H₂O₂improves quality of Radix scutellariae through anti-oxidant effect

Abstract

Introduction:The correlation between the quality and geographical origin of herbal medicine was traced back to Tang Dynasty in China, more than 1200 years, and the effects of ecological environments on the secondary metabolites such as flavonoids have been confirmed. However, little is known about how the adversity impacts on the quality. Reactive oxygen species (ROS) may be medium between the ecological environment and the secondary metabolism.Materials and Methods:The fresh roots of Scutellaria baicalensis Georgi were treated with 0.002 μmol/L, 0.2 μmol/L, and 20 μmol/L H2O2, respectively. A stress model was established to elucidate the change of secondary metabolism, anti-oxidant enzyme system, and enzymes relating to flavonoids.Results:The activities of superoxide dismutase, catalase and peroxidase decreased. Too much H2O2, firstly, boosted transformation of flavonoids glycoside into aglucon with the most remarkable activities through UDP-glucuronate baicalein 7-O-glucuronosyltransferase (UBGAT), and β-glucuronidase (GUS), then regulated the gene expression of phenylalanine ammonialyase, GUS, and UBGAT, and increased the contents of flavones, motivated the flavonoid glycoside converting into aglucon. With this action, the flavones displaced the anti-oxidant enzymes. The higher the dosage, the more baicalein and wogonin increased, the later they took action.Conclusion:The plant secondary metabolites to keep ROS constant are identical to the effective materials in clinic. They are closely linked. H2O2 can improve flavones, especially the aglucon, and further increased the quality of herbal medicine, which possesses very important value in medical practice.SUMMARY H2O2 decreasing the activities of CAT and POD lead to accumulation of more H2O2. Excess of H2O2 up-regulated PAL, BUG, promote biosynthesis of flavones, and enhance the nonenzyme system. “↑” and “↓” represent activity or content “up” and “down” respectively.

Complexity of active medicinal ingredients in radix scutellariae with sodium hydrosulfite exposure

“…The contents of baicalin, wogonoside, and chrysin are all high in the natural state, and furthermore, these reactions are fulfilled by only one step; therefore, the reaction was swiftly performed. Second, ROS can increase the activity of phenylalanine ammonialyase (PAL) [20,32], continuously replenishing flavonoids.…”

Sodium dithionite-enhanced quality of radix scutellariae through modification of secondary metabolism

“…The previous research proved that under the stress, the flavonoids contribute more significantly than the antioxidases. [15] In our study, the PALs were highly expressed, the antioxidases slightly increased, flavonoids must be do excellent service in eliminating ROS.…”

Seed Characteristics of Passion Fruit (Passiflora edulis f. flavicarpa) Rootstocks with Different Genotypes and Responses of Their Seedlings to Drought Stress

“…As previously reported, exceeding the total oxidation potential of cells will induce oxidative stress, affecting plant growth (Qi et al, 2023) synthesis after drought stress. It should also be noted that H 2 O 2 in leaves can be accurately regulated through the complex regulation of CAT mRNA (Luna et al, 2004) and that H 2 O 2 can reduce the activity of POD, resulting in the accumulation of more H 2 O 2 in plants (Song et al, 2016). The results here also confirmed that the activity of CAT and POD was reduced after the drought stress treatment, leading to the continuous accumulation of H 2 O 2 and thereby causing irreversible damage to the plants.…”