Temporal Variations in Enzymatic and Non-Enzymatic Antioxidant Activity in Silver Birch (Betula pendula Roth.): The Genetic Component

Betula pendula Roth. (silver birch) is a pioneer species in the Northern Hemisphere forests. It plays a significant role in various ecosystems, human industries, and biodiversity. Taking all this into account, understanding the genetic diversity within B. pendula populations is crucial for fully exploiting their potential, particularly regarding their production of phenolic compounds and antioxidants. We tested the non-enzymatic and enzymatic antioxidant activity in seven silver birch half-sib family leaves. Spectrophotometric data from leaf extracts showed that there was a significant variation between families in terms of total phenol content (TPC) and antioxidant enzyme (superoxide dismutase, peroxidase (POX), catalase, glutathione reductase, and ascorbate peroxidase) levels. The data were gathered during two consecutive seasons, resulting in a variance in antioxidant production, which generally increased in the tested families during the second year (except for POX) as opposed to the first vegetative season. For example, SOD levels increased in the second year by 15% to 243% and TPC increased by 46%–189%, depending on the half-sib family. A more thorough study of this variation should prove beneficial in various research fields, ranging from climate change to cosmetics.