Phytochemical screening, cytotoxicity, antimicrobial and anthelmintic activity of medical plants used in the reatment of lymphatic filariasis in the Eastern Cape, South Africa

[摘要] Lymphatic filariasis is a disease caused by parasitic filarial nematodes that causeexcessive swelling of the limbs, genitalia and breasts due to the distraction of thelymph system. This results in accumulation of lymph and lymphoedema. This diseaseis one of the neglected tropical diseases found in 38 African countries.In South Africa, there is no complete system for treatment of th is filarial disease. Manypatients tend to opt for traditional help to alleviate the suffering caused by the disease.This research was aimed at identifying medicinal plants used as ethnomedicine fortreating lymphatic filariasis and to assess the in vitro antimicrobia l, antifungal, antimycobacterialand anthelmintic activity of these medicinal plants. Six plant species(Platycarpha glomerata , Euphorbia gorgonis, Ricinus communis, Ledebouria sp.,Rumex obtusifolius and Tulbaghia alliacea) were collected from Raymond Mhlaba andlntsika Yethu municipal areas of the Eastern Cape Province with the assistance oftraditional healers and herbalists. Plant extracts were extracted with methanol,ethanol, water and acetone and screened for the presence of phytochemicalcomponents, antimicrobial, anthelminthic and cytotoxic properties. The organic solvent extracts of R. communis displayed good inhibitory propertiesagainst K. pneumoniae, S. aureus, E. coli and B. pumilus with MIC values rangingbetween 0.098 mg/ml and 1.56 mg/ml. All the extracts of P. g/omerata effective lyinhibited the growth of the bacterial strains with MIC values ranging from 0.098 to 1.56mg/ml except the aqueous extract which displayed poor activity against K.pneumoniae with an MIC value of 12.5 mg/ml. All the extracts of T. al/iacea showedexcellent inhibition of bacterial strains with MIC values ranging between 0.098 and1.56 mg/ml. The best activity was also observed with the organ ic solvent extracts ofE. gorgonis by inhibiting the bacterial growth at lowest concentrations of 0.098 and0.195 mg/ml.The best antifungal inhibition against C. albicans was displayed by the organic solventextracts of T. alliacea, R. obtusifolius, Ledebouria sp. and R. communis with MICvalues ranging from 0.098 mg/ml to 1.56 mg/ml. with 50 % mortality while only the 0.5 mg/ml of T. alliacea and 1 mg/ml of P. glomerataacetone extracts exhibited good activity against S. equinus.This study has shown that medicinal plants assessed in this study have strong in vitroantibacterial, antifungal, anti-mycobacterial and anthelmintic efficacy which indicatesthat they are capable of acting against lymphatic filarial parasite infection. Theseobservations are in agreement with indigenous knowledge provided by traditionalhealers. However, further in vivo studies using mammalian models are required inorder to give conclusive evidence that these medicinal plant extracts can be usedbeyond reasonable doubt for treatment of lymphatic filariasis.

[发布机构] University of the Free State