Optimization of Ultrasonic-Assisted Enzymatic Extraction Conditions for Improving Total Phenolic Content, Antioxidant and Antitumor Activities In Vitro from Trapa quadrispinosa Roxb. Residues

Abstract

Stems are the important residues of Trapa quadrispinosa Roxb., which are abundant in phenolic compounds. Ultrasonic-assisted enzymatic extraction (UAEE) is confirmed as a novel extraction technology with main advantages of enhancing extraction yield and physiological activities of the extracts from various plants. In this study, UAEE was applied to obtain the highest yield of phenolic content, strongest antioxidant, and antitumor activities and to optimize the extraction conditions using response surface methodology (RSM). The extracts from the stems of T. quadrispinosa were characterized by determination of their antioxidant activities through 2,2-azinobis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS), 1,1-Diphenyl-2-picrylhydrazxyl (DPPH) radical scavenging, total antioxidant capacity (TAC), ferric reducing antioxidant capacity (FRAC) methods and of their antitumor activity by MTT method. The selected key independent variables were cellulase concentration (X1: 1.5%–2.5%), extraction time (X2: 20–30 min) and extraction temperature (X3: 40–60 °C). The optimal extraction conditions for total phenolic content (TPC) value of the extracts were determined as 1.74% cellulase concentration, 25.5 min ultrasonic extraction time and 49.0 °C ultrasonic temperature. Under these conditions, the highest TPC value of 53.6 ± 2.2 mg Gallic acid equivalent (GAE)/g dry weight (DW) was obtained, which agreed well with the predicted value (52.596 mg GAE/g·DW. Furthermore, the extracts obtained from UAEE presented highest antioxidant activities through ABTS, DPPH, TAC and FRAC methods were of 1.54 ± 0.09 mmol Trolox equivalent (TE)/g·DW; 1.45 ± 0.07 mmol·TE/g·DW; 45.2 ± 2.2 mg·GAE/g·DW; 50.4 ± 2.6 μmol FeSO4 equivalent/g·DW and lowest IC50 values of 160.4 ± 11.6 μg/mL, 126.1 ± 10.8 μg/mL, and 178.3 ± 13.1 μg/mL against Hela, HepG-2 and U251 tumor cells, respectively. The results indicated that the UAEE was an efficient alternative to improve extraction yield and enhance the antioxidant and antitumor activities of the extracts. The phenolic extracts from the stems of T. quadrispinosa had significant antioxidant and antitumor activities, which could be used as a source of potential antioxidant and antitumor agents.

Optimization of Ultrasound-Assisted Extraction of Flavonoids from Celastrus hindsii Leaves Using Response Surface Methodology and Evaluation of Their Antioxidant and Antitumor Activities

“…Basically, extraction is the first step in the isolation process to obtain bioactive compounds from biomass materials with its purpose to maximize the content of target compounds for their further utilization. To obtain flavonoids from plant materials, several methods have been applied to enhance extraction efficiency [15,16]. Studies have shown that not only the extraction yield but also the extraction technique is affected by the extracting solvent [17,18].…”

“…ose methods are timeconsuming, have low extraction efficiency, and result in the loss of bioactivities of the flavonoids due to high extraction temperature [19]. To address these problems, microwaveassisted extraction [15] and supercritical fluid extraction [20] have been developed for the extraction of flavonoids [15]. Although those methods efficiently extract flavonoids from plant materials, the microwave-assisted extraction is difficult to scale up and requires high microwave power, which increases energy consumption [15,21], whereas the supercritical method proceeds at high pressure (48 MPa), which requires expensive reactor and rises a safety concern [20].…”

“…To address these problems, microwaveassisted extraction [15] and supercritical fluid extraction [20] have been developed for the extraction of flavonoids [15]. Although those methods efficiently extract flavonoids from plant materials, the microwave-assisted extraction is difficult to scale up and requires high microwave power, which increases energy consumption [15,21], whereas the supercritical method proceeds at high pressure (48 MPa), which requires expensive reactor and rises a safety concern [20]. Enzyme-assisted extraction has been proposed as another alternative for the flavonoids extraction because this process was performed at mild extraction conditions [22,23].…”

Optimization of a Novel Kinetic-Assisted Infundation for Rich-Egcg and Polyphenols of White Tea (Camellia Sinensis) Using Central Composite Design

“…Temperature and stirring speed can affect extraction time [13,18,19,22]. Temperature dramatically influences solubility of solutes, diffusion coefficients and dielectric water constants [15,19,23]. So the KAI technique determines the stirring rate and the extraction time be included in the optimization variable.…”

“…The standard used for the determination of TPC is gallic acid [15][16][17]. Determination of TPC uses the folin-ciocalteu reagent with the formation of a stable blue color as an important indicator in the reaction.…”