Eryvarins F and G, two 3-phenoxychromones from the roots of Erythrina variegata

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.

Anxiolytic and anti-depressant effects of hydroalcoholic extract from Erythrina variegata and its possible mechanism of action

Background

Erythrina variegata has been widely used as a traditional medicine.

Objective

The study was designed to evaluate the anxiolytic and anti-depressant effects of an extract from Erythrina variegata.

Methods

The extract was evaluated for anxiolytic and anti-depressant action using the elevated plus maze, light/dark box, open field, forced swimming and tail suspension tests in mice. The mechanism of action was further elucidated using high-performance liquid chromatography with fluorescence detection methods to assay the levels of five neurotransmitters in brain.

Results

The extract exhibited significant increase in the percentage of the open arms entries and the time spent in the open arms in the elevated plus maze test. The results of the light/dark box test revealed a significant increase in the amount of time spent in the light chamber. Extract- treated mice also produced significant increase in the number of crossings and rearings in the open field test. In the forced swimming and tail suspension tests, the extract was able to promote significant decrease in the immobility time. In addition, the extract significantly altered the levels of five neurotransmitters in the brain tissue.

Conclusion

These findings suggest that Erythrina variegata presents potential anxiolytic and anti-depressant activity, and the mechanism may be related to the alteration of neurotransmitter levels.

Leguminous Plants in the Indonesian Archipelago: Traditional Uses and Secondary Metabolites

Indonesia is one of the richest countries with respect to plants resources. People from various ethnic, language, and religious groups have used the plants as alternative medicines, health foods and beverages for hundreds of years. To establish modern application for these understudied plant resources, ethnopharmacological data from more than 40 leguminous plants in Indonesia, spanning the western to the eastern parts of the Indonesian archipelago, were reviewed. In particular, bioactive secondary metabolites, including flavonoids, were described in detail to promote research into these plants as functional foods, nutraceuticals, and medicines.

Glycybridins A-K, Bioactive Phenolic Compounds from Glycyrrhiza glabra

In an attempt to discover bioactive agents from the herbal medicine Glycyrrhiza glabra (widely known as licorice), 11 new phenolic compounds, glycybridins A-K (1-11), along with 47 known phenolics (12-58) were isolated. Their structures were elucidated on the basis of extensive NMR and MS analyses as well as experimental and computed ECD data. According to the clinical therapeutic effects of licorice, enzyme or cell-based bioactivity screenings of 1-58 were conducted. A number of compounds significantly activate Nrf2, inhibit tyrosinase or PTP1B, inhibit LPS-induced NO production and NF-κB transcription, and inhibit the proliferation of human cancer cells (HepG2, SW480, A549, MCF7). Glycybridin D (4) showed moderate cytotoxic activities against the four cancer cell lines, with IC₅₀ values ranging from 4.6 to 6.6 μM. Further studies indicated that 4 (10 mg/kg, ip) decreased tumor mass by 39.7% on an A549 human lung carcinoma xenograft mice model, but showed little toxicity.

Two New Isoflavanones from the Roots of Erythrina variegata

Two new isoflavanones, eryvarins Y (1) and Z (2), together with three known compounds (3–5) were isolated from the roots of Erythrina variegata. The structures of 1 and 2 were established on the basis of spectroscopic data. The new compounds are peculiar isoflavanones, possessing both a 3-methylbut-2-en-1-yl group and a 2-hydroxy-3-methylbut-3-en-1-yl group. Among the isolates, orientanol E (5) exhibited potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains.

Three new constituents from the roots of Erythrina variegata and their antibacterial activity against methicillin-resistant Staphylococcus aureus

Two new isoflavonoids, eryvarins V and W (1 and 2, resp.), and a new chromen-4-one derivative, eryvarin X (3), along with three known isoflavonoids, 4-6, were isolated from the roots of Erythrina variegata. Their structures were established by spectroscopic analyses. Compound 1 is a rare naturally occurring isoflavanone which possesses a OH group at C(3). Among the new compounds 1-3, 2 exhibited a potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains.

Antifeedants from Chinese Medicinal Herb, Erythrina variegata var. orientalis, Against Maize Weevil Sitophilus zeamais

The screening for insecticidal principles from several Chinese medicinal herbs showed that the stem bark of Erythrina variegata var. orientalis possessed significant feeding deterrence against maize weevils, Sitophilus zeamais. Bioassay-directed fractionation of the stem bark extract of E. variegata var. orientalis resulted in the isolation of two alkaloids, identified as erysopine and erysovine from their spectroscopic data. Erysopine and erysovine possessed antifeedant activity against S. zeamais adults with EC50 values of 108.5 and 89.7 ppm, respectively

Four New Isoflavonoids from the Stem Bark of Erythrina variegata

Bioassay-directed fractionation of the stem bark extract of Erythrina variegata L. has resulted in the isolation of three new isoflavones: 5,4'-dihydroxy-8-(3,3-dimethylallyl)-2''-methoxyisopropylfurano[4,5:6,7]isoflavone (1), 5,7,4'-trihydroxy-6-(3,3-dimethylallyloxiranylmethyl)isoflavone (2), 5,4'-dihydroxy-8-(3,3-dimethylallyl)-2''-hydroxymethyl-2''-methylpyrano[5,6:6,7]isoflavone (3) and a new isoflavanone, 5,4'-dihydroxy-2'-methoxy-8-(3,3-dimethylallyl)-2'',2''-dimethylpyrano[5,6:6,7]isoflavanone (4) together with seven known compounds, euchrenone b10 (5), isoerysenegalensein E (6), wighteone (7), laburnetin (8), lupiwighteone (9), erythrodiol (10), and oleanolic acid (11). The structures were determined on the basis of spectroscopic analyses and chemical evidence. The effect of these compounds on the proliferation of rat osteogenic sarcoma (UMR106) is also reported.