Conversion of levulinic acid to gamma-valerolactone over Zr-containing metal-organic frameworks: Evidencing the role of Lewis and Bronsted acid sites

[EN] Zr-containing UiO-66 and MOF-808 are evaluated for converting levulinic acid (LA) into gamma-valerolactone (GVL) through various routes: (i) Step-wise esterification of LA to n-butyl levulinate (nBuL) and Meerwein-PonndorfVerley (MPV) reduction to GVL; (ii) One-pot two-steps esterification with n-butanol followed by MPV reduction with sec-butanol; and (iii) direct conversion of LA into GVL through a tandem reaction. Selection of this multistep complex reaction evidences the participation of the different acid sites (Lewis or Bronsted) of the material in each individual step: Bronsted-induced acid sites catalyze esterification reaction efficiently, while Lewis acid sites are the preferred sites for the MPV step. Sulfation of MOF-808 is used to enhance the Bronsted acidity of MOF-808, which improves the performance for esterification. However, the sulfate groups introduced are detrimental for the MPV step, since they reduce the intra-pore space available to form the required bulky transition state. These results evidence the need to find the best equilibrium between Bronsted and Lewis acid sites to optimize the outcome of this multistep reaction.Financial support by the Spanish Government is acknowledged through projects MAT2017-82288-C2-1-P and the Severo Ochoa program (SEV-2016-0683). Aula-CEMEX is also acknowledged for a fellowship to JMG.Guarinos, J.; Cirujano, F.; Rapeyko, A.; Llabrés I Xamena, FX. (2021). Conversion of levulinic acid to gamma-valerolactone over Zr-containing metal-organic frameworks: Evidencing the role of Lewis and Bronsted acid sites. Molecular Catalysis. 515:1-11. https://doi.org/10.1016/j.mcat.2021.111925S11151

The impact of type of dietary protein, animal versus vegetable, in modifying cardiometabolic risk factors: A position paper from the International Lipid Expert Panel (ILEP)

Proteins play a crucial role in metabolism, in maintaining fluid and acid-base balance and antibody synthesis. Dietary proteins are important nutrients and are classified into: 1) animal proteins (meat, fish, poultry, eggs and dairy), and, 2) plant proteins (legumes, nuts and soy). Dietary modification is one of the most important lifestyle changes that has been shown to significantly decrease the risk of cardiovascular (CV) disease (CVD) by attenuating related risk factors. The CVD burden is reduced by optimum diet through replacement of unprocessed meat with low saturated fat, animal proteins and plant proteins. In view of the available evidence, it has become acceptable to emphasize the role of optimum nutrition to maintain arterial and CV health. Such healthy diets are thought to increase satiety, facilitate weight loss, and improve CV risk. Different studies have compared the benefits of omnivorous and vegetarian diets. Animal protein related risk has been suggested to be greater with red or processed meat over and above poultry, fish and nuts, which carry a lower risk for CVD. In contrast, others have shown no association of red meat intake with CVD. The aim of this expert opinion recommendation was to elucidate the different impact of animal vs vegetable protein on modifying cardiometabolic risk factors. Many observational and interventional studies confirmed that increasing protein intake, especially plant-based proteins and certain animal-based proteins (poultry, fish, unprocessed red meat low in saturated fats and low-fat dairy products) have a positive effect in modifying cardiometabolic risk factors. Red meat intake correlates with increased CVD risk, mainly because of its non-protein ingredients (saturated fats). However, the way red meat is cooked and preserved matters. Thus, it is recommended to substitute red meat with poultry or fish in order to lower CVD risk. Specific amino acids have favourable results in modifying major risk factors for CVD, such as hypertension. Apart from meat, other animal-source proteins, like those found in dairy products (especially whey protein) are inversely correlated to hypertension, obesity and insulin resistance

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset