Skye Robin Thomas-Hall

The EPA-rich marine microalga Nannochloropsis oceanica provides insight into EPA biosynthesis via the characterized Δ6-desaturase pathway, positioning this microalga for both experimental research and sustainable production solutions for non-fish oil-derived EPA oils. This review constructs a comprehensive molecular-to-clinical framework demonstrating how the chemical structure of eicosapentaenoic acid (EPA) determines its biological activities, i.e., the specific positioning of the Δ17 double bond governs competitive enzymatic metabolism with arachidonic acid (ARA), yielding attenuated 3-series and 5-series eicosanoids while uniquely enabling E-series resolvin biosynthesis. Metabolic pathway modulation (AMPK, NF-κB, and SREBP-1c) translate biochemical events into transcriptional reprogramming. Sustained alterations in gene expression, membrane composition, and inflammatory mediator profiles manifest as clinical benefits across cardiovascular disease, metabolic disorders, inflammatory conditions, and psychiatric illnesses. The pleiotropic nature of EPA effectssimultaneously anti-inflammatory, TAG-lowering, anti-arrhythmic, insulin-sensitizing, and pro-resolving — arises not from independent mechanisms but from coordinated, multi-level integration. The ARA:EPA ratio emerges as the unifying quantitative biomarker, integrating dietary intake, competitive membrane incorporation, eicosanoid biosynthetic balance, and tissue-level inflammatory tone into a single metric predictive of disease risk and therapeutic response. Lowering this ratio through EPA supplementation represents a systems-level intervention: simultaneously reducing pro-inflammatory mediator production, enhancing resolution capacity, improving metabolic flexibility, and stabilizing cellular energetics.

Worldwide glaciers are annually retreating due to global overheating and this phenomenon determines the potential lost of microbial diversity represented by psychrophilic microbial population sharing these peculiar habitats. In this context, yeast strains, all unable to grow above 20°C, consisting of 42 strains from Antarctic soil and 14 strains isolated from Alpine Glacier, were isolated and grouped together based on similar morphological and physiological characteristics. Sequences of the D1/D2 and ITS regions of the ribosomal DNA confirmed the previous analyses and demonstrated that the strains belong to unknown species. Three new species are proposed: Mrakia robertii sp. nov. (type strain CBS 8912), Mrakia blollopis sp. nov. (type strain CBS 8921) and a related anamorphic species Mrakiella niccombsii sp. nov. (type strain CBS 8917). Phylogenetic analysis of the ITS region revealed that the new proposed species were closely related to each other within the Mrakia clade in the order Cystofilobasidiales, class Tremellomycetes. The Mrakia clade now contains 8 sub-clades. Teliospores were observed in all strains except CBS 8918 and for the Mrakiella niccombsii strains.