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BACKGROUND Brazil is responsible for 60% of the global production of orange juice, accounting for over three‐quarters of global orange juice exports, resulting in large quantities of orange bagasse (OB). This is an underutilized byproduct of the orange juice industry and corresponds to 50% of the fruit weight. The objectives of this study were to produce cellulose from OB using a combination of ultrasound and peracetic acid (PA) treatment, and to characterize the obtained materials according to their microstructure, crystallinity, thermal stability and water sorption behavior, and their cellulose, hemicellulose and lignin contents. RESULTS: Ultrasound pretreatment alone was not effective in altering the composition of OB. Samples subjected to both ultrasound and PA presented higher cellulose contents and lower hemicellulose and lignin contents in comparison to their respective samples undergoing PA treatment alone. The sample subjected to ultrasound for 10 min at a 30% amplitude combined with PA treatment for 24 h (USPA.24) resulted in the highest crystallinity index (54%), with 81.49% cellulose, 0.88% hemicellulose and 2.68% lignin. The increase in cellulose content of samples also resulted in lower water‐holding capacity, solubility and water adsorption capacity of samples. CONCLUSION: Ultrasonication associated with PA treatment can be considered a promising approach and effective protocol for the extraction of cellulose from lignocellulosic residues, and it has the advantages of simplicity and environmental friendliness when compared to conventional methods, reducing the toxicity and amount of the resulting effluents. © 2020 Society of Chemical Industry (SCI) [ABSTRACT FROM AUTHOR]

• Chlorine and peracetic acid were inefficient in reducing the organic matter. • Simultaneous action on bacteria and sulfide was observed. • Peracetic acid showed a better performance than chlorine for sulfide oxidation. • Optimal condition was efficiently applied to continuous mode flow. Decentralized wastewater treatment is a viable and sustainable alternative to having universal access to sanitation, especially for developing countries and small communities. Chlorine and peracetic acid (PAA) have been studied widely to promote wastewater disinfection, however there are few comparative studies applied to decentralized wastewater treatments. This paper investigated the application of chlorine and PAA in two biological reactor effluents regarding disinfection, organic matter oxidation, and odor control. Full factorial design was used to quantify the effect of the Chlorine and PAA dose (5, 10, and 15 mg L−1) and contact time (5, 10, and 15 min) in the batch experiments. Chlorine and PAA were inefficient in reducing the organic matter showing an increment in the chemical oxygen demand (COD) concentration in most of the tests. Sulfide was oxidized by chlorine (0.0–39.9 %) and PAA (3.5–73.5 %) for both reactor effluents. Inactivation results from E. coli and total coliform by chlorine and PAA showed that the effluent quality has a stronger influence than the disinfectant type. The best operational condition (15 mg L−1, 15 min) were also tested in the continuous mode flow, whose results are in agreement with those found in the batch tests. These results provide valuable support in terms of establishing practical guidelines for chlorine and PAA applications in decentralized wastewater treatment in Brazil. [ABSTRACT FROM AUTHOR]

This work evaluates the performance of peracetic acid (PAA) for the disinfection of stormwater runoffs contaminated by domestic sewage with the objective of using the collecting systems as contact reactors for in-situ disinfection. PAA is increasingly being used as a substitute for chlorination in the disinfection of wastewaters because of its rapid degradability and the absence of chlorinated organic by-products. In Brazil, and despite the adoption of the separator system in sewage systems, there is a large amount of domestic effluents that are piped directly into the stormwater systems, contributing to the contamination of water bodies. The efficiency of the disinfection of Escherichia Coli was evaluated by applying different doses (2, 5 and 10 mg.L-1) of PAA with short contact times (2, 5 and 10 minutes) in real stormwater samples collected at three different points of the stormwater system of the city of Rio de Janeiro. Trials were performed simulating the conditions and flow times available in the stormwater sewers. The results were excellent, with removals up to 5 log units with 10 mg.L-1 peracetic acid and 2 minutes contact time. Where there was available a contact time of at least 5 minutes, a dose of 5 mg.L-1 was sufficient. [ABSTRACT FROM AUTHOR]

A trial was conducted to determine the genotypic and phenotypic profiles of Listeria monocytogenes (LM) isolated from chicken meat and chicken-meat processing environment in an export-authorized industrial facility in Brazil. A total of 37 LM isolates were separated according to their genetic similarity by pulsed-field gel electrophoresis (PFGE), classified by serotype and lineage using multiplex PCR, tested for antibiotic resistance using the disk-diffusion technique, and analyzed for disinfectant susceptibility using the minimal inhibitory concentration (MIC) approach. The majority of the isolates belonged to lineage II, serotypes 1/2a or 3a. Genotypically, isolates from packaged frozen carcasses and knives & boards of the cutting room were similar to those of carcasses after chiller. Isolates from packaged frozen boneless thighs, however, were very peculiar. Regardless the origin, high level of resistance to peracetic acid, ampicillin and sulfonamides were detected. Overall, our findings suggest that the prevalence of LM in the cutting room is not sustained by the continuous flow of new bacteria, but mainly by an already established microbiota that persists in the environment. Therefore, more effective strategies of cleaning and disinfection must be adopted by the chicken meat industry in order to reduce the prevalence of LM in the processing environment. • Multi-drug resistant Listeria monocytogenes (LM) was detected in chicken processing. • LM isolates were also resistant to peracetic acid. • LM isolates belonged mostly to lineage II, serotypes 1/2a or 3a. • LM from packaged carcasses was genotypically similar to that isolated after chiller. • LM from packaged thighs was peculiar, probably originated from the cutting environment. [ABSTRACT FROM AUTHOR]

The aims of this study were to analyze the biofilm-producing ability of 98 strains isolated from different surface materials in poultry cutting rooms; to assess the presence of the most important to Salmonella biofilm formation genes adrA and csgD in these strains; and to evaluate the tolerance biofilms formed in polypropylene and polyurethane slides to sanitizers commonly used in the industry. Viable cells were removed from the slides soon after treatment with sanitizers, and then submitted to reincubation for a new count. Only one strain was a strong biofilm-producer in polystyrene; 70% of strains were weak, and 29% were moderate producers. Both genes were found in all strains. There were differences in adhesion to polypropylene and polyurethane, and scanning electron microscopy showed that polyurethane surface was more irregular. No viable cells were recovered in polypropylene slides treated with sanitizers; in polyurethane, reduction in viable cell counts soon after sanitizer treatment was enough to consider that sanitizers were efficient. On the other hand, treatment with peracetic acid was not considered efficient. Results of this study should be considered a food safety warning, due to the importance of the biofilm-producing ability both in vitro and in real poultry processing plants. [ABSTRACT FROM AUTHOR]

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After a new regulation on the control of citrus canker (Xanthomonas citri subsp. citri) came into force in Brazil in 2017, the post-harvest sanitization of citrus fruit became mandatory to prevent dissemination of the causal pathogen and enable the commercial trade of citrus to other states and countries. Although several sanitizers are available worldwide for decontamination of fresh produce, only sodium hypochlorite is legally required by the country for decontamination of citrus fruit traded with other states and countries against X. citri in the packing house. Thus, the objectives of this study were to assess the efficiency of chlorine dioxide, peracetic acid, and calcium oxychloride as alternative sanitizers and exposure times of 1 and 2 min for the post-harvest decontamination of citrus fruit against X. citri. Sodium hypochlorite, the legally required standard, was used as control. The sanitizers were evaluated regarding the capacity to eliminate live X. citri in solution immediately or 1 h after exposure to the products and the efficiency in disinfesting artificially and naturally contaminated lime fruit. An additional assessment was carried out to determine the infective potential of X. citri suspensions at different concentrations in order to evaluate the risk of disease dissemination by the remaining bacterial population on the fruit following treatment. All the assessed sanitizers were able to completely eliminate X. citri in suspension immediately after treatment. In artificially and naturally contaminated fruit, the sanitizers promoted a significant reduction of 2.4–2.8 and 1.1 to 1.5 log 10 cfu/mL, respectively, in the population of live bacteria when compared to the untreated control. In these experiments, the amount of X. citri that remained on the fruit ranged from 0.5 to 1.0 and 0.1 to 0.3 log 10 cfu/mL, respectively, regardless of the exposure time. The labeled concentrations and treatment periods assessed effectively decontaminated fruit with X. citri and demonstrated little or no risk of pathogen spread from treated fruit. • Chlorine dioxide is an efficient citrus fruit sanitizer against Xanthomonas citri. • Peroxyacetic acid is an efficient citrus fruit sanitizer against Xanthomonas citri. • Chlorine dioxide is an efficient citrus fruit sanitizer against Xanthomonas citri. • Immersion of citrus fruit in sanitizer for 1 or 2 min is equally efficient. [ABSTRACT FROM AUTHOR]

Background and Aims: Attention to patient safety has increased recently due to outbreaks of nosocomial infections associated with GI endoscopy. The aim of this study was to evaluate current cleaning and disinfection procedures of endoscope channels with high bioburden and biofilm analysis, including the use of resistant mycobacteria associated with postsurgical infections in Brazil., Methods: Twenty-seven original endoscope channels were contaminated with organic soil containing 10(8) colony-forming units/mL of Pseudomonas aeruginosa, Staphylococcus aureus, or Mycobacterium abscessus subsp bolletii. Biofilms with the same microorganisms were developed on the inner surface of channels with the initial inoculum of 10(5) colony-forming units/mL. Channels were reprocessed following current protocol, and samples from cleaning and disinfection steps were analyzed by bioluminescence for adenosine triphosphate, cultures for viable microorganisms, and confocal microscopy., Results: After contamination, adenosine triphosphate levels increased dramatically, and high bacterial growth was observed in all cultures. After cleaning, adenosine triphosphate levels decreased to values comparable to precontamination levels, and bacterial growth was demonstrated in 5 of 27 catheters, 2 with P aeruginosa and 3 with M abscessus. With regard to induced biofilm, a remarkable reduction occurred after cleaning, but significant microbial growth inhibition occurred only after disinfection. Nevertheless, viable microorganisms within the biofilm were still detected by confocal microscopy, more so with glutaraldehyde than with peracetic acid or O-phataladehyde., Conclusion: After the complete disinfection procedure, viable microorganisms could still be detected within the biofilm on endoscope channels. Prevention of biofilm development within endoscope channels should be a priority in disinfection procedures, particularly for ERCP and EUS., (Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Lettuce is a leafy vegetable widely used in industry for minimally processed products, in which the step of sanitization is the crucial moment for ensuring a safe food for consumption. Chlorinated compounds, mainly sodium hypochlorite, are the most used in Brazil, but the formation of trihalomethanes from this sanitizer is a drawback. Then, the search for alternative methods to sodium hypochlorite has been emerging as a matter of great interest. The suitability of chlorine dioxide (60 mg L(-1)/10 min), peracetic acid (100 mg L(-1)/15 min) and ozonated water (1.2 mg L(-1)/1 min) as alternative sanitizers to sodium hypochlorite (150 mg L(-1) free chlorine/15 min) were evaluated. Minimally processed lettuce washed with tap water for 1 min was used as a control. Microbiological analyses were performed in triplicate, before and after sanitization, and at 3, 6, 9 and 12 days of storage at 2 ± 1 °C with the product packaged on LDPE bags of 60 μm. It was evaluated total coliforms, Escherichia coli, Salmonella spp., psicrotrophic and mesophilic bacteria, yeasts and molds. All samples of minimally processed lettuce showed absence of E. coli and Salmonella spp. The treatments of chlorine dioxide, peracetic acid and ozonated water promoted reduction of 2.5, 1.1 and 0.7 log cycle, respectively, on count of microbial load of minimally processed product and can be used as substitutes for sodium hypochlorite. These alternative compounds promoted a shelf-life of six days to minimally processed lettuce, while the shelf-life with sodium hypochlorite was 12 days.