Marinacarboline glucuronide, a new member of β-carboline alkaloids from sponge-derived actinomycete Actinoalloteichus cyanogriseus LHW52806.

A new member of β-carboline alkaloids, Marinacarboline glucuronide (1), along with nine known compounds (2-10), were isolated from static liquid fermentation extracts of Actinoalloteichus cyanogriseus LHW52806 isolated from the marine sponge Phakellia fusca. Their structures were elucidated by NMR, mass spectrometry and single-crystal X-ray diffraction. All compounds exhibited neither antimicrobial activity nor cytotoxicity. Compounds 1, 8 and 10 showed anti-inflammatory potential of significant decreasing the expressions of IL- 6 in vitro at 20 µM.