Seasonal Variation in Phenolic Compounds and Antioxidant Activity in Leaves of Cyclocarya paliurus (Batal.) Iljinskaja

Abstract

Cyclocarya paliurus (Batal.) Iljinskaja is a plant with nutraceutical importance since its leaves have been used historically as folk medicines for hundreds of years. The content of 10 phenolic compounds was determined throughout the growing season by high-performance liquid chromatography (HPLC) with UV detector, while the antioxidant activities of C. paliurus leaf extracts were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS), and ferric reducing antioxidant power (FRAP) methods. Seasonal variations in phenolic concentration and antioxidant activity as well as linkage between the phenolic composition and antioxidant activity were assessed. A significant seasonal variation of phenolic compounds was observed in the leaves and the highest content appeared in May, July, and November. Seventy percent ethanol extract of C. paliurus leaves possessed a good radical scavenging potency. Meanwhile, a significant correlation between antioxidant activities and contents of phenolics was detected. Results of the relationship between molecular structures and their antioxidant activities showed that both the number and configuration of H-donating hydroxyl groups are the main structural features influencing the antioxidant capacity of phenolics, while glycosylation may reduce the antioxidant capacity. The information provided by this study not only revealed the accumulative dynamics of phenolic compounds, but also established a basis for determining the optimal time for harvesting to improve the content of beneficial compounds in the leaves of C. paliurus in the future.

Calligonum polygonoides L. as Novel Source of Bioactive Compounds in Hot Arid Regions: Evaluation of Phytochemical Composition and Antioxidant Activity

“…Our result is in accordance with the recent reports, which suggested that higher phenolic content exhibited stronger antioxidant activity. A similar linear correlation was also reported in Moringa oleifera, Cyclocarya paliurus leaves, Juglans sigillata husk, Ocimum basilicum leaves, and Juglans regia [17,[28][29][30][31]. Moreover, the correlation coefficient between phenolic compounds and total antioxidant activity in CUPRAC and DPPH assay (r 2 > 0.91, p < 0.05) is stronger than that of antioxidant activity in FRAP assay (r 2 < 0.80, p < 0.05).…”

The Influence of Solvent, Host, and Phenological Stage on the Yield, Chemical Composition, and Antidiabetic and Antioxidant Properties of Phragmanthera capitata (Sprengel) S. Balle

“…The levels of secondary metabolites in plants can vary depending on the environmental conditions and the stage of development of the plant [ 51 ]. Phenolic compounds, which are one of the main groups of secondary metabolites, are not an exception.…”

“…Thus, both the hosts and P . capitata are under favorable photosynthetic conditions (sunshine, abundance of minerals, and water) [ 51 ], boosting the rate of secondary metabolite biosynthesis in these plants [ 52 ]. At the same time, in this study, the rate of production of total tannins decreased from the vegetative phase to the fruiting stage, certainly passing to flowers.…”

Secondary Metabolic Profile as a Tool for Distinction and Characterization of Cultivars of Black Pepper (Piper nigrum L.) Cultivated in Pará State, Brazil

“…However, in the fruits we noticed only small changes in the "Cingapura" and "Uthirankota" cultivars (Figure 4B). According to the literature, these variations can be occasioned by several factors, biotic and abiotic, such as plant defense, senescence, plant development, and interactions with the environment in which they are inserted [84]. The levels of total phenolics were higher in the leaves in comparison to the fruits.…”