Functional Components and Antioxidant Activity of Aralia elata Leaves at Different Harvesting Periods

To provide a theoretical basis for the timely harvesting of Aralia elata, the cultivated A.elata was used as experimental materials, and the biomass, photosynthetic pigment content,, total phenolic content, total flavonoid content and antioxidant capacity of A. elata leaves in different harvesting periods（S1 period, April 10th, 2023; S2 period, April 30th, 2023; S3 period, May 20th, 2023; S4 period, June 9th, 2023） were analyzed respectively. Meanwhile, the high-performance liquid chromatographic（HPLC） method was established to determine the contents of araloside X, araloside V,and araloside A. Based on high-performance lAiq. ueilda tcahromatography-mass spectrometry metabolomics technology, the differences in secondary metabolites of, at different harvesting periods were compared and analyzed. The results showed that:（ 1）The fresh weight dry weight, and photosynthetic pigment content of A. elata leaves increased with growth, and reached the maximum value in the S4 period.（ 2）The contents of total phenol and total flavone reached the maximum value in the S1 period(1.36 mg·g^-1, 29.38 mg·g^-1).（3）The scavenging ability of DPPH radical was the strongest in t(he S1 period(ICIC50 of 0.262 g·L^-1) and the scavenging ability of ABTS radical was the strongest in the S2 period 50 of 0.511 g·L^-1).（ 4）The content of araloside A reached a maximum of 12.90 mg·g^-1 in the S4 period. The contents of araloside V and X in the S2 period were significantly higher than those in other periods, which were 1.53 and 3.30 mg·g^-1 respectively.（ 5）A total of 24 phenolic metabolites were identified, and the total amount of phenolic compounds in the four periods were 64.84, 119.31, 101.95 and 89.32 mg·g^-1, respectively.)Among the total phenolic compounds, the C6C1 backbone compounds( protocatechuic acid and gentisic acid, the C6C3C6 backbone compounds（ rutin）, and the C6C3 backbone compounds（ caffeic acid） were signifi,cantly accumulated in the S2 period. In conclusion, considering the content of functional components antioxidant activity, and edibility, the S2 period is the most suitable time for harvesting.