Amino Acids & Proteins
Amino acids, peptides, and proteins — including directly bioactive free amino acids and plant proteins.
Amino acids are the nitrogen-containing building blocks of life: small molecules that link together through peptide bonds to form peptides and, at greater length and complexity, proteins. This nitrogen backbone is their defining feature, setting them apart from the carbon-and-oxygen scaffolds of most other plant constituents. A handful of the standard twenty amino acids, along with various non-protein amino acids unique to plants, circulate in free form and carry biological activity in their own right.
As a class they are universal and utterly essential — every living plant cell depends on proteins for its enzymes, its structure, and its metabolism, and on free amino acids as the currency of nitrogen transport and storage. For a phytochemistry reference, however, the interest lies less in this bulk nutritional role and more in the specific free amino acids and discrete proteins that are directly bioactive, acting on the body as agents rather than merely feeding it.
What qualifies here, then, is the pharmacologically interesting fraction. The overall pattern is reassuring: free amino acids such as L-theanine and GABA are generally very safe and tend towards the calming and nourishing, and are widely taken for exactly those qualities. The genuine exception is a small group of plant proteins — the ribosome-inactivating proteins and certain toxic lectins, found in plants such as elder and dwarf elder — which can be dangerous. So the class is mostly benign, with a few proteins that are truly toxic.
Browse all amino acids & proteins in the filterable index ›
Amino Acids (24)
The building blocks of proteins, and among the simplest bioactive molecules a plant can offer. Several free amino acids are directly active rather than merely nutritional: L-theanine, characteristic of tea, is calming and cognition-supporting, while GABA acts as the body's principal inhibitory neurotransmitter. As a group they are common and generally very safe, tending towards gentle, nourishing, and settling effects, though plants also make unusual non-protein amino acids with more specialised activity.
Proteins & Peptides (23)
Larger nitrogen-based constructs — chains of amino acids folded into peptides, enzymes, and full proteins. Most are benign or beneficial, including the digestive and defensive enzymes plants deploy throughout their tissues. This subgroup, however, holds the class's real hazard: the ribosome-inactivating proteins and toxic lectins, such as those in elder and dwarf elder, which can disrupt protein synthesis and cause serious poisoning. A small but genuinely toxic minority within an otherwise gentle class.