Phytochemical Evaluation of Cissampelos Parelra (A. Rich) Engl., Tinospora Oblongifolia { (Engl.)Troupin And Triclisia Sacleuxii (Pierre) Diels for Antiplasmodial and Antibacterial activities

Abstract

Plants provide awide range of useful chemicals for inanaging many ailments. Large numbers of biologically active compounds with wide varieties of structures have been isolated from plants with some developed into drugs. Plants are therefore a promising source of compounds for management of dis~ases or use as templates for designing new' =detivatives with improved properties. This is necessary because infective agents have developed resistance to most of the existing drugs. The plants Cissampelos pare ira. Tinospora oblongifolia and Triclisia sacleuxii are used widely in traditional medicine to manage varieties of ailments including malaria and bacterial infections. [Iheir crude extracts have shown diverse biological activities but the active compounds are not known. This research set out to isolate and characterise the antiplasmodial and antibacterial compounds from the aerial parts Cissampelos pare ira, stems of Tinospora oblongifolia and Triclisia sacleuxii. The crude extracts were subjected to antiplasmodial and antibacterial assays. Antiplasmodial assay were done using a non-radioactive assay technique to determine 50% growth inhibition on cultured parasites. Two parasitic strains, chloroquine (CQ)" sensitive Sierra I (D6) and CQ-resistant Indochina I (W2), of Plasmodium falciparum were grown. Chloroquine and mefloquine were used as positive controls. Staphylococcus aureus Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa were used in the antibacterial assay by disc diffusion assay for the crude extracts and microdilution assay for the isolates. For positive control streptomycin was used. With the exception of the n-hexane extracts, all the other extracts from the three plants displayed moderate to good in vitro antiplasmodial activity. However, the crude extracts had poor selectivity indices with methanol extract of C. pareira displaying the best selectivity index (3.93). All the tested antibacterial strains were susceptible to all the extracts of the three plants with the exception of the n-hexane extracts to which they were resistant. The largest diameter of zone of inhibition (21.4 mm) was observed with n-butanol extract of T. sacleuxii against S. aureus. A bisbenzylisoquinoline alkaloid, isotetrandrine (172),i,two protoberberine alkaloids; palmatine (130) and columbamine (132) two ferrulamides; trans-li-feruloyltyramine (167) and trans-N-caffeoyltyramine (168), three lignans; yangambin (171) syringaresinol (166) and sesamin (170), a cyclitol, epiquercitol (173) an aldehyde, 4-hydrox)'I:"benzaldehyde (165), two sterols; p-sitosterol (164) and stigmasterol (178), a p-carboline alkaloid; 1-(6-hydroxy-l-( 4-hydroxybenzyl)-3,4-dihydro-l H-pyrido[3,4-b [indol- 2(9H)-yl)tetracosan-l-one (sacleuximine),(169) two glucosides; ~-sitosterol glucoside (177) and withanolide E glucoside (183), two esters; 2-(4'-hydroxyphenyl)-ethyl lignocerate (174) and docosyl-3, 4-dihydroxy-trans-cinnamate (175), a ceramide; 2', 3'-dihydroxy-N-{(2S,3S,4R)- 1,3,4-trihydroxyicosan-2-yl} tetracosanamide (176), three triterpenes; lupeol (181), lanosterol (179) and oleanolic: acid (180) and a flavonoid; epicatechin (182), were isolated. Three compounds displayed potent antiplasmodial activity. Compound 172 displayed an IC50 of 0.31\ and 0.11 11M, compound 130 IC50 0[0.19 and 0.83 11M and compound 132 ICso 0[0.98 and o.ie 11M against the CQ sensitive D6 and CQ resistant W2 Plasmodium falciparum strains respectively. They. also displayed good selectivity indices with compound 132 displaying the highest index of 54.75. Compound 166 was the most active antibacterial compound with MlC values ranging frornlO.9 to 14.8 J..lM:Isolation of compound 173 and lignans (166, 170 and 171' are reported for the first time from the genus Triclisia. The compounds 169 and 176 are reporter for the first time. Antibacterial activity of T. sacleuxii and antiplasmodial and antibacteria activitie-Sof T. obl« .ngifolia are reported for the first time. This research validates the use of thes. plants in folk medicine in the management of a variety of ailments. The identified COlTIl- ound are recommended for further development into drugs to help reduce the disease burden.