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Purification, Biochemical Characterization, and Bioactive Properties of a Lectin Purified from the Seeds of White Tepary Bean (Phaseolus Acutifolius Variety Latifolius)  [PDF]
Carmen Valadez-Vega,Ana María Guzmán-Partida,Francisco Javier Soto-Cordova,Gerardo álvarez-Manilla,José A. Morales-González,Eduardo Madrigal-Santillán,José Roberto Villagómez-Ibarra,Clara Zú?iga-Pérez,José Gutiérrez-Salinas,Marco A. Becerril-Flores
Molecules , 2011, DOI: 10.3390/molecules16032561
Abstract: The present work shows the characterization of Phaseolus acutifolius variety latifolius, on which little research has been published, and provides detailed information on the corresponding lectin. This protein was purified from a semi-domesticated line of white tepary beans from Sonora, Mexico, by precipitation of the aqueous extract with ammonium sulfate, followed by affinity chromatography on an immobilized fetuin matrix. MALDI TOF analysis of Phaseolus acutifolius agglutinin (PAA) showed that this lectin is composed of monomers with molecular weights ranging between 28 and 31 kDa. At high salt concentrations, PAA forms a dimer of 63 kDa, but at low salt concentrations, the subunits form a tetramer. Analysis of PAA on 2D-PAGE showed that there are mainly three types of subunits with isoelectric points of 4.2, 4.4, and 4.5. The partial sequence obtained by LC/MS/MS of tryptic fragments from the PAA subunits showed 90–100% identity with subunits from genus Phaseolus lectins in previous reports. The tepary bean lectin showed lower hemagglutination activity than Phaseolus vulgaris hemagglutinin (PHA-E) toward trypsinized human A and O type erythrocytes. The hemagglutination activity was inhibited by N-glycans from glycoproteins. Affinity chromatography with the immobilized PAA showed a high affinity to glycopeptides from thyroglobulin, which also has N-glycans with a high content of N-acetylglucosamine. PAA showed less mitogenic activity toward human lymphocytes than PHA-L and Con A. The cytotoxicity of PAA was determined by employing three clones of the 3T3 cell line, demonstrating variability among the clones as follows: T4 (DI50 51.5 μg/mL); J20 (DI50 275 μg/mL), and N5 (DI50 72.5 μg/mL).
Badri Tavasolian,S Mottaghian
Iranian Journal of Public Health , 1979,
Abstract: Iranian castor bean lectin was isolated and purified by several column chromatography methods. Then, the sugar and amino acid content of the purified lectin was identified. Castor bean lectin has some anti tumor and anti leukemia action. Thus it may be used commercially for medical and biochemical purposes.
Immunomodulatory activities of five clinically used Chinese herbal polysaccharides
Xiaojuan He,Xuyan Niu,Jian Li,Shaohua Xu
Journal of Experimental and Integrative Medicine , 2012,
Abstract: Polysaccharide is a natural macromolecular compound with complex, important and multifaceted biological activities. Some of polysaccharides have been marketed in China as drugs or healthy products. More studies confirm that the active ingredient of many traditional Chinese medicine exist in the form of polysaccharides. They play a role in disease therapy by activating immune cells and the complement system; regulating the cytokines expression; promoting the production of antibodies; inhibiting tumor cell proliferation and inducing tumor cell apoptosis; inhibiting virus entering cells and replication; increasing activity of antioxidant enzyme; scavenging free radicals; and inhibiting lipid peroxidation. In this review, we focus on the immunomodulatory effects and its possible mechanism of polysaccharides from Chinese herbal polysaccharides products, including Lentinan, Astragalus polysaccharide, Polyporus polysaccharide and Achyranthes bidentata polysaccharide. The immunomodulatory activities of polysaccharides were categorized in the paper into general immunoregulatory activity, anti-tumor, anti-infections, anti-inflammatory, anti-oxidative, anti-mutagenic and radioprotective, anti-complementary, anti-adhesive, and anti-allergy since all the activities are related to modulate immune responses by the polysaccharides. Also the challenges in the research of polysaccharides will be discussed. [J Exp Integr Med 2012; 2(1.000): 15-27]
Purification and characterisation of a lectin from the red marine alga Pterocladiella capillacea (S.G. Gmel.) Santel. & Hommers.
Brazilian Journal of Botany , 2002,
Abstract: A lectin present in the marine red alga Pterocladiella capillacea was purified and characterised by extraction of soluble proteins (crude extract) in 20 mM Tris-HCl buffer, pH 7.5. Among the analysed erythrocytes (human blood group A, B and O and the animals ox, goat, chicken and rabbit) the lectin agglutinated specifically rabbit erythrocytes. The hemagglutinating activity assay showed that the lectin was not dependent on divalent cations and was shown to be inhibited by the glycoproteins avidin and mucin. The purification procedure was conduced by precipitation of the crude extract with 80% saturation ammonium sulfate (F0/80) followed by affinity chromatography on guar-gum column. The lectin of P. capillacea was purified 14.5 fold and had a recovery of 27.4% of the original total specific activity present in the crude extract. The absence of carbohydrate suggested that the lectin is not a glycoprotein. The molecular mass of P. capillacea lectin, determined by gel filtration, was 5.8 kDa. SDS-PAGE in the presence of -mercaptoethanol gave one band, indicating that the native lectin is a monomeric protein. The activation energy of denaturation process (D G') was calculated to be 106.87 kJ . mol-1 at 70 masculineC.
Interaction of Glucose/Sucrose Binding Lectin Isolated from Nigeria Wild Bean with E. coli and S. aureus  [PDF]
O. A. Awoyinka, J. O. Awe, O. A. Omosebi, O. Osukoya, F. C. Oladele, B. A. Olofinbiyi, M. F. Asaolu
Food and Nutrition Sciences (FNS) , 2017, DOI: 10.4236/fns.2017.812080
Lectin purified from wild underutilized local bean—Otili, Feregede, Pakalai was comparatively characterized and further evaluated for interaction with gastrointestinal bacteria—Esherichia coli and Staphylococcus aureus. The purified lectin in all the bean samples showed to be glucose and sucrose binding. The hemagglutinating activity, was non selective to type of blood group (A, B, AB and O). Anti-bacteria interaction with Escherichia coli showed clear zone of inhibition of about 1.5 ± 0.5 mm with lectin from Feregede and Otili while there was slight agglutination with lectin from Pakala. Staphylococcus aureus sensitivity to the lectin extracted from Otili with clear zone of inhibition of 2.0 ± 0.5 mm was also found in the control chloramphenicol. However there was pronounced agglutination with lectin from Feregede and Pakala with Staphylococcus auereus. This may be a clear indication that lectin from local underutilized wild bean understudy will agglutinate and interact with a gram positive bacteria more than gram negative bacteria.
Purification and partial characterisation of a lectin from the red marine alga Vidalia obtusiloba C. Agardh
Melo, Fábio R.;Benevides, Norma M.B.;Pereira, Maria G.;Holanda, Márjory L.;Mendes, Francisca N.P.;Oliveira, Stélio R.M.;Freitas, Ana L.P.;Silva, Luana M.C.M.;
Brazilian Journal of Botany , 2004, DOI: 10.1590/S0100-84042004000200006
Abstract: the lectin of the red marine alga vidalia obtusiloba was purified by a combination of ammonium sulphate precipitation, ion-exchange chromatography on deae-cellulose and affinity chromatography on cross-linked guar gum. the lectin preferentially agglutinated native and bromelain-treated human group o erythrocytes. the haemagglutinating activity revealed that the lectin was dependent on divalent cations (ca++ or mn++) and was shown to be inhibited by n-acetyl-galactosamine, d-galactosamine, a-lactose and d-galactose and by the glycoprotein porcine stomach mucin. the molecular mass of the lectin, estimated by gel filtration, was 78.9 kda while by sds-page, in the presence of b-mercaptoethanol, the lectin exhibited two different protein subunits with mr of 59.6 and 15.2 kda, suggesting that the lectin is a dimeric protein. isoelectric focusing revealed the presence of a simple acidic protein with an isoelectric point between 4 and 5. the purified lectin showed a carbohydrate content of 43.2% and a predominance of the amino acids asp/asn, glu/gln and leu. the energy of activation (dg') for the denaturation of the lectin was estimated to be 25.4 kcal.mol-1 at 90 oc. immunochemical assays using a rabbit antiserum raised against the purified lectin of v. obtusiloba showed that it was possible to detect the presence of the lectin at different steps of the purification process. western blotting of sds-page gels showed immunostaining of only the larger of the lectin subunits.
Isolation, Partial Purification and Characterization of Texas Live Oak (Quercus fusiformis) Lectin  [PDF]
Ruby A. Ynalvez, Carmen G. Cruz, Marcus A. Ynalvez
Advances in Bioscience and Biotechnology (ABB) , 2015, DOI: 10.4236/abb.2015.67049
Abstract: Lectins are carbohydrate-binding proteins with agglutination properties. There is a continuous interest in lectins due to their biological properties that can be exploited for medicinal and therapeutic purposes. The objective of this study was to isolate and characterize lectin activity in Texas Live Oak (Quercus fusiformis). More specifically, the study aimed to determine the lectin’s blood group specificity and pH stability, determine effects of seasonal variation, soil moisture and soil pH on lectin activity. The study also aimed to determine the presence of antifungal activity in Q. fusiformis extracts. Lectin activity was detected and compared via agglutination and protein assays. Protein partial purification was accomplished using diethylaminoethyl ion-exchange chromatography matrix. High Performance Liquid Chromatography (HPLC) was used to assess purity of the lectin. Results showed that Q. fusiformis extracts’ lectin activities are stable at a pH range of 5.2 - 9.2 but with a significant decrease in activity above pH 9.2. The lectin activity was significantly higher when assayed against sheep red blood cells as compared to other blood groups tested. Quercus fusiformis extract is devoid of antifungal activity against Aspergillus niger and Rhizopus stolonifer. The effects of seasonal variation, soil moisture and soil pH do not significantly correlate with lectin activity. Results from HPLC showed presence of three peaks indicating a partial purification of the Q. fusiformis lectin.
Purification and Characterization of a Lectin from Phaseolus vulgaris cv. (Anasazi Beans)
Arishya Sharma,Tzi Bun Ng,Jack Ho Wong,Peng Lin
Journal of Biomedicine and Biotechnology , 2009, DOI: 10.1155/2009/929568
Abstract: A lectin has been isolated from seeds of the Phaseolus vulgaris cv. “Anasazi beans” using a procedure that involved affinity chromatography on Affi-gel blue gel, fast protein liquid chromatography (FPLC)-ion exchange chromatography on Mono S, and FPLC-gel filtration on Superdex 200. The lectin was comprised of two 30-kDa subunits with substantial N-terminal sequence similarity to other Phaseolus lectins. The hemagglutinating activity of the lectin was stable within the pH range of 1–14 and the temperature range of 0–80°C. The lectin potently suppressed proliferation of MCF-7 (breast cancer) cells with an IC50 of 1.3 M, and inhibited the activity of HIV-1 reverse transcriptase with an IC50 of 7.6 M. The lectin evoked a mitogenic response from murine splenocytes as evidenced by an increase in [3H-methyl]-thymidine incorporation. The lectin had no antifungal activity. It did not stimulate nitric oxide production by murine peritoneal macrophages. Chemical modification results indicated that tryptophan was crucial for the hemagglutinating activity of the lectin.
Isolation of a Glucosamine Binding Leguminous Lectin with Mitogenic Activity towards Splenocytes and Anti-Proliferative Activity towards Tumor Cells  [PDF]
Yau Sang Chan, Jack Ho Wong, Evandro Fei Fang, Wenliang Pan, Tzi Bun Ng
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0038961
Abstract: A dimeric 64-kDa glucosamine-specific lectin was purified from seeds of Phaseolus vulgaris cv. “brown kidney bean.” The simple 2-step purification protocol involved affinity chromatography on Affi-gel blue gel and gel filtration by FPLC on Superdex 75. The lectin was absorbed on Affi-gel blue gel and desorbed using 1M NaCl in the starting buffer. Gel filtration on Superdex 75 yielded a major absorbance peak that gave a single 32-kDa band in SDS-PAGE. Hemagglutinating activity was completely preserved when the ambient temperature was in the range of 20°C–60°C. However, drastic reduction of the activity occurred at temperatures above 65°C. Full hemagglutinating activity of the lectin was observed at an ambient pH of 3 to 12. About 50% activity remained at pH 0–2, and only residual activity was observed at pH 13–14. Hemagglutinating activity of the lectin was inhibited by glucosamine. The brown kidney bean lectin elicited maximum mitogenic activity toward murine splenocytes at 2.5 μM. The mitogenic activity was nearly completely eliminated in the presence of 250 mM glucosamine. The lectin also increased mRNA expression of the cytokines IL-2, TNF-α and IFN-γ. The lectin exhibited antiproliferative activity toward human breast cancer (MCF7) cells, hepatoma (HepG2) cells and nasopharyngeal carcinoma (CNE1 and CNE2) cells with IC50 of 5.12 μM, 32.85 μM, 3.12 μM and 40.12 μM respectively after treatment for 24 hours. Flow cytometry with Annexin V and propidum iodide staining indicated apoptosis of MCF7 cells. Hoechst 33342 staining also indicated formation of apoptotic bodies in MCF7 cells after exposure to brown kidney bean lectin. Western blotting revealed that the lectin-induced apoptosis involved ER stress and unfolded protein response.
Purification and Characterization of a Lectin from the Seeds of Psophocarpus palustris  [PDF]
Kuku Adenike,Agboola Femi Kayode,Aboderin Akintola
Pakistan Journal of Biological Sciences , 2005,
Abstract: A heamagglutinating protein from the phosphate buffered saline (PBS) extract of the seeds of Psophocarpus palustris was purified by gel filtration on Sephadex G-150 column. The purified lectin agglutinated specifically red blood cells of human type A and neither type B nor type O. This heamagglutinating activity was inhibited by D-mannose and D-galactose. The purified protein showed one band in non-denaturing polyacrylamide gel electrophoresis (PAGE) as well as in SDS-PAGE. This revealed that the lectin is a homogeneous preparation and a dimeric protein with a molecular weight estimated from gel filtration of 45,000 daltons and subunit molecular weight of 22,700 daltons. Treatment of the lectin with 50 mM EDTA or EGTA had no influence on the hemagglutinating activity but Mg2+, Mn2+ and Ba2+ were effective activators of the purified lectin. The optimal pH for heamagglutination was 7. The purified lectin was stable in pH 7-9 but labile at temperatures over 50°C.
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