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Combining High-pressure Thermal Treatment (HPTT) and Potassium Sorbate (PS) may have a stronger spore inactivation effect. Spores of Bacillus subtilis were subjected to HPTT at 600 MPa-65 °C/75 °C and a combination of HPTT and PS of 0.1% and 0.2% concentrations. After these treatments, different procedures and techniques were employed to investigate the spore's inactivation. The results revealed that 4.92 ± 0.05 log spores were inactivated after treatment at 600 MPa-75 °C, while 5.97 ± 0.09 log spores were inactivated when the HPTT treatment was combined with 0.2% PS. Changes in permeability of the spore's inner membrane were characterized by OD600 value and release rates of nucleic acids, protein, and dipicolinic acid (DPA). Compared with HPTT treatment at 600 MPa-75 °C, the OD600 value of spores decreased further by about 50% after treatment with a combination of HPTT and 0.2% PS. Additionally, the combined treatments resulted in a significant increase in the OD260 and OD280 values, as well as the DPA release. The spore size analysis indicated a significant decrease in the size of spores treated with a combination of HPTT at 600 MPa-75 °C and PS of 0.2% concentration. Furthermore, the flow cytometry analysis and confocal laser scanning microscopy (CLSM) analysis indicated that the inner membrane damage of spores was higher after combined treatments than that after HPTT treatment alone. A significant reduction was also found in the Na+/K+-ATPase activity after the combined treatments. Also, the FTIR analysis revealed that the combined treatments resulted in significant adverse changes in the spores' inner membrane, cell wall, cortex, and nucleic acid. Therefore, the combination of HPTT and PS has a stronger inactivation effect and can be suggested as a promising strategy for the inactivation of Bacillus subtilis spores.
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Bacillus subtilis , Ácido Sórbico , Bacillus subtilis/metabolismo , Ácido Sórbico/farmacologia , Esporos Bacterianos/metabolismo , Temperatura AltaRESUMO
Alicyclobacillus acidoterrestris can cause spoilage in orange juice that leads to consumer rejection. Six different orange juices were physiochemically characterized (pH, total soluble solids, titratable acidity, total polyphenols and vitamin C). A bottle for each sampling point per juice was filled (headspace: 40% volume) and inoculated with 102 -103 CFU per ml of A. acidoterrestris ATCC® 49025™ (heat shocked before inoculation: 75°C, 20 min). Samples were stored for 21 days at 45 ± 1°C and plate counted periodically on acidified YSG agar (pH 3·7) incubated at 45 ± 1°C for 3 days. The effect of headspace (6% versus 40% volume) on A. acidoterrestris growth was also evaluated. The effect of nisin (0·006, 0·003, 0·0015, and 0·00075%), sodium benzoate (0·1%), potassium sorbate (0·1%) and a mix of benzoate and sorbate (0·05% each) on A. acidoterrestris was additionally addressed. Alicyclobacillus acidoterrestris reached up to 107 CFU per ml in five of the six juices in less than 1 week. Headspace significantly impacted (P < 0·05) A. acidoterrestris maximum population, which reached the critical value of 5 log CFU per ml at 40% headspace. All preservatives, regardless of concentration, showed a bacteriostatic effect during 22 days of storage with no significant differences amongst treatments (P > 0·05).
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Anti-Infecciosos , Citrus sinensis , Nisina , Nisina/farmacologia , Ágar/química , Ácido Sórbico , Benzoato de Sódio , Bebidas , Esporos Bacterianos , Anti-Infecciosos/farmacologia , Ácido Ascórbico/farmacologiaRESUMO
BACKGROUND: The preservatives sorbic acid (SA) and potassium sorbate (PS) are considered rare skin sensitizers. PS-containing products always contain SA to a certain extent, and positivity to PS may reflect sensitization to SA. Their optimal patch-test conditions are unknown. OBJECTIVES: To report on the outcome of testing with SA and PS in various concentrations and/or vehicles. PATIENTS AND METHODS: Seventeen patients with allergic contact dermatitis from PS/SA-containing topical pharmaceuticals and medical devices were patch tested to SA 2% and 5% pet.; SA 1%, 2%, 3%, 5%. eth.; and/or SA 2% aq., whereas PS was patch tested 5% pet. and/or 5% aq. RESULTS: Only one patient, not tested to the ethanol preparations, presented with a (doubtful) positive reaction to SA 2% pet., while this remained negative in 13 patients who reacted to SA 2% eth. The preparations containing SA 5% pet.; 1%, 3%, and 5% eth.; and SA 2% aq. had little or no additional value. PS 5% pet. performed better than 5% aq., and always mirrored SA sensitization. CONCLUSIONS: Sensitization to SA and PS is probably underestimated. SA 2% eth. and PS 5% pet. are preferred for patch testing, and patients sensitized to SA should avoid PS-containing products. HIGHLIGHTS: Potassium sorbate (PS) and sorbic acid (SA) are widely used preservatives. PS-containing products always contain some SA. Both are considered rare skin sensitizers, but contact allergy in response to them might be underestimated. SA 2% eth. and PS 5% pet., rather than SA 2% pet. and PS 5% aq., respectively, may be required to diagnose contact allergy from PS/SA-containing topical pharmaceuticals and medical devices. A positive patch test to PS reflects sensitization to SA, and patients sensitized to SA should also avoid PS-containing products.
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In order to find a new preservation solution for avian coccidial oocysts that can replace potassium dichromate (K2Cr2O7) solution, Eimeria tenella oocysts were preserved in 0.1 to 10% potassium sorbate (C6H7KO2) solution in this study. The results showed that there was no significant difference between the sporulation rate of E. tenella oocysts preserved in 0.1 to 10% C6H7KO2 solution and in 2.5% K2Cr2O7 solution (p > 0.05). The 0.5 to 10% C6H7KO2 solution could also effectively inhibit the growth of bacterial microorganisms. E. tenella oocysts preserved in 1% C6H7KO2 solution at 4 °C for 3, 6, 9, and 12 months, with the oocyst production of E. tenella oocysts being 1.3-, 1.2-, 1.6-, and 1.3-fold higher than that of oocysts stored in 2.5% K2Cr2O7 solution (p < 0.05). In conclusion, C6H7KO2 could replace K2Cr2O7 as the preservation solution of avian coccidial oocysts.
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Eimeria tenella/crescimento & desenvolvimento , Oocistos/crescimento & desenvolvimento , Preservação Biológica , Ácido Sórbico , Animais , Galinhas , Coccidiose , Eimeria , Doenças das Aves Domésticas/parasitologia , Esporos de ProtozoáriosRESUMO
AIMS: To investigate the changes in fermentation quality of whole-plant corn silage ensiled with varying dosages of mixed organic acid salts (MS), and link these dosage changes to shifts in bacterial composition. METHODS AND RESULTS: Fermentation quality and bacterial community of corn silage ensiled with MS at four application rates (0, 0·67 g kg-1 , 1·33 g kg-1 , and 2·00 g kg-1 ) were investigated. The MS consisted of 40% potassium sorbate and 60% sodium benzoate. The corn silages were conserved for 42 days. Dry matter losses and ammonia nitrogen concentration were linearly declined by up to 19·10 and 33·3% with increasing dosages of MS. MS treatments significantly reduced the pH of silage vs the control group. Further analysis indicated that the improvement of fermentation quality was the result of shifts in bacterial composition, the relative abundance of Lactobacillus paralimentarius and Pediococcus spp. increased while Lactobacillus reuteri, Lactobacillus coryniformis and Klebsiella declined with increasing dosages of MS. CONCLUSIONS: MS effectively improved the fermentation quality of whole-plant corn silage with an optimum dosage of 2·00 g kg-1 . SIGNIFICANCE AND IMPACT OF THE STUDY: The correlation between bacterial taxa and fermentation quality provides a potential for the development of novel silage inoculants and for the application of MS on controlling Klebsiella mastitis of livestock farms.
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Microbiota/efeitos dos fármacos , Silagem/microbiologia , Benzoato de Sódio/farmacologia , Ácido Sórbico/farmacologia , Zea mays/microbiologia , Amônia/análise , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Bactérias/metabolismo , Fermentação , Silagem/análiseRESUMO
The present experiment was conducted to evaluate the effect of dietary supplementation with some feed additives (potassium sorbate; Sor, hydrated sodium calcium almuniosilicate; Hsc and L-methionine; L-M) against aflatoxin B1 (AF) toxicity in rabbits. A total of 72 growing rabbits (5-week-old) were distributed into six equal groups (4 replicates with 3 rabbits each). The experimental groups are as follows: control group, AF group (supplemented with AF 0.3 mg/kg diet), AF + Sor group (AF 0.3 mg/kg diet + Sor 2 g/kg diet), AF + Hsc group (AF 0.3 mg/kg diet + Hsc 5 g/kg diet), AF + L-M group (AF 0.3 mg/kg diet + L-M 8 g/kg diet) and AF + Mix group (AF 0.3 mg/kg diet + 2 Sor + 5 Hsc + 8 L-M g/kg diet). Live body weight and weight gain at 13 weeks of age were significantly reduced by AF. Feed intake at 13 weeks of age was decreased in AF, AF + Hsc and AF + Mix compared to the control. AF, AF + Hsc and AF + Mix showed the lowest total antioxidant capacity compared to the control. The highest level of reactive oxygen species and 8-Hydroxy-2-desoxyguanosine was observed in AF group. Using of other supplements with AF increased immunoglobulinM than AF alone. In conclusion, dietary supplementation of Sor, L-M, Hsc or their mixture was effective in reducing the adverse effects of AF on performance, antioxidant and immune status of rabbits with more better improvement obtained by Sor or L-M separately.
Assuntos
Aflatoxina B1/toxicidade , Silicatos de Alumínio/farmacologia , Metionina/farmacologia , Coelhos/crescimento & desenvolvimento , Ácido Sórbico/farmacologia , 8-Hidroxi-2'-Desoxiguanosina/sangue , Silicatos de Alumínio/administração & dosagem , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Contaminação de Alimentos , Imunoglobulina M/sangue , Malondialdeído/sangue , Metionina/administração & dosagem , Coelhos/sangue , Espécies Reativas de Oxigênio/sangue , Ácido Sórbico/administração & dosagemRESUMO
The present trial was conducted to evaluate the beneficial role of some feed additives (potassium sorbate; Sor, hydrated sodium calcium almuniosilicate; Hsc and l-methionine; L-M) in attenuating the hepatic and renal toxicity of aflatoxin B1 (AFB1) in rabbits. A total number of 72 NZW growing rabbits (5 week-old) were divided into six experimental groups (four replicates with three rabbits each) as follows: control group, AFB1 group (supplemented with AFB1 0.3 mg/kg diet), AFB1 + Sor group (AFB1 0.3 mg/kg diet + Sor 2 g/kg diet), AFB1 + Hsc group (AFB1 0.3 mg/kg diet + Hsc 5 g/kg diet), AFB1 + L-M group (AFB1 0.3 mg/kg diet + L-M 8 g/kg diet) and AFB1 + Mix group (AFB1 0.3 mg/kg diet + 2 Sor + 5 Hsc + 8 L-M g/kg diet). Serum levels of total protein, albumin and globulin were significantly reduced by AF. AF increased the serum activity of aspartate aminotransferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) enzymes. While, they were reduced in AF + Sor and AF + Mix groups compared with AF group. AF increased the level of cystatin C and Beta-2 microglobulin (BMG). All other supplements significantly reduced the level of cystatin C than AF; however, this reduction was more pronounced in AF-L-M group. AF + Sor, AF + L-M and AF + Mix equally reduced the BMG level than AF and AF + HSc, however, still higher than control. AF elevated the total cholesterol (TC) and LDL-cholesterol levels. A significant reduction in HDL cholesterol was seen in AF group. Additionally, AF induced pathological alterations in the liver and kidney of exposed rabbits on the other hands, the three additives separately or in mix attenuated the Af-induced alterations. In conclusion, the dietary supplementation of Sor, L-M, Hsc or their mixture was effective in ameliorating the negative effects of AFB1 on liver and kidney function and structure in rabbits with more better improvement obtained by Sor or L-M separately.
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Aflatoxina B1/toxicidade , Silicatos de Alumínio/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/veterinária , Suplementos Nutricionais , Metionina/farmacologia , Ácido Sórbico/farmacologia , Ração Animal/análise , Animais , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Dieta/veterinária , Conservantes de Alimentos/farmacologia , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Nefropatias/veterinária , CoelhosRESUMO
The aim of the present study was to evaluate the use of red propolis extract, as a natural additive, in yogurt. For this, yogurt was produced with red propolis extract (YRP), to replace the additive chemical potassium sorbate, used in the commercial yogurt (CY). Analysis for apparent viscosity, texture and sensorial acceptance were performed. Apparent viscosity and texture measurements of the samples were similar to the control. Sensory evaluation showed that the samples of YRP reached a mean score of 9 on the hedonic scale, the same score found for CY. Regarding the purchase intention, the samples of YRP showed a positive intention by 64.45% of the consumers, and for CY, 68.89%. For the taste, texture, aroma and consistency, the scores were in the range from 8 to 10, for both samples. It can be concluded that the yogurt incorporated with red propolis presents potential for its commercialization in the Brazilian market.
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Composite films containing different amounts of potassium sorbate (KS) were prepared by using fish scale collagen (Col) and polyvinyl alcohol (PVA). Fourier transform infrared spectroscopy (FTIR), light transmittance, mechanical, water vapor transmission rate (WVTR), and the antibacterial properties of the composite films were analyzed. The results showed that the addition of Col significantly reduced the light transmittance of the composite film, but KS had no significant effect on the light transmission. The tensile strength decreased first and then increased with the addition of KS, while the WVTR increased first and then decreased. The composite film exhibited a certain degree of antibacterial properties against E. coli and S. aureus. In addition, we found that ultrasonic treatment reduced the WVTR, and also improved tensile strength and elongation at break of the composite films, but had no significant effect on other properties. The KS/Col/PVA films have the potential to be used as antimicrobial food packaging.
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Escamas de Animais/química , Colágeno/química , Peixes , Membranas Artificiais , Álcool de Polivinil/química , Ácido Sórbico/farmacologia , Ondas Ultrassônicas , Animais , Fenômenos Mecânicos , Ácido Sórbico/química , Análise EspectralRESUMO
A relatively short storage life is considered a major problem for the transportation of strawberries across long distances to markets and for exportation. The aim of this research is to study the combined effects of potassium sorbate and radiation (3 kGy) on the microbial load, shelf life and most of the biochemical constituents such as vitamin C and total soluble solids of strawberries. A potassium sorbate (1%) treatment was combined, in practical application, with irradiation (3 kGy) to extend the shelf life of strawberries. All strawberry samples were stored at 4 ± 1 °C (90-92% RH). Quality assessment of the microbial and biochemical constituents, vitamin C, and TSS during the storage period was performed. The results showed that Gamma irradiation alone at 3 kGy extended the shelf life of strawberries to 21 days. Further extension of the shelf life to 21 days was obtained when irradiation (3 kGy) was combined with potassium sorbate treatment. All treatments caused non-significant decreases in vitamin C content during storage, except for the treatment of strawberries with a solution of potassium sorbate, which caused a significant decrease in the vitamin C content, and a gradual decrease in the vitamin C content occurred with an increase in storage time for all treatments.
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In a previous study, a stable tamarillo sweet product (TSP) was obtained by applying hurdle technology (low pH, reduction of water activity, sodium benzoate addition and stored at 4 °C, with oxygen and light protection). In order to improve the TSP shelf life, it was decided to employ a mixture of antimicrobial agents (sodium benzoate and potassium sorbate 50-50%) and fruit blanching. The phenolic compounds content, total monomeric anthocyanins of TSP, antioxidant capacity, microbial growth (aerobic mesophilic bacteria, molds and yeasts) and net color change were evaluated, during 63 days. The results showed that the use of blanched tamarillo and the addition of the antimicrobial mixture increased the TSP stability, in which the microbial counts were maintained below the limits established by the official food safety norms, without effects the antioxidant compounds and color.
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AIMS: To assess the effect of two temperatures (ambient temperature and 4°C), three preservation methods (no preservative, yoghurt and potassium sorbate), and two periods of storage (3 and 7 days) on Brix and total bacterial and coliform counts of colostrum collected from New Zealand dairy farms. METHODS: One litre of colostrum destined to be fed to newborn calves was collected from 55 New Zealand dairy farms in the spring of 2015. Six aliquots of 150 mL were obtained from each colostrum sample, with two aliquots left untreated, two treated with potassium sorbate and two with yoghurt, and one of each pair of aliquots stored at ambient temperature and the other at 4°C. All samples were tested for Brix, total bacterial counts and coliform counts before treatment (Day 0), and after 3 and 7 days of storage. The effect of preservation method and storage temperature on the change in Brix, bacterial and coliform counts after 3 or 7 days of storage was analysed using multivariable random effects models. RESULTS: For all outcome variables there was a temperature by preservation interaction. For aliquots preserved with potassium sorbate, changes in Brix and bacterial counts did not differ between aliquots stored at ambient temperature or 4°C, but for aliquots preserved with yoghurt or no preservative the decrease in Brix and increase in bacterial counts was greater for aliquots stored at ambient temperature than 4°C (p<0.001). For aliquots preserved with potassium sorbate, coliform counts decreased at both temperatures, but for aliquots preserved with yoghurt or no preservative coliform counts increased for aliquots stored at 4°C, but generally decreased at ambient temperatures (p<0.001). There was also an interaction between duration of storage and temperature for bacterial counts (p<0.001). The difference in the increase in bacterial counts between aliquots stored at 4°C and ambient temperature after 3 days was greater than between aliquots stored at 4°C and ambient temperature after 7 days. CONCLUSIONS AND CLINICAL RELEVANCE: Use of potassium sorbate to preserve colostrum for 3 or 7 days resulted in little or no reduction in Brix and a lower increase in total bacterial counts than colostrum stored without preservative or with yoghurt added. Colostrum quality was not affected by storage temperature for samples preserved with potassium sorbate, but storage at 4°C resulted in better quality colostrum than storage at ambient temperatures for colostrum with no preservative or yoghurt added.
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Colostro/fisiologia , Armazenamento de Alimentos/métodos , Animais , Carga Bacteriana/veterinária , Bovinos , Colostro/imunologia , Colostro/microbiologia , Fazendas , Feminino , Armazenamento de Alimentos/normas , Imunoglobulina G/análise , Nova Zelândia , Gravidez , TemperaturaRESUMO
Sodium benzoate and potassium sorbate are extremely useful agents for food and beverage preservation, yet concerns remain over their complete safety. Benzoate can react with the ascorbic acid in drinks to produce the carcinogen benzene. A few children develop allergy to this additive while, as a competitive inhibitor of D-amino acid oxidase, benzoate can also influence neurotransmission and cognitive functioning. Model organism and cell culture studies have raised some issues. Benzoate has been found to exert teratogenic and neurotoxic effects on zebrafish embryos. In addition, benzoate and sorbate are reported to cause chromosome aberrations in cultured human lymphocytes; also to be potently mutagenic toward the mitochondrial DNA in aerobic yeast cells. Whether the substantial human consumption of these compounds could significantly increase levels of such damages in man is still unclear. There is no firm evidence that it is a risk factor in type 2 diabetes. The clinical administration of sodium benzoate is of proven benefit for many patients with urea cycle disorders, while recent studies indicate it may also be advantageous in the treatment of multiple sclerosis, schizophrenia, early-stage Alzheimer's disease and Parkinson's disease. Nevertheless, exposure to high amounts of this agent should be approached with caution, especially since it has the potential to generate a shortage of glycine which, in turn, can negatively influence brain neurochemistry. We discuss here how a small fraction of the population might be rendered-either through their genes or a chronic medical condition-particularly susceptible to any adverse effects of sodium benzoate.
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Oxidative stress has the main role in protein conformational changes and consequent direct involvement in different kind of diseases. Potassium sorbate as a widespread industrial preservative and glucose are two important oxidants that can be involved in oxidative stress. In this study the effect of ellagic acid as a phenolic antioxidant on amyloid fibril formation of human serum albumin upon incubation of potassium sorbate and glucose was studied using thioflavin T assay, surface tension, atomic force microscopy, Amadori product, and carbonyl content assays. The thioflavin T assay and atomic force microscopy micrographs demonstrated the antiamyloidogenic effect of ellagic acid on the human serum albumin fibril formation. This antioxidant also had the repair effect on surface tension of the modified human serum albumin (amyloid intermediates), which was destructed, caused by potassium sorbate and glucose. This mechanism takes place because of potent carbonyl stress suppression effect of ellagic acid, which was strengthening by potassium sorbate in the presence and absence of glucose.
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Ácido Elágico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Albumina Sérica/efeitos dos fármacos , Glucose/efeitos adversos , Glicosilação , Humanos , Conformação Proteica , Albumina Sérica/química , Albumina Sérica/ultraestrutura , Ácido Sórbico/efeitos adversos , Tensão Superficial/efeitos dos fármacosRESUMO
The objective of this experiment was to evaluate the effect of a chemical additive on the fermentation and aerobic stability of high-moisture corn (HMC). Ground HMC (~63% dry matter) was untreated, or treated with an additive containing sodium benzoate, potassium sorbate, and sodium nitrite as active ingredients, at 0, 2, 3, or 4 L/t of fresh matter. Laboratory silos (7.5 L) were prepared and ensiled for 21 and 90d (4 silos/treatment per d of ensiling). Small bag silos were prepared for untreated HMC and HMC treated with 4 L/t of the additive and analyzed for nitrate-N and nitrite-N after 0, 3, and 7d of ensiling. The concentration of nitrate-N was similar between these 2 treatments and was below levels considered problematic for ruminants. Nitrite-N was greater in HMC treated with the high level of additive but was also very low for both treatments. Numbers of yeasts were similar among treatments in fresh HMC and decreased substantially after ensiling. Numbers of yeasts were similar among treatments after 21d of ensiling but after 90d they were lower in treated versus untreated HMC. Concentrations of organic acids (lactic, acetic, and propionic) and pH were not different among treatments at any time of ensiling. In contrast, treatment with the additive markedly decreased the concentration of ethanol in HMC after 21 and 90d when compared with untreated HMC. Treatment with all levels of the additive markedly improved the aerobic stability and improved the recovery of dry matter compared with untreated HMC. Overall, our findings suggest that the chemical additive used in this study has the potential to improve the fermentation and aerobic stability of HMC after a relatively short period (21d) and after a moderate length (90d) of ensiling.
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Fermentação , Zea mays/química , Silagem/análise , Silagem/microbiologia , Benzoato de Sódio/análise , Nitrito de Sódio/análise , Ácido Sórbico/análise , Leveduras/isolamento & purificação , Zea mays/microbiologiaRESUMO
AIM: To investigate the cytotoxicity of a modified salt solution (MSS) and evaluate the antimicrobial properties of MSS on in vitro biofilm models. METHODOLOGY: In a metabolic assay, fibroblasts derived from periodontal ligaments (PDL) of human extracted teeth were cultured and challenged with MSS or controls. Then, in active attachment biofilm models, the efficacy of MSS in the presence of dentine powder and in eliminating mature biofilms was investigated. In the dentine assay, a biofilm of Enterococcus faecalis was employed. For the final assay, microorganisms were retrieved from infected root canals and cultured to produce biofilms. After the treatments with MSS or the controls, the biofilms were collected, serially diluted and plated. The colony-forming units were counted. One-way anova was used to analyse the differences between the groups. A P < 0.05 was considered significant. RESULTS: The PDL fibroblasts remained metabolically active after challenges with MSS. Dentine powder did not alter the efficacy of MSS (P > 0.05). In endodontic biofilms, the culturable bacteria were equally reduced by MSS, 2% chlorhexidine (CHX) or 2% sodium hypochlorite (NaOCl) (P > 0.05). CONCLUSIONS: Modified salt solution is noncytotoxic in vitro and has good antimicrobial properties equal to CHX and NaOCl. Although the results are promising, ex vivo and in vivo studies are needed before its use as an interappointment root canal dressing can be considered.
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Anti-Infecciosos Locais/farmacologia , Biofilmes/efeitos dos fármacos , Cavidade Pulpar/efeitos dos fármacos , Cavidade Pulpar/microbiologia , Dentina/efeitos dos fármacos , Desinfecção/métodos , Irrigantes do Canal Radicular/farmacologia , Sais de Tetrazólio/farmacologia , Células Cultivadas , Clorexidina/farmacologia , Contagem de Colônia Microbiana , Enterococcus faecalis , Fibroblastos , Humanos , Técnicas In Vitro , Hipoclorito de Sódio/farmacologia , SoluçõesRESUMO
The objective of this work was to evaluate the effects of biological and chemical silage additives on the production of volatile organic compounds (VOC; methanol, ethanol, 1-propanol, methyl acetate, and ethyl acetate) within corn silage. Recent work has shown that silage VOC can contribute to poor air quality and reduce feed intake. Silage additives may reduce VOC production in silage by inhibiting the activity of bacteria or yeasts that produce them. We produced corn silage in 18.9-L bucket silos using the following treatments: (1) control (distilled water); (2) Lactobacillus buchneri 40788, with 400,000 cfu/g of wet forage; (3) Lactobacillus plantarum MTD1, with 100,000 cfu/g; (4) a commercial buffered propionic acid-based preservative (68% propionic acid, containing ammonium and sodium propionate and acetic, benzoic, and sorbic acids) at a concentration of 1 g/kg of wet forage (0.1%); (5) a low dose of potassium sorbate at a concentration of 91 mg/kg of wet forage (0.0091%); (6) a high dose of potassium sorbate at a concentration of 1g/kg of wet forage (0.1%); and (7) a mixture of L. plantarum MTD1 (100,000 cfu/g) and a low dose of potassium sorbate (91 mg/kg). Volatile organic compound concentrations within silage were measured after ensiling and sample storage using a headspace gas chromatography method. The high dose of potassium sorbate was the only treatment that inhibited the production of multiple VOC. Compared with the control response, it reduced ethanol by 58%, ethyl acetate by 46%, and methyl acetate by 24%, but did not clearly affect production of methanol or 1-propanol. The effect of this additive on ethanol production was consistent with results from a small number of earlier studies. A low dose of this additive does not appear to be effective. Although it did reduce methanol production by 24%, it increased ethanol production by more than 2-fold and did not reduce the ethyl acetate concentration. All other treatments increased ethanol production at least 2-fold relative to the control, and L. buchneri addition also increased the 1-propanol concentration to approximately 1% of dry matter. No effects of any treatments on fiber fractions or protein were observed. However, L. buchneri addition resulted in slightly more ammonia compared with the control. If these results hold under different conditions, a high dose of potassium sorbate will be an effective treatment for reducing VOC production in and emission from silage. Regulations aimed at reducing VOC emission could be ineffective or even increase emission if they promote silage additives without recognition of different types of additives.
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Etanol/metabolismo , Silagem/análise , Ácido Sórbico/farmacologia , Compostos Orgânicos Voláteis/metabolismo , 1-Propanol/metabolismo , Ração Animal , Animais , Bactérias/química , Bactérias/efeitos dos fármacos , Fibras na Dieta , Ésteres/metabolismo , Lactobacillus/química , Lactobacillus/efeitos dos fármacos , Silagem/microbiologia , Leveduras/química , Leveduras/efeitos dos fármacos , Zea maysRESUMO
Kunda, an indigenous heat desiccated sweet product prepared from milk and added sugar, has a shelf-life of a few days under market conditions. In this study, effect of preservatives viz. potassium sorbate and nisin on the shelf-life of kunda stored at 30° and 5 °C was investigated. During storage, several changes took place in physico-chemical and sensory characteristics, the changes being faster at 30° than at 5 °C. There was little effect of preservatives per se on the quality of kunda, but changes were slower in kunda preserved with nisin. Kunda packaged in LDPE pouches or tin cans and stored at 30° and 5 °C, irrespective of the presence or absence of preservatives, was stable for 42 and 90 days respectively. Increase in osmotic pressure due to high levels of sugar in kunda might be responsible for containing the growth of microbes in the product.
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The present investigation was undertaken to study the effect of treatments and packaging on the quality of dried carrot slices during storage. Carrot cultivar 'Nantes' was sliced into 4.5 mm thick slices which were blanched in water at 95 °C for 4 min followed by dipping in 6% potassium metabisulphite (KMS) solution for 40 min and 350 ppm potassium sorbate solution for 10 min prior to two stage phase drying i.e. at 90 ± 5 °C for 2 h and further drying at 60 ± 5 °C for 7 h in a cross-flow hot air cabinet dryer. The dried carrot slices were packed in 50 g packages of aluminium foil laminate (AFL) (polyethylene, aluminium foil and polyester) and high density polyethylene (HDPE) pouches having 32.5 µm and 56.0 µm thickness respectively and stored under ambient conditions i.e.18.5-29.1 °C temperature and 44.4-60.4% relative humidity for 6 months. Significant (p ≤ 0.05) increase was observed in the moisture content, water activity, reducing sugars and non-enzymatic browning while total solids, total soluble solids, titratable acidity, ascorbic acid, total sugars, pectin, rehydration ratio, sulphur dioxide, sorbic acid and carotenoids decreased significantly (p ≤ 0.05) during storage. Carrot slices pre-treated with 6% KMS and packed in AFL pouches were found to retain best physico-chemical quality. The curried product and soup prepared from dried slices from the same had highly acceptable sensory quality with initial overall acceptability scores 8.2 and 8.5 for curried slices and soup respectively on 9-point hedonic scale. The overall acceptability scores decreased from 8.2 to 7.9 and 8.5 to 7.7 in curried product and soup respectively after 6 months storage. All the samples were microbially safe during 6 months of storage.
RESUMO
Despite the advantages of surgical handrub in terms of the ease of application and effectiveness, chlorhexidine (CHG)-based hand scrubbing remains the preferred method for surgical hand preparation. However, it does not systematically meet the non-inferiority requirement of the European norm (EN) 12791 with respect to n-propanol (the reference product) and does not provide the sustained efficacy expected for these long-lasting agents. Commercially available alcohol-based products have also failed to demonstrate sustained efficacy according to EN 12791. Multi-step protocols enhance the efficacy of hand scrubbing, yet their extended disinfection duration might diminish their allure for healthcare professionals. In this study, we show that hand scrubbing with CHG 4% followed by a 1 min rubbing with the novel formulation of ethanol (Et) 70%/CHG 3% plus 0.3% potassium sorbate food additive (PS) meets the non-inferiority requirement and demonstrates sustained efficacy when tested according to EN 12791. The immediate and 3 h effect of this protocol was significantly higher than that of n-propanol and the homologous disinfection protocol without PS (CHG 4% hand scrub plus Et 70%/CHG 3% rub), demonstrating that the inclusion of PS confers a notable residual effect. We speculate that this non-volatile ingredient acts synergistically with CHG. This promising combination represents an alternative method for the development of new disinfection strategies.