Occurrence of secondary metabolites in tepals of Asphodelus ramosus L.

Major processes contributing to subtleties of ephemeral flowers of Asphodelus ramosus are related to chemical constituents detected in tepals which expand during cold and wet seasons in the eastern Mediterranean. Luteolin, caffeic acid, chlorogenic, and p-hydroxy-benzoic acids are the main constituents, whereas νalkanes, ketones, and fatty acids appear in low amounts

An overview of anti-diabetic plants used in Gabon: Pharmacology and Toxicology

© 2017 Elsevier B.V. All rights reserved.Ethnopharmacological relevance: The management of diabetes mellitus management in African communities, especially in Gabon, is not well established as more than 60% of population rely on traditional treatments as primary healthcare. The aim of this review was to collect and present the scientific evidence for the use of medicinal plants that are in currect by Gabonese traditional healers to manage diabetes or hyperglycaemia based here on the pharmacological and toxicological profiles of plants with anti-diabetic activity. There are presented in order to promote their therapeutic value, ensure a safer use by population and provide some bases for further study on high potential plants reviewed. Materials and methods: Ethnobotanical studies were sourced using databases such as Online Wiley library, Pubmed, Google Scholar, PROTA, books and unpublished data including Ph.D. and Master thesis, African and Asian journals. Keywords including ‘Diabetes’ ‘Gabon’ ‘Toxicity’ ‘Constituents’ ‘hyperglycaemia’ were used. Results: A total of 69 plants currently used in Gabon with potential anti-diabetic activity have been identified in the literature, all of which have been used in in vivo or in vitro studies. Most of the plants have been studied in human or animal models for their ability to reduce blood glucose, stimulate insulin secretion or inhibit carbohydrates enzymes. Active substances have been identified in 12 out of 69 plants outlined in this review, these include Allium cepa and Tabernanthe iboga. Only eight plants have their active substances tested for anti-diabetic activity and are suitables for further investigation. Toxicological data is scarce and is dose-related to the functional parameters of major organs such as kidney and liver. Conclusion: An in-depth understanding on the pharmacology and toxicology of Gabonese anti-diabetic plants is lacking yet there is a great scope for new treatments. With further research, the use of Gabonese anti-diabetic plants is important to ensure the safety of the diabetic patients in Gabon.Peer reviewedFinal Accepted Versio

Bioactive Compounds of Green Phenolic Extracts Obtained via Microwave-Assisted Extraction of Sideritis Species Grown in Greece

The purpose of the present study was to compare the polyphenolic compounds extracted from five Sideritis species grown in Greece; S. scardica, S. clandestina, S. raeseri, S. euboea, and S. syriaca, using the Microwave-Assisted Extraction (MAE) process. To maximize the extraction yield (EY), total phenolic compounds (TPC), hypolaetin (HYP) and isoscutellarein (ISC), derivative contents (target phenolics), the response surface methodology was used for S. scardica. A Box–Behnken design was undertaken to study the effect of ethanol concentration (30–100%), extraction temperature (40–100 °C), and extraction time (5–25 min) on the responses. The optimal MAE parameters were 87.9% (v/v) ethanol, 25 min, and 100 °C. Under these conditions, there was a good agreement between experimental and predicted values, indicating the reliability of the predictions for Sideritis extracts. Phenolic compounds were then extracted under these conditions, from the five Sideritis species under investigation. The TPC, total flavonoid content (TFC), antioxidant activity based on DPPH, ABTS, and FRAP assays as well as the phenolic profile of different Sideritis extracts, evaluated via HPLC-DAD-MS, were compared. A similar phenolic profile was observed among the five Sideritis species, with HYP and ISC derivatives showing variations in their contents as a function of Sideritis species. MAE Sideritis extracts could be considered green and natural antioxidants for medicinal, cosmetic, and food purposes, accompanied by sustainable approaches

Antimicrobial activity of secondary metabolites isolated from Centaurea spruneri Boiss. & Heldr.

Two coumarins, scopoletin (1) and isoscopoletin (2), two simple phenolic acids, protocatechuic acid (3) and isovanillic acid (4) and one flavonoid, eriodictyol (5) were isolated from the aerial parts of Centaurea spruneri. The structure of the compounds was established by spectroscopic methods. The in vitro antimicrobial activity of the isolated compounds was tested against eight bacteria and eight fungal species, using a microdilution method. All compounds tested showed moderate antibacterial and antifungal activities. Their minimum inhibitory concentrations were in the range 0.655-2.38 µmol ml-1 and their minimal bactericidal concentrations ranged from 0.694 to 4.15 µmol ml-1 against the tested bacterial species. All compounds showed fungistatic activity at 0.259-2.38 µmol ml-1 and fungicidal at 0.69-2.6 µmol ml-1 against all fungi tested.Iz nadzemnog dela Centaurea spruneri izolovana su dva kumarina skopoletin (1) i izoskopoletin (2), dve proste fenolske kiseline protokatehuinska kiselina (3) i izovanilinska kiselina (4) i flavonoid eriodiktiol. Hemijske strukture poznatih jedinjenja su utvrđene korišćenjem 1D i 2D NMR, MS i UV spektroskopskih analiza. U in vitro testu za određivanje antimikrobne aktivnosti izolovanih jedinjenja korišćena je mikrodiluciona metoda. Dobijena jedinjenja testirana su na po osam bakterijskih i gljivičnih vrsta. Sva jedinjenja su imala umerenu antibakterijsku i antifungalnu aktivnost. Minimalna inhibitorna koncentracija testiranih jedinjenja se kretala od 0,655 do 2,38 µmol ml-1, a minimalna baktericidna koncentracija 0,694-4,15 µmol ml-1. Testirana jedinjenja su pokazala fungicidnu aktivnost od 0,259-2,38 µmol ml-1 i fungistatičku 0,694-2,60 µmol ml-1, na sve testirane gljive.Projekat ministarstva br. 14304

Occurrence of secondary metabolites in tepals of Asphodelus ramosus L

Abstract Major processes contributing to subtleties of ephemeral flowers of Asphodelus ramosus are related to chemical constituents detected in tepals which expand during cold and wet seasons in the eastern Mediterranean. Luteolin, caffeic acid, chlorogenic, and p-hydroxy-benzoic acids are the main constituents, whereas alkanes, ketones, and fatty acids appear in low amounts

Neuroprotective activity of Hypericum perforatum and its major components

Hypericum perforatum is a perennial plant, with worldwide distribution, commonly known as St. Johns wort. It has been used for centuries in traditional medicine for the treatment of several disorders, such as minor burns, anxiety, and mild to moderate depression. In the past years, its antidepressant properties have been extensively studied. Despite that, other H. perforatum biological activities, as its neuroprotective properties have also been evaluated. The present review aims to provide a comprehensive summary of the main biologically active compounds of H. perforatum, as for its chemistry, pharmacological activities, drug interactions and adverse reactions and gather scattered information about its neuroprotective abilities. As for this, it has been demonstrated that H. perforatum extracts and several of its major molecular components have the ability to protect against toxic insults, either directly, through neuroprotective mechanisms, or indirectly, through is antioxidant properties. H. perforatum has therefore the potential to become an effective neuroprotective therapeutic agent, despite further studies that need to be carried out.This work was supported by Fundacao para a Ciencia e Tecnologia (FCT), projects PTDC/AGR-ALI/105169/2008, PEst-OE/AGR/UI4033/2014. AO was supported by Escola Superior de Tecnologia da Saude do Porto and Instituto Politecnico do Porto (Programa de Formacao Avancada de Docentes).info:eu-repo/semantics/publishedVersio