Phytochemicals and Their Chemical and Biological Properties

Abstract

Phytochemicals are naturally occurring chemical constituents produced by plants and include diverse classes such as alkaloids, flavonoids, phenolic acids, terpenoids, tannins, saponins, and glycosides. These compounds contribute to plant defense, adaptation, signaling, pigmentation, and interactions with the environment. Their chemical structures determine properties such as polarity, solubility, stability, reactivity, and interactions with biological targets. Phytochemicals have attracted scientific interest because of reported antioxidant, antimicrobial, anti-inflammatory, enzyme-modulating, and other biological activities. This paper examines major dimensions of phytochemicals and their chemical and biological properties, including chemical classes, structure-function relationships, plant functions, extraction, antioxidant activity, antimicrobial effects, pharmacological relevance, safety, and emerging applications.