Phytochemical screening, antimicrobial, antioxidant and cytotoxicity activities of bark's crude extracts of Cordia sinensis

Abstract

Cordia sinensis which is known locally as Andrab is a medicinal plant used traditionally in Sudan and in many other countries as an antioxidant, anti-glycation, anti-malarial and anti-inflammatory. This study was aimed to prepare various crude extracts of C. sinensis bark using different polarities of solvent; phytochemical screening, antimicrobial, antioxidant, and cytotoxicity of the bark crude extracts. Bark of C. sinensis was collected from Omdurman area, dried under shade, powdered and then extracted successively with petroleum ether, chloroform, ethyl acetate, and methanol by using shaker apparatus (at room temperature). The phytochemical examinations were carried out for all extracts. The preliminary phytochemical analysis of the bark crude extracts revealed the presence of various amount of flavonoids, tannins, cardiac glycosides, sterols/triterpense, alkaloids and showed no saponins and coumarins. Crude extracts at concentrations 25 and 50 mg/ml were applied against four standard bacteria (Gram positive: Bacillus subtillis and Staphylococcus aureus, Gram negative: Klebsiella and Pseudomonas aeruginosa) and two standard fungi (Candida albicans, Aspergillus niger) using the disc diffusion method assay. The methanolic extract at concentration 50 mg/ml was found to be more active against two types of bacteria (Klebsiella and P. aeruginosa) and showed an intermediate activity against the other two types of bacteria (B. subtillis and S. aureus) and also against the two types of fungi (C. albicans and A. niger). No activity was observed with the three solvents (chloroform, ethyl acetate and petroleum ether) (25 and 50 mg/ml) extracts and the methanolic (25 mg/ml) extract against all the microorganisms tested, except ethyl acetate extract at concentration 50 mg/ml showed intermediate inhibition zone (15 mm) against Klebsiella. All extracts were found to be potent against brine shrimps with moderate LD₅₀. The free radical scavenging activity of the crude extracts was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The antioxidant activity of methanolic extract was the strongest (60%), followed in descending order by ethyl acetate (52%), chloroform (48%), and petroleum ether (32%) extracts. The results showed that higher concentrations are more active than lower concentrations in case of antimicrobial and cytotoxicity activities and also showed that methanolic extract was found to be having potent effect more than other extracts. The study recommends further study for identification of chemical compounds in each extract and specifies the active components that make antimicrobial, cytotoxicity and antioxidant activities of this plant.

Keywords:Cordia sinensis, bark extracts, phytochemical screening, cytotoxicity.