No abstract

International audienceAllium roseum L. (Alliaceae) endemic mediterranean specie was represented in the North Africa by 12 different taxa. In the present study, chemical composition, antiproliferative, antioxidant and antimicrobial activities of the essential oil extracted from A. roseum var. grandiflorum Briq. bulbs collected in the North of Tunisia were investigated. Chemical characterization has shown methyl methanethiosulfinate as major sulphurous compounds. A. roseum bulbs essential oil provides interesting antiproliferative activity against two human colonic adenocarcinoma HT29 and CACO2 cell lines in dose-dependent manner with a half-maximal inhibition (IC50) of 4.64 µg/mL and 8.22 µg/mL respectively. The antioxidant activity, as determined by FRAP assay, was 285 µmol equivalent Trolox/g of essential oil. The scavenging effect on DPPH radicals of essential oil was estimated as IC50 values at 156 µg/mL. The inhibition of superoxide anion production in a model of cancer cell lines was significant for both lines HT29 and CACO2 with IC50 of 20.25 µg/mL and 29.12 µg/mL respectively. Allium roseum essential oil exhibited antibacterial and antifungal activities with a high effectiveness against Candida albicans given by an MIC value of 0.019 mg/mL. This biological effect appears to be related mainly to the presence of organosulfur compounds

The main objective of this research was to study the biological characteristics in terms of antioxidant and antimicrobial activities of Ajuga iva and determine the best analytical and extraction methods applicable to this specie and studied compounds. A short screening of its nutritional value in terms of chemical composition is also included. A. iva leaves were analyzed for crude protein (CP), cell wall [neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL)], minerals, fatty acids, essential oils, and phenolic compounds. Mature aerial parts of A. iva were randomly collected during the Spring season from Mograne-Zaghouan, Tunisia. Leaves of A. iva contained 13.4 ± 0.4% CP, 26.3 ± 0.35% NDF, 20.2 ± 0.42% ADF, and 5.13 ± 0.21% ADL. Mineral content (13.0 ± 0.45%) was mainly composed of potassium (4.5% g DM) and magnesium (4.25% DM). Leaves of A. iva had linolenic (26.29 ± 0.760%) and linoleic (37.66 ± 2.35%) acids as the main components of the acid profile. Thymol was found to be the most dominant (23.43%) essential oil, followed by 4-vinylguaiacol (14.27%) and linalool (13.66%). HPLC-PDA-ESI-MS/MS analysis pointed out the presence of phytoecdysteroids. Phenolic acids and flavonoids, such as glycosylated derivatives of naringenin, eriodyctiol, and apigenin, were detected in the methanol extract of A. iva leaves. Our results underline the importance of choosing proper extraction methods and solvents to extract and characterize the described compounds profile of A. iva leaves. Results also show A. iva leaves as a potential source of functional ingredients with beneficial health-promoting properties. Overall, leaves of A. iva have low biological activities (antioxidant and antimicrobial activities) with a chemical composition suitable as a feed for ruminants in rangeland pasture. It also has low-grade antibacterial or medicinal characteristics when fed to ruminants.