Terpenoids as plant antioxidants.

Area of Science:

• Plant biochemistry
• Nutritional science
• Pharmacology

Background:

• Plant antioxidants encompass diverse compounds like ascorbic acid, tocopherols, polyphenols, and terpenoids.
• These compounds play vital roles in plants (e.g., photoprotection) and human health (e.g., vision, immune function).
• Carotenoids, monoterpenes, and diterpenes exhibit significant antioxidant capacities, contributing to the health benefits of fruits and vegetables.

Purpose of the Study:

• To review the diverse functions and mechanisms of plant antioxidants, particularly terpenoids.
• To discuss the antioxidant activity of carotenoids, monoterpenes, and diterpenes, including novel findings on gamma-terpinene.
• To explore the potential of plant-derived compounds like limonene and perillyl alcohol in cancer therapy.

Main Methods:

• Detailed discussion of antioxidant action mechanisms of carotenoids (singlet oxygen quenching, hydrogen/electron transfer).
• In vitro investigation of antioxidant activity of monoterpenes, diterpenes, and essential oils.
• Analysis of synergistic effects between different types of antioxidants.

Main Results:

• Carotenoids exhibit multiple antioxidant mechanisms and are crucial for vision and immune function.
• Monoterpenes and diterpenes, components of essential oils, have diverse roles and potential therapeutic applications.
• Gamma-terpinene is identified as a potent antioxidant, and synergistic effects were observed with combinations like rutin and gamma-terpinene.

Conclusions:

• Plant antioxidants, especially terpenoids, possess significant health-promoting properties.
• Understanding antioxidant mechanisms and interactions is crucial for harnessing their full potential.
• Further research into compounds like gamma-terpinene and synergistic combinations may lead to novel therapeutic strategies.