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The pathogenic and spoilage microorganisms affect human health directly or indirectly and become increasingly important in most countries. Novel antimicrobial agents and disinfectants have become necessary due to the rise of antibiotic resistance phenomena. The current study investigate the inhibitory infect of ANOSAN on pathogenic bacteria and toxigenic fungi. Chemical analysis was performed for ANOSAN. The antimicrobial activity of ANOSAN was carried out using agar well diffusion assay and mean growth inhibition percentage and Minimum Inhibitory Concentration (MIC). The antibiofilm activity was conducted using Biofilm formation assay and the impact of the disinfectant on the preformed biofilm was visualized by Scanning Electron Microscope (SEM). The chemical composition of ANOSAN comprised very low amount of Sodium (0.034%), Chloride (0.01%), Hypochlorite (0.014%) and Organic matter (0.0062%). ANOSAN low concentration showed a broad spectrum of antibacterial activities against Gram positive, Gram negative bacteria and fungi. The MIC (0.781 mg/ml) was observed for Vibrio cholerae, Pseudomonas aeruginosa and Staphylococcus aureus. Sub-inhibitory concentrations of ANOSAN have successfully inhibited biofilm formation of the above mentioned bacterial pathogens. The ANOSAN appeared to be effective as bactericidal against Ps. aeruginosa and Staph. aureus. The time kill assay was observed between (0-6h) and between (0-3h) of exposure for both pathogens, respectively, and the viable bacterial counts remained undetectable after the previous time in a confirmatory experiment. Scanning Electron Microscopy (SEM) was conducted to confirm the antimicrobial activity of ANOSAN against Staph. aureus and Ps. aeruginosa. These data directly illustrate the destructive effects of the ANOSAN on the pathogenic bacteria. This work clarified that ANOSAN water had bactericidal and fungicidal activity along with inhibiting the ability of pathogenic bacteria to form biofilms, thus providing a good alternative to the use of traditional antimicrobials in food industry, pharmaceutical and medical applications. [ABSTRACT FROM AUTHOR]

Abstract Bacteriophages have been envisioned as tools to control a variety of foodborne pathogenic bacteria. Salmonella is a foodborne pathogen that is a threat to public health around the world. Contaminated tomatoes have been associated with several Salmonella outbreaks. Hence, the objective of this work was to identify and characterize different lytic bacteriophages against Salmonella Newport, as one of top ten Salmonella serovars associated with human salmonellosis in North America, and then apply these phages to enhance the safety of cherry tomatoes. Four lytic phages against Salmonella Newport were selected based on their ability to lyse a majority of the 26 screened Salmonella serovars. The selected phages belong to Myoviridae (vB_SnwM_CGG4-1, vB_SnwM_CGG4-2) and Siphoviridae (vB_SnwM_CGG3-1, vB_SnwM_CGG3-2) families. They were found to be stable at different temperatures and pH, have latent periods ranging from 53 to 65 min and burst sizes from 92 to 177. In addition, the two Myoviridae phages have a lower frequency of developing bacteriophage insensitive mutants when compared with the Siphoviridae phages. No significant change in virulence gene expression was observed in the developed bacteriophage insensitive mutants when compared to the parental phage sensitive strain. Furthermore, the vB_SnwM_CGG4-1 genome revealed no homology to virulence or lysogenic genes. A phage cocktail was used to control the growth of S. Newport in broth medium and on contaminated cherry tomato. Complete inhibition of bacterial growth in broth medium was observed at 25 °C for 24 h. In addition, a 4.5 log 10 unit reduction in the bacterial count was observed when applying the phage cocktail onto contaminated tomatoes stored at 22 °C for 3 days. These findings suggest that the isolated phages can be used for biocontrol of S. Newport to improve the safety of ready-to-eat (RTE) produce. Highlights • Four lytic and broad host range Salmonella phages were isolated and characterized. • No homology to virulence or lysogenic genes was observed in the sequenced phage. • Phage cocktail completely inhibited S. Newport growth in broth medium. • Phage cocktail caused 4.5 log 10 unit reduction in S. Newport count onto tomatoes. • The isolated phages can be used to improve the safety of ready-to-eat produce. [ABSTRACT FROM AUTHOR]

This paper presents a review of the design parameters, mathematical techniques and simulations used in the design of parabolic trough solar systems, along with a review on their applications. Recent studies that analyze the deployment of solar parabolic trough collectors (SPTC) in different countries and the operational SPTC plants are also presented and discussed. The paper also discusses the different kinds of software and test methods of solar collectors developed since 1981 which can be distinguished by their particular mathematical models or tracking techniques. In particular, since the mathematical models are especially required for the design, analysis, testing and validation of the systems results as they provide an approximation of the dynamic behavior of the physical properties of the system, they are discussed in depth. The mathematical models allow the calculation of different parameters of the solar parabolic trough system, the angle of inclination of the collecting surface and the forces acting on the system. The validity and experimental validation of the major mathematical models on practical solar parabolic trough concentrators, receivers and other components of different dimension are also reviewed. The paper showed the optical efficiency values are close to 63% and the theoretical peak optical efficiency reached 75%. [ABSTRACT FROM AUTHOR]