Abstract
Objective
Cleome genus belonging to Cleomeaceae family is used as an antidiabetic agent in Egyptian folk medicine. The current study aimed to isolated and identify the active constitutes of two species, Cleome africana and Cleome droserifolia, and to study the biological activities, such as antidiabetic, anti-inflammatory, and hepatoprotective.
Materials and methods
The lipid constituents of two plant species, C. africana and C. droserifolia, were extracted with petroleum ether and fractionated to acetone-insoluble fraction and acetone-soluble fraction. Molecular docking studies were carried out in isolated compounds. Antidiabetic, anti-inflammatory, and hepatoprotective activities of the promising compounds were investigated.
Results and conclusion
The fatty alcohols and hydrocarbons were identified from the acetone-insoluble fraction. C. africana comprises four fatty alcohols, in which tetratetracontanol is the main one, whereas C. droserifolia consists of two fatty alcohols, in which dotriacontanol is the main one. The hydrocarbons include seven compounds, with tritriacontane as the main one in both species. The acetone-soluble fraction was saponified to afford the unsaponifiable fraction, which contains in C. africana a series of n-alkanes from n-C14 to n-C31, representing 93.66%, with n-C22 as the main one, in addition to a sterol fraction, forming 5.13%, in which beta-sitosterol is the main compound, and the fraction of C. droserifolia was found to contain a series of n-alkanes from n-C18 to n-C30, representing 60.46%, in which n-C30 is the main compound, besides sterols, representing about 39.54%, with campesterol as a major compound (12.46%), and finally, a triterpene fraction consisting of alpha-amyrin and beta-amyrin. In addition, fatty acids as a mixture of eight acids (saturated and unsaturated) were found in both species; the major two acids are linoleic acid (38.99%) and palmitic acid (33.05%). Extraction of the glucosinolate (GL) constituents from the methanolic extract of C. africana led to isolation and identification of one compound (G), identified as 3-ethylsulfonyl-2,3-dimethoxypropyl GLs. Enzymatic hydrolysis of the total GLs allowed us to identify eight isothiocyanate and two thione compounds. Molecular docking of compound G with glucosidase enzyme using C-DOCKER protocol resulted in having higher docking scores relative to the lead molecule and the ligand (Glimepiride). Accordingly, molecular docking studies proved that the molecule of G compound has a promising active hits and can be used as antidiabetic through glucosidase inhibitor and also different extracts exhibited an anti-inflammatory and hepatoprotective activity.