Phenolic Profiling and In-Vitro Bioactivities of Corn (Zea mays L.) Tassel Extracts by Combining Enzyme-Assisted Extraction

Abstract

In this work, enzyme-assisted extraction (EAE) of phenolic compounds from corn tassel using cellulase, protease, and their combination (1:1) was developed and optimized by central composite response surface methodology. The phenolic profile of obtained corn tassel extracts (CTE) was elucidated by high-performance liquid chromatography–diode array detection (HPLC–DAD) analysis, and their antioxidative, antimicrobial, and cytotoxic properties were evaluated in vitro. The results showed that CTE by EAE with combined enzymes had the highest total phenolic content (TPC). Under optimum enzymatic conditions, the experimental TPC values were 9.78, 8.45, and 10.70 mg/g, respectively, which were significantly higher than that of the non-enzymatic control (6.75 mg/g) (p < 0.05). Fourteen more phenolic compounds (13.80–1694.36 µg/g) were identified in CTE by EAE with the combined enzymes, and thus the antioxidant activity of that extract, determined by DPPH and ABTS radical scavenging method, was demonstrated to be stronger than that of the extracts by EAE with the single and ethanol extraction. Furthermore, this extract also showed remarkably better antimicrobial properties against all tested food-borne pathogenic bacteria and mycotoxigenic fungi than CTE by other extraction methods. CTE by EAE were nontoxic to normal lung fibroblast cell line (Wi-38) but cytotoxic to human colorectal and lung cancer cell lines (Caco-2 and A549), with IC50 values of 392.62–461.98 and 210.66–359.56 µg/mL, respectively, which indicated its potential anticancer properties. In conclusion, CTE by EAE, especially with the combined use of cellulase and protease, seems to hold promising potential for multifunctional application in food and pharma fields.

Effect of Whey Protein Edible Coating Incorporated with Mango Peel Extract on Postharvest Quality, Bioactive Compounds and Shelf Life of Broccoli

“…100 µL of WPC and WPC-Mango peel extract coating solutions were seeded into the well and the plate was incubated at 37 • C for 24-48 h. The inhibition zone diameter around the wells was calculated in millimetres (mm) whereby, zone of inhibition (ZOI) = diameter of growth inhibited zone−diameter of the well. The absence of a zone of inhibition was considered to represent that there was no activity [26].…”

Research Progress on Extraction and Detection Technologies of Flavonoid Compounds in Foods

“…Due to the effect of temperature and pH on enzyme activity, the temperature for enzyme-assisted extraction of flavonoids is usually within 60 • C and the pH value is between 5 and 8. Elsayed et al [48] used cellulase, protease, and their combination (1:1) to extract phenolic compounds (EAE) from maize male ears and optimized them using the central composite response surface method. Under optimum enzymatic conditions, the experimental TPC values were 9.78, 8.45, and 10.70 mg/g, respectively, which were significantly higher than that of the non-enzymatic control (6.75 mg/g).…”

Functional biscuits enriched with potato peel powder: Physical, chemical, rheological, and antioxidants properties

“…In extracting total phenols, the method of L. Wada and B. Ou [32] was employed, and the total phenols were estimated using the Folin Ciocalteu method according to [33,34].…”