Evaluation of Biogenic Amines Formation by Proteolytic Enterococci Strains Isolated From Raw Dromedary Milks From Southern Algeria

Abstract

Twenty-three strains of lactic acid enterococci isolated from dromedary raw milks in Southern Algeria were investigated for their proteolytic activity and ability to produce biogenic amines by decarboxylating amino acids: histidine, tyrosine and ornithine. All strains tested displayed proteolytic activities, but none of them were able to produce detectable biogenic amines in the usual adequate laboratory media, namely, Joosten and Northolt medium and Leuschner medium. Polymerase chain reaction experiments indicate a positive correlation between the absence of the hdc and odc genes and the lack of histamine and putrescine production for all tested strains. By contrast, all strains appeared to possess tdc gene, but no correlation was found with a negative expression of tyrosine decarboxylase. PRACTICAL APPLICATIONSIn foods, biogenic amines are mainly generated by decarboxylation of the corresponding amino acids through substrate-specific enzymes of the microorganisms present in this environment, particularly histidine, tyrosine, lysine, ornithine and arginine, and the capability of enterococci and some other lactic acid bacteria to produce biogenic amines has been described. For this purpose, several qualitative and quantitative methods to determine biogenic amines production by these microorganisms have been developed. There is great interest to identify and to characterize the bacteria strains intended for an industrial use and to verify if they are potentially able to produce biogenic amines in order to prevent it's synthesis and limit the poisoning risk.

Biogenic amine formation and bacterial contribution in Natto products

“…In addition, the average pH value observed was found to be slightly higher than that (4.9-7.3) reported previously by Tsai et al (2007). Since the optimum pH for biogenic amine production is slightly acidic (Hassaïne, Zadi-Karam, & Karam, 2009), however, it seems clear that there may be no apparent relationships among the data, including the amounts of biogenic amines and pH values, obtained in the present and previous studies. Thus, together with the fact that Natto is usually produced by fermentation within a 1-day period, and shipped and stored at freezing temperatures until consumed, it can be suggested that the large variations of biogenic amine contents in Natto products might be poorly influenced by the physicochemical properties, such as pH and water activity.…”

Investigating the biotechnological potential of lactic acid bacteria strains isolated from different Algerian dairy and farm sources

“…paracasei LGM31, LGM32, LGM35 showed a faster and stronger acidification ability, higher than that reported for others Algerian milk isolates (Bousmahamarroki et al 2015). This capacity is crucial in cheese production, since a rapid acidification favours the coagulation and limits the growth of adventitious undesired microorganisms (Hassaïne et al 2007).…”

Molecular identification of non-lactic acid bacteria isolated on MRS medium and associated to the production of biogenic amines in adjuevan, a fermented fish of Côte d’Ivoire

“…DNA extraction was carried out according to the method of Hassaïne et al [11]. Bacteria strains stored at −20° C were inoculated into nutriment broth (1.5 mL) for overnight incubation.…”