Traditional fermented foods are the best source for the isolation of strains with specific traits to act as functional starters and to keep the biodiversity of the culture collections. Besides, these strains could be used in the formulation of foods claimed to promote health benefits, i.e. those containing probiotic microorganisms. For the rational selection of strains acting as probiotics, several in vitro tests have been proposed. In the current study, we have characterized the probiotic potential of the strain Lactobacillus paraplantarum BGCG11, isolated from a Serbian soft, white, homemade cheese, which is able to produce a "ropy" exopolysaccharide (EPS). Three novobiocin derivative strains, which have lost the ropy phenotype, were characterized as well in order to determine the putative role of the EPS in the probiotic potential. Under chemically gastrointestinal conditions, all strains were able to survive around 1-2% (10(6)-10(7)cfu/ml cultivable bacteria) only when they were included in a food matrix (1% skimmed milk). The strains were more resistant to acid conditions than to bile salts and gastric or pancreatic enzymes, which could be due to a pre-adaptation of the parental strain to acidic conditions in the cheese habitat. The ropy EPS did not improve the survival of the producing strain. On the contrary, the presence of an EPS layer surrounding the strain BGCG11 hindered its adhesion to the three epithelial intestinal cell lines tested, since the adhesion of the three non-ropy derivatives was higher than the parental one and also than that of the reference strain Lactobacillus rhamnosus GG. Aiming to propose a potential target application of these strains as probiotics, the cytokine production of peripheral blood mononuclear cells (PBMC) was analyzed. The EPS-producing L. paraplantarum BGCG11 strain showed an anti-inflammatory or immunosuppressor profile whereas the non-ropy derivative strains induced higher pro-inflammatory response. In addition, when PBMC were stimulated with increasing concentrations of the purified ropy EPS (1, 10 and 100μg/ml) the cytokine profile was similar to that obtained with the EPS-producing lactobacilli, therefore pointing to a putative role of this biopolymer in its immune response.

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This study was focussed on a comprehensive investigation on the state of pollution of the Danube and Sava Rivers in the region of Belgrade. Different complementary analytical approaches were employed covering both i) organic contaminants in the river water by target analyses of hormones and neonicotinoids as well as non-target screening analyses and ii) heavy metals in the sediments. Finally, some common water quality parameters were analysed. The overall state of pollution is on a moderate level. Bulk parameters did not reveal any unusual observations. Moreover, quantification of preselected organic contaminants did not indicate to elevated pollution. More significant contaminations were registered for chromium, nickel, zinc and partially copper in sediments with values above the target values according to Serbian regulations. Lastly, non-target screening analysis revealed a wider spectrum of organic contaminants comprising pharmaceuticals, technical additives, personal care products and pesticides. The study presented a comprehensive view on the state of pollution of the Sava and Danube Rivers and is the base for setting up further monitoring programs. As a superior outcome, it was illustrated how different chemical analyses can result in different assessments of the river quality. A

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Eighty-one strains of lactic acid bacteria (LAB) were isolated from white semi-hard homemade cheese, designated Zlatar BGNV, which was taken from household settled on Northern side of mountain Zlatar. The Zlatar BGNV cheese was manufactured from raw cow's milk without addition of the starter culture. All isolates of LAB were characterized by phenotypic and genotypic tests. Identification of strains was done by the repetitive extragenic palindromic-polymerase chain reaction (rep-PCR) with (GTG)5 primer and 16S rDNA sequence analysis. The most present species in Zlatar BGNV cheese were Lactobacillus casei/paracasei (65.43%) and Enterococcus faecalis (29.63%). Two facultative heterofermentative rods were identified as Lactobacillus plantarum (2.47%), and two obligate hetrofermentative LAB isolates as Lactobacillus parabuchneri (2.47%). Among all 81 tested isolates, only eight enterococci were producers of antimicrobial compounds. Fourteen of 16 tested lactobacilli isolates showed medium to very good proteolytic activity. All 57 lactobacilli from the Zlatar BGNV cheese curdled milk very slowly or did not curdle milk at all. However, three isolates of enterococci, BGNV1-63, BGNV1-76 and BGNV1-80, showed very good activity in milk and curdled milk within 5 h. They showed very high proteolytic activity hydrolyzing completely αs1- and κ-casein after 3 h, and β-casein after 30 min of incubation. In addition, those three enterococcal isolates degraded gelatin. Comparing obtained results with those previously achieved in examination of LAB microflora in another Zlatar BGZLS cheese made also from raw cow's milk, it can be concluded that LAB microflora in the Zlatar BGNV cheese is less diverse