This study assessed the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare (OV) and Rosmarinus officinalis (RO) essential oils against bacteria associated to minimally processed vegetables using the determination of Fractional Inhibitory Concentration (FIC) index, kill-time assay in vegetal broth and application in vegetable matrices. Moreover, it was determined chemical composition of the essential oils and their effects alone and in mixture on sensory characteristics of minimally processed vegetables. Carvacrol (66.9 g/100 g) was the most prevalent compound in OV essential oil, while for RO was 1.8-cineole (32.2 g/100 g). OV and RO essential oil showed MIC in a range of 1.25-5 and 20-40 μL/mL, respectively. FIC indices of the combined application of the essential oils were 0.5 against Listeria monocytogenes, Yersinia enterocolitica and Aeromonas hydrophilla suggesting a synergic interaction. Only for Pseudomonas fluorescens FIC index was 0.75 purposing additive effect. Application of the essential oils alone (MIC) or in mixture (¼ MIC + ¼ MIC or ¼ MIC + ½ MIC) in vegetable broth caused significant decrease (p b 0.05) in bacterial count over 24 h. Mixture of essential oils reduced (p b 0.05) the inocula of all bacteria in vegetable broth and in experimentally inoculated fresh-cut vegetables. Similar efficacy was found to reduce the autochthonous microflora in vegetables. Sensory evaluation of vegetables sanitized with essential oils revealed that the scores of the most evaluated attributes fell between like slightly and neither like nor dislike. The combination of essential oils at sub-inhibitory concentrations could mean an interesting approach to sanitize minimally processed vegetables.

No abstract

No abstract

Formulou-se receita básica de barra de cereal, empregando biscoito de amido de milho, açúcar demerara, leite em pó desnatado, flocos de arroz, aveia em flocos, xarope de glicose de milho, uva passa e damasco seco, como alternativa às barras encontradas no comércio. Para avaliar a composição centesimal e a aceitação desse produto caseiro foram utilizadas duas barras comerciais como parâmetro de referência. O produto foi submetido à determinações de carboidratos, lipídios, proteínas, fibras e à análise sensorial. Os resultados obtidos demonstraram que a barra formulada apresentou valores bem próximos aos das industrializadas no que se refere ao aporte calórico, carboidratos e proteínas. Entretanto, foram encontrados teores de lipídios 83,0% a 95,7% mais baixos que os das barras comerciais. O teor de fibras mostrou-se 14% menor na barra caseira, sugerindo-se a substituição do biscoito pela versão integral e inserção de cereais integrais na formulação para incrementar o aporte de fibras. A barra formulada obteve aceitação global superior à das barras de referência, representando opção para suplementação de fibras na dieta. Concluiu-se que o produto atende às especificações sanitárias, nutricionais e sensoriais. PALAVRAS-CHAVE: BARRA DE CEREAIS; FIBRA ALIMENTAR; ANÁLISE SENSORIAL.

This study aimed to evaluate the antibacterial activities of the essential oils from Origanum vulgare L. and Rosmarinus officinalis L., both singly and in combination at subinhibitory concentrations against Listeria monocytogenes, and to investigate the possible mechanisms underlying these activities. Used singly or in a mixture, the essential oils led to a significant decrease in cell viability during 24 h of exposure. Decreased glucose consumption and the loss of cellular material by L. monocytogenes were found immediately after addition of the essential oils alone and in combination, and continued for up to 360 min. Analysis of cells exposed to the essential oils using electron microscopy revealed drastic ultrastructural changes occurring over time, including the changes in cell wall structure, rupture of plasma membranes, shrinking of the cytoplasmic content and leakage of intracellular material. O. vulgare L. and R. officinalis L. essential oils combined at subinhibitory concentrations could be rationally applied to inhibit the growth of L. monocytogenes in food products. PRACTICAL APPLICATIONS L. monocytogenes is a foodborne pathogen of particular concern in ready‐to‐eat products, such as minimally processed vegetables, because of its ability to survive and grow at refrigeration temperatures. The special risk posed by L. monocytogenes for the consumption of minimally processed vegetables has led to investigations on the development of novel technologies to control this contamination. In this context, plant essential oils have received particular interest for their potential to control L. monocytogenes in these foods. The findings of our study clearly indicate that the essential oil of oregano and rosemary, singly or in combination at subinhibitory concentrations, caused critical damages in L. monocytogenes cells. These essential oils combined at subinhibitory concentrations could be rationally applied to control the survival of L. monocytogenes in foods.

This study investigated the effects of the essential oils from Origanum vulgare L. (oregano [OVEO]) and Rosmarinus officinalis L. (rosemary [ROEO]) on the membrane permeability, morphology and cell viability of Pseudomonas fluorescens ATCC 11253 in a vegetable-based broth after treatment with one essential oil (OVEO: 5 mL/mL; ROEO: 40 mL/mL) and with a combination of both essential oils (OVEO: 1.25 mL/mL + ROEO: 20 mL/mL). Release of cell material was observed immediately after the addition of the essential oils, both singly and as a mixture, in the growth media. Electron microscopy of bacterial cells exposed to OVEO, ROEO and the mixture of both revealed the following morphological changes after 2 and 3 h of exposure: alteration in the cell wall structure, rupture of the plasma membrane, shrinking of the cells, condensation of the cytoplasmic content and leakage of the intracellular material. Confocal scanning laser microscopy revealed increased cell membrane permeability, which resulted in cell death after short exposure times of 15 and 30 min. A combination of sublethal amounts of OVEO and ROEO could be applied to inhibit the growth of P. fluorescens in vegetables. PRACTICAL APPLICATIONSPseudomonas fluorescens is of particular concern in vegetable products, such as minimally processed vegetables, because of its ability to survive and grow at cold environments. The special risk posed by P. fluorescens on the storage and consumption of fresh vegetables has provoked studies on development of novel technologies to control this contamination. In this context, plant essential oils have received particular interest for their potential to control this bacterium in these foods. The findings of our study clearly indicate that the essential oil of Origanum vulgare and Rosmarinus officinalis, singly or in combination at sublethal amounts, caused a decrease in cell viability, loss of cellular material and drastic ultrastructural changes in P. fluorescens. These essential oils combined at subinhibitory concentrations could be rationally applied to control the survival of P. fluorescens in fresh vegetables and give the balance of microbial safety and organoleptic acceptability.

In recent years the incorporation of probiotic bacteria intake and weight gain among mice fed the Z. mobilis in into foods has received increasing scientific interest for comparison to the control group. No bacteria were health promotion and disease prevention. The safety found in blood, liver and spleen of any animals. Mice and probiotic properties of Zymomonas mobilis CP4 receiving Z. mobilis showed significantly differences (p < (UFPEDA-202) was studied in a Wistar rat model fed 0.05) in total and differential leucocytes count, excepting the 10 9 colony forming units (cfu)/mL -1 of the assayed for neutrophils, after the experimental period. strain for 30 days. No abnormal clinical signs were Otherwise, it was not found in control group. noted in the group receiving viable cells of Z. mobilis Histological examination showed that feeding mice with and water (control) during the period of the experiment.Z. mobilis caused no signs of adverse effects on gut, liver There were no significant difference (p > 0.05) in feed and spleen. From these results, Z. mobilis CP4

The pitanga (Eugenia uniflora L.) is a fruit with a characteristic flavor, that has a variant coloration from orange to intense purple. It is referred to as a source of several nutrients, which give them interesting nutritional and biological properties, often able to act as protective factors for various pathologies. However, the variation of these nutrients depends on the variety of the plant, conditions of production and maturation. Thus, the present study aimed to characterize the nutritional composition and the content of pigments present in the pulps and seeds of pitanga in the purple and red varieties, grown in the region of the Paraíba swamp. The fruits were selected at maturity stages 5 for red and 6 for purple, cleaned and dried by lyophilization, with the seeds being separated from the pulps for physical-chemical analysis. According to the results obtained, it was observed that among the pulps, there was a significant difference regarding the parameters of moisture, water activity and protein and carbohydrate content, the highest values of which were for the red variety. In the seeds,