Erythrina Corallodendron Research Articles

Insights into the Role of Erythrina corallodendron L. in Alzheimer's Disease: in Vitro and in Silico Approach.

Alzheimer's disease (AD) is a major health problem. Cholinergic transmission is greatly affected in AD. Phytochemical investigation of the alkaloid rich fraction (AF) of Erythrina corallodendron L leaves resulted in isolation of five known alkaloids: erysodine, erythrinine, 8-oxoerythrinine, erysovine N-oxide and erythrinine N-oxide. In this study, eysovine N-oxide was reported for the second time in nature. AF was assayed for cholinesterase inhibition at the concentration of 100 μg mL-1 . AF showed a higher percent inhibition for butyrylcholinesterase enzyme (BuChE) (83.28 %) compared to acetylcholinesterase enzyme (AChE) (64.64 %). The isolated alkaloids were also assayed for their anti-BuChE effect. In-silico docking study was done for the isolated compounds at the binding sites of AChE and BuChE to determine their binding pattern and interactions, also molecular dynamics were estimated for the compound displaying the best fit for AChE and BuChE. In addition, ADME parameters and toxicity were predicted for the isolated alkaloids compared to donepezil.

Antimicrobial activities and phylogenetic study of Erythrina senegalensis DC (Fabaceae) seed lectin.

Erythrina senegalensis (Fabaceae) have been traditionally used in the treatment of microbial ailments, and the specific agent mediating its efficacy has been investigated in several studies. In this study, the antimicrobial activity of purified E. senegalensis lectin (ESL) was analyzed. The phylogenetic relationship of the gene encoding lectin with other legume lectins was also established to investigate their evolutionary relationship via comparative genomics. Antimicrobial activity of ESL against selected pathogenic bacteria and fungi isolates was evaluated by the agar well diffusion method, using fluconazole (1 mg/ml) and streptomycin (1 mg/ml) as positive controls for fungi and bacteria sensitivity, respectively. Potent antimicrobial activity of ESL against Erwinia carotovora, Pseudomonas aeruginosa, Klebsiella pneumonia, Staphylococcus aureus, Aspergillus niger, Penicillium camemberti, and Scopulariopsis brevicaulis was observed, with inhibition zones ranging from 18 to 24 mm. Minimum inhibitory concentrations of ESL ranged between 50 and 400 μg/ml. Primer-directed polymerase chain reaction of E. senegalensis genomic DNA detected a 465-bp lectin gene with an open reading frame encoding a 134-amino acid polypeptide. The obtained nucleotide sequence of the ESL gene shared high sequence homology: 100, 100, and 98.18% with Erythrina crista-galli, Erythrina corallodendron, and Erythrina variegata lectin genes, respectively, suggesting that the divergence of Erythrina lectins might follow species evolution. This study concluded that ESL could be used to develop lectin-based antimicrobials, which could find applications in the agricultural and health sectors.

Five new Erythrina alkaloids from the stems of Erythrina corallodendron

Five new Erythrina alkaloids and five known E. alkaloids were isolated from a 95% ethanol extract of the stems of Erythrina corallodendron L. Their chemical structures were elucidated by UV, IR, HRESIMS, NMR and X-ray. Furthermore, the analgesic activities of E. alkaloids 1, 2 and 6 were evaluated by using an acetic acid-induced writhing test in mice, and their writhing inhibition rates were 67.9%, 64.6% and 70.3% at doses of 20 mg/kg, respectively.

Three new erythrina alkaloids from the roots of Erythrina corallodendron

Three new erythrina alkaloids, eryalkals A (1), B (2), and C (3), were isolated from the roots of Erythrina corallodendron L. Their structures, including their absolute configurations, were elucidated based on analyses of HR-ESI-MS, 1D/2D NMR and single-crystal X-ray diffraction techniques. The isolated erythrina alkaloids were screened for the antioxidant and cytotoxic activities. All the compounds showed no antioxidant activity and cytotoxic activities.

Erythrina alkaloids from stems of Erythrina corallodendron

This study aims to investigate Erythrina alkaloids from the stems of Erythrina corallodendron. Eighteen Erythrina alkaloids were isolated from the 95% ethanol extract of the stems of E. corallodendron by silica gel,octadecyl silica( ODS),Sephadex LH-20 column chromatography and preparative HPLC. With nuclear magnetic resonance( NMR) spectroscopy and mass spectrometry( MS),their structures were identified as crstanine A( 1),erytharbine( 2),cristamine C( 3),( +)-erystramindine( 4),10,11-dioxoerythraline( 5),8-oxoerythraline( 6),8-oxo-11β-methoxyerythradine( 7),11-methoxyerythradine( 8),( ±)-11-epi-methoxyerythraline( 9),( +)-erythraline( 10),crystamidine( 11),8-oxoerythrinine( 12),( +)-11α-hydroxyerysotrine( 13),erythrinine( 14),erysodine( 15),erysotrine-N-oxide( 16),( +)-erythratidine( 17),erythratine( 18). Compounds 1-4,7,9,11,13,16 and 17 were isolated from E. corallodendron for the first time. Furthermore,the cytotoxic activities of these Erythrina alkaloids were screened by MTT assay. The results showed that all compounds had no obvious cytotoxic activity. The analgesic activities of compounds1,6 and 8 were evaluated using an acetic acid-induced writhing test in mice. The writhing inhibition rates of compounds 1,6 and 8 at20 mg·kg~(-1)( ip) were 69%,70% and 62%,respectively( P<0. 01),indicating they have significant analgesic activity.

New Selective Human MAO-B Inhibitors from the Stems of Erythrina corallodendron L.

One new, 10, 11-dioxo-6,7α-erythraline epoxide (A1) and four known erythrinan alkaloids 10, 11-dioxo-erythraline (A2), erysodine (A3), 8-oxo-erythraline (A4) and erythraline (A5) were isolated from the 70% methanolic extract of stems of E. Corallodendron (Fabaceae). The isolated compounds were elucidated by exploiting 1D/2D NMR, and HR-ESI-MS analysis. The absolute configuration of A1 was determined by electronic circular dichroism (ECD). Mono Amine Oxidase inhibitory activity of the isolated alkaloids was investigated in vitro using kynuramine deamination assay on recombinant human MAO-A and B enzymes. The binding modes were predicted by molecular docking and the structure activity relationships of erythrinans were then evaluated. All isolated alkaloids demonstrated preferential activity against MAO-B. A1 displayed the highest potency and selectivity against MAO-B with IC50 of 25.18 μM, (SI >3.97). The selective inhibition exhibited by erythrinan alkaloids against MAO-B is in line with the expected biological impact of Erythrina in the treatment of neurodegenerative diseases and presents this chemical class as promising leads for managing AD and PD diseases.

Essential oil extracted from erythrina corallodendron L. leaves inhibits the proliferation, migration, and invasion of breast cancer cells.

Erythrina corallodendron L., a kind of landscape tree, has long been used as a traditional medicine. In this study, the composition of essential oil extracted from the leaves was analysed by GC-MS (gas chromatograph-mass spectrometer), with linalool identified as the main compound. Its cytotoxicity against MDA-MB-231, MCF-7 and HMLE cells was examined by MTT and cloning assays. Transwell and wound-healing assays were used to examine the inhibition of migration and invasion. Western blot, qRT-PCR and immunofluorescence staining were used to measure the mRNA and protein expression of factors related to EMT (snail, slug, E-cadherin, N-cadherin and vimentin). The essential oil of Erythrina corallodendron leaves was found to inhibit the proliferation, migration and invasion of breast cancer cells in a dose-dependent manner. The findings of this study suggest that the essential oil of E. corallodendron leaves may merit further investigation as a potential clinical or adjuvant drug for treating breast cancer migration and invasion.

Chemical compositions from roots of Erythrina corallodendron

This project is to investigate chemical compositions from the roots of Erythrina corallodendron. Through the methods of silica gel,ODS,Sephadex LH-20 column chromatography and preparative HPLC,15 compounds were isolated from the 95% ethanol extract of the roots of E. corallodendron. Based on spectroscopic techniques,the structures of these compounds were identified as 10,11-dioxoerythraline( 1),erythrinine( 2),erythraline( 3),11-methoxyerythraline( 4),cristanines B( 5),erythratine( 6),erysotrine( 7),medioresinol( 8),( ±)-ficusesquilignan A( 9),( +)-pinoresinol( 10),nicotinic acid( 11),dibutyl phthalate( 12),vanillic acid( 13),3-hydroxy-1-( 4-hydroxy-3-methoxyphenyl)-1-propanone( 14),and syringic acid( 15). Compounds 8-10 are isolated from genus Erythrina for the first time and all compounds are isolated from E. corallodendron for the first time. Furthermore,this paper screened the antioxidant and cytotoxic activities of the compounds using models of liver microsomal oxidation inhibition and MTT.

A Novel Compound and Biological Evaluation of Phytoconstituents Isolated from Erythrina corallodendron L. Flowers

Objective: This study aimed at phytochemical investigation of the 70% alcoholic extract of Erythrina corallodendron L. flowers and biological evaluation of the isolated compounds for their activity as antiprotozoal drugs also evaluation the binding affinity to opioid and cannabinoid receptors as well as the inhibition activity against monoamine oxidase (MAO) enzymes. Method: The 70% alcoholic extract was subjected to successive column chromatographic (CC) separations using silica gel normal phase, reversed phase RP-18, Diaion HP-20, and Sephadex LH-20. The structural elucidation of the isolated compounds was achieved using HR-ESI-MS, UV, 1D and 2D NMR spectroscopic analysis. The isolated compounds were screened in vitro for the binding affinity to opioid and cannabinoid receptors using receptor binding assay as well as the inhibition activity against MAO enzymes using kynuramine deamination assay, while their antiprotozoal activity was evaluatedusing parasitelactate dehydrogenase serum assay (pLDH). Results: The phytochemical evaluation of the alcoholic extract of E.corallodendron flowers, afforded the isolation of an indole alkaloid Hypaphorine 1, a new flavonoid glucoside; Kaempferol-3-O-α-sophoroside 2 and three known flavonoid C-glycosides vis;, Neoschaftoside 3, Isoschaftoside 4 and Vicenin-II 5. Compounds 3 and 4 are reported for the first time from genus Erythrina. Compounds 4 and 5 showed significant antimalarial activity both with IC50 value 1.7µg/mL against (D6) strain and with IC50 1.4 and 1.1 µg/mL against (W2) strain, respectively. Compound 3 showed selective inhibition to MAO-B with IC50 value of 32.08 µM and selective index (SI) > 3.12. Conclusion: The significant antiplasmodial activity of compounds 4 and 5 correlated the known antimalarial activity of different Erythrina species to flavonoid C-glycosides, Also compounds 3 and 4 are position isomers but exhibited different response against MAO-B which gives indication about the selectivity pattern of the flavonoid C-glycosides with MAO-B receptor subtype.

Alkaloids from flowers of Erythrina corallodendron

Two new Erythrina alkaloids, 10-oxo-erythrinine (1) erythrinine N-oxide (2) together with 23 known ones were obtained from the flowers of Erythrina corallodendron. The structures were determined based on analysis of their spectroscopic data. All compounds were first isolated from plants of Erythrina corallodendron.

Potential pesticides for control of a recently introduced ambrosia beetle (Euwallacea sp.) in southern California

Polyphagous shot hole borer (PSHB) has recently invaded southern California. This beetle attacks more than 200 host tree species, including avocado (Persea americana Mill.) and many important native, urban landscape and nursery stock trees including sycamore (Platanus racemosa Nutt.), and box elder (Acer negundo L.). The beetle, along with its associated fungi, causes branch dieback and tree mortality in a large variety of tree species. Due to the severity of the impact of PSHB, short-term management tools must include chemical control options for the industry and private landowners to protect trees. We assessed the effectiveness of systemic and contact insecticides for control of PSHB in laboratory tests using fresh-cut castor bean (Ricinus communis L.) branches. Castor bean was chosen because, as a weedy species, it is widely available, and it is a preferred host for the beetles. We conducted field tests using mature, weedy, infested field-grown castor bean. We also surveyed infested coral trees (Erythrina corallodendron L.) in an established residential landscape. For field-grown infested castor bean, beetle activity was lowest for plants treated with bifenthrin, imidacloprid and dinotefuran. Bifenthrin was the most effective insecticide for reducing beetle attacks and gallery formation in castor bean branches in laboratory experiments with cut branches. Dinotefuran was more variable in effectiveness in laboratory trials. Fenpropathrin, clothianidin and orange oil extracts did not differ from untreated controls in beetle attacks and gallery formation. Based on these results, bifenthrin and imidacloprid were selected for further testing in combination with fungicides for control of PSHB.

Phytochemical Investigation Of Erythrina Corallodendron. (Fabaceae)

The phytochemical analysis of the 70% methanol extract of both the flowers and the stems of Erythrina Corallodendron L. (Fabaceae) cultivated in Egypt resulted in isolation and identification of seven flavonoids: two isoflavonoids: daizdizen (1), genistein (2), three C-glycosides: vicenin-2 (3), schaftoside (4), isoscaftoside (5), one O-glycoside: Kaempferol 3-O- β-D-sophoroside (6), one petrocarpan: (6aR,11aR)-3,9-dihydroxypetrocarpan (7) and five alkaloids: one indole alkaloid: hypaphorine (8), four erythrinan alkaloids: erysodine (9), erythbidin β (10), 8-oxoerythraline (11) and 10,11-dioxoerythraline (12). Compounds 1, 2, 4, 5, 6, 7, 10, 11, and 12 are reported for the first time from this species. The structures of the isolated compounds were elucidated using UV, 1D and 2D NMR and HRESIMS techniques.

α-N-Linked glycopeptides: conformational analysis and bioactivity as lectin ligands

Natural N-glycosylation involves a β-anomeric linkage connecting the sugar to one asparagine residue of the protein. We herein report NMR- and modelling-based data on glycomimetics containing α-glycosidic linkages. The bioactivity of α-Gal-containing glycopeptides has been documented by revealing binding to two plant lectins, i.e. a potent β-trefoil toxin (Viscum album agglutinin) and β-sandwich lectin (Erythrina corallodendron agglutinin), by NMR protocols. Docking provided insights into the 3D structures of the resulting complexes. These results provide the basis to introduce α-substituted neoglycopeptides to the toolbox of scaffold for the design of potent lectin inhibitors.

Guard cells on adaxial and abaxial epidermes of Erythrina corallodendron sepals

This study investigated guard cells on the adaxial and the abaxial epidermes during Erythrina corallodendron sepal development. On the adaxial epidermis, the morphology of guard cells was highly variable and changes in aperture induced by abscisic acid (ABA) were observed in 9.1 % stomata, while on the abaxial epidermis 86.7 % stomata responded to ABA. On the adaxial epidermis, stomata did not close even when guard cell pressure potential was reduced to zero by plasmolysis, even if fluorescein diacetate revealed that guard cells were alive. It was concluded that guard cells on the adaxial and the abaxial epidermes of sepals sensed environmental conditions differently, maybe due to different guard cell wall elasticity.

Guard cells on adaxial and abaxial epidermes of Erythrina corallodendron sepals

This study investigated guard cells on the adaxial and the abaxial epidermes during Erythrina corallodendron sepal development. On the adaxial epidermis, the morphology of guard cells was highly variable and changes in aperture induced by abscisic acid (ABA) were observed in 9.1 % stomata, while on the abaxial epidermis 86.7 % stomata responded to ABA. On the adaxial epidermis, stomata did not close even when guard cell pressure potential was reduced to zero by plasmolysis, even if fluorescein diacetate revealed that guard cells were alive. It was concluded that guard cells on the adaxial and the abaxial epidermes of sepals sensed environmental conditions differently, maybe due to different guard cell wall elasticity.

Role of glycosylation in structure and stability of Erythrina corallodendron lectin (EcorL): A molecular dynamics study

The effect of glycosylation on structure and stability of glycoproteins has been a topic of considerable interest. In this work, we have investigated the solution conformation of the oligosaccharide and its effect on the structure and stability of the glycoprotein by carrying out a series of long Molecular dynamics (MD) simulations on glycosylated Erythrina corallodendron lectin (EcorL) and nonglycosylated recombinant Erythrina corallodendron lectin (rEcorL). Our results indicate that, despite the similarity in overall three dimensional structures, glycosylated EcorL has lesser nonpolar solvent accessible surface area compared to nonglycosylated EcorL. This might explain the experimental observation of higher thermodynamic stability for glycosylated EcorL compared to nonglycosylated EcorL. Analysis of the simulation results indicates that, dynamic view of interactions between protein residues and oligosaccharide is entirely different from the static picture seen in the crystal structure. The oligosaccharide moiety had dynamically stable interactions with Lys 55 and Tyr 53, both of which are separated in sequence from the site of glycosylation, Asn 17. It is possible that glycosylation helps in forming long-range contacts between amino acids, which are separated in sequence and thus provides a folding nucleus. Thus our simulations not only reveal the conformations sampled by the oligosaccharide, but also provide novel insights into possible molecular mechanisms by which glycosylation can help in folding of the glycoprotein by formation of folding nucleus involving specific contacts with the oligosaccharide moiety.

Modification of the sugar specificity of a plant lectin: structural studies on a point mutant ofErythrina corallodendronlectin

A mutant of Erythrina corallodendron lectin was generated with the aim of enhancing its affinity for N-acetylgalactosamine. A tyrosine residue close to the binding site of the lectin was mutated to a glycine in order to facilitate stronger interactions between the acetamido group of the sugar and the lectin which were prevented by the side chain of the tyrosine in the wild-type lectin. The crystal structures of this Y106G mutant lectin in complex with galactose and N-acetylgalactosamine have been determined. A structural rationale has been provided for the differences in the relative binding affinities of the wild-type and mutant lectins towards the two sugars based on the structures. A hydrogen bond between the O6 atom of the sugars and the variable loop of the carbohydrate-binding site of the lectin is lost in the mutant complexes owing to a conformational change in the loop. This loss is compensated by an additional hydrogen bond that is formed between the acetamido group of the sugar and the mutant lectin in the complex with N-acetylgalactosamine, resulting in a higher affinity of the mutant lectin for N-acetylgalactosamine compared with that for galactose, in contrast to the almost equal affinity of the wild-type lectin for the two sugars. The structure of a complex of the mutant with a citrate ion bound at the carbohydrate-binding site that was obtained while attempting to crystallize the complexes with sugars is also presented.

Differential staining of Western blots of human secreted glycoproteins from serum, milk, saliva, and seminal fluid using lectins displaying diverse sugar specifities

Human milk, serum, saliva, and seminal fluid glycoproteins (gps) nourish and protect newborn and adult tissues. Their saccharides, which resemble cell membrane components, may block pathogen adhesion and infection. In the present study, they were examined by a battery of lectins from plants, animals, and bacteria, using hemagglutination inhibition and Western blot analyses. The lectins included galactophilic ones from Aplysia gonad, Erythrina corallodendron, Maclura pomifera (MPL), peanut, and Pseudomonas aeruginosa (PA-IL); fucose-binding lectins from Pseudomonas aeruginosa (PA-IIL), Ralstonia solanacearum (RSL), and Ulex europaeus (UEA-I), and mannose/glucose-binding Con A. The results demonstrated the chosen lectin efficiency for differential analysis of human secreted gps as compared to CBB staining. They unveiled the diversity of these body fluid gp glycans (those of the milk and seminal fluid being highest): the milk gps interacted most strongly with PA-IIL, followed by RSL; the saliva gps with RSL, followed by PA-IIL and MPL; the serum gps with Con A and MPL, followed by PA-IIL and RSL, and the seminal plasma gps with RSL and MPL, followed by UEA-I and PA-IIL. The potential usage of these lectins as probes for scientific, industrial, and medical purposes, and for quality control of the desired gps is clearly indicated.

Effect of glycosylation on the structure of Erythrina corallodendron lectin.

The three-dimensional structure of the recombinant form of Erythrina corallodendron lectin, complexed with lactose, has been elucidated by X-ray crystallography at 2.55 A resolution. Comparison of this non-glycosylated structure with that of the native glycosylated lectin reveals that the tertiary and quaternary structures are identical in the two forms, with local changes observed at one of the glycosylation sites (Asn17). These changes take place in such a way that hydrogen bonds with the neighboring protein molecules in rECorL compensate those made by the glycan with the protein in ECorL. Contrary to an earlier report, this study demonstrates that the glycan attached to the lectin does not influence the oligomeric state of the lectin. Identical interactions between the lectin and the non-covalently bound lactose in the two forms indicate, in line with earlier reports, that glycosylation does not affect the carbohydrate specificity of the lectin. The present study, the first of its kind involving a glycosylated protein with a well-defined glycan and the corresponding deglycosylated form, provides insights into the structural aspects of protein glycosylation.

Probing genetic variation and glycoform distribution in lectins of the Erythrina genus by mass spectrometry

Six leguminous lectins from the seeds of plants of the Erythrina genus, namely E. caffra (ECafL), E. cristagalli (ECL), E. flabelliformis (EFL), E. lysistemon (ELysL), E. rubrinerva (ERL), and E. vespertilio (EVL), were examined to establish their sequence homology and to determine the structure and sites of attachment of their glycans. Tryptic digests of these lectins were analyzed by capillary electrophoresis coupled to electrospray mass spectrometry (CE-ESMS). Assignments were made by comparing the molecular masses of the observed tryptic peptides with those of Erythrina corallodendron lectin (ECorL), the sequence of which had been established previously. Glycan structure and genetic variations in the amino acid sequence were probed by tandem mass spectrometry. Small differences were found between the sequences of the various lectins examined and all of them exhibited C-terminal processing resulting in proteins with a C-terminal Asn residue. The major glycan of these glycoproteins was shown to be the heptasaccharide Man 3XylFucGlcNAc 2, consistent with previous investigations on ECL and ECorL. A minor glycan heterogeneity was observed for most lectins examined except for that of ECafL and ECorL where an extra hexose residue was observed on the reducing GlcNAc residue of the heptasaccharide.