<p>1-Deoxynojirimycin (DNJ) is a potent α-glucosidase inhibitor with considerable potential for functional foods. However, its application is constrained by low natural abundance and limited sources. Through a visualized bibliometric analysis of DNJ research (1994–2023) using Citespace and VOSviewer, this review reveals a distinct evolutionary trajectory: early efforts concentered on source discovery and bioactivity validation whereas the current frontier has shifted toward biosynthesis and yield enhancement, particularly via microbial engineering. Building on these insights, the multifaceted bioactivities of DNJ were systematically discussed. A critical emphasis on comparing biosynthetic pathways in plants and microbes is confirmed by evaluating the DNJ sources and extraction methods. Microbial fermentation is identified as the most scalable platform for sustainable production. In addition, the applications in DNJ-fortified foods are discussed. Future perspectives highlight that integrating metabolic engineering with fermentation optimization is key to overcoming the production bottlenecks, guiding the next phase of DNJ research and development.</p> Graphical abstract <p></p>