Optimization of Enzyme-Assisted Extraction of Flavonoids from Corn Husks

Abstract

Corn husks are an important byproduct of the corn processing industry. Although they are a rich source of bioactive compounds, especially flavonoids, corn husks are usually disposed of or used as animal feed. In this paper, we investigate their recovery by an enzyme-assisted extraction process consisting of a pretreatment of the plant material with cellulase followed by solvent extraction with aqueous ethanol. A four-factor, three-level Box–Behnken design combined with the response surface methodology was used to optimize the enzyme dosage (0.3–0.5 g/100 g), incubation time (1.5–2.5 h), liquid-to-solid ratio (30–40 mL g−1) and ethanol concentration in the solvent (60–80% v/v). Under the optimal conditions, about 1.3 g of total flavonoids per 100 g of dry waste were recovered. A statistical analysis of the results was performed to provide a quantitative estimation of the influence of the four factors, alone or in combination, on the extraction yields. Overall, the results from this study indicate that corn husks are a valuable source of flavonoids and that they can be easily recovered by a sustainable and environmentally friendly extraction process.

Optimization of aqueous enzyme‐assisted extraction of rosmarinic acid from rosemary ( Rosmarinus officinalis L.) leaves and the antioxidant activity of the extract

“…At any extraction time, the RA content drastically enhanced and reached the highest level with the increase in enzyme concentration, which could be attributed to the hydrolyzation of the components of plant cell wall and membrane by the enzyme (Jiang et al, 2010); therefore, a high concentration of enzymes increased the efficiency of plant cell degradation. This result corresponded with that of cellulase-assisted extraction of essential oil from C. camphora (Yu et al, 2019) and flavonoid extraction from corn husks (Zuorro et al, 2019). essential oil from C. camphora (Yu et al, 2019), and protease-assisted oil extraction from insects (Su et al, 2019).…”

“…Combined influences of the extraction time and water-to-sample ratio on the RA content at a constant enzyme concentration (2 hr) and extraction temperature (40°C) F I G U R E 2 Combined influences of the extraction time and enzyme concentration on the RA content at a constant temperature (40°C) and water-to-sample ratio (30 ml/g) camphora (Yu et al, 2019) and flavonoid extraction from corn husks (Zuorro et al, 2019). Similar to the extraction time, the enzyme concentration had a significant influence on the RA extraction.…”

Optimization of pretreating poplar wood shavings with cellulase to produce binderless fiberboard using response surface methodology

“…The 3D response surfaces and 2D contour plots could also locate the optimum values of the factors for the maximum of the response. The maximum predicted response was indicated by the surface confined in the smallest ellipse in the contour diagram (Muralidhar et al 2001;He et al 2013;Zuorro et al 2019). Peaks were found in 3D response surfaces (Fig.…”

Antioxidant Molecules from Plant Waste: Extraction Techniques and Biological Properties

“…Enzyme-assisted extraction has been used to extract various compounds from vegetable waste, such as carotenoids and flavonoids, among others [114][115][116][117]. However, in recent times, enzymatic technology is a trending biotechnological tool to obtain bioactive peptides from plant origin waste; in fact, bioactive peptides have received much attention because of their interesting functional and bioactive properties; and can be used as nutraceuticals for the development of functional foods [38,118].…”