Continuous or Batch Solid-Liquid Extraction of Antioxidant Compounds from Seeds of Sterculia apetala Plant and Kinetic Release Study

Abstract

This work has been intended to investigate the antioxidant properties of compounds extracted from seeds of Sterculia apetala (a plant from Central America) in order to add further results to the relatively poor existing literature on the beneficial properties of this plant. Different extraction methodologies were used such as batch or continuous extraction conditions using water or ethanol 50% as solvents. The kinetic study has allowed estimation of the effective diffusion coefficients in a continuous solid-liquid extraction, highlighting the strict dependence of the diffusion rate and temperature and kind of solvent, showing the highest diffusion rate with ethanol 50% at 60 °C. The comparison between different techniques and two solvents led to the selection of water as the best extraction solvent while batch mechanically-agitated extraction was the most efficient mode, with the benefits of use of an environmental-friendly solvent and reduction in process time to achieve a high amount of extracted phenolic compounds. The analysis techniques used were ABTS and Folin-Ciocalteau methods to investigate the antioxidant activity and quantify the Total Phenolic Content (TPC) respectively. Also, different fatty acids were extracted from Sterculia apetala seeds and analysed by Gas Chromatography in order to quantify other interesting chemical species besides antioxidants.

Extraction Kinetics of Phenolic Antioxidants from the Hydro Distillation Residues of Rosemary and Effect of Pretreatment and Extraction Parameters

“…C 0 indicates a very rapid extraction at the initial contact between fresh solvent and sample [ 29 , 30 ]. It is evident that the initially extracted phenolic components by water, ethanol, or acetone are low, while almost a two-fold increase is observed with ethanol-water mixtures and even more with acetone-water.…”

Effects of Water Deficit Irrigation on Phenolic Composition and Antioxidant Activity of Monastrell Grapes under Semiarid Conditions

“…Total Phenolic Content was determined by the Folin-Ciocalteu method described by Mosca [ 30 ]. The grape extract samples (explained in Section 2.2 ) and reagents were pipetted into each well in a 96-well microplate in this order: sample (adequately diluted), Folin-reagent (0.62 M), sodium carbonate solution 4% ( w/w ), and ultrapure water (1:4:4:4).…”

Comparison of Maceration and Ultrasonication for Green Extraction of Phenolic Acids from Echinacea purpurea Aerial Parts

“…Maceration is the oldest of the solid-liquid extraction methods and is characterized by the simplicity and low cost of the procedure, as well as by the long duration needed for the achievement of an equilibrium concentration of the extracted metabolite in the solvent [25]. The use of glycerol for maceration of phenolic secondary metabolites is relatively rare [11,26].…”