Research progress on plant methylated flavonoids and their O-methyltransferases
Flavonoids are rich in fruits, vegetables, beans and tea. They have attracted much attention due to their antidepressant, anti-inflammatory, anti allergic, anti diabetes, anti-aging, anti-cancer and other medicinal functions. The structure of flavonoids is closely related to their biological functions. O-methylated flavonoids are flavonoids containing the OCH3 gene, which play an important role in plant root nodule nitrogen fixation, attracting insect pollination and other growth and development processes, as well as stress resistance reactions such as insect resistance, disease resistance, and weed resistance. Research has confirmed that O-methylated flavonoids have stronger antioxidant, anti-inflammatory, and anticancer functions, as well as higher bioavailability and medicinal value. Flavonoid O-methyltransferase (FOMT) belongs to the O-methyltransferase (OMT) subfamily and catalyzes the synthesis of O-methylated flavonoids from flavonoids. FOMT is widely present in plants. This article reviews the structure and function of O-methylated flavonoids, as well as the influence of OCH3 groups on their function; This paper summarizes the current research status of FOMT and conducts bioinformatics analysis to provide reference for further research and application development of O-methylated flavonoids and FOMT.

For a long time, the medicinal value and biosynthetic regulation of plant flavonoids have received much attention, but the low bioavailability of flavonoids limits their medicinal development. Methylation modification can improve the metabolic stability and in vivo transport capacity of flavonoids, enhance their bioavailability, and compensate for their shortcomings in clinical applications. In recent years, the research on O-methylated flavonoids and FOMT in plants has become a hot topic. With the deepening of plant genomics research, a large number of FOMT genes in plants have been discovered, but there are still few FOMT genes that have been fully functionally validated. At present, research on FOMT mostly adopts in vitro enzyme catalysis, biochemical characteristic analysis and other methods, and only a few FOMT genes have been functionally validated in vivo. Research on the regulation of FOMT gene expression is even more scarce. With the deepening of research on O-methylated flavonoids and FOMT, FOMT is expected to be used for the industrial production of O-methylated flavonoids, providing cost-effective raw materials for the production of related pharmaceutical and health products; In addition, O-methylated flavonoids are also important stress resistant metabolites in plants, and FOMT has great potential for application in the development of green pesticides and crop resistance breeding.