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Plants used in indigenous medicine for the treatment of trypanosomiasis have been reported to have high medicinal activities. A total of 17 plants consisting of 8 angiosperms and 9 fungi were carefully air dried and the powdered extracts were sequentially extracted with petroleum ether, methanol and water; 78 extracts were obtained and tested in vitro against Trypanosoma brucei brucei and Trypanosoma brucei congolenses. The methanolic extracts of Chrysophyllum albidum seed, Sabaflorida roots, Tapinantus globiferus leaves, Formitopsis pinicola and aqueous extract of Chrysophyllum albidum seed showed highest inhibitory activity at 3.9 µg/ml on both Trypanosoma brucei brucei and Trypanosoma congolense. The qualitative phytochemical screen of these extract revealed the presence of alkaloids, saponins, tannins, cardiac glycosides and steroids. The methanolic extract of Chrysophyllum albidum and Tapinantus globiferus were partitioned separately with hexane chloroform and butanol. The butanolic extract of Chrysophyllum albidum showed highest activity at 3.9 µg/ml. The bioassay guided studies of the butanolic extract led to the recovery of component A, B and C from preparative thin layer Chromatographic studies. The GC-MS of component C revealed the presence of several compounds which include13-Tetradecynoic acid, Hexadecanoic acid, methyl ester, 9,12-Octadecadienoic acid, methyl,9-Tetradecenal, (Z) and1, 3 ,4-thiadiazol-2-amine,5-ethoxy. The aqueous extract of Chrysophyllum albidum and Tapinantus globiferus were synthesized using 1Mm of aqueous Silver nitrate. The synthesized silver nano particles of both plants showed minimum inhibitory activity on both Trypanosoma brucei brucei and Trypanosoma congolense at 0.98 µg/ml. In the in vivo experiment 7 groups of mice were infected with Trypanosoma congolense at the height of parasiteamia such as 107 trypanosomes /ml, groups A1, A2 and A3 were treated with 100, 500 and 1000 mg/kg of butanolic seed extract of C. albidum respectively. While group B1, B2 and B3 were administered 100,500 and 1000 mg/kg of synthesized silver nano particles of seed extract C. albidum respectively; group E was treated with standard drug Diminazine; group F was infected but not treated and G was uninfected and untreated group. The animals were treated for five consecutive days. Animals treated with 1000 mg/kg body weight of synthesised nanoparticles of C. albidum had reduced parasiteamia such 102 and they survived up to the 28th day when the experiment was terminated compared to the untreated group F which culminated in death by day 20 post infection. The prophylactic groups were treated for three consecutive days before begin challenged with the parasites. Animals in group C1and D1 were treated with 50 and 100 mg/kg of butanolic seed extract respectively; animals in group C2 and D2 were treated with 50 and 100 mg/kg of synthesized silver nano particles of seed extract C. albidum. The group treated with 100 mg/kg showed highest activity in that parasitemia did not develop up to the time the experiment was concluded. The synthesized silver nano particles of C. albidum and T. globiferus were characterized. The UV visible spectrum showed that C. albidum revealed surface Plasmon resonance at 450 while that of T. globiferus were observed to be in the range of 350 nm. The Scanning electron microscopy of C. albidum indicate that the silver nanoparticles were predominantly spherical with estimated sizes of between 377 nm-3.97 µm and that of T. globiferusare about 1.75-23 µm. This study has shown that most plant have medicinal potential of various degree of activity. Medicinal plant could be used as an excellent and resourceful green material for the rapid and consistent synthesis of silver nanoparticles which could be useful in different applications. Our findings could be targeted for the promising potential applications including drug formulation and biomedical applications in future.



African trypanosomiasis is an important unicellular blood protozoan parasitic disease of both humans and animals. The disease in animal is commonly called Nagana in Zululand which means powerless, useless, or depressed spirits. It is mainly transmitted cyclically by tsetse fly of Glossina species and mechanically by other biting flies(WHO, 2014). Different species of trypanosomes infects cattle and other ruminants. These include Trypanosoma brucei brucei, Trypanosoma congolense and Trypanosoma viva. The two species infective to humans are Trypanosoma brucei rhodesiense and Trypanosomxa brucei gambiense in humans (Nok and Nock, 2002; WHO, 2014). Nagana has become a major hindrance to livestock production where it thrives in different parts of Sub Saharan Africa restricted to latitude of about 150N and 290S of the equator which covers over 10 million km2(Delespaux,2010).

Reports of drug resistance or treatment failure, to limited classes of available trypanocideshas been on the increase (Shaba et al., 2012). There is a resurgence of the disease in the endemic regions of Africa, where millions of human population and cattle are affected with considerable morbidity and mortality (WHO, 2006; Merck, 2010). Estimated losses in agricultural production as a result of the disease are approximately 3 billion pounds annually (Shimelis et al., 2011; Tesfaheywet and Abraham, 2012).

After continued effort especially in the control of the fly vector, there has been decline in number of new cases. The number of Human African Trypanosomiasis (HAT) casereported in 2012 is about 6, 314 new cases(WHO, 2012).

However, the estimated numberof actual human cases is about 20,000 while the estimated population at risk is 65 million people (WHO, 2014). African Trypanosomiasis remains a disease with unsatisfactory medical control to date. The control of Human African Trypanosomiasis (HAT) continues to rely principally on old expensive medicines such as pentamidine, nitrofurans and arsenicals (Delespaux et al., 2010; Vitouley et al., 2011). In recent times, drug development has led to the production of eflornithine (DMFO) as the only new trypanocide in the last fifteen years and it is only effective in the last stage of Gambian sleeping sickness and its regimen is complex and difficult toapply (Priotto, 2009).

Other molecules such as Homidium, Isometamidium and Diminazene aceturateare are use in treatment of animal infections.Furthermore, the therapeutic and prophylactic use of trypanocides is beset by numerous limitations, including toxicity, scarcity and the development of resistance by parasites (Delespaux et al., 2010). Similarly, the unlimited antigenic variation exhibited by the parasite has hampered the production of effective vaccine. Also the limited availability and affordability of pharmaceutical medicines, emphasizes the need for research in to a more, effective, affordable sources of trypanocides which will easily be accessibleto the rural populace in Africa, who bear most of the disease burden (Wurochekke and Anyanwu, 2012). These have necessitated the search for alternativemedicines against African trypanosomiasis, hence research into natural products.

Plants as sources of natural products have been the basis for medical and traditional treatment for several diseases through much of human history, and such treatments are still widely practiced today.

The World Health Organization (WHO) estimates that 80 percent of the population of some Asian and African countries presently use herbal medicine for some aspect of primary health care (Sherman and Hash 2001; Davis et al., 2004; Moquin, 2009). The most commonly used herbal plants in Africa include Azadiractha indica (neem tree) for the treatment of fever; Magnjfera indica (mango tree) for the treatment of malaria and thypoid fever; Allilum sativum (Garlic) rheumatoid arthritis; Acacia nilotica (Acacia) for migraine and pile; Khaya senegalenses (African mahogany) for irritable bowel syndrome and cancer; Carica papaya (Pawpaw tree) formalaria and typhoid (Sofowora, 1993).A number of African medicinal plants belonging to the angiosperm group have been evaluated for their trypanocidal activity and several reports indicate antitrypanosomal activity exits in some medicinal plants (Hoet et al., 2007; Ibrahim et al., 2008; Shuaibu et al., 2008; Abedo et al., 2013 and Abedo et al., 2015) with minimal toxicity.

Fungi are another group of plant which contain compounds, that can make a contribution to the general health of mankind (Pan et al., 2008). As fungi are widely distributed all over the world, some of them have been used in traditional medicine as analgesics, hemostatic, diuretic, nourishment, anti bechic and antitumor agents (Cragg et al.,1997; Sullivan et al., 2006). Also fungi present a spectrum of biological compounds with activities against virus, cancer and parasites.

These plants contain compounds mainly secondary metabolites such as alkaloids, glycosides, flavonoids, terpenes and coumarins (Jorgensen, 2007). Furthermore various bioactive compounds isolated from extracts of Ethiopian higher fungi showed biological properties such as antiprotozoal, anithelmintic, phytotoxic and brine shrimp lethality activities (Hawksworth, 2006).

Similarly, (Davis et al., 2004) investigated leishmanicidal and trypanocidal activity of the extracts and secondary metabolites of some class of fungi known as basidiomycetes. A naturally occurring purine nucleoside found in some mushrooms showed high degree of activity against Mycobacterium (Pan et al., 2008). Aqueous extracts of mushroom substrate are used in foliar disease control (Kharwar et al., 2011). Based on these facts, this work intends to evaluate extracts of some angiosperms and fungi for anti trypanosomal activity.Research based on this approach can provide both new molecules from promissory secondary metabolites and validation of ethno medical uses of crude extracts or partially fractionated through chemical methods. Natural product chemistry can offer new more molecules which could be used to develop drugs against these diseases (Cravotto et al., 2010; Schmidt et al., 2012; Abbeele and Routureau, 2013).

1.2 Statement of the Research Problem

A large number of angiosperms and fungi are widely used in traditional medications with no scientific evaluation to support claims for potency; whether some of these extract in non-synthesized or synthesized silver nano particles forms, have antitrypanosomal activity is the subject of this investigation.


1.3 Justification

Trypanosomiasis, a disease of major importance in human and animals, has continued to threaten human health and economic development (Priotto, 2009;WHO, 2014). T. b.

gambiense and T. b. rhodesienseaffects hundreds of people in sub-Saharan Africa and are responsible for the death of several hundred per year (Ekanem, 2006).While the animal type causes great economic losses.

Chemotherapy is the most commonly used method of control of the disease. The few existing trypanocides are often associated with severe and toxic side effects (Gehig andEfferth 2008) and require lengthy parenteral administration, lack efficacy and expensive nature of drug(Legros et al., 2002). There is urgent need to source for new, cheap and safe alternative medicines against trypanosomiasis from natural origin.

In African countries where sleeping sickness is endemic, plants have traditionally been used for generations and are still widely used to treat this ailment with possible therapeutic activities, which have not been proved scientifically. Nigeria is greatly influenced by the savannah-forest vegetation which may harbourtsetse fly which is the vector of trypanosomes, thus making the area highly endemic to trypanosomiasis. Traditional medicinein Africa has long been noted for centuries in using medicinal plants in curing human and animal trypanosomal infections (Fang et al., 2011). Natural products derived from plants offer novel possibilities to obtain new drugs that are active against trypanosomes (Abedo et al., 2015).

Some Nigerian medicinal plants have been evaluated for their in vitro trypanocidal activity (Davis et al., 2004; Ekanemetal.,2006); Shuaibu et al., 2008; and in vivo anti-trypanosomal efficacies in mice (Abubakar et al., 2008;Atawodi et al., 2011; Abedo et al., 2015) discovery of these potent anti-trypanosomal extracts from plant has increased the great potentials of plant species to provide lead compounds for the development of new natural drugs for effective treatment of sleeping sickness.

1.4   Aim

To evaluate the anti-trypanosomal activities of extracts of some selected angiosperms:

Annona        muricata,Chrysophyllum         albidum,Saba         florida,         Tapinanthus         Globiferus,Cissus

quadrangellum,Vitellaria     paradoxa,Ficus       capensis,Acanthospermun       hispidum      and

fungi:Calvatia                           cythiforms,Xylaria                           polymorpia,                           Trametes

versivcolor,Fomitopsispinicola,Lepista sordid, Agaricus bohisii,Polyporus sanguineus,Boletus edulis andCantharellus cilariusin vitro, in vivo and alsoto synthesize and characterize silver nanoparticles using most active extract.

1.5    Objectives of the Research

  1. To determine the anti-trypanosomal activities of crude extracts, fractions and silver nano particles of some selected angiosperms and fungi;
  2. To determine the petrochemical properties of crude extract of angiosperm sand fungi being investigated in this study.
  • To determine the bio active molecule from angiosperms and fungi through bio assay guided ratiocination;

iv.To determine the effect of synthesized silver nano particle and non-synthesized extract of angiosperms and fungi on pack cell volume of mice;

  1. To characterize synthesized silver nano particles using extracts of angiosperm and fungi with the highest trypanocidal activities

1.6 Research Hypotheses

  1. The extracts of selected angiosperms and fungi have no significant anti-trypanosomal activities.
  2. The extracts of selected angiosperms and fungi are low in phytochemical content.
  • There are insignificant bioactive molecules in selected angiosperms and fungi.
  1. There are no significant differences in pack cell volume (PCV) of blood

before and after the therapeutic application of synthesized silver nano particle and non-synthesized extracts of angiosperms and fungi.

v.Thereare no silvernano particlessynthesized using selected angiosperms and fungiextracts.


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