Alkaline Extraction Research Articles

Pharmaceutical Assessment of the Impact of the Method of Extraction on the Suitability of Pectin from Plantain (Musa paradisiaca) Peels as a Suspending Agent in Oral Liquid Formulations.

Natural polymers such as pectin have gained increased utilization in pharmaceutical and biotechnology sectors because they are affordable, easily accessible, nontoxic, and chemically modifiable, with the potential to be biodegradable and biocompatible. Musa paradisiaca (plantain) peels make up 30-40% of the overall weight of the fruit. The extraction of pectin from these residues can therefore be viewed as a possible waste of wealth. This study, therefore, focused on evaluating the suspending properties of pectin obtained from Musa paradisiaca (plantain) peels (through acid and alkaline extraction) and presented an alternative suspending agent in the pharmaceutical formulation of suspensions. The unripe peels of Musa paradisiaca were acquired and authenticated at the Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana. Pectin was extracted from the peels using both acid and alkaline extraction processes, respectively, characterized, and evaluated for its phytochemical properties. Different concentrations of the acid and alkaline pectin extracts were employed as a suspending agent in paracetamol suspensions, using acacia gum as a standard. The pectin yields obtained were 4.88% and 7.61% for the acid and alkaline extraction processes, respectively, while phytochemical screening revealed the presence of glycosides, tannins, saponins, and phenols in both extracts. The alkaline pectin extract recorded higher equivalent weight, degree of esterification, ash content, and crude content than the acid pectin extract, while FTIR identified similar functional groups in both acid and alkaline pectin extracts. The test suspensions reported significant differences (P < 0.05) in flow rates, ease of redispersion, sedimentation volumes, and rates compared with acacia gum. Moreover, when the acid and alkaline pectin extracts were compared, significant differences (P < 0.05) were observed in sedimentation rates and sedimentation volumes, suggesting that the extraction method may affect suspending properties. Ultimately, the alkaline pectin extract had better suspending properties than the acid pectin extract; however, they both can be used as an alternative to acacia gum as a suspending agent.

Synthesis of Cu-Al layered double hydroxides from aluminum saline slags

The use of saline slag, a hazardous waste generated during the recycling of aluminum, as aluminum source for the synthesis CuAl layered double hydroxides (LDH) is for the first time reported in this study. Due to the Jahn-Teller effect, divalent copper–aluminum LDH come usually with impurities and a pure CuAl LDH is not easy to obtain. The effect of synthesis pH has been examined by comparing LDH synthesized at various pH, ranging from 6 to 12 via a co-precipitation method using aluminum obtained from an alkaline extraction of the slag. For comparison purposes, a sample was synthesized at pH = 9 using commercial aluminum Al(NO3)3·9H2O instead of extracted aluminum. The effects of the aging time and calcination temperature are also discussed. The LDH and their calcined metal mixed oxide (layered double oxide, LDO) have been analyzed with several characterization techniques: powder X-ray diffraction (PXRD), N2 adsorption at −196 °C, thermogravimetric analysis (TGA), temperature programmed reduction (TPR), scanning electron microscopy (SEM), transmission electron microscopy and energy-dispersive X-ray spectroscopy (TEM and EDS). Synthesis pH has been proved not only to have a significant effect on the nature of secondary phases but also on the structure and morphology of the samples.

Protein Quality Characterization of Defatted White Sesame Cake and Its Protein Isolate

Present work evaluated the protein quality of defatted white sesame flour and the protein isolates obtained from sesame cake through the alkaline extraction at a pH 9.5. The study was conducted at Department of Foods and Nutrition, Post Graduate and Research Center (PGRC), College of Community Science and MFPI - Quality Control Laboratory, Professor Jayashankar Telangana State Agricultural University, Rajendranagar, Hyderabad (India) during 2021-2023. Defatted white sesame cake was subjected to alkaline extraction at pH 9.5 and resultant isolates were evaluated for nutrient composition, scanning electron microscope imaging, amino acid composition and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The obtained data was subjected to one-way analysis of variance. The white sesame protein isolates had a protein content of 93.83%, isolate recovery of 37.00 g/100 g and protein yield of 71.77%. The non-essential amino acids (NEAAs) content of the defatted white sesame flour and white sesame protein isolates ranged between 68.06% to 70.60% of the total protein content, while 29.40% to 31.94% was essential amino acids (EAAs). Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of defatted white sesame flour WSF and white sesame protein isolate (WSPI) exhibited protein bands within the molecular weight range of 20 to 62 kDa. The protein isolates derived from sesame seed cake has promising potential for integration into diverse food formulations, offering an avenue to combat protein deficiencies.

Implications of Particle Size in the Extraction of Cellulose from the Calamagrostis Intermedia Species

This research aimed to elucidate the implications of particle size on cellulose extraction from the species Calamagrostis intermedia, endemic to Ecuador. Within the versatile cellulose extraction and trade industry, using timber sources results in a relentless environmental impact, mainly when no resource rationing occurs during the washing or bleaching phases. The investigation incorporated a sample pretreatment encompassing a drying, grinding, and sieving study, followed by an alkaline extraction. The study found that particle size significantly affected the quantity of fiber and cellulose pulp extracted from samples previously dried at 65°C with particle sizes of 300 and 106 μm. Characterization tests revealed variations in the color and texture of the extracted cellulose, attributable to an ineffective delignification stage within the fiber bleaching process. Variations in molecular weight corresponding to 126.32 x 103 g/mol were identified among samples, and FTIR analysis presented a syringyl ring and lignin stretching. Optical microscopy exposed the absence of well-defined regions in the fibers and a readily observable crystalline network. In conclusion, particle size critically influences cellulose extraction from Calamagrostis intermedia, impacting the yield and properties of the resultant product, indicating that further optimization of the extraction and delignification process is required to enhance the quality of the extracted cellulose. Keywords: Calamagrostis intermedia; Particle Size; Cellulose Extraction

Improved protein extraction technology using deep eutectic solvent system for producing high purity fava bean protein isolates at mild conditions

This study aimed to extract fava bean proteins using an eco-friendly deep eutectic solvent (DES) containing choline chloride and a glycerol-based system. Protein extraction conditions were optimized using response surface methodology, and the extracted protein was characterized in comparison to the protein extracted using a conventional alkaline solution. The optimum conditions obtained using the RSM model were: 28:1 w/w liquid: solid ratio, 1:2 w/w choline chloride: glycerol molar ratio, 50 °C temperature, 1 h extraction time, and 40% w/w water content. Under these optimum conditions, protein content, protein yield, and protein recovery rates of 92.33 ± 2.28%, 65.42 ± 6.53%, and 23.15 ± 2.31% were achieved. Alkaline extraction showed similar protein content (92.50 ± 1.36%) but lower protein yield (60.76 ± 1.16%) and recovery rate (21.74 ± 0.19%) when compared to DES-extracted proteins (P < 0.05). The secondary structure analysis revealed an increased α-helix (21.37%) content in DES-extracted proteins compared to alkaline-extracted proteins (10.68%). Moreover, the alkaline-extracted proteins showed intermolecular β sheets as protein aggregates (7.61%) and an increased percentage of β-turns (19.71%). The molecular weight distribution pattern of proteins extracted from both methods showed more similarities. Overall, DES protein extraction could be an alternative to the conventional alkaline extraction method, promoting sustainable plant protein production from fava beans for use in new food formulations.

Characterization of alginate from Antarctic Himantothallus grandifolius (Phaeophyceae) and preparation of polyelectrolyte complexes with chitosan

AbstractHydrogels are three‐dimensional polymeric materials with applications in various areas such as biomedicine, tissue engineering, pollutant capture systems, and so forth. However, its application is limited due to the reproducibility of its properties. Factors such as the composition of the constituents, the type of union between the polymer chains, and the crosslinking time play a crucial role in ensuring its reproducibility. In this study, the objective is to prepare a matrix with well‐defined properties that ensure controlled release processes. Treatment of Himantothallus grandifolius with Na2CO3 aqueous solution afforded in 18.9% yield alkaline extract. Hydrogels were prepared by ionic complexation of alginate from H. grandifolius, and polyguluronate enriched alginate from Desmarestia ligulata with chitosan stabilized by immersion in 0.1 M CaCl2 solution; better swelling ratio in water was found for hydrogels with low molecular weight chitosan (MW 125,000 g/mol) than those with medium molecular weight chitosan (MW450,000–500,000 g/mol). Liberation of the model drug metformin hydrochloride from alginates: chitosan complexes (3:1) at pH 1.5 was especially low for hydrogel from H. grandifolius during the first 2 h; 70% of metformin was released at pH 6.5 after 24 h. This polyelectrolyte complex constitutes a good material for potential application in biomedicine considering its cationic and anionic characteristics.

Ultrasound and enzyme‐pretreated extraction for the valorization of pea pod proteins

AbstractPea pod (PP) is an agricultural by‐product with 10%–13% protein content which has a potential to be converted to value‐added ingredients. In this study, different protein extraction strategies including three different solvents (water, salt, and alkaline) and two different pretreatments (ultrasound [US] and enzyme such as pectinase and Viscozyme®) before conventional alkaline extraction were employed to maximize the extraction yield. The US‐pretreated alkaline extraction achieved the highest yield (21.1%) in protein extracts under optimum conditions (30% amplitude for 5 min). PP protein concentrates showed significant differences in solubility, sodium dodecyl sulfate–polyacrylamide gel electrophoresis protein patterns, scanning electron microscopy images, and color depending on the applied extraction method. All PP residues after extraction still remained protein (5.2–8.0 g/100 g) regardless of the extraction techniques, representing the challenges in protein extraction from agricultural by‐products with a lignocellulosic matrix. The combined use of US and enzyme treatments should be further investigated for higher extraction yields.Practical ApplicationsAgricultural wastes and by‐products could be potential protein sources; however, their lignocellulosic structure could be challenging for protein extraction. In the current study, different extraction strategies including ultrasound (US) and enzyme pretreatments were performed for the extraction of proteins from pea pods which is an agro‐industrial by‐product. Results suggest that US pretreatment may have promising applications for the extraction of valuable compounds from agricultural and industrial by‐products, contributing to sustainable food processing strategies.

Impact of Six Extraction Methods on Molecular Composition and Antioxidant Activity of Polysaccharides from Young Hulless Barley Leaves.

Young hulless barley leaves are gaining recognition for potential health benefits, and the method of extracting polysaccharides from them is critical for potential food industry applications. This study delves into a comparative analysis of six distinct fiber extraction techniques: hot water extraction; high-pressure steam extraction; alkaline extraction; xylanase extraction; cellulase extraction; and combined xylanase and cellulase extraction. This analysis included a thorough comparison of polysaccharide-monosaccharide composition, structural properties, antioxidant activities (DPPH, ABTS, and FRAP), and rheological properties among fibers extracted using these methods. The results underscore that the combined enzymatic extraction method yielded the highest extraction yield (22.63%), while the rest of the methods yielded reasonable yields (~20%), except for hot water extraction (4.11%). Monosaccharide composition exhibited divergence across methods; alkaline extraction yielded a high abundance of xylose residues, whereas the three enzymatic methods demonstrated elevated galactose components. The extracted crude polysaccharides exhibited relatively low molecular weights, ranging from 5.919 × 104 Da to 3.773 × 105 Da across different extraction methods. Regarding antioxidant activities, alkaline extraction yielded the highest value in the ABTS assay, whereas enzymatically extracted polysaccharides, despite higher yield, demonstrated lower antioxidant capacity. In addition, enzymatically extracted polysaccharides exerted stronger shear thinning behavior and higher initial viscosity.

Modification of sunnhemp (Crotalaria juncea) protein isolate by high intensity ultrasound: Impact on the molecular structure, amino acid composition and nutritional profiling

In the present study, sunnhemp protein isolate (SHPI) was prepared by alkaline extraction followed by acid precipitation method. The prepared sunnhemp protein isolate was subjected to high-intensity ultrasound treatment at 40 and 50% ultrasound amplitude for 10, 20, and 30 min. The effect of ultrasound treatment on molecular flexibility, available lysine content, antioxidant properties, and molecular weight distribution was investigated. The antioxidant activity of ultrasound treated SHPIs was found to be higher than the untreated sample. The optimum ultrasound treatment condition (50% amplitude and 20 min) had the highest molecular flexibility and antioxidant properties among all the sunnhemp protein isolates. The available lysine content of all SHPI samples decreased after ultrasound treatment. SDS-PAGE results demonstrated that there was no change in the electrophoresis patterns of ultrasound treated SHPI samples over the untreated sample, thus indicating the primary structure of the sunnhemp protein isolate was intact. Hydrophobic amino acid content was improved after ultrasound treatment in US5 (50% amplitude for 20 min) sample, thereby resulting in increase in total amino acid content than SHPI without ultrasound treatment. Biological value and essential amino acid index were also improved due to ultrasound treatment in US5 sample. Leucine and isoleucine were the first and second limiting amino acids found in SHPI according to FAO/WHO scoring patterns. Overall, it can be concluded that ultrasound treated SHPI can be a valuable source of plant-based protein with desirable nutritional characteristics at a low cost. The current findings speculated that high-intensity ultrasound treatment can be a valuable technique for the modification of sunnhemp protein isolate with its promising utilization in food supplements.

Application of a modified method of humic acids extraction as an efficient process in the production of formulations for agricultural purposes

Abstract Due to their properties, humic acids (HA) can interact with macro- and micronutrients and retain plant nutrients in the soil profile. The aim of the presented work was to develop a new integrated 4-step process for the isolation of humic acids from peat with their simultaneous enrichment in macronutrients. The study demonstrated the possibility of replacing traditional solutions used in the extraction of humic acids with solutions that are a source of macronutrients. For the alkaline extraction step, a process assisted with ultrasound was implemented, which allowed to increase the efficiency of humic acids isolation. Optimization of this step has shown that, with the application of ultrasound in the new procedure, it is possible to obtain the humic acids isolation efficiency of more than 60%. The qualitative analysis of the products obtained confirmed the presence of structures characteristic of humic acids, including key functional groups.

Comparative evaluation of milk proteins and oil-seed-cake-derived proteins extracted by chemical and biological methods for obesity management.

In light of the exponential rise in global population, there is a critical requirement to reduce food waste on a global scale. According to studies, agricultural wastes such as oil-seed cakes offer great nutritional value. Acid precipitation (A) and alkaline extraction methods (traditional methods) were used to extract protein from oil-seed cakes; however, both procedures are linked to decreased protein quality and quantity, which prompted the development of a novel strategy known as the biological/microbial/probiotic (B) method. Therefore, the present study aimed to highlight the optimal way of protein extraction from oil-seed cakes and the effect of extraction methods on protein efficacy against obesity. The outcomes were also compared with milk proteins. In vitro study provided evidence that proteins from both sources (plant and milk) suppressed adipogenesis and stimulated adipolysis in 3T3L-1 cells. For the in vivo study, mice were fed with different protein extracts: soya protein preparation (SPP), ground protein preparation (GPP), whey protein (WP) and casein protein (CP) containing 40% of their calories as fat. Body weight decreased significantly in all the rats except CP-fed rats. Body mass index, atherogenic index, plasma triglyceride and very-low-density lipoprotein cholesterol level decreased significantly in all the groups in comparison to the model group (high-fat-diet group), but the decrease was more pronounced in plant proteins than milk proteins. In hepatocytes, the expression of fasting-induced adipose factor, carnitine palmitoyltransferase I and peroxisome proliferator-activated receptor α genes was increased significantly in SPP-fed groups. Adiponectin gene expression was upregulated significantly in visceral fat tissue in groups fed SPP-B, GPP-A and CP, whereas leptin gene was downregulated significantly in all groups except SPP-A. This study demonstrates that SPP-B showed the most effective anti-obesity property, followed by WP. Additionally, we found that the biological precipitation approach produced better outcomes for plant proteins isolated from oil-seed cakes than the acid precipitation method. © 2023 Society of Chemical Industry.

Glycome profiling and immunohistochemistry uncover changes in cell walls of Arabidopsis thaliana roots during spaceflight

A large and diverse library of glycan-directed monoclonal antibodies (mAbs) was used to determine if plant cell walls are modified by low-gravity conditions encountered during spaceflight. This method called glycome profiling (glycomics) revealed global differences in non-cellulosic cell wall epitopes in Arabidopsis thaliana root extracts recovered from RNA purification columns between seedlings grown on the International Space Station-based Vegetable Production System and paired ground (1-g) controls. Immunohistochemistry on 11-day-old seedling primary root sections showed that ten of twenty-two mAbs that exhibited spaceflight-induced increases in binding through glycomics, labeled space-grown roots more intensely than those from the ground. The ten mAbs recognized xyloglucan, xylan, and arabinogalactan epitopes. Notably, three xylem-enriched unsubstituted xylan backbone epitopes were more intensely labeled in space-grown roots than in ground-grown roots, suggesting that the spaceflight environment accelerated root secondary cell wall formation. This study highlights the feasibility of glycomics for high-throughput evaluation of cell wall glycans using only root high alkaline extracts from RNA purification columns, and subsequent validation of these results by immunohistochemistry. This approach will benefit plant space biological studies because it extends the analyses possible from the limited amounts of samples returned from spaceflight and help uncover microgravity-induced tissue-specific changes in plant cell walls.

Thermal Gelation of Proteins from Cajanus cajan Influenced by pH and Ionic Strength.

Cajanus cajan [pigeon pea (PP)] is an important legume crop for subsistence agriculture and its seeds are an alternative plant-based protein source. PP protein isolates (PPI) are able to form heat-induced gels that could be used for food applications. The aim of this work was to study the influence of pH (2.1, 3.9, 6.3, and 8.3) and ionic strength (μ) (0.10 and 0.54) on thermal stability and thermal gelation of PPI obtained by alkaline extraction (pH8.0) and isoelectric precipitation. Thermal stability of PPI changed with pH variation at low ionic strength (μ = 0.10), decreasing this dependence with the increase of ionic strength (μ = 0.54). At μ = 0.10, gelation capacity of PPI was lower at pH2.1 and pH3.9. These gels presented a coarse network, which entails low WHC. At pH6.3 and pH8.3, gels showed a solid-like character with a compact and homogeneous matrix, with better WHC. At μ = 0.54, gel formation was favoured at pH2.1 and pH3.9. G'20/G'95 ratio values and differential solubility results suggest that hydrogen bonds and electrostatic interactions could play an important role in gel formation at pH6.3 and pH8.3.

Impact of extraction conditions and seed variety on the characteristics of pennycress (Thlaspi arvense) protein: a structure and function approach

AbstractAs the consumer demand for plant proteins continues to grow, the food industry is seeking novel and sustainable protein sources to incorporate in various food products. Pennycress (Thlaspi arvense), a sustainable cover crop, produces oilseeds high in protein, warranting investigation. Accordingly, protein extraction from pennycress was evaluated under various extraction conditions, using alkaline extraction and salt solubilization coupled with ultrafiltration. Given the superior color and functionality of the salt extracted pennycress protein isolate (PcPI), its production was scaled‐up about two hundred folds in a pilot plant. Furthermore, a new pennycress accession bred to have zero erucic acid (0EA) was evaluated to determine the impact of seed variety on protein characteristics. Structural and functional characterization was performed on PcPI and compared to native (nSPI) and commercial (cSPI) soy protein isolates. Salt extracted PcPI had comparable gel strength to cSPI, three times higher solubility under acidic conditions, and ~1.5 times better emulsification capacity. PcPI extracted from 0EA was mildly different in structure and functionality from that extracted from wildtype pennycress, with the slight variation attributed to genetic variance. Finally, the protein digestibility‐corrected amino acid score (PDCAAS) of the salt extracted PcPI, calculated in vivo (0.72) and in vitro (0.87), was superior or comparable to other plant protein sources. This research provided, for the first time, a comprehensive evaluation of different protein extraction protocols to produce a functional PcPI that can compete with soy protein for various food applications, such as acidic beverages, meat and dairy products, and emulsified systems.

Ultrasonic-aided extraction and degossypolization of cottonseed meal protein: Optimization and characterization of functional traits and molecular structure

Cottonseed meal (CM) is a useful protein resource, but the presence of gossypol (a toxic compound) limits it utilization in industry. To reduce the gossypol content, the use of ultrasonication in extracting protein from CM was explored. Following single-factor experiments, operative limits of independent variables affecting removal ratio of total-gossypol (RRTG) and extractability of CM protein (CMP) were achieved as temperature (35–55 °C), sonication power (250–350 W), time (12–24 min), and NaOH concentration (2–6 g/L). Box-Behnken’s Design centered on a 3–level-4–factor was employed to optimize ultrasonication conditions on the yield and RRTG of CMP. The predictive models were statistically adequate (p < 0.0001) to reflect the experimental results of the responses as verified by insignificant lack-of-fit (p ≥ 0.1333) and high coefficient of determination (R2 ≥ 0.976) values. The optimized sonication conditions for two responses were 53 °C, 320 W, 21 min, and 4.6 g-NaOH/L. Under optimized conditions, the observed removal ratio of free- and total-gossypol and yield values were 93.21 %, 87.56 %, and 58.23 %, which substantially increased by 15.64 %, 12.88 %, and 29.56 %, respectively over control (alkaline extraction). Furthermore, sonicated isolate showed an increase in solubility and emulsion property relative to control, buttressed by particle sizing and zeta potential outcomes. Sodium dodecyl sulfide polyacrylamide gel electrophoresis (SDS-PAGE), Fourier Transform Infrared (FTIR) spectroscopy, atomic force microscopy (AFM), and amino acid data showed notable changes in molecular weight, functional groups, surface topography, and hydrophobic amino acid content of CMP, respectively (i.e., after sonication), suggesting partial unfolding in CMP conformation. Accordingly, CMP isolates (especially the sonicated protein) could be considered edible because of the observed low gossypol content (< 0.045 %) and thus can be utilized as natural additives in food formulations.

Chayote (Sechium edule (Jacq.) Swartz) Seed as an Unexploited Protein Source: Bio-Functional and Nutritional Quality of Protein Isolates.

Chayote seeds have good protein quality and recognized bioactive properties, being still unexplored as a nutraceutical. In this work, chayote seed protein isolates (CSPIs) were prepared by alkaline extraction (AE) and ultrasonic-assisted extraction (UAE) using a probe (20 kHz) or a water bath (40 kHz), and their physicochemical, functional properties and nutraceutical potential were investigated. For all treatments, protein solutions (10% w/v) were treated for 20 min. The UAE significantly (p < 0.05) improved the protein extraction yield and functional properties (protein solubility, turbidity, and emulsifying and foaming properties) of CSPIs. This effect was more pronounced using a probe sonication device. The CSPI obtained by UAE-20 kHz contained 8.2 ± 0.9% dw of proteins with a balanced amino acid profile, higher content of essential amino acids (315.63 mg/g of protein) and higher protein digestibility (80.3 ± 4.5%). Furthermore, CSPI.UAE-20 kHz exhibited the highest phenolic content (7.22 mg GAE/g dw), antioxidant capacity and α-amylase inhibition (74%, at 100 μg/mL concentration). Overall, these results suggest that ultrasound technology contributed greatly to the corresponding functional and nutritional properties of chayote seed proteins. It would be, therefore, useful to apply this Cucurbitaceae species in food systems, promoting its nutritional and commercial value.

A SP-ICP-MS protocol for the detection of metal nanoparticles composition and size in tattooed ex vivo human skin explants

We developed and validated a protocol based on Single Particle Inductively Coupled Plasma Mass Spectrometry (SP ICP-MS) to detect composition and size of metal nanoparticles (MNPs) in tattoo inks end ex vivo tattooed human skin explants. The explants were tattooed with different inks using an ordinary tattoo machine. Then, 72 hours after tattooing, skin explants were subjected to alkaline extraction by tetramethylammonium hydroxide solution and MNPs of Ag, Al2O3, Au, Cr2O3, CuO, Fe2O3, TiO2 and ZnO were analysed for particle composition and size by SP ICP-MS. The method was validated by assessing the limit of detection, accuracy, precision, and size stability over 72 hours. Particles of Al2O3, Cr2O3, CuO, Fe2O3, TiO2 and ZnO were observed in human skin in the range from 27 nm to 153 nm, and from 26 nm to 228 nm in tattoo inks. Ag and Au NPs were not found neither in inks nor in the skin. Advantages of the protocol were the ability to simultaneously detect the composition of particles and their size, the straightforward sample preparation, the high sensitivity and precision, and the speed of execution of the analysis. The developed methodology can be applied to skin exposed to other consumer products topically applied, such as sunscreens, cosmetics, personal care products and medical devices, which can be all sources of MNPs, in order to improve knowledge and support the human exposure assessment process.

Arabinoxylan from Corn Fiber Obtained through Alkaline Extraction and Membrane Purification: Relating Bioactivities with the Phenolic Compounds.

Arabinoxylan has prebiotic properties, as it is able to resist digestion in the small intestine and undergoes fermentation in the large intestine. In this work, arabinoxylan was extracted from corn fiber using an alkaline solution and further purified with membrane processing. It was found that the extracts were mainly composed of xylose (50-52%), arabinose (37-39%), galactose (9%) and glucose (1-4%), with an A/X ratio of 0.72-0.77. All the extracts were composed of phenolic compounds, including ferulic acid derivatives such as dimers, trimers and tetramers. The purified extract had a lower concentration of ferulic and p-coumaric acid (0.004 and 0.02 mg/mgdry_weight, respectively) when compared to raw extract (19.30 and 2.74 mg/mgdry_weight, respectively). The same effect was observed for the antioxidant activity, with purified extracts having a lower value (0.17 ± 0.02 µmol TEAC/mg) when compared to the raw extract (2.20 ± 0.35 µmol TEAC/mg). The purified extract showed a greater antiproliferative effect against the HT29 cell line with EC50 = 0.12 ± 0.02 mg/mL when compared to the raw extract (EC50 = 5.60 ± 1.6 mg/mL). Both raw and purified extracts did not show any cytotoxicity to the Caco-2 cell line in the maximum concentration tested (10 mg/mL).

Regeneration possibilities and application of magnetically modified biochar for heavy metals elimination in real conditions

Although new types of composites with magnetic properties and high adsorption capacity for potentially toxic elements elimination are studied by researcherers, the information about the reusability, stability and removal efficiency of composites is still scarce or absent. Therefore, the aim of our work was applicate the sorbent to eliminate Zn(II), Cd(II) and Pb(II) ions from industrial waste leachates, and moreover, study the composite reusability and magnetic separation efficiency. Magnetically modified biochar was prepared from the fermentation residue of maise hybrid by a simple two-step method with microwave assistance. Composite properties, as well as the adsorption efficiency and magnetic response are depend on the extraction agent. The alkaline extraction agent showed the best properties for reusability and had no influence on Fe releasing from the composite, the adsorption efficiency was higher than 90% even in the 5th recycling cycle, and the composite remained magnetically active. The separation efficiency of composite from an aqueous environment by a magnet was higher than 95% within 15 min. Magnetically modified biochar proved to be an effective sorbent for metal ions elimination from wastewater.

Continuous counter-current electrophoretic separation of oleosomes and proteins from oilseeds

Oilseeds, with their high content of oil and protein, will play an important role in the transition to plant based foods. Currently, seed oil extraction involves elevated temperatures and the use of organic solvents, which degrade the quality of both oils and proteins. To take full advantage of the oilseeds, a gentler process is needed. We here propose a mild alkaline extraction followed by a continuous electrophoretic separation process that is based on differences in electrophoretic mobility and recovers intact oleosomes and proteins from the seeds. Rapeseed oleosomes and proteins are both negatively charged at pH ≥ 5, yet exhibit significantly different electrophoretic mobility. Therefore, separation can be achieved by imposing a counter-current hydrodynamic flow rate between their electrophoresis rate. Thus, the compounds with higher mobility, oleosomes, are retained by the electric field, and the compounds with lower mobility, proteins, go along with the flow. The separation was modeled using the Nernst-Planck equation and demonstrated using a PDMS-based microfluidic system. Both the modeling and the experimental studies confirmed that the direction and rate of migration of the compounds can be steered by the electric field strength and the convective flow velocity. The proposed electrophoretic approach is feasible and scaleable, and may be a novel path to separate differently charged components under mild conditions, thereby preserving their original native properties.