What is the one component in photosynthesis that is not recycled?

One component in photosynthesis that is not recycled is water. During the light-dependent reactions of photosynthesis, water molecules are split into oxygen, protons, and electrons. The oxygen is released as a byproduct, while the protons and electrons are used to generate ATP and NADPH, which are necessary for the Calvin cycle (the light-independent reactions) to create glucose. Since water is essential for this process and is broken down irreversibly, it is not recycled in the same way that other components, such as carbon dioxide and ATP, are in the photosynthetic process.