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In this study, molecular identification of Lactiplantibacillus pentosus v390 was performed using 16S rRNA gene analysis with FYM27 and R1492 primers. The viability of the strain was assessed under acidic conditions at pH 2.5, 3.5 and 4.5, and resistance to bile at concentrations of 0%, 0.3%, 0.5%, and 0.7% was investigated. Antioxidant activity, cholesterol absorption, hydrophobicity, potential for DNase enzyme production, biogenic amines, hemolytic activity, and resistance to common therapeutic antibiotics were evaluated. The antimicrobial effect of the strain against pathogenic bacteria (Shigella dysenteriae, Salmonella enterica serovar Typhimurium, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Bacillus subtilis) was examined using the well and disk diffusion method. The results showed that the L. pentosus v390 strain had the ability to survive at different pH levels, but after three hours of storage at pH 2.5, the bacterial count decreased. The strain demonstrated growth capability at various bile salt concentrations. L. pentosus v390 was intermediate to the antibiotic Nitrofurazone, resistant to Nalidixic and Imipenem antibiotics, and sensitive to Vancocin, Gentamicin, Chloramphenicol, Penicillin, and Ciprofloxacin antibiotics. The hydrophobicity, antioxidant activity (DPPH and ABTS), and cholesterol absorption of the strain were 46.50 ± 0.38%, 37.20 ± 0.40%, 39.90 ± 0.45%, and 36.50 ± 0.47%, respectively. No DNase enzyme production, biogenic amines, or hemolytic activity were observed from the strain. L. pentosus v390 exhibited stronger antimicrobial effects against Gram -positive bacteria. The results indicated that L. pentosus v390 has desirable probiotic properties that require further research to confirm its application potential in food product development. [ABSTRACT FROM AUTHOR]

Nowadays, Functional food products as healthy diets have been considered extensively among consumers. Moreover, the use of particular microorganisms, for instance probiotic bacteria, offers probabilities to progress novel foods with appropriate shelf life. In the current research, in order to produce a functional ultrafiltrated (UF)-cheese, demineralized UF-whey powder (DUWP) at the levels of 0, 1 and 2%, and lactulose powder at the levels of 0 and 1% were used. Furthermore, bifidobacterium bifidum was used as probiotic bacteria. The textural characteristics in terms of hardness, cohesiveness, adhesiveness, springiness, gumminess and chewiness and sensorial propertis of the symbiotic cheese samples including odor, color, texture and taste were evaluated during 60 days of storage period at 4 ◦C. Results showed that addition of DUWP and lactulose powders except for adhesiveness and springiness caused significant decrease in all textural parameters (P<0.001). Besides, except for adhesiveness and cohesiveness, the mean values of textural parameters usually enhanced up to middle of the storage time and thereafter decreased up to end of storage period (p<0.05). Sensory results revealed that although addition of both DUWP and lactulose powders resulted in lower sensory scores, no significant differences were found between control (without DUWP and lactulose) and sample containing 1% of each both mentioned powders (P>0.05). Therefore, based on the obtained results, sample having 1% of DUWP and 1% of lactulose determined as the best symbiotic UF-cheese sample. Since the potential contribution of this product in community health promotion and reduction of diseases risk, the production and consumption of this functional cheese is proposed. [ABSTRACT FROM AUTHOR]

Background and Objectives: The aim of this study was to assess protection mechanisms against Escherichia coli by analyzing aggregation, adherence, antagonistic activity and safety characteristics of potentially probiotic Lactobacillus acidophilus B103. Materials and Methods: Potentially probiotic L. acidophilus B103 has been investigated in various aspects. Studied key characteristics included its pH and bile resistance, cell surface hydrophobicity and aggregation, cholesterol removal ability, hydroxyl radical scavenging activity and adhesion ability to Caco-2 cell monolayers. Antagonistic activity of the strain was assessed by adhesion competition on E. coli via competition, inhibition and replacement assays. Moreover, safety characteristics were investigated through DNase, hemolytic activity, biogenic amine production and antibiotic susceptibility assays. Results: L. acidophilus B103 included high stability to acidic pH (2.5 and 4.5), simulated gastric and intestinal juices and bile salt concentrations (up to 5% w/v). Moreover, L. acidophilus B103 showed relatively high hydrophobicity (51.79%), auto-aggregation (42.38%), co-aggregation (34.48%), cholesterol removal (46.27%) and hydroxyl radical scavenging activities (51.36%). Competition, replacement and inhibition anti-adhesion assays of the strain against E. coli were 52.13, 25.20 and 46.40%, respectively. Furthermore, L. acidophilus B103 adhered to simulated epithelial cells with a capacity of 11.85%. Neither DNase nor hemolytic activity was observed in the bacterial strain and the strain was highly sensitive to ciprofloxacin. Conclusions: Based on the results, safety assessments and its food origin, L. acidophilus B103 demonstrates potential for use in the food industry. It can serve as starter culture, co-culture and bio-protective agent, effectively enhancing safety and quality of the food products. [ABSTRACT FROM AUTHOR]

Nowadays, polymers obtained from edible resources such as polysaccharides and proteins have attained growing consideration to substitute petroleum-derived polymers. Edible films are a good alternative for the plastic packaging since these films are biodegradable, environmental-friendly and non-toxic. However, protein based edible films have poor water permeability and lower mechanical strength. In this study, edible films based on whey protein isolate (WPI) were produced with different microbial transglutaminase (MTG) concentrations (0, 5, 10 and 15 Unit/g of protein) and the effect of enzymatic treatment on the film properties was investigated. Results showed that as compared to control, the treatment with the lower concentration of MTG (5-10 U/g) significantly increased the tensile strength (TS) and decreased elongation at rapture (ER) values of WPI-films, while at the higher concentration of MTG (15 U/g), TS value slightly decreased and ER values significantly increased. By increasing the enzyme concentration from 5 to 10 U/g, water vapor transferability (WVT) and water soluble fractions (WSF) decreased significantly (P=0.05). The MTG-treated films except the film treated with 15 U/g TG, had homogeneous and even surface without any crack or fracture. Based on results, treatment with MTG enzyme may be applied as an appropriate technique to modify the structural and barrier properties of WPI-based films. [ABSTRACT FROM AUTHOR]

Abstract: Whey protein films containing antimicrobial compounds provide another layer of protection and thereby may extend the shelf life of food products. In this research, the effect of Satureja khuzistanica Jamzad essential oil (SKJEO) at the concentrations of 0 (as control), 0.5, 1, and 2% (wt/wt, in the film forming solution) on the characteristics of cross‐linked whey protein isolate‐based films was studied. The films incorporated with SKJEO had significantly (p < .05) lower moisture content (MC), total soluble maters (TSM), and tensile strength (TS) but the higher water vapor permeability (WVP) and elongation at break (EB) compared to the control. Control had uniform microstructure, while the films incorporated with SKJEO showed lumpy surface. The films incorporated with the SKJEO had good antimicrobial properties, the higher SKJEO concentration, and the stronger antimicrobial activity. Pseudomonas aeruginosa was the most resistant bacteria, and Staphylococcus aureus was the most sensitive bacteria against SKJEO. Based on our results, it is suggested to use of the SKJEO as a natural antibacterial agent in food packaging particularly those that are highly sensitive to microbial deterioration. Practical applications: Edible films and coatings have been developed in food conservation for many years. Antimicrobial packaging is a form of active packaging that could extend the shelf life of product and provides microbial safety for consumers. Whey proteins films have good barrier properties against organic vapor, gas, and oil as related to artificial films. Our study showed that the SKJEO has remarkable antibacterial activity, which can be applicable to prevent of various food‐related diseases caused by bacteria. Nevertheless, further studies are required to understand the mechanisms of antimicrobial action of SKJEO against microorganisms and more information is mandatory on safety, efficacy, and toxicity for its usage as a natural preservative in different food products. The cross‐linked WPI‐based film containing SKJEO is a favorable resource for the packaging industry since it offers a maintainable and biodegradable packaging material that provides all the packaging materials requirements. [ABSTRACT FROM AUTHOR]

The effect of Persian and almond gums (0, 0.1 and 0.2% (w/w)) as fat replacers and milk fat (0.4, 0.9, and 1.4% (w/w)) on physicochemical and rheological characteristics and microstructure of low-fat Iranian White cheese was studied. Persian and almond gums both effectively increased moisture-to-protein (M:P) ratio of low-fat cheese samples which in turn led to a significant reduction in the hardness parameters fracture stress and Young's and storage (G') moduli ( p < .05); however, the effect of Persian gum was more pronounced ( p < .01). Gum addition promoted cheese yield and proteolysis rate ( p < .05). Response surface optimization described that supplementation of cheese milk containing 0.9% fat with 0.2% Persian gum and 0.12% almond gum would result in a low-fat cheese with textural properties similar to its full-fat counterpart. Scanning electron microscopy revealed that the fat replacers produced full-fat-like structure in the low-fat Iranian White cheese, when incorporated at the optimum levels. [ABSTRACT FROM AUTHOR]