Fig. 3

Proposed biosynthetic pathway of steroidal glycoalkaloids (SGAs) in potatoes. The figure illustrates the key steps involved in SGA biosynthesis, with solid arrows representing confirmed reaction stages and dashed arrows indicating steps that require further elucidation. The diagram highlights the distinct glycosidic units between α-solanine and α-chaconine, denoted by a green background, and emphasizes the crucial chemical differences between spiro- and solanine-type SGAs, indicated by a yellow background. For a comprehensive understanding of each step, please refer to the detailed description in the main text