الخلاصة:
The present work is devoted to the phytochemical and biological study of an endemic species
of the septentrional Sahara Fagonia longispina Batt. (Zygophyllaceae) and the chemical
composition and antioxidant activity study of fruit essential oil of Zizyphus lotus (L.) Desf.
(Rhamnaceae).
In a first part, the phytochemical investigation of the species F. longispina using different
chromatographic methods (CC, TLC and HPLC) led to isolation and identification by different
spectroscopic methods (1D and 2D, MS and UV) 18 compounds. Among these isolated
compounds, a new monoterpene ∆-2-carene-6-ol-6-O-(2',6'-diacetyl)-β-D-glucopyranoside,
together with four other monoterpenes, seven flavonoids, four phenolic derivatives and two
sterol.
Moreover, the in vitro free radical-scavenging activity of the all extracts has been investigated
by DPPH test, which have demonstrated that ethyl acetate extract are good sources of
antioxidant compounds. However, all extracts of F. longispina showed no substantial result
compared to the antioxidant activity of ascorbic acid. In addition, the total phenolic and the
flavonoids contents were measured using spectrophotometers methods, the results showed that
the acetate extract has a high content compared to the other extracts. As for antibacterial activity
study, showed that a high antibacterial effect of the ethyl acetate extract.
In a second part, the chemical composition of fruit essential oil Z. lotus has been investigated
by the GC-FID and GC-MS analysis, which led to identified 38 compounds. Fatty acids
represented the major fraction (saturated and unsaturated compounds 67.8 and 11%,
respectively), followed by hydrocarbons (10.8%) and sesquiterpenes (1.1%).These results were
quite different from those obtained previously on the fixed oil of the fruit of this species from
two samples from Algeria.
The antioxidant property of this oil was evaluated using β-carotene bleaching method. The
result indicated the potent antioxidant activity of essential oils from Z. lotus.
