Antimicrobial activities of methanolic extract of Carissa opaca roots and its fractions and compounds isolated from the most active ethyl acetate fraction

Objective: To study the antibacterial and antifungal activities of methanolic extract of roots of Carissa opaca and its fractions in hexane, chloroform, ethyl acetate, n-butanol and water, and the isolated compounds.Methods: The zones of inhibition of the samples against test microorganisms were determined by agar well diffusion method. Minimum inhibitory concentrations of the samples were determined by agar well dilution method. Test microorganisms included four standard bacteria [Bacillus subtilis ATCC 6633(B. subtilis), Escherichia coli ATCC 8739(E. coli), Pseudomonas aeruginosa ATCC 9027(P. aeruginosa), and Staphylococcus aureus ATCC 6538], two standard fungi [Candida albicans ATCC 10231(C. albicans)] and Aspergillus niger, and six clinical isolates(B. subtilis, E. coli, P. aeruginosa, Staphylococcus aureus, Salmonella typhi and Enterobacter cloacae). The most active fraction was investigated to isolate compounds. The chemical compounds isolated from the ethyl acetate fraction were identified by gas chromatography-mass spectrometer, high performance liquid chromatography and liquid chromatography-mass spectrometer.Results: E. coli, P. aeruginosa, and C. albicans were the most susceptible. Less polar fractions exhibited stronger efficacy than polar ones, and ethyl acetate fraction proved to be the most potent. Zones of inhibition of hexane, chloroform and ethyl acetate fractions, and amoxil against C. albicans were 19.96, 22.01, 23.10 and 19.20 mm, respectively. Ethyl acetate faction was the most toxic to all the test microorganisms, with minimum inhibitory concentrations of 8.0, 7.8 and 7.78 μg/m L against P. aeruginosa, C. albicans and B. subtilis, respectively. Isolated compounds, limonene, 2'-hydroxyacetophenone, vanillin, naphthalenone, 2,3,3-trimethyl-2-(3-methylbuta-1,3-dienyl)-6-methylenecyclohexanone, 2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester, β-sitosterol, vitamin E, rutin, quercetin, lupeol, epigallocatechin, showed considerable antimicrobial activities against test microorganisms.Conclusions: The roots of Carissa opaca contain compounds with significant antimicrobial potential.

The Genus Carissa:An Ethnopharmacological,Phytochemical and Pharmacological Review

Carissa L.is a genus of the family Apocynaceae,with about 36 species as evergreen shrubs or small trees native to tropical and subtropical regions of Africa,Asia and Oceania.Most of Carissa plants have been employed and utilized in traditional medicine for various ailments,such as headache,chest complains,rheumatism,oedema,gonorrhoea,syphilis,rabies.So far,only nine Carissa species have been phytochemically studied,which led to the identification of 123 compounds including terpenes,flavonoids,lignans,sterols,simple phenolic compounds,fatty acids and esters,and so on.Pharmacological studies on Carissa species have also indicated various bioactive potentials.This review covers the peer-reviewed articles between 1954 and 2016,retrieved from Pubmed,ScienceDirect,SciFmder,Wikipedia and Baidu,using“Carissa”as search term(“all fields”)and with no specific time frame set for search.Fifteen important medicinal or ornamental Carissa species were selected and summarized on their botanical characteristics,geographical distribution,traditional uses,phytochemistry,and pharmacological activities.

Psychoactive Chemical Constituents of Carissa edulis (Forssk.) Vahl Roots and Its Safety Limits in Folk Treatment: Benzodiazepines Analogous

Carissa edulis Vahl is well known in Sudanese herbal medicine,commonly used for treatment of epilepsy,headache,chest pains,rheumatism,skin lesions,mania and other psychoactive diseases.The investigations of the safety use for psychoactive purposes in Sudanese healing traditions and identifying secondary metabolites of the plant extracts are the key steps towards determination of appropriate medicinal doses.Therefore,one of the chemical constituents was isolated and structurally identified by 1H-NMR and LC-MS.With the aim of evaluating Carissa edulis folk random uses,the isolated compound was compared with reference artificial drugs Lormetazepam,a potentially toxic compound.Structure investigations confirm that the isolated product was benzodiazepines analogous 7-chloro 1,4-benzodiazepine-2-ones.It is important to know the potential toxicity of certain plant in order to assess the therapeutic effect of it,as these are slight distinctions between the medicinal and toxic doses.In general the results obtained justify the use of the roots of Carissa edulis in traditional medicine for the treatment of some psychiatric diseases.