The Effect of Cold Diluent on the Viable Count of Pseudomonas pyocyanea

The present study was carried out to knowing effect different storage periods of the microbial quality for the Powdered Infant Formula (PIF) after opening the tin, and ensuring from the safety note (after opening, use within 3 weeks). Thirty (30) samples of (PIF) from category (1 – 6 months) in five different types are collected from pharmacies and local markets in Baquba city / Iraq, which are used as substitutes for breast milk during the first day of opening the tin powders such as Total viable count, Total coliform count, Salmonella count and Yeast and Molds count. These experiments repeated at each week of same samples within (5) weeks. Results were obtained at opening the tin, Total viable count (less than 0.05 1.0 x 103 ±1.5x10 CFU/g) were significantly higher than Total Coliform count (less than 0.05 ± 0.3 x 10 CFU/g) and Total Salmonella count (less than 0.05 0 x 10 CFU/g) and Yeasts and Molds (less than 0.05 ± 0.3 x 10 CFU/g). while results obtained at fifth week were (less than 0.05 8.8 x 103 ±5.5x102 CFU/g), (less than 0.05 0.9 x 102 ± 0.4x101 CFU/g), (less than 0.05 0 x 10 CFU/g), (less than 0.05 9.5 x 10 ± 1.2x101 CFU /g) respectively. All samples of (PIF) having non-significant difference. These results compared to Iraqi Quality Standards (IQS), all the results from the opening samples to fifth week were within the range of IQS and USA Environmental Protection Agency (USEPA) and as indicates the hygienic condition of (PIF) without risk level for human health. also observed increase in microbial contamination in each week because increase the moisture content for powdered milk. Can be used more than 3 weeks after opening if stored in good conditions with good hygienic practices during milk preparation.

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Effects of Fermentative Factors on Biochemical, Microbiological and Sensory Characteristics of Probiotic Iranian Fermented Milk (Doogh)

Current Nutrition & Food Science ◽

10.2174/1573401313666170614092802 ◽

2019 ◽

Vol 15 (1) ◽

pp. 40-47

Author(s):

Elaheh Ahmadi ◽

Reza Mohammadi ◽

Sara Hasanvand ◽

Milad Rouhi ◽

Amir Mohammad Mortazavian ◽

...

Keyword(s):

Incubation Temperature ◽

Storage Temperature ◽

Starter Culture ◽

Fermented Milk ◽

Biochemical Properties ◽

Viable Count ◽

Sensory Characteristics ◽

Refrigerated Storage ◽

Increase Rate ◽

Probiotic Strains

Background: Doogh is a traditional Iranian fermented milk drink that is currently a very popular product in Iran. In the present study, the combined effects of incubation temperature, type of starter culture, and final pH of fermentation on the viability of two probiotic strains (Lactobacillus acidophilus La-5 (A) and Bifidobacterium lactis Bb-12 (B)) and biochemical and sensory characteristics of probiotic Doogh were investigated. Method: Different treatments were prepared with yoghurt starter culture containing probiotics, using reconstituted skimmed milk with 6% of solid nonfat. They were incubated at 38°C or 44°C until pH 4.0 or pH 4.5 and were kept for 21 days at 4°C or 8°C storage temperature. The biochemical properties of treatments were evaluated during fermentation and refrigerated storage. The viable count and sensory attributes of treatments were studied at the end of fermentation and at the end of storage. Results: Results showed that the greatest mean pH drop rate, mean acidity increase rate and mean redox potential increase rate and the shortest incubation time were observed in treatments incubated at 44°C with final pH of 4.5. The highest survival of both probiotic strains during storage was related to treatments with fermentation temperature of 38°C and final pH of 4.5. Treatments ABY1-38°C-4.0 had the highest sensorial total acceptance at the end of refrigerated storage. Conclusion: It would be concluded that the best treatment was ABY3-38°C-4 stored at 8°C in regards of probiotics’ viability and sensory characteristics of Doogh. Thus, controlling the temperature of refrigerated storage is the most importance factor during storage and distribution.

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Ventilation-Associated Particulate Matter Is a Potential Reservoir of Multidrug-Resistant Organisms in Health Facilities

Life ◽

10.3390/life11070639 ◽

2021 ◽

Vol 11 (7) ◽

pp. 639

Author(s):

Evgenia Chezganova ◽

Olga Efimova ◽

Vera Sakharova ◽

Anna Efimova ◽

Sergey Sozinov ◽

...

Keyword(s):

Particulate Matter ◽

Prevalence Ratio ◽

Multidrug Resistant ◽

Viable Count ◽

Health Facilities ◽

Hospital Environment ◽

Bacterial Strains ◽

Multidrug Resistant Organisms ◽

Potential Reservoir ◽

Healthcare Associated

Most healthcare-associated infections (HCAIs) develop due to the colonisation of patients and healthcare workers by multidrug-resistant organisms (MDRO). Here, we investigated whether the particulate matter from the ventilation systems (Vent-PM) of health facilities can harbour MDRO and other microbes, thereby acting as a potential reservoir of HCAIs. Dust samples collected in the ventilation grilles and adjacent air ducts underwent a detailed analysis of physicochemical properties and biodiversity. All Vent-PM samples included ultrafine PM capable of reaching the alveoli. Strikingly, >70% of Vent-PM samples were contaminated, mostly by viruses (>15%) or multidrug-resistant and biofilm-producing bacterial strains (60% and 48% of all bacteria-contaminated specimens, respectively). Total viable count at 1 m from the ventilation grilles was significantly increased after opening doors and windows, indicating an association between air flow and bacterial contamination. Both chemical and microbial compositions of Vent-PM considerably differed across surgical vs. non-surgical and intensive vs. elective care units and between health facilities located in coal and chemical districts. Reduced diversity among MDRO and increased prevalence ratio in multidrug-resistant to the total Enterococcus spp. in Vent-PM testified to the evolving antibiotic resistance. In conclusion, we suggest Vent-PM as a previously underestimated reservoir of HCAI-causing pathogens in the hospital environment.

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Detection and Potential Virulence of Viable but Non-Culturable (VBNC) Listeria monocytogenes: A Review

Microorganisms ◽

10.3390/microorganisms9010194 ◽

2021 ◽

Vol 9 (1) ◽

pp. 194

Author(s):

Nathan E. Wideman ◽

James D. Oliver ◽

Philip Glen Crandall ◽

Nathan A. Jarvis

Keyword(s):

Public Health ◽

Listeria Monocytogenes ◽

Viable Count ◽

Vbnc State ◽

Testing Methods ◽

Tetrazolium Chloride ◽

Definitive Evidence ◽

Virulence Potential ◽

Vbnc Bacteria ◽

The Impact

The detection, enumeration, and virulence potential of viable but non-culturable (VBNC) pathogens continues to be a topic of discussion. While there is a lack of definitive evidence that VBNC Listeria monocytogenes (Lm) pose a public health risk, recent studies suggest that Lm in its VBNC state remains virulent. VBNC bacteria cannot be enumerated by traditional plating methods, so the results from routine Lm testing may not demonstrate a sample’s true hazard to public health. We suggest that supplementing routine Lm testing methods with methods designed to enumerate VBNC cells may more accurately represent the true level of risk. This review summarizes five methods for enumerating VNBC Lm: Live/Dead BacLightTM staining, ethidium monoazide and propidium monoazide-stained real-time polymerase chain reaction (EMA- and PMA-PCR), direct viable count (DVC), 5-cyano-2,3-ditolyl tetrazolium chloride-4′,6-diamidino-2-phenylindole (CTC-DAPI) double staining, and carboxy-fluorescein diacetate (CDFA) staining. Of these five supplementary methods, the Live/Dead BacLightTM staining and CFDA-DVC staining currently appear to be the most accurate for VBNC Lm enumeration. In addition, the impact of the VBNC state on the virulence of Lm is reviewed. Widespread use of these supplemental methods would provide supporting data to identify the conditions under which Lm can revert from its VBNC state into an actively multiplying state and help identify the environmental triggers that can cause Lm to become virulent. Highlights: Rationale for testing for all viable Listeria (Lm) is presented. Routine environmental sampling and plating methods may miss viable Lm cells. An overview and comparison of available VBNC testing methods is given. There is a need for resuscitation techniques to recover Lm from VBNC. A review of testing results for post VBNC virulence is compared

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Combination of Direct Viable Count and Fluorescent In Situ Hybridization (DVC-FISH) as a Potential Method for Identifying Viable Vibrio parahaemolyticus in Oysters and Mussels

Foods ◽

10.3390/foods10071502 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1502

Author(s):

Jorge García-Hernández ◽

Manuel Hernández ◽

Yolanda Moreno

Keyword(s):

In Situ Hybridization ◽

Vibrio Parahaemolyticus ◽

Fluorescent In Situ Hybridization ◽

Potential Method ◽

Viable Count ◽

Hybridization Technique ◽

Fish Technique ◽

Viable Cells

Vibrio parahaemolyticus is a human food-borne pathogen with the ability to enter the food chain. It is able to acquire a viable, non-cultivable state (VBNC), which is not detected by traditional methods. The combination of the direct viable count method and a fluorescent in situ hybridization technique (DVC-FISH) makes it possible to detect microorganisms that can present VBNC forms in complex samples The optimization of the in vitro DVC-FISH technique for V. parahaemolyticus was carried out. The selected antibiotic was ciprofloxacin at a concentration of 0.75 μg/mL with an incubation time in DVC broth of 5 h. The DVC-FISH technique and the traditional plate culture were applied to detect and quantify the viable cells of the affected pathogen in artificially contaminated food matrices at different temperatures. The results obtained showed that low temperatures produced an important logarithmic decrease of V. parahaemolyticus, while at 22 °C, it proliferated rapidly. The DVC-FISH technique proved to be a useful tool for the detection and quantification of V. parahaemolyticus in the two seafood matrices of oysters and mussels. This is the first study in which this technique has been developed to detect viable cells for this microorganism.

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Evaluation of non-thermal effect of microwave radiation and its mode of action in bacterial cell inactivation

Scientific Reports ◽

10.1038/s41598-021-93274-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Priyanka Shaw ◽

Naresh Kumar ◽

Sohail Mumtaz ◽

Jun Sup Lim ◽

Jung Hyun Jang ◽

...

Keyword(s):

Thermal Effect ◽

Microwave Radiation ◽

Bacterial Cell ◽

Mode Of Action ◽

Surface Damage ◽

Peak Frequency ◽

Viable Count ◽

Bacterial Inactivation ◽

Bacterial Strains ◽

Log Reduction

AbstractA growing body of literature has recognized the non-thermal effect of pulsed microwave radiation (PMR) on bacterial systems. However, its mode of action in deactivating bacteria has not yet been extensively investigated. Nevertheless, it is highly important to advance the applications of PMR from simple to complex biological systems. In this study, we first optimized the conditions of the PMR device and we assessed the results by simulations, using ANSYS HFSS (High Frequency Structure Simulator) and a 3D particle-in-cell code for the electron behavior, to provide a better overview of the bacterial cell exposure to microwave radiation. To determine the sensitivity of PMR, Escherichia coli and Staphylococcus aureus cultures were exposed to PMR (pulse duration: 60 ns, peak frequency: 3.5 GHz) with power density of 17 kW/cm2 at the free space of sample position, which would induce electric field of 8.0 kV/cm inside the PBS solution of falcon tube in this experiment at 25 °C. At various discharges (D) of microwaves, the colony forming unit curves were analyzed. The highest ratios of viable count reductions were observed when the doses were increased from 20D to 80D, which resulted in an approximate 6 log reduction in E. coli and 4 log reduction in S. aureus. Moreover, scanning electron microscopy also revealed surface damage in both bacterial strains after PMR exposure. The bacterial inactivation was attributed to the deactivation of oxidation-regulating genes and DNA damage.

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COLISTIN IN PSEUDOMONAS PYOCYANEA INFECTIONS AND ITS EFFECT ON RENAL FUNCTION

British Journal of Urology ◽

10.1111/j.1464-410x.1966.tb09743.x ◽

1966 ◽

Vol 38 (5) ◽

pp. 495-500 ◽

Cited By ~ 4

Author(s):

W. BRUMFITT ◽

M. BLACK ◽

J. D. WILLIAMS

Keyword(s):

Renal Function ◽

Pseudomonas Pyocyanea

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Morphological and Physiological Responses of Campylobacter jejuni to Stress

Journal of Food Protection ◽

10.4315/0362-028x-69.11.2747 ◽

2006 ◽

Vol 69 (11) ◽

pp. 2747-2753 ◽

Cited By ~ 19

Author(s):

PUSSADEE TANGWATCHARIN ◽

SUGANYA CHANTHACHUM ◽

PRAPAPORN KHOPAIBOOL ◽

MANSEL W. GRIFFITHS

Keyword(s):

Campylobacter Jejuni ◽

Viable Count ◽

Cell Suspensions ◽

Evolutionary Strategy ◽

Transmission Electron ◽

Proteomic Study ◽

Nonculturable Cells ◽

Plate Counts ◽

Stressed Cell ◽

Aging Cell

Under conditions of stress, cells of Campylobacter assume a coccoid shape that may be an evolutionary strategy evolved by the organism to enable survival between hosts. However, the physiology of Campylobacter as it devolves from spiral to coccoid-shaped morphology is poorly understood. In this study, conditions influencing the survival of Campylobacter jejuni ATCC 35921 in broth were determined. Cells in late log phase were resuspended in broth at 4 or 60°C. The culturability of these cold- or heat-stressed cell suspensions was determined by spread plate counts and the activity of cells by the direct viable count technique and 5-cyano-2,3-ditolyltetrazolium chloride staining. C. jejuni changed form completely from culturable to viable but nonculturable cells (VBNC) within 25 days at 4°C, and 15 min at 60°C. Light microscopy of C. jejuni VBNC cells showed that the spiral-shaped cells became coccoid, and transmission electron microscopy of C. jejuni VBNC cells showed that the outer membrane was lost in aging cell suspensions. Furthermore, a limited proteomic study was carried out to compare C. jejuni proteins that exhibited increased or decreased synthesis on exposure to 60°C.

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Isolation and Characterization of Two Lytic Bacteriophages Infecting a Multi-Drug Resistant Salmonella Typhimurium and Their Efficacy to Combat Salmonellosis in Ready-to-Use Foods

Microorganisms ◽

10.3390/microorganisms9020423 ◽

2021 ◽

Vol 9 (2) ◽

pp. 423

Author(s):

Ahmed Esmael ◽

Ehab Azab ◽

Adil A. Gobouri ◽

Mohamed A. Nasr-Eldin ◽

Mahmoud M. A. Moustafa ◽

...

Keyword(s):

Salmonella Typhimurium ◽

Multidrug Resistant ◽

Viable Count ◽

Food Storage ◽

Chicken Breast ◽

Whole Genome Analysis ◽

Isolation And Characterization ◽

Phage Cocktail ◽

Global Threat

Foodborne salmonellosis is a global threat to public health. In the current study, we describe the isolation and characterization of two broad-spectrum, lytic Salmonella phages: SPHG1 and SPHG3 infecting a multidrug-resistant Salmonella Typhimurium EG.SmT3. Electron microscopy and whole genome analysis identified SPHG1 as a Myovirus, while SPHG3 as a new member of the genus “Kuttervirus” within the family Ackermannviridae. SPHG1 and SPHG3 had a lysis time of 60 min. with burst sizes of 104 and 138 PFU/cell, respectively. The two phages were robust at variable temperatures and pH ranges that match the corresponding values of most of the food storage and processing conditions. A phage cocktail containing the two phages was stable in the tested food articles for up to 48 h. The application of the phage cocktail at MOIs of 1000 or 100 resulted in a significant reduction in the viable count of S. Typhimurium by 4.2 log10/sample in milk, water, and on chicken breast. Additionally, the phage cocktail showed a prospective ability to eradicate and reduce the biofilm that formed by S. Typhimurium EG.SmT3. A phage cocktail of SPHG1 and SPHG3 is considered as a promising candidate as a biocontrol agent against foodborne salmonellosis due to its broad host ranges, highly lytic activities, and the absence of any virulence or lysogeny-related genes in their genomes.

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PSEUDOMONAS PYOCYANEA WOUND INFECTION AN OUTBREAK IN AN ORTHOPÆDIC UNIT

The Lancet ◽

10.1016/s0140-6736(60)91795-5 ◽

1960 ◽

Vol 276 (7153) ◽

pp. 734-736 ◽

Cited By ~ 5

Author(s):

M. Sussman ◽

J. Stevens

Keyword(s):

Wound Infection ◽

Pseudomonas Pyocyanea

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