Prelusive scale extraction of mangiferin from Mangifera indica leaves: Assessing solvent competency, process optimization, kinetic study and diffusion modelling

Abstract

An analysis of extraction method using different solvents for efficient obtention of bioactive compounds from plant sources is very important because there is a large demand for these compounds in the food, pharmaceutical and other allied industries. Mangiferin, a phenolic compound, present in large proportion in mango leaves and is endow to have exceptional antioxidant property apart from demonstrating remarkable prospective demand in nutraceutical, cosmetic and food industries. In the present investigation, the extraction by solvent modus operandi was followed to extract the mangiferin compound from mango leaves. The effect of solvent type, age of leaf, time of extraction (1–6 h) and extraction temperature (40–70 °C) on the recovery of mangiferin were investigated. It was inferred that the yield of mangiferin from young leaves and old leaves were 22.28% and 10.74% respectively at the optimum condition. The extraction efficiency of four solvents ethanol, acetone, ethyl acetate and hexane were evaluated. The extraction method using ethanol as solvent was considered to be productive because significant quantity of desired compound was obtained. This can be attributed to the polar characteristic of the extracting agent. The optimized extraction time, temperature and sample mass to solvent volume ratio for maximum mangiferin extraction were found to be 6 h, 70 °C and 1:15 respectively. The rate of extraction was analyzed using first and second order kinetic model and the parameters were evaluated using linear regression technique. The extraction process rate constant and temperature were linearly related with an activation energy factor 20.25 kJ/mol. Thermodynamic factors which include activation enthalpy (ΔH*) and activation Gibb’s free energy (ΔG*) were evaluated and it was concluded that the process is endothermic and non-spontaneous in identity. The intra particle diffusion coefficient was estimated using Wilke Chang model. The result concluded that the diffusion coefficient of active component is directly proportional to temperature. The applicability of Peleg model and logarithmic model to narrate the kinetics of the solid-liquid extraction process were tested. Based on the significance of the statistical parameters, it can be ascertained that Peleg model has a fine agreement with the experimental values. The regression coefficient was found to be high in Peleg model (R2 = 0.9923) with least Root Mean Squared Deviation RMSD value of 0.0135 confirms the applicability of this model.