Nutritional Evaluation and In-vitro Free Radical Scavenging Activity of Pontederia Crassipes Aqueous Leaf Extract from Amassoma River Ecosystem

Abstract

Pontederia crassipes Mart., commonly known as water hyacinth, is a free-floating, invasive, perennial aquatic plant widely distributed in freshwater ecosystems across tropical and subtropical regions. It has gained scientific attention for its rich phytochemical profile and potential applications. This study evaluated the nutritional and radical scavenging activity of the plant P. crassipes. The methods applied to analyze the plants are Gas Chromatography-Mass Spectroscopy (GC-MS) for bioactive compounds, Flame Atomic Absorption Spectroscopy (FAAS) for mineral composition, High-Performance Liquid Chromatography (HPLC) for amino acids and Spectrophotometric methods for antioxidant assays. The GC-MS analysis revealed the presence of various bioactive compounds. The proximate composition of carbohydrate was 39.09 %.  Seventeen amino acids, including essential and non-essential types, were identified. Isoleucine exhibited the highest concentration (29.11 µmol/L), and methionine (0.79 µmol/L) exhibited the lowest. The minerals analysed in the leaf extract of P. crassipes showed that it contains micro- and macro-nutrients. They include Iron (Fe), Magnesium (Mg), Manganese (Mn), Selenium (Se), Zinc (Zn), Calcium (Ca), Sodium (Na), Potassium (K), and   Copper (Cu). The values from the results obtained are presented following the highest concentration to the lowest concentration order, Ca= 9.234±0.107 mg/L, to be the highest and Se=0.082± 0.001 mg/L. The plant is rich in both macronutrients and micronutrients. The antioxidant properties analysed were   DPPH, ABTS, Hydroxyl radical, Nitric Oxide, FRAP, PAP and RPA. The plant shows significant antioxidant properties when compared to standards. The results from DPPH at the highest concentrations of 100 mg/ml was 95.50%, and at the lowest, 10mg/ml is 78.52%, ABTS at 300 mg/ml is 78.82% and at 100 mg/ml is 70.25%. Hydroxyl radical at 80 mg/ml is 62.23% and at 10 mg/ml is 57.88%, Nitric Oxide at 80 mg/ml has 0.1715%, FRAP at 80 mg/ml is 40.29% and at 10 mgml is at 17.38%, PAP at 80 mg/ml is 0.111% and at 10mg/ml is at 0.084% and RPA at 80 mg/ml is 42.73% while at 10 mg/ml it is 39.37%.  Hence, P. crassipes can serve as a supplementary source of amino acids, minerals and antioxidant compounds.