Phytochemical Studies on Periploca angustifolia L.

Abstract

This work has been carried out to investigate the chemical constituents and biological activties of Periploca angustifolia L., of family Asclepiadaceae (Apocynaceae). The nutritive value reached its maximum value in winter, which is still relatively low than other common food staple this due to high moisture content, carbohydrates and fats in winter accompanied by enough protein. Elemental analysis of macro-and micronutrients side by side with other elements were carried out. The plant contained 12 free amino acids (arginine was the highest detected free amino acid) and 14 protein amino acids (aspartic acid was the highest detected combined amino acid), 16 free and 11 combined sugars (inulin was the highest detected free and combined sugar). While unsaponifiable matter contains 11 hydrocarbons, 3 sterols besides 8 unknown compounds, the highest concentration of hydrocarbon and sterol were n-decane and α-amyrin, respectively. On the other hand, saponifiable matter revealed the presence of 6 saturated fatty acids and two unsaturated fatty acids. Identification of 30 compounds from ethanolic extract of the plant were detected by using GC-MS. Identification of flavonoid and phenolic compounds using HPLC was done. Isolalation and identification of flavonoids and phenolic compounds, using different chromatographic methods revealed the presence of six flavonoid compounds namely, isorhamnetin-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside, rutin (quercetin-3-O-α-L-rahamnopyranosyl-(1```-6``)-β-D-glucopyranoside, isorhamnetin-3-O-β-glucoside, quercetin-3-O-β-D-glucopyranoside, quercetin-3-O-α-L-rhamnopyranoside, quercetin and 3 phenolic compounds namely, di-(2-ethylhexyl) phthalate (DEHP), diisooctyl phthalate (DOP) and bis (7-methyloctyl) phthalate ester) (Diisononoyl phthalate, DINP). Identification of these compounds was carried out using Rf-values, UV, 1H-NMR, 13C-NMR and MS spectral analysis. Biological activity divided into two parts, first in vitro; which include the study of the total extract of the plant and its successive extracts against antimicrobial activity, the ethyl acetate and ethanolic 50% extract showed the best effect on all tested bacterial and fungal strains with MIC ranges observed from 70 to 90 mg/ml. The strongest DPPH radical scavenging activity was exhibited by ethanol 50% extract, followed by total extract of plant with IC50 = 45.09 and 46.96 µg /ml, respectively. The ethyl acetate extract was recorded highly cytotoxic effect against MCF7, HCT116 and HEPG2, chloroform extract were recorded highly cytotoxic effect against T47D and petroleum ether extract recorded highly cytotoxic effect against HELA. Second part, in vivo studies, the acute toxicity examination for crude ethanol extract of the plant indicated that, the extract under investigation is non-toxic and safe up to 5 g/kg b.wt. It is shows potent anti-inflammatory, anti-ulcer, diuretic and anti-diabetic activities. Key Words: Asclepiadaceae, Periploca angustifolia L. chemical constituents, flavonoids and biological activities.