Qualitative and Quantitative Phytochemical Screening of Bitter and Neem Leaves and their Potential as Antimicrobial Growth Promoter in Poultry Feed

Abstract
Gastrointestinal health challenges without in-feed antibiotics are a crucial concern to poultry farmers. Although, quite a few substitutes for antibiotics have emerged, phytogenics and antibiotic properties of medicinal plants cannot be overlooked with regard to control, good health and minimizing sub – clinical bacteria-induced infections by zoonotic enteropathogenic bacteria in poultry birds. Vernonia amygdalina (Bitter leaf) and Azadirachta indica (Neem) leaves were collected early in the morning and oven dried to 15% moisture content. The non-essential oil was obtained by cold maceration method using methanol. Appropriate methods were used for the qualitative and quantitative analysis of phytochemicals in the respective oils. Qualitative analysis of phytochemicals showed that, saponins and terpenoids were highly detected (+++) in V. amygdalina. Saponins and terpenoids were slightly detected (+) in A. indica. Phenolic compounds were highly detected (+++) in both plants. Flavonoids were also identified (++) in both plants, but tannins were highly detected (+++) in A. indica. Quantitative analysis revealed a rather high concentration of complete phenolic content and overall flavonoid content in V. amygdalina. Total phenolic content of 44.76 mg Gallic acid equivalent / g of extract and 57.21 mg Rutin equivalent / g of extract (total flavonoid content) was recorded in V. amygdalina and 25.77 mg Gallic acid equivalent / g of extract (total phenolic content) and 24.45 mg Rutin equivalent /g of extract (total flavonoid content) in A. indica. In conclusion, both plant extracts exhibited possibility as suitable substitutes to proprietary antibiotics that can be beneficial to gastrointestinal health and overall performance in animal nutrition.