A Comprehensive Monograph on Lycopene (DB11231): Chemical Profile, Biological Activity, and Clinical Evidence

1.0 Executive Summary

Lycopene is a naturally occurring tetraterpene carotenoid, a lipophilic pigment responsible for the characteristic red color of tomatoes, watermelon, and other fruits. Chemically identified by the formula $C_{40}H_{56}$ and CAS number 502-65-8, it exists predominantly in the all-trans isomeric form in nature, though numerous cis-isomers are formed during processing and are prevalent in human plasma. As a non-provitamin A carotenoid, its biological significance stems not from vitamin activity but from its potent antioxidant and anti-inflammatory properties. Its unique structure, featuring 11 conjugated double bonds, makes it one of the most effective quenchers of singlet oxygen and other reactive oxygen species (ROS) among dietary carotenoids.

The biological mechanisms of lycopene are multifaceted, extending beyond simple antioxidant defense. Evidence indicates that it modulates key cellular pathways involved in inflammation, proliferation, and intercellular communication. It has been shown to suppress pro-inflammatory cytokines, interfere with growth factor signaling, induce cell cycle arrest in cancer cells, and restore gap junctional communication—a process often lost during carcinogenesis. This complex bioactivity forms the basis for its investigation in the prevention of chronic diseases.