Already since our predecessors, the alchemists, we know that plants can serve in many different applications. The term phytochemistry means chemistry of plants, which is a branch of chemistry and botany and is concerned with the chemical compounds and processes in plants. Compounds produced during the lifecycle of a plant can be divided into primary and secondary metabolites. Primary metabolites are important for essential functions, such as growth and development. Secondary metabolites have different specific functions and contribute to the fitness by interacting with the ecosystem and in further consequence by adaptation of the plant to their environment. They often occur in dedicated cells or specialised organs for instance the glandular hair of primroses. Plants use them also for defence against insects, bacteria, fungi or viruses and against oxidative stress (antioxidants). On the other hand secondary metabolites can also serve as attractants like floral pigments in flowers or volatile odorous substance. They can be widely distributed or be restricted to a specific group of plants so they can be used as chemotaxonomic markers . Secondary metabolites are separated into three classes of compounds due to their biogenesis:
Because of the large diversity of secondary metabolites and many benificial effects on the human organism, they are especially of interest for phamacology and medicine. Different separation methods are used to isolate secondary metabolites, for example liquid-liquid extraction, distillation or distinct chromatographies .
One focus of alchemia-nova is the research in different applications of phytochemistry.
> Green Chemistry
 Pharmakognosie-Phytopharmazie; Hänsel, Sticher, Steinegger; Springer-Verlag, New York, 6.Auflage 1999
 Rosenthaler L. (1928) Kurzer Abriß der Geschichte der Pflanzenchemie. In: Grundzüge der chemischen Pflanzenuntersuchung. Springer, Berlin, Heidelberg