CHEMICAL PROFILE AND BIOLOGICAL ACTIVITY OF EUGLENA GRACILIS EXTRACTS

TOLIVIA A. A.; CONFORTI V.; CORDOBA O.L.; FLORES M.L

Armação dos Búzios, Rio de Janeiro

Congreso; XIII International Congress of Protistology; 2009

Sociedade Brasileira de Protozoologia

Different extracts of four Euglena gracilis (Klebs) strains developed in vitro (two photosynthetic ph and two bleachedbl) were screened to identify metabolites with potential applications using chemical methods, TLC, SDS-PAGE, and RP-HPLC-DAD. Studies were performed on the exponential and stationary growth phases of E. gracilis commercial strain (UTEX-753) and wild type strain (MAT; isolated from Matanza River, Argentina). The antioxidant and antitumoral activity in vitro were tested. The identification of secondary metabolites showed that all the samples contained steroids. Cardenolids were present only in the exponential phase samples; triterpenes were observed only in exponential phase samples of bleached strains. Tannins were present in all samples on exponential phase (except MAT-ph strain). In contrast, flavonoids were only observed in the stationary phase samples of MAT and UTEX strains, both in its green form. The pigments analysis by RP-HPLC-DAD revealed differences among the native (MAT) and commercial strains (UTEX-753). These have also been characterized in their different growth phases and the effectiveness of the bleached methodology has been demonstrated. The SDS-PAGE results allowed to detect the different glycoconjugates presence in the bleached strains. Chromatographic profiles show the presence of flavonols, in particular those ones derived from quercetin. This is the fisrt work that reports polyphenols and flavonoids production ineuglenoids. In concordance with the presence of polyphenols, the fractions with the highest polarity showed antioxidant activity against DPPH and antitumoral activityin vitro. Antioxidant production in Euglena has been reported, specially related to the presence of carotene, L-ascorbic acid, and tocopherol. Nevertheless, the relation has not been reported between the polyphenols (and other polar compounds) and antioxidant activity in E. gracilis. The antitumoral activity has been previously mentioned in Euglena, but was related to paramylon; this study used extracts without this polysaccharide. Supported by ANPCyT.