Deep eutectic solvent-ultrasound assisted extraction as a green approach for enhanced extraction of naringenin from Searsia tripartita and retained their bioactivities

Abstract

Background: Naringenin (NA) is a natural flavonoid used in the formulation of a wide range of pharmaceutical, fragrance, and cosmetic products. In this research, NA was extracted from Searsia tripartita using an environmentally friendly, high efficiency extraction method: an ultrasound-assisted extraction with deep eutectic solvents (UAE-DES).

Methods: Six natural deep eutectic solvent systems were tested. Choline chloride was used as the hydrogen bond acceptor (HBA), and formic acid, ethylene glycol, lactic acid, urea, glycerol, and citric acid were used as hydrogen bond donors (HBD).

Results: Based on the results of single-factor experiments, response surface methodology using a Box-Behnken design was applied to determine the optimal conditions for UAE-DES. According to the results, the optimal NA extraction parameters were as follows: DES-1 consisted of choline chloride (HBA) and formic acid (HBD) in a mole ratio of 2:1, an extraction time of 10 min, an extraction temperature of 50°C, an ultrasonic amplitude of 75 W, and a solid-liquid ratio of 1/60 g/mL. Extracted NA was shown to inhibit the activity of different enzymes in vitro, including α-amylase, acetylcholinesterase, butyrylcholinesterase, tyrosinase, elastase, collagenase, and hyaluronidase.

Conclusion: Thus, the UAE-DES technique produced high-efficiency NA extraction while retaining bioactivity, implying broad application potential, and making it worthy of consideration as a high-throughput green extraction method.

Keywords: Searsia tripartita; anticholinesterase activity; green extraction; naringenin; natural deep eutectic solvent; response surface methodology; skin aging; ultrasonic-assisted extraction.

Figure 1

Impact of various extraction variables on NA extraction efficiency. (A) DES types, (B) DSE-1 molar ratio, (C) water content in DES-1, (D) extracting temperature, (E) ultrasonic power, (F) ultrasonic duration (G), and solid–liquid ratio. The data are reported as means ± SD (n = 3). A significant difference (p < 0.05) is indicated by data with different letters (A–D).

Figure 2

(A–D) Response surface for NA DES-UAE from ST as a function of the temperature and duration of ultrasound (A); the power and duration of ultrasound (B); the power and temperature of ultrasound (C); and the water content in DES-1 and the temperature of ultrasound (D).

Figure 3

Antioxidant and enzyme-inhibiting abilities of ST samples. Trolox equivalents per gram (mgTE/g) were used to represent DPPH and FRAP (A,B). The inhibitory capabilities of acetylcholinesterase (AchE) and butyrylcholinesterase (BchE) were represented in milligrams of galantamine equivalent per gram (mg GALAE/g) (C,D). The amount of acarbose equivalent per gram of sample (mmol ACE/g extract) was used to indicate the inhibitory ability of α-amylase (E). Tyrosinase inhibition is shown as mg KAE/g extract, meaning milligrams of kojic acid equivalent per gram of sample (F). Collagenase (G), elastase (H), and hyaluronidase (I) inhibition capacities are shown as percentages (%). The data are shown as mean SD (n = 3). Data with different letters indicate significant differences (p < 0.05) (A–I).