When autumn arrives, the leaves on maple trees slowly transform into a vibrant red hue. From a distance, the mountains become a sea of red, creating a truly spectacular scenery.

But why does this happen? It turns out that, aside from chlorophyll, there are various pigments in plant leaves, such as lutein, carotene, and anthocyanins, which change color based on the pH level.

The captivating display of autumn leaf colors is primarily linked to these pigments.

The primary factor for the change in leaf color is the decrease in chlorophyll. During the fall and winter, deciduous trees enter a self-dormant adjustment stage, storing nutrients in the trunk or roots for the upcoming spring.

Since chlorophyll cannot be synthesized in large quantities during this period, it gradually breaks down due to chlorophyllase decomposition or photo-oxidation, resulting in a reduction in its levels. Consequently, leaves lose their green appearance in the fall and winter.

When chlorophyll diminishes, other pigments, such as yellow carotenoids (lutein, carotene) and anthocyanins, become more prominent.

Anthocyanins, known for coloring flower petals and fruits, are found in various fruits like blueberries, blackberries, cranberries, and others.

Scientifically proven to be beneficial to the human body, anthocyanins act as potent antioxidants, protecting against damage from free radicals.

Additionally, they enhance blood vessel elasticity, improve the circulatory system, promote skin smoothness, inhibit inflammation and allergies, and boost joint flexibility.

Anthocyanins are water-soluble pigments that change color with the acidity of cellular fluid. They appear reddish in an acidic environment, bluish in an alkaline environment, and purple when the environment is neutral.

In the fall, as chlorophyll breaks down due to decreasing temperatures, the cellular leaf's acidity changes. This acidic environment causes anthocyanins to turn red.

The sugars stored in the leaves further aid in converting anthocyanins, intensifying the red coloration of the leaves.

As autumn progresses and weather conditions change, plants like maple trees experience an increase in anthocyanins, transitioning from green to red.

Plant leaves undergo further chlorophyll destruction due to frost, while sugar stored in the branches and leaves increases.

This dual process contributes to the leaves taking on varying shades, including bright red, deep red, and purple-red, depending on the concentration of anthocyanin and sugar.

In addition to the captivating autumnal leaf transformation, the role of anthocyanins extends beyond aesthetics. The vibrant hues serve as nature's palette, showcasing the intricate interplay between biochemical processes, weather changes, and the resilience of plant life.