Inclusion Of Glycerol Research Articles

Solvent‐Induced Dynamic Bond Regulation for Constructing Adaptive Lubricating Hydrogels with Switchable Tribological Performance and Environmental Adaptability

AbstractAdaptive lubricating hydrogels (ALH) show promise for reducing friction and energy consumption in various industrial applications. However, retarded switchable tribological performance and poor environmental adaptability limit their integration into application devices. Herein, a dynamic bond regulating strategy based on solvent conversion for producing an ALH with highly switchable tribological performance and decent environmental tolerance is proposed. By incorporating dynamic B─O bonds into the sodium alginate (SA) framework, these bonds transition between associative and dissociative states, facilitated by solvent conversion between glycerol and ethanol. This process modulates the mechanical modulus of the SA network, allowing for achieving highly switchable tribological performance. Furthermore, the inclusion of glycerol not only as a modulus regulator but also serves as an antifreeze component to impart the ALH with superior antifreeze and heat resistance properties, thus allowing the ALH to demonstrate excellent environmental adaptability. As a result, the resulting ALH exhibits highly switchable lubrication behavior, with a dynamically adjustable coefficient of friction (COF) between 0.022 and 0.157, and maintains consistent lubrication performance under a harsh environment (−40–60 °C), representing the state‐of‐the‐art in reported ALHs. This advancement allows for the development of intelligent brake devices (IBD), demonstrating potential applications in controlling drone speed.

Glycerol supplementation in farmed fish species: A review from zootechnical performance to metabolic utilisation

AbstractGlycerol, an abundant by‐product of biodiesel production, has gained attention due to its price and availability for potential commercial applications, and thus utilisation as an animal feed ingredient. This article comprehensively reviews glycerol utilisation in fish and its potential as a dietary ingredient for aquaculture. While dietary inclusion of glycerol may offer cost‐effective energy and metabolic intermediates, studies report inconsistent results regarding its effects on nutrient digestibility, zootechnical performance, and product quality. Recent studies however have demonstrated that dietary glycerol supplementation in fish induces metabolic shifts, such as alterations to gluconeogenesis and/or lipogenesis, modifying energy utilisation. Additionally, glycerol has been proposed to reduce protein catabolism, minimising nitrogen excretion and its environmental impact, but its influence on protein retention remains uncertain. Nevertheless, it is important to carefully consider the balance between feed palatability and these potential metabolic alterations when incorporating glycerol in aquafeeds. This review highlights the need for more studies to expand our understanding of glycerol metabolism in fish, since it does not seem to be metabolised by carnivorous species as much as omnivorous. Future research should explore the effects of glycerol supplementation on fish with different feeding habits and in developmental stages, as well as diverse environmental salinities and temperatures. Insight into the impact of impurities and the optimisation of glycerol inclusion in aquafeeds are recommended to support sustainable aquaculture practices and the utilisation of glycerol as a valuable resource.

Transparent, plasticized cellulose-glycerol bioplastics for food packaging applications

Free-standing films have been obtained by drop-casting cellulose-glycerol mixtures (up to 50 wt% glycerol) dissolved in trifluoroacetic acid and trifluoroacetic anhydride (TFA:TFAA, 2:1, v:v). A comprehensive examination of the optical, structural, mechanical, thermal, hydrodynamic, barrier, migration, greaseproof, and biodegradation characteristics of the films was conducted. The resulting cellulose-glycerol blends exhibited an amorphous molecular structure and a reinforced H-bond network, as evidenced by X-ray diffraction analysis and infrared spectroscopy, respectively. The inclusion of glycerol exerted a plasticizing influence on the mechanical properties of the films, while keeping their transparency. Hydrodynamic and barrier properties were assessed through water uptake and water vapor/oxygen transmission rates, respectively, and obtained values were consistent with those of other cellulose-based materials. Furthermore, overall migration levels were below European regulation limits, as stated by using Tenax® as a dry food simulant. In addition, these bioplastics demonstrated good greaseproof performance, particularly at high glycerol content, and potential as packaging materials for bakery products. Biodegradability assessments were carried out by measuring the biological oxygen demand in seawater and high biodegradation rates induced by glycerol were observed.

On the Unique Morphology and Elastic Properties of Multi-Jet Electrospun Cashew Gum-Based Fiber Mats.

This study investigates the unique morphology and mechanical properties of multi-jet electrospun cashew gum (CG) when combined with high-molecular-weight polyethylene oxide (PEO) and glycerol. Cashew gum (CG) is a low-cost, non-toxic heteropolysaccharide derived from Anacardium occidentale trees. Initially, the electrospinnability of aqueous solutions of cashew gum alone or in combination with PEO was evaluated. It was found that cashew gum alone was not suitable for electrospinning; thus, adding a small quantity of PEO was needed to create the necessary molecular entanglements for fiber formation. By using a single emitter with a CG:PEO ratio of 85:15, straight and smooth fibers with some defects were obtained. However, additional purification of the cashew gum solution was needed to produce more stable and defect-free straight and smooth fibers. Additionally, the inclusion of glycerol as a plasticizer was required to overcome material fragility. Interestingly, when the optimized formulation was electrospun using multiple simultaneous emitters, thicker aligned fiber bundles were achieved. Furthermore, the resulting oriented fiber mats exhibited unexpectedly high elongation at break under ambient conditions. These findings underscore the potential of this bio-polysaccharide-based formulation for non-direct water contact applications that demand elastic properties.

Preparation and characterization of peach gum/chitosan polyelectrolyte composite films with dual cross-linking networks for antibacterial packaging

Peach gum (PG) is a valuable polymeric feedstock for developing eco-friendly, bio-safe, and functional materials. However, PG has limited use in food packaging due to its inferior mechanical and antibacterial properties. To overcome these limitations, we created a dual cross-linked network by introducing chitosan (CS) and glycerol to the PG matrix. Our research discovered that incorporating CS into the PG matrix significantly improved its Young's modulus, from 277.62 to 925.89 MPa, and its tensile strength from 5.96 to 39.94 MPa. Furthermore, the inclusion of glycerol greatly increased the elongation. These enhancements were attributed to the ionic and hydrogen-bonding interactions between the two biopolymers. Additionally, the composite films exhibited strong antibacterial effects, reducing the total number of colonies by 99.2 % and 99.9 % against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively. The incorporation of CS resulted in more amorphous films, enhancing their stiffness, flexibility, and barrier properties. To assess the practical application of PG/CS composite films, we conducted a comparative analysis between non-packaged strawberries and strawberries packaged with these films. The results demonstrated that the composite polyelectrolyte film extended the shelf life of strawberries better than the non-packaged fruits.

Nanoscale Liposome Synthesis for Drug Delivery Applications via Ultrafast Acoustofluidic Micromixing

Nowadays, lipid nanoparticles have gained profound interest in chemical and biomedical engineering. The rapid development of therapeutic nanosystems has led to a need to design suitable approaches to synthesize bio-carriers for efficient drug delivery. Microfluidic methods provide an excellent opportunity to acquire desirable nanoparticle properties, including stability, size, shape, and size distribution, which are often challenging to obtain using conventional bulk synthesis methods. Rapid mixing is a crucial factor in the nanoprecipitation process as it influences the size and size distribution of the nanoparticles. Within this regard, in this work, we report an ultrafast acoustofluidic micromixer to synthesize liposome nanoparticles, which have been widely investigated in the literature as drug carriers due to their biocompatibility and biodegradability. This research has also investigated the influence of glycerol addition to the solvent to control the size of the liposomes. Our findings indicate that utilizing the acoustofluidic platform resulted in the production of nanoscale liposomes with small mean sizes compared to the hydrodynamic flow-focusing (HFF) method. Furthermore, the inclusion of glycerol led to a significant reduction in liposome size. These results emphasize the potential of the proposed approach for the efficient and precise synthesis of liposome nanoparticles with improved characteristics, which can be utilized in various biomedical and drug delivery applications.

Development of highly reusable, mechanically stable corn starch-based aerogel using glycerol for potential application in the storage of fresh spinach leaves

Impact of glycerol on the physico-functional, morphological, mechanical, and rehydration properties of corn starch-based aerogel has been investigated. The aerogel was prepared from hydrogel (sol-gel method) using solvent exchange and supercritical CO2 drying. Glycerol-infused aerogel had a more connected, denser structure (0.38–0.45 g/cm3), enhanced hygroscopic behavior, and was reusable up to eight times in terms of its capacity to absorb water after being drawn from the soaked sample. However, the inclusion of glycerol reduced the aerogel's porosity (75.89–69.91 %) and water absorption rate (WAR; 118.53–84.64 %) but enhanced its percentage shrinkage (75.03–77.99 %) and compressive strength (26.01–295.06 N). The most effective models for describing the rehydration behavior of aerogel were determined to be the Page, Weibull, and Modified Peleg models. Glycerol addition improved the internal strength of the aerogel so could be recycled without significant change in the physical characteristics of the aerogel. By effectively eliminating the condensed moisture that was developed inside the packing owing to the transpiration of fresh spinach leaves, the aerogel extended the storage life of the leaves by up to eight days. The glycerol-based aerogel has the potential to be employed as a carrier matrix for various chemicals and a moisture scavenger.

Crosslinking of Starch Using Citric Acid

With a purpose of improving mainly the water resistivity and related physical and mechanical property of starch biopolymer, citric acid was used to modify the chemical structure of starch by crosslinking the polymer chains. Corn starch films were produced first dispersing 4% (w/w) starch in water, adding glycerol (36% of the weight of starch) and citric acid (20% of the weight starch) successively allowing them to react at different pH. Water absorption, FTIR, DMA, DSC and SEM tests were done to characterize the thin film samples. Results showed that availability of glycerol is a critical factor for the crosslinking and plasticity property of the film. Samples prepared with citric acid crosslinked starch without the inclusion of glycerol were brittle and has easily disintegrated in water as crystals. The crosslinking reaction done under acidic condition was found more effective than the other reactions. Generally, citric acid has effectively crosslinked corn starch polymer molecules reducing the amount of hydroxyl group in their structure. As a result improvement in the water resistant is observed.

Cryoprotective agents influence viral dosage and thermal stability of inhalable dry powder vaccines

Increasing viral dosage within dry powder vaccines reduces the powder mass required to elicit an immune response through pulmonary delivery. This work analyzes how cryoprotective agents affect viral activity, particle properties and thermal stability of a spray dried, inhalable vaccine vector under high viral loading. Stock suspensions of a human serotype 5 adenovirus (AdHu5) vector in either neat phosphate buffered saline (PBS), 10% glycerol in PBS, or 5% trehalose in PBS were added to a mannitol-dextran formulation prior to spray drying. At high viral loading, spray dried powder containing glycerol had a viral titre log loss of 2.8 compared to 0.7 log loss using neat PBS. Powders containing glycerol had a lower glass transition temperature (Tg) compared to all other formulations, permitting greater viral mobility and exposure to heat damage. Inclusion of glycerol also promoted particle cohesion during spray drying and lower yields. Using 5% trehalose as a cryogenic alternative, viral powders had a viral log loss of 1.5 and the highest displayed thermal stability over time. Additionally, trehalose-containing powders had smaller particles with lower water moisture content and higher powder yield compared to glycerol-containing powders. These findings demonstrate the importance of cryoprotective agent selection when developing thermostable vaccine powders.

Towards a semi-automated analysis of fish plasma by 1H NMR metabolomics - applications to aquaculture

Aquafeed is one of the main costs in aquaculture and major efforts are being made to find sustainable ingredients that could improve production sustainability and efficiency. Our research focused on the inclusion of glycerol in the feed of European seabass (Dicentrarchus labrax), as it is a cheap carbon substrate expected to enter metabolism through the glycolytic pathway. The Nuclear Magnetic Resonance (NMR) spectroscopy provides accurate and high-throughput metabolic profiles, allowing quantification and evaluation of the effects of experimental diets in the context of fish nutrition. The aim of the present study was to assess the applicability of the automated online profiling routine Bayesil to fish blood plasma and compare with the manual targeted metabolite profiling approach.After a 60-day feeding trial (0%, 2.5%, 5.0% glycerol supplemented diets), fish were sacrificed at 6 h and 24 h after last meal and blood was sampled. Filtered plasma samples were analysed by NMR, followed by two metabolite-profiling approaches: i) an automated spectral profiling provided by the Bayesil platform, and ii) a manual metabolite profiling.Spectra were analysed with the automated Bayesil routine, identifying and quantifying 51 metabolites, in a reproducible, fast and user-independent method. On the other hand, the manual approach only managed to quantify 20 metabolites. However, under supraphysiological concentrations of glycerol, namely in the 5.0% diet, the Bayesil algorithm was not able to properly integrate the glycerol and glycine signals. The Bland-Altman and PLS-DA analysis revealed differences; nonetheless, with the exception of acetic acid, creatinine, formate, glutamine and threonine, all other metabolites presented a low bias and/or a strong correlation coefficient. Overall, it is expected a reasonable tradeoff between the accuracy in metabolite quantification and the increase of variables.The automated Bayesil database may be applied as a useful tool for systematic monitoring of fish plasma profile in aquaculture research and industrial quality control analysis, to generate robust variance-based multivariate statistical models. To our knowledge, this is the first time a NMR-based high-throughput automated routine is evaluated for aquaculture research.

A case for glycerol as an acceptable additive for single-particle cryoEM samples.

Buffer-composition and sample-preparation guidelines for cryo-electron microscopy are geared towards maximizing imaging contrast and reducing electron-beam-induced motion. These pursuits often involve the minimization or the complete removal of additives that are commonly used to facilitate proper protein folding and minimize aggregation. Among these admonished additives is glycerol, a widely used osmolyte that aids protein stability. In this work, it is shown that the inclusion of glycerol does not preclude high-resolution structure determination by cryoEM, as demonstrated by an ∼2.3 Å resolution reconstruction of mouse apoferritin (∼500 kDa) and an ∼3.3 Å resolution reconstruction of rabbit muscle aldolase (∼160 kDa) in the presence of 20%(v/v) glycerol. While it was found that generating thin ice that is amenable to high-resolution imaging requires long blot times, the addition of glycerol did not result in increased beam-induced motion or an inability to pick particles. Overall, these findings indicate that glycerol should not be discounted as a cryoEM sample-buffer additive, particularly for large, fragile complexes that are prone to disassembly or aggregation upon its removal.

Toward Exceptional Icephobicity with Chionophile-Inspired Durable Biomimetic Coatings

Liquid-infused polymeric surfaces have demonstrated promising icephobicity. However, the capability to maintain the icephobic performance after material damage has been a challenge, both in terms of conserving a smoother surface and the replenishment of the infused liquid. Cetacean skin possesses a microscopically smooth texture in the form of cells lubricated with lipid proteins and consists of structural fibers that ensure durability. Concerning the structure of cetacean skin, glycerol-infused fiber-reinforced polyurethane (GIFRP) coatings were proposed. Instead of hosting the lipid proteins, the coatings were infused with glycerol, a known cryoprotectant to induce the supercooling of water, a strategy inspired by wood frogs and red flat dark beetles to prevent freezing. The inclusion of glycerol delayed water droplet freezing duration by 659%, while negligible frost accumulated on the fabricated coatings during anti-icing tests. The reinforcement of fibers was effective and the surface damage was reduced by a factor of 4, compared to the pure polyurethane coatings after erosion impact. The incorporation of fibers has proven to be beneficial for infused-liquid replenishment and the slow-releasing capabilities of GIFRP coatings. Minimized surface deterioration and the continued presence of glycerol on GIFRP coatings demonstrated a small increase in ice adhesion from 0.22 to 0.77 kPa after the erosion tests, one of the lowest values reported in the literature after substantial surface damage. The concept inspired by cetacean skin and the cryoprotective features of chionophiles was instrumental in keeping the ice adhesion under 1 kPa after erosion impact.

Plasma glycerol levels in men with hypertriglyceridemia

When plasma triglyceride is assessed in standard laboratories, it is a measurement of plasma glycerol after hydrolysis of triglycerides into fatty acids and glycerol. In most patients, the plasma level of free glycerol will only marginally influence the measurement of plasma triglyceride. However, in rare cases elevated free glycerol concentrations causes pseudohypertriglyceridemia and blanking for free glycerol becomes important. In this study, we investigated the plasma free glycerol level in 100 adult men with mild to moderate hypertriglyceridemia to assess the need for providing a free glycerol measurement in our clinical biochemistry department. The plasma samples were obtained in our blood sampling facility that receives both in- and outpatients. The highest plasma level of free glycerol observed was 300 µmol/L and in 99% of the investigated men the inclusion of plasma free glycerol in the measurement of plasma triglyceride cause a less than 10% false increase in plasma triglyceride. A weak positive correlation between the plasma levels of free glycerol and triglyceride was observed. When subdividing the cohort into mild and moderate hypertriglyceridemia, the positive correlation was only maintained in the moderate hypertriglyceridemia group that also demonstrated a 23% higher plasma glycerol level than men with mild hypertriglyceridemia. We conclude that even though glycerol blanking is relevant in rare occasions, then this study does not support providing such a measurement in our department. The positive correlation between free glycerol and triglyceride in this cohort likely reflects a shared association with metabolic dysregulation.

49 Effects of in-vitro digestibility in cannulated steers when supplemented different levels of glycerol

Abstract A study was conducted to evaluate effects of increasing concentration of food grade glycerol on rumen environment and nutrient digestibility. Three ruminally cannulated Jersey steers were used in this study. The study was conducted from March to May 2019. Experimental design was a 3x3 Latin square with a 2wk adjustment period followed by a 1wk collection period. Diet was coastal bermudagrass hay based. Different forage types were introduced in the incubation process to evaluate digestibility. Glycerol was administered once a day at 0, 15, or 20% of DMI (dry matter intake). dNDF (digestible NDF) and dDM (digestible dry matter) was determined using an ANKOM Daisy II incubator inoculated with 200g fresh rumen fluid and incubated for 12, 24, 48 and 72 h at 39°C. Each vessel contained ground forage samples in filter bags in triplicate. After incubation, filter bags were rinsed with cold water and dried for 24h in a 55°C forced air oven. Data were analyzed using the Proc MIXED procedure of SAS version 9.4. There was no difference dNDF in effect of different levels of glycerol between forage types by diet. But a numerical tendency was observed that dNDF was decreased at 20% inclusion rates in comparison to 0 and 15% inclusion of glycerol in the diet. Neither steer nor run was significantly different in the study. However as expected digestibility over time was significantly different (P < 0.001). A significant increase was observed in DMI with the increased levels of glycerol in the diet (P = 0.003), both the 15% and 20% levels of glycerol increased in DMI in comparison to the control (0%). It appears based on these study results that digestibility may be inhibited, as levels of dietary glycerol increase in the diet and more work needs to be done to find the optimal level of glycerol supplementation.

Effects of glycerol and thymol on physical, mechanical, and thermal properties of corn starch films

This study explores the preparation of corn starch (CS) films incorporated with glycerol, thymol, and combination of glycerol and thymol via solution casting technique. The resulting films were characterized in terms of structural changes, physical, optical, mechanical, and thermal properties. Results show that the presence of both glycerol and thymol in CS film increased the film thickness while reduced the moisture content, solubility, and transparency of the film. Fourier transform infrared spectroscopy revealed that intermolecular hydrogen bonding existed between CS, glycerol, and thymol. The presence of glycerol had more remarkable impact on tensile strength of CS films than that of thymol alone, while the combination of thymol and glycerol led to synergistic effects. Thermal degradation profiles of the films revealed the maximum degradation temperature of CS film with glycerol and thymol shifted to a higher temperature compared to other films indicating better thermal stability. In conclusion, the inclusion of glycerol and thymol led to improvement in overall performance of corn starch films.

Linseed and glycerol in forage diets effect methane production and rumen fermentation parameters in a Rusitec semi-continuos system

Context The use of oilseeds as a feed ingredient has been proposed to improve fatty acid profiles and reduce methane (CH4) emissions. Glycerol has been used as a common additive in ruminant feeding systems with variable effects on CH4 production. The effects of the combination of these ingredients remain unknown. Aims The aim of this study was to assess the effects of feeding linseed and increasing concentrations of glycerol in forage diets supplemented with corn grain on nutrient disappearance, CH4 production and rumen fermentation parameters. Methods Experimental diets were: control (70:30% hay:corn); linseed (70:15 :15% hay:corn:linseed); 5% glycerol (70:10:15:5% hay:corn:linseed:glycerol); 10% glycerol (70:5:15:10% hay:corn:linseed:glycerol). Diets were incubated in a completely randomised design with four replicates per treatment in a Rusitec apparatus for 15 days (10 days adaptation, 5 days sampling). Key results Total VFA production (VFA, mmol/day) was quadratically increased due to glycerol concentration in the diets (P = 0.009). Acetate:propionate (A:P) decreased by the inclusion of linseed (P < 0.001) and glycerol into the diets (P < 0.001). Linseed inclusion in the diet reduced CH4 production, mg/DM disappeared (P = 0.004) by up to 36%. These effects were not altered by the addition of glycerol into the diets. Ammonia nitrogen (NH3-N) production increased 2-fold in the linseed-added diets, but this effect was partially reverted by increasing glycerol concentrations in the diets (P < 0.001). Crude protein (CP) disappearance increased (P < 0.001) in the linseed added diets, with no effect of glycerol addition. Neutral detergent fibre (aNDFom; P = 0.005) disappearance was increased by the addition of linseed to the diet. Conclusions The use of linseed in ruminant diets reduces CH4 emissions but increases NH3-N production in a Rusitec system. This latter effect is partially reverted by glycerol inclusion in the diet. Propionate production increases with the inclusion of glycerol, but does not alter CH4 production. Including linseed increases the in vitro CP disappearance without affecting DM total disappearance. Implications Care should be taken with the use of oilseeds in ruminant diets as it can reduce CH4 emissions but may cause important increases in NH3 emissions. Inclusion of glycerol may partially overcome this latter issue.

Glicerina bruta ou glicerol na dieta de cordeiros: Uma metánalise – Desempenho, carcaça e carne

The intensification of biodiesel production inevitably generates the crude glycerine byproduct, which has little output for other uses mainly due to its purity. The inclusion of crude glycerin (GB) or glycerol (G) as an energy source, mainly as a corn substitute, may be a viable alternative in lamb finishing. In this sense, the objective of this study was to evaluate the levels of GB and G in the diet on lamb performance, carcass characteristics and meat quality through a metanalytic study. Twenty-four high impact articles were selected from research conducted in Brazil and abroad, involving 880 lambs distributed in 86 treatments. Data from both GB and G were grouped into levels. Based on the data contained in these articles were analyzed: initial live weight (PVI), slaughter live weight (PVA), dry matter intake (CMS), average daily gain (GMD), feed conversion (CA), carcass yield (RCQ), cold carcass yield (RCF), loin eye area (AOL), fat thickness (EG), saturated fatty acids (AGS), unsaturated (AGI), monounsaturated (AGMI), polyunsaturated (AGPI) , n6: n3 ratio, crude protein (CP), ether extract (EE), final pH and shear force in relation to control treatment (0% GB or G in MS). The obtained data were submitted to analysis of variance for linear and quadratic effect in each of the variables within all levels and, in the case of significance, regression analysis was performed. The performance, carcass characteristics and meat quality of lambs up to 36.0% of inclusion in the DM of GB and 32.4% of lambs diet did not have deleterious effect on them, and can be considered safe for human consumption. GB and G are presented as an alternative in the diet of finishing lambs, however, the strategy of use as energy substitute should come together with the study of the economic viability based on the price of corn, crude glycerin and demand of finished lambs in the region in question.

145 Digestibility of forages in ruminally cannulated Jersey steers supplemented with liquid glycerol on a wheat straw forage diet

Abstract The purpose of this study was to determine the impact of supplementation of glycerol at a rate of 15% of DMI on forage digestibility on a diet of mature wheat hay. Forages tested included bermuda hay, wheat hay, alfalfa hay, and sorghum sudan hay. Samples were ground through a 2mm screen and placed in Ankom forage in-situ bags. Samples were run in triplicate to reduce error and increase statistical significance. Two ruminally cannulated steers were used in a 2x2 Latin square design for the study with ad libitum access to wheat hay and water. Animals were housed in a dry lot pen for the study. Diets offered were Control = wheat hay and Treatment= control + glycerol at 15% of daily DMI. The study consisted of 2 three-week periods. Each period had a 2-week standardization followed by a 1-week test period. During the test period, forage bags were placed in each steer for 0 h, 48 h, 72 h, 96 h, and 144 h for fermentation. At the end of the incubation period, bags were collected and cold shocked to stop microbial digestion. The samples were then dried at 55°C and stored for later analysis for NDF. A significant impact on NDFdig by treatment (P < 0.0001) was observed. NDFdig was 59.2% w/ glycerol versus control at 49.13% overall. In addition, there was a significant difference between steers (P = 0.0001) on glycerol treatment (51.95% versus 66.45% NDFdig between steer A and B), indicating difference in ruminal population efficiency between individual animals. No significant difference (P = 0.98) between steers on the control treatment was observed. Implications of this study are the inclusion of dietary glycerol in the diet of ruminants on a low-quality forage diet may increase energy level and improve ruminal digestibility and animal response may be dependent on the unique ruminal environment of individual animals.

54 Digestibility of forages in ruminally cannulated Jersey steers supplemented with liquid glycerol on a wheat straw forage diet

Abstract The purpose of this study was to determine the impact of supplementation of glycerol at a rate of 15% of DMI on forage digestibility on a diet of mature wheat hay. Forages tested included bermuda hay, wheat hay, alfalfa hay, and sorghum sudan hay. Samples were ground through a 2mm screen and placed in Ankom forage in-situ bags. Samples were run in triplicate to reduce error and increase statistical significance. Two ruminally cannulated steers were used in a 2x2 Latin square design for the study with ad libitum access to wheat hay and water. Animals were housed in a dry lot pen for the study. Diets offered were Control = wheat hay and Treatment= control + glycerol at 15% of daily DMI. The study consisted of 2 three-week periods. Each period had a 2-week standardization followed by a 1-week test period. During the test period, forage bags were placed in each steer for 0 h, 48 h, 72 h, 96 h, and 144 h for fermentation. At the end of the incubation period, bags were collected and cold shocked to stop microbial digestion. The samples were then dried at 55°C and stored for later analysis for NDF. A significant impact on NDFdig by treatment (P < 0.0001) was observed. NDFdig was 59.2% w/ glycerol versus control at 49.13% overall. In addition, there was a significant difference between steers (P = 0.0001) on glycerol treatment (51.95% versus 66.45% NDFdig between steer A and B), indicating difference in ruminal population efficiency between individual animals. No significant difference (P = 0.98) between steers on the control treatment was observed. Implications of this study are the inclusion of dietary glycerol in the diet of ruminants on a low-quality forage diet may increase energy level and improve ruminal digestibility and animal response may be dependent on the unique ruminal environment of individual animals.

Improved Oxidative Biostability of Porous Shape Memory Polymers by Substituting Triethanolamine for Glycerol.

While many aromatic polyurethane systems suffer from poor hydrolytic stability, more recently proposed aliphatic systems are oxidatively-labile. The use of the renewable monomer glycerol as a more oxidatively-resistant moiety for inclusion in shape memory polymers (SMPs) is demonstrated here. Glycerol-containing SMPs and the amino alcohol control compositions are compared, with accelerated degradation testing displaying increased stability (time to complete mass loss) as a result of the inclusion of glycerol without sacrificing the shape memory, thermal transitions, or the ultralow density achieved with the control compositions. Gravimetric analysis in accelerated oxidative solution indicates that the control will undergo complete mass loss by approximately 18 days, while lower concentrations of glycerol will degrade fully by 30 days and higher concentrations will possess approximately 40% mass at the same time. In real time degradation analysis, high concentrations of glycerol SMPs have 96% mass remaining at 8 months with 88% gel fraction remaining that that time, compared to less than 50% mass for the control samples with 5% gelation. Mechanically, low glycerol-containing SMPs were not robust enough for testing at three months, while high glycerol concentrations displayed increased elastic moduli (133% of virgin materials) and 18% decreased strain to failure. The role of the secondary alcohol, as well as isocyanates, is presented as being a crucial component in controlling degradation; a free secondary alcohol can more rapidly undergo oxidation or dehydration to ultimately yield carboxylic acids, aldehydes, carbon dioxide, and alkenes. Understanding these pathways will improve the utility of medical devices through more precise control of property loss and patient risk management through reduced degradation.