Effect of Culture Conditions on Fatty Acid Profiles of Bacteria and Lipopolysaccharides of the Genus Pseudomonas—GC-MS Analysis on Ionic Liquid-Based Column

The profiling of bacterial fatty acids is a well-established technique in identifying and classifying bacteria. Cultivation conditions may affect the biosynthesis, thereby, changing the fatty acid profile in bacteria. The effect of the culture conditions on the fatty acid components of Pseudomonas aeruginosa PAO1, Pseudomonas aeruginosa ATCC 27853, Pseudomonas aeruginosa polyresistant and Pseudomonas putida all are aligned to the genus Pseudomonas. The fatty acids in the lipopolysaccharides of Pseudomonas aeruginosa PAO1 were also examined. The effects of the cultivation conditions were followed by using agar and blood agar media at the characteristic temperatures, 25 °C, 37 °C and 42 °C, respectively, and an analysis was made during the 1st, 3rd and 5th day following inoculation. In addition to quantitative differences, we also experienced qualitative differences in the fatty acid profiles which detect newly appearing fatty acids, due to changes in environmental factors. The application of ionic liquid-based column unveils new possibilities for the analyses of fatty acids in GC-MS experiments for bacterial fatty acid profiling. The validation results (response linearity, limit of detection, limit of quantification, system suitability, intraday and interday repeatability and accuracy) show the high separation efficiency of the ionic liquid-based column in the analyses

Microfluidic Analysis for the Determination of Protein Content in Different Types of Plant-Based Drinks

The widespread consumption of plant-based drinks, driven by health and dietary reasons (including cow’s milk allergy, lactose intolerance, milk protein intolerance, following a vegetarian or vegan diet) necessitates automated and accurate test methods. Our study demonstrates the simultaneous determination of protein components and total protein concentrations in plant-based milk alternatives using a rapid and reproducible microchip gel electrophoretic method. As expected, the electrophoretic profiles of each plant-based drink differed. Based on our analyses and statistical evaluation, it can be determined that the protein profiles of different plant-based beverages do not differ significantly between different manufacturers or different expiry dates. The measured total protein content was compared with the nominal values, i.e., the values stated on the beverage labels. As the number of consumers of functional and specialized plant-based milk alternatives continues to rise, it is important to prioritize methods that provide qualitative and quantitative information on protein composition and other nutrients