hydroxybenzyl-3(2H)-6-hydroxybenzofuranone-7-C-beta-d-glucopyranoside (4), 8-(C-beta-d-glucopyranosyl)-7,3',4'-trihydroxyflavone (5) and 1,2-bis(2,4-dihydroxy,3-C-glucopyranosyl)-ethanedione (6) and two known compounds C-beta-d-glucopyranosyl-2,6-dihydroxyl benzene (7) and sesquiterpene (8), were isolated from an aqueous extract of the heartwood of Pterocarpus marsupium. The structure has been established using spectroscopic data.

Flavonoids↗
PubMed2004

Coumaroyl triterpene lactone, phenolic and naphthalene glycoside from stem bark of Diospyros angustifolia.

From the ethanolic extract of stem bark of D. angustifolia three new compounds, a coumaroyl triterpene lactone, diospyrosooleanolide (1), a phenolic glycoside, diospyrososide (2) and a naphthalene glycoside, diospyrosonaphthoside (3) were isolated along with five known compounds (4-8). The structures of these compounds were established on the basis of spectroscopic and chemical evidences.

Diospyros↗