Turning the sea into medicine: Ocean University of China discovers 14 new compounds in soft coral with anti-inflammatory and antithrombotic potential

Marine soft corals have long been recognized as a treasure trove of structurally novel and biologically active natural products. Among them, Clavularia species are particularly prolific producers of terpenoids, especially the dolabellanes — a family of diterpenes with a characteristic fused bicyclic framework, first discovered in sea hares of the Dolabella genus. Dolabellanes have shown cytotoxic, antimicrobial, and antiviral properties, positioning them as valuable lead compounds for pharmaceutical development. However, the chemical diversity of Clavularia koellikeri — a species found in Indo-Pacific coral reef waters — had remained largely unexplored.

□ To unlock this untapped resource, the research team extracted 9.7 kg of soft coral biomass and, through systematic chromatographic separation guided by LC-MS analysis, isolated fourteen new dolabellane-type diterpenes. The structures were established through an integrated strategy combining NMR spectroscopy and high-resolution mass spectrometry, while their absolute configurations were unambiguously assigned using quantum-chemical ECD spectral simulations and DP4+ probability analysis. Notably, several of the new compounds feature rare structural motifs — including epoxide-bearing variants and a unique tricyclic rearrangement of the classical dolabellane skeleton — that expand the known chemical space of this terpene family.

□ Functional evaluation delivered encouraging results. In a transgenic zebrafish model of inflammation, compounds 8 and 13 significantly reduced inflammatory cell recruitment, performing comparably to the clinical anti-inflammatory drug indomethacin. More strikingly, all fourteen compounds demonstrated antithrombotic activity in an arachidonic acid-induced zebrafish thrombosis model — with most compounds outperforming aspirin, the widely used positive control drug, in reducing venous thrombus formation.

□ Thrombotic diseases — including heart attack, stroke, and venous thromboembolism — remain among the world’s leading causes of death and disability, and the discovery of a suite of marine-derived molecules with aspirin-beating antithrombotic activity in vivo offers a valuable starting point for the development of next-generation anticoagulant and antiplatelet therapies.

□ “This study demonstrates both the remarkable structural creativity of South China Sea soft corals and their pharmacological potential,” the research team noted. “Compounds 1–4, 7–10, and 12–13 exhibited antithrombotic activities superior to the positive control, warranting further mechanistic investigation and preclinical development.”

□ This research was conducted at the Key Laboratory of Marine Drugs of the Chinese Ministry of Education (Ocean University of China) in collaboration with the Biology Institute of Qilu University of Technology (Shandong Academy of Sciences). Zhongyu Lu, Xiao Zhu, and Xin Zhou contributed to the work, with Dr. Xiao Han and Professor Guoqiang Li as corresponding authors. The findings were published in the Chinese Journal of Natural Medicines (2026, 24(9), 1123–1128), and the work was supported by the National Key R&D Program of China, the China Postdoctoral Science Foundation, and the Shandong and Qingdao Postdoctoral Science Foundations.
*Corresponding authors: Dr. Xiao Han (hanxiao@ouc.edu.cn); Prof. Guoqiang Li (liguoqiang@ouc.edu.cn)*
*Paper DOI: https://doi.org/10.1016/S1875-5364(26)61209-5