Andrographolide (AG) is a diterpenoid lactone isolated from the leaves of Andrographis paniculata... more Andrographolide (AG) is a diterpenoid lactone isolated from the leaves of Andrographis paniculata. AG is a potent and low-toxicity antileishmanial agent. Chemotherapy applications of AG are, however, seriously constrained because of poor bioavailability, short plasma half-life, and inappropriate tissue localization. Nanoparticulation of AG was therefore envisaged as a possible solution. AG nanoparticles (AGnp) loaded in 50:50 poly(DL-lactide-co-glycolic acid) were prepared for delivery into the monocyte-macrophage cells infested with the amastigote form of leishmanial parasite for evaluation in the chemotherapy of leishmaniasis. Particle characteristics of AGnp were optimized by proportionate application of a stabilizer, polyvinyl alcohol (PVA). Physicochemical characterization of AGnp by photon correlation spectroscopy exhibited an average particle size of 173 nm and zeta potential of-34.8 mV. Atomic force microscopy visualization revealed spherical nanoparticles with a smooth surface. Antileishmanial activity was found to be significant for the nanoparticle preparation with 4% PVA (IC 50 34 µM) in about one-fourth of the dosage of the pure compound AG (IC 50 160 µM). AGnp therefore have significant potential to target the infested macrophage cells and prove valuable in chemotherapy of neglected tropical diseases such as leishmaniasis.
Phytoestrogens have been explored as promising next generation estrogenic drug candidates with mi... more Phytoestrogens have been explored as promising next generation estrogenic drug candidates with minimum cardiovascular risks. Investigating spatial, electronic and topological properties of the molecules, structure-activity relationships were drawn in an endeavor to find out the basic pharmacophore features of flavonoids for binding with the estrogen receptor. Implementing multi-parameter linear regression analysis, a significant relationship (R 2 Z0.892 and Q 2 Z0.805 for nZ19) was established that explained 86.097% variance in binding affinity to the receptor. This study revealed the importance of partial charges at atoms C 2 0 and C 4 0 in the phenyl ring C, electrotoplogical state of atom C 7 in the phenyl ring A and the molecular orientation and conformational stringency factors. It has been found that substitution by an e K donating group in the phenyl ring at C 2 0 , e K withdrawing groups at C 4 0 and C 7 of the molecule in conjunction with minimal conformational rigidity could be important for estrogenic activity.
Gold nanoparticles (Aunp) through biogenetic processes have induced enormous interest for lower t... more Gold nanoparticles (Aunp) through biogenetic processes have induced enormous interest for lower toxicity and precise applications. A rapid, one pot synthesis for uniformly sized gold nanoparticles was developed using polyphenolic compound quercetin. Reduction process was followed at low temperatures in a simple bath type sonicator. Nanoparticle plasmon response was recorded at 540 nm and the average size in TEM was observed at 15.07 nm. Detailed X-ray diffraction (XRD) observations proved fcc crystalline structure of metallic gold and the Fourier transform infrared (FTIR) analysis has confirmed nanoparticles conjugation with quercetin. Leishmaniasis, is a neglected tropical disease (NTD) classified by the World Health Organization (WHO). The leishmanial parasite multiply in host macrophages and most strains have developed drug resistance to available chemotherapeutics. Drug delivery is therefore a major problem in macrophage specific leishmanial parasite infections. New quercetin conjugated gold nanoparticles (QAunp) were successfully evaluated for the first time against leishmanial macrophage infections. Antileishmanial efficiency of QAunp was established against wild type (IC 50 15 ± 3), sodium stibogluconate resistant strain (IC 50 40 ± 8) and the paramomycin resistant (IC 50 30 ± 6) strains. Macrophage uptake of QAunp was complete within an hour as observed in TEM experiments.
This work was aimed to develop water resistant biocide film from renewable resources for applicat... more This work was aimed to develop water resistant biocide film from renewable resources for applications in food and water technology. Guar gum, a polymeric galactomannan, was intrinsically modified to a new guar gum benzamide. Benzoylation was carried out by benzoyl chloride reaction in water medium and a propyl amine spacer was used to impart a high degree of hydrophobicity. The new guar gum benzamide was resistant to water and soluble in non aqueous solvent like dimethyl sulfoxide. Cast films of thickness 0.162 mm had a breaking point tensile strength of 21.95 Mpa. The water vapor permeability of biomaterial film was 0.28 g mm kPa À1 h À1 m À2 and water contact angle on evaporative surface was 90.35 degree. Qualitative and quantitative biocide activity of film was established against Salmonella enterica, Escherichia coli, Staphylococcus aureus and Bacillus subtilis. The new guar gum benzamide absorbed strongly in UV region.
A cost competitive biomaterial for widespread applications in food and water technology is an urg... more A cost competitive biomaterial for widespread applications in food and water technology is an urgent need. We report a new hydrophobic biomaterial film for soluble pollutant sorption and reduction of microbial load in water environment. Guar gum from the seeds of Cyamopsis tetragonolobus was hydrophobically modified following benzoyl chloride reaction in aqueous alkali. The new biopolymer derivative is insoluble in water and form castable films with a high degree of surface hydrophobicity. The film water vapor permeability was 0.233 ± 0.029 g mm kPa À1 h À1 m À2 and the tensile property was 38.65 ± 3.66 MPa. The film surface contact angle against water was 77.36 ± 1.09°. The new biomaterial film demonstrated strong antimicrobial contact killing against both gram positive and gram negative bacteria. It also act as an efficient sorbent for a range of water soluble organic pollutants.
Considering the worth of developing non-steroidal estrogen analogues, the present research explor... more Considering the worth of developing non-steroidal estrogen analogues, the present research explores the pharmacophores of 1-trifluoromethyl-1,2,2-triphenylethylenes (Fig. 1) for post-coital antifertility activity using electrotopological state atom (E-state) index. The study shows the efficacy of Estate index in developing statistically acceptable model, which explains the electronic environment and topological states of different atoms in a molecule. The exploration concluded that phenyl ring attached to an ethylenic moiety, para substitution by nucleophilic group on the phenyl ring and presence of strong electronegative group as the 4th substituent on the 1st carbon of the ethylenic moiety might be crucial for activity.
Documented ethno-contraceptive use of Tape-vine or Stephania japonica (THUNB.) MIERS., Syn. Steph... more Documented ethno-contraceptive use of Tape-vine or Stephania japonica (THUNB.) MIERS., Syn. Stephania hernandifolia (WILLD.) WALP. leaves is evaluated with regards to post-coital pregnancy interceptive activity of its aqueous extract (AE) and an ethnomedicinal formulation (EF) in Wistar rats. EF at 500 and 250 mg/kg doses induced 66.7% and 33.3% post-coital pregnancy interception respectively and the higher dose exhibited significant reduction in number of litters born and also anti-implantation property. In contrast, none of the dose levels of AE interfered in pregnancy but significant anti-implantation property was observed at doses of 2 and 1 g/kg, even as the higher dose produced significant reduction in number of litters born as well. EF at 500 mg/kg also exhibited significant uterotrophic activity and histological changes in uterus. Pair-wise comparison of sex hormonelevels exhibited significant increment in serum estradiol, LH and FSH but decrease in progesterone levels. Assessed blood lipid-carbohydrate profile exhibited substantial decrease in glucose, cholesterol, VLDL and triglyceride contents and significant increase in HDL. It is concluded that EF probably acts as better post-coital pregnancy interceptive agent through restriction of implantation by alteration of gonadal hormone levels and decline in blood-glucose levels that possibly disrupts oxidative energy metabolism in uterus during implantation. High surge in LH and FSH suggests negligible interference in ovulatory mechanism. This preparation also seems to be free of cardiovascular risk factors. HPTLC and HPLC analysis of both EF and AE exhibited marked chemical differences.
Estrogens, a group of steroid hormones, act primarily by regulating gene expression after binding... more Estrogens, a group of steroid hormones, act primarily by regulating gene expression after binding with estrogen receptor (ER), a nuclear ligand-activated transcription factor, translocates to the nucleus after dimer formation, enhances the gene transcription. Estrogen Receptor Modulators (ERMs) have selective agonist and antagonist effects to different tissues, and the purpose of research on ERMs is to identify new potent and less toxic drug molecules. The present study has been focused on finding the structural requirements of ER ligand, using receptor-independent pharmacophore space modeling studies that can explore 3D structural features and configurations, responsible for the biological activity of structurally diverse compounds. The studies show (R,549.0؍ RMSD,681.2؍ D Dcost)453.776؍ the importance of hydrogen bond acceptors in the aromatic rings and a planner hydrophobic region in the molecular architecture along with critical geometrical distance between features are effectively crucial for binding with ER.
Please note that technical editing may introduce minor changes to the text and/or graphics, which... more Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal's standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains.
Andrographolide (AG) is a diterpenoid lactone isolated from the leaves of Andrographis paniculata... more Andrographolide (AG) is a diterpenoid lactone isolated from the leaves of Andrographis paniculata. AG is a potent and low-toxicity antileishmanial agent. Chemotherapy applications of AG are, however, seriously constrained because of poor bioavailability, short plasma half-life, and inappropriate tissue localization. Nanoparticulation of AG was therefore envisaged as a possible solution. AG nanoparticles (AGnp) loaded in 50:50 poly(DL-lactide-co-glycolic acid) were prepared for delivery into the monocyte-macrophage cells infested with the amastigote form of leishmanial parasite for evaluation in the chemotherapy of leishmaniasis. Particle characteristics of AGnp were optimized by proportionate application of a stabilizer, polyvinyl alcohol (PVA). Physicochemical characterization of AGnp by photon correlation spectroscopy exhibited an average particle size of 173 nm and zeta potential of-34.8 mV. Atomic force microscopy visualization revealed spherical nanoparticles with a smooth surface. Antileishmanial activity was found to be significant for the nanoparticle preparation with 4% PVA (IC 50 34 µM) in about one-fourth of the dosage of the pure compound AG (IC 50 160 µM). AGnp therefore have significant potential to target the infested macrophage cells and prove valuable in chemotherapy of neglected tropical diseases such as leishmaniasis.
Phytoestrogens have been explored as promising next generation estrogenic drug candidates with mi... more Phytoestrogens have been explored as promising next generation estrogenic drug candidates with minimum cardiovascular risks. Investigating spatial, electronic and topological properties of the molecules, structure-activity relationships were drawn in an endeavor to find out the basic pharmacophore features of flavonoids for binding with the estrogen receptor. Implementing multi-parameter linear regression analysis, a significant relationship (R 2 Z0.892 and Q 2 Z0.805 for nZ19) was established that explained 86.097% variance in binding affinity to the receptor. This study revealed the importance of partial charges at atoms C 2 0 and C 4 0 in the phenyl ring C, electrotoplogical state of atom C 7 in the phenyl ring A and the molecular orientation and conformational stringency factors. It has been found that substitution by an e K donating group in the phenyl ring at C 2 0 , e K withdrawing groups at C 4 0 and C 7 of the molecule in conjunction with minimal conformational rigidity could be important for estrogenic activity.
Gold nanoparticles (Aunp) through biogenetic processes have induced enormous interest for lower t... more Gold nanoparticles (Aunp) through biogenetic processes have induced enormous interest for lower toxicity and precise applications. A rapid, one pot synthesis for uniformly sized gold nanoparticles was developed using polyphenolic compound quercetin. Reduction process was followed at low temperatures in a simple bath type sonicator. Nanoparticle plasmon response was recorded at 540 nm and the average size in TEM was observed at 15.07 nm. Detailed X-ray diffraction (XRD) observations proved fcc crystalline structure of metallic gold and the Fourier transform infrared (FTIR) analysis has confirmed nanoparticles conjugation with quercetin. Leishmaniasis, is a neglected tropical disease (NTD) classified by the World Health Organization (WHO). The leishmanial parasite multiply in host macrophages and most strains have developed drug resistance to available chemotherapeutics. Drug delivery is therefore a major problem in macrophage specific leishmanial parasite infections. New quercetin conjugated gold nanoparticles (QAunp) were successfully evaluated for the first time against leishmanial macrophage infections. Antileishmanial efficiency of QAunp was established against wild type (IC 50 15 ± 3), sodium stibogluconate resistant strain (IC 50 40 ± 8) and the paramomycin resistant (IC 50 30 ± 6) strains. Macrophage uptake of QAunp was complete within an hour as observed in TEM experiments.
This work was aimed to develop water resistant biocide film from renewable resources for applicat... more This work was aimed to develop water resistant biocide film from renewable resources for applications in food and water technology. Guar gum, a polymeric galactomannan, was intrinsically modified to a new guar gum benzamide. Benzoylation was carried out by benzoyl chloride reaction in water medium and a propyl amine spacer was used to impart a high degree of hydrophobicity. The new guar gum benzamide was resistant to water and soluble in non aqueous solvent like dimethyl sulfoxide. Cast films of thickness 0.162 mm had a breaking point tensile strength of 21.95 Mpa. The water vapor permeability of biomaterial film was 0.28 g mm kPa À1 h À1 m À2 and water contact angle on evaporative surface was 90.35 degree. Qualitative and quantitative biocide activity of film was established against Salmonella enterica, Escherichia coli, Staphylococcus aureus and Bacillus subtilis. The new guar gum benzamide absorbed strongly in UV region.
A cost competitive biomaterial for widespread applications in food and water technology is an urg... more A cost competitive biomaterial for widespread applications in food and water technology is an urgent need. We report a new hydrophobic biomaterial film for soluble pollutant sorption and reduction of microbial load in water environment. Guar gum from the seeds of Cyamopsis tetragonolobus was hydrophobically modified following benzoyl chloride reaction in aqueous alkali. The new biopolymer derivative is insoluble in water and form castable films with a high degree of surface hydrophobicity. The film water vapor permeability was 0.233 ± 0.029 g mm kPa À1 h À1 m À2 and the tensile property was 38.65 ± 3.66 MPa. The film surface contact angle against water was 77.36 ± 1.09°. The new biomaterial film demonstrated strong antimicrobial contact killing against both gram positive and gram negative bacteria. It also act as an efficient sorbent for a range of water soluble organic pollutants.
Considering the worth of developing non-steroidal estrogen analogues, the present research explor... more Considering the worth of developing non-steroidal estrogen analogues, the present research explores the pharmacophores of 1-trifluoromethyl-1,2,2-triphenylethylenes (Fig. 1) for post-coital antifertility activity using electrotopological state atom (E-state) index. The study shows the efficacy of Estate index in developing statistically acceptable model, which explains the electronic environment and topological states of different atoms in a molecule. The exploration concluded that phenyl ring attached to an ethylenic moiety, para substitution by nucleophilic group on the phenyl ring and presence of strong electronegative group as the 4th substituent on the 1st carbon of the ethylenic moiety might be crucial for activity.
Documented ethno-contraceptive use of Tape-vine or Stephania japonica (THUNB.) MIERS., Syn. Steph... more Documented ethno-contraceptive use of Tape-vine or Stephania japonica (THUNB.) MIERS., Syn. Stephania hernandifolia (WILLD.) WALP. leaves is evaluated with regards to post-coital pregnancy interceptive activity of its aqueous extract (AE) and an ethnomedicinal formulation (EF) in Wistar rats. EF at 500 and 250 mg/kg doses induced 66.7% and 33.3% post-coital pregnancy interception respectively and the higher dose exhibited significant reduction in number of litters born and also anti-implantation property. In contrast, none of the dose levels of AE interfered in pregnancy but significant anti-implantation property was observed at doses of 2 and 1 g/kg, even as the higher dose produced significant reduction in number of litters born as well. EF at 500 mg/kg also exhibited significant uterotrophic activity and histological changes in uterus. Pair-wise comparison of sex hormonelevels exhibited significant increment in serum estradiol, LH and FSH but decrease in progesterone levels. Assessed blood lipid-carbohydrate profile exhibited substantial decrease in glucose, cholesterol, VLDL and triglyceride contents and significant increase in HDL. It is concluded that EF probably acts as better post-coital pregnancy interceptive agent through restriction of implantation by alteration of gonadal hormone levels and decline in blood-glucose levels that possibly disrupts oxidative energy metabolism in uterus during implantation. High surge in LH and FSH suggests negligible interference in ovulatory mechanism. This preparation also seems to be free of cardiovascular risk factors. HPTLC and HPLC analysis of both EF and AE exhibited marked chemical differences.
Estrogens, a group of steroid hormones, act primarily by regulating gene expression after binding... more Estrogens, a group of steroid hormones, act primarily by regulating gene expression after binding with estrogen receptor (ER), a nuclear ligand-activated transcription factor, translocates to the nucleus after dimer formation, enhances the gene transcription. Estrogen Receptor Modulators (ERMs) have selective agonist and antagonist effects to different tissues, and the purpose of research on ERMs is to identify new potent and less toxic drug molecules. The present study has been focused on finding the structural requirements of ER ligand, using receptor-independent pharmacophore space modeling studies that can explore 3D structural features and configurations, responsible for the biological activity of structurally diverse compounds. The studies show (R,549.0؍ RMSD,681.2؍ D Dcost)453.776؍ the importance of hydrogen bond acceptors in the aromatic rings and a planner hydrophobic region in the molecular architecture along with critical geometrical distance between features are effectively crucial for binding with ER.
Please note that technical editing may introduce minor changes to the text and/or graphics, which... more Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal's standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains.
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