AUTHOR=Zhao Hanyu , Xiong Miaomiao , Yang Xiaomin , Yao Lan , Wang Zeyan , Wang Li-an , Li Zhuang , Zhang Jinxiu , Lv Jianhua 

TITLE=Six new polyphenolic metabolites isolated from the Suillus granulatus and their cytotoxicity against HepG2 cells

JOURNAL=Frontiers in Nutrition

VOLUME=11

YEAR=2024

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2024.1390256

DOI=10.3389/fnut.2024.1390256

ISSN=2296-861X

ABSTRACT=<p>Edible mushrooms are an important source of nutraceuticals and for the discovery of bioactive metabolites as pharmaceuticals. In this work, six new polyphenolic metabolites suillusol A-D (<bold>1</bold>–<bold>4</bold>), suillusinoic acid (<bold>5</bold>), ethyl suillusinoate (<bold>6</bold>), were isolated from the <italic>Suillus granulatus</italic>. The structures of new compounds were elucidated using high-resolution electrospray ionization mass spectroscopy, nuclear magnetic resonance data, and single-crystal X-ray diffraction analysis. As far as we know, compound <bold>1</bold> represents an unprecedented type of natural product and compound <bold>3</bold> represents a new type of polyphenol fungal pigment, which may be biosynthetically related to thelephoric acid. The cytotoxicity against HepG2 cells of the new compounds were also evaluated. Compound 2 demonstrate significant inhibitory activity against HepG2 cells with IC<sub>50</sub> values of 10.85 μM, surpassing that of positive control cisplatin. Moreover, compound <bold>1</bold> and <bold>3</bold> also exhibited moderate cytotoxic activity with their IC<sub>50</sub> values measured at 35.60 and 32.62 μM, respectively. Our results indicate that <italic>S. granulatus</italic> is a rich source of chemical constituents that may provide new lead compounds for the development of anticancer agents.</p>