Fast screening of sweet tea antioxidants and new green and precise extraction technology

　　Recently, the China Urban Agriculture Research Institute of Agricultural Sciences, Chengdu University, the American University of Central Florida, Zhongshan University and Sichuan Academy of Chinese natural resources - New Zealand "all the way along the" kiwi joint experimental research staff room, in the internationally renowned journal "Food bioscience" ( An experimental article titled "Screening and process optimization of ultrasound-assisted extraction of main antioxidants from sweet tea (Lithocarpus litseifolius [Hance] Chun)" was published on JCR Zone II, Impact Factor 4.
24), detailing the use of DPPH-Spiking HPLC A new method for screening antioxidants in sweet tea extracts , combined with ultrasonic assisted extraction (UAE) to accurately extract the antioxidants from the screening
.
Compared with conventional extraction methods, this method can achieve green and precise extraction of natural antioxidants, and has strong promotion and application value
.
The Institute of Urban Agriculture of the Chinese Academy of Agricultural Sciences is the first communication unit.
Dr.
Gan Renyou, the chief scientist of the Plant and Human Health Mechanism Innovation Team, and Dr.
Zhuang Qiguo from the China-New Zealand “Belt and Road” Kiwi Joint Laboratory of the Sichuan Academy of Natural Resources Sciences are the co-corresponding authors of this article, Plant The first author is Liu Yi, the research assistant of the Human Health Mechanism Innovation Team
.
This work was supported by the Basic Research Fund of the Central Public Welfare Scientific Research Institution (No.
Y2020XK05) and the Local Financial Project of the National Agricultural Science and Technology Center (No.
NASC2020KR02)
.

 

　　Article overview

 

　　As a kind of herbal tea that has been drunk for a long time, sweet tea is rich in a variety of flavonoids, such as 2',6'-dihydroxy-4'-methoxy-dihydrochalcone, trilobatin, phloretin, phlorizin isoquercitrin and the like
.
Sweet tea has a variety of health effects, such as anti-inflammatory and anti-cancer effects, which are believed to be closely related to the antioxidant capacity of its antioxidants
.
However, the main antioxidants in sweet tea are still unclear
.
Traditional methods of screening and extracting natural antioxidants are time-consuming and expensive
.
Recently, the DPPH-spiking HPLC method has successfully replaced the traditional rapid identification method of natural antioxidants, and ultrasonic assisted extraction, as a green extraction method, is a good alternative to traditional extraction methods and has been widely used in the extraction of natural plant products.

.
Therefore, the DPPH-spiking HPLC method combined with the ultrasonic assisted extraction method (UAE) can realize the rapid screening and identification of antioxidants and the green and precise extraction
.
In this study, the DPPH-spiking HPLC method combined with the optimized ultrasonic assisted extraction method (UAE) was used to screen and extract the antioxidants in sweet tea
.
This new method can identify and extract the main antioxidants in sweet tea, and provide a reference for discovering and extracting more new natural antioxidants in the future
.

 

　　Conclusion and Outlook

 

　　In this work, the DPPH-spiking HPLC method was used to screen out the main antioxidants from sweet tea: isoquercitrin, phloridzin and trilobatin (Figure 1)
.
The ability of these three antioxidants to scavenge DPPH free radicals is as follows: isoquercitrin>trilobin>phloridin, and their antioxidant capacity is mainly related to the number and position of -OH groups
.
Under the optimal UAE conditions, the yields of isoquercitrin, phloridin and trilobatin were 17.
1±1.
26, 34.
8±1.
49 and 163±1.
73 mg/g, respectively.
The antioxidant capacity of the three main antioxidants accounted for the total 61.
09% of antioxidant capacity (Figure 2)
.
Compared with microwave assisted extraction (MAE) and macerating extraction (ME), UAE is a more suitable method for extracting antioxidants from sweet tea
.
This research provides theoretical guidance for the discovery and precise extraction of potential antioxidants in sweet tea.
These sweet tea antioxidants can be used as a good dietary antioxidant for the development of functional foods and health products
.

　　Figure 1 Screening of antioxidants

　　Figure 2 Ultrasound-assisted extraction optimization

 

　　references:

 

　　Liu, Y.
, Liu, HY, Xia, Y.
, Guo, H.
, He, XQ, Li, H.
, Wu, DT, Geng, F.
, Lin, FJ, Li, H.
Bin, Zhuang, QG ,& Gan, RY (2021)
.
Screening and process optimization of ultrasound-assisted extraction of main antioxidants from sweet tea (Lithocarpus litseifolius [Hance] Chun)
.
Food Bioscience, 43, 101277

 

　　Full text link: https://doi.
org/10.
1016/j.
fbio.
2021.
101277