The nitrogenous metabolites of pea (Pisum sativum L.): A phytochemical and pharmacological overview

Pisum sativum L. (pea) is a rich leguminous source of many primary and secondary metabolites that underpin its nutritional, health-promoting, and medicinal traits. This plant flourishes in a symbiotic relationship with rhizobia that inhabit its root nodules, giving rise to biological nitrogen fixation aptitude. In exchange for sugars produced by pea, such soil bacteria help convert atmospheric nitrogen into ammonium compounds that are then utilized by pea plants. This nitrogen-fixing capacity has therefore allowed different parts of P. sativum to accumulate structurally diverse nitrogenous principles, including proteinogenic and non-proteinogenic amino acids, oligopeptides, polypeptides, lectins, biogenic amines, alkaloids, nitrogenous bases, indoles, phospholipids, and cerebrosides. A considerable amount of research has also unveiled the protective and therapeutic potential of many of these metabolites against microbial infections, oxidative stress-related disorders, inflammation, and metabolic diseases (e.g. diabetes, hyperlipidemia, hypercholesterolemia, obesity, hypertension, and renal fibrosis), while some others revealed allelopathic, antifeedant, and insect repellent properties. Therefore, this review offers a comprehensive overview on the chemical diversity and pharmacological aspects of various nitrogen-containing metabolites produced by P. sativum; highlighting their contribution to the health outcomes of this valued herb and its possible application in future phytotherapy and drug development.