No abstract

The results demonstrated that nine Senecio species possess high antioxidant and antimicrobial activity in accordance with the high amount of phenolic contents in the extracts that might be natural agencies used in many areas such as food, pharmacy and alternative medicine.

The present study was conducted to investigate total phenolic contents, antioxidant and antimicrobial activities of four Senecio L. (Asteraceae). The in vitro antioxidant activities of extracts were evaluated with different antioxidant testing systems. Their antioxidant activities were assessed by phosphomolybdenum reduction, DPPH and β-carotene bleaching assays. The extracts exhibited strong antioxidant activity and high scavenging activities against DPPH free radicals. The extracts exhibited weak to moderate β-carotene bleaching activity. The antimicrobial activity of Senecio extracts was tested against 15 microorganisms using agar diffusion and broth microdilution assays. The extracts were found to be weak to moderate effective against 8 out of the 15 microorganisms tested with minimal inhibitory concentration (MIC) values ranging from 1.5 to 12.5 mg/ml. In conclusion, it can be concluded that Senecio extracts may be considered as natural sources in many industry such as food and pharmacy.

Objectives: In vitro biological activities of methanolic extracts of five Turanecio species have been studied. Materials and Methods: The phenolic compositions of the extracts were evaluated by the Folin- Ciocalteu assay and by HPLC analysis. Antioxidant activities were determined with two in vitro assays namely, DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging assay and phosphomolybdenum assay. The antimicrobial activities of the extracts were evaluated against 13 microorganisms. Results: T. hypochionaeus var. hypochionaeus was showed the highest DPPH inhibition with 88.84% at 100 μg·mL-1. All of the extracts were exerted high total antioxidant activities 128.00- 243.13 mg AAE g-1) and seem to be a promising source of natural antioxidants. The phenolic contents in the extracts varied from 26.17 to 60.99 mg·g-1 as gallic acid equivalent. Chlorogenic acid, caffeic acid and p- coumaric acid were the predominant constituents. The methanolic extracts revealed promising antibacterial activities against most bacteria. No activity was recorded against yeasts tested. Conclusion: The polyphenolic constituents appear to be responsible, at least in part, for the extract’s activities. The present study confirms that tested Turanecio species contains significant source of phenolics have antioxidant and antimicrobial activities and may have therapeutic potential.

A New Method for the Preparation of 5-Acylidene and 5-Imino Substituted Rhodanine Derivatives and Their Antioxidant and Antimicrobial Activities. -Wittig reaction of 4,5-thiazolidinediones and phosphoranes affords a series of 1,3-thiazolidin-4-one derivatives (32 samples) regio-and diastereoselectively. The newly prepared compounds exhibit antimicrobial activity. -(UENGOEREN*, S. H.; ALBAYRAK, S.; GUENAY, A.; YURTSEVEN, L.; YURTTAS, N.; Tetrahedron 71 (2015) 25, 4312-4323, http://dx.