http://nopr.niscair.res.in/handle/123456789/70 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/103 Title: Quantitative structure-activity relationship study of orally active cyclooxygenase-2 (COX-2) inhibitors of derivatives of 3-phenoxypyran-4-one <br/> <br/>Authors: Shekhawat, Manju; Singh, P; Kumar, R <br/> <br/>Abstract: The cyclooxygenase (COX) inhibition activities of the derivatives of 3-phenoxypyran-4-one were analyzed through multiple-regression analysis (MRA). Appropriate physicochemical parameters, identified for the substitutents of phenyl ring, attached to 3-phenoxypyran-4-one moiety were quantitatively correlated with COX-2 and COX-1 inhibition activities of these compounds. The derived significant correlation equation for COX-2 inhibition suggested that the ortho-substituent with negative resonance parameter, the para-substituent with lower dipole moment and the meta-substituent having higher resonance parameter were advantageous for the activity. The derived correlation equation for COX-1 inhibition suggested the significance of resonance effect for ortho-substituents and electron-donating effect for para-substituent. A few potential congeners were also suggested for further synthesis. <br/> <br/>Page(s): 50-55 Mon, 29 Jan 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/93 Title: Extraction of bioactive principles from Mucuna pruriens seeds <br/> <br/>Authors: Misra, Laxminarain; Wagner, Hildebert <br/> <br/>Abstract: Mucuna pruriens (L.) DC. Syn. M. prurita Hook. (Papiliona-ceae) is used in male impotency, as aphrodisiac, in sexual debility, and as nervine tonic. It also possesses anti-parkinson property, possibly due to the presence of L-DOPA. In the present study, attempts were made to develop the suitable method(s) for extrac-tion of L-DOPA/other active components from the seeds using different solvents. The various extracts were also screened for their neuroprotective and antioxidant activities. In addition, TLC and HPLC fingerprinting of the extracts for amino acid compo-nents were also developed for preliminary and sophisticated analysis. The L-DOPA could be obtained in good yield on extrac-tion with EtOH-H2O mixture (1:1) using ascorbic acid as protec-tor. Interestingly, n-propanol extract, which contained negligible amount of L-DOPA, had shown significant neuroprotective activ-ity, suggesting that some components, other than L-DOPA, might also be responsible for anti-Parkinson property of seeds. The ex-tract (MW-0100) containing mainly amino acids and water-ethanol extract (1:1) (MWEL-1299) showed promising antioxi-dant activity (EC Sub(50) = 2.5 μg) against DPPH radicals. MWEL-1299 also exhibited encouraging results against 1-methyl-4-phenylpyridinium ion (MPP+) toxicity. The TLC fingerprinting may be used to authenticate the plant material in herbal industry. <br/> <br/>Page(s): 56-60 Mon, 29 Jan 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/92 Title: Conformation of an octapeptide fragment (2-9) of kaliocin-1 in DMSO-d₆ by ¹H NMR and restrained molecular dynamics <br/> <br/>Authors: Sunilkumar, P N; Sadasivan, C; Devaky, K S; Haridas, M <br/> <br/>Abstract: Kaliocin-1, a 31-residue synthetic peptide (FFSASCVPGADKGQFPNLCRLCA GTGENKCA), which has shown the antimicrobial activity forms the 152-182 fragment of human lactoferrin (HLf). As the octapeptide FSASCVPG forms the 2-9 fragment of kaliocin-1, in the present study, its conformation in dimethyl sulfoxide-d₆ (DMSO-d₆) has been determined using two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy as well as restrained molecular dynamics. Sequence specific assignments of all the ¹H resonances have been carried out using 2D correlation experiments (2D DQF-COSY, TOCSY and ROESY). In dimethyl sulfoxide-d₆ at 25ºC, the octapeptide adopts a predominantly extended backbone conformation. The calculated structure resembles closely with the reported structure of the corresponding fragment of HLf. The peptide also has sequence and structural similarity with the corresponding fragments of lactoferrins from other organisms.Kaliocin-1, a 31-residue synthetic peptide (FFSASCVPGADKGQFPNLCRLCA GTGENKCA), which has shown the antimicrobial activity forms the 152-182 fragment of human lactoferrin (HLf). As the octapeptide FSASCVPG forms the 2-9 fragment of kaliocin-1, in the present study, its conformation in dimethyl sulfoxide-d₆ (DMSO-d₆) has been determined using two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy as well as restrained molecular dynamics. Sequence specific assignments of all the ¹H resonances have been carried out using 2D correlation experiments (2D DQF-COSY, TOCSY and ROESY). In dimethyl sulfoxide-d₆ at 25ºC, the octapeptide adopts a predominantly extended backbone conformation. The calculated structure resembles closely with the reported structure of the corresponding fragment of HLf. The peptide also has sequence and structural similarity with the corresponding fragments of lactoferrins from other organisms. <br/> <br/>Page(s): 44-49 Mon, 29 Jan 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/91 Title: Kinetic properties and storage stability of catalase immobilized on to florisil <br/> <br/>Authors: Ozyilmaz, Gul; Tukel, S Seyhan; Alptekin, Ozlem <br/> <br/>Abstract: The covalent immobilization of bovine liver catalase (CAT) on to florisil via glutaraldehyde was investigated. Optimum immobilization pH and temperature were determined as pH 6.0, 10°C respectively, while the amount of initial CAT per g of carrier and immobilization time was determined as 5 mg g⁻¹ and 120 min, respectively. The Vmax values for free and immobilized CAT were found to be 1.7 × 10⁵ and 2.0 × 10⁴ μmol H₂O₂. min⁻¹ mg protein⁻¹, respectively, whereas KM values were 33.3 mM and 1722.0 mM respectively. Operational stability was determined by using a stirred batch-type column reactor. Immobilized CAT retained about 40% of its initial activity after 50 uses. It showed higher storage stability than free CAT at 4°C and 25°C. Its storage stability increased with increasing relative humidity (RH) from 0 to 20% of the medium. The highest storage stability was obtained in 20% RH, however, further increase in RH from 40 to 100% significantly decreased the storage stability. <br/> <br/>Page(s): 38-43 Mon, 29 Jan 2007 22:58:59 GMT