Evaluation of Antioxidant,Anti-Inflammatory and Antityrosinase Potential of Extracts from Different Aerial Parts of Rhanterium suaveolens from Tunisia

The genus Rhanterium (Asteraceae) is a widely distributed medicinal plant throughout western North Africa and some Rhanterium species are used in folk medicine. The aim of research was to investigate methanolic extracts from different parts (flowers, leaves, and stems) of Tunisian Rhanterium suaveolens as potential sources of bioactive products useful for healthy purposes. In particular, were analyzed the phenolic composition of these extracts and their antioxidant, anti-inflammatory, and anti-tyrosinase properties. The phytochemical analyses were performed using standard colorimetric procedures, HPLC-DAD and HPLC-DAD-ESI-MS. Then, several in vitro cell-free assays have been used to estimate the antioxidant/free radical scavenging capability of the extracts. Moreover, in vitro, and in vivo anti-melanogenesis activities of these extracts were tested, respectively, with the tyrosinase inhibition assay and the Zebrafish embryo model. Finally, the anti-inflammatory potential of these extracts in an in vitro model of acute intestinal inflammation in differentiated Caco-2 cells was evaluated. The R. suaveolens extracts under study appeared particularly rich in flavonols and hydroxycinnamic acids and all extracts appeared endowed with good antioxidant/free radical scavenging properties, being the flower extracts slightly more active than the others. Moreover, R. suaveolens flowers extract was able to inhibit in vitro tyrosinase activity and exhibited bleaching effects on the pigmentation of zebrafish embryos. Furthermore, all extracts showed good anti-inflammatory activity in intestinal epithelial cells as demonstrated by the inhibition of TNF-α-induced gene expression of IL-6 and IL-8. R. suaveolens aerial parts may be considered as a potential source of whitening agents, as well as of agents for the treatment of disorders related to oxidative stress and inflammation.     

Phytochemical Compounds of Euphorbia bivonae Extract and Their Cytotoxicity Effects on the Lethality of Brine Shrimp Artemia salina and Embryonic Kidney (HEK293) Cells

In this research article, we investigated the effect of Euphorbia bivonae extract compounds on the lethality of brine shrimp Artemia salina and on embryonic cell lines (HEK293) proliferation. Our GC/MS analysis revealed that the E. bivonae ethanolic extract contained essentially sitosterol, euphol, and lupeol. The 24-h LC50 was determined using the probit analysis method (LC50=357.11 mg l⁻¹). Depending on this cytotoxicity test result, E. bivona extract induced a significant increase in Superoxide Dismutase (SOD), Catalase (CAT), Glutathione-Peroxidase (GPx) activities, and lipid peroxidation (LPO) in A. salina larvae. In addition, the cytotoxicity effect of this extract had proved against the HEK293 cell lines in vitro. We suggest that the three compounds of E. bivonae extract (sitosterol, euphol, and lupeol) are the most responsible for this cytotoxicity. The possible application of this extract as an alternative natural antiproliferative is considered.