Proximate Composition, Mineral Content and Phytochemical Evaluation of Different Solvent Extracts of Pineapple (Ananas comosus) Stalk

Abstract

The objective of this study was to evaluate the proximate composition, mineral content and phytochemical constituents of Ananas comosus stalks using distilled water, methanol, ethanol, chloroform and petroleum ether as extraction solvents. Analysis of minerals present in the different extracts of the stalk of A. comosus revealed that the aqueous extract had the highest concentration of sodium, magnesium, zinc, tin, molybdenum and manganese while the lowest was found in petroleum ether extract. Methanol extract had the highest concentration of potassium, iron and copper. The result of the physicochemical analysis of the stalk of A. comosus revealed that the stalk was high in nitrogen free extract (58.74±1.13 %). However, ether extract had the least value (1.12±0.20 %). Qualitative phytochemical screening of A. comosus stalk extract revealed the presence of saponins, alkaloid and terpenes. Quantitative evaluation of the phytoconstituents revealed that flavonoids and phenol were highest in petroleum ether extracts (2.74±0.02 mg/kg and 2.73±0.02 mg/kg) while alkaloids concentration was highest in the ethanol extract (1.78±0.01 mg/ml). The study found that Ananas comosus stalk extracts had a good amount of micronutrients according to the various criteria examined; the high ash content also supports this finding. The study showed that the stalk of A. comosus is a good source of important phytochemicals.

Keywords

• Mineral content;
• phytoconstituents;
• micronutrients;
• pineapple stalk