Bioactive Components and Antioxidant Activities of Different Parts of Cistanche tubulosa in Qinghai Province

In this paper, the bioactive components and antioxidant activities of Cistanche tubulosa (CT) cultivated in Qinghai Province were comprehensively analyzed. The results showed that the bioactive components in different parts of Cistanche tubulosa were significantly different (P<0.05). Contents of total polyphenols, total polysaccharides, total triterpenes, echinoside and verbascoside in bottom part were significantly higher than those in the middle and top parts. Especially, the contents of the total echinoside and verbascoside content was 4.67%, which was higher than the standard of Chinese pharmacopoeia 2020 edition. The IC₅₀ values of ABTS free radical scavenging abilities of root, middle and top parts were 0.91, 1.59, 2.32 mg/mL, respectively. The IC₅₀ values of DPPH free radical scavenging activities were 0.77, 5.16, 10.66 mg/mL, respectively. The antioxidant activities of different parts of Cistanche tubulosa were closely related to the contents of various bioactive substances, the IC₅₀ value of ABTS and DPPH were negatively correlated with the contents of total polyphenols, total triterpenoids, total polysaccharides, echinoside and verbascoside, and the correlation coefficient was high. The results will provide a theoretical basis for the medicine, food safety and utilization of Cistanche tubulosa in Qinghai Province.