Sulfite-reducing Bacteria Research Articles

Socio-sanitary Aspects and Microbiological Quality of Drinking Water in the Prefecture of Golfe (Togo)

Water is essential for life, but its quality is confronted with several problems, including insufficient hygiene and sanitation, which necessitate a contribution to improving the hygienic quality of drinking water. Adescriptive study of 129 randomly selected households was carried out in order to get an idea of the health risks associated with drinking water. Water samples (75) were analyzed using the standardized routine methods described by the European Union. These analyzes related to the following germs: total aerobic flora, total coliforms, thermo tolerant coliforms, Escherichia coli, anaerobic sulfite-reducing bacteria and fecal streptococci. The results showed that 43.41% of households surveyed do not have a source of water at home. Water sources include wells, boreholes, and rainwater. Drinking water storage containers are not covered in 38.89% of the cases. Of the 60 households that have a water source and a latrine at the same time, 27 households or 45% have latrines within 15 meters of the water source. The microbiological analyzes showed that the drinking water samples analyzed are contaminated to varying degrees by the germs retained by the European Union criteria. Total germs and coliforms resulted in high levels of non-compliance. The waters of the storage containers were the most contaminated. Appropriate measures shall be taken for the monitoring and disinfection of these waters before their use.

Bacteriological and geochemical features of the groundwater resources: Kettara abandoned mine (Morocco)

Waste water of the Kettara village, as well as the abandoned tailings, constitute a potential environmental issue with direct consequences on air, soil, water resources qualities and, on human health. In this paper, experimental investigations examine the environmental impact which is induced by the wastewater, mine tailings and the lithological factors of rocks. This multidisciplinary research allows to i) understand the transfer of the Metallic Trace Elements (selenium, arsenic, nickel and zinc) and sulfate ions in the fractured shales media, ii) to assess the water potability by using the microbiological analysis. The microbiological results reveal the domestic impact by the presence of several kinds of bacteria in the groundwater resources: E. coli, Fecal coliforms, Total coliforms, Enterococci, Mesophilic Aerobic Flora, Sulphite-reducing bacteria and Salmonella.Selenium, arsenic and the bacteriological contamination of the groundwater could be explained by five kinds of factors: i) the geological formations and the nature of the hydrogeological system (unconfined layer), ii) the groundwater flow, the hydraulic relation between the hydrogeological wells and, the fractures network in the shale aquifer. The piezometric map allows to highlight the groundwater flow from the North-East to North-West and to the South-West, the drainage axis towards the P21 well and the presence of the dividing axis in the contaminated zone by the arsenic, iii) the absence of the unhealthy habitats with permeable traditional septic tanks in the village; iv) the transfer of the spreading animal excrements from the soil to groundwater and, v) the migration of the wastewater towards downstream of the groundwater flow. The presence of the reed beds could explain the reduction of bacteria in the hydrogeological wells of the study area.

The Microbiome in Functional Gastrointestinal Disorders Is Characterized by Bacteria and Genes Involved in Carbohydrate and Bile Acid Metabolism (OR23-01-19)

ObjectivesIrritable Bowel Syndrome (IBS) is a functional gastrointestinal (GI) disorder featuring chronic or recurrent abdominal discomfort, usually with changes in GI habit. To improve our understanding of links between the microbiome and IBS, and how these links can be manipulated through diet, we undertook shotgun metagenomic sequencing of fecal samples from a case-control study. MethodsFecal samples from 172 individuals were analyzed by shotgun sequencing using the Illumina NextSeq platform. Of these, 77 were classified as controls, 16 were constipation-predominant IBS (IBS-C), 39 were diarrhea-predominant IBS (IBS-D), 29 were diagnosed with functional constipation (FC), and 11 had functional diarrhea (FD). Taxonomic classifications were determined using Metaxa2 and the SILVA 128 database. Gene functions were assigned by alignment of sequences against a protein reference database using DIAMOND. Mean relative abundance of bacterial taxa and functional genes were compared using permutation ANOVA. Ethical approval was obtained from the University of Otago Human Ethics Committee (Health) (Reference H16/094). ResultsBacterial genera that discriminated case-controls (P < 0.05) from those with constipation (IBS-C + FC) and diarrhea (IBS-D + FD) included Megasphaera (increased in those with constipation), Blautia (increased in those with diarrhea), and Bilophila (increased in both constipation and diarrhea groups). Megasphaera and Blautia include bacteria that are bile-resistant and produce butyrate, possessing a wide range of Carbohydrate-Active enzymes. Bilophila are sulfite-reducing bacteria that are able to utilize bile-acids. Associated with these taxonomic differences, a wide range of genes involved in carbohydrate, energy, and amino acid metabolism differed significantly (P < 0.05), including some involved in taurine and glycine metabolism. Bile acids are conjugated with taurine or glycine in the liver, and these amino acids are removed by the action of members of the GI microbiota. ConclusionsResults from our study suggest carbohydrate and bile acid metabolism by the GI microbiome may be important distinguishing characteristics in functional GI disorders. Funding SourcesFunded by the New Zealand National Science Challenge High-Value Nutrition program.

Radical-mediated C-S bond cleavage in C2 sulfonate degradation by anaerobic bacteria

Bacterial degradation of organosulfonates plays an important role in sulfur recycling, and has been extensively studied. However, this process in anaerobic bacteria especially gut bacteria is little known despite of its potential significant impact on human health with the production of toxic H2S. Here, we describe the structural and biochemical characterization of an oxygen-sensitive enzyme that catalyzes the radical-mediated C-S bond cleavage of isethionate to form sulfite and acetaldehyde. We demonstrate its involvement in pathways that enables C2 sulfonates to be used as terminal electron acceptors for anaerobic respiration in sulfate- and sulfite-reducing bacteria. Furthermore, it plays a key role in converting bile salt-derived taurine into H2S in the disease-associated gut bacterium Bilophila wadsworthia. The enzymes and transporters in these anaerobic pathways expand our understanding of microbial sulfur metabolism, and help deciphering the complex web of microbial pathways involved in the transformation of sulfur compounds in the gut.

Evaluation of the Microbiological Quality of Different Moroccan Drinking Water in the Beni Mellal Region

Drinking water is water that does not contain pathogens or chemicals at levels that may be harmful to health. Beni Mellal region, one of the major rich areas in ground and surface water in Morocco (the rivers like Oum Errabia, Darna, ...; Bin el-Ouidane and martyr Ahmed El Hansali dams and sources like Ain Asserdoune, …) is located in the North-Centre of Morocco. The main objective of the present study was to evaluate the microbiological quality of different drinking waters originated from sources, faucets, fountains and wells in the Beni Mellal city and its agricultural surrounding areas. For this, hygienic quality indicator parameters of water quality were determined by assessing the analysis of Total Coliforms Count, Fecal Coliforms Count, streptococcus D and revivable germs while germs such as Anaerobic Sulphite-reducing Bacteria, S. aureus and Salmonella sp, were carried out according to national and international standards. The analysis of the microbiological results found for all the different samples waters investigated in this study revealed that the waters originated from fountains, faucets and sources were proper for main consumption at microbiological point of view while the wells waters were improper for consumption according to norms. Finally, it appears, from the results obtained, that the potential risk of infection of water consumers especially (groundwater) calls for prompt intervention in order to alleviate the potential health impact of water-borne diseases in the community. From this, a proper sanitary survey and implementation of water and sanitation projects in the community is recommended.

Genomic Characterization of Sulphite Reducing Bacteria Isolated From the Dairy Production Chain.

Anaerobic sporeformers, specifically spoilage and pathogenic members of the genus Clostridium, are a concern for producers of dairy products, and of powdered dairy products in particular. As an alternative to testing for individual species, the traditional, and still current, approach to detecting these sporeformers, including non-spoilage/non-pathogenic species, in dairy products has involved testing for a sulphite reducing phenotype [Sulphite reducing Clostridia (SRCs)] under anaerobic conditions. This phenotype is conserved throughout the Order Clostridia. Unfortunately, however, this phenotype is exhibited by other sulphite reducing bacteria (SRBs) also, potentially leading to potential for false positives. Here, this risk was borne out through the identification of several SRBs from industry samples that were identified as Proteus mirabilis and various Bacillus/Paenibacillus sp. Genome wide comparison of a number of representative SRCs and SRBs was employed to determine phylogenetic relationships, especially among SRCs, and to characterize the genes responsible for the sulphite reducing phenotype. This screen identified two associated operons, i.e., asrABC in SRCs, and cysJI in Bacillus/Paenibacillus spp. and P. mirabilis. This screen identified spp. belonging to sensu stricto, Lachnospiraceae and Cluster XIV of the Clostridia all producing the SRC phenotype. This study highlights the inaccuracy of the industry standard SRC test but highlights the potential to generate an equivalent molecular test designed to detect the genes responsible for this phenotype in clostridia.

Kebab: can the traditional cooking process sanitize a natural contamination by Listeria monocytogenes?

Over the last few years a considerable spread of ethnic foods was observed in Italy. Among them is the Döner kebab. During 2014-2015, in order to evaluate the effectiveness of traditional cooking process, raw product (defrosted), sliced cooked portions cut through electric knife and assembled sandwich were officially sampled in kebab houses and in a local industrial kebab producer in Reggio Emilia (a province in Italy). Microbiological researches for safety and hygienic microbiological indicators were carried out (research of Salmonella, Listeria monocytogenes, Campylobacter and Shiga toxin-producing Escherichia coli; enumeration mesophilic aerobic bacteria, lactic acid bacteria, sulfite-reducing bacteria growing under anaerobic conditions, yeasts and molds). Between the raw and the cooked product an average of 3 log reduction in mesophilic aerobic bacteria counts was observed. In two out of three kebab houses sampled, which were supplied by the same local industrial producer, the presence of L. monocytogenes was detected. During the official inspection carried out at the production plant a contamination of L. monocytogenes was assessed in both ambient and instruments. Furthermore, 3 lots of products were analyzed and all were found to be contaminated by L. monocytogenes (always above 100 CFU/g). In order to verify the capability of the traditional cooking process to reduce the risk of contamination at an acceptable level, a batch of naturally contaminated kebab (4.5 log CFU/g) was cooked and sliced simulating a day work activity in a kebab shop. The product was then sampled during preparation and enumeration of L. monocytogenes was obtained. After an hour of cooking, the residual contamination was 1.8 log CFU/g, after two hours and a half L. monocytogenes was no longer detectable in the product, but half an hour later it was again detectable in 25g. At the end of the experiment, the contamination grown up to the same level enumerated after an hour of cooking (1.8 log CFU/g). Considering the microbiological results, traditional cooking obtained a rate of -2.40 log CFU/gh-1, a D=26 min that corresponds to a temperature of maximum 60°C (z=6). In conclusion, our experiment demonstrates the traditional kebab cooking process could not always guarantee a complete product decontamination.

Hyperbaric cold storage: Pressure as an effective tool for extending the shelf-life of refrigerated mackerel (Scomber scombrus, L.)

Abstract The efficacy of hyperbaric cold storage for preserving lean fish has been recently demonstrated but, to the best of our knowledge, no data exist for fatty fish. To evaluate the effect of hyperbaric cold storage on the shelf-life and quality of fatty fish, we stored Atlantic mackerel fillets at 5 °C, both at atmospheric pressure and at 50 MPa. After 12 days of hyperbaric storage, no microbial growth was observed. Thus, most counts were similar or slightly lower than those of control samples at day 0, while H2S-producing organisms and sulphite-reducing bacteria reduced under the detection limits. Moreover, no significant lipid degradation was observed. By contrast, increased microbial counts and significant lipid hydrolysis were detected in the samples stored at atmospheric pressure. Moreover, even though the protein profile was significantly altered during hyperbaric storage, most fish-quality indicators (pH, TVB-N, drip loss, water-holding capacity, and firmness after cooking) were better preserved in the mackerel samples stored at 50 MPa. These results clearly prove that hyperbaric cold storage was more efficient than conventional refrigeration for the preservation of Atlantic mackerel fillets. Industrial relevance Long-term preservation of fatty fish is a challenge for the seafood industry mainly due to lipid degradation that can rapidly reduce fish quality. If effective against lipid degradation, hyperbaric cold storage could be an interesting technology to preserve fish and fish products. The increased cost resulting from hyperbaric storage should be overcome by an extended shelf-life of a high-quality product.

Influence of probiotic (Lactobacillus acidophilusNCFM,L. paracaseiLPC37, andL. rhamnosusHN001) strains on starter cultures and secondary microflora in Swiss- and Dutch-type cheeses

The aim of this study was to determine the influence of three probiotic strains on microbial quality of industrially produced Swiss- and Dutch-type cheeses. The levels of starter cultures were higher in Swiss-type cheeses containing L. paracasei LPC37 and L. rhamnosus HN001. Mesophilic citrate-fermenting bacteria were more abundant in cheeses containing L. acidophilus NCFM. The greatest reduction in Propionibacterium sp. counts was observed in cheeses produced with the addition of L. paracasei LPC37. All adjunct Lactobacillus sp. cultures stimulated changes in Enterococcus sp. counts and significantly influenced the counts of yeasts and molds in cheeses. Populations of coliform bacteria were lower in experimental cheeses than in control cheeses. The counts of butyric acid bacteria and anaerobic sulfite-reducing bacteria were reduced in experimental Swiss-type cheeses. Lactobacillus sp. used in the study are characterized by good viability and have no negative influence on starter cultures in cheese production. Practical applications Effect of three Lactobacillus sp. strains on technologically harmful microflora in cheeses. The protective (antibacterial) effect of bacteria depends on the type of cheese, temperature of ripening and storage, and the applied strain.

Bacteriological analysis and public perception about drinking water of boreholes in Arib (Ain Defla, Algeria)

Water from boreholes in Arib (Ain Defla), south-west of Algeria was investigated to ascertain its quality status and suitability for drinking and domestic uses. Fifty six water samples were collected from four boreholes. The analyses of the Coliform counts obtained from various boreholes samples ranged between 0 and 200 CFU/ 100 ml with regard to total Coliforms and between 0 and 8 CFU/ 100 ml with regard to fecal Coliforms. Three of the boreholes samples showed contamination by Streptococcus sp. Pathogens like Salmonella were not identified but some low levels of sulfite-reducing bacteria was found. The interviews were done to assess perceptions on water taste problems, odour, colour, and turbidity and health problems. The respondents were taken from people in the community using random sampling technique. Sixty people were sampled at each area surrounding the boreholes. It was found out that 43.3% of the respondents rated their drinking water safe for consumption as well as absence of illness after drinking as indicators for judging the quality of the water. The others respondents (56.7%) reported having at least some concerns with safety of their water. More than 20% of the households reported at least one household member having suffered some water related illness in the past two years. Respondents were asked to judge the quality of the water, based on four sensory characteristics of drinking water. Many respondents rated the smell (33.3%), taste (20%), colour (23.3%) and turbidity (23.3%). These results showed that all the samples did not satisfy the WHO requirements for bacteriological characteristics in human consumption.

Using microbiological tracers to assess the impact of winter land use restrictions on the quality of stream headwaters in a small catchment

Diverse land use activities can elevate risk of microbiological contamination entering stream headwaters. Spatially distributed water quality monitoring carried out across a 17km2 agricultural catchment aimed to characterize microbiological contamination reaching surface water and investigate whether winter agricultural land use restrictions proved effective in addressing water quality degradation. Combined flow and concentration data revealed no significant difference in fecal indicator organism (FIO) fluxes in base flow samples collected during the open and prohibited periods for spreading organic fertilizer, while relative concentrations of Escherichia coli, fecal streptococci and sulfite reducing bacteria indicated consistently fresh fecal pollution reached aquatic receptors during both periods. Microbial source tracking, employing Bacteroides 16S rRNA gene markers, demonstrated a dominance of bovine fecal waste in river water samples upstream of a wastewater treatment plant discharge during open periods. This contrasted with responses during prohibited periods where human-derived signatures dominated. Differences in microbiological signature, when viewed with hydrological data, suggested that increasing groundwater levels restricted vertical infiltration of effluent from on-site wastewater treatment systems and diverted it to drains and surface water. Study results reflect seasonality of contaminant inputs, while suggesting winter land use restrictions can be effective in limiting impacts of agricultural wastes to base flow water quality.

Application of bootstrap method to evaluate bimodal data: an example of food microbiology proficiency test for sulfite-reducing anaerobes

Statistical analysis has an essential role in proficiency test (PT) evaluation, especially when the distribution of results of the enumeration of microbiological bacteria is multimodal or strongly asymmetric, outliers aside. In these specific cases, the median or the robust mean of the PT results, calculated using the algorithm described in ISO 13528 Annex C, is not entirely appropriate for estimating the assigned value. A possible solution is to estimate the modes of kernel density function of data distribution and its uncertainty by using the nonparametric bootstrap technique. This method allows estimation of the sampling distribution of a statistic empirically without making assumptions about the form of the population. In the context of the PT for the enumeration of sulfite-reducing bacteria growing under anaerobic conditions organized in 2012 by QUAlity Assurance, although all participants used equivalent methods, the results showed high variability, which supported the hypothesis that two discrepant populations occurred in the test samples. When a bimodal distribution occurs, it is reasonable to suppose that at least one of the modes could be correct, but unless independent grounds for preferring one over the other are available, it is not possible to determine the assigned value and calculate the z-score. In the case of the sulfite-reducing bacteria PT, the true mode was not identified and the performance evaluation was not provided. For this reason, the PT provider (IZSVe) asked that the participants report every unusual situation for this test, should they occur during the next PTs. In this way, it may be possible to identify a plausible assigned value and its uncertainty as bootstrap mode of kernel density and standard error, respectively, and to provide the z-score as value of performance evaluation in the case of negligible uncertainty.

Microbiological safety of pastrami: A traditional meat product

Pastrami is a traditional and popular meat product which is produced from whole muscle obtained from beef carcasses. Consumers prefer pastrami produced by small scale firms or local butchers, as a result of common estimation about homemade products are healthier and more nutritive than processed pastrami. In this study, it was aimed to investigate the microbiological quality of pastrami samples traditionally produced in Tokat with unstandardized methods and to evaluate the results in the context of food safety. All the samples were analyzed for total mesophilic aerobic bacteria, lactic acid bacteria, coagulase-positive staphylococci, sulphite-reducing bacteria, yeasts and molds, Escherichia coli, Salmonella spp. and Listeria monocytogenes. Titratable acidity, pH and water activity values were determined to evaluate the microbiological test results. The results of microbiological analyses were higher than the limits in the legislation and the samples were not microbiologically safe for consuming. Unstandardized and uncontrolled process conditions are the main reasons for the microbiological risks. When the increasing consumer demand for traditional foods is considered, the safety of the traditional product, should be the primary and plenary parameter and it could be managed with standardized production methods and appropriate sanitation conditions.

Maiorchino Cheese: Physico-Chemical, Hygienic and Safety Characteristics.

This study assessed the physical, chemical, and microbiological characteristics of traditional Maiorchino cheese (Italy) made from raw ewe’s milk or from a mixture with goat’s milk. Cheese samples from the same batch were analyzed after 20 days and 6, 8, 12, 17 and 24 months of ripening. A decrease in moisture level lead to progressive total solids concentration (fat, total nitrogen, total solids and chloride) during ripening. Aw values decreased from 0.97 (day 20) to 0.85 (month 24), while pH increased from 4.99 to 5.41 (6 months) followed a by reduction until 4.85 (month 24). In samples analysed 20 days after cheesemaking, aerobic mesophilic count was 1.8•107 CFU/g, Enterobacteriaceae were 2.7•106 CFU/g, Staphylococcus spp. were 1.8•104 CFU/g, and yeasts 4.5•105 CFU/g. Sulphite reducing bacteria were not found. Lactic bacteria count at 30°C (LAB30) and 42°C (LAB42) was about 108 CFU/g (day 20); LAB30 reduced until month 8; LAB 42 reduced until month 12; both were not detectable at months 17 and 24. Cheese-making process does not consider commercial starter cultures and LAB group is heterogeneous because of its natural microflora. Yeasts were considered as typical microflora of Maiorchino. Volatile compounds were examined at 6, 12 and 24 months of ripening; 54 components were identified. Statistical analysis showed that the seasoning period of 12 months was the best for Maiorchino flavour attributes. The characterisation of Maiorchino traditional cheese may be considered as significant for this old traditional product, with the aim of obtaining the PDO certification.

Physicochemical, Bacteriological, and Radiochemical Characterization of Some Algerian Thermal Spring Waters

Hot springs have been known for a long time over the world. They are used for curative action and healing properties linked to their physical and chemical characteristics. In order to best use the opportunities provided by globalization, Algerian authorities try to modernize its social and economic policies investing mainly in geothermal resources recognizing that the hot springs have rich potential to develop ecotourism. Nevertheless, the use of thermal waters requires nowadays a prior characterization to study their quality. The mineral bacteriology assessment Type 0, Type 1, and Type 2 are used to assess the microbiological quality. It consists of the enumeration of total aerobic flora (37 $$^{\circ }\hbox {C})$$ , Coliforms and Escherichia coli, intestinal enterococci, sulphite-reducing bacteria spores, Pseudomonas aeruginosa, Legionella and pathogenic staphylococci using standard microbiological techniques and culture method. The sixteen thermal springs mainly from the eastern part of Algeria, whose water temperature ranges between 39 and 93 $$^{\circ }\hbox {C}$$ , were also subjected to hydrochemical and gamma spectrometric methods. The obtained results showed the average number of total aerobic flora ranging from 0 to $$4\times 10^{4}$$ CFU/mL and the presence of Staphylococcus aureus species. Four springs revealed the presence of Legionella. Two springs among the four also exhibited a significant contamination by enterococci. The conductivity ranged from 296 to 48,100 $$\upmu $$ S/cm. The thermal waters are rich in minerals representing the evaporite deposits leaching with high temperatures and significant mineralization in both major and minor elements. Measured activities of $$^{40}$$ K ranged from 360 to 6,330 mBq/L. For the $$^{238}\hbox {U}$$ series, $$^{226}\hbox {Ra}$$ activity concentrations varied from 8 to 6,110 mBq/L. Activity concentrations determined for $$^{137}\hbox {Cs}$$ revealed that only one thermal spring contained this radionuclide with concentration of 95 mBq/L.

Detection of pathogenic clostridia in biogas plant wastes.

As the number of biogas plants has grown rapidly in the last decade, the amount of potentially contaminated wastes with pathogenic Clostridium spp. has increased as well. This study reports the results from examining 203 biogas plant wastes (BGWs). The following Clostridium spp. with different frequencies could be isolated via a new enrichment medium (Krüne medium) and detected by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS): Clostridium perfringens (58%) then Clostridium bifermentans (27%), Clostridium tertium (23%) and Clostridium butyricum (19%), Clostridium cadaveris (15%), Clostridium parapurificum (6%), Clostridium glycolicum (5%), Clostridium baratii (4%), Clostridium sporogenes (2 %), Clostridium sordellii (1%) and Clostridium subterminale (0.5%). The mean most probable number (MPN) count of sulfite reducing bacteria was between 10(3) and 10(4)/mL, and the higher the MPN, the more pathogenic Clostridium spp. were present. Also, real-time PCR was used to be compared with culture method for C. perfringens, C. bifermentans, C. butyricum, C. sporogenes/Clostridium botulinum and C. sordellii. Although real-time PCR was more sensitive than the culture method, both systems improve the recovery rate but in different ways and are useful to determine pathogenic clostridia in biogas plants. In conclusion, BGWs could present a biohazard risk of clostridia for humans and animals.

Correlation between Specific Bacterial Groups in the Oral Cavity and the Severity of Halitosis: Any Possible Beneficial Role for Selected Lactobacilli?

Objective: Halitosis is a widespread problem, normally attributable to specific volatile sulphur compounds (VSC) in the breath. The aim of this study was to first relate halitosis with possible gastric infection by Helicobacter pylori and secondly to quantify specific bacterial groups in the oral cavity flora, thus correlating them with VSC concentrations and Proton Pump Inhibitors (PPIs) intake. Four selected lactobacilli were then assessed in the possible reduction of halitosis in subjects with a total salivary bacterial concentration higher than 105 CFU/ml. Methods: Specific bacterial groups, namely total bacteria, total coliforms, sulphite-reducing bacteria (SRB) and lactobacilli, were quantified in samples of saliva from 29 subjects taking PPIs compared with 36 control subjects. The amount of the three VSC hydrogen sulfide (H2S), methyl mercaptan (CH3SH) and dimethyl sulfide (CH3)2S in the breath and the presence of H. pylori were determined. Results: No significant correlation was found between H. pylori and halitosis as well as with PPIs intake. The baseline bacterial groups quantification (log10 CFU/ml of saliva, PPI group vs. control) showed: total bacteria 8.44 vs. 4.47 (p=0.001); total coliforms 4.95 vs. 2.82 (p=0.001); sulfite-reducing bacteria 5.47 vs. 2.58 (p=0.052); total lactobacilli 4.00 vs. 2.36 (p=0.016). After 15 days of lactobacilli supplementation, the same parameters (d15 vs baseline) gave: total bacteria 7.92 vs. 8.44 (p=0.019); total coliforms 3.13 vs. 4.95 (p=0.001); sulfite-reducing bacteria 4.69 vs. 5.47 (p=0.047); total lactobacilli 7.86 vs. 4.00 (p=0.048). No statistically significant differences were noted in VSC concentrations at any time. Conclusions: The intake of PPIs directly correlated with the overgrowth of specific bacterial groups in the oral cavity, but there was no correlation with H. pylori or with VSC concentration. The significant reduction in all the bacterial groups analysed after two weeks suggested the improvement of the overall oral flora in subjects chronically treated with PPIs.

Endospore recovery from large volumes using fieldable ultrafiltration for the diagnosis of drinking water treatment plants

Anaerobic sulfite-reducing and aerobic spore-forming bacteria are used as indicators to verify the reliability of water treatment plant efficiency. The objectives of this study aimed to highlight the more accurate endospore indicator for water treatment monitoring and to select an efficient filtration system in order to detect low amounts of endospores from large volumes. The performance of two different ultrafiltration modules was assessed with two filtration configurations (tangential and dead-end). The Hemoflow™ and the Dizzer® filters present recovery yields of 73% and 77% for 100-liter samples of drinking and sand filtered water, respectively. Both systems enabled detection of endospores at a concentration level of 100 spores in 100 liters, by analyzing the totality of the volume, whereas the standard method did not highlight the presence of spores, analyzing only 100 mL subsamples. In addition, experiments on a sand filtration pilot confirmed that the concentration calculation using the standard method is not reliable, due to extrapolation from the small volumes analyzed. This study highlights that the collection of large volumes using a fieldable dead-end hollow-fiber ultrafiltration system in association with the detection of anaerobic sulfite-reducing spore-forming bacteria is an effective way to monitor drinking water production.

Bile Acids as Modulators of Gut Microbiota Linking Dietary Habits and Inflammatory Bowel Disease: A Potentially Dangerous Liaison

Bile Acids as Modulators of Gut Microbiota Linking Dietary Habits and Inflammatory Bowel Disease: A Potentially Dangerous Liaison

Preliminary quality assessment of bovine colostrum

Data on bovine colostrum quality are scarce or absent, although Commission Regulations No 1662/2006 and No 1663/2006 include colostrum in the context of chapters on milk. Thus the aim of the present work is to study some physical, chemical, hygiene and safety quality parameters of bovine colostrum samples collected from Sicily and Calabria dairy herds. Thirty individual samples were sampled after 2-3 days from partum. The laboratory tests included: pH, fat (FT), total nitrogen (TN), lactose (LTS) and dry matter (NM) percentage (Lactostar) and somatic cell count (CCS) (DeLaval cell counter DCC). Bacterial counts included: standard plate count (SPC), total psychrophilic aerobic count (PAC), total, fecal coliforms by MPN (Most Probable Number), sulphite-reducing bacteria (SR). Salmonella spp. was determined. Bacteriological examinations were performed according to the American Public Health Association (APHA) methods, with some adjustements related to the requirements of the study. Statistical analysis of data was performed by Spearman’s rank correlation coefficient. The results showed a low variability of pH values and FT, TN and DM percentage between samples; whereas LTS trend was less noticeable. A significant negative correlation (P<0.01) was observed between pH, TN and LTS amount. The correlation between LTS and TN contents was highly significant (P<0.001). Highly significant and negative was the correlation (P<0.001) between DM, NT and LTS content. SPC mean values were 7.54 x106 CFU/mL; PAC mean values were also high (3.3x106 CFU/mL). Acceptable values of coagulase positive staphylococci were showed; 3 Staphylococcus aureus and 1 Staphylococcus epidermidis strains was isolated. Coagulase negative staphylococci counts were low. A high variability in the number of TC, as for FC was observed; bacterial loads were frequently fairly high. Salmonella spp. and SR bacteria were absent. It was assumed that bacteria from samples had a prevailing environmental origin; colostrum was also subject to a fecal contamination, frequently found in samples. The majority of samples had a high SCC, probably for a stress situation during cows birth. Statistical analysis showed a highly significant correlation (P<0.001) between SPC and PAC. Faulty samples conditions must lead to a great accuracy during controls of raw colostrum by the competent authorities. The examined farms need some interventions, aimed at optimizing all aspects of management, in view of the improvement of product that is used both for calves feeding and human destination.