UPLC-PDA-ESI-MS/MS ANALYSIS, ISOLATION OF CHEMICAL CONSTITUENTS, CYTOTOXIC, ANTIOXIDANT, ANTIVIRAL AND ANTIMICROBIAL ACTIVITIES OF THE AERIAL PARTS OF LYCIUM SHAWII ROEM. & SCHULT

*Wafaa H. B. Hassan and Rehab H. Abdallah

ABSTRACT

Phytochemical investigation of petroleum ether and ethyl acetate fractions of the aerial parts of Lycium shawii Roem. & Schult led to isolation of seven known compounds including vanillic acid (1), luteolin (2), kaempferol (3), Diosmetin- 7- O- β – D – glucopyranosyl - (1'''→ 6'') – β – D – glucopyranoside (4), rutin (5), β-sitosterol (6) and β-amyrin (7). Their structures were established on the basis of spectroscopic methods including MS, 1D and 2D NMR data and through comparison with published literatures. To the best of our knowledge compounds 1 - 4 were isolated for the first time from Lycium shawii. UPLC-PDA-ESI-MS/MS analysis in positive and negative modes were applied for the identification and chemical characterization of the phenolic compounds of the ethyl acetate fraction. It showed the presence of 32 compounds including phenolic acids, flavonoidal glycosides, flavonoid aglycones, epigallocatechin derivatives and polymethoxylated flavonoids. Biologically, the cytotoxic activity against A-549 (lung carcinoma), HepG-2 (liver carcinoma) and MCF-7 (breast cancer) cell lines were evaluated for petroleum ether, chloroform, ethyl acetate and butanol fractions of L. shawii. All the tested fractions showed significant activity and the most active was petroleum ether fraction with IC50 5.01, 7.12, and 9.03μg/ml respectively. While the butanol fraction was more effective as antiviral agent against HAV-10 virus than ethyl acetate and petroleum ether fractions. In addition, the chloroform and ethyl acetate fractions exhibited DPPH scavenging potential stronger than that exerted by positive standard, ascorbic acid, with IC50 values of 7.6, 10.9 and 14.2 μg/ml respectively. However the petroleum ether fraction was inactive. Moreover, the antimicrobial activity of different fractions showed promising results and the best inhibitory activity was observed with chloroform fraction against Escherichia coli which is significantly stronger than that exerted by Gentamicin with inhibition zone diameters 20.3 mm and 19.9 mm respectively.

Keywords: L. Shawii, UPLC-Mass analysis, phenolic compounds, antiviral, antioxidant, cytotoxic activities.