**3. Discussion**

Red yeas<sup>t</sup> rice has been used in food and traditional Chinese medicine since ancient times. In recent years, research has also found that red yeas<sup>t</sup> rice bacteria can produce many active secondary metabolites. In order to further explore the efficacy of different strains of red yeas<sup>t</sup> rice and expand the application range of red yeas<sup>t</sup> rice, in this study, a strain wmd2424 was isolated from the mangrove forest in Chiayi Wetland, and the strain was identified as *Monascus purpureus* via the results of colony culture morphology, microstructural characteristics, and partial sequence analysis of the β-tubulin gene fragment. After liquid fermentation using RGY medium, extraction with ethyl acetate, and analysis of its metabolites, a total of six new compounds were obtained.

To the best of our knowledge, this is the first report of isoquinoline-type metabolites from the edible fungi genus *Monascus*. These results demonstrate that *Monascus* produces unique and diverse metabolites in different fermentation conditions and soil-derived collections. Therefore, in a special ecological environment, more natural products with biological activity may be found by searching for *Monascus* species.
