Polar marine biota have adapted to thrive under one of the ocean’s most inhospitable scenarios, where extremes of temperature, light photoperiod and ice disturbance, along with ecological interactions, have selected species with a unique suite of secondary metabolites. Organisms of Arctic and Antarctic oceans are prolific sources of natural products, exhibiting wide structural diversity and remarkable bioactivities for human applications. Chemical skeletons belonging to terpene families are the most commonly found compounds, whereas cytotoxic antimicrobial properties, the capacity to prevent infections, are the most widely reported activities from these environments. This review firstly summarizes the regulations on access and benefit sharing requirements for research in polar environments. Then it provides an overview of the natural product arsenal from Antarctic and Arctic marine organisms that displays promising uses for fighting human disease. Microbes, such as bacteria and fungi, and macroorganisms, such as sponges, macroalgae, ascidians, corals, bryozoans, echinoderms and mollusks, are the main focus of this review. The biological origin, the structure of terpenes and terpenoids, derivatives and their biotechnological potential are described. This survey aims to highlight the chemical diversity of marine polar life and the versatility of this group of biomolecules, in an effort to encourage further research in drug discovery.

The subtidal red alga Plocamium cartilagineum was collected from the Western Antarctic Peninsula during the 2011 and 2017 austral summers. Bulk collections from specific sites corresponded to chemogroups identified by Young et al. in 2013. One of the chemogroups yielded several known acyclic halogenated monoterpenes (2–5) as well as undescribed compounds of the same class, anverenes B–D (6–8). Examination of another chemogroup yielded an undescribed cyclic halogenated monoterpene anverene E (9) as its major secondary metabolite. Elucidation of structures was achieved through one-dimensional (1D) and 2D nuclear magnetic resonance (NMR) spectroscopy and negative chemical ionization mass spectrometry. Compounds 1–9 show moderate cytotoxicity against cervical cancer (HeLa) cells.

The common Antarctic red alga Plocamium sp. is rich in halogenated monoterpenes with known anticancer and antimicrobial properties and extracts of Plocamium sp. have strong ecological activity in deterring feeding by sympatric herbivores. Plocamium sp. collected near Anvers Island, Antarctica showed a high degree of secondary metabolite diversity between separate individuals. GC/MS results revealed 15 different combinations of metabolites (chemogroups) across individuals, which were apparent at 50% or greater Bray–Curtis similarity and also clearly distinguishable by eye when comparing chromatographic profiles of the secondary metabolomes. Sequencing of the mitochondrial cox1 gene revealed six distinct haplotypes, of which the most common two had been previously reported (now referred to as Haplotypes 1 and 2). With the exception of one individual, three of the chemogroups were only produced by individuals in Haplotype 1. All the other 12 chemogroups were produced by individuals in Haplotype 2, with five of these chemogroups also present in one of the four new, less common haplotypes that only differed from Haplotype 2 by one base pair. The functional relevance of this metabolomic and genetic diversity is unknown, but they could have important ecological and evolutionary ramifications, thus potentially providing a foundation for differential selection.