Broccoli (Brassica oleracea L. Italica group) is a widely consumed cruciferous vegetable valued for its gastrointestinal and immune health benefits. However, the individual contributions and interactions of broccoli glucosinolates, as they hydrolyze into bioactive isothiocyanates, remain poorly understood. This study investigated mixtures of four major aliphatic glucosinolates-glucoraphanin, gluconapin, progoitrin, and sinigrin-in individual and combinational models to assess their effects on human colorectal cell proliferation. Combination index analysis revealed moderate to strong antagonistic interactions among these glucosinolates, with the most significant antagonism observed during enzymatic hydrolysis by myrosinase. Mixture analysis identified an optimal glucosinolate ratio including glucoraphanin (81-84%), gluconapin (9-19%), and others (0-7%) to maximize their antiproliferative effects (adjusted R2 > 0.80). This optimal profile was achievable within the target broccoli mapping population. Testing the near-optimal VB067 isogenic broccoli line showed a 44% increase in antiproliferative activity compared to the initial breeding parent or an average sister line. This study highlights the potential of leveraging nutrient-nutrient interactions to guide molecular breeding and produce functional varieties of cruciferous vegetables with optimized health benefits.
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