Abstract: To improve the nutritional and functional values of rice, numerous biotechnological attempts have focused on metabolic engineering to address nutritional deficiencies and produce health-beneficial compounds that are either absent or naturally present in low amounts. A prominent example is ‘Golden Rice’, which has been engineered to accumulate β-carotene to combat vitamin A deficiency in areas where its intake is limited. Scientists have continuously biofortified rice with various specialized metabolites, including terpenoids, flavonoids, non-flavonoid polyphenols, betalain, vitamins, and amino acids. We explored the specific pathways and genetic modifications utilized by researchers to accumulate targeted metabolites in rice. This survey comprehensively provides the key strategies and research trends in rice metabolic engineering. Thus, we suggest that rice can become a strategic crop for producing industrially valuable substances beyond its role as a food crop by leveraging its advantages as a host system through its grains, leaves, and cells. In addition, we highlight the potential of combining metabolic engineering with synthetic biology and big data-driven computational modeling based on artificial intelligence and machine learning for future research directions and challenges.

Key words: agrobiotechnology, biofortification, biofoundry, plant metabolic engineering, rice cell suspension culture