Phytochemical, medicinal, and industrial applications of marigold: A comprehensive review

Abstract

Marigold (Tagetes spp. and Calendula officinalis) is an economically and medicinally important crop widely cultivated for ornamental, pharmacological, and industrial purposes. Rich in carotenoids, flavonoids, terpenoids, phenolic acids, and essential oils, marigold exhibits potent antioxidant, anti-inflammatory, antimicrobial, anticancer, and wound-healing activities. Lutein, the dominant carotenoid, is extensively applied in nutraceuticals, ophthalmic supplements, poultry feed, and functional foods, accounting for over 85% of the global natural lutein supply. Additionally, marigold plays a vital role in the food industry as a natural colorant, in textiles as a dye source, and in agriculture as a bio-fumigant and soil enhancer. Global marigold cultivation spans more than 200,000 hectares, with India, China, and Latin America as major producers. Despite its potential, challenges such as lack of standardized extraction methods, limited clinical trials, post-harvest losses, and supply chain issues hinder optimal utilization. This review highlights the phytochemical diversity, medicinal properties, and industrial applications of marigold while addressing existing gaps and future prospects. With advances in molecular breeding, biotechnology, and sustainable processing, marigold holds promise as a high-value crop in the global nutraceutical and phytopharmaceutical industries.