PSEUDOMONAS FLUORESCENS IN SHEEP MILK GREEK YOGHURT FROM VLASINA – A BIOCHEMICAL CHARACTERIZATION
DOI:
https://doi.org/10.35120/kij5403421tKeywords:
Pseudomonas fluorescens, sheep milk greek yoghurt, ID 32 GN, biochemical characterizationAbstract
Pseudomonas fluorescens is an aerobic, rod-shaped, non-sporulating gram-negative bacteria, mostly
found in soil, decaying organic matter and feces. This species contaminates the milk mainly through animal feed
dust, silage, utensils and polluted water. In addition to casein digestion, this psychotropic and lipolytic species
generates butyric and caproic acids by fermentation of milk fat, which release a strong unpleasant odor and give a
rancid and bitter taste to dairy products. In this study we tested 48 hours old sheep's sour milk, produced in a
household in Vlasina, southeastern Serbia, using traditional method. Standard bacteriological protocols were used
for isolation and identification Pseudomonas fluorescens strains. Biochemical identification was performed using
the commercial API 32GN E system, and 60473057073 profile was obtained (Pseudomonas fluorescens, %Id=99.5
and T=0.74). Positive biochemical tests were: N-acetyl-glukosamine (NAG), D-Ribose (RIB), Sodium malonate
(MNT), Sodium acetate (ACE), Lactic acid (LAT), L-Alanine (ALA), D-Mannitol (MAN), D-Glucose (GLU), LArabinose
(ARA), Capric acid (CAP), Valeric acid (VALT), Trisodium citrate (CIT), L-Histidine (HIS), Potasium
2-ketogluconate (2KG), 3-Hydroxybutyric acid (3OBU), 4-Hydroxybenzoic acid (pOBE), L-Serine (SER), LProline
(PRO) and Oxidase (OX). Negative biochemical tests were: L-Rhamnose (RHA), Inositol (INO), DSaccharose
(SAC), D-Maltose (MAL), Itaconic acid (ITA), Suberic acid (SUB), Salicin (SAL), D-Melibose (MEL),
L-Fucose (FUC), D-Sorbitol (SOR), Propionic acid (PROP), Potasium 5-ketogluconate (5KG), Glycogen (GLYG)
and 3-hydroxybenzoic acid (mOBE). Based on the example of the strain Pseudomonas fluorescens, the API ID 32
GN system proved to be precise and very efficient in the identification of this lipolytic type. Given that
pasteurization and cooling processes do not entirely inhibit the enzym activity and growth of this psychotrophic
bacteria, informing individual milk and milk product manufacturers in the Vlasina region about good manufacturing
practices would limit contamination and bacteriological deterioration.
References
Birollo, G. A., Reinheimer, J. A., & Vinderola, C. G. (2001). Enterococci vs non-lactic acid microflora as hygiene indicators for sweetened yoghurt. Food Microbiology, 18(6), 597-604.
Dechemi, S., Benjelloun, H., & Lebeault, J. M. (2005). Effect of modified atmospheres on the growth and extracellular enzyme activities of psychrotrophs in raw milk. Engineering in life sciences, 5(4), 350-356.
Hervert, C. J., Alles, A. S., Martin, N. H., Boor, K. J., & Wiedmann, M. (2016). Evaluation of different methods to detect microbial hygiene indicators relevant in the dairy industry. Journal of dairy science, 99(9), 7033-7042.
Hervert, C. J., Martin, N. H., Boor, K. J., & Wiedmann, M. (2017). Survival and detection of coliforms, Enterobacteriaceae, and gram-negative bacteria in Greek yogurt. Journal of Dairy Science, 100(2), 950-960.
Canganella, F., Nespica, M. L., Giontella, D., & Trovatelli, L. D. (1999). Survival of Enterobacter cloacae and Pseudomonas paucimobilis in yoghurts manufactured from cow's milk and soymilk during storage at different temperatures. Microbiological research, 154(1), 15-21
Davidson, P. M. (2004). Coliform and other indicator bacteria. Standard methods for the examination of dairy products, 187-226.
El-Mokhtar, M. A., Hassanein, K. M., Ahmed, A. S., Gad, G. F., Amin, M. M., & Hassanein, O. F. (2020). Antagonistic activities of cell-free supernatants of lactobacilli against extended-spectrum β-lactamase producing Klebsiella pneumoniae and Pseudomonas aeruginosa. Infection and Drug Resistance, 13, 543.
Maske, B. L., Pereira, G. V. D. M., CARVALHO NETO, D. P. D., Lindner, J. D. D., Letti, L. A. J., Pagnoncelli, M. G., & Soccol, C. R. (2020). Presence and persistence of Pseudomonas sp. during Caspian Sea-style spontaneous milk fermentation highlights the importance of safety and regulatory concerns for traditional and ethnic foods. Food Science and Technology, 41, 273-283.
Martins, M. L., Pinto, U. M., Riedel, K., & Vanetti, M. C. (2015). Milk-deteriorating exoenzymes from Pseudomonas fluorescens 041 isolated from refrigerated raw milk. Brazilian Journal of Microbiology, 46, 207-217.
Martin, N. H., Carey, N. R., Murphy, S. C., Wiedmann, M., & Boor, K. J. (2012). A decade of improvement: New York State fluid milk quality. Journal of dairy science, 95(12), 7384-7390.
Masiello, S. N., Martin, N. H., Trmčić, A., Wiedmann, M., & Boor, K. J. (2016). Identification and characterization of psychrotolerant coliform bacteria isolated from pasteurized fluid milk. Journal of Dairy Science, 99(1), 130-140.
Mohapatra, A., Shinde, A. K., & Singh, R. (2019). Sheep milk: A pertinent functional food. Small ruminant research, 181, 6-11.
Monget, D., Freney, J., BOEUFTRAS, J., Desmonceaux, M., Guicherd, M., & Ponchon, S. (1985). Nouveaux systèmes d'identification des bacilles à gram négatif utilisant des tests d'assimilation: API 20 NE et ATB 32 GN. Innovation et technologie en biologie et médecine, 6(2), 228-235.
Reynaud, A. E., Coude du Foresto, B., & Courtieu, A. L. (1988). Etude comparative de diverses galeries API pour l'identification des bactéries à Gram négatif. In Annales de biologie clinique (Paris) (Vol. 46, No. 4, pp. 259-262).
Tasić, S., Tasić, N., (2021): Biochemical characterization of Enterobacter cloacae from sheep cheese, VII International Congress ”Engineering, Environment and Materials in Process Industry EEM2021”, Book of abstracts, Jahorina, March 17-19, 2021, p. 121.
Tumbarski, Y. D., Yanakieva, V. B., Denkova-Kostova, R. S., & Denkova, Z. R. (2021). ISOLATION, IDENTIFICATION AND COMPARISON OF SOME PROPERTIES OF LACTOBACILLUS DELBRUECKII SUBSP. BULGARICUS STRAINS FROM TRADITIONAL BULGARIAN AND ITALIAN YOGURTS. Carpathian Journal of Food Science & Technology, 13(1).
Yerlikaya, O., Saygili, D., & Akpinar, A. (2020). Evaluation of antimicrobial activity and antibiotic susceptibility profiles of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains isolated from commercial yoghurt starter cultures. Food Science and Technology, 41, 418-425.
