Poster Presenter

Antimicrobial Activity of the Root Bark Extract and Compounds of Terminalia avicennioides
Abdullahi – Mann, J.O. Amupitan, A.O. Oyewale, K. Ibrahim and J.I. Okogun
Nigeria

Ethnopharmacological relevance: Terminalia avicennioides Guill & Perr (Combretaceae) has been used traditionally as herbal remedies for centuries in West Africa for the treatment of several diseases such as gastrointestinal disorders, ulcers, syphilis, dental caries and skin infections, tuberculosis and cough.

Aim of the Study: This study aimed to evaluate the in vitro anti-oxidant, anticancer and antimicrobial activities which support the therapeutic use of T. avicennioides for treating these infectious diseases and to investigate the cytotoxicity of the extracts and the compounds responsible for these selected biological activities.

Materials and Methods: The ethyl acetate and ethanol extracts of T. avicennioides root barks were fractionated using solid phase extraction and purified by column chromatography. Structure elucidation was performed with nuclear magnetic resonance and mass spectrometry. Furthermore, the Brine Shrimp Toxicity test and agar well diffusion technique were employed to evaluate the cytotoxic effects and the antimicrobial activities of the ethyl acetate and ethanol extracts and subsequent compounds respectively.

Results: Cancer and microbial infections are great challenge to human health concern and it is even exacerbated by the growing resistance to the conventional drugs. Researchers have resort to find remedy from plants for cancer and other infectious diseases. In the continuation of this search we have studied the cytotoxic and antimycobacterial effects of the root bark extract of T. avicennioides. Potent cytotoxicity have been found for both PE and EtOAc extracts, but PE extract gave comparatively higher toxic effects against brine shrimp larvae at ED50 (63.7 μg/ml). In fact, from the results (Table 1) the most promising extract was the PE extract which exhibited remarkable toxicity on brine shrimp larvae at ED50 value (63.7 μg/ml;1 22.6-30.6 confidence interval) and EtOAc extract demonstrated moderate toxicity on brine shrimps at ED50 (297 μg/ml; 852.1-140.1 confidence interval) and EtOH extract was inactive at ED50 (> 1000 μg/ml). This result supports its application as a traditional herbal remedy for the treatment of dental caries, ulcer and anthelminthic diseases and particularly to complement treatment of tuberculosis and fungal infections in HIV/AIDS patients in West Africa (Mann, 2007). Root bark extract of T. avicennioides have shown to exhibit antimycobacterial and anticandida activities, factors which substantiate their application as a traditional herbal remedy to complement treatment of tuberculosis and fungal infections in HIV/AIDS patients.

Conclusion: This study provides proof of efficacy of the extracts of T. avicennioides in treating bacterial infections and addition provide evidence of cytotoxic and antimicrobial compounds present in T. avicennioides that might prove its potential medicinal value, but further clinical studies is required.