Abstract:
Leishmaniasis is classified by the WHO as an emergent category of one of the
uncontrolled and NTDsco-exist with malnutrition and HIV/AIDS. Due to lack of
vaccine, control relies on ineffective, toxic and expensive chemotherapy and vector
control, which are not sustainable. The study was aimed at determination of efficacy
and safety, nutritional and antioxidant activity of Kenyan A. muricata (L.) and A.
squamosa (L.) fruits extracts in BALB/c mice model of L. majorleishmaniasis to
develope supportive therapy and efficacious and safe antilrishmanicidal agents. Ripe
fresh fruitswere collected from farms in Kilifi and Kwale Counties, Coast regionof
Kenya. Dried fruits were powdered, subjected to extraction with solvents of
increasing polarity (Hexane, Ethyl Acetate, Methanol and Water) for 48 hours.
Proximate and nutritional composition of various partsof the plants, phytochemicals
screening, carotenoidsanalysis, in vitroand in vivo cytotoxicity, antioxidant, DNAbinding and DNA Topo I inhibitory activities of the extracts wereassesed. The
efficacies of thedifferent extracts against L. major parasites (IDUB/KE/83=NLB-144
strain) wasassessed in vitro in inbred infected BALB/c mice maintained on AFPP and
RP and in vitro using promastigotes. The results were expressed as mean analyzed
using mean separation done through Fischer least significance difference by GenStat
program. Comparisons between two treatments were done by Student’s t-test and
significance established by ANOVA. Differences of P<0.05 were considered
statistically significant.Majority of the phytochemicalswere detected inthe
extracts.The fruitdemonstrated high dry matter, moisture content, crude fat, crude
protein, crude fibre, total carbohydrates, oil content, reducing sugar, TSS, ascorbic
acid, tocopherol, titratable acidity and ash content. Fatty acid profile showed
presence of SFA, MUFAand PUFA. Different parts revealed varying amounts of P,
Na, Ca, Mg and P whereas Cu, Fe, Zn and Se were detected in trace amounts. The
HPLC profilingof carotinoids revealed presence of neoxanthin, violaxanthin and
zeaxanthin, α-carotene, β-carotene, γ-caroteneand chlorophyll. The extracts showed
in vitro and in vivoantioxidant activitiesagainst non-enzymatic and enzymatic
antioxidants. The BALB/c mice fed with AFPP showed improve growth, metabolic
efficiency and feed utilization.The extracts showed a dose dependent in vitro
antileishmanial activity with MIC values ranged between 12.50±1.03 μg/mL to
55.0±2.97 μg/mL. The extracts showed antileishmanial activity in vivo through
reduction ofLHFD swelling and lesion sizes. The extracts ranged from highly toxic
(IC50 2.54±0.44-7.55±1.19µg/mL), toxic (IC50 12.85±2.80-94.07±5.81µg/mL) and
moderately toxic (IC50 104.81±1.16-292.94±10.10µg/mL). No mortality was
observed even at highest dose of 2500 mg/Kg suggesting LD50>2500mg/Kg. The
extractsshowed DNA binding interaction via displacement of methyl green in DNA
methyl green test and DNA Topo I inhibitory activity by inhibiting relaxation of
supercoiled DNA pBR322 at 5, 25 and 100 µM. It can be concluded that the
nutritional components of the fruits were responsible for the improve growth,
metabolic efficiency and feed utilization of BALB/c mice fed with AFFP.
Thephytochemicals detected were responsible for the in vitro and in vivo antioxidant
and antileishmanial activities besides DNA binding interaction and DNA Topo I
invibitory activity. Low IC50 and lack of mortality in extracts treated mice suggests
safety. The study recommends further investigation using purified fractionsof these
extracts on higher animal model of the lishmaniasis.