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.

POTENCIAL DE REÚSO DE EFLUENTES TRATADOS PARA IRRIGAÇÃO PERIURBANA NO MUNICÍPIO DE GUARABIRA/PB

POTENCIAL DE REÚSO DE EFLUENTES TRATADOS PARA IRRIGAÇÃO PERIURBANA NO MUNICÍPIO DE GUARABIRA/PB LIBIANE MARINHO BERNARDINO1; PATRÍCIA DA SILVA COSTA2; VERA LÚCIA ANTUNES DE LIMA3 E RENER LUCIANO DE SOUZA FERRAZ4. 1 Mestranda em Gestão e Regulação em Recursos Hídricos, Unidade Acadêmica de Tecnologia do Desenvolvimento, UFCG, Rua Luiz Grande, s/n, Frei Damião, CEP 58540-000, Sumé, PB, Brasil, [email protected] 2 Doutoranda em Engenharia Agrícola, Unidade Acadêmica de Engenharia Agrícola, UFCG, Rua Aprigio Veloso, 882, Universitário, CEP 58429-900, Campina Grande, PB, Brasil, [email protected] 3 Profa. Doutora em Engenharia Agrícola, Unidade Acadêmica de Engenharia Agrícola, UFCG, Rua Aprigio Veloso, 882, Universitário, CEP 58429-900, Campina Grande, PB, Brasil, [email protected] 4 Prof. Doutor em Engenharia Agrícola, Unidade Acadêmica de Desenvolvimento Sustentável do Semiárido, UFCG, Rua Luiz Grande, s/n, Frei Damião, CEP 58540-000, Sumé, PB, Brasil, [email protected] 1 RESUMO A água é um recurso finito que se encontra escasso, o que justifica a busca por gestão e inovação de práticas que a preserve. O objetivo da pesquisa é avaliar o potencial de reúso dos efluentes tratados para irrigação periurbana. Foram levantados dados de uma Estação de Tratamento de Esgotos (ETE), localizada no município de Guarabira, PB, e operada pela Companhia de Água e Esgotos do Estado da Paraíba (CAGEPA), durante o período de janeiro a dezembro de 2019. Analisou-se os seguintes parâmetros físico-químicos e bacteriológicos: Potencial Hidrogeniônico (pH), Condutividade Elétrica (CE), Demanda Bioquímica de Oxigênio (DBO), Demanda Química de Oxigênio (DQO), Sólidos Totais (ST), Oxigênio Dissolvido (OD), Fósforo Total, e Coliformes Termotolerantes. Os dados foram submetidos à análise descritiva e expresso em valores mínimos, máximos e médios. Os indicadores foram satisfatórios para irrigação restrita, porém com a necessidade de tratamento complementar para determinados cultivos. O potencial de reúso dos efluentes tratados na ETE pode beneficiar uma área de 118,7 ha considerando uma demanda de irrigação de 18.000 m³ ha-1 ano-1, o que demonstra ser um recurso sustentável e que precisa ser regulamentado no Brasil. Palavras-chave: recursos hídricos, resíduos líquidos, tratamento de água, fertirrigação. BERNARDINO, L. M.; COSTA, P. S.; LIMA, V. L. A.; FERRAZ, L. R. S. REUSE POTENTIAL OF TREATED EFFLUENTS FOR PERIURBAN IRRIGATION IN THE MUNICIPALITY OF GUARABIRA/PB 2 ABSTRACT Water is at the center of sustainable development and a finite resource that is in short supply, which justifies the search for management and innovation of practices that preserve it. This research aims to evaluate the potential for reuse of treated effluent for periurban irrigation. Data were collected from a Sewage Treatment Plant (STP), located in the municipality of Guarabira, PB, and operated by the Water and Sewage Company of the State of Paraíba (CAGEPA), during the period from January to December 2019, with the analysis of the following physicochemical and bacteriological parameters: Hipogenic Potential (pH), Electrical Conductivity (CE), Biochemical Oxygen Demand (DBO), Chemical Oxygen Demand (DQO), Total Solids (ST), Dissolved Oxygen (OD), Total Phosphorus, and Thermotolerant Coliforms. The data were submitted to the descriptive analysis and expressed as minimum, maximum and average values. The indicators were satisfactory for restricted irrigation, but with the need for complementary treatment for certain crops. The potential for reuse of the effluents treated in the ETE can benefit an area of 118.7 ha considering an irrigation demand of 18,000 m³ ha-1 year-1, which demonstrates to be a sustainable resource that needs to be regulated in Brazil. Keywords: Water resources, liquid waste, water treatment, fertigation.

Effect of turbidity on ultraviolet disinfection of domestic wastewater for agricultural reuse

Water treatment and reuse are fundamental because of the increasing demand for freshwater, especially in agriculture. Accordingly, this study evaluated the effects of turbidity of wastewater processed at the Effluent Treatment Station (ETE) of the UFSCar/Araras and of UV dose on microbial inactivation. The ETE treats up to 2000 L of wastewater daily from toilets and a university restaurant and has five components (grease box, septic tank, microalgae tank, upflow anaerobic filter, and wetlands). Pretreated effluents were used in the experiments, and sampling sites consisted of inspection boxes located after the wetlands. Sample collection, inspection, preservation, and analyses were performed according to standard methods. Sample turbidity was adjusted to 5, 50, 100, 200, and 300 nephelometric turbidity units (NTU), and UV doses of 7.2–28.8 mWs cm-2 were used. A 5 x 5 factorial design (five turbidity levels and five radiation doses) was used, totaling 25 treatments. Each treatment was performed in triplicate. The data were submitted to analysis of variance and Tukey’s test. The results showed that the increase in turbidity significantly decreased disinfection efficiency in samples with turbidity levels higher than 50 NTU. The microbial inactivation coefficients obtained here can be extrapolated to disinfection of wastewater with turbidity up to 300 NTU to eliminate thermotolerant coliforms. The UV sterilizer is feasible for wastewater treatment and its reuse in agriculture. Keywords: domestic effluent, sustainability, ultraviolet radiation, water reuse.

Development of Active Packaging Based on Agar-Agar Incorporated with Bacteriocin of Lactobacillus sakei

In the search for new biodegradable materials and greater microbiological safety and stability of perishable food products, this study aimed to develop a bioplastic antibacterial film incorporating bacteriocin for application in commercial curd cheese and monitoring of microbiological stability. Films with good handling characteristics as well as physical, barrier, and mechanical properties were obtained. Regarding the antibacterial activity, the microbial reduction was demonstrated in a food matrix, obtaining a reduction of 3 logarithmic cycles for the group of coagulase positive staphylococci and from 1100 to <3.00 MPN/g in the analysis of thermotolerant coliforms. Therefore, the film presented food barrier characteristics with the external environment and adequate migration of the antibacterial compound to the product, contributing to the reduction of contamination of a food with high initial microbial load.

Post-Treatment of Kennel Wastewater With Different Aeration Strategies

The objective of this study was to evaluate the effect of the introduction of a complementary aerobic treatment composed of a submerged aerated biological filter (SABF) with a secondary clarifier (SC), followed by horizontal subsurface flow constructed wetlands (CWs), after anaerobic units, on the ability to remove pollutants in different aeration phases (Ph1, Ph2, and Ph3) at the effluent treatment station of the Parque Francisco de Assis (PFA) dog shelter. Ph1 and Ph2 had 7 and 5 hours of daily aeration, respectively, and Ph3 had intermittent aeration every 2 hours. The phases were monitored regarding the removal efficiency of organic matter, solids, nutrients (N, P), coliforms, and detection of Giardia and Cryptosporidium. It was found that post-treatment provided greater removal efficiencies and that the aeration strategy of Ph3 showed mean efficiencies of 71% for COD removal and 77% for BOD removal, being similar or statistically higher, even with less biodegradable effluent, than those of Ph1 and Ph2. The SABF and SC removed N by nitrification and denitrification, leaving a total Kjeldahl nitrogen (TKN) concentration in the effluent of 18 mg L−1. The CW showed potential for simultaneous nitrification and denitrification (SND), in addition to solid filtration. The system did not satisfactorily remove thermotolerant coliforms (ThermC) (1 ± 0 log). PCR suggested the presence of the pathogens Giardia and Cryptosporidium in all post-treatment units in Ph1 and Ph2.

Analysis of the Physicochemical and Microbiological Quality of Unfermented Palm Sap Reserved for Infant Feeding

Aim: The study was conducted to evaluate the physicochemical and microbiological parameters that could contribute to the depreciation of the quality of unfermented palm sap used for infant feeding. Study Design: A survey was conducted in 20 villages and camps to determine if the practice was still current. Also, unfermented sap was produced from 5 palms by resource persons to control the quality during the days of exploitation. Place and Duration of Study: The survey was carried out from March 1st to 30th in villages and camps in Central and Central-Western Cote d'Ivoire. The production of the sap took place during one week in the village of Akpessekro. Methodology: 30 people, without distinction randomly crossed were questioned on the food consumed at the age of 0 to 6 months. Also, in the unfermented sap produced acidity, sugar content, loads of GAM, thermotolerant coliforms, enterococci, yeasts and molds were determined and multiple correlations were established between all parameters. Results: In the villages and camps, palm sap is less and less used as infant food. During the first two days of palm farming, the acidity (6 < pH < 6.11) approximates that of breast milk or milk substitutes. However, after these two days, the acidity becomes high and the sugar content too low for infant feeding. In the unfermented sap, the loads of coliform fecal contamination germs are higher than the required standards. Also, the large load of lactic acid bacteria (≥1.5E+04 ufc/ml) and yeasts (1.4E+04 ufc/ml) present in the sap contribute to a depreciation of its quality over the days and when the sap is left to rest. Conclusion: The quality of unfermented palm sap as infant food is not guaranteed. This is one of the reasons why this practice is in decline nowadays.

Evaluation of sanitary quality of goat milk in dairy industries from the Cariri region, state of Paraíba

The sanitary evaluation of equipment and hands is fundamental to investigate the presence of pathogens in the dairy industry. Then, this study aims to evaluate the sanitization of equipment, workers’ hands, raw and pasteurized milk in goat milk dairies in the Cariri region, state of Paraíba. Collected 32 samples of four dairies represented by letters A, B, C, and D. The followings contents were analyzed: mesophiles, total and thermotolerant coliforms, Escherichia coli, Staphylococcus aureus, Samonella spp. and Listeria monocytogenes in the reception tank, pasteurization tank, packing machine, package, wall, workers’ hand, and each dairy’s raw and pasteurized milk. After isolation, 84 colonies were confirmed by MALDI TOF. The indicator microorganisms presented variations for the workers’ hands, while A and B stayed within the patterns. For the equipment, only dairy B was within limits. They were out of the standard for mesophiles, total coliforms, and thermotolerant regarding raw and pasteurized milk. The microorganisms, the Enterobacteriaceae family presented a higher frequency, with 77.38%, and within this family, Escherichia coli, Klebsiella spp., and Enterobacter spp. were the most prevalent. Gram-positive corresponded to 22.62%, Bacillus spp., Staphylococcus spp., Enterococcus spp., and Macrococcus caseolyticus. Listeria monocytogenes and Salmonella spp. were not isolated. These demonstrate failures in goat milk processing with pathogenic bacteria in several dairy plants, indicating the need to adjust the product’s quality control.

Hygienic-sanitary quality of ready-to-eat salmon sashimi (Salmo Salar)

Fifty sashimi samples from 5 restaurants were characterized for enumeration of Aerobic Psychrotrophic Heterotrophic Bacteria (APHB) and Aerobic Mesophilic Heterotrophic Bacteria (AMHB), Enterobacteriaceae, coliforms at 45ºC (thermotolerant coliforms), coagulase-positive Staphylococci, presence of Vibrio parahaemolyticus and Salmonella sp., and determination of hydrogen potential (pH) and total volatile basic nitrogen (TVB-N). The bacterial isolates were evaluated for their resistance profile to the antimicrobial agents Penicillin, Ampicillin, Cefoxitin, Cefotaxime, Amikacin, Gentamicin, Tetracycline, and Trimethropim-sulfamethoxazole. The results showed that APHB, AMHB and coagulase-positive Staphylococci counts and the determination of pH and TVB-N were in accordance with national and international standards adopted as safe limits for consumption. In contrast, the Enterobacteriaceae and thermotolerant coliforms counts and presence of Salmonella sp. and V. parahaemolyticus were in disagreement with those standards, raising concern about the hygienic-sanitary quality of sashimi. The Staphylococcus aureus and V. parahaemolyticus isolates showed resistance to Penicillin, Ampicillin, Cefoxitin, Cefotaxime, Tetracycline, Gentamicin, and Amikacin, while the Salmonella sp. isolate showed no resistance to all the antimicrobial agents studied. The results showed that 48% of the samples were fit for consumption while 52% had unsatisfactory hygienic-sanitary quality for the parameters evaluated.

Microbiological quality assessment of five common foods sold at different points of sale in Burkina-Faso

The aim of the present study was to assess the microbial quality of five different types of food such as bread, pasta, rice with sauce, beans and milk sold in five localities of Burkina Faso. One hundred and one (101) samples were collected and microbial quality were assessed by evaluating the food hygiene indicators such as total aerobic mesophilic flora, total coliforms, thermotolerant coliforms, yeast and mould. Food safety indicators such as Escherichia coli , Salmonella , coagulase-positive staphylococci, Clostridium perfringens and Bacillus cereus were checked too. All samples were analyzed under ISO methods.

Bacteriological assessment of water from an Eastern Amazon river: challenges in ensuring basic sanitary coverage in riverside communities

This study aimed to analyze the water quality of a river in the Eastern Amazon and relate the results obtained with the lack of basic sanitation in the region. Two samples were collected from strategic points of the river and were submitted to the collimetry technique with multiple tubes to calculate the most probable number (MPN) of thermotolerant coliforms present in the water. The samples were then seeded on CLED and Hektoen agar and analyzed in a mass spectrophotometer for final identification of microorganisms. A high number of thermotolerant coliforms was detected, in addition to bacteria of clinical importance, such as Pseudomonas aeruginosa, Shigella spp. and Cronobacter sakazakii. The lack of basic sanitation in the community surrounding the river is the main cause for the significant number of thermotolerant coliforms, demonstrated by the discrepancy in the MPN between samples 1 and 2. The difficulties in guaranteeing basic sanitation in the Amazon are highlighted and the need to implement public policies and carry out health surveillance studies in these populations is reinforced.