Ozonation for Pseudomonas paracarnis control: biofilm removal and preservation of chicken meat during refrigerated storage.

Ozone has been studied to control microorganisms in food, as well as to control biofilm. In this context, the goals of this work were to determine the effect of ozonated water in the removal of Pseudomonas paracarnis biofilm and the effect of ozone gas and ozonated water on inactivating P. paracarnis in deboned chicken breast meat and its effect on product color. AISI 304 coupons were used as a surface for biofilm formation. The coupons were immerged into minimal medium for Pseudomonas inoculated with the P. paracarnis overnight culture (1% w/v) followed by incubation at 25 °C for 7 days. To obtain ozonized water, two different systems were used: system with microbubble generator (MB) and system with porous stone diffuser (PSD). The inlet ozone concentration was 19 mg/L and flow rate of 1 L/min. The coupons were subjected to ozonized water for 10 and 20 min. The chicken breast meat was exposed to gaseous ozone and ozonized water for 40 min. After the ozonation process, chicken meat samples were stored at 8 °C, for 5 days. More expressive removals of biofilm were obtained when using ozonized water obtained in the system with microbubble generator (MB for 20 min-reduction of 2.3 log cycles) and system with porous stone diffuser (PSD for 10 min-reduction of 2.7 log cycles; PSD for 20 min-reduction of 2.6 log cycles). The treatment of chicken meat with ozone gas resulted in lower counting of Pseudomonas, when compared with the control treatments and with ozonized water, both immediately after ozonation (day 1) and after 5 days of storage. The luminosity in the chicken meat samples treated with ozonized water was higher than that verified in the control treatments and with ozone gas, immediately after ozonation (day 1). A similar trend was observed in hue angle and color difference, in which the highest values were obtained for treatment with ozonized water. Based on the results obtained in this study, it was concluded that ozonated water can be used to remove P. paracarnis biofilm from stainless steel under static conditions and gaseous ozone is more efficient in the inactivation of P. paracarnis from chicken breast meat, when compared to ozonated water.

Efecto antimicrobiano de la irrigación postquirúrgica con agua ozonificada en el alveolo durante exodoncias simples / Antimicrobial effect of postsurgical irrigation with ozonated water in the socket during simple extractions

El presente estudio se propone evaluar los efectos postquirúrgicos de la irrigación del alveolo con agua ozonificada durante una exodoncia simple en pacientes de la Unidad de Atención Odontológica UNIANDES. Para ello se seleccionaron 30 pacientes a los que se les practicaron dos exodoncias en sesiones diferentes aplicándose agua ozonificada post exodoncia solamente en la primera de ellas, lo que permitió comparar en cada alternativa el comportamiento de la intensidad del dolor, grado de inflamación, infección, y tiempo de cicatrización, de manera que las pruebas estadísticas fueron significativas mostrando asociación lineal entre las variables irrigación del alveolo y dolor; y entre la irrigación del alveolo e inflamación. Asimismo, se observó una cicatrización más rápida en los pacientes tratados con el agua ozonificad en comparación a aquellos que no fueron tratados. Además, ese observó una disminución de la biota bucal, especialmente Lactobacillus spp y Streptococcus mutans al irrigar con agua ozonificada responsable de la inflamación y por ende del dolor de los pacientes. Por otra parte, se aprecia un escaso conocimiento acerca de la utilización de agua ozonificada en el alvéolo por parte de los estudiantes, mientras que los profesionales odontólogos, y a pesar de tener conocimiento de los beneficios del agua azonificada, son poco proclives a su uso(AU)

The present study aims to evaluate the post-surgical effects of alveolar irrigation with ozonated water during a simple extraction in patients of the UNIANDES Dental Care Unit. For this, 30 patients were selected who underwent two extractions in different sessions, applying post-extraction ozonated water only in the first one, which allowed comparing in each alternative the behavior of pain intensity, degree of inflammation, infection, and healing time, so that the statistical tests were significant, showing a linear association between the variables irrigation of the socket and pain; and between alveolar blood supply and inflammation. Likewise, faster healing was observed in patients treated with ozonated water compared to those who were not treated. In addition, he observed a decrease in the oral biota, especially Lactobacillus spp and Streptococcus mutans when irrigating with ozonated water, responsible for the inflammation and therefore the pain of the patients. On the other hand, there is little knowledge about the use of ozonated water in the alveolus by students, while dental professionals, despite being aware of the benefits of zonated water, are not inclined to use it(AU)

Inactivation of Escherichia coli O157:H7 by ozone in different substrates.

Ozone has a broad antimicrobial spectrum and each microorganism species has inherent sensitivity to the gas. The objective of this study was to evaluate the effect of ozone gas on Escherichia coli O157:H7 inoculated on an organic substrate, and the efficacy of ozonated water in controlling the pathogen. For the first experiment, E. coli O157:H7 (ATCC® 43890™) was inoculated in milk with different compositions and in water, which was ozonated at concentrations of 35 and 45 mg L-1 for 0, 5, 15, and 25 min. In the second experiment, water was ozonated at 45 mg L-1 for 15 min. E. coli O157:H7 was exposed for 5 min to the ozonated water immediately after ozonation, and after storage for 0.5, 1.0, 1.5, 3.0, and 24 h at 8 °C. The results showed that the composition of the organic substrate interfered with the action of ozone on E. coli O157:H7. In lactose-free homogenized skim milk, reductions of 1.5 log cycles were obtained for ozonation periods of 25 min at the concentrations tested. Ozonated water was effective in inactivating of E. coli O157:H7 in all treatments. The efficiency of ozone on E. coli O157:H7 is influenced by the composition of the organic substrates, reinforcing the need for adequate removal of organic matter before sanitization. Furthermore, refrigerated ozonated water stored for up to 24 h is effective in the control of E. coli O157:H7.

Ozone therapy as an adjuvant for endondontic protocols: microbiological – ex vivo study and citotoxicity analyses

ABSTRACT Objectives This study evaluated the antimicrobial efficacy of ozone therapy in teeth contaminated with Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus using a mono-species biofilm model. Parallel to this, the study aimed to evaluate the cytotoxicity of ozone for human gingival fibroblasts. Material and Methods: One hundred and eighty single-root teeth were contaminated with a mono-species biofilm of Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus. Groups were formed: Group I – control; Group II – standard protocol; Group III – standard protocol + ozone gas at 40 µg/mL; and Group IV – standard protocol + aqueous ozone at 8 µg/mL. In parallel, human gingival fibroblasts were submitted to the MTT test. Cells were plated, then ozone was applied as follows: Group I (control) – broth medium; Group II – aqueous ozone at 2 µg/mL; Group III – aqueous ozone at 5 µg/mL; and Group IV – aqueous ozone at 8 µg/mL. Data were submitted to the Kruskal Wallis test and Bonferroni post hoc analyses to assess microbiology and cytotoxicity, respectively (p<0.05%). Results The results revealed antimicrobial efficacy by Group IV with no CFU count. The cytotoxicity assay showed Groups III and IV to be the most aggressive, providing a decrease in cell viability at hour 0 from 100% to 77.3% and 68.6%, respectively. Such a decrease in cell viability was reverted, and after 72 hours Groups III and IV provided the greatest increase in cell viability, being statistically different from Groups I and II. Conclusion According to the applied methodology and the limitations of this study, it was possible to conclude that ozone therapy improved the decontamination of the root canal ex vivo. Ozone was toxic to the cells on first contact, but cell viability was recovered. Thus, these findings suggest that ozone might be useful to improve root canal results.

Aqueous ozone solutions for pesticide removal from potatoes.

The presence of pesticide residues in potatoes is of concern because of the potential impact to human health due to the high consumption of this vegetable. In this study, aqueous solutions with and without ozone saturation as postharvest wash treatment at pH 4.0, 7.0, and 9.0 were tested to remove chlorothalonil from potatoes. The method used for pesticide analysis has been validated, presenting recovery values of 94-103%, with variations in the repeatability coefficients of ≤10.6%, and a quantification limit of 0.05 mg kg-1 Regardless of pH, treatment with aqueous ozone solutions removed 70-76% of the pesticide present in the potato. In the no-ozone treatments, the percentage average removal of chlorothalonil residues in potatoes was only 36%. Over 24 days of storage, the quality of potatoes washed with aqueous ozone solutions was not significantly different from those washed with pure water.

Avaliação da eficiência de diferentes sanificantes em alface (Lactuca sativa) e de suas influências na vida útil do produto / Evaluating the effectiveness of various sanitizers on lettuce (Lactuca sativa) and their influence on the product's life

Os efeitos inativantes da água ozonizada (03 concentração média, 5,2mg/L), das ondas ultra-sônicas(freqüência, 37 kHz), da associação entre ambos, do cloro orgânico a 100 e 200mg/L e do vinagre a 2% e 6%, foram estudados como alternativas aos desinfetantes rotineiros. As amostras foram avaliadas segundo o Número Mais Provável médio de coliformes a 45°C. Isoladamente, o ozônio e o vinagre a 6% apresentaram o melhor efeito sanificante, apresentando reduções respectivas de 95% e 100% em relação ao grupo controle. A associação entre o ozônio e ultra-som, reduziu em 99,6% a carga microbiana. Na concentração de lOOmg/L, o dicloroisocianurato de sódio não apresentou efeito sanificante, porém a 200mglL, a redução foi de 64%. O ozônio promoveu aumento da conservação, entretanto as ondas ultra-sônicas ou a associação entre os processos acelerou o término da vida útil. O vinagre foi o sanificanteque mais comprometeu a vida útil do produto. A redução encontrada foi de 62,2% para o vinagre a2% e 100% para o vinagre a 6%. (AU)

The inactivate effects of ozonated water (03 medium concentration, 5.2mg/L), of ultrasonic waves (frequency, 37 kHz), and of both methods combination, of organic chlorine by 100mg/L and 200mg/L and de vinegar by 2% and 6%, were studied like alternatives to usual disinfectants. The samples were evaluated regarding the More Probable medium Number of coliforms at 45ºC. Among isolated treatments, the ozonated water and de vinegar by 6% were those with the best result, presenting a reduction concerning at 95% and 100%. The association between ozonated water and ultrasonicwaves presented a reduction at 99.6%. The DCIS at 100mg/L, did not present effect over the microorganisms, but at 200mglL, the reduction was at 64%. The ozone produced an increase of conservation, nevertheless, the ultrasonic waves or the association between methods acceleratedthe conclusion of useful life. The vinegar was that one more prejudicial for the useful life, the found reduction was at 62.2% for the vinegar at 2%, and 100%, for the vinegar at 6%. (AU)