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The high starch content and cost-effectiveness of cassava make it an attractive adjunct in beer brewing, with the fine structure of starch playing a crucial role in determining the composition of fermentable sugars (FS) and overall beer quality. This study investigated the effect of extrusion-induced changes in the starch structure of cassava flour on the FS profile of the wort and, consequently, on the quality attributes of cassava beer. The findings revealed that the shear stress during extrusion significantly reduced the molecular weight to 1.20 × 105g/mol and the branching degree of amylopectin. Simultaneously, there was an increase in the concentrations of short- and intermediate- chain amylose by 5.61% and 42.72%, respectively. These structural changes enhanced the enzymatic hydrolysis of extruded cassava flour (ECF), resulting in a higher total fermentable sugars content (22.00g/100 mL) in the ECF wort, predominantly composed of maltose and glucose. Furthermore, the altered FS profile led to an increased production of higher alcohols and esters in extruded cassava beer (ECB), particularly noted for the elevation of 2-phenylethyl alcohol levels, which imparted a distinctive rose aroma to the ECB. Consequently, the sensory profile of ECB showed significant improvement. This study offers critical insight into optimizing cassava beer quality and broadens the potential applications of cassava flour in the brewing industry.

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The processing characteristics of yogurt are closely related to the composition and arrangement of exopolysaccharides (EPS) in lactic acid bacteria (LAB). To fully understand and develop the functional properties of EPS and to study the effect of EPS molecular weight on yogurt and its mechanism, the physicochemical properties of high molecular weight EPS-LH43, medium molecular weight EPS-LH13, and low molecular weight EPS-LH23, as well as the gel properties and protein conformation of yogurt, were determined and analyzed in this experiment. The results indicate that EPS-LH43 and EPS-LH13 are both composed of mannose, rhamnose, galacturonic acid, glucose, and galactose. EPS-LH23 is composed of mannose, galacturonic acid, glucose, and galactose. Their Number-average Molecular Weight is 5.21 × 106 Da, 2.39 × 106 Da and 3.76 × 105 Da, respectively. In addition, all three types of EPS have good thermal stability and can improve the stability of casein. In addition, the analysis of the texture, particle size, potential, water holding capacity, rheology, low field nuclear magnetic resonance, microstructure, and flavor characteristics of yogurt confirmed the relationship between the molecular weight of LAB EPS and the gel properties of yogurt. Fluorescence spectrophotometer and circular dichroism analysis indicate that the different molecular weights of LAB EPS have different effects on protein structure, which is an intrinsic factor leading to significant differences in the gel properties of the three types of fermented milk. These findings provide new references for enhancing the understanding of the structure-activity relationship of EPS and indicate that EPS-LH43 can be used to improve the gel properties of dairy products.

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We have described a new route for the preparation of partially methylated polygalacturonic acid containing hydrolyzed (acidic) and unhydrolyzed (methyl esterified) carboxylate groups in a ratio of 1:1 (PGA, compound 1), and one of its basic FeIII-salts (compound 2) with a ~1:2 FeIII:GA stoichiometry (GA means galacturonic acid and methylated galacturonic acid units). The partially hydrolyzed pectin was transformed into compound 1 with the use of double ion exchange with a strongly acidic macroreticular sulfonated styrene-divinylbenzene copolymer as a hydrogen ion source. The reaction of compound 1 with FeCl3 resulted in compound 2. Compound 2 has a polymeric nature and contains binuclear FeIII(µ-O)(µ-OH)FeIII core units with two kinds of distorted octahedral iron geometries. The salt-forming acidic and methylated GA units of compound 1 are coordinated to FeIII centers in asymmetric bidentate-chelating and -bridging (via C=O group and glycosidic oxygen) modes, respectively. Two kinds of outer-sphere chloride anions were also detected by XPS in various chemical environments fixed by different sets of hydrogen bonds. We also observed a partial reduction of FeIII into FeII due to the ring-opening of the chain-end GA units of compound 1. This reaction provides a new route to determine the number of chain-ends in compound 2, and with the use of the number of GA units calculated from charge neutrality, the average length of these chains and the average molecular weight were also determined. The average molecular weight of the partially methylated polygalacturonic acid used in the industrial-scale production of commercial anti-anemic iron-polygalacturonate agents was ~50,000 g/mol. Compound 2 was also characterized by IR, Mössbauer, and X-ray photoelectron spectroscopy, and magnetic susceptibility measurements. These results on the structure and average molecular weight of basic iron(III) polygalacturonate provide a tool to design Fe-PGA complexes with tuned iron-releasing properties.

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Utilizing the copolymerization modification of dimethyl diallyl ammonium chloride (DMDAAC), the high positive charge density of the copolymer could be maintained, thereby facilitating the deficiency of its monomer in the application. In this paper, poly (DMDAAC-co-DAMBAC) (9:1) was synthesized with an aqueous polymerization method using DMDAAC and methyl benzyl diallyl ammonium chloride (DAMBAC) as monomers and 2,2'-azobis [2-methylpropionamidine] dihydrochloride (V50) as an initiator. Targeted to the product's weight-average relative molecular mass (Mw), the response surface methodology (RSM) was used to optimize the preparation process. The optimal process conditions were obtained as follows: w (M) = 80.0%, m (V50):m (M) = 0.00700%, m (Na4EDTA):m (M) = 0.00350%, T1 = 50.0 °C, T2 = 60.0 °C, and T3 = 72.5 °C. The intrinsic viscosity ([η]) of the product was 1.780 dL/g, and the corresponding double bond conversion (Conv.) was 90.25 %. Poly (DMDAAC-co-DAMBAC) (9:1) revealed a highest Mw of 5.637 × 105, together with the polydispersity index d (Mw/Mn) as 1.464. For the demulsification performance of simulated crude oil O/W emulsions, the demulsification rate of poly (DMDAAC-co-DAMBAC) (9:1) could reach 97.73%. Our study has illustrated that the copolymerization of DMDAAC and a small amount of DAMBAC with poor reactivity could significantly improve the relative molecular weight of the polymer, enhance its lipophilicity, and thus the application scope of the polymer.

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Polyvinyl chloride is used in the manufacturing of a wide range of products, but it is susceptible to degradation if exposed to high temperatures and sunlight. There is therefore a need to continuously explore the design, synthesis, and application of new and improved additives to reduce the photodegradation of polyvinyl chloride in harsh environments and for outdoor applications. This research investigates the use of new norfloxacin-tin complexes as additives to inhibit the photodegradation of polyvinyl chloride to make it last longer. Reactions between norfloxacin and substituted tin chlorides, in different molar ratios and in methanol under reflux conditions, gave the corresponding organotin complexes in high yields. The chemical structures of the synthesized complexes were established, and their effect on the photodegradation of polyvinyl chloride due to ultraviolet-visible irradiation was investigated. Norfloxacin-tin complexes were added to polyvinyl chloride at very low concentrations and homogenous thin films were made. The films were irradiated for a period of up to 300 h, and the damage that occurred was assessed using infrared spectroscopy, polymeric materials weight loss, depression in molecular weight, and surface inspection. The degree of photodegradation in the polymeric materials was much less in the blends containing norfloxacin-tin complexes compared to the case where no additives were used. The use of the additives leads to a reduction in photodegradation (e.g., a reduction in the formation of short-chain polymeric fragments, weight loss, average molecular weight depletion, and roughness factor) of irradiated polyvinyl chloride. The norfloxacin-tin complexes contain aromatic moieties (aryl and heterocycle), heteroatoms (nitrogen, oxygen, and fluorine), and an acidic center (tin atom). Therefore, they act as efficient photostabilizers by absorbing the ultraviolet radiation and scavenging hydrogen chloride, peroxides, and radical species, thereby slowing the photodegradation of polyvinyl chloride.

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A water-soluble heteropolysaccharide (SGP2-1) was purified from Suillus granulatus fruiting bodies by anion-exchange chromatography and gel permeation chromatography. The structural characteristics were analyzed by high-performance gel permeation chromatography, high-performance liquid chromatography, Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectroscopy. The immunostimulatory activity was investigated using RAW 264.7 macrophages. Results showed that SGP2-1 with weight average molecular weight of 150.75 kDa was composed of mannose, glucose, and xylose. The backbone of SGP2-1 was mainly composed of â†’ 4)-α-Glcp-(1→, and the terminal group α-d-Glcp â†’ was linked to the main chain by O-6 position. SGP2-1 could significantly enhance pinocytic capacity, reactive oxygen species production, and cytokines secretion. SGP2-1 exerted immunomodulatory effects through interacting with toll-like receptor 2, and activating mitogen-activated protein kinase, phosphatidylinositol-3-kinase/protein kinase B, and nuclear factor-kappa B signaling pathways. These findings indicated that SGP2-1 could be explored as a potential immunomodulatory agent for application in functional foods.

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Suture is an important part of surgery, and wounds closing after surgery remains a challenge for postoperative care. Currently, silk, linen fiber, and cotton are available in the market as non-absorbable suture biomaterials. So, there is an urgent need to develop a novel suture with advantageous characteristics compared to the ones available on the market. In present study, a series of ultra-high molecular weight chitosan with different DD and MV were prepared from squid cartilage by alkaline treatment and ultrasonic degradation. The corresponding chitosan monofilaments were prepared by a wet spinning process and were characterized as sutures. The effects of the DD and MV of chitosan on the properties of its monofilament were studied, including surface morphology, mechanical property, swelling ratio, ash content, in vitro enzymatic degradation, and in vitro cytotoxicity. According to the results, AS-85 was chosen to be the best suitable as an absorbable surgical suture, which was spun from squid cartilage chitosan with DD~85% and MV~1.2 × 106. The outcome of the present study might derive tremendous possibilities for the utilization of squid cartilage ß-chitin for biomedical applications.

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Dissolved organic matter (DOM) in soil is a key factor affecting the bioavailability of heavy metals, but very few studies have focused on the role of DOM in the use of soil amendments to mitigate heavy metal accumulation in crops. Here, eleven materials were added to cadmium (Cd)-contaminated paddy soil in greenhouse pot trials; rice was grown and harvested, the chemodiversity of post-harvest soil DOM was characterized using Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry, and the specific associations between soil DOM traits and water-extractable soil Cd concentration were identified at the molecular level. The results showed that the endogenous release caused by altering soil pH had a greater effect on soil DOM concentration than did the exogenous chemical input due to the application of organic amendments, which in turn contributed to the chemodiversity of DOM. After one season of rice cultivation, soil DOM molecules were mainly dominated by relatively low molecular weight heteroatom-free lignins. C/N, C/H ratios of organic materials influenced DOM molecular fingerprint patterns, and soil pH and redox potential were the main driving forces affecting the chemodiversity of DOM. Furthermore, the low molecular weight, high saturation, low aromaticity, and heteroatom-free DOM molecules are more likely to dissolve Cd from the soil solid phase, thus increasing the potential risk of Cd to the environment. The results provide critical information about amendments-induced changes in DOM chemodiversity and will inform the selection of appropriate soil amendments.

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Blends of poly(butylene adipate-co-terephthalate) (PBAT) and polylactide (PLA) have attracted the attention of academia and industry as a sustainable material. Unfortunately, this combination results in problems related to poor miscibility on the molecular level. This study mainly aims to determine the influence of molecular weights on the miscibility of PBAT/PLA blends. First, polymers with various molecular weights were obtained by the hydrolysis of PBAT and methanolysis of PLA. Second, the two components were solution-blended with different molecular weights and weight ratios. Third, each blend was heated to the molten state and subsequently stored at room temperature. Finally, the samples were tested using DSC and SEM. The thermal analysis indicated that the difference in glass transition temperature between both components decreased from about 91 °C to 57 °C and 0 °C, as the number-average molecular weights (Mn) decreased from 52/127 to 9.4/9 and 6.3/6.6 kg/mol. Moreover, the morphology changed from phase-separated with dispersed large particles gradually to uniform and homogeneous. This experimental work validated the trends predicted in the previous study, namely that PBAT/PLA blends changed the state from immiscible to partially miscible to fully miscible with decreasing Mn values. Moreover, we discussed the influencing factors such as weight ratio, temperature, and molecular structure on the miscibility. Based on the results, this work contributes to developing partially miscible and compatible blends without additives.

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Knowledge of aromatic compounds in petroleum samples is of paramount interest from processing and environmental viewpoints. Considering the complexity of such samples, a selective analytical strategy viz. aromatic specific size exclusion chromatographic methodology using amino-bonded silica phase, was adopted to obtain the average molecular weights of distilled cuts, residue and the corresponding crude oil. The method was found to be suitable from middle distillates up to the residue. It was found that the increase in boiling temperature of distilled cuts was reflected in an increase in high molecular weight aromatic species. The increase in the molecular weight of aromatic species is linked to the increase in alkylation as verified by studying the elution pattern of alkylated aromatic compounds. The accuracy of the molecular weights obtained from the size exclusion chromatographic method depends on the elution profile of aromatic species in petroleum samples. It was found that the size and shape of the parent aromatic compounds negatively influence the size exclusion elution profile. However, such influence can be assumed to be negligible as all the aromatic species of each distilled cut, residue, and crude oil eluted in the permeation zone of the chromatogram. This method has the potential to be used in the second dimension of a 2D-LC method where the aromatic compounds are separated based on the size (or alkylation). The first dimension will separate compounds based on the number of aromatic rings, thereby eliminating the interference of parent aromatic compounds of different sizes in the total elution profile.

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Pulmonary administration route has been extensively exploited for the treatment of local lung diseases such as asthma, chronic obstructive pulmonary diseases and respiratory infections, and systemic diseases such as diabetes. Most inhaled medicines could be cleared rapidly from the lungs and their therapeutic effects are transit. The inhaled medicines with extended pulmonary exposure may not only improve the patient compliance by reducing the frequency of drug administration, but also enhance the clinical benefits to the patients with improved therapeutic outcomes. This article systematically reviews the physical and chemical strategies to extend the pulmonary exposure of the inhaled medicines. It starts with an introduction of various physiological and pathophysiological barriers for designing inhaled medicines with extended lung exposure, which is followed by recent advances in various strategies to overcome these barriers. Finally, the applications of the inhaled medicines with extended lung exposure for the treatment of various diseases and the safety concerns associated to various strategies to extend the pulmonary exposure of the inhaled medicines are summarized.

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Ultrasound-assisted extraction (UAE) of polyphenols from the brown seaweeds Ascophyllum nodosum leaves a solid phase where alginates can be extracted. This study characterizes alginates extracted after the UAE process, with and without an intermediate drying stage at different temperatures (50 and 90 °C) producing sequentially two bioactive compounds from a unique raw material. FT-IR and 1H NMR analyses showed the high purity of alginates with features in the range of commercial alginates. Drying at high temperature decreased average block length and viscosity average molecular weight (Mv) of alginate from 428 to 133 kg/mol. Steady-shear curves (shear-thinning behaviour) and viscoelasticity (liquid like character) features depended clearly on Mv. Solutions of alginates with high Mv were more viscous and the elastic character was more relevant. Cox-Merz rule was only accomplished within the semi-dilute regimes of alginate concentration. Tested process conditions allow the production of alginates with different properties.

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(1) Background: Household humidifier disinfectant (HD) brands containing polyhexamethylene guanidine (PHMG) have been found to cause the most HD-associated lung injuries (HDLIs) in the Republic of Korea. Nevertheless, no study has attempted to characterize the potential association of the health effects, including HDLI, with the physicochemical properties of PHMG dissolved in different HD brands. This study aimed to characterize the molecular weight (MW) distribution, the number-average molecular weight (Mn), the weight-average molecular weight (Mw), and the structural types of PHMG used in HD products. (2) Methods: Quantitative measurements were made using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). The Mn, Mw, and MW distributions were compared among various HD products. (3) Results: The mean Mn and Mw were 542.4 g/mol (range: 403.0-692.2 g/mol) and 560.7 g/mol (range: 424.0-714.70 g/mol), respectively. The degree of PHMG oligomerization ranged from 3 to 7. The MW distribution of PHMG indicated oligomeric compounds regardless of the HD brands. (4) Conclusions: Based on the molecular weight distribution, the average molecular weight of PHMG, and the degree of polymerization, the PHMG collected from HDLI victims could be regarded as an oligomer. PHMG, as used in household humidifiers, should not be exempted from toxic chemical registration as a polymer. Further study is necessary to examine the association of PHMG oligomeric compounds and respiratory health effects, including HDLI.

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Comparison analysis of vehicle headlamp lens fragments can help establish links between the relevant vehicle with crime scenes or provide useful information to search the related vehicles. Headlamp lenses are mainly made of polycarbonate with very few signature additives, which makes them difficult to be discriminated by commonplace examination methods of infrared spectroscopy and scanning electron microscope coupled with energy dispersive X-ray spectroscopy. In this study, molecular weights (Mw) and the polydispersity index (PDI) value of 50 vehicle headlamp lens fragments from different vehicles were measured by gel permeation chromatography, and Hotelling's T2 statistical method was applied to facilitate interpretation of the data. Among the total C 50 2 = 1225 pairs of comparisons between 50 samples, 62 pairs cannot be distinguished, resulting in a discrimination rate of 94.94%. It suggested that the method of gel permeation chromatography and Hotelling's T2 statistical analysis were powerful to make further discrimination between plastic vehicle headlamp lens fragments.

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As the next step in the translation of vascular tissue engineering, this study uniquely combines transcatheter delivery and in situ tissue regeneration using a novel bioresorbable electrospun polymer graft that can be implanted minimally invasively. Once delivered inside a small-diameter vessel, the electrospun microstructure supports the vessel wall, facilitates cellular infiltration, and guides organized tissue formation.

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Hyaluronan (HA) has been widely used in medicines, cosmetics and supplements for health and beauty maintenance. Oral administration is the most desirable and convenient means for consumers. The intestine plays an important role in immune system. We hypothesized that orally administered HA would be transferred to both blood and lymph. In this study, we investigated how orally administered HA was absorbed from the gastrointestinal tract and how much HA was incorporated. Four HA formulations, HA-2,000, 8,000, 50,000 and 300,000, were administered to rats, and concentrations of HA in blood and lymph were determined. In the HA-2,000 group, the HA plasma concentration increased after oral administration. The highest lymph concentration of HA was also obtained by administration of HA-2,000. The plasma and lymph concentrations slightly increased after oral administration in the HA-8,000 group. On the other hand, little absorption was found in the HA-50,000 and 300,000 groups. It is speculated that smaller molecules of HA are more easily absorbed. HA-2,000 was absorbed mainly through the portal vein and through the lymph in gastrointestinal absorption. This is the first report showing that HAs, large molecular weight and water-soluble molecules, after oral administration are transferred not only into blood but also into lymph.

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Poly(vinyl chloride) is a common plastic that is widely used in many industrial applications. Poly(vinyl chloride) is mixed with additives to improve its mechanical and physical properties and to enable its use in harsh environments. Herein, to protect poly(vinyl chloride) films against photoirradiation with ultraviolet light, a number of tin complexes containing valsartan were synthesized and their chemical structures were established. Fourier-transform infrared spectroscopy, weight loss, and molecular weight determination showed that the non-desirable changes were lower in the films containing the tin complexes than for the blank polymeric films. Analysis of the surface morphology of the irradiated polymeric materials showed that the films containing additives were less rough than the irradiated blank film. The tin complexes protected the poly(vinyl chloride) films against irradiation, where the complexes with high aromaticity were particularly effective. The additives act as primary and secondary stabilizers that absorb the incident radiation and slowly remit it to the polymeric chain as heat energy over time at a harmless level.

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Alginates are polysaccharides that are of interest in various industrial applications. This is due to the viscosifying properties of alginates, which depends on the weight-average molecular weight. The aim of the present study was to evaluate the changes in alginate quality, in terms of the viscosifying power and weight-average molecular weight of the polymer produced by Azotobacter vinelandii mutant strains in shake flasks under microaerophilic conditions. In cultures developed at oxygen transfer rate (OTR) values close to 5 mmol L-1 h-1, the highest viscosifying power (1.75 L g-1) and weight-average molecular weight (3112 ±â€¯150 kDa) were achieved in cultures performed with the AT9 strain. These values were higher than those obtained for the alginates produced by the parental strain ATCC 9046 grown under similar OTR conditions. In contrast, the alginate produced by the GG9 and OPAlgU + exhibited a very low weight-average molecular weight and therefore a poor viscosifying power. Our results have shown that by the cultivation of AT9 strain under microaerophilic conditions it is possible to obtain a polymer having a high weight-average molecular weight and excellent viscosifying capacity. Therefore, it could be a viable strategy for producing alginates for industrial applications.

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Three new polyphosphates were synthesized in good yields by reacting diethylenetriamine with the appropriate phosphate ester in ethanol under acidic conditions. The polyphosphate structures were determined using FT-IR and 1H-NMR spectroscopies, and their elemental compositions were confirmed by EDX spectroscopy. Polyphosphates were added to poly(vinyl chloride) (PVC) at low concentrations to fabricate thin films. The PVC films were irradiated with ultraviolet light for long periods, and the effect of polyphosphates as the photostabilizer was investigated by determining changes in the infrared spectra (intensity of specific functional group peaks), reduction in molecular weight, weight loss, and surface morphology. Minimal changes were seen for PVC films containing polyphosphate compared to that for the blank film. In addition, optical, scanning electron, and atomic force microscopies were used to inspect the surface morphology of films. Undesirable changes due to photodegradation were negligible in PVC films containing additives compared to films containing no additives. In addition, the surfaces were smoother and more homogeneous. Polyphosphates, and in particular ones that contain an ortho-geometry, act as efficient photostabilizers to reduce the rate of photodegradation. Polyphosphates absorb ultraviolet light, chelate with polymeric chains, scavenge radical moieties, and decompose peroxide residues.

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Fourier-transform infrared (FTIR) spectroscopy was applied to predict the degree of hydrolysis (DH%) and weight-average molecular weight (Mw) in milk protein hydrolysates. Both DH% and Mw are important quality parameters of protein hydrolysates. Measuring these parameters and following their development during proteolytic reactions is therefore essential for process control and optimization in industry. In the present study the intercorrelation and the complimentary nature of these parameters were investigated and a partial least squares regression (PLSR) model was developed for the prediction of DH% from molecular weight distributions. Finally, we developed PLSR models based on dry-film FTIR spectroscopy for the prediction of both DH% and Mw. Here spectral changes in the amide region were found to be important for the two calibration models, underlining the advantage of dry-film FTIR measurement. This shows that dry-film infrared spectroscopy is a promising tool for dual prediction of DH% and Mw.

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