Analysis of the ability to form 2-phenylethyl alcohol by Galactomyces geotrichum MK017

Abstract

The aim of the study was to evaluate the ability of Galactomyces geotrichum MK017 for the biosynthesis of 2-phenylethyl alcohol and optimization of the culture medium composition in order to increase the yield of the product. The culture of Galactomyces geotrichum MK017 strain was carried out in the laboratory scale. For isolation of volatiles Solid Phase Microextraction (SPME) has been used. The identification and quantification of aroma compounds produced by examined microflora was determined by gas chromatography and mass spectrometry (GC/MS) system. The results showed that the tested mould Galactomyces geotrichum MK017 shows the potential for the production of 2-phenylethyl alcohol, but also for the synthesis of phenylacetaldehyde, phenylacetic and phenyllactic acids. For the optimization of the 2-phenylethyl alcohol production yield four different medium composition have been tested. The bioprocess of aroma compound production by tested microorganism was the most efficient on the medium composed of sucrose (80 g/l) and L-phenylalanine (21 g/l) and pH value of 5.0. Using this composition in a batch culture of 770 ml volume the highest concentration of 2-phenylethyl alcohol has been obtained – 6 mg/l. At the same time amount of phenylacetaldehyde, phenylacetic acid and phenyllactic acidhas reached 2.2 mg/l, 10.66 mg/l and 32.3 mg/l respectively.