Recovering Bioactive Compounds from Other Agricultural Wastes

The recovery of bioactive compounds is commonly accomplished by a unit operation known as extraction. Edaphoclimatic aspects, morphology, the location of the solute in the matrix, shape, size, porosity and part of the plant used are some of the raw material characteristics that affect the extraction process, because they have direct effects on the mass transfer rate. The supercritical fluid extraction (SFE) process can be more effective than conventional techniques in selectively recovering bioactive compounds from wastes and reducing extraction times. As for pepper waste, conventional extraction of bioactive compounds from onion waste commonly uses a solvent at room pressure. Microwave-assisted extraction (MAE) is a suitable process for the rapid recovery of compounds from cotton waste, yielding an extract with favourable physical properties and oxidative stability. Pepper, onion and cotton wastes can be used for the recovery of flavonoids, capsaicinoids, terpenes, terpenoids, tocopherols, carotenoids, polyphenols and phytosterols.