University of Lleida

About: University of Lleida is a education organization based out in Lleida, Spain. It is known for research contribution in the topics: Population & Pregnancy. The organization has 2939 authors who have published 5853 publications receiving 148417 citations. The organization is also known as: Escola Superior Politècnica & Universitat de Lleida.

Partition of phenolic compounds during the virgin olive oil industrial extraction process

Abstract: Phenolics have been considered an important group of natural antioxidants. The type and quantity of phenolics vary in olive matrices (leaves, fruit, stones, seeds, and paste). However, the relationships linking the products from the olive oil extraction process are poorly studied. This manuscript deals with the partition of phenolic compounds during olive oil production season at three times. Samples were taken during malaxation to determine the phenolic content in the olive paste at 0, 15, and 45 min. The wet pomace and oil phases were analyzed and the phenolics quantified in terms of kilogram of olive paste. Malaxation time had an important effect on the alcohols and secoiridoids. Hydroxytyrosol and tyrosol decreased, and their hydrophilic character was proved through their presence in the wet pomace and wastewater. Oleuropein and ligstroside degradation results in the formation of secoiridoid derivatives, mainly the dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA). A molar transfer index (MTI) was established between the 3,4-DHPEA-EDA in the olive paste and olive oil (as the liquid phase) and wet pomace (as the solid phase). An increasing trend was observed for the molar transference to virgin olive oil with the advance of the crop season.

Forty percent methionine restriction lowers DNA methylation, complex I ROS generation, and oxidative damage to mtDNA and mitochondrial proteins in rat heart.

Abstract: Methionine dietary restriction (MetR), like dietary restriction (DR), increases rodent maximum longevity. However, the mechanism responsible for the retardation of aging with MetR is still not entirely known. As DR decreases oxidative damage and mitochondrial free radical production, it is plausible to hypothesize that a decrease in oxidative stress is the mechanism for longevity extension with MetR. In the present investigation male Wistar rats were subjected to isocaloric 40% MetR during 7 weeks. It was found that 40% MetR decreases heart mitochondrial ROS production at complex I during forward electron flow, lowers oxidative damage to mitochondrial DNA and proteins, and decreases the degree of methylation of genomic DNA. No significant changes occurred for mitochondrial oxygen consumption, the amounts of the four respiratory complexes (I to IV), and the mitochondrial protein apoptosis-inducing factor (AIF). These results indicate that methionine can be the dietary factor responsible for the decrease in mitochondrial ROS generation and oxidative stress, and likely for part of the increase in longevity, that takes place during DR. They also highlight some of the mechanisms involved in the generation of these beneficial effects.

Patterns of topographic change in sub-humid badlands determined by high resolution multi-temporal topographic surveys

Abstract: Badlands are highly erodible landscapes with sparse vegetation and rapid runoff responses. Badland surfaces experience high erosion rates that may have a direct and marked influence on river channel networks and catchment scale sediment budgets. Erosion rates from badlands have been widely estimated by discrete observations of topographic change measured by erosion pins or profile meters. Recent developments in survey instrumentation provide the opportunity to build high-resolution topographic models over multiple spatial scales at sub-centimeter accuracy. In this paper we demonstrate how reliable estimates of topographic variables and temporal change can be derived for badlands by repeat Terrestrial Laser Scanning (TLS) surveys undertaken at multiple temporal (event to annual) scales. A total of seven TLS-surveys were obtained in an experimental sub-humid badland located in the Central Pyrenees. Data analyses were conducted on two temporal scales: (a) five rainfall events and (b) three long term (spaced over an annual cycle) scales. Our results show a clear erosional pattern for most of the badland at the annual scale (i.e. annual net change at around − 6 cm yr − 1 ). Aspect, surface roughness and slope were significant predictors of topographic change, although the sign and magnitude of the change differed at the event scale. Net topographic change at the event scale varied from − 1.8 to 1.4 cm. Although these patterns could be also affected by swell-shrink processes, surface roughness was more important at controlling badland geomorphological processes at the event-scale than the annual scale. Our observations suggest that longer-term studies may underestimate the importance of surface roughness as a control on badland geomorphology. At the annual scale the effect of aspect in the sign of the topographic change was removed and slope becomes more important. Erosion proved to be dominant on slopes higher than 100%. Overall, the results indicate that coupling of appropriately-scaled spatial and temporal data is critical to understand topographic changes and their drivers on badlands. Although the approach outlined in this paper was only applied to a relatively small area, with careful survey design and application of new survey technology, it could readily be upscaled to cover entire badland systems. Such surveys would permit detailed analysis of controls of sedimentological connectivity across badlands and their influence on channel networks and catchment sediment budgets.