Pretreated Samples Research Articles

Microwaves as sustainable approach for artificial ripening of date fruit cv. Khupra to reduce fruit waste

Date fruit ripening depends upon various factors, including climate, environment, soil type, air and humidity. Due to these factors, some cultivars of date fruit are unable to ripen on the trees and deteriorates. Thus a significant quantity of date fruit is wasted every year, which impose significant concerns on food security. Therefore, this study investigated the effect of microwave pre-treatment for ripening of dates. For this purpose, date fruits cv. Khupra at the Khalal stage were pretreated at different microwave power level (30, 50 and 80 W) and time (30, 40 and 50 s) combinations for the improved microstructural and compositional characteristics. Afterwards, the treated samples were stored at relative humidity (50 %) and temperature (50 °C). The data indicated that microwave pretreated dates retained better quality in comparison to sun dried samples. The microwave treated fruits exhibited TSS contents up to 60.3 ± 0.09 °Brix, a whiteness index of up to 15.4, and an antioxidant capacity of up to 78 ± 0.04 %. Texture profile analysis also revealed that the sundried fruits have more hardness of 724 ± 0.01 (g-force) compared to microwave pretreated samples which was supported by the Scanning electron microscopy analysis. Moreover, FTIR spectra readings indicated the presence of various dietary fiber components such as cellulose, lignin, hemicellulose, fructose, glucose, arabinose, glactomannans, pectins, and organic acids retained in microwave pretreated dates. In short, Microwave pretreatment can potentially replace the conventional sun drying method for production of superior quality ripened dates.

Effect of Preliminary Treatment by Pulsed Electric Fields and Blanching on the Quality of Fried Sweet Potato Chips.

The effects of pulsed electric fields (PEF) and blanching pretreatments on frying kinetics, oil content, color, texture, acrylamide (AA) content, and microstructure have been investigated in this paper. The total PEF pretreatment duration was tPEF = 0.2 s with an intensity of E = 1 kV/cm; blanching was studied at 85 °C for 5 min. The results demonstrated that pretreatment significantly reduced the moisture ratio and oil content by 25% and 40.33%, respectively. The total color change ΔE value of the pretreated samples was lower than that of the untreated samples. In addition, pretreatment increased the hardness of the sample after frying, and the AA content in the fried samples pretreated with PEF + blanching was reduced by approximately 46.10% (638 μg/kg). Finally, fried sweet potato chips obtained by the combined pretreatment exhibited a smoother and flatter cross-sectional microstructure.

Application of Central Composite Design and Superimposition Approach for Optimization of Drying Parameters of Pretreated Cassava Flour.

The primary goals of this study were to identify the influence of temperature and drying time on pretreated cassava flour, as well as the optimal settings for the factors and to analyze the microstructure of cassava flour. The experiment was designed using the response surface methodology with central composite design and the superimposition approach in order to assess the effect of drying temperature (45.85-74.14 °C) and drying time (3.96-11.03 h) and the optimal drying conditions of the cassava flour investigated. Soaking and blanching were applied as pretreatments to freshly sliced cassava tubers. The value moisture content of cassava flour was between 6.22% and 11.07%, whereas the observed whiteness index in cassava flour ranged from 72.62 to 92.67 in all pretreated cassava flour samples. Through analysis of variance, each drying factor, their interaction, and all squared terms had a substantial impact on moisture content and whiteness index. The optimized values for drying temperature and drying time for each pretreated cassava flour were 70 °C and 10 h, respectively. The microstructure showed a non-gelatinized, relatively homogeneous in size and shape sample with pretreatment soaked in distilled water at room temperature. These study results are relevant to the development of more sustainable cassava flour production.

Recovering biogas and nutrients via novel anaerobic co-digestion of pre-treated water hyacinth for the enhanced biogas production

The present investigation explores the feasibility of generating biogas from water hyacinth (WH) through a pretreatment process. The WH samples were subjected to a high concentration of H2SO4 pretreatment to enhance biogas production. The H2SO4 pretreatment aids in breaking down the lignocellulosic materials found in the WH. Additionally, it helps modify the cellulose, hemicellulose, and lignin, which assists in the anaerobic digestion process. The samples underwent pretreatment with 5% v/v H2SO4 for 60 min. Biogas production was conducted for both untreated and pretreated samples. Furthermore, sewage sludge and cow dung were used as inoculants to promote fermentation in the absence of oxygen. The results of this study demonstrate that the pretreatment of water hyacinth with 5% v/v H2SO4 for 60 min considerably enhances biogas production through the anaerobic co-digestion process. The maximum biogas production was recorded by T. Control-1, with a production rate of 155 mL on the 15th day compared to all other controls. All the pretreated samples showed the highest biogas production on the 15th day, which is comparatively five days earlier than the untreated samples. In terms of CH4 production, the maximum yield was observed between the 25th and 27th days. These findings suggest that water hyacinth is a viable source of biogas production, and the pretreatment method significantly improves biogas yield. This study presents a practical and innovative approach to biogas production from water hyacinth and highlights the potential for further research in this area.

Improving the hot air drying of garlic slices by perforation synergistic alcohol pretreatment

Long processing time represents a serious challenge in hot air drying since it led to high energy consumption and quality deterioration. A synergistic pretreatment of artificial perforation and alcohol maceration (PAT) was proposed in this study to improve hot air drying of garlic. Samples without pretreated, perforated, and subjected to alcohol pretreatments were used as control. The results showed that PAT pretreatment significantly reduced the drying time and energy consumed by 36.67%. Analysis showed that the mechanisms underlying the highest drying rate of PAT pretreated sample included pre-dehydration, capillary flow promotion and cell permeability enhancement. Samples pretreated with PAT exhibited the highest whiteness value, minimum shrinkage, lowest brittleness, and especially the highest content of volatile components, which is essential for its application as a spice. The antioxidant activity, total phenolics and allicin content were low in the PAT samples compared with other samples. This study provides a simple and effective approach to improve the drying of garlic.

Separation and identification of monoglucuronides of vitamin D3 metabolites in urine by derivatization-assisted LC/ESI-MS/MS using a new Cookson-type reagent.

A liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) method was developed using a new Cookson-type reagent, 4-[4-(1-pipelidinyl)phenyl]-1,2,4-triazoline-3,5-dione (PIPTAD), to analyze the monoglucuronides (Gs) of vitamin D3 metabolites in human urine. The G of 23S,25-dihydroxyvitamin D3 [23,25(OH)2D3] was previously found as a major metabolite of vitamin D3 in the urine, but its conjugation position remained undetermined. Determination of the position was an important research issue to clarify the whole picture of the excretion of surplus 25-hydroxyvitamin D3 [25(OH)D3, the circulating form of vitamin D3] in humans. After the pretreated urine sample was derivatized with PIPTAD, the peak corresponding to the G of 23,25(OH)2D3 was satisfactorily separated from the urine-derived interfering substances on reversed-phase LC, which could not be achieved by using the previous analogous reagent, DAPTAD. The PIPTAD-derivatized Gs of the vitamin D3 metabolites provided characteristic product ions useful for identifying the conjugation positions during the MS/MS. Accordingly, we successfully determined the glucuronidated position of 23,25(OH)2D3 to be the C23-hydroxy group. The developed method also enabled the simultaneous detection of Gs of 25(OH)D3 and 24R,25-dihydroxyvitamin D3 as well as 23,25(OH)2D3-23-G without interference from the urine components.

Sorptive removal of per- and polyfluoroalkyl substances (PFAS) in organic-free water, surface water, and landfill leachate and thermal reactivation of spent sorbents

This study evaluated the performance of five commercially available granular activated carbons (GACs) derived from different sources for the removal of short-chain and long-chain per- and polyfluoroalkyl substances (PFAS) from raw and pretreated landfill leachate using ozonation to break down organic substances. The adsorption isotherms of PFAS on GAC in organic-free water and surface water were also established to understand the effect of water chemistry. The results demonstrated that bituminous GACs have the highest adsorption capacity compared to GACs made from coconut shells and lignite coal. The GAC adsorption of PFAS in landfill leachate was two orders of magnitude lower than that in surface water. Pretreatment of leachate by ozonation moderately increased the adsorption of PFAS on GAC. This is the first time that PFAS isotherm data are available for mainstream GACs in raw and pretreated landfill leachate samples. Such data can be used to design a GAC treatment system for removing PFAS from leachate. Furthermore, our results showed that GAC contaminated with PFAS in landfill leachate could be effectively regenerated using conventional muffle and tube furnaces, indicating that the presence of other substances in the leachate has no significant impact on the reactivation of the GAC. Lastly, the results indicate that induction heating is an efficient and rapid method for thermally reactivating GAC contaminated with various PFAS.

Water Quality Assessment Using Activated Carbon from Cocoshells in Lake Mainit, Philippines

Mining activities pose environmental impacts especially when the operation is near bodies of water, thus, affecting water quality. As these environmental impacts are growing, there is a pressing need for increased intervention studies to improve water quality. This study aimed to evaluate the effectiveness of granulated activated carbon made from coconut shells in reducing heavy metal levels and enhancing the water quality of Lake Mainit located at Agusan del Norte and Surigao del Norte, Philippines. Silica sand, pumice stones, and white marble chips were added to a glass tank with the granulated activated carbon made from coconut shells. The water sample underwent various laboratory tests. The atomic absorption spectrometry flame technique was used to analyze the heavy metals lead and cadmium. Gravimetric method was employed in total suspended solids and total dissolved solids, and nephelometric method for turbidity. Pre-treated water sample analysis regarding lead, total dissolved solids, and turbidity are within the permissible limits, however, total suspended solids and cadmium concentration surpassed the allowable limits for Class A waters. Removal efficiency in terms of heavy metal concentration and the significant difference of parameters between the water sample before and after intervention were calculated. Results showed that after the intervention, activated carbon made from coconut shells were able to reduce the cadmium level present in the water sample. It also improved the quality of water within permissible limits. Hence, the activated carbon made from agricultural waste such as coconut shells has considerable potential to provide better water quality.

The volatile profile of pasteurized leek (Allium ampeloprasum var. porrum) and Brussels sprouts (Brassica oleracea var. gemmifera) (products), as a witness to (bio)chemical reactivity, influenced by pretreatment and successive refrigerated storage

Processing can affect (bio)chemical conversions in vegetables and can act on their volatile properties accordingly. In this study, the integrated effect of pretreatment and pasteurization on the volatile profile of leek and Brussels sprouts and the change of this profile upon refrigerated storage were investigated. Pretreatments were specifically selected to steer biochemical reactivities to different extents. Volatile profiles were analyzed by headspace-solid phase microextraction-gas chromatography-mass spectrometry. For both vegetables, it was observed that different pretreatments prior to a pasteurization step led to diverse volatile profiles. The differences in volatile profiles observed in the different samples were presumably attributed to the different degrees of enzymatic conversions, further conversions of enzymatically formed products and thermally induced reactivities. Interestingly, the observed initial relative differences between volatile profiles of differently pretreated pasteurized samples were still observed after a refrigerated storage of 4 weeks at 4 °C. In conclusion, refrigerated storage only limitedly affected the resulting volatile profile.

Investigation of osmosonication pretreated chili (Capsicum frutescensL.) drying in solar‐assisted fluidized bed dryer utilizing dehumidified air

AbstractThe heat and moisture sensitivity of spices and a consistent supply of electrical energy is the challenging factors in developing a relevant drying system for rural applications. A novel solar‐assisted fluidized bed dryer was developed for drying locally harvested unique spices like bird's eye chili (Capsicum frutescens L.). The chili was pretreated by the osmosonication method prior to drying to expedite the elimination of intercellular and intracellular moisture. In order to make the dryer more reliable, the recirculation strategy and dehumidified air supplied by liquid desiccant were acclimatized to constrict the heat loss through outflowing moist drying air. The experiments were conducted up to the permissible water activity (0.4–0.6) under variable drying conditions (50–70°C). By raising the ambient inlet temperature (maximum 25.9°C), the developed solar FBD was able to supply the drying air up to 50°C (in continuous mode) and a maximum of up to 65°C without aiding any heat energy sources except solar. It was found that osmosonication opened up the possibility of reducing the required drying temperature (↓10°C) and energy consumption (up to ↓31.7%). The dried red chili was fortified by pretreatment, as it could retain more capsaicin (>6%) and reddishness (>5%) compared to untreated samples. The Fourier transform infrared (FTIR) analysis showed the structural integrity of pretreated samples. The relative humidity of the drying air could be reduced by as much as 5% using the composite lithium chloride and calcium chloride (35% + 5%) desiccant dehumidifier. Dehumidification of air was found advantageous, with an inclination to shorten the drying duration (about ↓0.5 h) and energy (↓12.43%).Practical ApplicationsThere are various commercially valuable unique agro‐products that are exclusively being produced in rural areas. The inaccessibility of relevant drying technology and inconsistency of grid electricity are the main constraints in the value addition of those products. Open sun drying is most popular in rural areas; however, it is not reliable, and the product quality can't maintain. The developed solar‐assisted fluidized bed dryer utilizing dehumidifying air and integrated with osmosonication pretreatment could be a relevant technology for drying heat and moisture‐sensitive products like spices. Cost‐effective drying using locally accessible solar energy compared to open sun drying and superior dried product quality can be achieved by using the current drying system.

Impacts of Rejuvenator Pretreatment and Marination on Quality Characteristics of Reclaimed Asphalt Pavement

To mitigate the potential cracking performance issues of high reclaimed asphalt pavement (RAP) asphalt mixtures, rejuvenators can be added to restore the rheological and chemical properties of the RAP binder. Traditionally, rejuvenators are pre-blended into the virgin binder before mixing, which may limit the direct interaction between the rejuvenator and RAP. Therefore, alternative methods of adding rejuvenators by pretreating RAP with appropriate marination before mixing with virgin materials should be considered to potentially enhance the rejuvenating effectiveness of these products. In this study, three RAP pretreatment methods (spray-on, emulsified, and foamed rejuvenators) were explored. The effects of each pretreatment method on RAP quality properties were characterized through workability evaluation based on the Dongre Workability Test (DWT), durability assessment based on the Cantabro test, and grayscale image analysis. From these results, the most effective pretreatment method was selected to evaluate the impact of marination on RAP quality via the same characterization techniques. Four marination conditions were evaluated, including 3 and 7 days at 25°C, and 1.5 and 3 h at 135°C. Furthermore, asphalt binders extracted from untreated and pretreated RAP samples at selected marination conditions were tested for rheological and chemical characterization. Test results indicated that RAP quality significantly improved with pretreatment with the rejuvenator, but the degree of improvement varied depending on the rejuvenator dosage and application method, among other factors. Marination also affected the RAP binder properties but did not significantly improve the overall quality characteristics of the RAP in relation to DWT, Cantabro, and grayscale image analysis.

Enhancement in anaerobic biogas conversion by visible light photocatalytic Pre-treatment of rice husk with indium vanadate decorated titanium dioxide nanocomposite

Production of biogas from crop wastes via the biological route is one of the most demanding and promising technologies for energy generation for sustainable development. The incorporation of photocatalytic pretreatment as a robust catalytic technique has been reported to enhance the overall efficiency of the anaerobic process. Rice husk has been pretreated using Indium Vanadate decorated Titania nanocomposite to enhance its biodegradability for biogas production. Scanning electron microscopy confirmed the deformities and crevices that may support the role of the photocatalytic pretreatment in the subsequent anaerobic degradation process. FT-IR spectroscopy investigated the structural characteristics of pretreated and photolyzed rice husk samples. Gas chromatography was used to quantify the CH4 content of biogas yield after different treatments of rice husk. Photocatalytic pretreatment of rice husk showed 2.8 times higher cumulative biogas production than raw or untreated rice husk. Statistical analysis showed a significant difference between natural and pretreated rice husk biogas yield with a p-value of < 0.01. The results suggest that visible light active photocatalysis is an efficient pretreatment method that can facilitate the microbes to degrade the rigid rice husk for enhanced biogas production via the anaerobic digestion process.

Understanding triethylammonium hydrogen sulfate ([TEA][HSO4]) pretreatment induced changes in Pennisetum polystachion cell wall matrix and its implications on biofuel yield

Biofuel potential of a widely grown perennial grass, Pennisetum polystachion, was analyzed using triethylammonium hydrogen sulfate ([TEA][HSO4]) pretreatment. The optimum pretreatment condition was selected based on the delignification efficiency. 80% [TEA][HSO4] at 140 °C for 45 min at 10% sample load, yielding high delignification rate (65.8%) was selected as the optimum pretreatment condition. Recycling of [TEA][HSO4] showed up to 90% IL recovery and significant delignification rates. Glucan yield in the biomass increased to 67.8%, whereas digestibility of biomass enhanced from 16.7% to 84.1%. Extensive deferuloylation (88%) and decoumarylation (86.4%) were observed in the sample following pretreatment. Diferulic acids were not detected in pretreated samples indicating their complete removal. HMF (0.1 mg/mL) and furfural (0.001 mg/mL) produced during pretreatment were very low compared to conventional methods. FTIR and XRD confirmed pronounced delignification and hemicellulose dissolution, and FESEM showed a marked difference in the surface morphology, including defibrillation and enhanced porosity. An ethanol yield of 275 mg/g biomass (84.7% of theoretical maxima) was achieved using Saccharomyces cerevisiae MTCC 36 after 15 h of fermentation. The results obtained from the current study can shed light on utilizing P. polystachion as a potential biofuel feedstock using a low-cost ionic liquid [TEA][HSO4].

Enzymatic hydrolysate of water hyacinth with NaOH pretreatment for biobutanol production via ABE fermentation by Clostridium beijerinckii JCM 8026

Water hyacinth (WH; Eichhornia crassipes) is an invasive and free-floating aquatic plant that is rapidly spreading over the world causing various environmental problems. The utilization of WH as a feedstock for biofuel production is a challenging solution to overcome the environmental problem as well as address the energy shortage. Due to the complex structure of lignocellulosic materials, pretreatment is an inevitable step to maximize the sugar yield before being used as a substrate in fermentation. The aim of this study was to investigate the utilization of WH for biobutanol production via acetone-butanol-ethanol fermentation by Clostridium beijerinckii JCM 8026. The WH was pretreated with sodium hydroxide (NaOH) at various concentrations [0, 2, and 4% (w/v)], reaction times (30, 60, and 90 min), and temperatures (80, 100, and 120 °C). The pretreatment results were optimized using response surface methodology with a Box-Behnken design and Minitab software analysis. The maximum total sugar concentration (21.05 g/L) following cellulose digestion was obtained after a 2% (w/v) NaOH for 90 min at 100 °C. This hydrolysate slurry gave a subsequent butanol concentration, yield, and productivity of 2.09 g/L, 0.15 g/g, and 0.012 g/L/h, respectively, following C. beijerinckii JCM 8026 fermentation. To help understand the effect of the pretreatments, changes in the pretreated samples were observed by surface area analyses, scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis.

Abstract 3281: GEN1042 (DuoBody-CD40x4-1BB)®in combination with PD-1 blockade reverses T-cell exhaustion in vitro

Abstract GEN1042 (DuoBody®-CD40x4-1BB) is an investigational, novel, agonistic, bispecific antibody that combines targeting and conditional activation of CD40 and 4-1BB on immune cells for priming and (re-) activation of tumor-specific immune responses. We previously showed that GEN1042 induces conditional CD40 and 4-1BB agonist activity, leading to dendritic-cell maturation and enhanced T-cell activation and effector functions in vitro. However, dysfunction of exhausted T cells in the solid tumor microenvironment may represent a potential resistance mechanism to checkpoint inhibitors/agonists. Here we utilized a multi-omics approach to evaluate whether GEN1042 could reverse T-cell exhaustion in vitro. Publicly available single cell RNA sequencing datasets were harmonized across multiple solid-tumor indications (including treatment-naïve and anti-PD-1 and/or anti-CTLA-4 pretreated samples) and analyzed for expression of CD40, 4-1BB and PD-1 on various immune-cell subsets based on their transcriptomic signatures to characterize target prevalence. In vitro mixed lymphocyte reaction (MLR) functional assays were performed where unstimulated healthy donor CD3+ T cells or CD3+ T cells exhausted by repeated stimulation with anti-CD3/CD28 beads were co-cultured with allogeneic lipopolysaccharide (LPS)-matured dendritic cells. Cultures were analyzed for cytokine secretion and expression of cell surface proteins. In the unstimulated T cell/mDC MLR assay, concurrent treatment with GEN1042 and PD-1 blockade potentiated IFNγ, TNFα and IL-2 production compared with either compound alone. In the T-cell exhaustion MLR assay, T cells showed increased expression of inhibitory receptors (e.g., TIM-3, LAG-3) and exhibited hyporesponsiveness for both proliferation and cytokine secretion upon restimulation with anti-CD3/CD28 beads. Here, the combined functional effect of GEN1042 plus PD-1 blockade further potentiated IFNγ secretion compared to single agent activity and induced IL-2 at similar levels to that observed for GEN1042 alone. These data suggest that, in addition to enhancing T-cell effector functions during T cell priming, GEN1042 can amplify the magnitude of the immune response in combination with PD-1 blockade by re-establishing the functional activity of dysfunctional T cells. GEN1042 is currently being evaluated in patients with advanced solid tumors in a phase 1/2 clinical trial (NCT04083599). Citation Format: Vanessa M. Spires, Gregg Masters, Christina Yu, Matt Hancock, Monique N. Luijten, Alexander Muik, Kristina Nuermberger, Friederike Gieseke, Tahamtan Ahmadi, Özlem Türeci, Maria Jure-Kunkel, Ugur Sahin, Mark Fereshteh, Homer C. Adams, Jordan M. Blum. GEN1042 (DuoBody-CD40x4-1BB)®in combination with PD-1 blockade reverses T-cell exhaustion in vitro [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3281.

Pretreated banana peels as a source for the recovery of phenolic compounds: Extraction kinetics, ultrasound optimization, and conventional extraction methods

This study aimed to evaluate the recovery of polyphenols from pretreated banana peels by ultrasound-assisted extraction (UAE). The effects of temperature (40–60 °C) and ethanol concentration (40–80%) were investigated. First, the peels were pretreated with ethanol and ultrasound for 10 min to preserve the bioactive compounds during drying. The optimum extraction condition defined by the composite desirability was 52.30 °C and 60.10%, resulting in the maximum polyphenols recovery (355.11 ± 4.99 μgGAE g−1). These values were achieved by considering a short extraction time (5 min). The study also showed that UAE recovers higher levels of polyphenols and flavonoids than conventional extraction techniques (Soxhlet and hydrodistillation). In general, with eco-friendly solvents and pretreated samples, the UAE can recover significant amounts of bioactive compounds in short run times, providing a viable option for using this waste.

Understanding the Inhibition Mechanism of Lignin Adsorption to Cellulase in Terms of Changes in Composition and Conformation of Free Enzymes

The adsorption of lignin to cellulase is the major obstacle in the sugar-platform conversion of lignocellulosic bioresources. In this study, the adsorption behavior of untreated and pretreated lignin samples from corn stover to cellulase was investigated, in particular the effects of lignin adsorption on the composition and spatial conformation of free enzymes were explored. The results showed that pretreatments decreased the hydrophobic groups contents of lignin, i.e., aromatic ring, ether and carbonyl, as well as the content of ionizable group, i.e., carboxyl, which reduced its hydrophobicity and negative charge density, thus weakening the adsorption ability of lignin to cellulase. The lignin samples mainly adsorbed the CBHII component of cellulase to inhibit the synergistic effect of free enzymes. Lignin adsorption altered the spatial position of tryptophan residues in free enzymes, exposing them to the protein surface. In addition, the secondary structure of free enzymes was altered, with a decrease in the alpha-helix content and an increase in the random coil content, thus loosening the spatial conformation of free enzymes. The change degree in the spatial structure of free enzymes correlated with the adsorption capacity of the lignin, i.e., lignin with low adsorption capacity caused the least damage to free enzyme, with NaOH pretreated lignin being the best. It appears that appropriate pretreatment and chemical modification of enzymes to resist lignin adsorption is a promising long-term pathway to overcome the lignin inhibition during sugar-platform conversion of lignocellulosic bioresources.

Effect of Calcium and Osmotic Pretreatments on Mass Transfer and Texture Parameters during Processing of Chilacayote (Cucurbita ficifolia Bouché)

The aim of this work was to analyze the effect of calcium and osmotic pretreatments on mass transfer and texture parameters of chilacayote (Cucurbita ficifolia Bouché). Samples were immersed in Ca(OH)2 solutions at concentrations of 0.5, 1, and 1.5 g/100 mL water; solution temperature of 20, 35, and 50 °C; and immersion times of 1.5, 3, and 4.5 h. Subsequently, pretreated samples with a Ca solution were osmotically dehydrated for 2 h with sucrose solutions at 30, 45, and 60 °Brix and temperatures of 30, 50, and 70 °C. Chilacayote tissue showed a positive response to interaction with Ca2+ ions, increasing the calcium content in the samples. The osmotic effect increased the water loss and the solute gain in the calcium impregnated samples. However, the calcium gained was leached, so the calcium retained decreased considerably. The hardness and adhesiveness increased significantly during calcium pretreatment, and it was maintained during osmosis by impregnated sucrose on the surface. Also, calcium increased the cohesiveness, but its values decreased after osmosis due to brittle behavior acquired. Samples acquired a more plastic than elastic behavior because the springiness decreased during both pretreatments. The gumminess and chewiness were affected by the decrease in cohesiveness and springiness, so less work is required to digest the osmosed samples. Calcium pretreatment (1 g/100 mL water, 35 °C, and 3 h) and osmosis (45 °Brix, 50 °C, and 2 h) were selected as appropriate process conditions for adequate calcium content, mass transfer, and texture parameters.

EFFECT OF DIFFERENT CHEMICALS ON THE CARBONIZATION BEHAVIORS AND POLLUTION REMOVAL PERFORMANCE OF BIOCHAR ADSORBENTS DERIVED FROM TEXTILE WASTE

One of the smart methods of controlling the increasing demand for raw materials and environmental pollution is the recycling of waste. In this study, optimum conditions were determined for the conversion of wastes that will not be reused in the textile industry into functional activated carbon. For this, raw and Fe, H2SO4, H3PO4 impregnated textile wastes were carbonized at different temperatures for varying times. The molecular structure and crystal lattice of the prepared activated carbons were investigated by FT-IR and XRD analyzes, respectively. SEM and BET analyzes were used to examine the morphology and surface properties of the samples. The existence of C=C, C=O, and C–O–C functional groups was recognized by the vibrations at around 1300-1700 cm-1. A well-crystalline and porous structure was formed as a result of the carbonization of the Fe and H3PO4 pretreated samples, while the process was conducted at a lower temperature due to the catalytic effect. 25–85 mg/g methyl orange (MO) and industrial textile water (ITW) removal capacity were recorded for all samples. Efficient biochars were obtained by carbonization of waste materials while protecting the environment. Such a specific approach could be developed for each waste material for environmental and economic production

Investigation of Microplastics (≥10 μm) in Meconium by Fourier Transform Infrared Microspectroscopy.

Microplastics are prevalent emerging pollutants with widespread distribution in air, land and water. They have been detected in human stool, blood, lungs, and placentas. However, human fetal microplastic exposure remains largely under-studied. To assess fetal microplastic exposure, we investigated microplastics using 16 meconium samples. We used hydrogen peroxide (H2O2), nitric acid (HNO3) and a combination of Fenton's reagent and HNO3 pretreatment methods respectively to digest the meconium sample. We analyzed 16 pretreated meconium samples with an ultra-depth three-dimensional microscope and Fourier transform infrared microspectroscopy. The result showed that H2O2, HNO3 and Fenton's reagent combined with HNO3 pretreatment methods could not digest our meconium samples completely. Alternatively, we developed a novel approach with high digestion efficiency using petroleum ether and alcohol (4:1, v/v), HNO3 and H2O2. This pretreatment method had good recovery and non-destructive advantages. We found no microplastics (≥10 μm) in our meconium samples, indicating that microplastic pollution levels in the fetal living environment are miniscule. Different results between previous studies' and ours underscore that comprehensive and strict quality control are necessary for further studies on microplastic exposure using human bio-samples.