New flavonoids with 2BS cell proliferation promoting effect from the seeds of Trigonella foenum-graecum L

Antimicrobial Prenylated Isoflavones from the Leaves of the Amazonian Medicinal Plant Vatairea guianensis Aubl

Vatairea guianenis Aubl. (Fabaceae) is an Amazonian medicinal plant species traditionally used for treating skin diseases. In an initial screening, a V. guianensis leaf extract and its subextracts showed antibacterial and antifungal activities. The EtOAc subextract was selected for chemical workup and afforded five known (1-4 and 8) and six undescribed isoflavones, vatairenones C-H (5-7 and 9-11). All isoflavones are prenylated in position C-8, displaying either chain-prenylated (1-7) or ring-closed forms (8-11). The most bioactive compound (3) exhibited in vitro activity against clinically relevant bacteria and fungi with IC₅₀ values ranging from 6.8 to 26.9 μM. Due to its broad antimicrobial activity and low general toxicity, compound 3 is a potential lead compound for structural modifications. The results of the present study support the ethnomedicinal use of V. guianensis in the treatment of dermatological disorders. ¹H NMR spectra of some of the isolated compounds showed intricate signal patterns, which might explain repeated errors in assigning the correct structure of the isoflavonoid B-ring in the literature and which we resolved by higher order spectra simulations.

Multitargeted Effects of Vitexin and Isovitexin on Diabetes Mellitus and Its Complications

BACKGROUND

Till date, there is no known antidote to cure diabetes mellitus despite the discovery and development of diverse pharmacotherapeutic agents many years ago. Technological advancement in natural product chemistry has led to the isolation of analogs of vitexin and isovitexin found in diverse bioresources. These compounds have been extensively studied to explore their pharmacological relevance in diabetes mellitus. Aim of the Study. The present review was to compile results from in vitro and in vivo studies performed with vitexin and isovitexin derivatives relating to diabetes mellitus and its complications. A systematic online literature query was executed to collect all relevant articles published up to March 2020.

RESULTS

In this piece, we have collected data and presented it in a one-stop document to support the multitargeted mechanistic actions of vitexin and isovitexin in controlling diabetes mellitus and its complications.

CONCLUSION

Data collected hint that vitexin and isovitexin work by targeting diverse pathophysiological and metabolic pathways and molecular drug points involved in the clinical manifestations of diabetes mellitus. This is expected to provide a deeper understanding of its actions and also serve as a catapult for clinical trials and application research.

Identification of C-geranylated flavonoids from Paulownia catalpifolia Gong Tong fruits by HPLC-DAD-ESI-MS/MS and their anti-aging effects on 2BS cells induced by H2O2

The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C (1) and five known C-geranylated flavanones (2–6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CH₂Cl₂ extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by H₂O₂. Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone (3) and paucatalinone A (5) were the potent anti-aging agents in the premature senescent 2BS cells induced by H₂O₂ and the C-geranyl substituent may be an important factor because of its lipophilic character.

Derrisisoflavones H-K and One Isoflavan Derivative from Derris robusta

Four hitherto unknown prenylated isoflavonoids, named derrisisoflavones H-K (1-4) and one new isoflavan, namely 6-hydroxyisosativan (5), were isolated from the ethanol extract of Derris robusta. Their structures were elucidated on the basis of extensive spectroscopic studies. To our knowledge, derrisisoflavones J (3) and K (4) are the first examples of hydroxyethylated isoflavonoid.

NMR spectroscopic method for the assignment of 3,5-dioxygenated aromatic rings in natural products

In recent years, certain "new" naturally occurring compounds (1-28) with 3,5-dioxygenated aromatic rings have been reported. A comparison of the NMR data of these compounds with the data of four model compounds (A-D) indicated that the structures of these "new" compounds were erroneous. The reason for the incorrect elucidation of the structures of 1-28 was attributed to "deceptively simple" (1)H NMR spectra, which displayed two broad singlets with integrations of 1:2 for H-2 and H-5, H-6, respectively. To expose the misleading results from the spectra, serial (1)H NMR experiments on compounds A-D were performed using various deuterated solvents and temperatures. The results revealed separated proton signals for the ABX system in certain deuterated solvents. Additionally, the characteristic differences between 3,4- and 3,5-dioxygenated aromatic rings in their (13)C NMR spectra are summarized based on our experiment and data reported. This approach is useful for analyzing the patterns of dioxygenated aromatic rings in natural products, especially when "deceptively simple" (1)H NMR spectra are displayed.

Ethnomedicinal and phytochemical review of Pakistani medicinal plants used as antibacterial agents against Escherichia coli

Medicinal plants have always been part of human culture and have the potential to cure different diseases caused by microorganisms. In Pakistan, biologists are mainly focusing on plants’ antimicrobial activities against Escherichia coli due to its increasing resistance to antibiotics. In total, extracts from 34 ethnomedicinally valuable Pakistani plants were reported for in-vitro anti-E. coli activities. Mostly methanolic extracts of medicinal plants were used in different studies, which have shown comparatively higher inhibitory activities against E. coli than n-hexane and aqueous extracts. It has been found that increasing concentration (mg/ml) of methanolic extract can significantly increase (p < 0.01) anti-E. coli activities. Not all medicinal plants are extracted in solvents others than above, which should also be tested against E. coli. Moreover, medicinal plant species must be fully explored phytochemically, which may lead to the development of new drugs.

Effect of fenugreek seed extract on adriamycin-induced hepatotoxicity and oxidative stress in albino rats

The purpose of this work was to evaluate the effect of aqueous extract of fenugreek seeds against hepatotoxicity induced in albino rats by the anticancer drug adriamycin (ADR). Animals were given single dose of ADR (10 mg/kg body weight) and were killed after 2 and 4 weeks. Liver of ADR-treated animals showed histopathological and biochemical alterations. The histopathological changes include hepatic tissue impairment, cytoplasmic vacuolization of the hepatocytes, congestion of blood vessels, leucocytic infiltrations and fatty infiltration. Moreover, the expression of proliferating cell nuclear antigen was increased in ADR-treated rats. The liver enzymes, aspartate aminotransferase (ALT) and alanine aminotransferase (AST) were increased in the sera of treated rats. Moreover, ADR significantly increased the concentration of malondialdehyde (MDA) and decreased the activities of superoxide dismutase (SOD) and catalase (CAT) in hepatic tissue. Treating animals with ADR and aqueous extract of fenugreek (0.4 g/kg body weight) seeds led to an improvement in histological and biochemical alterations induced by ADR. The biochemical results showed that AST and ALT appeared normal together with reduction in the level of MDA (lipid peroxidation marker) and increase in SOD and CAT activities. It was concluded from this study that the aqueous extract fenugreek seeds has a beneficial impact on ADR-induced hepatotoxicity due to its antioxidant effect in albino rats.

Effect of fenugreek seeds extract on cyclophosphamide-induced histomorphometrical, ultrastructural and biochemical changes in testes of albino mice

Cyclophosphamide (CPA) is an anticancer drug used in the treatment of a variety of neoplastic lesions. On the other hand, treatment with CPA was accompanied by different toxic effects on different body organs. The present work was conducted to study the effect of fenugreek seed extract on histomorphometrical and ultrastructural changes induced by CPA in testes of albino mice. Twenty animals were given CPA (7.0 mg/kg body weight) three times/week orally for 8 weeks and were killed after 4 and 8 weeks. Testis of CPA-treated mice showed many histological alterations including appearance of irregular seminiferous tubules, reduction in the number of all spermatogenic cells, degeneration of Leydig cells and appearance of intertubular hemorrhage. Concerning the ultrastructural changes, abnormalities in spermatogonia (A and B), spermatocytes, round and elongated spermatids were observed. Degenerated Sertoli cells and degenerated interstitial tissue with abnormal Leydig cells were also seen. Moreover, administration of CPA to animals significantly increased malondialdehyde (MDA, lipid peroxidation marker) and decreased superoxide dismutase (SOD) and catalase (CAT). These changes were time-dependent. Treating animals with CPA and fenugreek seed extract (0.4 g/kg body weight) led to an improvement in the histological and ultrastructural pictures of the testis together with reduction in the level of serum MDA and increase in the activities of serum SOD and CAT. In conclusion, the results of the present work indicated that fenugreek had ameliorative effect against testis damage induced by CPA and this may be mediated by its potent antioxidant activities.

Cloning and functional characterization of a caffeic acid O-methyltransferase from Trigonella foenum-graecum L

A cDNA encoding an O-methyltransferase (namely FGCOMT1) was identified from the medicinal plant Trigonella foenum-graecum L. The FGCOMT1 enzyme is a functional caffeic acid O-methyltransferase (COMT) and is localized in the cytosol. Kinetic analysis indicated that FGCOMT1 protein exhibited the highest catalyzing efficiency towards 5-hydroxy ferulic acid and caffeic acid as substrates, but did not possess the abilities to methylate either quercetin or tricetin in vitro. Furthermore, transformation of Arabidopsis loss-of-function Atomt1 mutant with a FGCOMT1 cDNA partially complements accumulation of sinapoyl derivatives but did not function to produce the major methylated flavonol isorhamnetin in seeds. The results from this study indicated that FGCOMT1 is a COMT with substrate preference to monomeric lignin precursors but is not involved in the flavonoid methylation in T. foenum-graecum L.