Presence Of Pathogenic Bacteria Research Articles

Antimicrobial peptides secreted by equine mesenchymal stromal cells inhibit the growth of bacteria commonly found in skin wounds

BackgroundThe prevalence of chronic skin wounds in humans is high, and treatment is often complicated by the presence of pathogenic bacteria. Therefore, safe and innovative treatments to reduce the bacterial load in cutaneous wounds are needed. Mesenchymal stromal cells (MSC) are known to provide paracrine signals that act on resident skin cells to promote wound healing, but their potential antibacterial activities are not well described. The present study was designed to examine the antibacterial properties of MSC from horses, as this animal model offers a readily translatable model for MSC therapies in humans. Specifically, we aimed to (i) evaluate the in vitro effects of equine MSC on the growth of representative gram-negative and gram-positive bacterial species commonly found in skin wounds and (ii) define the mechanisms by which MSC inhibit bacterial growth.MethodsMSC were isolated from the peripheral blood of healthy horses. Gram-negative E. coli and gram-positive S. aureus were cultured in the presence of MSC and MSC conditioned medium (CM), containing all factors secreted by MSC. Bacterial growth was measured by plating bacteria and counting viable colonies or by reading the absorbance of bacterial cultures. Bacterial membrane damage was detected by incorporation of N-phenyl-1-naphthylamine (NPN). Antimicrobial peptide (AMP) gene and protein expression by equine MSC were determined by RT-PCR and Western blot analysis, respectively. Blocking of AMP activity of MSC CM was achieved using AMP-specific antibodies.ResultsWe found that equine MSC and MSC CM inhibit the growth of E. coli and S. aureus, and that MSC CM depolarizes the cell membranes of these bacteria. In addition, we found that equine MSC CM contains AMPs, and blocking these AMPs with antibodies reduces the effects of MSC CM on bacteria.ConclusionsOur results demonstrate that equine MSC inhibit bacterial growth and secrete factors that compromise the membrane integrity of bacteria commonly found in skin wounds. We also identified four specific AMPs produced by equine MSC. The secretion of AMPs may contribute to the value of MSC as a therapy for cutaneous wounds in both horses and humans.

Critical points and the presence of pathogenic bacteria in iced beverage processing lines

Ice can be contaminated by pathogenic bacteria. This study aimed to identify critical points in iced beverage production and distribution lines to examine the presence of pathogenic bacteria in a beverage and its processing environment, as well as when water and ice used as main ingredients. The critical points were determined using the principles of Hazard Analytical Critical Control Point (HACCP) to analyze each processing and distribution step from the survey. Samples collected from the points of concern based on the critical points that were found were tested for pathogens by conventional method and molecular method using primers and polymerase chain reaction (PCR). Escherichia coli was found in 6.34% of samples, and 0.7% of them were confirmed as enterotoxigenic Escherichia coli (ETEC) by PCR. Vibrio cholerae was found in in 0.7% of water samples used to make iced beverages and in ice production, as well as in 2.12% of distribution and production tools. Salmonella Typhimurium was found in 1.4% of water samples used to make ice and ice products. Staphylococcus aureus was found in 2.02% of the surfaces of ice distribution and production tools and in 5.05% of production and distribution workers' hands. S. aureus counts ranged from 2.4×102 - 3.5×102 colonies/100 cm² surface area and 1.9×10¹ - 3.7×102 colonies/workers' hands. Control on many critical points in iced beverage processing and distribution is required so that the beverages are safe for consumption.

Importance of feed structure (particle size) and feed form (mash vs. pellets) in pig nutrition – A review

Pigs are monogastric animals with simple, single-chambered stomach and require easily digestible, high quality feed. One of the most important factors that determine feed utilization by pigs is the particle size distribution. The reduction of particle size of feed improves pigs’ performance due to increased specific surface of feed particles allowing better contact with digestive enzymes. In this respect, fine grinding could be recommended in production of pig feed. Additionally, in modern pig production dry feed is predominantly used in pelleted form, which is mainly due to improved (i.e. decreased) feed conversion ratio (FCR) of pigs fed pelleted feed, but also due to other advantages of pelleted over mash feed.Size of feed particles is strongly reduced during pelleting process. Consequently, digestibility of nutrients in pig feed could be improved. On the other hand, presence of high quantities of fine particles in pig feed (both mash and pelleted) negatively affects the health of gastro-intestinal tract (GIT) leading to higher incidence of stomach ulceration and other negative alterations of gastric mucosa (keratization, erosions). Gastric ulcers are one of the most important causes of sudden death on farm that can result in large economic losses in pig production. Concerning that the animal therapy is expensive, labor-intensive, and mostly non-effective due to late recognition of ulceration, prophylactic recommendations are required. Thus, according to literature data, decreasing the quantity of fine particles in pig feed is strongly recommended.Particle size distribution of the pigs’ feed has a strong influence on presence of pathogen bacteria in GIT of pigs. Feeding pigs with coarse mash feed decreases pH value of stomach content compared to pigs fed finely ground mash feed and compared to pigs fed pelleted feed. This can be explained by slower passage rate, increased dry matter, and more dense consistency of stomach content in pigs fed coarse mash diets. Consequently, feed acidification in stomach is better, number of lactic acid bacteria and concentration of organic acids is higher, and pH of stomach content is lower. These conditions create additional “barrier” against pathogen bacteria.According to available data, optimal particle size of diets for pigs is in the range between 500 and 1600μm, while particles smaller than 400μm are considered as undesirable with high ulcerogenic capacity. Optimal particle size could be designed in the grinding process, and it was shown that the most convenient grinding method is to combine roller mill and hammer mill. Concerning that nowadays pigs are mainly fed pelleted feed, and that pelleting causes strong additional grinding of feed particles, particle size distribution (PSD) obtained within the grinding process would be dramatically changed during pelleting. The possibilities to decrease the intensity of grinding of particles during pelleting, by variation of parameters of pelleting process, are very limited. Modified extrusion process (i.e. processing using expander) followed by shaping element, is suggested in the literature as an alternative for pelleting in order to obtain agglomerated pig feed with preserved PSD, but this process is not extensively studied so far.

Evidence for altered levels of IgD in the nasal airway mucosa of patients with chronic rhinosinusitis

IgD is an enigmatic antibody isotype best known when coexpressed with IgM on naive B cells. However, increased soluble IgD (sIgD) levels and increased IgD+IgM- B-cell populations have been described in the human upper respiratory mucosa. We assessed whether levels of sIgD and IgD+ B cell counts are altered in nasal tissue from patients with chronic rhinosinusitis (CRS). We further characterized IgD+ B-cell populations and explored clinical and local inflammatory factors associated with tissue sIgD levels. sIgD levels were measured by means of ELISA in nasal tissues, nasal lavage fluid, sera, and supernatants of dissociated nasal tissues. IgD+ cells were identified by using immunofluorescence and flow cytometry. Inflammatory mediator levels in tissues were assessed by using real-time PCR and multiplex immunoassays. Bacterial cultures from the middle meatus were performed. Underlying medical history and medicine use were obtained from medical records. sIgD levels and numbers of IgD+ cells were significantly increased in uncinate tissue (UT) of patients with chronic rhinosinusitis without nasal polyps (CRSsNP) compared with that of control subjects (4-fold, P<.05). IgD+ cells were densely scattered in the periglandular regions of UT from patients with CRSsNP. We also found that IgD+CD19+CD38bright plasmablast numbers were significantly increased in tissues from patients with CRSsNP compared with control tissues (P<.05). Among numerous factors tested, IL-2 levels were increased in UT from patients with CRSsNP and were positively correlated with tissue IgD levels. Additionally, supernatants of IL-2-stimulated dissociated tissue from patients with CRSsNP had significantly increased sIgD levels compared with those in IL-2-stimulated dissociated control tissue exvivo (P<.05). Tissue from patients with CRS with preoperative antibiotic use or those with pathogenic bacteria showed higher IgD levels compared with tissue from patients without these variables (P<.05). sIgD levels and IgD+CD19+CD38bright plasmablast counts were increased in nasal tissue of patients with CRSsNP. IgD levels were associated with increased IL-2 levels and the presence of pathogenic bacteria. These findings suggest that IgD might contribute to enhancement mucosal immunity or inflammation or respond to bacterial infections in patients with CRS, especially CRSsNP.

Perlakuan Celup Puting setelah Pemerahan terhadap Keberadaan Bakteri Patogen, Staphylococcus aureus, Streptococcus agalactiae, dan E. coli pada Sapi Perah Penderita Mastitis Subklinis di Peternakan KUNAK Bogor

Mastitis is udder inflammation that can be caused by the entry of pathogenic bacteria through the teat. One of the treatments that can prevent bacteria infection is teat dipping. This research was aimed to identify the effectof teat dipping after milking to the presence of pathogenic bacteria that cause subclinical mastitis (Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli) and the presence of pathogenic bacteria that cause subclinicalmastitis by quarter of udder. Milk samples were taken from normal lactation period of dairy cows, clinically healthy, and positive subclinical mastitis status when the intervention was applied. Sixty seven samples of quarters from 18dairy cows were identified to the presence of pathogenic bacteria that cause subclinical mastitis before teat dipping and at 1st, 2nd, and 3rd months after teat dipping. Identification of the presence of pathogenic bacteria was done byculturing samples on selective agar media. The presence of common pathogenic bacteria, Staphylococcus aureus, and Escherichia coli decreased significantly after teat dipping, while Streptococcus agalactiae and other pathogenicbacteria did not decrease significantly. The presence of pathogenic bacteria based on the quarter of udder did not show the significance difference. Application of teat dipping after milking was able to decrease the presence ofpathogenic bacteria that cause subclinical mastitis.

Microbiologic and histopathological findings of osteomyelitis in diabetic patients

Osteomyelitis can present as a severe complication in diabetic patients. The present study was structured to evaluate the histopathological characteristics of bone infection in the feet of diabetic patients and to associate any clinical variables seen with each type of bone infection. Eighty-four cases of osteomyelitis were evaluated microbiologically and histopathologically after samples were collected under sterile conditions in an operating room. The data generated were analysed using SPSS software. Polymorphonuclear neutrophil (PMN) infiltrates were associated with acute osteomyelitis (AO) (22 cases (26.2%)) and chronic acute osteomyelitis (CAO) (10 cases (11.9%)), whereas a strong association was observed between mononuclear infiltrates and chronic osteomyelitis (CO) (33 cases (39.3%)) and fibrosis (19 cases (22.6%)). Ulcer longevity on hospital admission varied for each condition: AO (10.9 + 22 weeks), CO (29.1 + 20.6 weeks), CAO (31.5 + 22.2 weeks) and fibrosis (30.5 + 23 weeks) (P < 0.05) (values expressed as mean + SD). The same was true for the presence of pathogenic bacteria: AO (16/22, 72.7%), CO (27/33, 81.8%), CAO (7/10, 70%) and fibrosis (16/19, 84.2%). There was significant correlation between histopathological features and presence of bacteria and longevity of the ulcer on presentation (P < 0.05). Osteomyelitis in the feet of diabetic patients should be classified as four specific but interlinked groups: acute, chronic, acute on chronic and fibrosis.

Evaluating the biosafety of conventional and O3-BAC process and its relationship with NOM characteristics

ABSTRACTIt is the priority to guarantee biosafety for drinking water treatment. The objective of this study was to evaluate the impact of widely applied conventional and ozone-biological activated carbon (O3-BAC) advanced treatment technology on biosafety of drinking water. The items, including assimilable organic carbon (AOC), biodegradable dissolved organic carbon (BDOC), heterotrophic plate counts (HPCs) and the microorganism community structures, were used to evaluate the biosafety. Moreover, their relationships with molecular weights (MWs) and fluorescence intensity of dissolved organic matter were investigated. The results indicated that the technology provided a considerable gain in potable water quality by decreasing dissolved organic carbon (DOC, from 5.05 to 1.71 mg/L), AOC (from 298 to 131 μg/L), BDOC (from 1.39 to 0.24 mg/L) and HPCs (from 275 to 10 CFU/mL). Ozone brought an increase in DOC with low MW <1 kDa, which accompanies with an increase in AOC/BDOC concentration, which could be reduced effectively by subsequent BAC process. The formation of AOC/BDOC was closely related to DOC with low MWs and aromatic protein. Bacteria could be released from BAC filter, resulting in an increase in HPC and the presence of pathogenic bacteria in effluent, while the post sand filter could further guarantee the biosafety of finished water.

Microorganisms and heavy metals associated with atmospheric deposition in a congested urban environment of a developing country: Sri Lanka.

The presence of bacteria and heavy metals in atmospheric deposition were investigated in Kandy, Sri Lanka, which is a typical city in the developing world with significant traffic congestion. Atmospheric deposition samples were analyzed for Al, Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb which are heavy metals common to urban environments. Al and Fe were found in high concentrations due to the presence of natural sources, but may also be re-suspended by vehicular traffic. Relatively high concentrations of toxic metals such as Cr and Pb in dissolved form were also found. High Zn loads can be attributed to vehicular emissions and the wide use of Zn coated roofing materials. The metal loads in wet deposition showed higher concentrations compared to dry deposition. The metal concentrations among the different sampling sites significantly differ from each other depending on the traffic conditions. Industrial activities are not significant in Kandy City. Consequently, the traffic exerts high influence on heavy metal loadings. As part of the bacterial investigations, nine species of culturable bacteria, namely; Sphingomonas sp., Pseudomonas aeruginosa, Pseudomonas monteilii, Klebsiella pneumonia, Ochrobactrum intermedium, Leclercia adecarboxylata, Exiguobacterium sp., Bacillus pumilus and Kocuria kristinae, which are opportunistic pathogens, were identified. This is the first time Pseudomonas monteilii and Ochrobactrum intermedium has been reported from a country in Asia. The culturable fraction constituted ~0.01 to 10%. Pigmented bacteria and endospore forming bacteria were copious in the atmospheric depositions due to their capability to withstand harsh environmental conditions. The presence of pathogenic bacteria and heavy metals creates potential human and ecosystem health risk.

Microbial Interactions in the Phyllosphere Increase Plant Performance under Herbivore Biotic Stress.

The phyllosphere supports a tremendous diversity of microbes and other organisms. However, little is known about the colonization and survival of pathogenic and beneficial bacteria alone or together in the phyllosphere across the whole plant life-cycle under herbivory, which hinders our ability to understand the role of phyllosphere bacteria on plant performance. We addressed these questions in experiments using four genetically and biogeographically diverse accessions of Arabidopsis thaliana, three ecologically important bacterial strains (Pseudomonas syringae DC3000, Xanthomonas campestris, both pathogens, and Bacillus cereus, plant beneficial) under common garden conditions that included fungus gnats (Bradysia spp.). Plants supported greater abundance of B. cereus over either pathogenic strain in the phyllosphere under such greenhouse conditions. However, the Arabidopsis accessions performed much better (i.e., early flowering, biomass, siliques, and seeds per plant) in the presence of pathogenic bacteria rather than in the presence of the plant beneficial B. cereus. As a group, the plants inoculated with any of the three bacteria (Pst DC3000, Xanthomonas, or Bacillus) all had a higher fitness than uninoculated controls under these conditions. These results suggest that the plants grown under the pressure of different natural enemies, such as pathogens and an herbivore together perform relatively better, probably because natural enemies induce host defense against each other. However, in general, a positive impact of Bacillus on plant performance under herbivory may be due to its plant-beneficial properties. In contrast, bacterial species in the mixture (all three together) performed poorer than as monocultures in their total abundance and host plant growth promotion, possibly due to negative interspecific interactions among the bacteria. However, bacterial species richness linearly promoted seed production in the host plants under these conditions, suggesting that natural enemies diversity may be beneficial from the host perspective. Collectively, these results highlight the importance of bacterial community composition on plant performance and bacterial abundance in the phyllosphere.

Pathogenic Bacteria in Oreochromis Niloticus Var. Stirling Tilapia Culture

Tilapia Oreochromis niloticus is an aquaculture resource that represents one of the most popular crops in the world. However, species cultivation presents health problems, which are associated with the presence of pathogenic bacteria and causes high economic losses. The aim of this study was to determine the diversity of these bacteria at the genus level in the species O. niloticus var. Styrling during growing stage in the fattening and pre-fattening phases. Tilapia samples were collected and analyzed; each sample was subjected to a macroscopic external and internal observation of organs and tissues. Subsequently, samples were evaluated by microbiological tests using Trypticase Soy Agar (TSA), Thiosulfate Citrate Bile Salts Sucrose Agar (TCBS) and selective media (Pseudomonas sp. Group), and conventional biochemical tests aimed at the production of glucose, sucrose, lactose, oxidase, catalase, indole, ornithine and Gram staining. External analysis revealed clinical signs of disease such as skin bleeding, body ulceration, corneal opacity, and intestine and vesicle inflammation. Microbiological and biochemical analysis showed the presence of eleven bacterial genera known as Arthrobacter sp., Enterococcus sp., Staphylococcus sp., Micrococcus sp., Streptococcus sp., Aeromonas sp., Pseudomonas sp., Edwardsiella sp., Flexibacter sp. and Flavobacterium sp., with a predominance of 55% Gram-negative bacilli in tilapia crops. According to the results, it is necessary to take preventive and corrective measures in order to avoid possible risks during production cycles, mainly when handling organisms. It is also important to promote good crop management practices and quality systems in production units to benefit the aquaculture sector.

Occurrence of Clostridium perfringens in sausages sold in Meknes city, Morocco.

In Morocco, the consumption of meat products has experienced a sharp increase in recent years despite the presence of pathogenic bacteria due to hygiene failure. The present study was designed to determine the prevalence of Clostridium perfringens in sausages sold in Meknes city (Morocco) and to study the different factors affecting it contamination with this bacterium. To this end, 156 samples of sausages were taken in various shopping sites during one year from March 2014 to February 2015. The microbiological analysis was carried out using the specific medium for isolation and identification of C. perfringens. ANOVA test was used for Statistical analysis (p< 0.05). The results of this study showed the presence of C. perfringens in 77.56% (121 of 156) samples, with 88.88% (32 of 36) in street vendors, 79.16% (19 of 24) in a weekly market, 70.83% (51 of 72) in butchery and 62.5% (15 of 24) in a supermarket. The average rate was 2.42 Log CFU/g, with a minimum value of 0 CFU/g recorded in several outlets and a maximum value of 6.05 Log CFU/g recorded in butchery. This study reveals that the contamination rate of sausages with C. perfringens is related to the sausages origin, retail sites and seasonal variations related to temperature increase.

Detection of Extended Spectrum B-Lactamases Among Bacteria Isolated from Snacks Sold Within Kaduna State Metropolis Northwest Nigeria

Extended spectrumβ-lactamses (ESBL) are a group of plasmid mediated, diverse, complex, and rapidly evolving enzymes that are posing a major therapeutic challenge today in the treatment of hospitalized and community patients. Due to non-regulation of snacks, people are exposed to pathogenic bacteria. The aim of this study is to detect extended spectrum β-lactamases among bacteria isolates from snack foods sold in Kaduna metropolis Nigeria. A total of 144 samples comprising of meat-pie, doughnut, egg-roll, buns, samosa, burger and pizza were cultured on blood agar, McConkey agar and Cysteine Lactose Electrolyte Defficient Agar, for the presence of pathogenic bacteria. The isolated organisms were subjected to biochemical tests for identification using standard procedures. The isolates were screened for Extended Spectrum β-lactamase (ESBLs) production using the Clinical Laboratory Standard Institute (CLSI) break point using ceftriazone (30µg) and cefotaxime (30µg). Suspected ESBLs producing organisms from screening tests were subjected to double disc synergy test (DDST) for confirmation and standard discs of Augmentin (30µg). Out of the 144 snack samples analysed, 24 Gram negative entericbacteria were isolated and these includes: Citrobacter freundii 6(25%), Echerichia coli 1(4.2%), Enterobacter sp. 2(8.3%), Klebsiella pneumonia 7(29.2%), Proteus mirabilis 1(4.2%), Serratia marcenscens 4(16.7%), Morganella morganii 1(4.2%), providencia sp. 1(4.2%) and Shigella sp. 1(4.2%). Detection of ESBL among Gram-negative isolates based on CLSI revealed that 16(66.7%) of the isolates were ESBL producers while 37.5% were confirmed as ESBLs producers using Double Disc Synergy Test. Statistically, there was a significant relationship between the different beta-lactamases producing isolates (P<0.05). It also showed a significant relationship between the occurrences of beta-lactamase producing isolates among the different snacks (P<0.05) This study indicated that snack foods can be contaminated by ESBLs producing bacteria and may result to infections following consumption by humans which have public health implications for the general public.

SUSHI: RISCO MICROBIOLÓGICO?

A presença de estafilococos coagulase positiva e coliformes a 45ºC em alimento que será consumido cru representa potencial risco à saúde do consumidor. Buscou-se averiguar a presença de bactérias pertencentes aos grupos dos estafilococos e coliformes em sushis confeccionados à base de salmão comercializados em Parnaíba/PI. Foram realizadas análises para determinar as contagens de Bactérias Heterotróficas Cultiváveis (BHC), estafilococos coagulase positiva e NMP de coliformes a 45ºC. Os resultados foram comparados aos limites aceitáveis pela RDC nº 12 de 2001 (ANVISA). As contagens de BHC variaram de 1,3 x 10 5 a 4,0 x 10 7 UFC/g e 4,6 x 10 4 a 2,2 x 10 5 UFC/g para os estabelecimentos A e B. As contagens de estafilococos coagulase positiva para as amostras coletadas no estabelecimento A indicaram níveis acima do permitido e ausência para o estabelecimento B. A presença de coliformes a 45ºC foi confirmada para os dois estabelecimentos, no entanto, 25% das amostras do estabelecimento B expressaram níveis acima do permitido. O presente estudo demonstra o risco microbiológico em sushi preparado à base de salmão cru ao confirmar a presença de bactérias patogênicas em concentrações acima do permitido pela legislação nacional vigente.

How host regulation of Helicobacter pylori-induced gastritis protects against peptic ulcer disease and gastric cancer.

The bacterial pathogen Helicobacter pylori is the etiological agent of a range of gastrointestinal pathologies including peptic ulcer disease and the major killer, gastric adenocarcinoma. Infection with this bacterium induces a chronic inflammatory response in the gastric mucosa (gastritis). It is this gastritis that, over decades, eventually drives the development of H. pylori-associated disease in some individuals. The majority of studies investigating H. pylori pathogenesis have focused on factors that promote disease development in infected individuals. However, an estimated 85% of those infected with H. pylori remain completely asymptomatic, despite the presence of pathogenic bacteria that drive a chronic gastritis that lasts many decades. This indicates the presence of highly effective regulatory processes in the host that, in most cases, keeps a check on inflammation and protect against disease. In this minireview we discuss such known host factors and how they prevent the development of H. pylori-associated pathologies.

Comparison of Microbiological and Physicochemical Quality of Tap and Dispenser Water from Different Mid-Range Restaurants of Dhaka City, Bangladesh

Dhaka is the most populous city in Bangladesh and the tenth-largest metropolitan in the world with about twelve million inhabitants. Most people of Dhaka have low or middle ranged incomes and frequently use roadside mid range restaurants to take their meals and drinking water. Water quality is a significant health concern in Bangladesh and is a probable source of many water borne diseases and outbreaks. Tap water and dispenser water samples were collected from ten roadside restaurants. These samples were analyzed for pH, salinity, conductivity, TDS (total dissolved solid) for physicochemical quality analysis while total coliform, faecal coliform and total heterotrophic bacterial counts were determined for microbiological quality analysis. All the samples conformed to the WHO standards of TDS, salinity and conductivity. Except for 20% of the tap water samples, pH of all the samples was found to be satisfactory. The heterotrophic plate count was in a range of 8.0 x 101 cfu/ml to 9.3 x 105 cfu/ml from tap water sample and 6.5 x 101 cfu/ml to TNTC from dispenser water samples. Only 10% of the tap water samples and 30% of the dispenser water samples complied with the WHO stipulated limit of total heterotrophic count (100 cfu/ml). In terms of total coliforms, all the tap water samples and 20% of the dispenser water samples were found to be contaminated, whereas 50% of both the tap water and dispenser water samples were contaminated with faecal coliforms, indicating possible faecal contamination and presence of pathogenic bacteria. By comparing coliform/faecal coliform count on tap and dispenser water it was found that dispenser water is safer than tap water.Bangladesh J Microbiol, Volume 31, Number 1-2,June-Dec 2014, pp 69-72

Metagenomic analysis of bacterial community composition and antibiotic resistance genes in a wastewater treatment plant and its receiving surface water

The presence of pathogenic bacteria and the dissemination of antibiotic resistance genes (ARGs) may pose big risks to the rivers that receive the effluent from municipal wastewater treatment plants (WWTPs). In this study, we investigated the changes of bacterial community and ARGs along treatment processes of one WWTP, and examined the effects of the effluent discharge on the bacterial community and ARGs in the receiving river. Pyrosequencing was applied to reveal bacterial community composition including potential bacterial pathogen, and Illumina high-throughput sequencing was used for profiling ARGs. The results showed that the WWTP had good removal efficiency on potential pathogenic bacteria (especially Arcobacter butzleri) and ARGs. Moreover, the bacterial communities of downstream and upstream of the river showed no significant difference. However, the increase in the abundance of potential pathogens and ARGs at effluent outfall was observed, indicating that WWTP effluent might contribute to the dissemination of potential pathogenic bacteria and ARGs in the receiving river.

Isolation and quantification of microorganisms from some common milk products within Dhaka city, Bangladesh

While milk is well known to be a balanced diet with its high nutritional values, conversely milk and milk products may serve as potential substrate for the growth and proliferation of a range of microorganisms which in turn fatally influences mass public health. Current study attempted to examine the likelihood of microbial contamination within some common milk products consumed by the locality of the city of Dhaka, Bangladesh. All samples exhibited the presence of bacterial and fungal contamination within a range of 102-104 cfu/mL and 102-103 cfu/mL, respectively. Among specific pathogens, Staphylococcus spp. was noticed to be the predominant ones and was recovered from 9 samples out of 20 samples in a range of 102-103 cfu/mL. Klebsiella spp. and Vibrio spp. were found within 6 and 9 samples, respectively. Products were also found to be contaminated with Vibrio spp. Study of antibiotic susceptibility test revealed that all the pathogenic bacteria were resistant against most of the commonly used antibiotics of which several isolates showed multi-drug resistant (MDR) trait. Therefore, the presence of pathogenic bacteria with the drug-resistance property in tested milk and milk products overall imparted the necessity of maintaining standardized hygienic handling and processing means for better management of public health.Stamford Journal of Microbiology, Vol.5(1) 2015: 13-17

Oxidative Damage Caused by Common Foodborne Pathogenic Bacteria in Egg Yolk

Background: Bacteria in foodstuff are the most important agent of foodborne disease. Aside from their infectious effects, obligate aerobes have a respiratory metabolism with oxygen as the terminal electron acceptor. Therefore, they can produce reactive oxygen species and free radicals in contaminated food. Malondialdehyde (MDA) is a product of lipid peroxidation used as an indicator of oxidative stress. Objectives: This study aimed to evaluate the oxidative damage produced by two common food pathogenic bacteria in foodstuff. Materials and Methods: The egg yolks were incubated with different dilutions (10 5 ,10 6 , and 10 7 ) of Staphylococcus aureus and Salmonella enteritidis at 37°C for 20 hours. The level of MDA in egg yolk was measured by fast and simple enzymatic or colorimetric methods, such as the thiobarbituric acid reactive species method. Results: The high group (10 7 ) had a higher MDA level of 1.97 ± 0.11 (µg MDA/g) in S. aureus and 1.65 ± 0.27 (mg MDA/L) in S. enteritidis than the control (0.90 ± 0.13 mg MDA/L). Conclusions: We concluded that common food pathogenic bacteria can induce oxidative damage in foodstuff aside from other common problems. Heating or sterilization methods cannot protect foodstuff from the damage caused by the presence of pathogenic bacteria.

Reduction of microbial risk associated with greywater by disinfection processes for irrigation.

Greywater is one of the most important alternative sources for irrigation in arid and semi-arid countries. However, the health risk associated with the microbial contents of these waters limits their utilization. Many techniques have been developed and used to generate a high microbiological quality of greywater. The main problem in the treatment of greywater lies in the nature of pathogenic bacteria in terms of their ability to survive during/after the treatment process. The present review focused on the health risk associated with the presence of pathogenic bacteria in greywater and the treatment technologies used for the disinfection processes.

Microbiological quality of fresh produce obtained from retail stores on the Eastern Shore of Maryland, United States of America

The aim of this study was to investigate the microbiological quality of six types of fresh produce obtained from three retail stores located on the Eastern Shore of Maryland, USA. A total of 414 samples representing basil, cilantro, lettuce, scallion, spinach, and parsley were analyzed for total aerobic bacteria (APC), total coliforms, Escherichia coli, and three pathogenic bacteria (E. coli O157:H7, Listeria monocytogenes, and Salmonella), using standard methods. Presumptive pathogenic isolates were confirmed using BAX Polymerase Chain Reaction. Total aerobic populations varied widely between samples, while 38.41% were positive for total coliforms and only 10.15% for E. coli. Median abundance (log CFU/g) of total coliforms and E. coli were less than the limit of detection and that of APC ranged from 5.78 to 6.61 over the six produce types. There was a statistically significant difference in prevalence of total coliforms among the retail stores, but not for abundance of APC or prevalence of E. coli. E. coli O157:H7 and L. monocytogenes were detected in one spinach sample each, while one parsley and one cilantro sample were positive for Salmonella. There were no statistically significant differences in microbiological quality among produce types. Although the results of this study provided some indices of sanitary and/or spoilage level, no relationship was observed among the total aerobic bacteria, total coliforms, E. coli, and the presence of pathogenic bacteria in the samples tested.