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1.
Foods ; 13(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611283

RESUMO

The total phenolic, flavonoid, and anthocyanin contents were evaluated in 11 cultivars of Argentinian roses of different colors. HPLC-ESI-QTOF/MS was used to identify the components where ellagic and quinic acids, quercetin, and kaempferol glycosylated derivatives were found. The phenolic contents ranged from 78.8 ± 3.2 to 203.4 ± 3.1 mg GAE/g dw, the flavonoid content ranged from 19.1 ± 3.8 to 125.9 ± 6.5 mg QE/g dw, and the anthocyanin content ranged from less than 0.01 to 5.8 ± 0.1 mg CE/g dw. The dark red cultivars exhibited the greatest levels of the analyzed compounds and of the antioxidant activities, even higher than those of certain plants known for their high phenolic contents and antioxidant activity. Moreover, the addition of these extracts decreased the population of L. innocua and P. aeruginosa to undetectable levels 24 h after inoculation. Rose petal extracts, mainly those with a dark red color, can be used as natural additives in food, feed, and cosmetics, as they contain a high proportion of bioactive compounds with antioxidant and antimicrobial effects.

4.
Foods ; 12(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38002185

RESUMO

The effect of essential oils (EOs) incorporated in their vapor phase combined with lactic acid immersion pretreatment was studied on fresh refrigerated chicken breast shelf life. Among the several EOs assayed, the in vitro results obtained from the vapor diffusion test allowed mustard, oregano, and garlic EOs to be selected due to their higher antimicrobial activity. In addition, it was possible to determine the EO minimum inhibitory concentrations against Pseudomonas aeruginosa and Escherichia coli and to identify EO binary mixtures showing synergistic or additive effects. Based on the obtained results, a ternary mixture constituted by 0.073, 0.292, and 0.146 µL/mL of headspace of mustard, oregano, and garlic, respectively, was proposed for its application to chicken breasts. The ternary mixture inhibitory action was confirmed in vitro against P. aeruginosa and E. coli. Furthermore, the presence of numerous compounds with recognized antimicrobial and antioxidant activity was found in its volatile phase through gas chromatography. When applying an EO mixture in its vapor phase in combination with 1.0% v/v of lactic acid immersion pretreatment on refrigerated chicken breast, a decrease in mesophilic microorganisms' growth rate as well as in lipid oxidation was observed. Moreover, in a preliminary sensory test, the treated chicken breast was found to be acceptable to consumers and showed no significant differences compared to untreated chicken. In conclusion, the combined use of lactic acid immersion and EOs in their vapor phase was an effective alternative to increase chicken breast shelf life.

5.
Open Forum Infect Dis ; 10(10): ofad485, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37869403

RESUMO

Background: To assist clinicians with identifying children at risk of severe outcomes, we assessed the association between laboratory findings and severe outcomes among severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected children and determined if SARS-CoV-2 test result status modified the associations. Methods: We conducted a cross-sectional analysis of participants tested for SARS-CoV-2 infection in 41 pediatric emergency departments in 10 countries. Participants were hospitalized, had laboratory testing performed, and completed 14-day follow-up. The primary objective was to assess the associations between laboratory findings and severe outcomes. The secondary objective was to determine if the SARS-CoV-2 test result modified the associations. Results: We included 1817 participants; 522 (28.7%) SARS-CoV-2 test-positive and 1295 (71.3%) test-negative. Seventy-five (14.4%) test-positive and 174 (13.4%) test-negative children experienced severe outcomes. In regression analysis, we found that among SARS-CoV-2-positive children, procalcitonin ≥0.5 ng/mL (adjusted odds ratio [aOR], 9.14; 95% CI, 2.90-28.80), ferritin >500 ng/mL (aOR, 7.95; 95% CI, 1.89-33.44), D-dimer ≥1500 ng/mL (aOR, 4.57; 95% CI, 1.12-18.68), serum glucose ≥120 mg/dL (aOR, 2.01; 95% CI, 1.06-3.81), lymphocyte count <1.0 × 109/L (aOR, 3.21; 95% CI, 1.34-7.69), and platelet count <150 × 109/L (aOR, 2.82; 95% CI, 1.31-6.07) were associated with severe outcomes. Evaluation of the interaction term revealed that a positive SARS-CoV-2 result increased the associations with severe outcomes for elevated procalcitonin, C-reactive protein (CRP), D-dimer, and for reduced lymphocyte and platelet counts. Conclusions: Specific laboratory parameters are associated with severe outcomes in SARS-CoV-2-infected children, and elevated serum procalcitonin, CRP, and D-dimer and low absolute lymphocyte and platelet counts were more strongly associated with severe outcomes in children testing positive compared with those testing negative.

6.
NAR Genom Bioinform ; 5(3): lqad073, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37608803

RESUMO

Multiple displacement amplification (MDA) has proven to be a useful technique for obtaining large amounts of DNA from tiny samples in genomics and metagenomics. However, MDA has limitations, such as amplification artifacts and biases that can interfere with subsequent quantitative analysis. To overcome these challenges, alternative methods and engineered DNA polymerase variants have been developed. Here, we present new MDA protocols based on the primer-independent DNA polymerase (piPolB), a replicative-like DNA polymerase endowed with DNA priming and proofreading capacities. These new methods were tested on a genomes mixture containing diverse sequences with high-GC content, followed by deep sequencing. Protocols relying on piPolB as a single enzyme cannot achieve competent amplification due to its limited processivity and the presence of ab initio DNA synthesis. However, an alternative method called piMDA, which combines piPolB with Φ29 DNA polymerase, allows proficient and faithful amplification of the genomes. In addition, the prior denaturation step commonly performed in MDA protocols is dispensable, resulting in a more straightforward protocol. In summary, piMDA outperforms commercial methods in the amplification of genomes and metagenomes containing high GC sequences and exhibits similar profiling, error rate and variant determination as the non-amplified samples.

7.
Cureus ; 15(7): e42370, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37621804

RESUMO

Robotic surgery (RS) is an evolution of minimally invasive surgery that combines medical science, robotics, and engineering. The first robots approved by the Food and Drug Administration (FDA) were the Da Vinci Surgical System and the ZEUS Robotic Surgical System, which have been improving over time. Through the decades, the equipment applied to RS had undergone a wide transformation as a response to the development of new techniques and facilities for the assembly and implementation of the own. RS has revolutionized the field of urology, enabling surgeons to perform complex procedures with greater precision and accuracy, and many other surgical specialties such as gynecology, general surgery, otolaryngology, cardiothoracic surgery, and neurosurgery. Several benefits, such as a better approach to the surgical site, a three-dimensional image that improves depth perception, and smaller scars, enhance range of motion, allowing the surgeon to conduct more complicated surgical operations, and reduced postoperative complications have made robotic-assisted surgery an increasingly popular approach. However, some points like the cost of surgical procedures, equipment-instrument, and maintenance are important aspects to consider. Machine learning will likely have a role to play in surgical training shortly through "automated performance metrics," where algorithms observe and "learn" individual surgeons' techniques, assess performance, and anticipate surgical outcomes with the potential to individualize surgical training and aid decision-making in real time.

8.
Sci Rep ; 13(1): 5205, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997546

RESUMO

The autochthonous strain Latilactobacillus sakei sp. sakei ACU-2 was selected as a meat starter culture for dry sausage production. Transferring this strain from laboratory scale to industry requires an increase in biomass production, while lowering process costs. In this study, a combination of techniques was applied in order to optimize the culture medium composition to enhance biomass production of L. sakei ACU-2. One variable at a time experiments, Plackett-Burman design, and mixture design were performed to fulfill the strain nutritional requirements. Eventually, the optimized formulation contained 19.46 g/L yeast extract; 8.28 g/L whey protein concentrate; 2.26 g/L soy peptone; 30 g/L cerelose; 1 g/L Tween 80; 5 g/L sodium acetate; 0.2 g/L magnesium sulfate and 0.05 g/L manganese sulfate. When L. sakei ACU-2 was cultivated in a bioreactor using the alternative medium, an enhancement of 75.5% of biomass production was achieved, in comparison to its growth in the commercial de Man, Rogosa, and Sharpe medium. Furthermore, a reduction of 62-86% of the cost was also attained. These results support a promising large-scale application of the designed medium for high biomass yields of the starter culture at minor costs.


Assuntos
Latilactobacillus sakei , Produtos da Carne , Humanos , Biomassa , Carne , Reatores Biológicos , Fermentação
9.
Antioxidants (Basel) ; 12(3)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36978929

RESUMO

The effect of freeze and hot air drying methods on the retention of total phenolics, antioxidant activity (AA), and color of different cultivars of rose petals was analyzed. Both methods similarly preserved the phenolic content and AA, while freeze drying showed better red color retention. Furthermore, the conditions of total phenolics and AA extraction from two rose cultivars, Lovely Red and Malu, were optimized by response surface methodology through a Box-Behnken design. The solvent exhibited a major effect on the total phenolic content (TPC) and AA. The selected parameters were ethanol 38%, 75 °C, and 30 min. Under these conditions, the predicted values for Lovely Red were 189.3 mg GA/g dw (TPC) and 535.6 mg Trolox/g dw (AA), and those for Malu were 108.5 mg GA/g dw (TPC) and 320.7 mg Trolox/g dw (AA). The experimental values were close to the predicted values, demonstrating the suitability of the model. Ultrasound-assisted extraction increased the AA of the extracts but not the TPC. Fifteen compounds were identified in the Lovely Red cultivar, with no differences between the two drying methods. The results obtained suggest that the analyzed cultivars, particularly the red ones, can be considered a natural source of powerful antioxidant compounds.

10.
Food Chem (Oxf) ; 6: 100163, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-36698371

RESUMO

The aim of this study was to determine the evolution of total phenolic content and antioxidant activity during controlled fermentation of three different Brassicaceae and compare it with spontaneous fermentations. The two-step controlled fermentation was carried out with lactic acid bacteria selected by their biotechnological properties. The selected bacteria were genotypically identified as Leuconostoc mesenteroides ssp. jonggajibkimchii, Ln. mesenteroides ssp. dextranicum, Lactiplantibacillus plantarum ssp. argentoratensis, L. plantarum and L. pentosus. The total phenolic content did not show a trend when comparing the different fermentations; it depended on the type of extract and vegetable. The controlled fermentation exhibited higher antioxidant activity than spontaneous fermentations for all the vegetables during the process. The extracts of red cabbage exhibited a total phenolic content and antioxidant activity higher than chinese and white cabbage, regardless of the type of fermentation.

11.
Foods ; 11(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36359975

RESUMO

The development of biodegradable packaging materials has become a widely addressed topic in recent years. Microparticles generated from Brassica oleracea var. capitata f. rubra (red cabbage, RC) and Beta vulgaris L. var. conditiva (beetroot, BR) which contained anthocyanins or betalains, were included in the formulation of edible films based on cassava starch (CS) giving origin to films CSRC, CSBR, or CSBC (mixture of both particles). The inclusion of the filler determined an increase in the stress at rupture from 0.8 MPa (CS) to 1.2 MPa (CSRC) or 1.0 MPa (CSBC), of the contact angle from 2.6° to 13.8° (CSBR) or 19.6° (CSBC). The use of these films for developing a smart label for hake packaging and the study of the TBV-N content, the microbiological characteristics of the muscle, and the color changes of the label with time, allowed us to conclude that the films CSRC and CSBC would be suitable for sensing the deterioration of packaged and chilled hake and that the color change of the label CSBC was completely consistent with fish muscle deterioration. As the microparticles can be obtained from by-products of the production and industrialization of plant tissues, the composite films and the smart labels developed can contribute not only to the development of safe food but also to the addition of value to those residues and to environmental protection.

12.
JAMA Netw Open ; 5(7): e2223253, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35867061

RESUMO

Importance: Little is known about the risk factors for, and the risk of, developing post-COVID-19 conditions (PCCs) among children. Objectives: To estimate the proportion of SARS-CoV-2-positive children with PCCs 90 days after a positive test result, to compare this proportion with SARS-CoV-2-negative children, and to assess factors associated with PCCs. Design, Setting, and Participants: This prospective cohort study, conducted in 36 emergency departments (EDs) in 8 countries between March 7, 2020, and January 20, 2021, included 1884 SARS-CoV-2-positive children who completed 90-day follow-up; 1686 of these children were frequency matched by hospitalization status, country, and recruitment date with 1701 SARS-CoV-2-negative controls. Exposure: SARS-CoV-2 detected via nucleic acid testing. Main Outcomes and Measures: Post-COVID-19 conditions, defined as any persistent, new, or recurrent health problems reported in the 90-day follow-up survey. Results: Of 8642 enrolled children, 2368 (27.4%) were SARS-CoV-2 positive, among whom 2365 (99.9%) had index ED visit disposition data available; among the 1884 children (79.7%) who completed follow-up, the median age was 3 years (IQR, 0-10 years) and 994 (52.8%) were boys. A total of 110 SARS-CoV-2-positive children (5.8%; 95% CI, 4.8%-7.0%) reported PCCs, including 44 of 447 children (9.8%; 95% CI, 7.4%-13.0%) hospitalized during the acute illness and 66 of 1437 children (4.6%; 95% CI, 3.6%-5.8%) not hospitalized during the acute illness (difference, 5.3%; 95% CI, 2.5%-8.5%). Among SARS-CoV-2-positive children, the most common symptom was fatigue or weakness (21 [1.1%]). Characteristics associated with reporting at least 1 PCC at 90 days included being hospitalized 48 hours or more compared with no hospitalization (adjusted odds ratio [aOR], 2.67 [95% CI, 1.63-4.38]); having 4 or more symptoms reported at the index ED visit compared with 1 to 3 symptoms (4-6 symptoms: aOR, 2.35 [95% CI, 1.28-4.31]; ≥7 symptoms: aOR, 4.59 [95% CI, 2.50-8.44]); and being 14 years of age or older compared with younger than 1 year (aOR, 2.67 [95% CI, 1.43-4.99]). SARS-CoV-2-positive children were more likely to report PCCs at 90 days compared with those who tested negative, both among those who were not hospitalized (55 of 1295 [4.2%; 95% CI, 3.2%-5.5%] vs 35 of 1321 [2.7%; 95% CI, 1.9%-3.7%]; difference, 1.6% [95% CI, 0.2%-3.0%]) and those who were hospitalized (40 of 391 [10.2%; 95% CI, 7.4%-13.7%] vs 19 of 380 [5.0%; 95% CI, 3.0%-7.7%]; difference, 5.2% [95% CI, 1.5%-9.1%]). In addition, SARS-CoV-2 positivity was associated with reporting PCCs 90 days after the index ED visit (aOR, 1.63 [95% CI, 1.14-2.35]), specifically systemic health problems (eg, fatigue, weakness, fever; aOR, 2.44 [95% CI, 1.19-5.00]). Conclusions and Relevance: In this cohort study, SARS-CoV-2 infection was associated with reporting PCCs at 90 days in children. Guidance and follow-up are particularly necessary for hospitalized children who have numerous acute symptoms and are older.


Assuntos
COVID-19 , Doença Aguda , COVID-19/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Fadiga , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , SARS-CoV-2
13.
Enferm Clin (Engl Ed) ; 32(3): 203-209, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35562010

RESUMO

Kounis syndrome (KS) is defined as the occurrence of a coronary event secondary to a severe allergic reaction. This syndrome is described as poorly known, underdiagnosed and with a low prevalence whose aetiology is difficult to know due to the large number of causative agents. The objective is to create an individualized care plan for a patient with Kounis syndrome. The nursing assessment was performed on admission using Virginia Henderson's need theory. A care plan was developed following the NANDA-NOC-NIC taxonomy. After the planning and execution phase, the proposed activities were evaluated, thus verifying that the objectives had been achieved.


Assuntos
Síndrome de Kounis , Humanos , Síndrome de Kounis/diagnóstico , Síndrome de Kounis/etiologia
14.
J Sci Food Agric ; 102(14): 6727-6736, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35622938

RESUMO

BACKGROUND: Salad dressing formulations include a pH within 3.2-4.1, salt and other solutes to depress water activity. The interaction between hydrocolloids and other components such as humectants determines their physical and microbiological stability. To our knowledge, the effect of commonly used solutes on physical stability and rheological characteristics of oil-in-water emulsions stabilized by xanthan gum has not been reported, and neither has the effect of a spoilage yeast on physical stability been evaluated. RESULTS: The effect of different humectants (sodium chloride, glucose and xylitol) and Zygosaccharomyces bailii inoculation on the stability of oil-in-water emulsions containing different levels of xanthan gum to emulate different types of salad dressings was investigated by means of droplet size, zeta potential, rheological measurements and confocal laser scanning microscopy (CLSM). Generally, the addition of humectants strengthened the weak or strong emulsion structure, especially xylitol. Glucose or xylitol acted as stabilizers since they decreased Sauter and De Broucker diameter. On the contrary, NaCl destabilized the emulsions since it increased droplet size and exhibited the lowest absolute values of zeta potential. Inoculation with Z. bailii destabilized some emulsions since it increased Sauter and De Broucker diameter. Emulsion droplet size, polydispersity, and xanthan gum and yeast location were confirmed by CLSM imaging. CONCLUSION: This study highlights the key role of humectants and xanthan gum level on physical characteristics and stability of oil-in-water emulsions. Addition of xylitol leads to an enhancement in emulsion rheology and physical stability, suggesting that it is a potential low-calorie multifunctional additive for salad dressings. © 2022 Society of Chemical Industry.


Assuntos
Higroscópicos , Cloreto de Sódio , Condimentos , Emulsões/química , Glucose , Reologia , Saccharomyces cerevisiae , Saccharomycetales , Soluções , Água/química , Xilitol
15.
Enferm. clín. (Ed. impr.) ; 32(3): 203-209, May.-Jun. 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-206149

RESUMO

Se define síndrome de Kounis como la aparición de un evento coronario secundario a una reacción alérgica grave. Se describe como una patología poco conocida, infradiagnosticada, con una prevalencia baja y en la que resulta difícil conocer la etiología por la gran cantidad de agentes causales que existen. El objetivo es realizar un plan de cuidados individualizado para un paciente con síndrome de Kounis. La valoración de enfermería se realizó en el ingreso según las necesidades básicas de Virginia Henderson y se elaboró un plan de cuidados siguiendo la taxonomía NANDA-NOC-NIC. Tras la fase de planificación y ejecución, se llevó a cabo la evaluación de las actividades propuestas comprobándose que se habían alcanzado los objetivos.(AU)


Kounis syndrome is defined as the occurrence of a coronary event secondary to a severe allergic reaction. This syndrome is described as poorly known, underdiagnosed and with a low prevalence whose aetiology is difficult to know due to the large number of causative agents. The objective is to create an individualized care plan for a patient with Kounis syndrome. The nursing assessment was performed on admission using Virginia Henderson's need theory. A care plan was developed following the NANDA-NOC-NIC taxonomy. After the planning and execution phase, the proposed activities were evaluated, thus verifying that the objectives had been achieved.(AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Kounis/diagnóstico , Síndrome de Kounis/etiologia , Hipersensibilidade , Anafilaxia , Cuidados de Enfermagem , Enfermagem , Serviço Hospitalar de Emergência
16.
JAMA Netw Open ; 5(1): e2142322, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-35015063

RESUMO

Importance: Severe outcomes among youths with SARS-CoV-2 infections are poorly characterized. Objective: To estimate the proportion of children with severe outcomes within 14 days of testing positive for SARS-CoV-2 in an emergency department (ED). Design, Setting, and Participants: This prospective cohort study with 14-day follow-up enrolled participants between March 2020 and June 2021. Participants were youths aged younger than 18 years who were tested for SARS-CoV-2 infection at one of 41 EDs across 10 countries including Argentina, Australia, Canada, Costa Rica, Italy, New Zealand, Paraguay, Singapore, Spain, and the United States. Statistical analysis was performed from September to October 2021. Exposures: Acute SARS-CoV-2 infection was determined by nucleic acid (eg, polymerase chain reaction) testing. Main Outcomes and Measures: Severe outcomes, a composite measure defined as intensive interventions during hospitalization (eg, inotropic support, positive pressure ventilation), diagnoses indicating severe organ impairment, or death. Results: Among 3222 enrolled youths who tested positive for SARS-CoV-2 infection, 3221 (>99.9%) had index visit outcome data available, 2007 (62.3%) were from the United States, 1694 (52.6%) were male, and 484 (15.0%) had a self-reported chronic illness; the median (IQR) age was 3 (0-10) years. After 14 days of follow-up, 735 children (22.8% [95% CI, 21.4%-24.3%]) were hospitalized, 107 (3.3% [95% CI, 2.7%-4.0%]) had severe outcomes, and 4 children (0.12% [95% CI, 0.03%-0.32%]) died. Characteristics associated with severe outcomes included being aged 5 to 18 years (age 5 to <10 years vs <1 year: odds ratio [OR], 1.60 [95% CI, 1.09-2.34]; age 10 to <18 years vs <1 year: OR, 2.39 [95% CI 1.38-4.14]), having a self-reported chronic illness (OR, 2.34 [95% CI, 1.59-3.44]), prior episode of pneumonia (OR, 3.15 [95% CI, 1.83-5.42]), symptoms starting 4 to 7 days prior to seeking ED care (vs starting 0-3 days before seeking care: OR, 2.22 [95% CI, 1.29-3.82]), and country (eg, Canada vs US: OR, 0.11 [95% CI, 0.05-0.23]; Costa Rica vs US: OR, 1.76 [95% CI, 1.05-2.96]; Spain vs US: OR, 0.51 [95% CI, 0.27-0.98]). Among a subgroup of 2510 participants discharged home from the ED after initial testing and who had complete follow-up, 50 (2.0%; 95% CI, 1.5%-2.6%) were eventually hospitalized and 12 (0.5%; 95% CI, 0.3%-0.8%) had severe outcomes. Compared with hospitalized SARS-CoV-2-negative youths, the risk of severe outcomes was higher among hospitalized SARS-CoV-2-positive youths (risk difference, 3.9%; 95% CI, 1.1%-6.9%). Conclusions and Relevance: In this study, approximately 3% of SARS-CoV-2-positive youths tested in EDs experienced severe outcomes within 2 weeks of their ED visit. Among children discharged home from the ED, the risk was much lower. Risk factors such as age, underlying chronic illness, and symptom duration may be useful to consider when making clinical care decisions.


Assuntos
COVID-19/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , SARS-CoV-2 , Índice de Gravidade de Doença , Adolescente , COVID-19/patologia , Teste para COVID-19 , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Razão de Chances , Estudos Prospectivos , Fatores de Risco
17.
Food Sci Technol Int ; 27(6): 485-498, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34487460

RESUMO

The optimal conditions for elaborating oil/water nanoemulsions of lemongrass (LG), cinnamon bark (CB) and cinnamon leaves (CL) essential oils and their antimicrobial activity against Zygosaccharomyces bailii at pH 4.00 were studied. The effect of the emulsification methodology on the physical stability and antimicrobial activity of the nanoemulsions were also evaluated. Furthermore, the sensory impact of nanoemulsions added to an apple juice was tested. LG and CL nanoemulsions were elaborated by ultrasonication and CB nanoemulsion, by high-speed homogenization. They were stable for at least 120 days at 25 °C. They exhibited antimicrobial activity against Z. bailii being CB the most effective since it showed the smallest MIC value (156.3 mg/l), followed by LG (468.8 mg/l) and CL (1250.0 mg/l). A slight increase in growth rate was observed due to ultrasonication. An additive interaction in relation to the inhibitory effect between LG and CB nanoemulsions against Z. bailii was observed. While nanoemulsions obtained would be used as natural antimicrobial agents in food and beverage products, only LG nanoemulsion at MIC concentration diluted was acceptable in juice showing the sensory impact of essential oils on foods.


Assuntos
Cymbopogon , Óleos Voláteis , Zygosaccharomyces , Cinnamomum zeylanicum , Emulsões , Óleos Voláteis/farmacologia , Saccharomycetales
19.
Int J Biol Macromol ; 164: 1657-1664, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777415

RESUMO

This study evaluated the effect of some natural additives and the structure imparted by them on microbial growth and rheological characteristics in acidic model foods with reduced glycidic content. Systems were formulated using gellan gum, as gelling agent; xylitol, as aw depressor; and natamycin, as antimicrobial. Additive-free control systems were prepared. The pH was adjusted to 3.50 or 5.50 as required. Systems were inoculated with Zygosaccharomyces bailii. The effect of additives alone and combined on Z. bailii growth was studied. In some cases, the possible use of additives as yeast nutrients was evaluated. Furthermore, systems rheological characterization was performed. Additives and the structure given by gellan gum significantly affected yeast growth. Gellan gum initially slowed Z. bailii development, but as storage progressed, it acted as yeast carbon source, promoting its growth. A similar trend was observed when xylitol effect was studied. Natamycin inhibited yeast growth in all systems assayed. Additives modified the rheological characteristics of the gels and this effect depended on gellan gum concentration and pH. Obtained results emphasize the importance of considering the different effects that additives and their combinations can exert on the growth of deteriorating microorganisms and on the physical characteristics of gels.


Assuntos
Natamicina/farmacologia , Polissacarídeos Bacterianos/farmacologia , Saccharomycetales/efeitos dos fármacos , Açúcares/metabolismo , Xilitol/farmacologia , Antibacterianos/farmacologia , Microbiologia de Alimentos/métodos , Concentração de Íons de Hidrogênio , Modelos Biológicos , Reologia/métodos
20.
Food Sci Technol Int ; 25(7): 579-587, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31117823

RESUMO

The objective of this work was to evaluate the effects of different decontamination treatments on the quality of dehydrated thyme, coriander, and mustard. Treatments applied were: (i) ultraviolet radiation treatment irradiation; (ii) steam, (iii) steam-ultraviolet radiation treatment; (iv) humidification-ultraviolet radiation treatment, and (v) steam-humidification-ultraviolet radiation treatment. Their effectiveness to control indigenous aerobic mesophiles and yeasts and molds population was assessed by plate count. The effect of proposed treatments on total polyphenol contents and antioxidant activity was also evaluated. Furthermore, the effect of treatments on spices performance to prevent canola oil oxidation was also analyzed. The use of steam-ultraviolet radiation treatment in aqueous medium was the most effective for decontamination, reducing the aerobic mesophiles and yeasts and molds counts between 1.0 and 2.2 log CFU/g dry spice. This treatment decreased significantly the polyphenol content and the antioxidant capacity of the three spices analyzed. However, in the case of mustard, the residual antioxidant compounds were able to control canola oil oxidation more efficiently than butylated hydroxytoluene. Results suggest that the use of steam-ultraviolet radiation treatment in aqueous medium can be useful in food preservation processes.


Assuntos
Coriandrum/química , Descontaminação/métodos , Conservação de Alimentos/métodos , Qualidade dos Alimentos , Mostardeira/química , Thymus (Planta)/química , Antioxidantes/análise , Dessecação , Manipulação de Alimentos , Oxirredução , Polifenóis/análise , Óleo de Brassica napus , Especiarias/análise , Vapor , Raios Ultravioleta
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