Biomed Res Int. 2014;2014:762397. doi: 10.1155/2014/762397. Epub 2014 Jun 22.

Evaluation of antibacterial, antifungal, and antioxidant activities of safflower natural dyes during flowering.

Salem N1, Msaada K1, Elkahoui S1, Mangano G2, Azaeiz S1, Ben Slimen I1, Kefi S1, Pintore G2, Limam F1, Marzouk B1.

• 1Laboratory of Bioactive Substances, Biotechnology Center in Borj-Cedria Technopol, BP 901, 2050 Hammam-Lif, Tunisia.
• 2Dipartimento di Scienze del Farmaco, Via Muroni, 2307100 Sassari, Italy.

Abstract

Two Carthamus tinctorius varieties (Jawhara and 104) were studied in order to investigate their natural dyes contents and biological activities. Obtained results showed that quinochalcone contents and antioxidant activities varied considerably as function of flowering stages. So flowers at fructification stage contained the highest carthamin content with the strongest antioxidant capacity with all assays (FRAP, DPPH, and chelating power methods).

In parallel, we showed a decrease in the content of precarthamin. The quantitative variation of these molecules could be due to colour change of C. tinctorius flowers.

Correlation analysis indicated that the ABTS method showed the highest correlation coefficients with carthamin and precarthamin contents, that is, 0.886 and 0.973, respectively. Concerning the regional effect, the contents of precarthamin and carthamin varied significantly (P < 0.05) at studied regions with the optimum production given by samples of Beja (902.41 μg/g DW and 42.05 μg/g DW, respectively, at flowering stage).

During flowering, the antimicrobial activity of these two natural dyes increased where the maximum inhibitory effect mentioned with carthamin mainly against E. coli (iz = 25.89 mm) at fructification stage. Therefore, the increased frequency of resistance to commonly used antibiotics leads to the search for new effective natural drugs at food and pharmaceutical industries.

PMID:  25045699