One of the most interesting groups of fatty acid derivates is the group of conjugated fatty acids, from which the most researched are conjugated linoleic acid (CLA) and conjugated linolenic acid (CLNA), which are associated with countless health benefits. Sex pheromone mixture of some insect species, including tobacco horn-worm (Manduca sexta), are typical for the production of uncommon C16 long conjugated fatty acids with two and three conjugated double bonds, as opposed to C18 long CLA and CLNA. In this study, M. sexta desaturases MsexD2 and MsexD3 were expressed in multiple strains of Y. lipolytica with different genotypes. Experiments with supplementation of fatty acid methyl esters into the medium resulted in production of novel fatty acids. Using GCxGC-MS 20 new fatty acids with two or three double bonds were identified. Fatty acids with conjugated or isolated double bonds or combination of both were produced in trace amounts. Results of this study prove that Y. lipolytica is capable of synthesizing C16 conjugated fatty acids. Further genetic optimization of the Y. lipolytica genome and optimization of the fermentation process could lead to increased production of novel fatty acid derivatives with biotechnologically interesting properties.

Among non-conventional yeasts of industrial interest, the dimorphic oleaginous yeast Yarrowia lipolytica appears as one of the most attractive for a large range of white biotechnology applications, from heterologous proteins secretion to cell factories process development. The past, present and potential applications of wild type, traditionally improved or genetically modified Yarrowia lipolytica strains will be resumed, together with the wide array of molecular tools now available to genetically engineer and metabolically remodel this yeast. The present review will also provide a detailed description of Yarrowia lipolytica strains and highlight the natural biodiversity of this yeast, a subject little touched upon in most previous reviews. This work intends to fill this gap by retracing the genealogy of the main Yarrowia lipolytica strains of industrial interest, by illustrating the search for new genetic backgrounds and by providing data about the main publicly available strains in yeast collections worldwide. At last, it will focus on exemplifying how advances in engineering tools can leverage a better biotechnological exploitation of the natural biodiversity of Yarrowia lipolytica and of other yeasts from the Yarrowia clade.

Yarrowia lipolytica is a widely used microorganism in biotechnology since it is capable of producing a wide range of products. A less studied related strain is Y. divulgata, which is also capable of erythritol production in even higher concenctration then most Y. lipolytica wild strains. Thus the aim of this work was to investigate Y. divulgata’s complex utilisation based on erythritol fermentation to establish a Yarrowia based biorefinery in which both the fermentation broth and separated cells are utilised in high-value products. An important parameter of erythritol fermentation is the adequate oxygen level, so the effect of it was investigated in baffled flasks and fermentor as well. Furthermore, we measured the cosmetic applicability of cell lysates and the efficiency of biodetergent produced during erythritol fermentation. The results were showed that Yarrowia divulagata NCAIM 1485 strain could produce relative high amount of erythritol (44.14±1 g/l) under adequate oxygen supply while its cell lysate could exert good skin moisturizing effect. In all cases, the collected samples had emulsification index above 50% of which stability was also high, above 50% even after 24 hours.Therefore, it can be considered as an effective bioemulsifier. In conclusion, the erythritol fermentation of Y. divulgata is suitable for complex utilisation in a biorefinery, since the fermentation broth can be used for isolation of sweetener and bioemulsifier, meanwhile the cells can be processed for cosmetic application as skin moisturizer.

(1) The study using the quails of the Manchurian golden breed was aimed at the efficacy of the food supplement based on micro-incapsulated phytase of Obessumbacterium proteus in the recombinant yeast producer Yarrowia lipolytica at a dose of 500 FYT/kg of the feed. (2) The effect of the supplement in the poultry diets on the productivity of young and adult quails was assayed; (3) It was found that the keeping the quails on the diets using the microencapsulated phytase O. proteus provided the highest live weight, the highest intensity of egg production, and the slaughter yield of animals, the lowest feed conversion compared to those in control groups and the groups getting a commercial phytase supplement based on Aspergillus ficuum. Taken together the data obtained in our experiments indicate a high degree of assimilation of phytate-containing products by the quails when using the encapsulated phytase compared to both the control and commercial preparation of phytase of the PhyA class. It can be concluded that it is a highly expedient and promising supplement based on the microencapsulated phytase of class D for feeding, which shows the best kinetic features compared to the phytases of PhyA and PhyC classes when working in the chyme of the poultry.