Enzyme activities and pectin breakdown of sapodilla submitted to 1-methylcyclopropene

O objetivo deste trabalho foi investigar a influência do 1-metilciclopropeno (1-MCP) nas atividades das enzimas hidrolíticas da parede celular e nas mudanças na degradação da pectina durante o amadurecimento de sapoti (Manilkara zapota cv. Itapirema 31). Frutos de sapotizeiro foram tratados com o inibidor da ação do etileno, 1-MCP, na concentração de 300 nL L-1, por 12 horas e armazenados sob atmosfera modificada, à temperatura de 25±2ºC, por 23 dias. A firmeza, conteúdo de pectina total e solúvel e enzimas da parede celular foram avaliados durante todo o período de armazenamento. O 1-MCP a 300 nL L-1 por 12 horas retardou significativamente o amolecimento de sapoti por 11 dias a 25ºC. O tratamento com 1-MCP afetou a atividade das enzimas pectinametilesterase e poligalacturonase e inibiu o aumento da atividade beta-galactosidase por 8 dias, e, conseqüentemente, resultou em menor solubilização das substâncias pécticas. A beta-galactosidase parece ser relevante no amolecimento de sapoti e responsável pela modificação das pectinas e das xiloglucanas ligadas as microfibrilas de celulose.The objective of this work was to investigate the influence of 1-methylcyclopropene (1-MCP) at 300 nL L-1 on activities of cell wall hidrolytic enzymes and pectin breakdown changes which Sapodilla (Manilkara zapota cv. Itapirema 31) cell wall undergoes during ripening. Sapodilla were treated with ethylene antagonist 1-MCP at 300 nL L-1 for 12 hours and then, stored under a modified atmosphere at 25ºC for 23 days. Firmness, total and soluble pectin and cell wall enzymes were monitored during storage. 1-MCP at 300 nL L-1 for 12 hours delayed significantly softening of sapodilla for 11 days at 25ºC. 1-MCP postharvest treatment affected the activities of cell wall degrading enzymes pectinmethylesterase and polygalacturonase and completely suppressed increases in beta-galactosidase for 8 days, resulting in less pectin solubilization. Beta-galactosidase seems relevant to softening of sapodilla and is probably responsible for modification of both pectin and xyloglucan-cellulose microfibril network

Influência do tratamento pré-colheita com 1-aminoetoxivinilglicina e ácido giberélico na fisiologia e na qualidade de pedúnculos de caju

The objective of this work was to evaluate the effects of the preharvest treatment with gibberellic acid (GA3) and aminoethoxyvinylglycine (AVG) on the quality and physiological attributes of ripe 'CCP 76' cashew (Anacardium occidentale) peduncles at different developmental stages. Sprays of 180 mg L-1 GA3 and 180 mg L-1 AVG were applied, combined and isolated, at 34, 40, and 44 days after anthesis (DAA), and peduncles were harvested ripe at 46 DAA and evaluated for physical and physiological variables. The treatment with GA3 resulted in firmer peduncles with a greater apical diameter, but did not affect the physiological variables activity of the pectin methylesterase and polygalacturonase cell wall enzymes and degree of lipid peroxidation of the biological membranes, nor the physical attributes total mass (peduncles and nut) and nut size. At early developmental stages (34 DAA), GA3 increased the activity of the antioxidant enzymes superoxide dismutase and catalase, and, at later stages (40 DAA), promoted polyphenol and carotenoid accumulation. The application of AVG at the final stages (44 DAA) provided greater total antioxidant activity, despite the lower ascorbate peroxidase activity. The application of GA3 pre-harvest increases the firmness and diameter of the cashew peduncles, and the treatment with AVG increases the total antioxidant activity of the peduncles.O objetivo deste trabalho foi avaliar o efeito do tratamento pré-colheita com ácido giberélico (GA3) e 1-aminoetoxivinilglicina (AVG) nos atributos de qualidade e fisiológicos de pedúnculos maduros de cajueiro (Anacardium occidentale) 'CCP 76', em diferentes estádios de desenvolvimento. Foram realizadas pulverizações com 180 mg L-1 GA3 e 180 mg L-1 AVG, combinadas e isoladas, aos 34, 40 e 44 dias após a antese (DAA), e os pedúnculos foram colhidos maduros aos 46 DAA para avaliações de variáveis físicas e fisiológicas. O tratamento com GA3 proporcionou pedúnculos mais firmes e com maior diâmetro apical, mas não influenciou as variáveis fisiológicas atividades das enzimas pectinametilesterase e poligalacturonase da parede celular e grau de peroxidação lipídica das membranas biológicas, nem os atributos físicos massa total (pedúnculo e castanha) e comprimento e largura da castanha. Em estádios iniciais (34 DAA), GA3 aumentou a atividade das enzimas antioxidantes superóxido dismutase e catalase, e, nos finais (40 DAA), promoveu o acúmulo de polifenóis e carotenoides. A aplicação de AVG, ao final do desenvolvimento (44 DAA), proporcionou maior atividade antioxidante, apesar da menor atividade da ascorbato peroxidase. A aplicação de GA3 em pré-colheita promove aumento da firmeza e do diâmetro dos pedúnculos de cajueiro, e o tratamento com AVG aumenta a atividade antioxidante dos pedúnculos

Assessment of risk scores to predict mortality of COVID-19 patients admitted to the intensive care unit

ObjectivesTo assess the ABC2-SPH score in predicting COVID-19 in-hospital mortality, during intensive care unit (ICU) admission, and to compare its performance with other scores (SOFA, SAPS-3, NEWS2, 4C Mortality Score, SOARS, CURB-65, modified CHA2DS2-VASc, and a novel severity score).Materials and methodsConsecutive patients (≥ 18 years) with laboratory-confirmed COVID-19 admitted to ICUs of 25 hospitals, located in 17 Brazilian cities, from October 2020 to March 2022, were included. Overall performance of the scores was evaluated using the Brier score. ABC2-SPH was used as the reference score, and comparisons between ABC2-SPH and the other scores were performed by using the Bonferroni method of correction. The primary outcome was in-hospital mortality.ResultsABC2-SPH had an area under the curve of 0.716 (95% CI 0.693–0.738), significantly higher than CURB-65, SOFA, NEWS2, SOARS, and modified CHA2DS2-VASc scores. There was no statistically significant difference between ABC2-SPH and SAPS-3, 4C Mortality Score, and the novel severity score.ConclusionABC2-SPH was superior to other risk scores, but it still did not demonstrate an excellent predictive ability for mortality in critically ill COVID-19 patients. Our results indicate the need to develop a new score, for this subset of patients

Antioxidant compoundsand total antioxidant activity in fruits of acerola from cv. Flor Branca, Florida Sweet and BRS 366

Information on antioxidant properties at different ontological stages may help producers and food technologists to identify which cultivar and/or maturity stage are most adequate for their need, therefore this work aimed to study the changes in the antioxidant metabolism during acerola development. Fruit from cv. Flor Branca, BRS366 and Florida Sweet were harvested at different stages: immature green colored (I), physiologically mature with green color and maximum size (II), breaker (III) and full red ripe (IV). After harvest, fruits were selected, divided into four replications with 500 g each and evaluated regarding their titratable acidity, pH, soluble solids, total soluble sugar, vitamin C, polyphenol, anthocyanin, yellow flavonoid, total antioxidant activity and antioxidant enzyme activity. Anthocyanin and flavonoid were determined through LC-DAD-ESI/MS and all analysis followed a completely randomized factorial 3 x 4 design. Fruits of 'Florida Sweet' presented significantly higher soluble solids (9.46ºBrix). Vitamin C content decreased during ripening, but ripe 'BRS 366' fruits showed the greatest values (1363 mg.100 g-1) and highest TAA with 42.36 µM TEAC.g-1FW. Cyanidin 3-rhamnoside (520.76 mg.100 g-1 DM) and quercetin 3-rhamnoside (33.72 mg.100 g-1 DM) were the most abundant anthocyanin and yellow flavonoids found mainly in 'Flor Branca' fruit of acerola, whose antioxidant enzymes activities were also higher. Ripe 'Florida Sweet' fruit presents a great potential for fresh consumption, meanwhile physiologically mature 'BRS 366' fruit seems the best option for the bioactive compounds processing industry. As 'Flor Branca' fruit of acerola kept the highest activity levels, it could be an indicative of greater potential for postharvest conservation

QUALITY OF ACEROLA (Malpighia emarginata) TREATED WITH GIBBERELIC ACID AND STORED UNDER REFRIGERATION

<div><p>ABSTRACT The goal of this study was study the postharvest quality of acerola clone BRS 236 (Malpighia emarginata D.C.) which was harvested at physiological maturity and submitted to four treatments under immersion during 5 minutes at 25 °C, which are: control (water), 60 mg L-1; 120 mg L-1 and 180 mg L-1. After treatment the fruits were packed in polystyrene trays and placed with polyethylene film and then stored at 10 ± 2 °C and 85 ± 5% RH for 12 days. Were analyzed in three days intervals (0, 3, 6, 9 and 12 days): skin color, firmness, pH, titratable acidity, soluble solids, SS/TA ratio, vitamin C and yellow flavonoids. Vitamin C, anthocyanins and yellow flavonoids were not influenced by treatments with GA3 at the end of 12-day of cold storage at 10 ºC. The exogenous application of 120 mg L-1 of GA3 resulted in retention of red color and content of anthocyanins of acerola fruits BRS 236 clone 12-day storage at 10 °C.</p></div

Effect of xyloglucan-based coating enriched with cashew apple coproduct extract on quality and antioxidant metabolism of guava during ripening postharvest

This study evaluated the postharvest quality and antioxidant metabolism of ‘Paluma’ guavas treated with a xyloglucan-based coating containing an antioxidant extract from cashew apple coproduct (1%, v/v) (XCE) during ripening for 14 days at 25 °C. It was observed that XCE promoted lower levels of lipid peroxidation of cell membranes and lower activity of wall hydrolytic enzymes (polygalacturonase and pectinmethylesterase), thus a better maintenance of firmness during ripening. It was also observed that XCE increased the antioxidant potential because of the higher ascorbic acid and polyphenols content and the higher activity of antioxidant enzymes. Thus, XCE is a postharvest technology that not only improves the quality of ‘Paluma’ guavas, but also delays the oxidative ripening processes by increasing the antioxidant defense system of the fruit

Enzyme activities and pectin breakdown of sapodilla submitted to 1-methylcyclopropene Atividade de enzimas e degradação de pectinas de sapoti submetido ao 1-metilciclopropeno

The objective of this work was to investigate the influence of 1-methylcyclopropene (1-MCP) at 300 nL L-1 on activities of cell wall hidrolytic enzymes and pectin breakdown changes which Sapodilla (Manilkara zapota cv. Itapirema 31) cell wall undergoes during ripening. Sapodilla were treated with ethylene antagonist 1-MCP at 300 nL L-1 for 12 hours and then, stored under a modified atmosphere at 25º C for 23 days. Firmness, total and soluble pectin and cell wall enzymes were monitored during storage. 1-MCP at 300 nL L-1 for 12 hours delayed significantly softening of sapodilla for 11 days at 25º C. 1-MCP postharvest treatment affected the activities of cell wall degrading enzymes pectinmethylesterase and polygalacturonase and completely suppressed increases in beta-galactosidase for 8 days, resulting in less pectin solubilization. Beta-galactosidase seems relevant to softening of sapodilla and is probably responsible for modification of both pectin and xyloglucan-cellulose microfibril network.O objetivo deste trabalho foi investigar a influência do 1-metilciclopropeno (1-MCP) nas atividades das enzimas hidrolíticas da parede celular e nas mudanças na degradação da pectina durante o amadurecimento de sapoti (Manilkara zapota cv. Itapirema 31). Frutos de sapotizeiro foram tratados com o inibidor da ação do etileno, 1-MCP, na concentração de 300 nL L-1, por 12 horas e armazenados sob atmosfera modificada, à temperatura de 25± 2º C, por 23 dias. A firmeza, conteúdo de pectina total e solúvel e enzimas da parede celular foram avaliados durante todo o período de armazenamento. O 1-MCP a 300 nL L-1 por 12 horas retardou significativamente o amolecimento de sapoti por 11 dias a 25º C. O tratamento com 1-MCP afetou a atividade das enzimas pectinametilesterase e poligalacturonase e inibiu o aumento da atividade beta-galactosidase por 8 dias, e, conseqüentemente, resultou em menor solubilização das substâncias pécticas. A beta-galactosidase parece ser relevante no amolecimento de sapoti e responsável pela modificação das pectinas e das xiloglucanas ligadas as microfibrilas de celulose