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Maria Luiza Vilela Oliva - One of the best experts on this subject based on the ideXlab platform.
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effect of Bauhinia bauhinioides kallikrein inhibitor on endothelial proliferation and intracellular calcium concentration
European Review for Medical and Pharmacological Sciences, 2014Co-Authors: Mehmet Bilgin, Maria Luiza Vilela Oliva, K M Burgazli, A Rafiq, M Mericliler, C Neuhof, Mariana S Parahuleva, Nedim Soydan, O Doerr, Yaser AbdallahAbstract:OBJECTIVES : Proteinase inhibitors act as a defensive system against predators e.g. in - sects, in plants. Bauhinia bauhinioides kallikrein inhibitor (BbKI) is a serine proteinase inhibitor, iso - lated from seeds of Bauhinia bauhinioides and is structurally similar to plant Kunitz-type inhibitors but lacks disulfide bridges. In this study we evalu - ated the antiproliferative effect of BbKI on endothe - lial cells and its impact on changes in membrane potential and intracellular calcium. MATERIALS AND METHODS: HUVEC prolifer - ation was significantly reduced by incubation with BbKI 50 and 100 µM 12% and 13%. Further - more, BbKI (100 µM) exposure caused a signifi - cant increase in intracellular Ca 2+ concentration by 35% as compared to untreated control. RESULTS: The intracellular rise in calcium was not affected by the absence of extracellular cal - cium. BBKI also caused a significant change in the cell membrane potential but the antiprolifera - tive effect was independent of changes in mem - brane potential. CONCLUSIONS: BBKI has an antiproliferative effect on HUVEC, which is independent of the changes in membrane potential, and it causes an increase in intracellular Ca 2+ .
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blocking the proliferation of human tumor cell lines by peptidase inhibitors from Bauhinia seeds
Planta Medica, 2013Co-Authors: Adriana Miti Nakahata, Misako U. Sampaio, Barbara Mayer, Peter Neth, Daiane Hansen, Maria Luiza Vilela OlivaAbstract:In cancer tumors, growth, invasion, and formation of metastasis at a secondary site play a pivotal role, participating in diverse processes in the development of the pathology, such as degradation of extracellular matrix. Bauhinia seeds contain relatively large quantities of peptidase inhibitors, and two Bauhinia inhibitors were obtained in a recombinant form from the Bauhinia bauhinioides species, B. bauhinoides cruzipain inhibitor, which is a cysteine and serine peptidase inhibitor, and B. bauhinioides kallikrein inhibitor, which is a serine peptidase inhibitor. While recombinant B. bauhinoides cruzipain inhibitor inhibits human neutrophil elastase cathepsin G and the cysteine proteinase cathepsin L, recombinant B. bauhinioides kallikrein inhibitor inhibits plasma kallikrein and plasmin. The effects of recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor on the viability of tumor cell lines with a distinct potential of growth from the same tissue were compared to those of the clinical cytotoxic drug 5-fluorouracil. At 12.5 µM concentration, recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor were more efficient than 5-fluorouracil in inhibiting MKN-28 and Hs746T (gastric), HCT116 and HT29 (colorectal), SkBr-3 and MCF-7 (breast), and THP-1 and K562 (leukemia) cell lines. Additionally, recombinant B. bauhinoides cruzipain inhibitor inhibited 40 % of the migration of Hs746T, the most invasive gastric cell line, while recombinant B. bauhinioides kallikrein inhibitor did not affect cell migration. Recombinant B. bauhinioides kallikrein inhibitor and recombinant B. bauhinoides cruzipain inhibitor, even at high doses, did not affect hMSC proliferation while 5-fluorouracil greatly reduced the proliferation rates of hMSCs. Therefore, both recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor might be considered for further studies to block peptidase activities in order to target specific peptidase-mediated growth and invasion characteristics of individual tumors, mainly in patients resistant to 5-fluorouracil chemotherapy.
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purification primary structure and potential functions of a novel lectin from Bauhinia forficata seeds
Process Biochemistry, 2012Co-Authors: Mariana Cristina Cabral Silva, Misako U. Sampaio, Reinhart Mentele, Lucimeire A Santana, Rodrigo Da Silva Ferreira, Antonio Miranda, Rosemeire A Silvalucca, Maria Tereza Dos Santos Correia, Maria Luiza Vilela OlivaAbstract:Abstract A new lectin, BfL, was purified from Bauhinia forficata seeds by ammonium sulfate fractionation, DEAE-Sephadex ion exchange chromatography, Sepharose-4B and chitin affinity chromatographies and Superdex 75 size exclusion chromatography. The molecular homogeneity and purity of BfL were assessed by reversed-phase HPLC. BfL appeared as a single band of approximately 27.0 kDa on SDS-PAGE under non-reducing and reducing conditions, and its molecular weight was determined to be 27,850 Da by LC/ESI-MS. BfL is a glycoprotein with a carbohydrate content of 6.24% determined by the phenol–sulfuric acid method. Fetuin, asialofetuin, thyroglobulin and azocasein inhibited the hemagglutinating activity of BfL, whereas saccharides did not. BfL hemagglutinating activity was stable at 100 °C for 30 min, pH-dependent, with the highest activity at pH 6.0, and metal-independent. The primary structure of BfL shows similarity with other lectins from the genus Bauhinia . Deconvolution of the BfL circular dichroism (CD) spectrum indicated the presence of α-helix and β structures. BfL increases coagulation time, but this effect is not related to human plasma kallikrein or human factor Xa inhibition. BfL also inhibits ADP- and epinephrine-induced platelet aggregation in a dose-dependent manner and is the only currently described lectin from Bauhinia that exhibits anticoagulant and antiplatelet aggregating properties.
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Bauhinia bauhinioides plasma kallikrein inhibitor interaction with synthetic peptides and fluorogenic peptide substrates related to the reactive site sequence
Current Medicinal Chemistry, 2001Co-Authors: Maria Luiza Vilela Oliva, Misako U. Sampaio, C R Mendes, E M Santomaurovaz, Maria A Juliano, Reinhart Mentele, Ennes A Auerswald, C A M SampaioAbstract:A serine proteinase inhibitor was purified from Bauhinia bauhinioides seeds after extraction with 0.15M NaCl by ion-exchange column chromatography on DEAE-Sephadex, gel filtration on Superose 12 column, Mono Q chromatography or alternatively by affinity chromatography on trypsin- Sepharose. The inhibitor is a single polypeptide chain with molecular mass 20 kDa by gel filtration on Superose 12, but was resolved into two peaks by ion - exchange chromatography on Mono Q (FPLC system). The main eluted peak inhibits trypsin (Ki = 0.6 nM), plasma kallikrein (Ki = 0.35 nM), plasmin (Ki = 33.1 nM), and weakly chymotrypsin (Ki = 2,700 nM), being the most effective plasma kallikrein inhibitor isolated from Bauhinia seeds. Therefore, it was denominated Bauhinia bauhinioides kallikrein inhibitor (BbKI). Activity is thermolabile and on trypsin inhibition optimum pH is 8.0. BbKI displays high homology to other plant Kunitz inhibitors, except for the absence of disulfide bridges, and the only cysteine residue is at the C-terminal position (residue 154) characterizes a distinct member of the Kunitz family. The affinity of the inhibitor to trypsin was confirmed by adsorption to trypsin-Sepharose resin and by isolation of the trypsin-inhibitor complex by gel filtration. Peptides with variations around the reactive site of BbKI (GLPVRFESPLRINIIKESY) were synthesized containing a quenched fluorogenic group. Trypsin but not plasma kallikrein substrates, these peptides strongly inhibited plasma kallikrein.
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human plasma kallikrein and tissue kallikrein binding to a substrate based on the reactive site of a factor xa inhibitor isolated from Bauhinia ungulata seeds
Immunopharmacology, 1999Co-Authors: Maria Luiza Vilela Oliva, Misako U. Sampaio, Maria A Juliano, Ennes A Auerswald, Sonia A De Andrade, Isabel De Fatima Correia Batista, Hans Fritz, Claudio A M SampaioAbstract:Kunitz type Bauhinia ungulata factor Xa inhibitor (BuXI) was purified from B. ungulata seeds. BuXI inactivates factor Xa and human plasma kallikrein (HuPK) with K i values of 18.4 and 6.9 nM, respectively. However, Bauhinia variegata trypsin inhibitor (BvTI) which is 70% homologous to BuXI does not inhibit factor Xa and is less efficient on HuPK (K i = 80 nM). The comparison between BuXI and BvTI reactive site structure indicates differences at Met 59 , Thr 66 and Met 67 residues. The hydrolysis rate of quenched fluorescence peptide substrates based on BuXI reactive site sequence, Abz-VMIAALPRTMFIQ-EDDnp (leading peptide), by HuPK and porcine pancreatic kallikrein (PoPK) is low, but hydrolysis is enhanced with Abz-VMIAALPRTMQ-EDDnp, derived from the leading peptide shortened by removing the dipeptide Phe-Ileu from the C-terminal portion, for HuPK (K m = 0.68 μM, k cat /K m = 1.3 × 10 6 M - 1 s -1 ), and the shorter substrate Abz-LPRTMQ-EDDnp is better for PoPK (K m = 0.66 μM, k cat /K m = 2.2 × 10 3 M - 1 s -1 ). The contribution of substrate methionine residues to HuPK and PoPK hydrolysis differs from that observed with factor Xa. The determined K m and k cat values suggest that the substrates interact with kallikreins the same as an enzyme and inhibitor interacts to form complexes.
Misako U. Sampaio - One of the best experts on this subject based on the ideXlab platform.
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blocking the proliferation of human tumor cell lines by peptidase inhibitors from Bauhinia seeds
Planta Medica, 2013Co-Authors: Adriana Miti Nakahata, Misako U. Sampaio, Barbara Mayer, Peter Neth, Daiane Hansen, Maria Luiza Vilela OlivaAbstract:In cancer tumors, growth, invasion, and formation of metastasis at a secondary site play a pivotal role, participating in diverse processes in the development of the pathology, such as degradation of extracellular matrix. Bauhinia seeds contain relatively large quantities of peptidase inhibitors, and two Bauhinia inhibitors were obtained in a recombinant form from the Bauhinia bauhinioides species, B. bauhinoides cruzipain inhibitor, which is a cysteine and serine peptidase inhibitor, and B. bauhinioides kallikrein inhibitor, which is a serine peptidase inhibitor. While recombinant B. bauhinoides cruzipain inhibitor inhibits human neutrophil elastase cathepsin G and the cysteine proteinase cathepsin L, recombinant B. bauhinioides kallikrein inhibitor inhibits plasma kallikrein and plasmin. The effects of recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor on the viability of tumor cell lines with a distinct potential of growth from the same tissue were compared to those of the clinical cytotoxic drug 5-fluorouracil. At 12.5 µM concentration, recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor were more efficient than 5-fluorouracil in inhibiting MKN-28 and Hs746T (gastric), HCT116 and HT29 (colorectal), SkBr-3 and MCF-7 (breast), and THP-1 and K562 (leukemia) cell lines. Additionally, recombinant B. bauhinoides cruzipain inhibitor inhibited 40 % of the migration of Hs746T, the most invasive gastric cell line, while recombinant B. bauhinioides kallikrein inhibitor did not affect cell migration. Recombinant B. bauhinioides kallikrein inhibitor and recombinant B. bauhinoides cruzipain inhibitor, even at high doses, did not affect hMSC proliferation while 5-fluorouracil greatly reduced the proliferation rates of hMSCs. Therefore, both recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor might be considered for further studies to block peptidase activities in order to target specific peptidase-mediated growth and invasion characteristics of individual tumors, mainly in patients resistant to 5-fluorouracil chemotherapy.
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purification primary structure and potential functions of a novel lectin from Bauhinia forficata seeds
Process Biochemistry, 2012Co-Authors: Mariana Cristina Cabral Silva, Misako U. Sampaio, Reinhart Mentele, Lucimeire A Santana, Rodrigo Da Silva Ferreira, Antonio Miranda, Rosemeire A Silvalucca, Maria Tereza Dos Santos Correia, Maria Luiza Vilela OlivaAbstract:Abstract A new lectin, BfL, was purified from Bauhinia forficata seeds by ammonium sulfate fractionation, DEAE-Sephadex ion exchange chromatography, Sepharose-4B and chitin affinity chromatographies and Superdex 75 size exclusion chromatography. The molecular homogeneity and purity of BfL were assessed by reversed-phase HPLC. BfL appeared as a single band of approximately 27.0 kDa on SDS-PAGE under non-reducing and reducing conditions, and its molecular weight was determined to be 27,850 Da by LC/ESI-MS. BfL is a glycoprotein with a carbohydrate content of 6.24% determined by the phenol–sulfuric acid method. Fetuin, asialofetuin, thyroglobulin and azocasein inhibited the hemagglutinating activity of BfL, whereas saccharides did not. BfL hemagglutinating activity was stable at 100 °C for 30 min, pH-dependent, with the highest activity at pH 6.0, and metal-independent. The primary structure of BfL shows similarity with other lectins from the genus Bauhinia . Deconvolution of the BfL circular dichroism (CD) spectrum indicated the presence of α-helix and β structures. BfL increases coagulation time, but this effect is not related to human plasma kallikrein or human factor Xa inhibition. BfL also inhibits ADP- and epinephrine-induced platelet aggregation in a dose-dependent manner and is the only currently described lectin from Bauhinia that exhibits anticoagulant and antiplatelet aggregating properties.
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Bauhinia bauhinioides plasma kallikrein inhibitor interaction with synthetic peptides and fluorogenic peptide substrates related to the reactive site sequence
Current Medicinal Chemistry, 2001Co-Authors: Maria Luiza Vilela Oliva, Misako U. Sampaio, C R Mendes, E M Santomaurovaz, Maria A Juliano, Reinhart Mentele, Ennes A Auerswald, C A M SampaioAbstract:A serine proteinase inhibitor was purified from Bauhinia bauhinioides seeds after extraction with 0.15M NaCl by ion-exchange column chromatography on DEAE-Sephadex, gel filtration on Superose 12 column, Mono Q chromatography or alternatively by affinity chromatography on trypsin- Sepharose. The inhibitor is a single polypeptide chain with molecular mass 20 kDa by gel filtration on Superose 12, but was resolved into two peaks by ion - exchange chromatography on Mono Q (FPLC system). The main eluted peak inhibits trypsin (Ki = 0.6 nM), plasma kallikrein (Ki = 0.35 nM), plasmin (Ki = 33.1 nM), and weakly chymotrypsin (Ki = 2,700 nM), being the most effective plasma kallikrein inhibitor isolated from Bauhinia seeds. Therefore, it was denominated Bauhinia bauhinioides kallikrein inhibitor (BbKI). Activity is thermolabile and on trypsin inhibition optimum pH is 8.0. BbKI displays high homology to other plant Kunitz inhibitors, except for the absence of disulfide bridges, and the only cysteine residue is at the C-terminal position (residue 154) characterizes a distinct member of the Kunitz family. The affinity of the inhibitor to trypsin was confirmed by adsorption to trypsin-Sepharose resin and by isolation of the trypsin-inhibitor complex by gel filtration. Peptides with variations around the reactive site of BbKI (GLPVRFESPLRINIIKESY) were synthesized containing a quenched fluorogenic group. Trypsin but not plasma kallikrein substrates, these peptides strongly inhibited plasma kallikrein.
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human plasma kallikrein and tissue kallikrein binding to a substrate based on the reactive site of a factor xa inhibitor isolated from Bauhinia ungulata seeds
Immunopharmacology, 1999Co-Authors: Maria Luiza Vilela Oliva, Misako U. Sampaio, Maria A Juliano, Ennes A Auerswald, Sonia A De Andrade, Isabel De Fatima Correia Batista, Hans Fritz, Claudio A M SampaioAbstract:Kunitz type Bauhinia ungulata factor Xa inhibitor (BuXI) was purified from B. ungulata seeds. BuXI inactivates factor Xa and human plasma kallikrein (HuPK) with K i values of 18.4 and 6.9 nM, respectively. However, Bauhinia variegata trypsin inhibitor (BvTI) which is 70% homologous to BuXI does not inhibit factor Xa and is less efficient on HuPK (K i = 80 nM). The comparison between BuXI and BvTI reactive site structure indicates differences at Met 59 , Thr 66 and Met 67 residues. The hydrolysis rate of quenched fluorescence peptide substrates based on BuXI reactive site sequence, Abz-VMIAALPRTMFIQ-EDDnp (leading peptide), by HuPK and porcine pancreatic kallikrein (PoPK) is low, but hydrolysis is enhanced with Abz-VMIAALPRTMQ-EDDnp, derived from the leading peptide shortened by removing the dipeptide Phe-Ileu from the C-terminal portion, for HuPK (K m = 0.68 μM, k cat /K m = 1.3 × 10 6 M - 1 s -1 ), and the shorter substrate Abz-LPRTMQ-EDDnp is better for PoPK (K m = 0.66 μM, k cat /K m = 2.2 × 10 3 M - 1 s -1 ). The contribution of substrate methionine residues to HuPK and PoPK hydrolysis differs from that observed with factor Xa. The determined K m and k cat values suggest that the substrates interact with kallikreins the same as an enzyme and inhibitor interacts to form complexes.
Dinesh Mohan - One of the best experts on this subject based on the ideXlab platform.
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Cadmium and lead remediation using magnetic and non-magnetic sustainable biosorbents derived from Bauhinia purpurea pods
RSC Advances, 2017Co-Authors: Rupa Sharma, Ankur Sarswat, Charles U Pittman, Dinesh MohanAbstract:Bauhinia purpurea (Kaniar) pods were dried, powdered, and utilized for cadmium and lead removal. Bauhinia purpurea (Kaniar) pod powders (KPP) were converted into magnetic Bauhinia purpurea (Kaniar) powders (MKPP) by co-precipitation. Iron(II) sulfate and iron(III) sulfate were used as iron precursors. The biosorbents were extensively characterized using zero point charge measurements (pHPZC), ultimate and proximate analyses, Fourier transform infrared (FTIR) and FT-Raman spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), BET surface area (SBET) measurements, physical properties measurement system (PPMS), scanning electron microscopy (SEM) and energy dispersive X-ray fluorescence (EDXRF) techniques. The SBET of MKPP (52.0 m2 g−1) was higher than KPP (1.8 m2 g−1). Optimum Cd2+ and Pb2+ removal by KPP and MKPP was obtained at pH 5.0 and 4.5, respectively. Metal–ligand chelation, ion-exchange and hydrogen bonding were possible mechanisms for Cd2+ and Pb2+ removal. KPP and MKPP showed maximum Langmuir adsorption capacities of 11.1 and 4.8 mg g−1 for Cd2+ and 16.4 and 14.1 for Pb2+, respectively. Lead and cadmium kinetic data were best described using a pseudo-second-order equation. Cd2+ and Pb2+ removal was affected by the presence of Cu2+ during adsorption from a multicomponent aqueous environment. Cd2+ and Pb2+ remediation from actual groundwater was demonstrated. Fixed-bed studies for Pb2+ removal by KPP were also performed with a column capacity of 18.8 mg g−1 (column dia 2.0 cm; column length 40 cm; bed height 6.0 cm; pH 4.5; flow rate 5.0 mL min−1; Pb2+ conc. 10 mg L−1). Spent KPP was regenerated using 0.1 N HCl. Approximately 85% of total Pb2+ recovery was achieved using 100 mL 0.1 N HCl.
J N Eloff - One of the best experts on this subject based on the ideXlab platform.
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the antimicrobial antioxidative anti inflammatory activity and cytotoxicity of different fractions of four south african Bauhinia species used traditionally to treat diarrhoea
Journal of Ethnopharmacology, 2012Co-Authors: Aroke Shahid Ahmed, E E Elgorashi, N Moodley, L J Mcgaw, Vinasan Naidoo, J N EloffAbstract:Abstract Ethnopharmacological importance Many Bauhinia species, including those indigenous to South Africa, are used in traditional medicine across the world for treating ailments such as gastrointestinal tract (GIT) disorders, diabetes, infectious diseases and inflammation. Aims Several relevant aspects of different fractions of leaf extracts of Bauhinia bowkeri (BAB), Bauhinia galpinii (BAG), Bauhinia petersiana (BAP), and Bauhinia variegata (BAV) used in South African traditional medicine to alleviate diarrhoea related symptoms were evaluated. Materials and Methods The antioxidative activities of the extracts were determined using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS + ) radical scavenging and ferric reducing antioxidant power (FRAP) methods. In vitro antimicrobial activities of the extracts were determined against bacterial strains ( Staphylococcus aureus , Pseudomonas aeruginosa , Escherichia coli and Enterococcus faecalis ) and clinical isolates of the opportunistic fungal strains ( Aspergillus fumigatus , Candida albicans , and Cryptococcus neoformans ) using a serial dilution microplate method. The polyphenolic contents were quantified using standard methods, and anti-inflammatory activities of the crude extracts were determined using the cyclooxygenase and soybean 15-lipoxygenase enzyme inhibitory assays. The safety of the extracts was evaluated by determining the cytotoxicity against Vero cell lines. Results The acidified 70% acetone crude extract and their fractions had good antiradical potency against the DPPH and ABTS radicals. The methanol soluble portions of the butanol fractions were more potent (EC 50 ranges from 0.64±0.05 to 1.51±0.07 and 0.88±0.18 to 1.49±0.09 μg/ml against DPPH and ABTS radical respectively) compared to the standard, trolox and ascorbic acid (EC 50 ranges from 1.47±0.24 to 1.70±0.27 μg/ml) for both DPPH and ABTS. The crude extracts contained variable quantities of phenolic content. The crude extracts and their fractions had weak to good antimicrobial activities, inhibiting the growth of the organisms at concentrations ranging from 39 to 2500 μg/ml. The BAG crude extract and its fractions were the most active against the fungi (MICs ranging from 39 to 625 μg/ml) while the BAB extract and its fractions were the least active with the MICs ranging between 39 and 2500 μg/ml. Aspergillus fumigatus was the least susceptible fungus while Cryptococcus neoformans was the most susceptible. The phenolic-rich crude extracts of BAB, BAG, and BAP had moderate to good dose-dependent cyclooxygenase-1 enzyme inhibitory activity with inhibitions between 22.8% and 71.4%. The extracts were however, inactive against cyclooxygenase-2. The extracts had some level of cytotoxicity towards Vero cell lines, reducing cell viability to less than 10% at concentrations more than 50 μg/ml. Conclusion The biological activities observed in Bauhinia species provide a scientific basis for the use of the plants in traditional medicines to treat diseases with multi-factorial pathogenesis such as diarrhoea, with each aspect of activity contributing to the ultimate therapeutic benefit of the plants. However, the use of the phenolic-rich extracts of these plants to treat diarrhoea or any other ailments in traditional medicine needs to be monitored closely because of potential toxic effects and selective inhibition of COX-1 with the associated GIT injury.
Madhu Sudhan V Reddy - One of the best experts on this subject based on the ideXlab platform.
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anti inflammatory activity of a novel flavonol glycoside from the Bauhinia variegata linn
Natural Product Research, 2003Co-Authors: R N Yadava, Madhu Sudhan V ReddyAbstract:Bauhinia variegata Linn. (Leguminosae) is commonly known as 'Kachnar' in Hindi. It is distributed almost throught India. Its powdered bark is traditionally used for tonic, astrain, ulcers. It is also useful in skin diseases. The roots are used as antidote to snake poison. The present article deals with the isolation and structural elucidation of a novel flavonol glycoside 5,7,3',4'-tetrahydroxy-3-methoxy-7- O - f - l -rhamnopyranosyl(1 M 3)- O - g - d -galactopyranoside ( 1 ) from the roots of Bauhinia Variegata and its structure was identified by spectral analysis and chemical degradations. The novel compound ( 1 ) showed anti-inflammatory activity.
