Objective To study the effects of deep eutectic solvent (DES) on the absorbance of tea polysaccharide by visible spectrophotometry, and establish a fast and efficient method for the determination of tea polysaccharide. Methods Choline chloride/DL-tartaric acid was used as the extraction solvent of tea polysaccharide. The influence of DES on the determination of tea polysaccharide content in anthrone sulfuric acid and phenol-sulfuric acid 2 kinds of detection methods was investigated. The linear relationship, precision, stability, repeatability and standard recovery rate of the 2 kinds of detection methods were compared. Results The best method for the determination of tea polysaccharides was phenol-sulfuric acid method, the optimal detection wavelength was 484 nm, and the absorbance had a good linear relationship with glucose concentration between 20 and 100 μg/mL. The precision relative standard deviation (RSD) of this method was 0.10%, the stability RSD was 0.00%, the repeatability RSD was 2.40%, and the recovery rate was 94.25%-111.19%, and the content of tea polysaccharide was 54.76 mg/g. Conclusion Phenol-sulfuric acid method is suitable for the determination of tea polysaccharide in tea with DES as extraction solvent.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |