Harnessing Light Wavelengths to Enrich Health-Promoting Molecules in Tomato Fruits

The tomato (Solanum lycopersicum L.) is one of the most consumed crops worldwide and a source of antioxidants. Given the role the latter play against oxidative stress and free radical-related diseases, enhancing tomato bioactive compound production would be appealing for a wide range of applications in the fields of nutrition, pharmacy, and biotechnology. This study explores a sustainable and innovative approach: the modulation of specific light spectra to boost the production of bioactive compounds in tomatoes (cultivar ‘Microtom’). We investigated how three light regimes—white fluorescent (FL), full-spectrum (FS), and red-blue (RB)—influence the accumulation of polyphenols and other key nutraceuticals during plant growth. Our findings reveal that full-spectrum (FS) light significantly enhances the levels of polyphenols, flavonoids, tannins, ascorbic acid, and lycopene in tomato fruits, compared to those grown under RB or FL light. Interestingly, fruits from RB light-grown plants showed the highest carotenoid concentrations and antioxidant capacity. These results suggest that light quality actively modulates the expression of key enzymes in the phenylpropanoid and flavonoid biosynthetic pathways, shaping each fruit’s unique metabolic fingerprint. Cluster analysis confirmed that RB, FL, and FS conditions lead to distinct polyphenolic profiles, each with notable health-promoting potential. Our results highlight a promising avenue: tailoring light environments to enhance the functional value of crops, bridging agriculture, nutrition, and biomedicine in a sustainable way.