It had as objective to evaluate the effect of 8-hydroxyquinoline and chlorine, isolated and mixed in and conservation of the stem stick of the emperor. Twenty of the stem torch ginger (Etlingera elatior), variety Red Torch were harvested, transported, and immersed in standardized solutions containing biocides for 48 hours. The biocide used were 100 mg L -1 of chlorine; 250 mg L -1 of 8-(HQC); 500 mg L -1 of 8-(HQC) and 50 mg L -1 of chlorine + 50 mg L -1 of 8-(HQC), the control corresponded to water. The stems stay immersed in water for nine days at 20 ± 4 ºC. Every 24 hours, the water in the container was replaced. During nine days, some measurements were realized of pH of the water in which the stems stay immersed, in the same way, it was measured the consumption/loss volume of the water for each 24 hours in the containers. The stems were weighed and also samples were taken from the base of the stems and pear ligule determination of peroxidase activity. In general, the use of solutions of 8-(HQC), 250 and 500 mg L -1 , make easier the flux of water in the vases, measured by the consumption of water; provided lower peroxidase activity at the base, independent of the pH of the solution and maintained lower peroxidase activities in the ligule. Thus, with the results obtained, it demonstrated promise the use of 8-(HQC), in the highest concentrations tested (250 and 500 mg L -1 ) for quality maintenance of cut stems of Etlingera elatior, variety Red Torch.
Enzyme assays are based on methodologies described in the literature. However, the enzyme kinetics must be adjusted to obtain more reliable results. This study aimed to adjust assays by testing different polyphenol oxidase (PPO) and peroxidase (POD) extract amounts and reaction times in sweet potato cultivars harvested at different times. Sweet potato cultivars Paraná, Mãe de Família, and ESAM1 were harvested at 120, 150, and 180 days after planting and minimally processed. A 0.25 g sample was used to determine PPO and POD activities immediately after minimal processing at each harvest. Extraction was performed in 1500 μL phosphate buffer (0.2 M, pH 6.0). The PPO assay was performed by adding 10-50 μL extract, 1490-1450 μL phosphate buffer (0.2 M, pH 6.0), and 1500 μL catechol (0.2 M). The POD assay was carried out by adding 10-50 μL extract to a reaction medium containing 1790-1750 μL phosphate buffer (0.2 M, pH 6), 100 μl guaiacol (5 g L-1), and 100 μL hydrogen peroxide (0.8 g L-1). In both cases, the evaluated reaction times were 1, 2, and 3 min. In the three cultivars, PPO and POD activities increased with the volume of extract and reaction time at all harvest times. The enzyme extract volume of 10 μL for 2 min promoted a continuous increase in PPO and POD enzyme activities in all studied cultivars and at all reaction times.
BACKGROUND: The present study investigated the sensory acceptance, oxidative damage and protection, and possible anatomical-structural damage of cells from the surface of shapes of minimally processed yam. The tubers were minimally processed into the peeled rondelle, dice and 'chateau cut' (chateau) shapes, the latter of which was obtained after performing the abrasion technique. Control treatment corresponded to the rondelle shape with the periderm. The pieces were kept packed at 5 ± 2 °C for 14 days.RESULTS: Peeled rondelle and chateau were sensorially the most well-accepted yam shapes and achieved the highest purchase intention. The enzymes were partially modulated by the detected H 2 O 2 levels. Oxidative burst lasted longer in the minimally processed tissues than in the control. Polyphenol oxidase activity showed a clear difference in behavior between the minimally processed pieces and the control. Minimal processing induced transient increases in phenolic compounds, for which the expression was lowest in the abraded pieces. On the other hand, these pieces exhibited greater cell collapse on the surface of the amyliferous parenchyma.CONCLUSION: Based on the results of the trained panel, the abrasion technique is an alternative to provide shapes that are better accepted and marketable, more resistant to browning, and can be stored for up to 12 days. Resistance to browning may be related to a more efficient modulation of enzymatic antioxidant systems and intense deposition of cell debris on the surface of the amyliferous parenchyma.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.