Polysaccharides in Selenium-Enriched Tea: Extraction Performance under Innovative Technologies and Antioxidant...

Area of Science:

• Food Science and Technology
• Biochemistry
• Extraction Technology

Background:

• Selenium-enriched tea polysaccharides (Se-TPSs) possess valuable biological activities.
• Efficient extraction of Se-TPSs under mild conditions is crucial for preserving their integrity and bioactivity.
• Conventional extraction methods may require harsh conditions, potentially degrading polysaccharides.

Purpose of the Study:

• To investigate the efficacy of pulsed electric fields (PEF) and ultrasonic-assisted extraction (UE) for Se-TPS extraction.
• To compare combined PEF and UE methods with conventional extraction (CE).
• To evaluate the impact of these methods on Se-TPS yield, structural stability, selenium content, and antioxidant activity.

Main Methods:

• Extraction of Se-TPSs using two combined processes: PEF followed by CE, and PEF followed by UE.
• Characterization of Se-TPSs using Gel Permeation Chromatography (GPC), UV-Vis spectroscopy, and Fourier-Transform Infrared (FT-IR) spectroscopy.
• Assessment of antioxidant activities through in vitro assays (hydroxyl radical, superoxide anion radical, ABTS+ radical scavenging, and total antioxidant capacity).

Main Results:

• Combined PEF+CE and PEF+UE methods significantly improved extraction yields compared to conventional methods.
• PEF treatment increased selenium content in Se-TPSs by 160.14% due to lower extraction temperatures.
• Se-TPSs extracted using PEF-assisted methods maintained structural stability and exhibited significant in vitro antioxidant activities, with PEF+CE showing particularly high efficacy.

Conclusions:

• PEF and UE are effective non-thermal technologies for enhancing Se-TPS extraction under mild conditions.
• The PEF+CE method demonstrated superior performance in terms of yield and antioxidant activity, likely due to a synergistic effect between selenium and polysaccharides.
• These findings support the application of PEF-assisted extraction for the production of selenium-enriched tea functional ingredients for the food industry.