Expansion properties often homoionic smectites that differed in amount and location of layer charge were examined by X-ray powder diffraction analysis at various relative humidities, or after glycerol or ethylene glycol solvations. Except for K-samples with glycerol solvation, and Na- and Ca-samples with ethylene glycol, differences in the basal spacings are observed in samples having similar layer charge. These results show that the basal spacings are larger when the layer charge is located in octahedral sites than when it is in tetrahedral sites. This suggests that expansion is due to the combined effects of the charge location and amount.

The effects of layer charge magnitude and location on expansion were represented by an energy change (expansion energy: ΔEr) during the hydration and solvation processes. Plots of basal spacings versus ΔEr show a reasonable relationship; the spacings generally decrease stepwise as the value of ΔEr increases. The basal spacings of K-samples with glycerol solvation, Na-saturated and K-saturated samples at 100% RH are apt to contract stepwise with increasing value of ΔEr. For these samples, the figures showing the relationship between each expanded phase and the charge characteristics are obtained from the isoquants of ΔEr, given the boundary of the expanded phases. A behavior test using these figures may be combined with the Greene-Kelly test to estimate the amount and the location of the layer charge of common smectites.

Glycerol is a byproduct of biodiesel synthesis by transesterification of triglycerides with short-chain alcohols in the presence of solid base catalysts. Because hydrotalcite is a potentially useful basic catalyst for the transesterification reaction, the interaction of glycerol with hydrotalcite is the focus of this work. Glycerol was intercalated into Mg-Al hydrotalcite with a Mg/Al molar ratio of 4 under elevated temperatures of 4432/503 K in the absence and presence of NaOH. The resulting materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and N2 adsorption. The amount of glycerol incorporated into hydrotalcite increased with increasing temperature of intercalation. However, the brucite-like sheets of hydrotalcite partially decomposed during the intercalation process at the highest temperature. The presence of NaOH stabilized the hydrotalcite layers against decomposition under high temperature (503 K). The intercalated materials exposed large surface areas ranging from 142 to 663 m2 g−1, depending on the preparation conditions. The glycerol-intercalated hydrotalcites were less catalytically active than hydrotalcite with OH− counterions for the transesterification of tributyrin with methanol. The lower reactivity of glycerol-intercalated hydrotalcite was probably the result of a strong interaction between the intercalated glycerolate (HOCH2-CHOH-CH2O−) and the partially decomposed brucite-like sheets.

Montmorillonite (Mnt)-based solid acids have a wide range of applications in catalysis and adsorption of pollutants. For such solid acids, the acidic characteristic often plays a significant role in these applications. The objective of the current study was to examine the effects of H3PO4-activation and supporting WO3 on the textural structure and surface acidic properties of Mnt. The Mnt-based solid acid materials were prepared by H3PO4 treatment and an impregnation method with a solution of ammonium metatungstate (AMT) and were examined as catalysts in the dehydration of glycerol to acrolein. The catalysts were characterized by nitrogen adsorption-desorption, powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), diffuse reflectance ultraviolet-visible (DR UV-Vis) spectroscopy, temperature programmed desorption of NH3 (NH3-TPD), diffuse reflectance Fourier-transform infrared (DR FTIR) spectroscopy of adsorbed pyridine, and thermogravimetric (TG) analyses. The phosphoric acid treatment of Mnt created Brönsted and Lewis acid sites and led to increases in specific surface areas, porosity, and acidity. WO3 species influenced total acidity, acid strength, the numbers of Brönsted and Lewis acid sites, and catalytic performances. A high turnover frequency (TOF) value (31.2 h−1) based on a maximal 60.7% yield of acrolein was reached. The correlation of acrolein yield with acidic properties indicated that the cooperative role of Brönsted and Lewis acid sites was beneficial to the formation of acrolein and a little coke deposition (<3.3 wt.%). This work provides a new idea for the design of solid acid catalysts with cooperative Brönsted and Lewis acidity for the dehydration of glycerol.

This study was performed to determine the effects of crude glycerin (CG) supplementation in drinking water on DM and nutrient intake, milk production, milk composition, and serum glucose. Twenty multiparous Lacaune × East Friesian ewes were randomly distributed into four dietary treatments throughout the lactation cycle. Treatments consisted of doses of CG supplementation via drinking water as follows: (1) no CG supplementation, (2) 15.0 g CG/kg DM, (3) 30.0 g CG/kg DM, and (4) 45.0 g CG/kg DM. DM and nutrient intake were reduced linearly with CG supplementation. CG linearly reduced water intake when expressed as kg d−1. However, no effect of CG was observed when it was expressed as a percentage of body weight or metabolic body weight. The water to DM intake ratio was increased linearly with CG supplementation. No effect of CG doses on serum glucose was observed. The production of standardized milk decreased linearly with the experimental doses of CG. Protein, fat, and lactose yield were linearly reduced with the experimental doses of CG. Milk urea concentration was quadratically increased with CG doses. Feed conversion was quadratically increased by treatments during the pre-weaning period (P < 0.05), in which the worst values were observed when the ewes were supplemented with 15 and 30 g CG/kg DM. The N-efficiency was linearly increased with CG supplementation in drinking water. Our results suggest that dairy sheep can be supplemented with CG up to 15 g/kg DM in drinking water. Greater doses are not beneficial for feed intake, milk production, and the yield of milk components.

The objective of this study was to explore the metabolic profiles of pregnancy malnutrition induced by feed restriction (FR) and the counteracting effects of glycerol and rumen-protected choline chloride supplementation. Two feeding trials were conducted. In the first experiment, twenty pregnant Hu sheep carrying multiple fetuses with a gestation period of 108 d were randomly divided into two groups. The ewes in the control (CON) group were offered 100 % of their nutritional requirements as recommended by the National Research Council (NRC), while the FR group was offered 30 % of feed intake of CON for 15 d. In the second experiment, eighteen pregnant Hu sheep were offered a feed intake comprising 30 % of the NRC-recommended nutritional requirements twice daily. The sheep were randomly divided into three groups: the FR group in the second experiment (FR2), with no supplementation, the glycerol (GLY) group, which received 40 ml of glycerol per d, and the rumen-protected choline chloride (RPC) group, which received 10 g of rumen-protected choline chloride per d for 9 d. In the first experiment, the urine metabolome of sixteen ewes showed significant difference between the CON group and FR group. Compared with the CON group, FR decreased the level of d-glucose, lactic acid, levoglucosan, α-ketoglutarate, phosphohydroxypyruvic acid, glucose 6-phosphate and the methyl donors, while increasing the level of pyruvate, fumaric acid and carnitines in urine. Both the GLY and RPC treatments counteracted some of these changes and modulated the urine metabolome in advanced pregnant ewes suffering from malnutrition.

A novel flexible radio frequency (RF) sensor is designed to facilitate the accurate testing of various samples used in the biomedical industry at the industrial, scientific and medical (ISM) frequency band. The proposed RF biosensor comprises a liquid channel-loaded interdigitated capacitor, which is integrated on a coplanar waveguide structure. The prototype of the sensor is fabricated on a 0.13 mm thin biodegradable polyethylene terephthalate polyester film to perform the testing of various bio-graded samples by recording the corresponding resonant frequency. It is observed that there is a noticeable change between the measured resonant frequencies of these samples, which primarily occurs due to the difference in their dielectric properties. The designed sensor was used to monitor and investigate the quality of glycerol, which is the most commonly used raw ingredient in the biomedical and food industry. The determination of glucose concentration in base fluids is considered to ease the challenges faced by doctors and biochemists regarding the monitoring of glucose concentration. It is found that the proposed sensor can quantify the glycerol purity up to the minimum specified adulteration level of 2 and 1% corresponding to toxic contaminants diethylene glycol and ethylene glycol, respectively, and the glucose concentration of 0.5 mg/ml.

In this study, polyploidy level was determined by flow cytometry analysis. The effect of polyploidy by colchicine treatment was examined on the growth parameters, malondealdehyde (MDA), as well as activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in response to different levels of salinity in Dunaliella salina. The results of algal growth indicated that 3 M NaCl was the optimal concentration of salt, since the highest enhancement in fresh and dry weight, chlorophyll and carotenoids, soluble sugar, glycerol, protein and starch content was observed in comparison to other concentrations. The amount of these metabolites declined in the concentrations under optimum salinity. The least and highest amounts of MDA were observed at 1 and 4 M NaCl respectively. Polyploidy in optimum concentration of salt, caused further increment of the above growth parameters. In relation to this, in most cases, treatment of 0.1% colchicine was most effective. The beneficial effects of polyploidy in non-optimal conditions were also found in some parameters such as biomass, chlorophyll, carotenoids, proteins and starch. Furthermore, the activity of antioxidant enzymes CAT, SOD and POD showed a positive significant correlation with salt stress and these were maximized at 4 M NaCl. Polyploidy (especially colchicine 0.1%) affected activity of these antioxidant enzymes in some concentrations of salt. Overall, our results suggest that the microalgae has significantly different responses to salt stress based on ploidy levels.

The aim of the current study was to evaluate the effect of different forms of soybean lipids on enteric methane emission, intake, performance, digestibility and meat quality of 40 young Nellore bulls (initial body weight (BW) 444 ± 10.2 kg and 24 ± 2.1 months). The dietary treatments were as follows: NF = no dietary additional fat (46.0 g ether extract (EE)/kg diet), SO = soybean oil (62.0 g EE/kg diet), SB = soy beans (without any processing; 62.0 g EE/kg diet) and RPF = rumen-protected fat based on soybean oil (62.0 g EE/kg diet). The intake of dry matter (DM), organic matter (OM), crude protein (CP) and neutral detergent fibre (NDF) was greater in the SO diet than those fed with NF. The SO diet decreased digestibility of NDF when compared with the NF and RPF diets. The diets did not affect digestibility of DM, OM, CP or emission of enteric methane. Animals fed with SO had greater average daily gain and feed efficiency in relation to the other diets tested. The SO diet increased hot and cold carcass weights and subcutaneous fat thickness of carcasses when compared with the NF diet. The proportions of saturated and unsaturated, mono and polyunsaturated, and n-3 and n-6 fatty acids were not affected significantly by treatments. The SO diets were demonstrated to be more beneficial for animal performance compared with diets without supplemental fat.

The aim of this study is to assess how the fat molecular structure and its glycerol-to-fatty acid ratio (G : FA) affect the fatty acid (FA) apparent absorption of palm oils in broiler chickens. The experimental diets were the result of a basal diet supplemented with 6% of different palm oils. Native palm oil (N), rich in triacylglycerols, was the positive control (T1), and acid palm oil (A), rich in free FA, was the negative control (T2). In order to improve the nutritive value of A, two different nutritional strategies were performed. The first strategy was achieved by adding increasing amounts of free glycerol (G) (4% (T3), 8% (T4) and 16% (T5)) to A, and the second one by adding increasing amounts of mono- (MAG) and diacylglycerols (DAG), coming from re-esterified palm oil (E) (40% (T6), 70% (T7), and 100% (T8)) to A. As a result, eight dietary treatments were formulated with a G : FA ratio ranging from 0.04 to 0.67. These treatments were randomly assigned to 192 one-day-old female broiler chickens (Ross 308), distributed in 48 cages. The results showed how, by keeping the G : FA ratio constant (0.33 mol/mol), the diet with a high MAG and DAG content (T7) achieved higher saturated FA apparent absorption values than did the diet with a high triacylglycerol content (T1) and this, in turn, more than did the diet with a high free FA content (T4). The behavior of oils with high or low G : FA ratio was dependent on whether G was in a free state or esterified as part of acylglycerol molecules. Thus, increasing amounts of G to A did not enhance the total FA apparent absorption, but rather quite the opposite, even impairing the absorption of mono- and polyunsaturated FA. However, increasing amounts of E (rich in MAG and DAG) to A (rich in FFA) did enhance total FA apparent absorption, primarily due to the increased absorption of saturated FA. In conclusion, the greater the G : FA ratio of a palm oil, the greater the absorption of total FA, as long as G is esterified as part of acylglycerol molecules. Thus, the re-esterification process for obtaining E makes sense in order to give added value to A, achieving even greater digestibility values than does its corresponding N.

The objective of this study was to determine whether a combination of crude glycerin (CG) and soyabean oil (SO) could be used to partially replace maize in the diet of Nellore steers while maintaining optimum feed utilisation. Eight castrated Nellore steers fitted with ruminal and duodenal cannulas were used in a double 4×4 Latin square design balanced for residual effects, in a factorial arrangement (A×B), when factor A corresponded to the provision of SO, and factor B to the provision of CG. Steers feed SO and CG showed similar DM intake, DM, organic matter and neutral-detergent fibre digestibility to that of steers fed diets without oil and without glycerine (P>0·05). Both diets with CG additions reduced the acetate:propionate ratio and increased the proportion of iso-butyrate, butyrate, iso-valerate and valerate (P<0·05). Steers fed diets containing SO had less total N excretion (P<0·001) and showed greater retained N expressed as % N intake (P=0·022). SO and CG diet generated a greater ruminal abundance of Prevotella, Succinivibrio, Ruminococcus, Syntrophococcus and Succiniclasticum. Archaea abundance (P=0·002) and total ciliate protozoa were less in steers fed diets containing SO (P=0·011). CG associated with lipids could be an energy source, which is a useful strategy for the partial replacement of maize in cattle diets, could result in reduced total N excretion and ruminal methanogens without affecting intake and digestibility.

Two experiments were conducted to evaluate the effects of replacing corn with an increasing concentration of high-purity glycerol (>99%) on growth performance, economical efficiency, blood constituents and nutrient digestibility of growing lambs. In experiment one, 24 male lambs (initial BW=33.6±6.0 kg; age=6.75±0.75 months) were randomly assigned to one of the three experimental treatments containing 0%, 5% or 10% glycerol to replace corn in concentrate. In experiment two, nine lambs (initial BW=44.7±2.2 kg, age=8.84±0.32 months) were used in a digestion trial with three treatments (three lambs per treatment) with glycerol replacing corn at 0%, 5% or 10% in the concentrate. Total dry matter (DM) intake decreased quadratically (P=0.003) with increasing concentration of glycerol in the diet. Lambs fed glycerol diets had greater average daily gain (P=0.005) and better feed efficiency (P=0.002) compared with the control. Feed costs were also reduced with glycerol inclusion. Glycerol supplementation did not affect serum concentrations of total protein, albumin, globulin, total lipid, cholesterol and glucose concentrations. Glycerol supplementation had no effect (P>0.05) on organic matter and CP digestion, but improved DM (P=0.0003), crude fiber (P=0.10), ether extract (P=0.0002) and nitrogen-free extract (P=0.05) digestion. In conclusion, glycerol can replace corn up to 10% of DM in the diets of growing lambs.

This study was conducted to evaluate the effect of increasing levels of glycerol in the diet on milk yield and composition, diet digestibility and some blood metabolites of dairy buffaloes in early lactation. A total of 24 buffaloes were blocked by average milk yield, parity and BW and then randomly assigned to three treatments: control without glycerol (CON); low glycerol (LG): control plus glycerol at 150 ml/day per buffalo; and high glycerol (HG): control plus glycerol at 300 ml/day per buffalo. The experimental period lasted for 60 days. Feeding LG and HG decreased (P<0.0001) dry matter intake compared with the CON. Buffaloes supplemented with LG and HG produced more milk (P<0.01) and had a greater (P<0.0001) yield of fat-corrected milk (3.5%) than those buffaloes fed control treatment. Glycerol-supplemented buffaloes showed a positive energy status indicated by reduced concentrations of non-esterified fatty acids and β-hydroxybutyrate. Feeding LG and HG tended to increase (P⩽0.10) concentrations of milk fat, and serum total protein and globulin and significantly decreased (P⩽0.05) milk urea nitrogen and somatic cells counts (SCCs) compared to the CON group. Inclusion of LG and HG had no effect on organic matter and non-fiber carbohydrate digestion, but improved dry matter (P=0.02), CP (P=0.09), ether extract (P=0.03), NDF (P=0.07) and ADF (P=0.03) digestion.

Crude glycerin, a potential energy source for ruminant animals, has been evaluated, mainly, in diets with high starch content. However, a limit number of studies have evaluated the inclusion of crude glycerin in low starch diets. This study aimed to evaluate the effects of the association of crude glycerin with corn grain or citrus pulp on carcass traits and meat quality of Nellore bulls (n=30, 402±31 kg initial weight). The treatment consisted of: CON=control, without crude glycerin; CG10=10% of crude glycerin and corn grain; CG15=15% of crude glycerin and corn grain; CP10=10% of crude glycerin and citrus pulp; CP15=15% of crude glycerin and citrus pulp. The performance parameters and carcass traits were not affected by treatments (P>0.05). The inclusion of crude glycerin decreased yellow color intensity and increased fatty acids pentadecanoic and heptadecenoic in meat (P<0.05), without affecting neither the concentration of polyunsaturated fatty acids nor the relationship of saturated and unsaturated fatty acids. The association of crude glycerin with corn or citrus pulp has no adverse effects on carcass characteristics and meat quality.

The objective of this experiment was to replace soya bean oil with glycerol in laying hen diets and assess the change’s effect on performance, parameters of egg quality and the egg fatty acid profile. A total of 60 44-week-old Hy-Line W36 laying hens were distributed according to a completely randomised experimental design into four treatments consisting of glycerol substitutions for soya bean oil dietary at varying inclusion levels (0%, 25%, 50% and 75%), with five replicates of three birds each. Dietary treatments had no significant effect on BW change, egg production, feed intake, feed conversion ratio, egg weight and egg mass of laying hens. The inclusion of glycerol in the diet of laying hens had no significant effect on egg specific gravity, eggshell breaking strength, eggshell weight, eggshell thickness, egg shape index, albumen index, yolk index, haugh unit, albumen pH, yolk pH and egg yolk colour values. The inclusion of glycerol in the diet of laying hens had no significant effect on palmitic, palmitoleic, stearic, oleic and linolenic acid contents of the egg yolk. The linoleic acid and polyunsaturated fatty acid contents of the egg yolk significantly decreased with the higher levels of dietary glycerol supplementation (P<0.05). The results of this study show that it is possible to replace 75% of soya bean oil (4.5% in diet) with glycerol.

The effect of sex, source of saturated fat (lard v. palm oil) and glycerol inclusion in the fattening diet on composition and fatty acid positional distribution in the triglyceride molecule was studied in pigs from 78 to 110 kg BW. Average daily gain and carcass characteristics, including ham and loin weight, were not affected by dietary treatment but sex affected backfat depth (P<0.01). A significant interaction between sex and glycerol inclusion was observed; dietary glycerol increased lean content in gilts but not in barrows (P<0.05 for the interaction). Individual and total saturated fatty acid (SFA) concentrations were greater in barrows than in gilts. In contrast, the concentration of total polyunsaturated fatty acids (PUFA) and of C18:2n-6, C18:3n-3, C20:3n-9 and C20:4n-6 in the intramuscular fat (IMF) was higher (P<0.05) in gilts than in barrows. Sex did not affect total monounsaturated fatty acids (MUFA) concentration in the IMF. The proportion of SFA in the subcutaneous fat (SF) was higher in barrows than in gilts (P<0.001). Within the individual SFA, sex affected only the concentrations of C14:0 and C16:0 (P<0.001). Dietary fat did not affect total SFA or PUFA concentrations of the IMF but the subcutaneous total MUFA concentration tended to be higher (P=0.079) in pigs fed lard than in pigs fed palm oil. Dietary glycerol increased total MUFA and C18:1n-9 concentration in the IMF and increased total MUFA and decreased C18:2n-6, C18:3n-3 and total PUFA concentrations in the SF. The data indicate that altering the fatty acid composition of the triglyceride molecule at the 2-position, by dietary intervention during the fattening phase, is very limited.

The gut health of poultry is closely associated with feeds and feeding. The experiment was conducted to the effect of crude glycerol addition to diets of male broilers on the bacterial microflora and morphology of their small intestines (duodenum, jejunum and ileum). A total of 120 Ross 308 broiler chicks received diets containing 0% (GLY 0), 4% (GLY 4) or 8% (GLY 8) crude glycerol for 42 days. The presence of Coliform bacteria and Enterobacteria was reduced in the duodenal tract of the broilers of GLY 4 (P<0.001); however, the presence of Staphylococci/Micrococci in the GLY 8 was reduced relative to the other groups (P<0.001). The presence of Salmonella spp. decreased in conjunction with the increasing quantities of glycerol (P<0.001). Analysis of the data regarding gut morphology (epithelial cell thickness, villi length and width, and crypt length and width) indicated that the glycerol levels fed to the different groups of broilers represented statistically different results in the small intestine. In general, whereas the diet with 4% glycerol statistically affected the investigated parameters of the gut, the diet with 8% glycerol statistically affected some segments of the broiler intestines.

This study evaluated the effects of supplemental low- and high-purity glycerine on silage intake, milk yield and composition, plasma metabolites and body condition score (BCS) in dairy cows. A total of 42 cows of the Swedish Red Breed, housed in individual tie stalls, were fed 0.25 kg of low- or high-purity glycerine on top of concentrate, twice daily, during the first 4 weeks of lactation. One-third of the cows acted as controls, receiving no glycerine. Silage was fed for ad libitum intake and concentrate was fed at restricted level of intake, about 6 kg/day for primiparous cows and 7 kg/day for multiparous cows. Feed refusals were weighed daily. Cows were milked twice daily, milk yield was recorded on four occasions per week and milk samples were collected simultaneously. Blood samples were drawn from the coccygeal vessel once a week. Low- and high-purity glycerine had no effect on silage or total dry matter intake (P = 0.38 and P = 0.75, respectively) or on BCS (P = 0.45). Cows fed high-purity glycerine tended to have higher milk yield than control cows (P = 0.06). Milk composition tended to differ among treatments. No main effects of treatment on concentration of glycerine (P = 0.44), glucose (P = 0.78), insulin (P = 0.33), non-esterified fatty acids (P = 0.33) and β-hydroxybutyrate (P = 0.15) in plasma. These data indicate that high-purity glycerine has the potential to increase milk yield, as well as enhance the milk protein concentration and milk fat + protein yield.

As grain prices rise, the search for alternative glycogenic precursors in animal feed becomes increasingly important, and this study was conducted to determine if the replacement of starch with glycerol, as an alternative glycogenic precursor, affects the milk metabolic profile and milk coagulation ability, and therefore the quality of the milk. Eight primiparous mid-lactation Holstein cows were fed during a replicated 4 × 4 Latin square trial with four different isoenergetic rations: (1) control (T0) fed a total mixed ration (TMR) with barley meal; (2) group T1, decreased barley content, replaced isoenergetically with 1 kg crude glycerol; (3) group T2, the barley meal was replaced with 2 kg of crude glycerol; and (4) group T3 the barley meal was replaced with 3 kg of crude glycerol. Rumen, blood and milk samples were collected at the end of every 21-d treatment period. Rumen samples were analysed for proportion of total volatile fatty acid (VFA), blood samples for insulin and glucose, and milk for metabolites (e.g. citric-acid cycle compounds). The change in glycogenic precursors had a positive effect on rumen VFA proportions; the proportion of propionic acid increased (P < 0·001). Milk protein (P < 0·001) and curd firmness (P < 0·001) both increased. The increase in milk protein concentration may have been due to an increase in microbial protein. Regarding the milk metabolic profiles, different signals were positively associated with coagulation ability and change in the diet. Based on this study, changing the glycogenic precursor in animal diet in this way is possible, and may have no immediate deleterious consequences on milk quality or cow health. Indeed, there is evidence for benefits from this substitution.

We evaluated the effect of glycerol on the perinuclear theca (PT) of boar sperm. Samples from six ejaculates obtained from three different boars were incubated in the detergent Brij 36-T. Spermatozoa were treated with a glycerol concentration of either 2 or 4%, and incubated for 10 or 30 min; two other samples were treated with protease inhibitors (PI; leupeptin or an inhibitor commercial cocktail), mixed with 4% glycerol, and incubated for 30 min. A third glycerol-free group was used as the control. The samples were processed for electron microscopy evaluation. The PT remained intact in 78% of the control samples while, after addition of glycerol for 30 min, the proportion of spermatozoa with disrupted or absent PT increased (P < 0.05). PT was preserved in PI samples, but PT changes increased (P < 0.05). Differences due to treatment with glycerol (2 or 4%) at 10 or 30 min were not observed. These results show, to our knowledge for the first time, the adverse effect of glycerol on the integrity of the PT.