Amount Of Glycerol Research Articles

Towards value-added chemicals: Technical and environmental life cycle assessment evaluation of different glycerol valorisation pathways

Biodiesel is acknowledged as the most appropriate biofuel to decarbonise the transport sector and combat climate change. The ever-increasing biodiesel production via transesterification results in large amount of glycerol (e.g., 10 kg of glycerol for every 100 kg of biodiesel). Converting glycerol into value-added goods is perceived to be a viable way to lower the high cost of producing biodiesel and expand its market share. The current study examines the technical and environmental aspects of bio-hydrogen, bio-syngas, acrolein, propylene glycol, epichlorohydrin, bio-methanol and bio-ethanol synthesis. CHEMCAD process simulation software was used to perform the modelling and simulation aspects considering a glycerol flowrate of 100 kg/h. The environmental study is based on primary and secondary data and is carried out using the Life Cycle Assessment methodology and the LCA for Experts software, using ReCiPe as the impact assessment method. The technical evaluation points towards glycerol conversion to propylene glycol and bio-methanol production as the best approaches given the relatively low energy requirements, increased purity (>97 wt%) and steadily growing product market. Bio-methanol exhibits the best environmental performance among all examined scenarios, providing the lowest impact in eight out of eleven categories studied while placing second in terms of FETP impact. Glycerol conversion towards propylene glycol seems as the second-best conversion route as it generates the lowest score in regards to GWP impact (0.31 kg CO2 eq./ kgproduct). Ultimately, the most effective methods for valorizing glycerol and improving the production of biodiesel by lowering the expenses related to its manufacturing are glycerol reforming toward bio-methanol and propylene glycol.

Bioinspired Synthesis of Novel Different Nanoparticles and its Utility in Biodiesel and Animals Applications

Because of its ability to speed up the reaction, the catalyst is critical to its success. Most catalysts are either homogeneous or heterogeneous. It has been shown that utilizing a heterogeneous catalyst, which is easier to remove from the product after the reaction has been finished. Because of the large surface area of the Nano-catalyst results in high catalytic efficiency. To enhance the performance of catalysts a range of various types of support materials have been used. SO42--ZnO and So42-/TiO active acid catalyst was prepared and characterized. ZnO nanoparticles catalyst synthesized by precipitation of zinc nitrate for comparison with supported catalyst. Sulphated zinc oxide (SO42--ZnO) and sulphated titania (SO42-/TiO) catalysts were synthesized using impregnation methods, to test their efficacy in biodiesel production. Various waste oils from different wastes such as mutton or beef tallow, chicken fat, and methanol are preferred to use during the esterification of waste animal fat oils using solid acid catalysts to produce biodiesel. Biodiesel synthesis generates a substantial amount of glycerol as a byproduct. Effect of optimum parameters such as temperature 60 degree centigrade (°C) shown 90% yield, time 1 hour resulted in 85% yield, catalyst dose 2wt% resulted in 80% yield, stirring speed 250rpm resulted in 80% yield, methanol to oil ratio12:1 resulted as 85.5% yield for transesterification of waste fat oil. It is valuable that the supported acid catalysts showed more yield than simply synthesized ZnO nanocatalyst similarly sulphated zinc oxide showed more FAME yield than sulphated titania.

Experimental study on the improvement of bamboo properties using amide polymer repair material based on the principle of self-energy dissipation

Traditional bamboo and wood components have different holes due to their own and external factors, and the appropriate hole repair technology is the key to improve the component's energy dissipation capacity. In this paper, based on the principle of in-situ free radical polymerization and hollow glass microsphere (HGM) reinforced polymer, PAM hydrogel (PAMHG) with better deformation recovery ability and PAM/HGM amide polymer (AP) with better mechanical properties were prepared. Based on the principle of self-energy dissipation of components, AP is used to improve the deformation capacity of hollow bamboo. The ratio of PAMHG and AP was optimized by single factor test and orthogonal test. The performance of AP was verified by bending test, SEM, energy consumption analysis，durability test and statistical analysis of small diameter round bamboo. The size of the bamboo sample is 250 mm (L)×15 mm (D)×2.5 mm (t), in accordance with LY/T 3347–2023 " Testing methods for physical and mechanical properties of small diameter round bamboo " (China). The results showed that an appropriate amount of glycerol could effectively improve the volume stability of the hydrogel. HGM effectively improved the strength of the polymer, and when the mass ratio of HGM/PAM was 0.48, the maximum compressive strength was 0.8 MPa, which was 2.4 times higher than that of the undoped HGM, and at this time, the optimal polymer ratios were 25 g of AM, 1 g of MBA, 0.01 g of APS, 2 g of TEA, 2 g of Carbomer SF-1, a volume ratio of 1:1 of glycerol/deionized water that the dispersion medium was 70 ml, and HGM was 12 g. The average energy dissipation of grouted bamboo at ultimate load was 2.02 times that of the control group, and the highest bending strength and elastic modulus were 128.01 MPa and 11.24 GPa, which were 41.39 % and 39.75 % higher than that of the control group, respectively. The SEM results revealed that the AP partially prepolymerized solution could infiltrate into the cells and pores of the bamboo material to achieve filling, bonding, as well as reinforcing the bamboo tissue. In addition, the durability test shows that AP has good resistance to environmental pressure. The results of this paper can provide a reference for the restoration materials of bamboo and wood components.

Preliminary study of synthesis and characterization of biodegradable avocado seed starch-chitosan plastic with glycerol plasticizer

Mechanical characteristics were studied for biodegradable plastics derived from avocado seed starch, emphasizing the influence of chitosan and glycerol. The extraction of starch from avocado seeds began with filtration. Different amounts of glycerol and chitosan were added to the extracted starch of up to 3% by weight. Because this method just uses distilled water instead of chemical chemicals, it was highly environmentally friendly. Tensile testing was done on the generated samples to assess the mechanical properties of this bioplastic; the results indicated that the samples’ elongation rates ranged from 21.9% to 134.7%. In spite of this, the bioplastic showed a comparatively low tensile strength, peaking at 3,381 MPa when chitosan-starch ratio was 2:1 and 1.5% glycerol was added.

Optimization and characterization of a dose-controllable orodispersible dexamethasone film for personalized medicine

Decadron® tablets are commercially available in 0.5 and 4 mg formulations, often requiring the use of multiple tablets or fractional doses when the required dosage is unavailable. This practice can lead to inaccuracies and handling difficulties associated with tablet splitting and crushing tablets into powder. This study aimed to develop an orodispersible dexamethasone film that would allow precise dose control and overcome these challenges. The film formulation was optimized by dissolving varying amounts of hypromellose, glycerol, and dexamethasone in ethanolic solutions. These solutions were cast and dried at different thicknesses. Statistical optimization using the design of experiments was used to determine the ideal film composition. The optimized films met pharmaceutical standards, with a mass variation ≦ 2 %, thickness variation ≦ 2.5 %, and disintegration time ≦ 20 s. The uniform distribution of dexamethasone within the film enabled easy content control based on the film area. Dissolution testing indicated that the dissolution behavior of the film formulation behaved similarly to commercial tablets for up to 90 min. In conclusion, the developed orodispersible film offers precise dexamethasone dose control and addresses the limitations of tablet splitting, positioning it as a promising candidate for personalized medicine applications.

Metabolomic differences between exanthematous drug eruption and infectious mononucleosis.

Exanthematous drug eruption and infectious mononucleosis (IM) are both exanthematous diseases. Current research on exanthematous drug eruption and IM mainly targets identifying these disorders, the resulting differences at the metabolism level have not yet been systematically analyzed. A total of 30 cases of exanthematous drug eruption and IM, 10 patients without exanthema and 10 healthy volunteers were enrolled, 3mL of fasting venous blood was collected, the serum metabolite content was detected by gas chromatography-mass spectrometry metabolomics. A total of 165 metabolites were identified, exhibiting significant differences in plasma metabolic trends between exanthematous drug eruption and IM, and pinpointed 28 potential biomarkers. Notable changes were seen in the metabolic activities of the pentose phosphate pathway (PPP), tricarboxylic acid cycle (TCA-cycle), and galactose metabolism, characterized by increased levels of gluconate, gluconolactone, glucose, galactaric acid, and mannose, along with decreased amounts of pyruvic acid, succinic acid, malic acid, and glycerol, indicating an impairment in the exanthematous drug eruption group's capacity to endure oxidative stress and regulate energy metabolism. In contrast to its medication without rash counterpart, the exanthematous drug eruption group's plasma displayed distinct metabolic routes, predominantly in the processing of arginine and proline, along with the TCA. This resulted in a marked reduction in urea levels and a rise in pyruvate, citrate, and ornithine, indicating hypoxic stress as the primary cause of these rashes. In contrast to the healthy control group, the IM group showed 26 potential biomarkers, marked by increased levels of ketoglutaric acid, malic acid, pyruvic acid, and oxoglutaric acid, and reduced amounts of glutamine, galacturonic acid, arachidonic acid, trimethylphosphonic acid ester, gluconolactone, and indole acetic acid. Mainly, the metabolic pathways included the TCA, breaking down alanine, aspartate and glutamate metabolism, and the processing of D-glutamine and D-glutamate metabolism, underscoring the body's crucial role in generating energy and inflammatory agents through the citric acid cycle. The comparison of serum metabolomic features of exanthematous drug eruptions and IM outlines a unique pattern closely related to the differences in the pathogenesis of these two exanthematous diseases.

Glycerol conversion and power generation in microbial fuel cells: insect exuviae biochar as electrodes and insect frass as biostimulants

Abstract Insects are a suitable raw material for refinement into biodiesel owing to their high fat content, but the refining process produces large amounts of insect waste and glycerol as a byproduct. Biochar electrodes were produced from insect waste for application in microbial fuel cells (MFCs), and experiments were performed to evaluate the electrochemical performance and glycerol conversion efficiency. The biochar was characterized by rich functional groups (O–H, O=C=O, C=C, C=O) and high microporosity, which favored the colonization of microbes. Among the electrode configurations considered, the optimal configuration was a biochar anode and carbon cloth cathode (B-MFC), showing the highest glycerol conversion efficiency (>95%). The B-MFC also exhibited the highest power density (122.3 mA/m3), 1.46-2.34 times that of the other MFCs tested. Adding Nitrogen-rich insect frass to the anode tank further stimulated microbial growth and increased power production, with the highest voltage output of 443.2 mV at 10 mg/L nitrogen concentration, 1.18 times higher than without addition. This study is the first to utilize insect exuviae as biochar electrodes in an MFC to solve the problems of excessive insect waste from biodiesel refinement and converting glycerol into a renewable energy source.

Impact of agar–glycerol ratios on the physicochemical properties of biodegradable seaweed films: A compositional study

To develop technology more applicable to industrial settings, this study aimed to produce agar-based bioplastic films using extrusion followed by hot compression. The research examined various amounts of glycerol incorporation as the plasticizer, which also facilitated the flowability of the extrusion process. These variations included agar–glycerol ratios of 75:25, 70:30, 65:35, 60:40, and 55:45 (% w/w). Moreover, the films underwent thorough testing to assess their physical, mechanical, chemical, water sensitivity, surface imaging, and biodegradability properties. The results showed that increasing the amount of glycerol in the agar film matrix generally made the films more sensitive to water, resulting in greater hydrophilicity. This change was primarily owing to the increased presence of hydroxyl groups. It also affected other characteristics, such as enhancing the film's stretchability and thermal stability. Furthermore, a decrease in film density was observed, leading to reduced tensile strength and barrier properties. Moreover, the higher glycerol content improved its surface wettability and the higher agar content accelerated the film's biodegradability rate. Microstructural examination using scanning electron microscopy and chemical analysis (FTIR) revealed a homogeneous mixture of agar and glycerol produced through the extrusion process. These findings demonstrate the potential of extrusion techniques for the large-scale production of agar-based bioplastics.

Hierarchical EMT structured zeolites as improved catalysts for glycerol dehydration

A fast and simple post-synthesis method for creating secondary mesoporosity in EMT zeolites was developed using an ammonium fluoride / cetyltrimethylammonium bromide (NH4F/CTAB) solution at low temperature with ultrasound irradiation. This strategy is shown to be highly effective for producing hierarchical EMT structured zeolites through the etching of both Si and Al species. The catalytic performance of these materials were assessed using glycerol dehydration as a reaction test, which is in addition a relevant reaction due to the high amounts of glycerol generated as a by-product of biodiesel production. The resulting hierarchical EMT structured zeolites exhibited improved catalytic activity and high selectivity towards acrolein (around 80 %). This innovative approach creates new opportunities for using hierarchical EMT structured zeolites in processes related with biodiesel manufacture.

Purification of crude glycerol derived from biodiesel production process using ceramic membranes: Experimental studies and modeling of flux behavior

Large-scale biodiesel production generates large quantities of glycerol with high impurities levels, and new purification processes are needed to add value to this by-product of biodiesel production. Thus, this study evaluated the application of ceramic membranes for glycerol purification from biodiesel production and the influence of the mean pore diameter of the membrane, pressure, temperature, and the addition of acidified water to the mixture to be purified. The experiments were carried out in a tangential filtration module with ceramic membranes of 5 kDa, 20 kDa, 0.05 μm, and 0.2 μm, varying the pressure by 1, 2, and 3 bar and the temperature by 25, 40, and 60 °C. The results showed that increasing the pressure, average pore diameter and temperature caused an increase in the permeate flux. Furthermore, adding acidified water increased permeate fluxes and glycerol concentrations for all membranes and pressures used. A higher glycerol content (91.13 %) was obtained with the 5 kDa membrane at 3 bar and 60 °C. The traditional fouling mechanism models failed to fit most of the experimental data. On the other hand, the proposed generalized model adequately predicted the experimental permeate flux data for the different types of fouling mechanisms observed.

Purification of Crude Glycerol Derived from Hydrogenated Cottonseed and Its Use in Confectionary Products

Abstract Glycerol is a versatile substance used in food, beverages, cosmetics, and technical applications. It can be derived from fats and oils through 4 different reactions, including: transesterification, directed hydrogenation, hydrolysis, and saponification. Glycerol derived from fat hydrolysis yields superior quality and quantity when compared to saponification. The resulting glycerol water is purified and concentrated through evaporation to yield crude glycerol with a concentration of 86-88%. Two distinct methods are recognized for further improving quality of glycerol: distillation, and the purification of glycerol water through the ion exchange process followed by evaporation. The goal of this research was to improve the purification process of glycerol, for obtaining premium-quality glycerol without the need for distillation, through the utilization of cations. Several combinations of activated carbon and clay were tested, and it was determined that a combination of 70:30 yielded the optimal results, considering the amount of glycerol and ash content. Technological parameters such as reaction durations, pH, and process temperatures were investigated, and it was discovered that the appropriate combination was a process duration of more than 40 minutes, a pH value of 2, and a temperature of 70°C. Besides, it was also determined that the concentration and quality of glycerol derived from cottonseed oil can be enhanced through distillation or purification with cationite. Moreover, different concentrations of glycerol on the elaboration of gingerbread were tested, and the conclusion is that adding 5% of the resulting glycerol to the gingerbread recipe could ensure better preservation of its quality during its shelf life.

Effect of the glycerol dispersant on the structure, electrical transport and magnetoresistive properties of La0.67Ca0.33MnO3 ceramics prepared by the sol-gel routine

In this paper, the sol-gel technique is employed to synthesize polycrystalline La0.67Ca0.33MnO3 (LCMO) ceramics, where methanol is chosen as the solvent. The crystal structure, morphology, as well as electrical and magnetoresistive properties were examined. Moreover, the effect of amount of the dispersant glycerol on the properties of LCMO ceramics is studied. X-ray diffraction (XRD) results showed that all samples crystallized in single phases with orthogonal perovskite structure (pnma space group), without any detectable impurity phases. Results reveal that the grain size of LCMO ceramics exhibits an initial increase followed by a decrease, accompanied by a similar behavior in the temperature coefficient of resistance (TCR) and magnetoresistance (MR). When the volume ratio of glycerol and methanol reached 2 %, the grain size is determined to be 7.30 μm, with TCR value of 25.02 % K−1 at T= 263.2 K, and MR value recorded at 55.40 %. The study elucidates the influence of glycerol on LCMO polycrystalline ceramics and optimize the fabrication process, thereby improve the electric transport property and magnetoresistance.

Evaluation of Chemical and Physical Triggers for Enhanced Photosynthetic Glycerol Production in Different Dunaliella Isolates.

The salt-tolerant marine microalgae Dunaliella tertiolecta is reported to generate significant amounts of intracellular glycerol as an osmoprotectant under high salt conditions. This study highlights the phylogenetic distribution and comparative glycerol biosynthesis of seven new Dunaliella isolates compared to a D. tertiolecta reference strain. Phylogenetic analysis indicates that all Dunaliella isolates are newly discovered and do not relate to the D. tertiolecta reference. Several studies have identified light color and intensity and salt concentration alone as the most inducing factors impacting glycerol productivity. This study aims to optimize glycerol production by investigating these described factors singularly and in combination to improve the glycerol product titer. Glycerol production data indicate that cultivation with white light of an intensity between 500 and 2000 μmol m-2 s-1 as opposed to 100 μmol m-2 s-1 achieves higher biomass and thereby higher glycerol titers for all our tested Dunaliella strains. Moreover, applying higher light intensity in a cultivation of 1.5 M NaCl and an increase to 3 M NaCl resulted in hyperosmotic stress conditions, providing the highest glycerol titer. Under these optimal light intensity and salt conditions, the glycerol titer of D. tertiolecta could be doubled to 0.79 mg mL-1 in comparison to 100 μmol m-2 s-1 and salt stress to 2 M NaCl, and was higher compared to singularly optimized conditions. Furthermore, under the same conditions, glycerol extracts from new Dunaliella isolates did provide up to 0.94 mg mL-1. This highly pure algae-glycerol obtained under optimal production conditions can find widespread applications, e.g., in the pharmaceutical industry or the production of sustainable carbon fibers.

Synthesis and Characterization of Triticale Starch-Based Hydrogel for pH Responsive Controlled Diffusion.

Considering the FAO perspectives for agriculture toward 2030, many natural sources will be no longer profitable for the synthesis of many biomaterials. Triticale (X Triticosecale Wittmack) is a cereal crop synthesized to withstand those marginal conditions; however, it is primarily used as fodder worldwide. We reported for the first time the synthesis of a natural anionic hydrogel with gastrointestinal pH stimulus-response as a new alternative of smart material, based on Eronga triticale starch as sustainable biomass, using citrate (pK a ∼3.1, 4.7, and 6.4) as cross-linking agent. The scanning electron microscopy and X-ray diffraction exhibited A and B-type starch granules, and semicrystallinity A-type. The presence of the anionic sensing group (COOH) was verified by infrared spectroscopy, the interactions by hydrogen bonds between starch and glycerol and esterification between starch and citric acid were identified by 1H NMR spectra, and through thermal analysis hydrogels exhibited four endothermic curves (179-319 °C, ∼0.711-39 kJ/mol E a). The results showed that the slight addition of glycerol increases the thermal stability, but a higher amount of glycerol decreases the intermolecular forces affecting the thermal stability contrary, the mechanical properties could be benefited. The rheological analyses showed viscoelastic tendency (G' > G″) with high stability (Tanδ < 1) in frequency, time, and strain sweeps. Gastrointestinal pH sensitivity (∼2-7.8) was verified (α ≤ 0.01) following Fick's diffusive parameters, which resulted in a tendency to gradually release BSA with increasing pH ∼3-7 by anomalous and case-II diffusion, showing greater release at pH ∼7.8/3.5 h (80-96%). We aim to expand the biomaterials area focusing on triticale starch due to its limited reported investigations, low-cost, green modification, and its rheological performance as plastic.

Effects of exoskeleton-assisted walking on bowel function in motor-complete spinal cord injury patients: involvement of the brain-gut axis, a pilot study.

Evidence has demonstrated that exoskeleton robots can improve intestinal function in patients with spinal cord injury (SCI). However, the underlying mechanisms remain unelucidated. This study investigated the effects of exoskeleton-assisted walking (EAW) on intestinal function and intestinal flora structure in T2-L1 motor complete paraplegia patients. The results showed that five participants in the EAW group and three in the conventional group reported improvements in at least one bowel management index, including an increased frequency of bowel evacuations, less time spent on bowel management per day, and less external assistance (manual digital stimulation, medication, and enema usage). After 8 weeks of training, the amount of glycerol used in the EAW group decreased significantly (p <0.05). The EAW group showed an increasing trend in the neurogenic bowel dysfunction (NBD) score after 8 weeks of training, while the conventional group showed a worsening trend. Patients who received the EAW intervention exhibited a decreased abundance of Bacteroidetes and Verrucomicrobia, while Firmicutes, Proteobacteria, and Actinobacteria were upregulated. In addition, there were decreases in the abundances of Bacteroides, Prevotella, Parabacteroides, Akkermansia, Blautia, Ruminococcus 2, and Megamonas. In contrast, Ruminococcus 1, Ruminococcaceae UCG002, Faecalibacterium, Dialister, Ralstonia, Escherichia-Shigella, and Bifidobacterium showed upregulation among the top 15 genera. The abundance of Ralstonia was significantly higher in the EAW group than in the conventional group, and Dialister increased significantly in EAW individuals at 8 weeks. This study suggests that EAW can improve intestinal function of SCI patients in a limited way, and may be associated with changes in the abundance of intestinal flora, especially an increase in beneficial bacteria. In the future, we need to further understand the changes in microbial groups caused by EAW training and all related impact mechanisms, especially intestinal flora metabolites. Clinical trial registration: https://www.chictr.org.cn/.

Synthesis of cellulose nano fiber from palmyrah fruit fiber and its applicability as a reinforcement agent on starch based biodegradable film

The global trend in packaging is shifting towards environmentally friendly, natural materials that decompose easily. Among the bio-based packaging materials, starch is a renewable, biodegradable, bio-compatible, and easily accessible source. However, starch-based biodegradable films depict weak mechanical properties compared with synthetic polymers. This problem can be solved by incorporating reinforcement fillers into the starch matrix. Palmyrah fruit (Borassus flabellifer L.) waste can be a good source to obtain fillers due to its high cellulose content. The aim of the study was to investigate the reinforcement of starch-based biodegradable films with the incorporation of pure cellulose nanofiber (CNF) obtained from palmyrah fruit fiber (PFF). Chemical treatments such as alkaline treatment (4% NaOH), bleaching [1% Ca(OCl)2], and acid hydrolysis (10 moldm-3 H2SO4) were done successively to obtain pure CNF from PFF. CNF was characterized using FTIR and particle size distribution (PSD) was analyzed by granulometry. The yield of CNF from PFF was 37.890±0.008 %. The results of FTIR depicted CNF was synthesized successfully. Five different biodegradable films were prepared by varying the amount of palmyrah tuber starch (4.5-2.5 w/w %) and CNF (0.0-2.0 w/w %) while the amount of glycerin (1.5 w/w %) and gelatin (1 w/w %) were kept constant. PSD results revealed that nano-sized CNF (10-100 nm) was synthesized successfully. The optimized film was selected based on the tensile strength and low water vapor transmission rate. Optimized film formulation, with palmyra tuber starch (3 w/w %) and CNF (1.5 w/w %) showed desirable physical, mechanical and optical properties, including the thickness, moisture content, water vapor transmission rate, water uptake, transparency at 600 nm, water activity, water solubility and tensile strength of 0.192±0.004 mm, 11.07±0.04 %, 3.870±0.005 g/m2.day, 22.34±0.05 %, 3.97±0.01 %, 0.440±0.001, 51.68±0.140 % and 9.55 MPa respectively. All films showed excellent soil biodegradability within two weeks. In conclusion, palmyra fruit CNF can be effectively used to reinforce starch-based biodegradable packaging films.

Characterization of Biodegradable Films from Raw Seaweed (Kappaphycus Alvarezii) and Glycerol

Abstract To reduce the use of plastic, innovation is needed to make packaging materials that are environmentally friendly and easy to be degraded. As the main ingredient of this packaging material should be organic materials that are easily obtained. One of the organic materials is seaweed (Kappaphycus Alvarezii) which can be used as raw material for making biodegradable packaging and combined with glycerol. Biodegradable films with nine combinations of seaweed and glycerol were developed to gain the best composition. The yields of these combinations were tested on their tensile strength, elongation, Modulus Young, Water Vapor Permeability, and biodegradability. The Tensile Strength value of the film with 1 gram seaweed and 1 gram glycerol (S1G1) was the highest (22.366±2.148017 MPa), The elongations values of the films with 1.5 g glycerol and 2 g seaweed (18.99217±2.442663%) were highest significantly. The water vapor permeability (WVP) and the thickness of the composite films increased due to the increase of seaweed and glycerol amounts respectively. The biodegradability increased if the seaweed amounts decreased, but it increased if the glycerol amounts increased as well.

The Role of the Heterogeneous Catalyst to Produce Solketal from Biodiesel Waste: The Key to Achieve Efficiency.

The valorization of the large amount of crude glycerol formed from the biodiesel industry is of primordial necessity. One possible direction with high interest to the biorefinery sector is the production of fuel additives such as solketal, through the acetalization of glycerol with acetone. This is a chemical process that conciliates high sustainability and economic interest, since solketal contributes to the fulfillment of a Circular Economy Model through its use in biodiesel blends. The key to guarantee high efficiency and high sustainability for solketal production is the use of recovery and recyclable heterogeneous catalysts. Reported works indicate that high yields are attributed to catalyst acidity, mainly the ones containing Brönsted acidic sites. On the other hand, the catalyst stability and its recycling capacity are completely dependent of the support material and the acidic sites incorporation methodology. This review intends to conciliate the information spread on this topic and indicate the most assertive strategies to achieve high solketal production in short reaction time during various reaction cycles.

Towards scalable and degradable bioplastic films from Moringa oleifera gum/poly(vinyl alcohol) as packaging material

The use of plant gum-based biodegradable bioplastic films as a packaging material is limited due to their poor physicochemical properties. However, combining plant gum with synthetic degradable polymer and some additives can improve these properties. Keeping in view, the present study aimed to synthesize a series of bioplastic films using Moringa oleifera gum, polyvinyl alcohol, glycerol, and citric acid via thermal treatment followed by a solution casting method. The films were characterized using analytical techniques such as FTIR, XRD, SEM, AFM, TGA, and DSC. The study examined properties such as water sensitivity, gas barrier attributes, tensile strength, the shelf life of food, and biodegradability. The films containing higher citric acid amounts showed appreciable %elongation without compromising tensile strength, good oxygen barrier properties, and biodegradation rates (>95%). Varying the amounts of glycerol and citric acid in the films broadened their physicochemical properties ranging from hydrophilicity to hydrophobicity and rigidity to flexibility. As all the films were synthesized using economical and environmentally safe materials, and showed better physicochemical and barrier properties, this study suggests that these bioplastic films can prove to be a potential alternative for various packaging applications.

Three-channel fluorescent probe for real-time monitoring mitochondrial viscosity during mitophagy and visualizing ONOO-/SO2 in rheumatoid arthritis mice

ONOO- and SO2 are important microenvironment parameters in organisms, the intracellular levels of ONOO- and SO2 are abnormal in rheumatoid arthritis (RA) mice. Mitophagy plays a key role in maintaining mitochondrial quality and quantity, and viscosity monitoring is a crucial aspect of real-time visualization of mitophagy. Therefore, a mitochondria-targeting three-channel fluorescent probe HCPVP was first developed for the detection of ONOO-/SO2 and viscosity. HCPVP can sensitively detect ONOO- (514 nm) and SO2 (674 nm) change with different channels, meanwhile display turn-on fluorescence at 678 nm as the amount of glycerol increased. The fluorescence imaging of cells showed that HCPVP was able to better target mitochondria, monitor ONOO-/SO2 changes, and visualize the mitophagy process. HCPVP has been successfully used for monitoring ONOO- and SO2 in RA mice model, providing the early image of RA with the aid of the potential biomarkers ONOO- and SO2. More importantly, HCPVP could evaluate the response of the RA treatment with impressive results, which held the potential for assessing treatment and drug screening for RA.