Preliminary Phytochemical Screening and Antiviral Potential of Methanol Stem Bark Extract of Enantia chlorantha Oliver (Annonaceae) and Boswellia dalzielii Hutch (Burseraceae) against Newcastle Disease In Ovo

Abstract

Aim of the Study: To determine the phytochemicals and the antiviral activity of methanol stem bark extract of Enantia chlorantha and Boswellia dalzielii against Newcastle disease virus in embryonated eggs. Materials and Methods: Preliminary phytochemical screening was carried out using standard methods. Investigation on the effect of stem bark of Enantia chlorantha and Boswellia dalzielii methanol  extracts against Newcastle disease (ND) virus was carried out using an in ovo assay. Nine–day-old embryonated chicken eggs were used. 0.2ml New Castle Disease virus (NDV) pre-treated with methanol extract of Enantia chlorantha Oliver and Boswellia dalzielii Hutch (Stem bark) at final concentrations of 150, 100, 50, 25, 12.5 mg/ml were administered. Controls were included, embryos were observed daily for survival. Allantoic fluids from treated eggs were collected for spot test and haemagglutination test to detect NDV in the eggs. Results: Phytochemical analysis carried out on Enantia chlorantha Oliv. (stem bark),  revealed the presence of alkaloids, reducing sugars, cardiac glycosides,  steroid, triterpenes and glycosides, while tannin and flavonoids were found to be absent. Boswellia dalzielii Hutch revealed the presence of carbohydrates, steroids, triterpenes, cardiac glycosides, tannins and flavonoids and absence of alkaloid.The result of the antiviral assay showed that the minimum toxic concentration of both extracts is 150 mg/ml. Boswellia dalzielii showed the most significant activity against NDV with complete survival of the embryo at all concentration studied and complete clearance of the virus from the allantoic fluid, as compared to Enantia chlorantha where mortalities were seen at 150 and 25 mg/ml respectively. Conclusion: This finding has clearly demonstrated that Enantia chlorantha and Boswellia dalzielii stem bark extract has antiviral potential against NDV in ovo.