Diterpenoids from the Brown Alga Rugulopteryx okamurae and Their Anti-Inflammatory Activity

Abstract

Brown algae of the Family Dictyotaceae produce an array of structurally diverse terpenoids, whose biomedical potential in the anti-inflammatory area has been scarcely explored. Herein, the chemical study of the alga Rugulopteryx okamurae has led to the isolation of ten new diterpenoids: rugukadiol A (1), rugukamurals A–C (2–4), and ruguloptones A–F (6–10). The structures of the new compounds were established by spectroscopic means. Compound 1 exhibits an unprecedented diterpenoid skeleton featuring a bridged tricyclic undecane system. Compounds 2–10 belong to the secospatane class of diterpenoids and differ by the oxygenated functions that they contain. In anti-inflammatory assays, the new diterpenoid 1 and the secospatanes 5 and 10 significantly inhibited the production of the inflammatory mediator NO in LPS-stimulated microglial cells Bv.2 and macrophage cells RAW 264.7. Moreover, compounds 1 and 5 were found to strongly inhibit the expression of Nos2 and the pro-inflammatory cytokine Il1b in both immune cell lines.

Edible algae allergenicity – a short report

“…It is widely reported that algal species are good sources of fibre, various vitamins, minerals, and that several algal derived bioactives have anti-inflammatory properties when tested in models of inflammation (Lee et al 2017;Ismail et al 2020;Alkhalaf 2021;Cuevas et al 2021;Chen et al 2022;Mihindukulasooriya et al 2022). These beneficial properties have spawned growth in the algal food production industry and algal products are largely good for health.…”

A Concise Review on the Potential Applications of Rugulopteryx okamurae Macroalgae

“…Most of those address its use as biomass for anaerobic co-digestion, composting and biofertilizer production, and the development of bio-based plastic materials (bioplastics). Additionally, potential anti-inflammatory and antimicrobial activities have been suggested, as well as the ability to inhibit -glucosidase, which may be attractive features for the biomedical, pharmaceutical or food industries [ 12 ].…”

“…The search for new anti-inflammatory agents is of great relevance to the medical field since inflammation is associated with several difficult to treat diseases, such as some types of cancer, rheumatoid arthritis, inflammatory bowel disease and diabetes [ 12 ].…”

“…Some species, including R. okamurae , are characterized by producing a wide range of cyclic diterpenoids. These metabolites have a variety of carbon skeletons, which differ significantly between genera and can be useful chemotaxonomic markers [ 12 ]. They are composed of five carbon subunits (isoprenoids) arranged in a configuration called head and tail and are classified according to the number of isoprenoid units incorporated [ 41 ].…”

“…Despite still being incipient, research on potential applications of the macroalgae is also being performed as a way of minimizing the accumulation of macroalgae residue and the costs associated with its removal and elimination from affected regions [ 10 ]. This research gives value to the residue [ 11 ], transforming a problem into an opportunity for obtaining new marketable products [ 12 ].

Figure 1 Schematic representation of the taxonomic position of [ 13 ].

…”