Influence of Biodegradable Release Oils on the Physical and Mechanical Properties of Light-Colored Architectural Concrete

In the article, unique formulations of biodegradable, non-toxic, edible oil-based release oils were developed and tested on architectural concrete. The produced agents have physicochemical properties similar to diesel fuel, but at the same time, are renewable and biodegradable products. An ultrasound was used to properly combine the liquid phase of edible oil and the liquid phase of glyceryl trioleate and/or water. Based on the PN-B-19305 standard, seven-component configurations were designed and then tested. The wettability of the concrete was determined by contact angle (CA) analysis. After the application of the formulations produced, the architectural concrete still had good wettability. The vapor permeability test showed that the tested release agents did not inhibit water vapor diffusion from the tested samples. The O65G35 (65% unique edible oil formula and 35% glyceryl trioleate) concrete had the best absorption. In this case, the CA was 56° after oil application and 46° before. The new agents did not impair the adhesion of the plaster to concrete. The O90W10 concrete showed the best adhesion of plasters made with it—51.9 kN/m2. The study also showed that the concrete surface had excellent paint absorption despite the use of release agents. The architectural concrete was evenly covered with paint without any problem. There were no difficulties in applying it, e.g., greasy places preventing the concrete from being coated with emulsion. The suitability of the produced release oils for lightweight architectural concrete structures intended for facades was confirmed. The best results were obtained after using formulations O65T35 and O90W10.

Selective production of mono-aromatics from lignocellulose over Pd/C catalyst: the influence of acid co-catalysts

The ‘lignin-first’ approach has recently gained attention as an alternative whole biomass pretreatment technology with improved yield and selectivity of aromatics compared with traditional upgrading processes using technical lignins. Metal triflates are effective co-catalysts that considerably speed up the removal of lignin fragments from the whole biomass. As their cost is too high in a scaled-up process, we explored here the use of HCl, H2SO4, H3PO4 and CH3COOH as alternative acid co-catalysts for the tandem reductive fractionation process. HCl and H2SO4 were found to show superior catalytic performance over H3PO4 and CH3COOH in model compound studies that simulate lignin–carbohydrate linkages (phenyl glycoside, glyceryl trioleate) and lignin intralinkages (guaiacylglycerol-β-guaiacyl ether). HCl is a promising alternative to the metal triflates as a co-catalyst in the reductive fraction of woody biomass. Al(OTf)3 and HCl, respectively, afforded 46 wt% and 44 wt% lignin monomers from oak wood sawdust in tandem catalytic systems with Pd/C at 180 °C in 2 h. The retention of cellulose in the solid residue was similar.

Chylomicron remnant uptake by enterocytes is receptor dependent

During glyceryl trioleate absorption in the rat, mucosal triacylglycerol (TG) fatty acids have been shown to consist of only 71% exogenous oleate. Chylomicron remnants are enriched with endogenous TG fatty acids, compared with their parent chylomicrons, which consist primarily of exogenous TG fatty acids. Because enterocytes have the apolipoprotein B-100/E receptor, this study was directed at determining whether the cells can take up and metabolize chylomicron remnants and, if so, whether this was receptor mediated. Isolated enterocytes were incubated with purified 3H-labeled chylomicron remnants. The remnants were shown to be taken up by the basolateral membrane, not the apical membrane. Remnant uptake was proportional to time and number of enterocytes, and saturation kinetics were observed. Nonradiolabeled remnants, human low-density lipoprotein (LDL), anti-LDL receptor antibody, and receptor-associated protein, an LDL-related receptor inhibitor, were all shown to compete for or reduce 3H-remnant uptake. Remnants taken up by the enterocytes could not be removed on incubation with excess human LDL. Uptake was shown to be greatest in the villus tips of the proximal intestine. These studies suggest that enterocytes take up chylomicron remnants by a receptor-mediated process from their basolateral membranes and that the remnants could provide a source of endogenous TG fatty acids for the enterocytes.

Role of the intestine in chylomicron remnant clearance

When 810 mumol of [3H]glyceryl trioleate (TO) were infused intraduodenally over 6 h into rats, 29% of the triacylglycerol (TG) acyl groups in the mucosa were not from the infusate. We tested the hypothesis that chylomicron remnants contribute to the mucosal pool of nondietary TG acyl groups, since the acyl group composition of the chylomicron remnants was 58% oleate, compared with 90% in their parent chylomicrons. Purified 3H-labeled remnants were generated from chylomicrons formed in rats receiving TO intraduodenally, with 95% of the remnant disintegrations per minute (dpm) being in TG. The 3H-remnants were infused intravenously into rats receiving either saline or 135 mumol/h TO intraduodenally. In the saline-infused rats, 32% of the infused 3H dpm were in the proximal and 19% in the distal intestine and 32% were in the liver. In the fat-infused rats, 12% of the infused 3H dpm were in the proximal and 5% were in the distal gut and 29% were in the liver. When [3H]cholesterol-labeled remnants were infused intravenously and saline was infused intraduodenally, the percentage uptake into the mucosa was nearly the same as with the TG label, but comparable uptake by the liver increased. We conclude that the intestine competes with the liver for chylomicron remnant TG and cholesterol.

Portal transport of long acyl chain lipids: effect of phosphatidylcholine and low infusion rates

The transport of absorbed long acyl chain lipids in the portal vein of rats has been shown to be 39% when the duodenal input rate is 135 mumol/h glyceryl trioleate (TO) [C. M. Mansbach II, R. F. Dowell, and D. Pritchett, Am. J. Physiol. 255 (Gastrointest. Liver Physiol. 18): G530-G539, 1991]. These calculations were based on a new experimental model in which portal flux is calculated from the knowledge of portal flow and the concentration of the lipids in excess in the portal vein vs. the carotid artery. To test this model, rats were infused for 6 h with a low rate of [3H]TO (27 mumol/h) with or without phosphatidylcholine (9 mumol/h) or with [3H]TO (135 mumol/h) plus phosphatidylcholine (9 mumol/h) or with [3H]TO (135 mumol/h) plus phosphatidylcholine (9 mumol/h). In all three cases, portal flux was expected to be less. Portal transport was 16.5% of the input rate in the low-dose group, 1.4% in the high-dose group given phosphatidylcholine, and 0.5% in the low-dose plus phosphatidylcholine group. There was no net transport of fatty acid in the portal vein in any of the three cases. These data show that portal lipid transport is dependent on the lipid load and that it is greatly reduced at high loads by including phosphatidylcholine in the lipid infusion.