Microbiological quality assessment of fresh tilapia marketed in the Federal District and of the ice used for its conservation

Tilapia (Oreochromis niloticus) is the most cultivated and consumed freshwater fish in Brazil. The present study aimed to evaluate the microbiological quality of ice and fresh tilapia samples commercialized in the Federal District. Tilapia samples were tested for counts of mesophilic and psychrotrophic bacteria, determination of total and thermotolerant coliforms, Staphylococcus aureus counts and presence of Salmonella. Ice samples were analyzed for determination of total coliforms and thermotolerant coliforms and presence of Escherichia coli. Of the 20 samples of fresh tilapia analyzed, ten samples (50%) presented Salmonella (genetically confirmed through the presence of the invA gene) and, therefore, were unfit for consumption. S. aureus was found in 11 samples (55%), and one sample of fillet presented S. aureus counts (3.15 CFU/g) above the limit allowed by Brazilian legislation (3 log CFU/g). S. aureus colonies were confirmed by detection of CoA gene in molecular analysis. Of the 14 ice samples analyzed, 12 samples (85.7%) were unfit for use in fish conservation due to the presence of total coliforms and 9 ice samples (64.3%) were also contaminated with thermotolerant coliforms. E. coli was isolated from 6 ice samples (42.9%) and confirmed in the molecular analysis through the amplification of the MalB gene. In conclusion, the high contamination of tilapia samples with Salmonella and of the ice used for its conservation with coliforms and E. coli indicates the need for better hygienic practices in the tilapia production chain, to increase its quality and microbiological safety.

Supplementation of oligosaccharide-based polymer enhanced growth and disease resistance of weaned pigs by modulating intestinal integrity and systemic immunity

Background There is a great demand for antibiotic alternatives to maintain animal health and productivity. The objective of this experiment was to determine the efficacy of dietary supplementation of a blood group A6 type 1 antigen oligosaccharides-based polymer (Coligo) on growth performance, diarrhea severity, intestinal health, and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli (ETEC), when compared with antibiotics. Results Pigs in antibiotic carbadox or Coligo treatment groups had greater (P < 0.05) body weight on d 5 or d 11 post-inoculation (PI) than pigs in the control group, respectively. Supplementation of antibiotics or Coligo enhanced (P < 0.05) feed efficiency from d 0 to 5 PI and reduced (P < 0.05) frequency of diarrhea throughout the experiment, compared with pigs in the control group. Supplementation of antibiotics reduced (P < 0.05) fecal β-hemolytic coliforms on d 2, 5, and 8 PI. Pigs in antibiotics or Coligo groups had reduced (P < 0.05) neutrophil counts and serum haptoglobin concentration compared to pigs in the control group on d 2 and 5 PI. Pigs in Coligo had reduced (P < 0.05) total coliforms in mesenteric lymph nodes on d 5 and 11 PI, whereas pigs in antibiotics or Coligo groups had reduced (P < 0.05) total coliforms in spleen on d 11 PI compared with pigs in the control group. On d 5 PI, pigs in the Coligo group had greater (P < 0.05) gene expression of ZO1 in jejunal mucosa, but less (P < 0.05) mRNA expression of IL1B, IL6, and TNF in ileal mucosa, in comparison with pigs in the control group. Supplementation of antibiotics enhanced (P < 0.05) the gene expression of OCLN in jejunal mucosa but decreased (P < 0.05) IL1B and IL6 gene expression in ileal mucosa, compared with the control. On d 11 PI, supplementation of antibiotics or Coligo up-regulated (P < 0.05) gene expression of CLDN1 in jejunal mucosa, but Coligo reduced (P < 0.05) IL6 gene expression in ileal mucosa compared to pigs in the control group. Conclusions Supplementation of Coligo improved growth performance, alleviated diarrhea severity, and enhanced gut health in weaned pigs infected with ETEC F18 in a manner similar to in-feed antibiotics.

Seasonal variation in the physicochemical and bacteriological qualities of well water in two sub-divisions of Moundou city (Southern Chad, Central Africa)

This study were carried out from May 2019 to July 2020 with the aimed of evaluating the physicochemical and bacteriological quality of well water in the City of Moundou (Chad). The physicochemical analysis showed that, the water from wells in the two sub-divisions were of very poor quality with an average concentration in Suspended Solids (SS) 30.73 ± 2 1.72 mg.L-1, a Turbidity of 11.10 ± 13.34 FTU, the Electrical Conductivity of 1625.9 ± 1398.6, a Total hardness of 1693.1 ± 1198.2 mg.L-1, Biochemical Oxygen Demand (BOD5) of 167.67 ± 60, 28 mg.L-1, the Chemical Oxygen Demand (COD) 605.93 ± 259.98 mg.L-1 and organic matter 3.75 ± 2.40 mg.L-1. The contamination rate (% non-compliance) of the water points indicates that, during the rainy season the wells were moderately contaminated. Salmonella spp and Escherichia coli induced 29% and 14% respectively, of samples which did not comply with the WHO evaluation criteria (0 germ/mL). As for Total Coliforms and Fecal Coliforms, they were 93% non-compliant each time in the well water samples analyzed. During the dry season, the wells were heavily contaminated with Salmonella spp, Escherichia coli, Total Coliforms and Fecal Coliforms induced approximately 100% of samples were not conform to the criteria of the WHO (0 germ/mL). These waters are therefore not safe for direct consumption without treatment.

Evaluation of an alternative household water treatment system based on slow filtration and solar disinfection

Drinking water consumption is essential to maintain a good quality of life, but it is not available for all communities. Therefore, this work aimed to develop an alternative and accessible process for water treatment, based on filtration and solar disinfection, and evaluate it in both bench and pilot scales. The construction cost of the system was estimated and compared with other available options so that its economic viability could be discussed. For this purpose, water from a stream was collected and analyzed. A filter made of PVC tubes, sand, and gravel was built, acting, respectively, as a column, filtering medium, and support layer. As for the disinfection process, the SODIS (Solar Water Disinfection) methodology was adopted. The water was exposed to the sun, and the best exposure time was determined based on the analysis of total coliforms and E. coli. Finally, a prototype was built for a flow rate of 37.5 L d−1, consisting of two filters operating at a filtration rate of 2.38 m3 m−2 d−1. About 97% turbidity removal was obtained, as well as 99.9% for total coliforms and 99.1% for E. coli. It is estimated that the cost of building a water treatment system for one person is approximately USD 29.00.

Modification of microbiological quality and valorization of different ruminants species ruminal content in farm animals feeding

This study is based on the microbiological analysis of a common slaughterhouse by-product which is the rumen content, before and after treatment with HCl 1N, targeting its valorization in domestic animal feeding. A total of 24 rumen content samples were collected in pairs (two series) immediately after slaughter from 12 ruminants (cattle, sheep and goats). The first series was not treated with HCl (N0 = 12), while the second series was treated with HCl 1N (N1 = 12) to adjust its pH to about 2. Then all samples (series 1 and 2) were subject to a group of microbiological analyzes targeting identification and enumeration of total aerobic mesophilic flora; fecal and total coliforms; Clostridium perfringens; Staphylococcus aureus; Salmonella spp. as well as yeasts and molds. The results revealed that after lowering the pH to about 2, the 2nd series samples were considered of satisfactory quality, with reference to Algerian microbiological standards for livestock feeds. The reduction rates of germs in the 2nd series compared to the 1st series were as follows: total aerobic mesophilic flora (86.45%), total coliforms (96.43%), faecal coliforms (70.41). %), Clostridium perfringens (88.4%), yeast and mold (87.75%). The total absence of Staphylococcus aureus and Salmonella spp. was registered.

Using Peroxymonosulfate-Ozone Advanced Oxidation For The Treated Wastewater Disinfection and Amoxicillin Micro-Pollutant Removal Simultaneously

Due to the recent efforts to improve the conventional disinfection methods efficiency of wastewater treatment plants effluent, in this study, the efficiency of the peroxymonosulfate-ozone (PMS+O3) advanced oxidation process in lab scale by the aim of disinfection and simultaneous removal of existing amoxicillin micro-pollutant under optimum operational condition was investigated for the first time. Furthermore, the results were compared with those obtained from the experiments conducted employing persulfate-ozone (PS+O3), hydrogen peroxide-ozone (H2O2+O3), and ozonation (O3) processes. For this purpose, the main parameters including the total coliforms, amoxicillin concentration, turbidity, chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total nitrogen (TN), electrical conductivity (EC), total dissolved solids (TDS), and total suspended solids (TSS) were considered. The test results show that under optimized operational conditions (retention time of 20 minutes, ozone dosage rate of 0.83 mmol/L, and peroxymonosulfate concentration of 0.06 mmol , 99.99% total coliforms (e.g., the number of total coliforms reached consistently less than 400 MPN in 100 ml) removal was reached by peroxymonosulfate-ozone advanced oxidation process. Also, amoxicillin concentration removal efficiency reached 90±2%. In comparison, although the total coliforms reduction of PS+O3 and H2O2+O3 methods in 30 min are approximately the same, the amoxicillin concentration removal efficiency is about 60-70%. Due to the importance of ensuring effluent quality, the related removal efficiency of other considered parameters is also evaluated and presented. Eventually, the peroxymonosulfate-ozone method can be considered as a novel efficient approach for wastewater plants effluent disinfection and amoxicillin micro-pollutant removal simultaneously which is a novel approach.

Microbiological and physico-chemical characterisation of well water in the town of Korhogo, Côte d’Ivoire

Water is essential to the life of every living organism. The water used by the consumer must be safe for the preservation of his health. The objective of this study was to assess the quality of well water used in households in the city of Korhogo. To do this, water samples were taken from the wells of different households. Parameters such as pH, temperature, electrical conductivity and total dissolved solids were measured at the sampling sites. Nitrates and ammonium were determined by spectrophotometric methods using sodium salicylate and indophenol blue, respectively. The membrane filtration technique has been used for the enumeration of total coliforms, Escherichia coli, fecal enterococci, sulfite-reducing anaerobic bacteria, yeasts and moulds. The agar incorporation method was used for the enumeration of mesophilic aerobic germs. The non-conformity relative to pH was 73%. All wells were contaminated with nitrates and ammonium. Non-compliance rates of 80% and 53% were obtained for nitrates and ammonium respectively. Non-compliance with mesophilic aerobic germs, total coliforms, E. coli and fecal enterococci was 100% for each indicator. No spore of sulphite-reducing clostridia has been identified. Contamination rates of 80% (mould) and 67% (yeast) were recorded. The moulds isolated from the various water samples belong to the genus Aspergillus. The quality of well water in households is not suitable for human consumption. These waters require treatment or household residents must switch to other safe sources of drinking water.

Microbiological Quality of Tomatoes (Solanum lycopersicum L.) Sold in the Markets of Korhogo (Côte d’Ivoire)

Aims: The present work is part of a sanitary quality control of market garden products in Korhogo. The objective of this study was to know the microbiological quality of tomatoes (Solanum lycopersicum L.) sold on the markets of the city of Korhogo. Place and Duration of Study: The analyses were carried out at the microbiology laboratory of Peleforo Gon Coulibaly University during the months of October, November and December 2020. Methodology: Germs such as molds, yeasts, mesophilic aerobic germs, total coliforms, Staphylococcus aureus, Escherichia coli and Clostridium were tested and enumerated on 40 tomato samples from the markets of Haoussabougou, Koko, Sinistré and the big market according to conventional microbiology methods. Results: The average loads of molds and yeasts range from 1.2x104 to 6x105 CFU/g. The average loads of mesophilic aerobic germs vary from 2.3x104 to 2.3x105 CFU/g. The highest loads recorded for Staphylococcus aureus and total coliforms were 3.1x104 CFU/g and 1.5x104 CFU/g respectively. Escherichia coli (4x101 CFU/g) was isolated only from tomatoes collected in Haoussabougou. As for the Clostridium genus, it was not detected on all the tomatoes analyzed. Conclusion: In general, the microbial loads of the analyzed samples are higher than the accepted norm. Thus, the tomatoes sold on the markets of the city of Korhogo have an unsatisfactory microbiological quality. It is advisable to clean, disinfect and rinse these tomatoes carefully with drinking water before consuming them raw.

Identification of Algae as Water Quality Bioindicators in the Water Intakes of Two Municipalities of the Department of Quindío

En los ecosistemas acuáticos, la contaminación provoca una serie de modificaciones fisicoquímicas, repercuten en la composición y distribución de las comunidades presentes, las principales perturbaciones causadas en estos ecosistemas están relacionadas con la contaminación de origen doméstico, industrial, agrícola, minero y deforestación. Las algas son organismos que responden a impactos antropogénicos, convirtiéndose en buenos indicadores de calidad del agua, estos organismos, cuando se encuentran invariablemente en un ecosistema indican alguna condición medioambiental más o menos definida. El objeto de este estudio fue identificar los géneros de algas microscópicas indicadores de calidad del agua, presentes en las bocatomas de dos municipios del departamento del Quindío. El estudio se realizó en el departamento del Quindío, Colombia; en las bocatomas de los municipios de Salento y Montenegro, se realizaron dos salidas de campo en los meses de marzo y mayo para recolectar muestras de agua y medir las variables fisicoquímicas; Se realizó un análisis de comparación canónica entre la abundancia de algas y protozoos con respecto a las variables fisicoquímicas presentes, para esto se halló el índice de Shannon para los géneros de algas y protozoos encontrados en cada bocatoma. Se identificaron 20 géneros de Algas, 4 Protozoos y 3 Helmintos; se halló la presencia de coliformes totales para ambas bocatomas. Los géneros más abundantes de algas fueron Navicula y Oscilatoria los cuales se presentaron en todos los muestreos; los géneros de protozoos que mayor abundancia presentaron fueron Stylonychia y Colpidium y el género de Helmintos que se encontró para ambos muestreos fue Taenia. composition and distribution of the communities present, The main disturbances in these ecosystems are related to pollution from domestic, industrial, agricultural, mining and deforestation sources. Algae are organisms that respond to anthropogenic impacts, becoming good indicators of water quality, these organisms, when found invariably in an ecosystem indicate some more or less defined environmental condition. The aim of this study was to identify the microscopic algal genera, indicators of water quality, present in the mouths of two municipalities in the department of Quindío. The study was conducted in the department of Quindío, Colombia; in the mouths of the municipalities of Salento and Montenegro, two field trips were made in the months of March and May to collect water samples and measure physicochemical variables; A canonical comparison analysis was made between the abundance of algae and protozoa with respect to the physico-chemical variables present, for this the Shannon index was found for the genera of algae and protozoa found in each mouthpiece. We identified 20 genera of Algae, 4 Protozoa and 3 Helminths; we found the presence of total coliforms for both mouthfuls. The most abundant genera of algae were Navicula and Oscillator, which occurred in all the samples; The most abundant protozoa genera were Stylonychia and Colpidium, and the genus of Helminths found for both samples was Taenia.

Nopalea cochenillifera Biomass as Bioadsorbent in Water Purification

Contaminated water consumption is one of the greatest risks to human health, especially in underdeveloped and developing countries. Water is a universal right, but millions of people worldwide consume untreated surface water. The objective in this study is to evaluate water purification with Nopalea cochenillifera var. Miúda biomass. Fragments (1, 2, and 3 g) of N. cochenillifera were added to the aqueous solution containing red-yellow Chromic and Podzolic Luvisol simulating turbid water sources in Northeastern Brazil. The total, non-structural (i.e., reducing and non-reducing sugars, alcohol insoluble solids), and structural (i.e., pectin) carbohydrates, adsorption kinetics, turbidity, electrical conductivity, pH, zeta potential, and total coliforms presence were evaluated. Findings show that the Nopalea cochenillifera biomass adsorbed the suspended particles in the aqueous solution, making it more translucent due to the complex and heterogeneous adsorbents’ ion exchange matrix, but the biomass addition did not eliminate total coliforms from the aqueous solution. We concluded that the Nopalea cochenillifera biomass water treatment reduces suspended dissolved particles and turbidity, but it needs to be associated with other treatments to eliminate total coliforms and ensure water safety for human consumption.