Identification by using MALDI-TOF mass spectrometry of lactic acid bacteria isolated from non-commercial yogurts in southern Anatolia, Turkey.

Yogurt is a dairy product obtained by bacterial fermentation of milk. Commercial yogurts are produced using standard starters while, in the production of non-commercial yogurt, the microbiota is quite different since yogurts are used as starter for years. To determine the final characteristics of the fermented product it is necessary to know the biochemical properties of the starter cultures, such as acidity, aroma and flavor. This can only be achieved by identifying and characterizing the bacteria in starter cultures. In our study, 208 non-commercial yogurt samples were collected from 9 different locations in Anatolia, southern Turkey. Their pH and lactic acid bacteria profiles were analyzed. Isolated bacteria were identified by MALDI-TOF MS (matrix-assisted laser sesorption-ionization time-of-flight, mass spectrometry), which is a fast and reliable method for identification of bacterial isolates compared to classical laboratory methods. In this study, 41% of the isolates were identified by using this method, which is 99.9% and 34.0% confidence. The isolates contained two genera (Enterococcus and Lactobacillus) and four species. Afterwards, the four lactic acid bacteria were characterized physiologically and biochemically and we found that they differed from lactic acid bacteria used in commercial yogurt production. [Int Microbiol 20(1): 25-30 (2017)].

Identification by using MALDI-TOF mass spectrometry of lactic acid bacteria isolated from non-commercial yogurts in southern Anatolia, Turkey

Yogurt is a dairy product obtained by bacterial fermentation of milk. Commercial yogurts are produced using standard starters while, in the production of non-commercial yogurt, the microbiota is quite different since yogurts are used as starter for years. To determine the final characteristics of the fermented product it is necessary to know the biochemical properties of the starter cultures, such as acidity, aroma and flavor. This can only be achieved by identifying and characterizing the bacteria in starter cultures. In our study, 208 non-commercial yogurt samples were collected from 9 different locations in Anatolia, southern Turkey. Their pH and lactic acid bacteria profiles were analyzed. Isolated bacteria were identified by MALDI-TOF MS (matrix-assisted laser sesorption-ionization time-of-flight, mass spectrometry), which is a fast and reliable method for identification of bacterial isolates compared to classical laboratory methods. In this study, 41% of the isolates were identified by using this method, which is 99.9% and 34.0% confidence. The isolates contained two genera (Enterococcus and Lactobacillus) and four species. Afterwards, the four lactic acid bacteria were characterized physiologically and biochemically and we found that they differed from lactic acid bacteria used in commercial yogurt production (AU)

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Normative data for lateral femoral cutaneous nerve SEPs.

AIMS OF THE STUDY: To determine normative values for somatosensory evoked potentials (SEPs) of the lateral femoral cutaneous nerve (LFCN). METHODS: The LFCN was stimulated at two points, one located 1 cm lateral to the midpoint of a line joining the anterior superior iliac spine (ASIS) and the patella (31 subjects), and the other one located 12 cm distal to the ASIS (24 subjects). Recordings were performed at Cz' (2 cm behind Cz)-Fz. RESULTS: Reproducible SEPs were obtained in all but one of the 31 subjects to ASIS-patella midpoint (mean P1 latency: 33.2+/-3.5 ms, mean side-to-side difference: 2.0+/-1.6 ms) and in all but three of the 24 subjects to stimulation 12 cm distal to the ASIS (mean P1 latency: 30.9+/-3.3 ms, mean side-to-side difference: 2.2+/-1.7 ms). CONCLUSIONS: Reliable SEPs can be obtained to LFCN stimulation. It is easier and, therefore, more convenient to stimulate the ASIS-patella midpoint.