Foam mat drying of Tommy Atkins mango: Effects of air temperature and concentrations of soy lecithin and carboxymethylcellulose on phenolic composition, mangiferin, and antioxidant capacity

In this study, foam mat drying was applied to Tommy Atkins mango. Using a multifactorial design, the effect of soy lecithin (L) and carboxymethylcellulose (CMC) used as foam stabilizers (0–1.50 g/100 g), as well as temperature (T) (53–87 °C), on phenolic content and antioxidant capacity of mango were eval- uated. Mango pulp contains antioxidant, such as mangiferin, that can be utilized in foods to enhance their functional properties. Our results indicated that L and T had negative effects (p < 0.05) on the phenolic content and antioxidant capacity, whereas CMC had a positive effect (p < 0.05). Increasing the total amount of phenolic compounds present in dried mango contributed to the higher antioxidant capacity after the drying process. This study concluded that a drying T of 80 °C, and a concentration of 0.30 g/100 g of CMC and L are optimal for increased retention of phenolic compounds and antioxidant capacity.Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)-E-26/111.710/201

Antioxidative effect of Arthrospira platensis biomass on the lipid oxidation

Introduction: Cyanobacteria are promising natural sources of antioxidants. Environmental conditions that influence synthesis of substances in cultures of cyanobacteria have been studied. Objective: This investigation aimed to evaluate the antioxidative effect of Arthrospira platensis biomass on the process of lipid oxidation in bulk oil and oil/water emulsion. Method: Arthrospira platensis growth potential for antioxidant production under different cultivation conditions using an experimental design. The antioxidative effect of the methanolic extracts and the biomass on preventing lipid oxidation was measured by peroxide value (PV). Results: The results showed that the growing conditions to obtain the biomass promoted change in the protective ability of different biomass extracts. Extracts obtained from the cultivated biomass grown under 150 μmol photons/m2s-1, 1.875 g.L-1 NaNO3; 13.5 g.L-1 NaHCO3 (assay14) and 50 μmol photons/m2s-1, 2.5 g.L-1 NaNO3; 18.0 g.L-1 NaHCO3 (standard)  showed the most antioxidative effect on preventing lipid oxidation, therefore used in the formulation of mayonnaise. The mayonnaise made with soybean oil and 0.5% biomass was preserved against lipid photodegradation during seven days of storage, but the peroxide value related to control varied from 2.9 to 3.1 mEqO2.Kg-1, with no significant difference in the preservation afforded by tert-butilhydroquinone, in the same period of storage. In mayonnaise made with sunflower oil, biomass, independent of concentration, was unable to protect the product against photooxidation. Conclusions: The results demonstrate the protective ability on preventing lipid oxidation of Arthrospira platensis biomass and its potential for use in food lipid-based of soybean oil.TÍTULO PT: Efeito antioxidante da biomassa de Arthrospira platensis sobre a oxidação lipídicaIntrodução: Cianobactérias são promissoras fontes naturais de antioxidantes. Condições ambientais que influenciam síntese de substâncias em cultivos de cianobactérias tem sido estudadas. Objetivo: O objetivo deste estudo foi avaliar o efeito antioxidante da biomassa de Arthrospira platensis no processo de oxidação lipídica do óleo e da emulsão óleo/água. Método: A produção de antioxidantes por Arthrospira platensis em função das condições de cultivo foi avaliada por meio de planejamento experimental. O efeito antioxidante dos extratos metanólicos e das biomassas foi avaliado através do índice de peróxidos. Resultados: Os resultados mostram que as condições de crescimento para se obter a biomassa promoveram mudança na capacidade protetora dos diferentes extratos da biomassa. Extratos obtidos a partir da biomassa cultivada sob 150 μmol fótons/m2s-1, 1,875 g.L-1 NaNO3; 13,5 g.L-1 NaHCO3 (ensaio 14) e 50 μmol fótons/m2s-1, 2,5 g.L-1 NaNO3; 18,0 g.L-1 NaHCO3 (padrão) mostraram maior efeito antioxidante contra a oxidação lipídica, portanto, utilizados para formulação da maionese. A maionese feita com óleo de soja e 0,5% de biomassa foi preservada da fotodegradação lipídica durante sete dias de armazenamento, mas o índice de peroxido em relação ao controle variou de 2,9 para 3,1 mEqO2.Kg-1, não havendo diferença significativa da preservação proporcionada pela terc-butil hidroquinona, no mesmo período de armazenamento. Na maionese feita com óleo de girassol, a biomassa, independentemente da concentração, não foi capaz de proteger o produto contra a foto-oxidação. Conclusões: Os resultados demonstram a capacidade protetora contra a oxidação lipídica da biomassa de Arthrospira platensis e seu potencial para uso em alimentos ricos em lipídeos à base de óleo de soja

Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure &lt;= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

Survival of Shiga toxin-producing Escherichia coli O157:H7 in Minas frescal cheese

Shiga toxin-producing Escherichia coli (STEC) O157:H7 strains (isolated by cattle’s faeces and a reference strain, EDL933), were inoculated into pasteurized milk (102 and 103 cells.mL–1) to prepare the Minas frescal cheese. As control was used uninfected milk. Physicochemical and microbiological analyses were performed to milk and elaborated cheese. The O157:H7 strains were quantified in the stages of cheese processing and during 0, 2, 4, 5, 7, 10 and 15 storage days at 8 °C onto Sorbitol MacConkey Agar supplemented with potassium tellurite and cefixime (CT-SMAC). O157:H7 was not present in the pasteurised milk prior to the artificial inoculation. At the end of the processing the cheese had 10 to 100 times more STEC O157:H7 than the initial inoculum. During the storage, the Minas frescal cheese exhibited the largest population increase on the 4th and 5th day when inoculated with 102 and 103 cells.mL–1, respectively. Additionally, viable cells were found up to the 10th and 15th day, according to the amount of initial inoculum. This number of cells is able to cause infection in humans, and therefore, Minas frescal cheese, even when stored under refrigeration, is a potential vehicle of disease caused by STEC O157:H7

Foam Mat Drying of Tommy Atkins Mango: Effects of Air Temperature and Concentrations of Soy Lecithin and Carboxymethylcellulose on Carotenoid Compounds and Colorimetric Parameters

Mango is an important tropical fruit and a source of bioactive compounds. In this work foam mat drying was used for Tommy Atkins mango pulp. The effects of concentration of the foam stabilizers soy lecithin (L) and carboxymethylcellulose (CMC) (0-1.50 g/100 g) and drying temperature (T) (53-87 °C) were evaluated on the retention of total carotenoid and color parameters using a multilevel factorial design. Carotenoids were determinate by high pressure liquid chromatography method (HPLC-DAD). Carotenoid analysis showed presence of 9-cis-, 13-cis-, 15-cis- and all-trans-violaxanthin, luteoxanthin and their derivatives, β-carotene and cis-β-carotene. Results of the statistical analysis showed no significant effect of variables studied (p > 0.05) on the total carotenoid and β-carotene showing that this preservation method is interesting for obtaining carotenoid compounds rich dried mango pulp, but L had effect (p < 0.05) on color parameters L* and hab. The obtained results indicated that the foam mat drying process was efficient for retention of carotenoids of the mango pulp.de Brasil (FAPERJ) -- 26/111.710/201

Biomass production by Arthrospira platensis under different culture conditions

In biotechnological processes, the culture media components are responsible for high costs and exert a strong influence on the cyanobacteria behavior. The objective of this study was to evaluate the Arthrospira platensis growth potential for biomass production under different cultivation conditions using an experimental design. Three factors that are important for cyanobacteria growth were evaluated: sodium bicarbonate (9 to 18 g/l), sodium nitrate (1.25 to 2.5 g/l), and irradiance (20 to 120 µmol photons/m2.s–1). The results showed that the concentration of NaNO3 in the A. platensis medium can be reduced, resulting in increased concentrations of biomass produced. There was a higher biomass production due to the increase in the concentration of NaHCO3 and irradiance, mainly when these two factors varied tending towards the highest values studied. The results demonstrate the potential to produce Arthrospira platensis with lower costs and effluent generation without affecting cultivation performance

Production of phycobiliproteins by Arthrospira platensis under different lightconditions for application in food products

There has been an increase in investment in research on new sources of natural pigments for food application. Some cyanobacteria can change the structures responsible for light harvesting and cellular processes according to the wavelength and light intensity. This phenomenon has been described as complementary chromatic adaptation. The present study aimed to investigate the growth of Arthrospira platensis using different light qualities, irradiance, and wavelength by evaluating the production of biomass, proteins, and phycobiliproteins. The occurrence of the chromatic adaptation phenomenon in this cyanobacterium was also investigated. The microorganism used in this study, A. platensis, was grown in a Zarrouk medium under three irradiance levels, 50, 100, and 150 μmol fotons.m–2.s–1 with illumination provided by white and green fluorescent lamps. The condition of 150 µmol fotons.m–2.s–1 white light was the one that promoted the highest biomass production of A. platensis cultures (2115.24 mg.L–1). There was no difference in the production of total protein and total phycobiliproteins under the studied conditions. It is likely that the large supply of nitrogen in the Zarrouk medium was sufficient for cell growth and maintenance, and it supplied the production of accessory pigments composed of protein. Finally, there was no evidence of the complementary chromatic adaptation phenomenon in A. platensis cultivated under green light. Moreover, this condition did not increase phycocyanin production