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This study aimed to assess the safety and antimicrobial properties of Enterococcus species isolated from raw goat milk and cheese. The isolates were evaluated for hemolytic activity on blood agar plates and antibiotic susceptibility by determining the minimum inhibitory concentrations (MICs) of five antibiotics: ampicillin, tetracycline, gentamicin, streptomycin, and vancomycin. Furthermore, the antagonistic activity of the Enterococcus strains against indicator bacteria was assessed using the agar-well diffusion method. Hemolytic activity results demonstrated a-hemolysis in all isolates. Among the 71 Enterococcus isolates examined, 32.39% exhibited resistance to at least one antibiotic, with resistance profiles varying between species. Enterococcus faecalis isolates predominantly showed resistance to vancomycin, ampicillin, tetracycline, and gentamicin, while Enterococcus faecium and Enterococcus hirae displayed resistance to vancomycin with different susceptibility patterns to the other antibiotics. The antagonistic assays revealed a broad spectrum of inhibitory effects, with variation in inhibition zone diameters. These findings provide valuable insights into the safety and antimicrobial potential of Enterococcus spp. from raw goat milk and cheese and give an insight into their potential applications in the food industry.

This study investigates the community of coagulase-negative staphylococci (CNS) in samples of Sjenica sheep's ham from different villages across three seasons over a 120-day maturation period. The CNS group was identified into five distinct species: Staphylococcus epidermidis, S. saprophyticus, S. carnosus, S. xylosus, and S. equorum. The safety evaluation revealed no hemolytic activity in any tested isolates, while resistance to novobiocin was observed in S. xylosus and S. saprophyticus isolates. The technological properties of the isolated CNS were assessed, including tolerance to different temperatures, pH values, salt concentrations, as well as proteolytic and lipolytic activity. Results demonstrated the ability of all tested isolates to grow across various pH values and salt concentrations, with isolates of S. carnosus and S. epidermidis showing tolerance to 45°C. The best technological properties were shown by S. carnosus, followed by S. equorum. These findings provide insights into the potential applications of CNS in food processing industries, as putative starters.

The aim of this study was to determine the antifungal activity of extracts and isolated substances from the root of Onosma visianii Clem. (Boraginaceae) by determining the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). The results show that antifungal activity depends on species of microorganism and the type of substances or extracts. All tested substances showed selective and moderate antifungal activity. MIC and MFC values for the extracts ranged from

Nine species (sixteen isolates) of lactic acid bacteria (LAB) isolated from traditionally made Serbian cheese were evaluated for their enzymatic activities in order to select indigenous strains of technical interest for the manufacture of cheese. These strains were selected based on their previously determined biochemical and physiological characteristics, as well as their antimicrobial activity, and were identified as Lactococcus lactis subsp. lactis (one isolate), Lc. lactis subsp. lactis biovar. diacetylactis (five isolates), Lactobacillus fermentum (two isolates), Lb. plantarum (one isolate), Lb. brevis (one isolate), Enterococcus faecalis (three isolates), E. faecium (one isolate), E. durans (one isolate) and E. hirae (one isolate). The enzymatic activities (acid and alkaline invertases, alkaline phosphatase, alkaline protease, a-amylase) were measured by using the spectrophotometric method. The results indicated that all Lactobacillus isolates showed protease, amylase, and alkaline phosphatase activities, while the activities of acid and alkaline invertases were not observed. The Lactococcus isolates showed protease, acid invertase and alkaline phosphatase activities, except the KGPMF50 isolate, which showed no alkaline phosphatase activity. The tested Enterococcus isolates showed weakly and strain-specific enzymatic activity. The results indicated that the enzymes produced by the investigated strains have a role in the formation of the specific flavor of cheese and that these isolates, especially Lactobacillus isolates, showed the potential for use in the dairy industry or applied biotechnology.

In this paper, the effect of different temperatures, pH, and NaCl concentration on the growth of autochthonous lactic acid bacteria isolated from traditionally made Serbian cheese (Sokobanja area) was investigated by using the spectrophotometric method. Growth of tested Lactobacillus (Lb. fermentum, Lb. plantarum, and Lb. brevis) and Lactococcus lactis subsp. lactis biovar. diacetylactis five isolates were better in acidic pH, while the growth of Enterococcus isolates (E. durans, E. faecium, and E. faecalis) was better in basic pH, at 37 °C. At 4 °C after 24 h, none of the tested bacteria showed growth. Since the autochthonous isolates were tolerant to a tested range of dairy processing conditions, further studies need to include the characterization of enzymatic activity of selected isolates, as well as the ability to use these isolates like starter cultures or food supplements in dairy or non-dairy products.

In this paper, we investigated, for the first time, the enzyme activity of enterobacteria from cheese from Southeastern Serbia (Sokobanja), which was produced in a traditional way. The tested bacteria were selected from the spring, summer, and autumn collections and grown in two different broths. The enzyme activity was investigated in the two broths and measured using spectrophotometry method. It was concluded that there were differences in the amount of extracellular enzymes depending on the broths. A statistically significant rise in the amount of enzymes was demonstrated in Tripton soy broth. Bacteria in cheese do not possess the ability to produce extracellular enzymes in large amounts. Therefore, they do not change the organoleptic characteristics of the cheese. There is a possibility that if they are found outside their natural environment (cheese), without interactions with antagonists, they may exhibit stronger enzyme activity.

The purpose of this study was the investigation of the growth ability of lactic acid bacteria (LAB), isolated from traditionally made cheese from Southeastern Serbia, in the presence of different percent of sugars and sugar substitutes (fructose, lactose, inulin, and mannitol). Dextrose was included for comparative purposes. The results indicated that fructose and lactose stimulated the growth of Lactobacillus strains, with exceptions of Lactobacillus plantarum KGPMF62 and Lb. plantarum LP 299v. Lactose showed similar effects like dextrose on the growth of Lactococcus strains, while higher growth rates of Enterococcus hirae KGPMF9, E. durans KGPMF10, E. faecium KGPMF14, and E. faecalis KGPMF47 were observed for lactose and mannitol. The results indicated the potential use of tested sugars and sugar substitutes as prebiotic compounds for the development of symbiotics with tested LAB, in medical or food industry.

This study observed the preliminary investigation of Oleum Hyperici, an original product made from Hypericum perforatum flowers, collected from Goč Mountain (Serbia). Some of the chemical properties (pH, the content of metals and metalloids - As, Cr, Pb, Cd, Ni, Hg) and the microbiological safety of the product including the total count of aerobic mesophilic bacteria, coagulase positive staphylococci, Escherichia coli, Pseudomonas aeruginosa, Proteus sp., as well as fungi: molds and yeasts) were evaluated. Antimicrobial activity of H. perforatum oil against 18 species of bacteria was determined using the disc diffusion and microdilution methods, by determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The antibiofilm activity of Oleum Hyperici was evaluated using the biofilm formation assay. The results indicated that oil did not contain potentially pathogenic microorganisms. Oleum Hyperici product showed the antimicrobial activity on the most of tested bacteria (inhibition zone was in a range from 14 - 24 mm), except on Klebsiella pneumoniae ATCC 70063, K. pneumoniae, E. coli ATCC 25922, P. mirabilis, Bacillus subtilis ATCC 6633 and B. subtilis IP 5832. According to the obtained results, tested bacteria (planktonic and biofilm form) showed sensitivity up to 10-2 dilution of Oleum Hyperici. Based on the obtained preliminary results, it could be concluded that Oleum Hyperici can be used in traditional medicine for development control of some potential human pathogens.

This study aimed to unleash the potential of indigenous lactic acid bacteria (LAB) originating from traditionally made Serbian goat cheese. Following the isolation and identification of the LAB, the safety aspects of the isolates were evaluated through tests for hemolytic activity and antibiotic sensitivity. The selected isolates were then tested for various technological properties, including growth in methylene blue, proteolytic activity, acidification, curd formation ability in both pure and enriched goat milk, diacetyl production, antagonistic potential against other LAB, and biofilm formation ability. The results indicated that Lactococcus spp., Lacticaseibacillus spp., and Lactiplantibacillus spp. did not exhibit α or β hemolysis, while enterococci displayed α hemolysis. A higher number of isolates demonstrated sensitivity to ampicillin, tetracycline, and streptomycin, while sensitivity to gentamicin and vancomycin was strain-dependent. Based on the evaluation of technological properties, Lacticaseibacillus paracasei M-1 and Lactiplantibacillus plantarum C7-7, C7-8, and C14-5 showed promising characteristics. Additionally, Lactococcus lactis subsp. lactis strains C0-14 and C21-8 emerged as promising candidates with notable technological properties. Notably, certain indigenous strains LAB exhibit promising technological properties and safety profiles. These characteristics make them suitable candidates for use as starter or adjunct cultures in goat's milk cheese production, potentially enhancing the quality and safety of the cheese as well as hygiene practices among small-scale dairy producers. [ABSTRACT FROM AUTHOR]

In this research paper, the total phenols (TP), flavonoids (TF), and tannins (TT) content in the acetone and ethyl acetate extracts of Najas marina L. and the identification and quantification of phenolic acids and flavonoids from the ethyl acetate extract were performed. Antioxidant, antimicrobial, and antibiofilm properties of the mentioned extracts were investigated in vitro. The genotoxic potential was analyzed in cultured human peripheral blood lymphocytes (PBL). The TP and TF content was higher in the ethyl acetate extract, dominated by quercetin (172.4 µg mg−1) and ferulic acid (22.74 µg mg−1), while the TT content was slightly higher in the acetone extract. Both extracts tested showed limited antioxidant effects compared to ascorbic acid. The strongest antibacterial activity was observed with Gram-positive bacteria, particularly Staphylococcus aureus (MIC and MMC at 0.31 mg ml−1) and S. aureus ATCC 25923 (MIC at <0.02 mg ml−1), while antifungal activity was limited. Both extracts tested showed better activity on preformed biofilms. Acetone extract had no genotoxic activity but showed significant genoprotective activity against mitomycin C-induced DNA damage in cultured PBLs. Results of our research demonstrate the potential for the development of plant-based antibacterial and biofilm agents. [ABSTRACT FROM AUTHOR]

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Food Quality / Archiv für Lebensmittelhygiene is the property of Presse Dienstleistungsges. mbH & Co. KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research project aimed to investigate the physico-chemical, sensory, hygienic and safety characteristics of raw goat milk, whey, brine and traditional goat cheese during the ripening period of 28 days. Physico-chemical parameters included the determination of dry matter, fat, ash, protein, pH, water activity and NaCl content. The presence of Enterobacteriaceae and fungi was estimated on milk and cheese samples, and a sensory panel evaluated the products' features and acceptability during ripening. The results show that the cheese under study belongs to the acid full-fat cheese group. A consumer panel attributed high scores to the goat cheese, until the 21st day of ripening. After this period, the overall features altered significantly, including augmented bitterness, odor intensification and the development of molds on the surface. The presence of fungi, associated with Enterobacteriaceae, suggests that the hygiene of the production processes needs to be improved. Regarding microbial safety, the detection of putative pathogens and antibiotic resistances recommend an active surveillance of traditional foods to avoid foodborne infections and/or the dissemination of resistant microorganisms along the food chain. [ABSTRACT FROM AUTHOR]

Wine samples, wine evaporated to dryness, dealcoholized wine and the original shape wine, made from autochthonous grapevine variety from Serbia and Montenegro, were examined in order to determine total phenols, flavonoids and proanthocyanins, as well as their antioxidant activity. Antimicrobial and anti-biofilm activities were evaluated. The grapevine variety Vranac had the best values for total phenols, flavonoids and proanthocyanins compounds. The original shape wine samples showed stronger antioxidative efficiency, with the effective concentration values at which 50% of 2,2-diphenyl-1-picrylhydrazyl radicals were scavenged ranging from 12.98 µl·ml-1 to 132.27 µl·ml-1. The strongest antimicrobial activity of samples of wine evaporated to dryness was detected against Bacillus cereus, B. subtilis IP 5832 and Lactobacillus plantarum, minimum inhibitory concentration (MIC) being from < 0.08 mg·ml-1 to 2.50 mg·ml-1. Samples of dealcoholized wine and the original shape wine showed the strongest inhibitory activity against B. cereus (MIC from < 0.39 µl·ml-1 to 0.78 µl·ml-1). Dealcoholized wine samples showed biofilm-inhibitory activity at which 50% of Staphylococcus aureus ATCC 6538 biofilm was reduced, with values ranging from 188 µl·ml-1 to 530 µl·ml-1. The results of the study contribute to the knowledge on the biological activities of Balkan red wines and the potential for developing a nutritive and health-promoting food product. [ABSTRACT FROM AUTHOR]