Biological clocks, some clock-related diseases, and medicinal plants.

Progress in chronobiology thus far has been built on botanical field investigation records, experiments on the development of biological clocks, open questions, established rules, and molecular mechanisms. In this review, three clock-related diseases, namely cancer, Alzheimer's disease (AD), and depression, are discussed. Evidence-based mechanisms of action of active compounds, namely epigallocatechin-3-gallate (EGCG), curcumin, and melatonin, from three medicinal plants, Camellia sinensis K., Curcuma longa L., and Hypericum perforatum L., respectively, as potential therapies against cancer, AD, and depression, respectively, have been explained. Feedback loops of basic inputs and application outputs of various studies will lead to the development of chronobiology for applications in time-keeping, disease prevention, and control, and future agricultural practices.