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Mucoromycota fungi possess a versatile metabolism and can utilize various substrates for production of industrially important products, such as lipids, chitin/chitosan, polyphosphates, pigments, alcohols and organic acids. However, as far as commercialisation is concerned, establishing industrial biotechnological processes based on Mucoromycota fungi is still challenging due to the high production costs compared to the final product value. Therefore, the development of co-production concept is highly desired since more than one valuable product could be produced at the time and the process has a potentially higher viability. To develop such biotechnological strategy, we applied a high throughput approach consisting of micro-titre cultivation and FTIR spectroscopy. This approach allows single-step biochemical fingerprinting of either fungal biomass or growth media without tedious extraction of metabolites. The influence of two types of nitrogen sources and different levels of inorganic phosphorus on the co-production of lipids, chitin/chitosan and polyphosphates for nine different oleaginous Mucoromycota fungi was evaluated. FTIR analysis of biochemical composition of Mucoromycota fungi and biomass yield showed that variation in inorganic phosphorus had higher effect when inorganic nitrogen source-ammonium sulphate-was used. It was observed that: (1) Umbelopsis vinacea reached almost double biomass yield compared to other strains when yeast extract was used as nitrogen source while phosphorus limitation had little effect on the biomass yield; (2) Mucor circinelloides, Rhizopus stolonifer, Amylomyces rouxii, Absidia glauca and Lichtheimia corymbifera overproduced chitin/ chitosan under the low pH caused by the limitation of inorganic phosphorus; (3) Mucor circinelloides, Amylomyces rouxii, Rhizopus stolonifer and Absidia glauca were able to store polyphosphates in addition to lipids when high concentration of inorganic phosphorus was used; (4) the biomass and lipid yield of high-value lipid producers Mortierella alpina and Mortierella hyalina were significantly increased when high concentrations of inorganic phosphorus were combined with ammonium sulphate, while the same amount of inorganic phosphorus combined with yeast extract showed negative impact on the growth and lipid accumulation. FTIR spectroscopy revealed the co-production potential of several

The aim of this work was to compare the methods of malondialdehyde detection, as the main secondary product of the lipid peroxidation process, in meat and meat products. Malondialdehyde measurements were performed by two modified methods, the 2-thiobarbituric acid spectrophotometric method and the reverse-phase high-performance liquid chromatography in raw, mechanically-deboned chicken meat and in manufactured frankfurters. The malondialdehyde concentrations measured by the 2-thiobarbituric acid spectrophotometric method were found to be overestimated by more than 25% in raw meat and more than 27% in frankfurters in comparison to the results of reverse-phase high-performance liquid chromatography (p < 0.05). The achieved results showed that the presented modified reverse-phase high-performance liquid chromatography method was more applicable and more accurate for the quantification of malondialdehyde in samples of meat and meat products.

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Yarrowia lipolytica is a promising platform for single cell oil production. It is well-known for its metabolism oriented toward utilization of hydrophobic substrates and accumulation of storage lipids. Multiple copies of DGA2 under constitutive promoter were introduced into the Q4 strain, a quadruple mutant deleted for the four acyltransferases (Δdga1, Δdga2, Δlro1, and Δare1) to improve lipid accumulation. The Q4-DGA2 x3 strain contains three copies of DGA2. Further increase in accumulation was accomplished by blocking the β-oxidation pathway through MFE1 gene deletion yielding Q4-Δmfe DGA2 x3. In order to use molasses as a substrate for single cell oil production, sucrose utilization was established by expressing the Saccharomyces cerevisiae SUC2 gene yielding Q4-SUC2 DGA2 x3 and Q4-Δmfe SUC2 DGA2 x3. During cultivation on sucrose medium with a carbon to nitrogen ratio of 80, both strains accumulated more than 40 % of lipids, which was a 2-fold increase in lipid storage. Q4-Δmfe SUC2 DGA2 x3 accumulated more lipids than Q4-SUC2 DGA2 x3 (49 vs. 43 %) but yielded less biomass (13.7 vs. 15 g/L). When grown on 8 % (v/v) molasses, both strains accumulated more than 30 % of lipids after 3 days, while biomass yield was higher in Q4-SUC2 DGA2 x3 (16.4 vs. 14.4 g/L). Further addition of molasses at 72 h resulted in higher biomass yield, 26.6 g/L for Q4-SUC2 DGA2 x3, without modification of lipid content. This work presents genetically modified strains of Y. lipolytica as suitable tools for direct conversion of industrial molasses into value added products based on single cell oils.

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