Valorization of ligustrum species: biosynthesis, metabolic engineering, and pharmacology of bioactive compounds

The genus Ligustrum (Oleaceae) encompasses woody plants with both medicinal and edible uses, distinguished by a wide range of bioactive compounds, including triterpenoids, phenylethanoid glycosides, flavonoids, and other active constituents. These metabolites demonstrate multi-target pharmacological effects, such as anti-inflammatory, antioxidant, antitumor, and anti-osteoporotic activities. In traditional medicine, species like L. lucidum and L. robustum are well-documented for their therapeutic roles in nourishing the liver and kidneys, enhancing vision, darkening hair, and serving as functional tea ingredients. Beyond their medicinal and health-promoting properties, Ligustrum species are also employed as ornamental plants, bioindicators of atmospheric pollution, algicidal agents, and feed additives. Given the increasing global demand and underutilization of Ligustrum resources, there is an urgent need to establish a sustainable supply framework focused on alternative strategies such as metabolic engineering, synthetic biology, and environmentally friendly manufacturing. This review encapsulates recent progress in the exploration of chemical diversity, pharmacological characteristics, omics-based analyses, and biosynthetic research pertaining to Ligustrum. It proposes an integrated methodology that amalgamates multi-omics approaches, synthetic biology, and environmentally sustainable manufacturing processes to advance strategies for whole-plant valorization and germplasm conservation. The objective is to establish a theoretical framework and technical paradigm to facilitate the comprehensive exploitation and sustainable utilization of Ligustrum as a medicinal resource.