Employing Bifunctional Enzymes for Enhanced Extraction of Bioactives from Plants: Flavonoids as an Example

Abstract

A cost-effective and environmentally friendly approach was developed to improve the extraction of active ingredients from plants, in which a bifunctional enzyme was employed for not only facilitating cell wall degradation but also increasing the bioactivity of target compounds in the extract. In the aqueous extraction of flavonoids from Glycyrrhizae radix, Trichoderma viride cellulase, a commercial cell-wall-degrading enzyme, was found to efficiently deglycosylate liquiritin and isoliquiritin, which are of high content but low bioactivity, into their aglycones that have much higher physiological activities for dietary and medicinal uses. Under optimized conditions, the extraction yield of liquiritigenin and isoliquiritigenin aglycones reached 4.23 and 0.39 mg/g of dry weight (dw) with 6.51- and 3.55-fold increases, respectively. The same approach was expanded to the extraction of flavonoids from Scutellariae radix using Penicillium decumbens naringinase, where enhanced production of more bioactive bacalein and wogonin was achieved via enzymatic deglycosylation of bacalin and wogonoside.

Conventional and Emerging Extraction Processes of Flavonoids

“…Flavonoids are a type of polyphenolic compound, its chemical structure is varied but the general skeleton structure is composed of 15 carbones (C6-C3-C6), which are grouped in two aromatic rings (A and B) connected by a 3-carbon bridge that gives rise to an oxygenated heterocycle (C) [11][12][13][14][15] ( Figure 1). Flavonoids are derivatives of 1, 3-diphenylpropan-1-one and their biosynthetic pathway is the condensation of three malonyl-CoA molecules with one p-coumaroyl-CoA molecule to the intermediate chalcone [16,17].…”

The King of Chinese Medicine——Glycyrrhiza glabra (Licorice): All-round Inquiry in its Chemical Composition, Pharmacodynamics, Traditional and Medicinal Value

“…Licorice mainly contains saponins, flavonoids, and polysaccharides; glycyrrhizic acid, glycyrrhetinic acid, and other saponins; liquiritigenin and liquiritin and other flavonoids as the main active ingredients, which are mainly extracted by solvent extraction, ultrasound-assisted extraction, supercritical carbon dioxide extraction, microwave-assisted extraction, enzyme-assisted extraction, and other methods [25,29,30] . The more widely used is the solvent extraction method, which is based on the principle of “similar solubility.” The selection of appropriate solvents, such as ethanol, methanol, acetone, water, and other polar organic solvents induce leaching of chemical components from the raw material.…”