[Effect of drying processing methods on different specifications of Sophorae Flos based on comprehensive statistical...

To investigate the effects of six common drying methods on the quality of different specifications of Sophorae Flos, in order to select their suitable drying methods. According to appearance and morphology, Sophorae Flos was divided into the following three specifications: flower bud type(HL), half-open type(BK) and blooming type(SK). All specifications of samples were treated with shade-drying method(25 ℃, natural temperature), sun-drying method, hot-air-drying method(60, 105 ℃), and drying method(60 ℃) after steaming. The contents of total flavonoids, rutin, narcissus, quercetin, isorhamnetin, and Fe~(3+) reducing ability, DPPH free radical scavenging ability, ABTS free radical scavenging ability and fluorescence recovery after photobleaching(FRAP) were detected by UV, HPLC and colorimetry, respectively. Principal component analysis(PCA), cluster analysis(CA) and correlation analysis were used to comprehensively evaluate the quality of samples. According to the results, there were significant differences in the effect of drying methods on different specifications of samples. The drying method(60 ℃) after steaming was suitable for HL and BK, while the hot-air-drying method(60 ℃) was suitable for SK. When the fresh medicinal materials could not be treated in time, they should be spread out in a cool and ventilated place. Under high and low temperature conditions, the quality of three specifications of Sophorae Flos would be reduced. The hot-air-drying method(105 ℃) and shade-drying method(25 ℃) were not suitable for the treatment of fresh flowers and flower buds of Sophora japonicus. There were obviously differences of chemical compositions and antioxidant activities among the three specifications of samples. Therefore, the specifications of medicinal materials should be controlled to ensure the uniform quality. The study provided the abundant data reference for the selection of appropriate drying methods for the three specifications of Sophorae Flos, and useful exploration for the classification and processing of medicinal materials of flowers.