As represented by fermentation production of arachidonic acid-rich oil, Mortierella alpina 1S-4 has a high potential in production of polyunsaturated fatty acid-rich oils, and various breeding researches have been performed. In this article, we reviewed the development of transformation systems for the M. alpina 1S-4 and summarized the recent molecular breeding researches on the fermentative production of omega-3 eicosapentaenoic acid (EPA, 20: 5n-3). Furthermore, the development of useful promoters and gene targeting systems and their application to the production of various PUFA-rich oils were also described.

Omega-3 polyunsaturated fatty acids (ω3-PUFAs) have attracted attention because of their unique physiological function. The considerable abundances of eicosapentaenoic acid, docosahexaenoic acid, and α-linolenic acid in nature made possible the studies on their bioactivities. On the other hand, there are few reports on the other ω3-PUFAs, such as stearidonic acid, ω3-eicosatetraenoic acid and ω3-docosapentaenoic acid (ω3-DPA), because their supply has been limited to date. These minor ω3-PUFAs have been expected to possess beneficial function as precursors of bioactive substances as well as DHA and so on. Therefore, sufficient supply of such rare PUFAs has been required for elucidation of their physiological function.

ω3-DPA has been reported to be present in several natural oils obtained from harp seal and so on, but the content of ω3-DPA was no more than 5 % in total fatty acids. Thus, recent investigations have focused on ω3-PUFAs production by alternative source such as oleaginous microbes, fungi, plants and microalgae. In particular, we focused on Labyrinthulea, one of representative oleaginous microbes, as stable and rich source of ω3-DPA. In this paper, we introduce the study of production of ω3-DPA by isolated Labyrinthulea, Aurantiochytrium sp. T7.

For conservation of the global environment with the recycling of resources and energy, a novel sustainable biorefinery system has been developed to produce useful lipids such as polyunsaturated fatty acids, carotenoids, and hydrocarbons from marine macroalgae and thermal power generation exhaust gas. To maximize the productivity, a two-stage fermentation system was constructed using oleagenous Labyrinthulean protist, genus Auranthiochytrium, assimilating organic acids, which was tried to further functionalize by genome breeding technologies.

Polyunsaturated fatty acids (PUFA), such as eicosapentaenoic acid (EPA), are known to have various physiological activity. The availability of PUFA is currently limited because they are mainly produced from fish oil, and a sustainable source of PUFA is needed. Microalgae have attracted attention as an alternative source of PUFA due to their high lipid productivity. Although several studies on algae cultivation, extraction and purification of lipid have been ongoing, low productivity of PUFA has been a problem for commercial use of microalgae. This review summarizes recent research on elucidation of EPA synthetic pathway and improvement of EPA productivity of microalgae Nannochloropsis.

In the pharmaceutical and health science area, transdermal drug delivery is a very important research and development area. Generally, skin is a barrier that protects the body from the outside. Generally, the properties of compounds that are advantageous for transdermal absorption are low molecular weight (<500 da) and high lipophilicity (octanol/water partition coefficients is about 1 to 2). Therefore, the skin permeability of the water-soluble compound is very low. However, consumers want to administer from the skin. In this article, the author described a novel technique for enhancement of percutaneous absorption of hyaluronic acid as a model of a water-soluble and high molecular weight compound. Specifically, hyaluronic acid nanoparticles (HANP) were prepared by the poly ion complex method. As a result, HANP was able to deliver HA into the skin by passive diffusion. I hope that these technologies can contribute to pharmaceutical and health science in the future.