Rehydration Process Research Articles

Polysaccharide impregnation: a pretreatment method for improving scallop quality and flavor

The quality and flavor of scallops changes during the fresh dry rehydration process. In order to control the changes after rehydration, a scallop pretreatment method was adopted. The pretreatment method involved impregnating fresh scallops with 0.2 g/100 mL konjac glucomannan (KGM), carrageenan (CA), and sodium alginate (SA) before the drying and rehydration process. After rehydration, the KGM treated samples had better water retention and the highest betaine content. The CA treated samples had a deepened yellow color and the highest content of flavoring amino acids (FAA) and inosine monophosphate (IMP). What’s more, a total of 77 volatile compounds were detected, with a maximum of 15 esters. The highest proportion in the four groups was eugenol, followed by n-hexadecanoic acid, methyl hexadecanoate etc. The SA group had no significant contribution in terms of quality and taste. The samples pretreated with KGM had the best quality, and those pretreated by CA had the best flavor.

Dehydration and Rehydration Kinetics Modeling in the Phytochemical, Aroma, and Antioxidant Capacity of Tree Tomato Fruit Dried with Microwaves and Freeze Driers: A Comparative Study

In the present study, we investigated and compared the effect of microwaves and freeze-drying methods on the dehydration and rehydration kinetics in the phenolic, anthocyanin, aroma profiles, and antioxidant properties of tree tomato fruit (Solanum betaceum). The tree tomatoes were dried using microwaves at 350 W, 500 W, and 650 W, and then freeze-dried. The obtained drying curves were processed to find the most suitable mathematical modeling among the different moisture ratio expressions. Total phenolics, total anthocyanins, total flavonoids total carotenoids, vitamin C, Ferric Reducing Antioxidant Power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were tested. Using High performance Liquid Chromatography (HPLC), phenolic and anthocyanin compound profiles were identified. The aroma profile was analyzed using gas chromatography-MS. The Midilli model, among others, precisely describes the dehydration methodology of all used drying methods with the coefficient of determination R2 = 0.99. On the other hand, the Weibull model precisely describes the rehydration process of the used drying methods (R2 = 0.99). Physical changes (color, shrinkage) were also studied. The freeze-dried tree tomatoes had a high number of phenolic compounds with 3.94 ± 0.26 mg GAE/g and total carotenoid compounds with 0.48 ± 0.04 µg/g. Epicathechin was the most abundant compound among the tested phenolics, followed by Cathechin. The Pelargonidin-3-glucoside was the most abundant anthocyanin whereas in freeze-dried tree tomatoes, 1.22 ± 0.01 mg/g. Fifty-four aroma compounds were detected and quantified. Among others, Eucalyptol was one of the most abundant aroma compounds analyzed in dried tree tomato fruit. Freeze-dried tree tomatoes retained most of the antioxidant and flavor compounds analyzed.

Mechanical compressive behavior of pomelo peel and multilayer polymeric film/foam systems

The study of natural cellular materials offers valuable insights into the superior properties and functions underlying their unique structure and benefits the design and fabrication of advanced biomimetic materials. In this study, we present a systematic investigation of the mechanical behavior of fresh and oven-dried pomelo peels. Density measurements revealed the gradient structure of the pomelo peel, which contributed to its mechanical properties. Step-by-step drying revealed two types of water in the peel. Both uniaxial compression and low-strain hysteresis tests were conducted, and the results showed that fresh pomelo peel exhibits soft elastomer-like behavior, while dried pomelo peel behaves more like conventional synthetic polymer foam. Compared to fresh pomelo peel, dried peel samples showed higher compressive modulus and energy loss in 6, 8 and 10% strain hysteresis tests. The rehydration process was studied using hysteresis tests at three different strains. In addition, multilayer gradient EO/EO and LDPE/LDPE film/foams with 16 alternating layers were produced using the microlayer coextrusion technique. The morphology and mechanical properties were examined and indicated great potential for biomimicking the structure and properties of pomelo peel.

Raman spectroscopy of anhydrous and hydrated aluminum sulfates: Experience from burning coal heaps

AbstractHydrated aluminum‐rich sulfates belong to less widespread secondary minerals on Mars, which are probably connected with hydrothermal alterations. On Earth, such sulfates result from acidic weathering of aluminosilicates, and their formation is controlled by factors such as pH, temperature, or water activity. Physical–chemical conditions can be reconstructed if specific sulfate phases are detected, and therefore, the investigation of sulfate assemblages in high‐temperature settings is important for planetology and exobiology research. Raman spectroscopy is a powerful analytical tool for the discrimination of sulfates, and the degree of hydration, which is a sensitive marker of temperature conditions, can be tracked using this method. However, spectral similarities of sulfates and metastability and rapid transformations may hinder their correct identification. We take advantage of in situ and laboratory Raman spectroscopy to characterize uncommon anhydrous and hydrated Al‐NH4 sulfate mineralogy which forms under elevated temperature at the Anna burning coal waste dump, Alsdorf, Germany, and can be considered as analogous to fumarolic environments. We detected a suite of hydrated Al sulfates (e.g. alunogen, khademite, and tschermigite) in the medium‐temperature zones (~50°C). To minimize possible rehydration processes, we deployed two miniaturized Raman spectrometers (532 and 1064 nm) for field investigations in the high‐temperature zone (~130°C to 150°C). Mixtures of anhydrous (godovikovite and millosevichite) and hydrated phases along with intermediate phases were detected in the field as well as in the laboratory. Such observations are consistent with the premise that the degree hydration of sulfates increase with decreasing temperature. These results confirm that Raman spectroscopy is, despite several analytical challenges, capable of distinguishing Al sulfates, and their hydration states, within complex aggregates and crusts, and future applications in planetary research are promising.

Autonomous Chemistry Enabling Environment-Adaptive Electrochemical Energy Storage Devices

Autonomous Chemistry Enabling Environment-Adaptive Electrochemical Energy Storage Devices

Manipulation of the cyanido-bridged Fe2W2 rhombus in the crystalline state: Co-crystallization, desolvation and thermal treatment

We present the new cyanido-bridged rhombus {[FeII(TPMA)]2[WV(CN)8]2}2– (Fe2W2) (TPMA = tris(2-pyridylmethyl)amine) cluster as a potential Secondary Building Block (SBB) for construction of polynuclear molecular materials. Fe2W2 is formed easily in self-assembly process between [FeII(TPMA)]Cl2 and TBA3[W(CN)8] in H2O/MeOH media, and was co-crystallized in (TBA)2{Fe2W2}⋅2H2O (1), and (TBA)2{Fe2W2}⋅mMeOH⋅nH2O (2) solvated salts, and in (TBA)2{Fe2W2}⋅H3PG⋅mMeOH⋅nH2O (3) (H3PG = phloroglucinol, 1,3,5-trihydroxybenzene; co-former) solvated co-crystal salt. Crystals of 1 undergo reversible SCSC transformation 1 ⇄ 1deh upon controlled dehydration and rehydration processes, whereas crystals of 2 reveal anisotropic thermal expansion during heating from 100 K to room temperature. Both processes involve changes of the selected intermolecular distances or local molecular reorientation involving intermolecular cation–anion and anion-anion contacts. [FeII(TPMA)(µ-NC)2] moieties reveal low-spin (LS) state in each case, however, conformation of the Fe2W2 rings varies from the “staggered” in 1, nearly “eclipsed” in 2 to fully “eclipsed” in 3, which is attributed to various hydrogen bond CNN⋅⋅⋅HO schemes involving the terminal cyanido ligands in [W(CN)8]3– and co-crystallizing molecules. In particular, the conformation of Fe2W2 in 3 is fully controlled by an unprecedented cyclic double hydrogen bond {Fe2W2}⋅⋅⋅H3PG synthon, H3PG forming a bridge over the Fe2W2 rhombus plane through binding the opposite [W(CN)8] corners. This arrangement is co-stabilized by close-to-parallel contacts of H3PG with TPMA walls protruding out of the rhombus plane. The Fe2W2 rhombus is stable in MeOH solution and shows notable affinity to H3PG in the gas phase, which was confirmed by ESI-MS data. UV–Vis-NIR spectroscopy discloses an optical FeII → WV MMCT transition and mixed-valence FeII//III-WV/IV electronic ground state.

Rehydration Characteristics of Beetroot, Sweet Potato and Yam Slices Dried using the Refractance WindowTM Method

This study presents four models' suitability for the rehydration ratio and moisture content history data during the hydration process of beetroot, sweet potato, and yam. The models are the Akinola et al., the Exponential, the Peleg, and the Weibull models. Rehydration occurred at 27◦C for the dehydrated sample slices, which had original dimensions of 25 mm × 25 mm × 3.0 mm. During rehydration, the mass/moisture content history data was recorded for the samples. Regression analysis established that the Akinola et al. Model best fit the rehydration ratio/ mixture content changes vs time history data. The study results show a rapid increase in rehydration in the initial hour of the rehydration process. This increase gradually decreases to a contact equilibrium value. For the yam, sweet potato, and beetroot slices, the rehydration ratio values approached 2.1, 2.1 and 6.5, respectively. This study provides a better understanding of the beetroot, sweet potato, and yam slices' rehydration process. Also, knowledge of the rehydration characteristics of the agro-products will be valuable in the design, operation and optimisation of processing equipment and prediction of water absorption with time.

Effect of Thermal Stimulus on Kinetic Rehydration of Thermoresponsive Poly(diethylene glycol monomethyl ether methacrylate)-block-poly(poly(ethylene glycol) methyl ether methacrylate) Thin Films Probed by In Situ Neutron Reflectivity.

The kinetic rehydration of thin di-block copolymer poly(diethylene glycol monomethyl ether methacrylate)-block-poly(poly(ethylene glycol) methyl ether methacrylate) (PO2-b-PO300) films containing two thermoresponsive components is probed by in situ neutron reflectivity (NR) with different thermal stimuli in the D2O vapor atmosphere. The transition temperatures (TTs) of PO2 and PO300 blocks are 25 and 60 °C, respectively. After the one-step stimulus (rapid decrease in temperature from 60 to 20 °C), the film directly switches from a collapsed to a fully swollen state. The rehydration process is divided into four steps: (a) D2O condensation, (b) D2O absorption, (c) D2O evaporation, and (d) film reswelling. However, the film presents a different rehydration behavior when the thermal stimulus is separated into two smaller steps (first decrease from 60 to 40 °C and then to 20 °C). The film first switches from a collapsed to a semiswollen state caused by the rehydrated PO300 blocks after the first step of thermal stimulus (60 to 40 °C) and then to a swollen state induced by the rehydrated PO2 blocks after the second step (40 to 20 °C). Thus, the kinetic responses are distinct from that after the one-step thermal stimulus. Both the time and extent of condensation as well as evaporation processes are significantly reduced in these two smaller steps. However, the final states of the rehydrated PO2-b-PO300 films are basically identical irrespective of the applied thermal stimulus. Thus, the final state of thermoresponsive di-block copolymer films is not affected by the external thermal stimuli, which is beneficial for the design and preparation of sensors or switches based on thermoresponsive polymer films.

Preparation of hollow nanosphere of 5-fluorouracil/layered double hydroxide and its cellular cytotoxicity

We have first prepared the layered double hydroxide (LDH)/carbon nanosphere (CNS) composite by mixing the LDH gel containing methoxide interlayer anion with the CNS template (particle size of 300–700 nm) suspension in methanol at room temperature under ultrasonication. The SEM observation indicates that the CNS core was uniformly covered with the LDH thin film made up by fine plate-like particles to form the composite. Then, the intercalation of anticancer drug, 5-fluorouracil (5-FU), into the LDH interlayer was carried out by the calcination-rehydration reaction and the solid products were analyzed using XRD, FT-IR, SEM, TEM etc. During the calcination process at 500 °C for 3 h, the CNS core was removed by combustion and the LDH shell became the hollow LDH oxide nanosphere. In the following rehydration process at 60 °C for 24 h, this oxide precursor was reconstructed the hollow LDH nanosphere having the surface of coral-like structure (spontaneously formed LDH particles) incorporating 5-FU anion in the interlayer. Finally, the anticancer drug efficacy in vitro of the products was estimated by using the WST-8 assays in HeLa cell lines. As the result, the hollow nanosphere of the 5-FU/LDH performed an improvement of drug efficacy compared to the conventional plate-like particle of the 5-FU/LDH as the reference and the naked 5-FU itself at the same 5-FU concentration.

Mathematical Description of Changes of Dried Apple Characteristics during Their Rehydration

The mathematical description of changes of dried apples characteristics (mass gain, volume increase, dry matter loss, rehydration indices, and colour) during their rehydration was performed. The effect of conditions of both processes on model parameters were also considered. Apple slices (3 and 10 mm) and cubes (10 mm) were dried in natural convection (drying air velocity 0.01 m/s), forced convection (0.5 and 2 m/s), and fluidisation (6 m/s). Drying air temperatures (Td) were equal to 50, 60, and 70 °C. The rehydration process was carried out in distilled water at the temperatures (Tr) of 20, 45, 70, and 95 °C. Mass gain, volume increase, and dry matter loss were modelled using the following empirical models: Peleg, Pilosof–Boquet–Batholomai, Singh and Kulshrestha, Lewis (Newton), Henderson–Pabis, Page, and modified Page. Colour changes were described through applying the first-order model. Artificial neural networks (feedforward multilayer perceptron) were applied to make the rehydration indices and colour variations (ΔE) dependent on characteristic dimension, Td, drying air velocity, and Tr. The Page and the modified Page models can be considered to be the most appropriate in order to characterise the mass gain (RMSE = 0.0143–0.0619) and the volume increase (RMSE = 0.0142–0.1130), whereas the Peleg, Pilosof–Bouquet–Batholomai, and Singh and Kulshrestha models were found to be the most appropriate to characterise dry matter loss (RMSE = 0.0116–0.0454). The ANNs described rehydration indices and ΔE satisfactorily (RMSE = 0.0567–0.0802). Both considered process conditions influenced (although in different degree) the changes of the considered dried apple characteristics during their rehydration.

Sulfonated-silica/carbon composites from rice husk as heterogeneous catalysts in fructose conversion: The effect of controlling carbonization temperature of rice husk on its physicochemical properties and catalytic activities

A simple preparation of sulfonated-silica/carbon (SiO2/C–SO3H) composites from rice husk at different carbonization temperatures have been demonstrated. These composites have been employed as heterogeneous Brønsted acid catalysts in converting fructose into methyl levulinate (ML) in a one-pot reaction that involves dehydration, etherification, and rehydration processes. As the carbonization temperature increased, the results from N2 adsorption-desorption isotherm showed porosity and the surface area of the composites were increased. The acid strength was also increased, as confirmed by the Temperature-Programmed Desorption of Ammonia (NH3-TPD) profile. Energy-Dispersive X-ray (EDX) analysis revealed the SiO2/C weight ratios of the composite were increased, but S/C weight ratios were decreased. 90% yield of ML was synthesized at 165 °C for 7 h in methanol solvent. Pearson's correlation test showed that hydrophilicity is the main factor in obtaining high turnover number (TON). The yield was dropped in recycling experiments due to carbonaceous deposition, which caused deactivation, as corroborated by the Thermogravimetric Analysis (TGA) and N2 sorption analysis. These composites were also able to convert fructose into 56–74% yield of 5-hydroxymethylfurfural (HMF) in dimethylsulfoxide (DMSO) solvent at 130 °C for 5 h.

Investigating shrinkage corrected drying characteristics, rehydration, color profile and microstructural evolution during solar drying of pineapple slices

AbstractThe study describes the solar drying characteristics of pineapple slices with incorporation of shrinkage and influence of drying and rehydration on structural alterations, color profile and microstructure. Samples were dried in mixed mode solar dryer at an air velocity of 0.5 m/s, with recorded average solar radiation, ambient and drying chamber temperature of 665 W/m2, 33°C and 65°C, respectively, from initial moisture content of 89.9% to a final moisture content of 23% in 6.5 h. Samples showed 43.7% higher drying rate and 82.25% lesser moisture diffusivity on consideration of shrinkage. Moisture diffusivity was increased with a reduction in moisture content during drying on ignoring the shrinkage, while it was initially increased and then gradually reduced at later hours when shrinkage effect was considered. The slices showed overall shrinkage of 86.95% during drying but could recover only 35–45.57% of its volume during rehydration. The water absorption and volume recovery were consistently higher at rehydration temperature of 60°C followed by 45°C and 30°C. Solar dried and rehydrated samples demonstrated overall color change of 16.80 ± 1.15 and 5.87 ± 2.5–7.56 ± 1.43, respectively. Scanning electron micrographs of solar dried samples presented collapsed cellular matrix but rehydrated samples showed porous microstructure indicating regaining of honeycomb network.Practical ApplicationsSolar drying is an essential sustainable approach to reduce the tremendous post‐harvest losses of fruits and it also offers the advantages of energy cost saving, higher affordability level and greater payback power to farmers. Present study explored the drying characteristics, followed by rehydration characteristics and effect of drying and rehydration on quality attributes of pineapple slices. Therefore, results are helpful for food processors and engineers in optimization of drying and rehydration processes to obtain best quality products, shelf‐life extension of perishable fruits. Solar dried pineapple slices will give better returns to farmers. Moreover, dried pineapple can be utilized as dried chips/snacks, powder, etc. and also can be further rehydrated to reconstitute for utilization in different value added food products like ice‐cream, cakes, flakes, granules etc.

Biofunctionalization of Xenogeneic Collagen Membranes with Autologous Platelet Concentrate-Influence on Rehydration Protocol and Angiogenesis.

Background: The aim of this study was to analyze possible interactions of different xenogeneic collagen membranes (CM) and platelet-rich fibrin (PRF). PH values were evaluated in the CM rehydration process with PRF, and their influence on angiogenesis was analyzed in vivo. Materials and Methods: Porcine (Bio-Gide®, Geistlich)- and bovine-derived collagen membranes (Symbios®, Dentsply Sirona) were biofunctionalized with PRF by plotting process. PRF in comparison to blood, saline and a puffer pH7 solution was analysed for pH-value changes in CM rehydration process in vitro. The yolk sac membrane (YSM) model was used to investigate pro-angiogenic effects of the combination of PRF and the respective CM in comparison to native pendant by vessel in-growth and branching points after 24, 48 and 72 h evaluated light-microscopically and by immunohistochemical staining (CD105, αSMA) in vivo. Results: Significantly higher pH values were found at all points in time in PRF alone and its combined variants with Bio-Gide® and Symbios® compared with pure native saline solution and pH 7 solution, as well as saline with Symbios® and Bio-Gide® (each p < 0.01). In the YSM, vessel number and branching points showed no significant differences at 24 and 48 h between all groups (each p > 0.05). For PRF alone, a significantly increased vessel number and branching points between 24 and 48 h (each p < 0.05) and between 24 and 72 h (each p < 0.05) was shown. After 72 h, CM in combination with PRF induced a statistically significant addition to vessels and branching points in comparison with native YSM (p < 0.01) but not vs. its native pendants (p > 0.05). Summary: PRF represents a promising alternative for CM rehydration to enhance CM vascularization.

Cut orientation effect on mass transfer: Drying and rehydration of yellow sweet potato cylinders

This work aimed to evaluate how cut orientation affects mass transfer during the drying and rehydration process. Sweet potato cylinders of 1.90 cm of diameter and 0.50 cm of height were prepared. Three cut orientations were carried out regarding the vascular tissue orientation, preparing longitudinal, transverse and oblique (45°) cuts. In addition, osmotic pretreatment (50°Brix sucrose solution) was also evaluated. Convective drying and rehydration kinetics were evaluated at a constant temperature. As results, cut orientation and osmotic pretreatment did not affect the drying kinetics. However, transverse cut without osmotic pretreatment presented less shrinkage than the other cut orientations. On the other hand, rehydration process was affected by cut orientation, being longitudinal cut the slowest sample absorbing water. In conclusion, both the cut orientation and osmotic dehydration did not show important effects on convective drying. Despite that, cut orientation affected shrinkage and rehydration kinetics of sweet potato cylinders.

Dry‐salted cod (Gadus morhua) rehydration assisted by pulsed electric fields: modelling of mass transfer kinetics

BACKGROUNDDry‐salted cod (Gadus morhua) must be rehydrated before consumption and this step can take up to 5 days. Desalting of cod on an industrial scale poses many problems, mainly related to the long processing times and the quality of the final product. For this reason, many researchers have focused on finding new desalting methods to improve mass transfer. The application of pulsed electric fields (PEF) has been proposed as an alternative method for improving mass transfer in many food processes. However, there is no previous literature on the use of PEF to improve animal tissue rehydration. Therefore, the present study aimed to investigate the influence of two PEF pre‐treatments [PEF (1) 500 V cm−1 and PEF (2) 1000 V cm−1] on mass transport kinetics during the rehydration process of salted cod. The rehydration process was carried out under static conditions for 6 days, immersing dry‐salted cod samples in tap water (5 ± 0.5 °C).RESULTSThe results show that the use of PEF technology increases the rate of the rehydration process of dry‐salted cod and influences the redistribution of salt. In general, the samples pre‐treated with PEF showed higher weight gain and lower salt loss than the control samples during the rehydration process.CONCLUSIONThe application of PEF prior to rehydration of salted cod samples could be of interest to the food industry as a result of a higher process yield (higher weight gain) and the possibility to reduce the water renewal because less NaCl is lost in the wastewater. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The Improvement of Reserve Polysaccharide Glycogen Level and Other Quality Parameters of S. cerevisiae Brewing Dry Yeasts by Their Rehydration in Water, Treated with Low-Temperature, Low-Pressure Glow Plasma (LPGP)

The increasing popularity of active dry yeast arises from its properties, such as ease of storage, and simplicity of preparation and dosing. Herein, we elaborate on the effect of plasma-treated water (PTW) under air atmosphere (PTWAir) and nitrogen (PTWN) on the improvement of the reserve polysaccharide glycogen level and other quality parameters of S. cerevisiae brewing dry yeast in comparison with the non plasma-treated water (CW). For this purpose, strains of top-fermenting (S. cerevisiae T58 (poor quality), S33 (poor quality)) and bottom-fermenting (S. pastorianus W30/70 (poor quality)) yeast stored one year after opening and S. cerevisiae US-05 (fresh strain) were selected to examine the influence of PTWs toward the quality parameters of yeast biomass after the rehydration and fermentation process. The obtained results showed that in the case of poor quality yeast strains, PTWAir increased glycogen content after the rehydration and fermentation process, which was a favorable trend. A similar increase was observed for the trehalose content. Results showed that PTWN significantly reduced the number of yeast cells in ale strains and the viability of all analyzed samples. The lowest viability was observed in Sc S33 strain for PTWAir (41.99%), PTWN (18.6%) and CW (22.86%). PTWAir did not contribute to reducing the analyzed parameter; in particular, the results of Sc T58 yeast strain’s viability are shown: PTWAir (58.83%), PTWN (32.28%) and CW (43.56%). The obtained results suggest that rehydration by PTWN of dry yeast with a weakened condition is not recommended for both qualitative and cost-related reasons, while PTWAir significantly contributed to the improvement of some yeast parameters after rehydration and fermentation (higher glycogen and trehalose content).

Rehydration Compensation of Winter Wheat Is Mediated by Hormone Metabolism and De-Peroxidative Activities Under Field Conditions.

Water deficit and rehydration frequently occur during wheat cultivation. Previous investigations focused on the water deficit and many drought-responsive genes have been identified in winter wheat. However, the hormone-related metabolic responses and de-peroxidative activities associated with rehydration are largely unknown. In this study, leaves of two winter wheat cultivars, “Hengguan35” (HG, drought-tolerant cultivar) and “Shinong086” (SN, drought-sensitive cultivar), were used to investigate water deficit and the post-rehydration process. Rehydration significantly promoted wheat growth and postponed spike development. Quantifications of antioxidant enzymes, osmotic stress-related substances, and phytohormones revealed that rehydration alleviated the peroxidation and osmotic stress caused by water deficit in both cultivars. The wheat cultivar HG showed a better rehydration-compensation phenotype than SN. Phytohormones, including abscisic acid, gibberellin (GA), jasmonic acid (JA), and salicylic acid (SA), were detected using high-performance liquid chromatography and shown to be responsible for the rehydration process. A transcriptome analysis showed that differentially expressed genes related to rehydration were enriched in hormone metabolism- and de-peroxidative stress-related pathways. Suppression of genes associated with abscisic acid signaling transduction were much stronger in HG than in SN upon rehydration treatment. HG also kept a more balanced expression of genes involved in reactive oxygen species pathway than SN. In conclusion, we clarified the hormonal changes and transcriptional profiles of drought-resistant and -sensitive winter wheat cultivars in response to drought and rehydration, and we provided insights into the molecular processes involved in rehydration compensation.

Dehydration of glucose over sulfate impregnated ZnO (hexagonal-monoclinic) catalyst in dimethyl sulfoxide (DMSO) medium: Production, separation, and purification of 5-hydroxymethylfurfural (5-HMF) with high purity

Dehydration of glucose for the production and separation of 5-hydroxymethylfurfural (5-HMF) with high purity has been performed. For selective production of 5-HMF from glucose, a new sulfated-ZnO catalyst with a combined hexagonal-monoclinic phase was developed and characterized by several techniques. The catalyst characterization results demonstrated a significant variation of physicochemical properties of hexagonal ZnO after sulfate impregnation. The glucose dehydration was performed in a glass reactor in a dimethyl sulfoxide (DMSO) medium. The effect of several important reaction parameters including temperature (120–160 °C), time (1–8 h), catalyst loading (25–100 wt%), and sulfate loading on ZnO with respect to glucose (1.5–4.5M) was evaluated. Results demonstrated that the sulfated-ZnO catalyst containing both the Brønsted (B) and Lewis (L) acid sites was very active and selective to 5-HMF compared to pure hexagonal ZnO containing only Lewis acidic sites (LAS). It was also observed that the higher (B + L) acidity of catalysts propagated the rehydration process, which led to the formation of various unwanted side products. The maximum glucose conversion of 96.2% with ~35% yield of 5-HMF was obtained at 160 °C after 6 h of reaction, with 2.5M-SO42−/ZnO catalyst. Among all others, the 2.5M-SO42−/ZnO catalyst was the best due to the presence of an optimum acidity with an appropriate B/L ratio. Further, the catalyst separation and recycling studies were performed. The results revealed that the 2.5M-SO42−/ZnO catalyst could be recycled multiple times without substantial loss of catalytic activity and 5-HMF yield. Furthermore, a liquid-liquid extraction process was developed, demonstrating that almost 100% of 5-HMF could be extracted from the product solution with ~97% purity.

Effectiveness of Isotonic Beverages and Mineral Water Beverages to Recovery Time after Cooper Test

Exercise is one way that can be done towards a healthy life. When exercising the body will lose a lot of fluid in the form of electrolytes through sweat. Most people after exercise will consume mineral water which causes a decrease in the concentration of sodium in the blood plasma thus reducing thirst further delaying the rehydration process. Currently popular with isotonic beverages that have a similar osmolarity value of body fluids, and have the benefit of restoring lost body fluids so that the body avoids dehydration. This study aims to determine the effectiveness of isotonic drinks and mineral water to the recovery of physical exercise after conducting a Cooper Test. The method used is experimental research Pretest - posttest Control Group Design.

Transcriptome analysis of Auricularia fibrillifera fruit-body responses to drought stress and rehydration

BackgroundDrought stress severely restricts edible fungus production. The genus Auricularia has a rare drought tolerance, a rehydration capability, and is nutrient rich.ResultsThe key genes and metabolic pathways involved in drought-stress and rehydration were investigated using a transcriptome analysis to clarify the relevant molecular mechanisms. In total, 173.93 Mb clean reads, 26.09 Gb of data bulk, and 52,954 unigenes were obtained. Under drought-stress and rehydration conditions, 14,235 and 8539 differentially expressed genes, respectively, were detected. ‘Tyrosine metabolic’, ‘caffeine metabolism’, ‘ribosome’, ‘phagosome’, and ‘proline and arginine metabolism’, as well as ‘peroxisome’ and ‘mitogen-activated protein kinase signaling’ pathways, had major roles in A. fibrillifera responses to drought stress. ‘Tyrosine’ and ‘caffeine metabolism’ might reveal unknown mechanisms for the antioxidation of A. fibrillifera under drought-stress conditions. During the rehydration process, ‘diterpenoid biosynthesis’, ‘butanoate metabolism’, ‘C5-branched dibasic acid’, and ‘aflatoxin biosynthesis’ pathways were significantly enriched. Gibberellins and γ-aminobutyric acid were important in the recovery of A. fibrillifera growth after rehydration. Many genes related to antibiotics, vitamins, and other health-related ingredients were found in A. fibrillifera.ConclusionThese findings suggested that the candidate genes and metabolites involved in crucial biological pathways might regulate the drought tolerance or rehydration of Auricularia, shedding light on the corresponding mechanisms and providing new potential targets for the breeding and cultivation of drought-tolerant fungi.