Active Polyphenols, also known as APP®, are secondary plant metabolites, including phenolic acids, flavonoids, tannins, stilbenes, and important organic acids. As plants are immobile, often they encounter potential enemies such as herbivores, predators,
microbes, viruses, or competing plants. They also face abiotic stress conditions such as salt, drought,
or high‐intensity light. So naturally, they need some defence mechanism or a group of compounds to
fight against the above. These are classified as APP®.