GC–MS Analysis and Antimalarial Activity of Methanolic Leaf Extract of Carica papaya against Plasmodium berghei NK65 Infection in Swiss Mice

Abstract

Aim: The study determines the GC-MS and the anti-malarial activity of methanolic leaf extract of Carica papaya in Swiss mice infected with Plasmodium berghei NK65.
 Study Design: The experimental study lasted for five weeks.
 Place of Study: Department of Chemical Sciences (Biochemistry Unit) and animal House unit in Department of Biological Sciences (Environmental Biology Unit), School of Pure and Applied Sciences, Lagos State Polytechnic, Ikorodu, Lagos, Nigeria.
 Study Design and Methodology: AAS, GC-MS and phytochemical analyses were determined in the plant extract using standard procedures. Thirty-six Swiss mice of both sexes (26–32g) were divided into six groups of six mice each. Group A (normal control) was untreated and uninfected. Groups B–F were intraperitoneally inoculated with P. berghei NK65, while group B (disease control) was untreated-infected group, group C and D (standard drugs) received standard drugs, chloroquine (10 mg/kg B.WT) and artesunate (10 mg/kg B.WT); groups E and F received methanolic leaf extract of C. papaya at 400 and 600 mg/kg B.WT respectively. WBC, HCT and HGB were determined in the whole blood using BC-3200 Auto Hematology Analyzer. MDA, TP, SOD % inhibition, SOD unit, CAT and GSH were all determined in the liver homogenate using standard procedures.
 Results: The AAS analysis shows that the extract contains minerals like: potassium, calcium, magnesium, iron and sodium. Twenty-six compounds were identified to be present in the extract using GC-MS analysis. The active compounds with their retention time, molecular weight, molecular formula, peak area and activities were predicted. The three major prevailing compounds and their percentage abundance are: squalene (27.28%), neophytadiene (12.71%) and phytol (10.16%) respectively. The phytochemical analysis indicates the presence of tannins, saponins, alkaloids, phenolic compounds etc. The C. papaya extract caused 56.76% and 75.53% significant (P<0.05) reduction in parasitemia at 400 and 600 mg/kg body weight respectively while chloroquine exerted 92.86% and artesunate exerted 90.67% reduction at 10 mg/kg body weight respectively carried out during curative test. The extract significantly (P<0.05) reduced WBC count and increase HGB and HCT concentration in the treated mice compared to the infected untreated mice. There were significant (p<0.05) increase in the TP, SOD % inhibition, SOD unit, GSH and CAT levels in the liver homogenate of animals treated with chloroquine, artesunate and extract of C. papaya compared to the untreated mice. MDA level was significantly decreased in the malaria treated mice compared to the untreated mice.
 Conclusions: The study shows that methanolic leaf extract of Carica papaya possess antimalarial activity in Swiss mice infected with Plasmodium berghei NK 65.