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Two new 3,8-cyclized cembranoids, briarenols O (1) and P (2), featuring with briarane carbon skeleton have been isolated from a cultured octocoral Briareum excavatum. The structures of 1 and 2 were established by spectroscopic methods and 1 was found to be a rare 2-ketobriarane. Briarane 1 enhanced the generation of inducible nitric oxide synthase (iNOS) from RAW 264.7 stimulated by lipopolysaccharides (LPS).

Five 2-acetoxybriaranes, including two known analogues, excavatolides B (1), E (2), along with three new metabolites, briaviolides V–X (3–5), have been obtained from the octocoral Briareum violaceum. The absolute configurations of 1 and 2 were determined by X-ray analysis for the first time and the structures of 3–5 were established by spectroscopic methods. Bioactivity study showed that briarane 3 decreased the release of elastase from human neutrophils.

A known briarane, brianthein W (1), along with four new hydroperoxybriaranes, briaviolides R–U (2–5), have been obtained from the octocoral Briareum violaceum. The absolute configuration of 1 was determined by X-ray analysis for the first time and the structures of briaranes 2–5 were established by spectroscopic methods. Bioactivity study showed that briarane 3 decreased the production of superoxide anions from human neutrophils.

The marine red alga Pterocladiella capillacea is an economic alga for the food industry in Taiwan, and its associated highly diversified fungi have not been investigated meticulously thus far. The EtOAc extract of the fermented broth of Chondrostereum sp. NTOU4196, a fungal strain isolated from P. capillacea, was found to exhibit significant nitric oxide (NO) production inhibitory activity in lipopolysaccharide-activated murine RAW 264.7 cells at a concentration of 100 μg/mL in the preliminary screening. Therefore, separation of the active principles from the fermented broths was performed, and that has led to the isolation of eight new 5,5,5-tricyclic hirsutane-type sesquiterpenes, namely, chondroterpenes A-H (1-8), together with seven known analogues. They were identified by analyses of spectroscopic data and comparison with literature values. Among the new isolates, chondroterpene A (1) exhibited more significant NO production inhibitory activity in murine BV-2 microglial cells, and of all the isolated compounds, hirsutanol A (9) exerted limited cytotoxic effects and the most potent inhibitory activity on NO production.

The discovery of new natural products from fungi isolated from the marine environment has increased dramatically over the last few decades, leading to the identification of over 1000 new metabolites. However, most of the reported marine-derived species appear to be terrestrial in origin yet at the same time, facultatively halo- or osmotolerant. An unanswered question regarding the apparent chemical productivity of marine-derived fungi is whether the common practice of fermenting strains in seawater contributes to enhanced secondary metabolism? To answer this question, a terrestrial isolate of Aspergillus aculeatus was fermented in osmotic and saline stress conditions in parallel across multiple sites. The ex-type strain of A. aculeatus was obtained from three different culture collections. Site-to-site variations in metabolite expression were observed, suggesting that subculturing of the same strain and subtle variations in experimental protocols can have pronounced effects upon metabolite expression. Replicated experiments at individual sites indicated that secondary metabolite production was divergent between osmotic and saline treatments. Titers of some metabolites increased or decreased in response to increasing osmolite (salt or glycerol) concentrations. Furthermore, in some cases, the expression of some secondary metabolites in relation to osmotic and saline stress was attributed to specific sources of the ex-type strains.