Identification and characterization of silver nanoparticles from Erythrina indica and its antioxidant and Uropathogenic antimicrobial properties.

The plant Erythrina indica comes under Fabaceae family, mainly used for used in traditional medicine as nervine sedative, antiepileptic, antiasthmatic, collyrium in opthalmia, antiseptic. Current study focused synthesize of silver nanoparticles (AgNPs) by E. indica leaf ethanol extract. The green-synthesized AgNPs underwent characterization using multiple analytical techniques, including UV-visible, FTIR, DLS, SEM, TEM, XRD, and EDX, and estimation of their antioxidant activity and antimicrobial activity. Phytochemical analysis identified alkaloids, tannins, saponins, flavonoids, and phenols as secondary metabolites. The Total Phenol Content (TPC) was determined to be 237.35 ± 2.02 mg GAE-1, indicating a substantial presence of phenolic compounds. The presence of AgNPs was verified through UV-Visible analysis at 420 nm, and FT-IR revealed characteristic phenolic functional groups. DLS analysis indicated a narrow size distribution (polydispersity index - PDI: 3.47%), with SEM revealing spherical AgNPs of approximately 20 nm. TEM showed homogeneous, highly polycrystalline AgNPs with lattice spacing at 0.297. XRD analysis demonstrated crystallinity and purity, with distinct reflection peaks corresponding to miller indices of JCPDS card no. 01 087 1473. In vitro, AgNPs exhibited robust antioxidant activity like; DPPH, ABTS, and H2O2, surpassing E. indica-assisted synthesis. ABTS assay indicated higher antioxidant activity (81.94 ± 0.05%) for AgNPs at 734 nm, while E. indica extraction showed 39.67 ± 0.07%. At 532 nm, both E. indica extraction (57.71 ± 0.11%) and AgNPs (37.41 ± 0.17%) exhibited H2O2 scavenging. Furthermore, AgNPs displayed significant antimicrobial properties, inhibiting Staphylococcus aureus (15.7 ± 0.12 mm) and Candida albicans (10.7 ± 0.17 mm) byfor the concentration of 80 µg/mL. Through the characterizations underscore of the potential of Erythrina indica-synthesized AgNPs, rich in polyphenolic compounds, for pharmacological, medical, biological applications and antipyretic properties.

Metabolomic study of the estrogenic and anti-osteoporotic potential of Erythrina bidwillii leaf.

Erythrina bidwillii Lindl., Leguminosae, constitutes a valuable crop for horticulture and medicine; however, it is rarely investigated. Menopause is a crucial transitional period in women's health. Women worldwide consider the use of phytoestrogens as a safe hormone replacement therapy to alleviate detrimental menopausal symptoms. Thus, the discovery of novel phytoestrogens is highly demanded. The present study aimed to investigate, for the first time, the metabolomic profile and the estrogenic potential of E. bidwillii Lindl. leaf. Ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry and gas chromatography-mass spectrometry metabolite profiling revealed the prevalence of alkaloids, flavonoids, isoflavonoids and fatty acids. Additionally, five erythrinan alkaloids, cristanine A (1), 8-oxoerythraline (2), (+)-erythrinine (3), (+)-erythraline (4) and 8-oxoerythrinine (5), along with the isoflavonoid genistin (6), were isolated. Erythrina bidwillii leaf extract exhibited significant in vivo estrogenic, anti-osteoporotic, anti-hyperlipidemic, hepatoprotective, and nephroprotective activities, utilizing ovariectomized rat model. Moreover, ethyl acetate and hexane fractions possessed significant in vitro estrogeic potential on MCF-7 cell lines. An in silico study of the isolated metabolites revealed that (+)-erythrinine (3) and 8-oxoerythrinine (5) exhibited the highest affinity for ERα and ERß, respectively, modeling them as potential estrogenic lead metabolites. Therefore, E. bidwillii leaf could be employed as promising hormone replacement therapy for postmenopausal women after thorough clinical trials.

Antiangiogenic Pterocarpan and Flavonoid Constituents of Erythrina lysistemon.

The roots of Erythrina lysistemon, growing in Egypt, yielded 24 flavonoid compounds, including 17 pterocarpans, two isoflavanones, one flavanone, two isoflavans, one 2-arylbenzofuran, and an isoflava-3-ene. Nine pterocarpans have not been reported previously (7-9, 11-14, 19, and 20), and 11 are reported here for the first time from this species. Structures were established using HRESIMS, NMR, and circular dichroism techniques. Selected compounds were tested for their ability to block the growth of human retinal endothelial cells and antiangiogenic activity in vitro. The isoflavonoids 5 and 6, and the pterocarpans 1, 2, 4, 20, and 22 demonstrated selective antiproliferative activities on endothelial cells compared to a nonendothelial cell type, with concentration-dependent antiangiogenic effects in vitro against HRECs, a cell type relevant to neovascular eye diseases.

An overview of techniques and strategies for isolation of flavonoids from the genus Erythrina.

Plants in the genus Erythrina is a potential source of chemical constituents, one of which is flavonoids, which have diverse bioactivities. To date, literature on the flavonoids from the genus Erythrina has only highlighted the phytochemical aspects, so this review article will discuss isolation techniques and strategies for the first time. More than 420 flavonoids have been reported in the Erythrina genus, which are grouped into 17 categories. These flavonoid compounds were obtained through isolation techniques and strategies using polar, semi-polar, and non-polar solvents. Various chromatographic techniques have been developed to isolate flavonoids using column flash chromatography, quick column chromatography, centrifugally accelerated thin-layer chromatography, radial chromatography, medium-pressure column chromatography, semi-preparative high-performance liquid chromatography, and preparative high-performance liquid chromatography. Chromatographic processes for isolating flavonoids can be optimized using multivariate statistical applications such as response surface methodology with central composite design, Box-Behnken design, Doehlert design, and mixture design.

Dimeric alkaloids from the barks of Erythrina variegata as well as their occurrence.

Thirteen undescribed dimeric Erythrina alkaloids, named as erythrivarines A1-A13, were isolated from the barks of Erythrina variegata L. and. Their structures were determined on the basis of NMR, UV and mass spectral analyses. Dimeric Erythrina alkaloid with a C-8/8' linkage in erythrivarine A1 was not yet reported. Representative dimers from titled plant were used to prove their occurrence as natural products by LC - MS detection. Additionally, simultaneous investigation enabled us to propose the natural property of seemingly artificial Erythrina alkaloid with acetonyl group.

Metabolite profiling, antifungal, biofilm formation prevention and disruption of mature biofilm activities of Erythrina senegalensis stem bark extract against Candida albicans and Candida glabrata.

The antifungal activity of the 70% ethanol stem bark extract of Erythrina senegalensis (ESB) against different strains and drug resistant clinical isolates of Candida albicans and Candida glabrata were evaluated in the study. The effect of ESB on biofilms as well as its activity in combination with fluconazole, nystatin or caspofungin against the Candida strains were also evaluated. We then evaluated the antifungal activity of a microemulsion formulation of ESB against planktonic and biofilms of the Candida species. UPLC-QTOF-MS2 analysis was then undertaken to identify the phytoconstituents of the extract and UPLC fingerprints developed for the routine authentication as part of quality control measures. ESB exerted strong antifungal activities against C. albicans ATCC 10231 and SC5314 strains, and C. glabrata ATCC 2001 strain with minimum inhibitory concentration (MIC) values from 3.91 to 31.25 µg/mL and minimum fungicidal concentrations (MFCs) that ranged from 62.5 to 250 µg/mL. It also exhibited potent antifungal activities (MIC = 4-64 µg/mL) against a collection of C. albicans and C. glabrata clinical isolates that were resistant to either nystatin or azole antifungals. The formulated ESB demonstrated higher antifungal potency against the C. albicans and C. glabrata strains with MIC values of 3.91-31.25 µg/mL which was the same as the MFC values. The extract and its microemulsion formulation were active against biofilms of the strains of the Candida species inhibiting their biofilm formations (SMIC50 = 16-64 µg/mL) and their preformed biofilms (SMIC50 = 128 ->512 µg/mL). ESB also exhibited synergistic antifungal action with fluconazole and nystatin against C. albicans ATCC 10231 and C. glabrata ATCC 2001 strains in the checkerboard assay. Chemical characterization of the extract revealed the presence of phenolic compounds such as flavonoids and their prenylated derivatives, anthracene glycosides and alkaloids. UPLC Fingerprints of the extract was also developed and validated for routine identification and authentication of the stem bark of E. senegalensis. The study findings have demonstrated that the stem bark of E. senegalensis is as a potential source of bioactive compounds that could be developed as novel antifungal agents.

Evaluation of inorganic phosphate solubilizing efficiency and multiple plant growth promoting properties of endophytic bacteria isolated from root nodules Erythrina brucei.

BACKGROUND: In soils, phosphorous (P) mostly exists in fixed/insoluble form and unavailable for plants use in soil solution, hence it is in scarcity. P is fixed in the form of aluminium, iron and manganese phosphates in acidic soils and calcium phosphate in alkaline soils. Phosphate solubilizing bacteria, the ecological engineers play a pivotal role in the mobilization of fixed forms of P by using different mechanisms. The objectives of this study were to evaluate inorganic phosphate solubilizing efficiency and other multiple plant growth promoting traits of Erythrina brucei root nodule endophytic bacteria and to investigate effects of the selected endophytic bacteria on the growth of wheat plant under phosphorous deficient sand culture at greenhouse conditions. RESULTS: Among a total of 304 passenger endophytic bacteria, 119 (39%) exhibited tricalcium phosphate (TCP) solubilization; however, none of them were formed clear halos on solid medium supplemented with aluminum phosphate (Al-P) or iron phosphate (Fe-P). Among 119 isolates, 40% exhibited IAA production. The selected nine potential isolates also exhibited potentials of IAA, HCN, NH3 and/or hydrolytic enzymes production. All the selected isolates were potential solubilizers of the three inorganic phosphates (Al-P, Fe-P and TCP) included in liquid medium. The highest values of solubilized TCP were recorded by isolates AU4 and RG6 (A. soli), 108.96 mg L-1 and 107.48 mg L-1, respectively at sampling day3 and 120.36 mg L-1 and 112.82 mg L-1, respectively at day 6. The highest values of solubilized Al-P and Fe-P were recorded by isolate RG6, 102.14 mg L-1 and 96.07 mg L-1, respectively at sampling days 3 and 6, respectively. The highest IAA, 313.61 µg mL-1 was recorded by isolate DM17 (Bacillus thuringiensis). Inoculation of wheat with AU4, RG6 and RG5 (Acinetobacter soli) increased shoot length by 11, 17.4 and 14.6%, respectively compared to the negative control. Similarly, 76.9, 69.2 and 53.8% increment in shoot dry weight is recorded by inoculation with RG6, AU4 and RG5, respectively. These nine potential endophytic isolates are identified to Gluconobacter cerinus (4), Acinetobacter soli (3), Achromobacter xylosoxidans (1) and Bacillus thuringiensis (1). CONCLUSION: AU4, RG6 and RG5 can be potential bio-inoculants candidates as low cost agricultural inputs in acidic and/or alkaline soils for sustainable crop production.

Antimycobacterial and anti-inflammatory activities of fractions and substances from Erythrina verna Vell focusing on dual severe TB treatment approach.

Tuberculosis remains a major health problem worldwide. Drug-resistant and hypervirulent Mycobacterium tuberculosis (Mtb) strains can lead to a hyperinflammatory response and necrotic pathology in hyper-reactive individuals that require adjunctive treatment. Plant-derived substances have been investigated for TB treatment, among which flavonoids stand out. We evaluate the anti-Mtb, anti-inflammatory and cytotoxicity activities of fractions and substances 1, 2 and 3 isolated from Erythrina verna through a bioassay guided fractionation. Seven fractions (1, 3-5 and 7-9) obtained from dichloromethane E. verna extract inhibited NO production (IC50 ≤ 15 µg/mL) with none or poor cytotoxic effect, while the fractions 4 and 5 notably reduced TNF-a production. Fractions 4, 6 and 9 suppressed Mycobacterium growth with MIC50 ≤ 20 µg/mL. Fraction 4 was the most potent due to dual biological activities. Erythratidinone and alpinumisoflavone inhibited the growth of Mtb H37Rv and hypervirulent strain in bacterial cultures (MIC50 ≤ 20 µg/mL), with erythratidinone standing out in reducing intracellular growth of Mtb H37Rv (5.8 ± 1.1 µg/mL). Alpinumisoflavone and erythratidinone were capable of inhibiting NO and TNF-α production besides showing significant inhibitory effects against Mycobacterium tuberculosis strains with low toxicity in macrophages. Both substances are promising for further studies focusing on an anti-TB dual treatment approach.

Plantas com ação no sistema nervoso central que constam na relação nacional de plantas medicinais de interesse ao sus (RENISUS) / Plants acting on the central nervous system: review plantas com ação no sistema nervoso central que constam na relação nacional de plantas medicinais de interesse ao sus (RENISUS) / Plantas con acción sobre el sistema nervioso central incluidas en la lista nacional de plantas medicinales de interés para sus (RENISUS)

A depressão é uma doença grave que atinge a população em geral, estudos epidemiológicos estimam que a prevalência da depressão ao longo da vida no Brasil está em torno de 15,5%. Os fatores que desencadeiam o aparecimento da depressão incluem fatores sociais, psicológicos, biológicos e também fatores externos específicos como eventos estressantes, solidão, consumo de álcool e drogas, doenças crônicas e dar á luz (depressão pós-parto). O objetivo da presente pesquisa consistiu em realizar uma revisão bibliográfica sobre as principais plantas medicinais com ação antidepressiva. A ansiedade vem se tornando um dos principais problemas da atualidade, sendo intensificada pela pandemia causada pelo coronavírus, onde constatou-se que durante o pico da pandemia onde os casos confirmados de COVID-19 no Brasil ascenderam de 45.757 para 330.890, e as mortes, de 2.906 para 21.048, o sentimento de tristeza/depressão atingiu 40% dos adultos brasileiros. Os sintomas de depressão podem ser amenizados quando a disponibilidade sináptica de monoaminas são aumentadas, e esse aumento pode ocorrer através da diminuição da metabolização desses neurotransmissores. Neste sentido, busca-se através da farmacoterapia a utilização de antidepressivos que disponibilizem as monoaminas na fenda sináptica. A escolha do fármaco é feita com base nos sintomas da depressão e na boa resposta a uma determinada classe de antidepressivos. Em fevereiro de 2009 o Ministério da saúde lançou a Relação Nacional de Plantas Medicinais de Interesse ao SUS (RENISUS), contendo 71 espécies vegetais que são distribuídas de forma in natura nas unidades básicas de saúde (UBS). Destas, somente três espécies apresentam efeito antidepressivo e ansiolítico comprovados na literatura sendo Matricharia chamomilla, Erytrinum mulungu e a Passiflora incarnata que também fazem parte da RENISUS. Além destas, outras espécies como a Melissa officinalis, Lippia alba, Valeriana officinalis e Piper methysticum são utilizadas pela população para tratar ansiedade, insônia e depressão, sugerindo desta forma que estas espécies sejam incluídas na RENISUS.

Depression is a serious disease that affects the general population, epidemiological studies estimate that the prevalence of depression throughout life in Brazil is around 15.5%. The factors that trigger the onset of depression include social, psychological, biological and also specific external factors such as stressful events, loneliness, alcohol and drug consumption, chronic diseases and giving birth (postpartum depression). The objective of the present research was to carry out a literature review on the main medicinal plants with antidepressant action. Anxiety has become one of the main problems of today, being intensified by the pandemic caused by the coronavirus, where it was found that during the peak of the pandemic where confirmed cases of COVID-19 in Brazil rose from 45,757 to 330,890, and deaths, from 2,906 to 21,048, the feeling of sadness/depression reached 40% of Brazilian adults. Symptoms of depression can be alleviated when synaptic availability of monoamines is increased, and this increase can occur through decreased metabolization of these neurotransmitters. In this sense, the use of antidepressants that make monoamines available in the synaptic cleft is sought through pharmacotherapy. The choice of drug is based on symptoms of depression and good response to a particular class of antidepressants. In February 2009, the Ministry of Health launched the National List of Medicinal Plants of Interest to the SUS (RENISUS), containing 71 plant species that are distributed in natura form in basic health units (UBS). Of these, only three species have antidepressant and anxiolytic effects proven in the literature, being Matricharia chamomilla, Erytrinum mulungu and Passiflora incarnata, which are also part of RENISUS. In addition to these, other species such as Melissa officinalis, Lippia alba, Valeriana officinalis and Piper methysticum are used by the population to treat anxiety, insomnia and depression, thus suggesting that these species are included in RENISUS.

Los estudios epidemiológicos estiman que la prevalencia de la depresión a lo largo de la vida en Brasil es de alrededor del 15,5%. Los factores que desencadenan la aparición de la depresión son sociales, psicológicos, biológicos y también factores externos específicos, como los acontecimientos estresantes, la soledad, el consumo de alcohol y drogas, las enfermedades crónicas y el parto (depresión posparto). El objetivo de esta investigación fue realizar una revisión bibliográfica sobre las principales plantas medicinales con acción antidepresiva. La ansiedad se ha convertido en uno de los principales problemas de la actualidad, intensificándose por la pandemia causada por el coronavirus, donde se encontró que durante el pico de la pandemia donde los casos confirmados de COVID-19 en Brasil aumentaron de 45.757 a 330.890, y las muertes, de 2.906 a 21.048, el sentimiento de tristeza/depresión alcanzó el 40% de los adultos brasileños. Los síntomas de la depresión pueden aliviarse cuando se aumenta la disponibilidad sináptica de las monoaminas, y este aumento puede producirse mediante una disminución de la metabolización de estos neurotransmisores. En este sentido, se busca a través de la farmacoterapia el uso de antidepresivos que hagan disponibles las monoaminas en la hendidura sináptica. La elección del fármaco se hace en función de los síntomas de la depresión y de la buena respuesta a una clase concreta de antidepresivos. En febrero de 2009, el Ministerio de Salud lanzó la Lista Nacional de Plantas Medicinales de Interés para el SUS (RENISUS), que contiene 71 especies de plantas que se distribuyen in natura en unidades básicas de salud (UBS). De ellas, sólo tres especies tienen efectos antidepresivos y ansiolíticos probados en la literatura: Matricharia chamomilla, Erytrinum mulungu y Passiflora incarnata, que también forman parte del RENISUS. Además de éstas, otras especies como Melissa officinalis, Lippia alba, Valeriana officinalis y Piper methysticum son utilizadas por la población para tratar la ansiedad, el insomnio y la depresión, lo que sugiere que estas especies se incluyan en el RENISUS.

Flavanones from Erythrina crista-galli Twigs and Their Antioxidant Properties Determined through In Silico and In Vitro Studies.

Flavonoids are a secondary metabolite group with various bioactivities, such as antioxidants. They are rich in the genus Erythrina, such as Erythrina crista-galli. This research aims to isolate and characterize flavonoids from the twigs of E. crista-galli and determine their antioxidant properties through in silico and in vitro assays. The ethyl acetate extract of E. crista-galli twigs were separated by column chromatography and characterized using spectroscopic methods. Density functional theory (DFT) calculations were performed on the isolated flavonoids and the reference compounds (ascorbic acid and quercetin) to obtain global descriptive parameters and a donor-acceptor map (DAM). We successfully isolated lupinifolin (1) and citflavanone (2) for the first time from E. crista-galli, along with lonchocarpol A (3), which has been discovered previously. The DAM suggests that these flavanones are good antiradicals with effective electron donors. However, they tend to be electron acceptors in methanol. The frontier molecular orbital analysis implies that lupinifolin (1) is a better antiradical than the other flavanones. The DPPH assays show that lupinifolin (1) has the highest antioxidant (antiradical) activity, with an IC50 value of 128.64 ppm. The in silico studies showed similar trends to the in vitro assays using the DPPH method.

A Comparative Analysis of Antimicrobial, Antibiofilm and Antioxidant Activity of Silver Nanoparticles Synthesized from Erythrina Suberosa Roxb. and Ceiba Pentandra.

Biofilm forming bacteria can cause serious health problems that are difficult to combat. Silver nanoparticles (Ag-NPs) synthesized from plant extracts have potential to fight and eradicate biofilmforming bacteria. In the present research, AgNPs were synthesized using leaf and bark extract of Erythrina suberosa Roxb. and Ceiba pentandra L. and their antibiofilm, antioxidant and antibacterial activity was checked. Phytochemical analysis of the plant extracts showed important bioactive compounds such as tannins, saponins, steroids, phenolics, alkaloids, flavonoids and glycosides. The AgNPs were synthesized and confirmed by visual color observation and UV-Vis spectrophotometer. Visual color observation showed that the color of the leaf and bark extracts of E. suberosa and C. pentandra turned into brown. UV-Vis spectra analysis showed absorbance peak range between 430-450 nm. The antioxidant activity of the AgNPs was determined by FRAC (Ferrous reducing antioxidant capacity) assay. Synthesized AgNPs from all sources showed significant antioxidant activity. However, antioxidant activity of E. suberosa AgNPs was significant compared to other sources. Antibacterial activity and biofilm forming assay was analyzed against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The synthesized AgNPs silver nanoparticles showed significant (p ≤ 0.05) antibacterial activity against all the bacteria. The maximum zone of inhibition was found in case of E. suberosa AgNPs bark extract against P. aeruginosa was 20±1.154 mm. The results of biofilm forming assay showed that the AgNPs from all sources significantly (p ≤ 0.05) inhibited the activity of biofilms by all the tested bacteria. From results, it can be concluded that AgNPs synthesized from both plants can be used in developing antimicrobial compounds.

In Vitro Antioxidant and Anticancer Properties of Various E. senegalensis Extracts.

Although Erythrina senegalensis is a plant widely used in traditional medicine in sub-Saharan Africa, its biological properties have been poorly investigated to date. We first characterized by conventional reactions the composition of several stem bark extracts and evaluated in acellular and cellular assays their pro- or antioxidant properties supported by their high phenolic and flavonoid content, particularly with the methanolic extract. The pro- or antioxidant effects observed did not correlate with their IC50 concentrations against five cancer cell lines determined by MTT assay. Indeed, the CH2Cl2 extract and its ethyl acetate (EtOAc) subfraction appeared more potent although they harbored lower pro- or antioxidant effects. Nevertheless, at equipotent concentration, both extracts induced ER- and mitochondria-derived vacuoles observed by fluorescent microscopy that further led to non-apoptotic cell death. LC coupled to high resolution MS investigations have been performed to identify chemical compounds of the extracts. These investigations highlighted the presence of compounds formerly isolated from E. senegalensis including senegalensein that could be retrieved only in the EtOAc subfraction but also thirteen other compounds, such as 16:3-Glc-stigmasterol and hexadecanoic acid, whose anticancer properties have been previously reported. Nineteen other compounds remain to be identified. In conclusion, E. senegalensis appeared rich in compounds with antioxidant and anticancer properties, supporting its use in traditional practice and its status as a species of interest for further investigations in anticancer drug research.

Anti-respiratory syncytial virus and anti-herpes simplex virus activity of six Tanzanian medicinal plants with extended studies of Erythrina abyssinica stem bark.

ETHNOPHARMACOLOGICAL RELEVANCE: Except for few highly pathogenic viruses, no antiviral drug has been approved for treatment of viral infections in humans. Plant extracts, selected based on their ethno-medical use, represent an important source of compounds for the development of novel candidate antiviral drugs. This especially concerns plants with ethnomedical records on their use in treatment of viral infections. AIM OF THE STUDY: To identify and document medicinal plants used by traditional health practitioners (THPs) for treatment of respiratory infections and muco-cutaneous lesions in order to study their antiviral activity including identification of active components and elucidation of mode of antiviral activity. MATERIALS AND METHODS: The ethno-medical survey was performed in the Kagera region of Tanzania. The THPs were asked for plants used for treatment of signs and symptoms of respiratory infections and watery muco-cutaneous blisters in oral and genital regions. The plants identified were successively extracted with n-hexane, ethyl acetate and water, and the extracts assayed for anti-respiratory syncytial virus (RSV), anti-herpes simplex virus 2 (HSV-2), and anti-human parainfluenza virus 2 (HPIV-2) activity in cultured cells. Antiviral components were separated by ethanol precipitation and CL-6B chromatography, and the mode of antiviral activity elucidated by the time-of-addition assay and selection for the virus variants resistant to antiviral plant extract. RESULTS: THPs identified fifteen plants used for treatment of respiratory infections and muco-cutaneous blisters. The water extract, but not n-hexane or ethyl acetate extracts, of six of these plants including Erythrina abyssinica stem bark, inhibited infectivity of two glycosaminoglycan-binding viruses i.e., RSV and HSV-2 but not the sialic acid binding HPIV-2. An activity-guided separation revealed that antiviral component(s) of water extract of E. abyssinica could be precipitated with ethanol. This sample potently and selectively inhibited RSV and HSV-2 infectivity in cultured cells with IC50 values of 2.1 µg/ml (selectivity index >476) and 0.14 µg/ml (selectivity index >7143) respectively. The sample exhibited inhibitory effect on the virus attachment to and entry into the cells by directly targeting the viral particles. Indeed, 10 consecutive virus passages in HEp-2 cells in the presence of this extract selected for a resistant RSV variant lacking the attachment, viral membrane-associated, G protein due to a stop codon at amino acid residue 33 (Leu33stop). Fractionation of the E. abyssinica extract on a CL-6B column revealed that anti-RSV and HSV-2 activity correlated with carbohydrate content. The most pronounced antiviral activity was associated with a carbohydrate containing ingredient of molecular mass of <5 kDa, which may polymerize to antiviral composites of up to 410 kDa. CONCLUSIONS: Altogether, the water extract of six medicinal plants showed anti-RSV and anti-HSV-2 activities. Extended studies of the stem bark of E. abyssinica identified antiviral components that potently and selectively inhibited infectivity of free RSV and HSV-2 particles, a feature of importance in topical treatment of these infections. This observation confirms ethno-medical information concerning the use of E. abyssinica extract for treatment of respiratory infections and herpetic lesions.

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.

A new Kunitz trypsin inhibitor from Erythrina poeppigiana exhibits antimicrobial and antibiofilm properties against bacteria.

Erythrina poeppigiana belongs to Fabaceae family (subfamily Papillionoideae) and is commonly found in tropical and subtropical regions in Brazil. Herein, we described the purification and characterization of a new Kunitz-type inhibitor, obtained from E. poeppigiana seeds (EpTI). EpTI is composed by three isoforms of identical amino-terminal sequences with a molecular weight ranging from 17 to 20 kDa. The physicochemical features showed by EpTI are common to Kunitz inhibitors, including the dissociation constant (13.1 nM), stability against thermal (37-100 °C) and pH (2-10) ranging, and the presence of disulfide bonds stabilizing its reactive site. Furthermore, we investigated the antimicrobial, anti-adhesion, and anti-biofilm properties of EpTI against Gram-positive and negative bacteria. The inhibitor showed antimicrobial activity with a minimum inhibitory concentration (MIC, 5-10 µM) and minimum bactericidal concentration (MBC) of 10 µM for Enterobacter aerogenes, Enterobacter cloacae, Klebsiella pneumoniae, Staphylococcus aureus, and Staphylococcus haemolyticus. The combination of EpTI with ciprofloxacin showed a marked synergistic effect, reducing the antibiotic concentration by 150%. The increase in crystal violet uptake for S. aureus and K. pneumoniae strains was approximately 30% and 50%, respectively, suggesting that the bacteria plasma membrane is targeted by EpTI. Treatment with EpTI at 1x and 10 x MIC significantly reduced the biofilm formation and prompted the disruption of a mature biofilm. At MIC/2, EpTI decreased the bacterial adhesion to polystyrene surface within 2 h. Finally, EpTI showed low toxicity in animal model Galleria mellonella. Given its antimicrobial and anti-biofilm properties, the EpTI sequence might be used to design novel drug prototypes.

Prenylated Isoflavonoids-Rich Extract of Erythrinae Cortex Exerted Bone Protective Effects by Modulating Gut Microbial Compositions and Metabolites in Ovariectomized Rats.

Flavonoids, found in a wide variety of foods and plants, are considered to play an important role in the prevention and treatment of osteoporosis. Our previous studies demonstrated that Erythrina cortex extract (EC) rich in prenylated isoflavonoids exerted bone protective effects in ovariectomized (OVX) rats. The present study aimed to investigate the interactions of gut microbiota with the EC extract to explore the underlying mechanisms involved in its beneficial effects on bone. Sprague-Dawley female rats of 3-months-old were ovariectomized and treated with EC extract for 12 weeks. EC extract reversed ovariectomy-induced deterioration of bone mineral density and bone microarchitecture as well as downregulated cathepsin K (Ctsk) and upregulated runt-related transcription factor 2 (Runx2) and alkaline phosphatase (ALP) in the tibia of OVX rats. Its protective effects on bone were correlated with changes in microbial richness and the restorations of several genera. EC increased the serum circulating levels of acetate and propionate in OVX rats. We conclude that the bone protective effects of EC extract were associated with the changes in microbial compositions and serum short chain fatty acids (SCFAs) in OVX rats.

[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-11ß-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.

Pharmacological characterisation of anticonvulsant effects elicited by erythrartine.

OBJECTIVES: The erythrinan alkaloids erythravine and 11α-hydroxy-erythravine from Erythrina verna (Vell.) have been extensively investigated for their anxiolytic and anticonvulsant effects. Both are structurally similar to the erythrartine that also exhibit anxiolytic effects, but there is no report on its anticonvulsant potential. Since some anxiolytic drugs can be useful in the management of epileptic seizures, we investigated whether erythrartine could prevent seizures induced by different chemoconvulsants. METHODS: Experiments were performed using different concentrations of erythrartine injected via intracerebroventricular in rats submitted to pilocarpine, kainic acid, pentylenetetrazol or picrotoxin-induced seizures. Moreover, the rotarod test was performed to verify the effects of erythrartine on animal motor coordination. RESULTS: Our data showed for the first time that erythrartine prevented the occurrence of seizures induced by all of the chemoconvulsants tested and did not affect locomotor performance neither produced sedative effect on animals. CONCLUSION: Obtained results validate the ethnopharmacological significance of E. verna and provide new information on erythrartine, another erythrinian alkaloid of biotechnological and medicinal interest.

Flavonoids and other Non-alkaloidal Constituents of Genus Erythrina: Phytochemical Review.

BACKGROUND: Genus Erythrina belongs to family Fabaceae, which is widely distributed in tropical and subtropical areas. It has been used in both traditional herbal medicines and pharmacological applications. Original research articles and publications on the overview of alkaloids related to this genus are available, but a supportive systematic review account which highlighted phytochemical aspects of other types of secondary metabolites is currently insufficient. OBJECTIVE: With the utilization of data and information from SCI-Finder, Google Scholar, the Web of Science, Scopus, Science Direct, PubMed, Chemical Abstracts, ACS journals, Springer, Taylor Francis, Bentham Science and IOP Science, the reliable material sources of this systematic review paper were obtained from the literature published from the 1980s to now. CONCLUSION: A vast amount of data showed that the non-alkaloidal secondary metabolites were obtained from genus Erythrina with various classes of chemical structures. Herein, approximately five hundred constituents were isolated, comprising flavonoids, terpenoids, saponins, phytosterols, phenols, arylbenzofurans, coumarins, alcohols, ceramides, mono-sugars and fatty acid derivatives. In agreement with the previous phytochemical reports on the plants of the family Fabaceae, flavonoids reached a high amount in the plants of genus Erythrina. Numerous biological activity investigations such as anti-bacteria, anti-cancer, anti-virus using isolated compounds from Erythrina species suggested that secondary metabolites of Erythrina plants are now becoming the promising agents for drug developments.

Erythrina velutina Willd. alkaloids: Piecing biosynthesis together from transcriptome analysis and metabolite profiling of seeds and leaves.

Introduction: Natural products of pharmaceutical interest often do not reach the drug market due to the associated low yields and difficult extraction. Knowledge of biosynthetic pathways is a key element in the development of biotechnological strategies for plant specialized metabolite production. Erythrina species are mainly used as central nervous system depressants in folk medicine and are important sources of bioactive tetracyclic benzylisoquinoline alkaloids (BIAs), which can act on several pathology-related biological targets. Objectives: In this sense, in an unprecedented approach used with a non-model Fabaceae species grown in its unique arid natural habitat, a combined transcriptome and metabolome analyses (seeds and leaves) is presented. Methods: The Next Generation Sequencing-based transcriptome (de novo RNA sequencing) was carried out in a NextSeq 500 platform. Regarding metabolite profiling, the High-resolution Liquid Chromatography was coupled to DAD and a micrOTOF-QII mass spectrometer by using electrospray ionization (ESI) and Time of Flight (TOF) analyzer. The tandem MS/MS data were processed and analyzed through Molecular Networking approach. Results: This detailed macro and micromolecular approach applied to seeds and leaves of E. velutina revealed 42 alkaloids, several of them unique. Based on the combined evidence, 24 gene candidates were put together in a putative pathway leading to the singular alkaloid diversity of this species. Conclusion: Overall, these results could contribute by indicating potential biotechnological targets for modulation of erythrina alkaloids biosynthesis as well as improve molecular databases with omic data from a non-model medicinal plant, and reveal an interesting chemical diversity of Erythrina BIA harvested in Caatinga.