Pharmacognostic and pharmacological aspects of plants genus Allium growing in Georgia

Abstract

editorial reviewedThe genus Allium belongs to the former family Alliaceae (now included in Amaryllidaceae). This genus involves up to 1233 species. Plants of the genus Allium have a long history of traditional uses worldwide. The story of Allium cultivation starts over 4000 years ago in ancient Egypt. Allium species are widely used in Georgian traditional medicine as an antifungal, antiseptic and antibacterial remedy. 36 species of the genus Allium are described in Georgia. Among them, 5 species are endemic to Georgia and 2 to the Caucasus region. The aim of this project was the phytochemical study of secondary metabolites of species of the genus Allium, namely A. saxatile and A. ponticum growing in Georgia. To obtain a crude extract of these plants, powdered plants were extracted with 80% EtOH, using an ultrasonic water bath heated at 50˚C. Dried extracts of each plant were subjected to Diaion HP-20 column chromatography. The mobile phase was H2O-MeOH in gradient condition (100:0; 50:50; 0:100 v/v) and EtOAc to give 4 enriched fractions of each plant (A.S.F1_H2O; A.S.F2_MeOH-50%; A.S.F3_MeOH-100%; A.S.F4_EtOAc; A.P.F1_H2O; A.P.F2_MeOH-50%; A.P.F3_MeOH-100%; A.P.F4_EtOAc). Analgesic, anti-inflammatory and gastroprotective activity of the aforementioned fractions were evaluated in rodents using “Hot plate”, carrageenan-induced paw edema, and ethanol-induced ulcer assays, respectively. A. saxatile total extract reveals analgesic activity reaching its maximum at 60 min after the administration. Differently, A. ponticum total extract revealed faster onset but a shorter duration of action. A similar tendency was observed when studying the efficacy of fractions obtained from total extracts. The fact that the A.S.F3 fraction has even higher activity than the total extract, allows concluding that this fraction contains a compound(s) responsible for the analgesic effect. In the ethanol-induced ulcer model, only crude extract of A. saxatile has a moderate gastroprotective effect. Moreover, the crude extract of A. ponticum revealed ulcerogenic properties increasing the ulcer index over one in control animals. Assessment of anti-inflammatory activity revealed a notable efficacy of A.S.tot and A.P.tot extracts (63.5% and 32.7%, respectively). Similarly, to the analgesic assay, 100% methanolic fraction (A.S.F3) showed pronounced activity. The obtained results will contribute to the phytochemistry of Allium species already studied and give a strong background for further investigation of active fractions to isolate the individual compounds responsible for the detected activity