T/ZMX 004-2020 Determination of total flavonoids in Zhangjiajie berberry tea

Scope

Scope: This document specifies the principles, instruments and equipment, reagents and solutions, and methods of operation and calculation of total flavonoids in Zhangjiajie berry tea. This document is applicable to the determination of total flavonoids in berry tea produced by members of the Zhangjiajie Berry Tea Association; Main technical content: 3. Terms and definitions The following terms and definitions are applicable to this document. 3.1 Zhangjiajie berry tea Specifically refers to the Amelopsis grossedentata plants grown and cultivated in the administrative area of Zhangjiajie City, with their young stems and leaves or mature green leaves used as raw materials. It is processed through methods such as spreading, greening, kneading, crystallization, and drying to produce a substitute tea beverage. 3.2 Total flavonoids It refers to a group of flavonoid compounds with a benzopyran ring structure, widely found in the plant kingdom. The most common ones are flavones and flavanols, including dihydroquercetin, isoflavones, dihydroflavones, flavanols, chalcones, orange ketones, anthocyanins, and new flavonoids. The main active ingredient in Amelopsis grossedentata leaves is dihydroquercetin, with a maximum UV absorption wavelength of 291 nm. By creating a standard working curve and measuring the absorbance of the sample, the total flavonoid content in the sample can be calculated. 5. Instruments and equipment 5.1 Instruments UV-Vis spectrophotometer (wavelength range 190nm–900nm, Shimadzu Corporation, Japan), balance (accuracy 0.001g, Mettler-Toledo Instruments Shanghai Co., Ltd.), water bath (Shanghai Jinghong Laboratory Equipment Co., Ltd.), crusher (Zhejiang Yiligong Trading Co., Ltd.). 5.2 Utensils Volumetric flasks (10mL, 25mL, 50mL, and 100mL), 10mm cuvettes. 6. Reagents and solutions 6.1 Unless otherwise specified, all reagents used in this document are of analytical grade (AR), and the water is distilled water. 6.2 5% AlCl3 solut

Development Information

Related Standards