American Journal of Laboratory Medicine 2017; 2(4): 69-73 http://www.sciencepublishinggroup.com/j/ajlm doi: 10.11648/j.ajlm.20170204.15 ISSN: 2575-3878 (Print); ISSN: 2575-386X (Online) Evaluation of Trypanocidal Activity of Bidens pilosa and Physalis peruviana Against Trypanosoma brucei rhodesiense Lilian Mwende Mwaniki 1 , John Mokua Mose 2, * , Titus Mutwiri 2 , James Mulinge Mbithi 2 1 Biotechnology Research Institute, in Biochemistry Division (Tissue Culture and Protozology Section), Kenya Agricultural and Livestock Research Organization (KALRO), Nairobi, Kenya 2 Department of Medical Laboratory Science, School of Medicine and Health Sciences, Kenya Methodist University, Nairobi, Kenya Email address: mokuajohn4@gmail.com (J. M. Mose) * Corresponding author To cite this article: Lilian Mwende Mwaniki, John Mokua Mose, Titus Mutwiri, James Mulinge Mbithi. Evaluation of Trypanocidal Activity of Bidens pilosa and Physalis peruviana Against Trypanosoma brucei rhodesiense. American Journal of Laboratory Medicine. Vol. 2, No. 4, 2017, pp. 69-73. doi: 10.11648/j.ajlm.20170204.15 Received: January 10, 2017; Accepted: January 20, 2017; Published: October 24, 2017 Abstract: Trypanosomiasis is a protozoan disease that causes death and morbidity to man, and also severely limits livestock productivity in endemic areas. It is caused by different species of trypanosomes that occur in Africa, South America and Asia. Although chemotherapy is the main method of trypanosomiasis control, the few drugs in the market are faced with challenges of drug resistance, high toxicity and very costly. There is also no likelihood of a vaccine to control new outbreaks and there are no new drugs in the market. Herbal medicines are increasingly being used as an alternative solution to the control of trypanosomiasis in endemic areas. These are cost effective and economic friendly. The purpose of this study was to evaluate trypanocidal activity of Bidens Pilosa and Physalis peruviana using in-vitro and in-vivo protocols. The in-vitro trials are carried out using 96 well plates where the trypanocidal activities of the plant extracts were evaluated by calculating the minimum inhibition concentration (MIC). Toxicity of the herbal extract was determined by monitoring survival, weight change, lethargy and difficulty in breathing. Parasitemia development after extract administration was used as parameters to test the test compound for trypanocidal activity. In vitro results revealed that bidens pilosa had the highest activity with an MIC of 125µg/ml after 48 hours of incubation against Trypanosoma brucei rhodensiense isolated from a patient in busia (KETRI 3684). Toxicity results showed that a dosage level of above 1000mg/kg body weight (highest toxicity trial dose used) of bidens pilosa caused clinical signs such as difficulty in breathing, lethargy, raised hair, loss of weight and death within five days. In- vivo results revealed that Bidens pilosa had some trypanocidal effect but did not perform better than the standard drugs. It is recommend that repeat therapy could be done to clear the parasites completely. Combined therapy of bidens pilosa and physalis peruviana was recommended to see if results can create a rationale for combination therapy in elimination of the parasites. This study has showed that Bidens pilosa and Physalis peruviana have trypanocidal potential. Keywords: African Trypanosomosis, Medicinal Plants, Anti-trypanosomal Activity 1. Introduction Sleeping sickness is a disease caused by two subspecies of Trypanosoma brucei, T. b. rhodesiense and T. b. gambiense. The parasites live and multiply extracellularly in blood and tissue fluids of their human host and are transmitted by the bite of infected tsetse flies (Glossina spp). The occurrence of sleeping sickness is restricted to the distribution of tsetse flies which are exclusively found in sub-Saharan Africa between 14°N and 20°S [1]. More than 250 discrete active sleeping sickness foci in 36 African countries are recognized most of which are in rural areas [2]. Trypanosoma b. rhodesiense is found in East and Southern Africa whereas T. b. gambiense occurs in West and Central Africa. The course of sleeping sickness is different depending on the subspecies. Infections with T. b. rhodesiense lead to an