Purification and Antioxidant Activity of Aloe Vera Leaf Lectin (original) (raw)
Related papers
Separation and some properties of Aloe vera L. leaf pulp lectins
Phytotherapy Research, 1999
The separation and partial purification of two lectins from the leaf pulp of Aloe vera L. (=barbadensis Miller) is presented. The fraction showing haemagglutinating activity was precipitated at 50% ammonium sulphate concentration from the crude leaf pulp extract. The precipitate thus obtained, after dialysis, was applied to a hydroxylapatite column. Stepwise elution resulted in two peaks showing haemagglutinating activity eluted with 5 mM (Aloctin I) and 20 mM (Aloctin II) phosphate buffers. Haemagglutinating activity was estimated visually by adding a 4% rabbit erythrocyte suspension to serial two-fold dilutions of the lectins in microtitration plates. None of the 20 sugars tested inhibited haemagglutinating activity of Aloctin I up a concentration of 500 mM. Aloctin II was inhibited by N-acetyl-Dgalactosamine at 250 mM concentration. Of 10 metal ions tested, only Al 3 salts were found to activate Aloctin I and II. On the other hand, it was shown that neither lectin possessed any aand bgalactosidase or aand bglucosidase activity. The lectins were of glycoprotein structure containing approximately 5% neutral sugar. The specificity of the lectins towards human and rat erythrocytes was investigated.
In-vitro studies on lectin derivatives of Aloe excelsa (Berger)
Journal of Medicinal Plants Research, 2010
Current traditional remedies for cure in various ailments including skin treatments have been on the increase. Aloe excelsa has been noted to be used extensively by indigenous people for sun burns, burns, sores as well as a systemic remedy. The agglutination activity by A. excelsa has been credited to the presence of lectins or lectin like derivatives. Aloctin A from A. excelsa was tested against rat, rabbit and human serum, a positive reaction with human α-2-macroglobulin was observed. Furthermore, activities as an anti-tumor agent as well as wound healing properties have been validated. Key words: Aloe excelsa, lecitins, agglutination, traditional use.
Asian Pacific Journal of Cancer Prevention
The multiple biological effects of the "wonder plant" Aloe vera (L.) Burm. f. (Xanthorraceae, formerly Aloaceae and Liliaceae) were proved and reviewed by scientific research (Akev et al., 2015). Several in vivo studies were conducted from 1980's to date with A. vera leaf extracts regarding their antitumour effects (Winters et al., 1981; Gribel and Pashinskiĭ, 1986; Akev et al., 2007a). Aloe emodin (AE) is an anthraquinone glycoside purified from A. vera. In addition to its well established laxative effect, AE have been reported to exhibit antiviral, antimicrobial, hepatoprotective and anticancer properties. Considerable attention has been given recently to the possibility of utilizing AE as a chemotherapeutic drug for the treatment of various types of cancers (Yordanova and Koprinarova, 2014). Lectins are proteins or glycoproteins that bind to specific sugar residues on cell surfaces (Sharon and Lis, 1972). Lectins play multiple roles in inter-and intra-cellular
Therapeutic properties of lectins in herbal supplements
Phytochemistry Reviews, 2018
Medicinal plants host numerous therapeutic low molecular weight phytochemicals and macromolecules such as polysaccharides and proteins. Lectins are glycan binding proteins ubiquitous in the cell and the extracellular surface of all living organisms. Plant parts contain lectins with diverse glycan binding specificities. This review highlights the occurrence of lectins in herbal remedies, their persistence, and bioactivity. Lectins' roles in plants include signaling, defense, and stress responses. The species, plant part, biotic and abiotic factors influence the type and concentration of lectins. Many lectins withstand herbal portions preparation procedures, resist degradation in the alimentary canal and crossover to the circulatory system. Exogenous plant lectins bind glycans with high specificity eliciting cellular responses that include antimicrobial, antitumor and immunomodulation effects. Some lectins are deleterious to normal physiology.
Purification and properties of a mitogenic lectin from Lathyrus sativus seeds
Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1982
A mitogenic lectin has been isolated from saline extract of Lathyrus sativus by (NH4)2SO 4 precipitation, chromatography on DEAE-Sepharose and subsequent affinity chromatography on Sephadex G-100. The lectin has a molecular weight of 49000, as determined by ultracentrifugation, and consists of heavy (M r 19000) and light subunits (M r about 4400). The amino acid composition and N-terminal sequence of both subunits are given. The lectin agglutinated human erythrocytes of different ABO groups equally well, and the agglutination is inhibited best by D-mannose and D-glucose and their a-methyi-glucosides. High concentrations of the iectin were needed for optimal stimulation of human lymphocytes.
Research update: Lectin enriched fractions of herb and dry extract of Urtica dioica L
Urtica dioica L is a plant rich in flavonoids, carotenoids, caffeoylmalic acid and has an established medical value. Although content of mineral and organic substances of U. dioica L. herb is well characterized, presence of bioactive polypeptides is much less appreciated. Seeds and roots of nettle, have been established as a common source for isolation of lectins. Therefore data on the presence of lectins in herb of nettle is ambiguous. Lectin-enriched protein fractions were isolated from herb (freshand dry) and dry extract of U. dioica L. by using homogenisation with fluid nitrogen, extraction in 0.01 M phosphate-buffer saline (PBS), concentrating, salting and precipitation. The amount of protein was measured using photometric Bradford method. A proteomic analysis using 2D gel electrophoresis was performed for lectin – enriched protein fractions isolation and analysis. We estimated quantity of protein and lectins, assessed their blood cell agglutinating activity using tests employi...
Pharmacognosy Journal
Objective: Lectins are extremely significant biomolecules to study several biological progressions. In this present investigation, we are screening the crude phloem exudate/ sap sample from different ethnomedicinal plants were evaluated for lectin and anticancer activity. Methods: The lectin activity of crude phloem exudate/sap samples were confirmed by haemgglutination assay and anticancer activity by using trypan blue, MTT and in-ovo CAM angiogenic assay. The tumor cell nuclei resulting in Giemsa stain, AO/EtBr stain, DNA Fragmentation and Caspase-3 inhibitor assay. Results: Our experimental data show that the phloem exudate/sap sample S2 (Musa acuminata), sample S4 (Euphorbia geniculate) exerting the potent lectin activity, sample S5 exerting very low lectin activity against the trypsinized rabbit erythrocytes and decreases the cell viability in EAC cells in-vitro. Sample S2, S4 and S5 exerts significant cytotoxic effect against the various human cancer cell lines and regressed the neovasculature (development of new blood vessels) in the developing CAM embryos when compared to the other crude samples. The apoptotic inducing activity of crude phloem exudate/sap samples was revealed by DNA fragmentation assay, caspase-3 inhibitor assay and cellular morphology were studied by fluorescence staining methods. Conclusion: This study reports that some of the isolated crude phloem exudate/sap samples show potent lectin activity and anti-cancer activity in different human cancer cell lines. The further additional experiment needs to purify and characterize the bioactive lectin components from the potent sample which is responsible for pro-apoptotic, anti-angiogenic activity and mechanism involved.
Purification of a lectin from Amaranthus leucocarpus by affinity chromatography
Phytochemistry, 1988
A lectin of M, ca 45,000 per subunit from Amaranthus leucocarpus seeds, has been isolated and purified by affinity chromatography using a stroma column. It is a glycoprotein (10% w/w carbohydrate) containing six N-acetyl-D-glucosamines, four D-galactoses, one D-glucose and traces of xylose residues for each three D-mannose residues per molecule. Its amino acid composition reveals a predominance of acidic residues (aspartic and glutamic) and of glycine and alanine. In addition, the lectin contains an unusual amount of essential aminoacids such as methionine, tryptophan and lysine. Electrophoretically and chromatographically homogenous, it focuses as a multiple-band protein in the pH range of 4.8-5.2. It agglutinates the different human blood groups of the ABO system equally well, albeit being inhibited by N-acetyl-D-galactosamine in a specific fashion. In contrast to A. caudatus hemagglutinin A. leucocarpus lectin is inhibited by serum glycoproteins such as fetuin, it is mitogenic and is not toxic.
IRJET- A Review on cDNA Isolation and Anti-Mitogenic Properties of Plant Leaf Lectins
IRJET, 2021
This review describes the anti-mitogenic properties of lectins isolated from specific plants. Lectins square measure the proteins found in the majority food particularly grains and legumes and cosmopolitan in animals and microbes too. Lectins principally bind to carbohydrates whereas their specific property is to cause precipitation of molecules that contain carbohydrates. Lectins square measure versatile proteins of non-immune origin and their multi variant structure presents nice therapeutic and biotechnological potential. Bound lectins conjointly agglutinate erythrocytes thanks to their capability to bind with the cells surface glycolipids and glycoproteins.
Plant Lectins: Biochemical Characterization and Function
2013
The present paper is dedicated to plant lectins, their classifi cation, molecular structure, distribution in different plant organs and involvement in such biological functions as: cell to cell communication, phytoimmunity, symbiotic relationships, also cytotoxic action, mitogenic activity and participation in the immune reactions (system of complement). The future use of lectins in medical practice has been considered.