Acid Hydrolysis Research Articles

Polyhydroxylated Sirostanol Saponins from the Rhizomes of Paris dulongensis.

Three new polyhydroxylated spirostanol steroidal saponins, dulongenosides B-D (2-4), along with 14 known compounds, dulongenoside A (1), padelaoside B (5), parisyunnanoside G (6), polyphyllin D (7), ophiopogonin C' (8), formosanin C (9), dioscin (10), paris saponin VII (11), paris H (12), parisyunnanoside I (13), protodioscin (14), proprotogracillin (15), crustecdysone (16), and stigmasterol-3-O-β-d-glucopyranoside (17), were isolated from the rhizomes of Paris dulongensis (Melanthiaceae). Their chemical structures were elucidated based on extensive analyses of NMR and MS data and acidic hydrolyses. The isolates were evaluated for their cytotoxicity to five human cancer cell lines (HL-60, SW480, MDA-MB-231, A549, and A549/Taxol) and the normal human bronchial epithelial cell line BEAS-2B by the MTS test. Compounds 7-12 and 14 showed cytotoxic activity, with IC50 values ranging from 0.20 to 4.35 μM. Proprogracillin selectively inhibited A549(IC50 = 0.58 μM) and A549/Taxol (IC50 = 0.74 μM) cells, with no significant cytotoxic activity against HL-60, SW480, MDA-MB-231, or BEAS-2B cells, with IC50 values greater than 40 μM.

Cellulose Nanocrystals and Lignin Nanoparticles Extraction from Lemna minor L.: Acid Hydrolysis of Bleached and Ionic Liquid-Treated Biomass

Cellulose Nanocrystals and Lignin Nanoparticles Extraction from Lemna minor L.: Acid Hydrolysis of Bleached and Ionic Liquid-Treated Biomass

ISOLATION, PURIFICATION AND PHYTOCHEMICAL SCREENING OF POLYSACCHARIDE FRACTIONS FROM APIUM GRAVEOLENS’ L. BOTANICAL FORMS

The study of natural polysaccharides is an important area of research due to their pharmacological effects, including antiviral activity and the ability to regulate metabolic disorders. In addition, these polymeric structures realize several properties (sorption, shaping, transport (and delivery systems), which increases the interest of scientists in their isolation and analysis. This study aims to comparatively investigate the polysaccharide fractions in different botanical forms of celery odouriferous. The objectives of the study include the isolation of polysaccharide fractions, their purification by the Sevag method, estimation of monomeric composition of the fractions after acid hydrolysis by the HPTLC method, and determination of structural characteristics of the molecules by IR spectroscopy. Alcohol-soluble polysaccharides (ASPS), water-soluble polysaccharides (WSPS), and pectin substances (PS) were isolated from leaf, petiole, and root botanical forms of celery. After purification, the obtained substances were amorphous powders of light brown or light beige colour and odourless. The root botanical form of celery showed the highest yield of the target compounds (total (13.54±1.07)% after purification), while the petiole form (total (5.51±0.04)% after purification) showed the lowest yield. The monomeric composition of pectins and WSPS showed a predominance of galactose and arabinose, whereas the alcoholic ones showed a predominance of fructose and glucose. The interpretation of IR spectra showed the presence of absorption bands characteristic of free and bound carboxyl groups, C-O-C valence vibrations, α-configuration of the glycosidic bond, and C1-α-conformation of galacturonic acid in different polysaccharide fractions, which allows us to draw some conclusions regarding the structure of the substances. A comparative study of polysaccharide fractions of different botanical forms of odorous celery was carried out for the first time. Based on the results obtained, it is possible to single out WSPS and PS of celery root crops as the most promising phytosubstances for further development of products of functional, specialized nutrition and potential medicines on their basis. The methods of analysis used in the study can be proposed as part of the regulatory documentation for the control of these products.

Discovery of Potent Glycosidases Enables Quantification of Smoke-Derived Phenolic Glycosides through Enzymatic Hydrolysis.

When grapes are exposed to wildfire smoke, certain smoke-related volatile phenols (VPs) can be absorbed into the fruit, where they can be then converted into volatile-phenol (VP) glycosides through glycosylation. These volatile-phenol glycosides can be particularly problematic from a winemaking standpoint as they can be hydrolyzed, releasing volatile phenols, which can contribute to smoke-related off-flavors. Current methods for quantitating these volatile-phenol glycosides present several challenges, including the requirement of expensive capital equipment, limited accuracy due to the molecular complexity of the glycosides, and the utilization of harsh reagents. To address these challenges, we proposed an enzymatic hydrolysis method enabled by a tailored enzyme cocktail of novel glycosidases discovered through genome mining, and the generated VPs from VP glycosides can be quantitated by gas chromatography-mass spectrometry (GC-MS). The enzyme cocktails displayed high activities and a broad substrate scope when using commercially available VP glycosides as the substrates for testing. When evaluated in an industrially relevant matrix of Cabernet Sauvignon wine and grapes, this enzymatic cocktail consistently achieved a comparable efficacy of acid hydrolysis. The proposed method offers a simple, safe, and affordable option for smoke taint analysis.

Influence of acid hydrolysis on the degree of polymerization of cellulose from colored cotton substrates

This study investigated the influence of sulfuric acid hydrolysis on the cellulosic fibers and films’ degree of polymerization (DP). Cotton textile residues (dyed and white) and hydrophilic cotton were used as the raw material. The films were formed by the dissolution of fibers in ionic liquid and regeneration in water. Results showed that dyed cotton residues required hydrolysis at 0.5 M sulfuric acid for 30 min to achieve complete dissolution during viscosimetry assay. Due to different dyeing processes and chemical compositions, the color of the fibers influences the DP. Undyed samples submitted to hydrolysis had DP around 60% lower than samples without pretreatment. This effect was not observed when comparing films with and without hydrolysis, because the depolymerization occurs in the dissolution and regeneration step. This study expands the applicability of viscometry to colored substrates, serving as a starting point for future research on the impact of process parameters and dyes on cellulose polymerization.

Multiple effects of relative humidity on heterogeneous ozonolysis of cooking organic aerosol proxies from heated peanut oil emissions

The exposure to cooking organic aerosols (COA) is closely related to people's daily lives. Despite extensive investigations into COA's model compounds like oleic acid, the intricacies of heterogeneous ozonolysis of real COA and the effects of ambient conditions like humidity remain elusive. In this work, the ozonolysis of COA proxies from heated peanut oil emissions was investigated using diffuse reflectance infrared Fourier transform (DRIFTS) spectroscopy, and proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS). We found that humidity hinders the reaction between ozone and CC double bonds due to the competitive adsorption of water and ozone on COA. Although visible light has little influence on the ozonolysis of COA in the absence of humidity, the ozonolytic CO production is significantly promoted by visible light in the presence of humidity. It may be attributed to the formation of water-derived reactive oxygen species (ROS, mainly HO•) from the photosensitization of polycyclic aromatic hydrocarbons (PAHs) in COA. We also found that humidity can enhance the depolymerization of carboxylic acid dimers and hydrolysis of intrinsic acetals in the COA. Moreover, humidity promotes the release of VOCs during both the dark and light ozonolysis of COA. This work reveals the important roles of humidity-responsive and photo-responsive components in COA during its ozonolysis, and the change in VOC release may guide the control of human VOC exposure in indoor air.

Ultrafast catalytic reduction of organic pollutants using ternary zinc–copper–nickel layered double hydroxide

Water is the utmost essential commodity for the support of life process in animals. In recent decades, rapid industrialization and uncontrolled agricultural practices have led to increased level of toxic pollutants in groundwater, including organic pollutants (dyes, nitroarene compounds, antibiotics, etc.), inorganic pollutants (heavy metals, nanoparticles, etc.), and pesticides, posing a serious threat to human health and the environment. Although various technologies such as adsorption, photocatalysis, reverse osmosis, filtration, sedimentation, flocculation, and precipitation are available for the elimination of toxic pollutants from wastewater, issues such as their cost and efficacy limit their usage. Recently, catalysis has been found to be the most effective approach since it exhibits significant capability to eliminate almost all the pollutants and offers the benefit of simple design and low initial cost. In the present study, ternary zinc–copper–nickel layered double hydroxide (ZnCuNi‐LDH) synthesized using facile acid hydrolysis method was employed as an efficacious heterogeneous catalyst for the reduction of NACs (para‐nitrophenol and para‐nitroaniline) and degradation of organic azo dyes (methyl orange, amaranth, and brilliant black). ZnCuNi‐LDH exhibited superior catalytic activity for the reduction of all five model pollutants with reduction efficiency of more than 95% within a short time span of 5 min. Therefore, keeping in view the layered structure, high specific surface area, and remarkable catalytic performance, ZnCuNi‐LDH holds immense potential for the large‐scale catalytic degradation of refractory pollutants.

Removal of Cr(VI) from Wastewater Using Acrylonitrile Grafted Cellulose Extracted from Sugarcane Bagasse

A highly efficient low-cost adsorbent was prepared using raw and chemically modified cellulose isolated from sugarcane bagasse for decontamination of Cr(VI) from wastewater. First, cellulose pulp was isolated from sugarcane bagasse by subjecting it to acid hydrolysis, alkaline hydrolysis and bleaching with sodium chlorate (NaClO3). Then, the bleached cellulose pulp was chemically modified with acrylonitrile monomer in the presence Fenton’s reagent (Fe+2/H2O2) to carry out grafting of acrylonitrile onto cellulose by atom transfer radical polymerization. The developed adsorbent (acrylonitrile grafted cellulose) was analyzed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Both raw cellulose and acrylonitrile grafted cellulose were used for chromium removal from wastewater. The effects of metal ion concentration, pH, adsorbent dose and time were studied, and their values were optimized. The optimum conditions for the adsorption of Cr(VI) onto raw and chemically modified cellulose were: metal ion concentration: 50 ppm, adsorbent dose: 1 g, pH: 6, and time: 60 min. The maximum efficiencies of 73% and 94% and adsorption capacities of 125.95 mg/g and 267.93 mg/g were achieved for raw and acrylonitrile grafted cellulose, respectively. High removal efficiency was achieved, owing to high surface area of 79.92 m2/g and functional active binding cites on grafted cellulose. Isotherm and kinetics studies show that the experimental data were fully fitted by the Freundlich isotherm model and pseudo first-order model. The adsorbent (acrylonitrile grafted cellulose) was regenerated using three different types of regenerating reagents and reused thirty times, and there was negligible decrease (19%) in removal efficiency after using it for 30 times. Hence, it is anticipated that acrylonitrile could be utilized as potential candidate material for commercial scale Cr(VI) removal from wastewater.

Production and Characterization of Nanocellulose from Maguey (Agave cantala) Fiber

Plant fibers have been studied as sources of nanocellulose due to their sustainable features. This study investigated the effects of acid hydrolysis parameters, reaction temperature, and acid concentration on nanocellulose yield from maguey (Agave cantala) fiber. Nanocellulose was produced from the fibers via the removal of non-cellulosic components through alkali treatment and bleaching, followed by strong acid hydrolysis for 45 min using sulfuric acid (H2SO4). The temperature during acid hydrolysis was 30, 40, 50, and 60 °C, and the H2SO4 concentration was 40, 50, and 60 wt. % H2SO4. Results showed that 53.56% of raw maguey fibers were isolated as cellulose, that is, 89.45% was α-cellulose. The highest nanocellulose yield of 81.58 ± 0.36% was achieved from acid hydrolysis at 50 °C using 50 wt. % H2SO4, producing nanocellulose measuring 8–75 nm in diameter and 72–866 nm in length, as confirmed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Fourier-transform infrared spectroscopy (FTIR) analysis indicated the chemical transformation of fibers throughout the nanocellulose production process. The zeta potential analysis showed that the nanocellulose had excellent colloidal stability with a highly negative surface charge of −37.3 mV. Meanwhile, X-ray diffraction (XRD) analysis validated the crystallinity of nanocellulose with a crystallinity index of 74.80%. Lastly, thermogravimetric analysis (TGA) demonstrated that the inflection point attributed to the cellulose degradation of the produced nanocellulose is 311.41 °C.

DEVELOPMENT OF MYCROCRYSTALLINE CELLULOSE ORIGINATE FROM SAGO (METROXYLON SAGU) STEM BARK BY HYDROLISIS METHODE USING NITRIC ACID

Objective: Microcrystalline cellulose (MCC) is an essential excipient in tablet formulation. Mostly MCC was obtained from wooden conifer stem fiber, therefore environment issues had been came up. Alternative sources for MCC which offer friendly conifer wood need to be explored. This study aimed to isolate and determine the characteristics of MCC originated from Sago (Metroxylon sago Rottb.) stem fibers as an promising alternative of MCC. Methods: MCC was prepared through pre-hydrolysis using an acetic acid solution, alkali heating using NaOH solution, and acid hydrolysis using nitric acid 0.3 N using three variations of heating temperature, namely 90, 95 and 100 °C. The characterization carried out were pharmaceutical grade, powder properties, FTIR analysis and powder morphology by SEM. Results: The yields obtained were 66.02; 65.53 and 65.08%, respectively. The characteristics of the MCC sample based on pharmaceutical grade quality were white to yellowish white powder, odorless, tasteless, insoluble in: ether, 96% alcohol, HCl 2N and NaOH 1N. The pH of the MCC suspension were 5.07-5.12, while moisture content were 3.67-4.17%, with loss on drying value as much as 0.37-0.4%, and ash content 1-2.17%. The value of permanganate number were 0.09-0.11, Hausner factor was between 1.05-1.25, and angle of repose were between 11.4-24.8°. Conclusion: Based on the results, it can be concluded that Sago is potent natural resource for MCC. The resulting MCC revealed physicochemical and characteristic of MCC, which almost similar to Avicel PH 102 as standard.

DIVERSITY AND PHYTATE-DEGRADING POTENTIAL OF YEAST MICROORGANISMS ISOLATED FROM SOURDOUGH

Phytases, which perform the stepwise hydrolysis of phytic acid to myo-inositol and inorganic phosphate, are used worldwide to reduce phosphorus pollution and improve nutrition in monogastric animals and humans. Yeasts isolated from their natural environments represent rich and still underexplored sources of industrially valuable enzymes, including phytases; therefore, they are widely studied for the production of these enzymes. In this regard, thirteen yeast pure cultures were isolated from the microbial consortium of four types of sourdough obtained during the natural fermentation of different grain-based flours. Ten of the newly isolated yeast strains were selected as potential phytase producers based on their growth in liquid culture media with sodium phytate as the sole source of phosphorus. Using 18S rDNA and D1/D2 26S rDNA analyses, the species affiliation of the selected isolates was established. They referred to seven yeast species from 3 families, with the most significant representation of the family Saccharomycetaceae.Intracellular phytate-degrading activity was found in 8 isolates, the highest being in Nakaseomyces glabratus strain 7-4. The highest level of extracellular phytase was measured in Pichia membranifaciens strain 5-2. Both isolates showed significant antioxidant capacity higher than those of ascorbic acid.

DEGRADATION ESTIMATION OF ROSUVASTATIN CALCIUM IN PHARMACEUTICAL TABLET FORMULATION

Objectives: The present objective was to undertaken the Rosuvastatin Calcium degradation in the tablets formulations with a rapid, economic, consistent, specific and simple analytical procedure. Methods: The analytical RP-HPLC was validated with mobile phase composition of methyl alcohol : cyanomethane : water (45:35:20,v/v). The detection was achieved with a flow 1.0 ml/min by using octylsilane column (250 x 4.6 mm, 5 µ), at 248 nm. Results: The established analytical procedure of Rosuvastatin Calcium was validated statistically for reproducibility, accuracy, specificity as per ICH-guideline. The correlation coefficient was 0.999 with the linearity concentration range 140-260 µg/ml. The percentage recovery was achieved 99.86 to 106.12 and RSD% of precision was 0.599. The specificity was confirmed by excellent photolytic and thermal stability of Rosuvastatin Calcium. The degradation statistical recovery of Rosuvastatin Calcium in dry, wet and thermal stage ware 99.25%, 99.52 % and 99.64% respectively validated. The developed peaks in the chromatograms of alkali, oxidation and acid decomposition of Rosuvastatin Calcium were confirmed by screening the degradation peaks and the recovery percentage were found 23.16 %, 85.59 % and 66.33 % respectively. Conclusions: The stress conditions of Rosuvastatin Calcium in degradation study is successfully developed and it is also important in stability to determined the highest lipid lowering agent in the body that block the manufacturing of cholesterol. The stress conditions like in aqueous acidic hydrolysis, oxidative, alkaline hydrolysis, thermal and photolytic degradation study was validated with a simple, cost efficient, linear, accurate, selective, specific, high performance liquid chromatography with a simple effortless mobile phase containing methyl alcohol, cyanomethane and water.

Green banana resistant starch: A promising potential as functional ingredient against certain maladies

AbstractThis review covers the significance of green banana resistant starch (RS), a substantial polysaccharide. The food industry has taken an interest in green banana flour due to its 30% availability of resistant starch and its approximately 70% starch content on a dry basis, making its use suitable for food formulations where starch serves as the base. A variety of processing techniques, such as heat‐moisture, autoclaving, microwaving, high hydrostatic pressure, extrusion, ultrasound, acid hydrolysis, and enzymatic debranching treatments, have made significant advancements in the preparation of resistant starch. These advancements aim to change the structure, techno‐functionality, and subsequently the physiological functions of the resistant starch. Green bananas make up the highest RS as compared to other foods and cereals. Many food processing industries and cuisines now have a positive awareness due to the functional characteristics of green bananas, such as their pasting, thermal, gelatinization, foaming, and textural characteristics. It is also found useful for controlling the rates of cancer, obesity, and diabetic disorders. Moreover, the use of GBRS as prebiotics and probiotics might be significantly proved good for gut health. This study aimed at the awareness of the composition, extraction and application of the green banana resistant starch in the future food products.

Enhancing the dilute acid hydrolysis process using a machine learning approach: investigation of different biomass feedstocks influences glucose and ethanol yields

Enhancing the dilute acid hydrolysis process using a machine learning approach: investigation of different biomass feedstocks influences glucose and ethanol yields

Acid-hydrolyzed phenolic extract of parsley (Petroselinum crispum L.) leaves inhibits lipid oxidation in soybean oil-in-water emulsions

The antioxidant activity of the natural phenolic extracts is limited in particular food systems due to the existence of phenolic compounds in glycoside form. Acid hydrolysis post-treatment could be a tool to convert the glycosidic polyphenols in the extracts to aglycones. Therefore, this research investigated the effects of an acid hydrolysis post-treatment on the composition and antioxidant activity of parsley extracts obtained by an ultrasound-assisted extraction method to delay lipid oxidation in a real food system (i.e., soybean oil-in-water emulsion). Acid hydrolysis conditions were varied to maximize total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. When extracts were exposed to 0.6 M HCl for 2 h at 80 ℃, TPC was 716.92 ± 24.43 µmol gallic acid equivalent (GAE)/L, and DPPH radical scavenging activity was 66.89 ± 1.63 %. Not only did acid hydrolysis increase the concentrations of individual polyphenols, but it also resulted in the release of new phenolics such as myricetin and gallic acid. The extract's metal chelating and ferric-reducing activity increased significantly after acid hydrolysis. In soybean oil-in-water emulsion containing a TPC of 400 µmol GAE/L, the acid-hydrolyzed extract had an 11-day lag phase for headspace hexanal compared to the 6-day lag phase of unhydrolyzed extract. The findings indicated that the conversion of glycosidic polyphenols to aglycones in phenolic extracts can help extend the shelf-life of emulsion-based foods.

Validated chromatographic methods for determination of teriflunomide and investigation of its intrinsic stability

Two rapid, precise, and sensitive stability-indicating high performance chromatographic methods for the measurement of Teriflunomide in its degradation products’ existence were developed. These were RP-HPLC and HPTLC using UV detector. HPLC separation was accomplished utilizing Thermo BDS hypercil C18 column (250 × 4.6 mm, 5 μm) and acetonitrile: 0.03 M potassium dihydrogen phosphate: triethylamine (50:50:0.1%, by volume) as mobile phase at flow rate of 1mL/min. The separated peaks were detected at 250.0 nm. The densitometric approach was conducted utilizing HPTLC 60 F254 silica gel plates, and a developing system of benzene: ethanol: acetic acid (7.5:1:0.25, by volume) and detection was done at 250.0 nm. The developed approaches were evaluated regarding the International Conference on Harmonization (ICH) instructions. The calibration curves of both techniques were constructed with linearity ranges of (5-100) µg/mL and (2–10) µg /band, for HPLC and densitometric determination, consecutively. Teriflunomide was exposed to base and acid hydrolysis, oxidation using H2O2 and finally, thermal degradation as stated in ICH guidelines. The degradation product structures’ elucidation was achieved through LC-MS.

Identification and characterization of organic and glycosidic acids in the crude resin glycoside fraction of Ipomoea alba seeds

Resin glycosides act as laxatives in crude drugs derived from plants of the Convolvulaceae family. These compounds have exhibited antibacterial, ionophoric, anti-inflammatory, antiviral, and multidrug resistance-modulating properties, as well as cytotoxicity against cancer cells. This study investigated the organic acid, hydroxyl fatty acid, monosaccharide, and glycosidic acid components of the crude resin glycoside fraction obtained from the methanol extract of Ipomoea alba L. (Convolvulaceae) seeds, which was subjected to alkaline and acidic hydrolysis. The alkaline hydrolysis yielded acetic, isobutyric, (E)-2-methylbut-2-enoic, and 2S-methyl-3S-hydroxybutyric acids as organic acid components, along with a glycosidic acid fraction. The acidic hydrolysis of the glycosidic acid fraction resulted in the isolation of 11S-hydroxytetradecanoic and 11S-hydroxyhexadecanoic acids as hydroxyl fatty acid components, as well as d-glucose, d-quinovose, d-fucose, d-xylose, and l-rhamnose as monosaccharide components. In addition, 10 new glycosidic acid methyl esters were isolated from the glycosidic acid fraction treated with trimethylsilyldiazomethane–hexane, along with one known glycosidic acid methyl ester. Of these, eight compounds contained new glycans. Four of these compounds were unusual natural glycosides with four glycosidic linkages to one monosaccharide. Their structures were determined using MS and NMR spectral analyses, which provided valuable insights into the unique glycosidic composition of I. alba seeds.

Evaluation of the polycaprolactone hydrolytic degradation in acid solvent and its influence on the electrospinning process

AbstractPolycaprolactone (PCL) is a pivotal biopolymer in biomedicine, especially in tissue engineering for scaffolds and biomaterials. Recognized for its effectiveness as a drug carrier with superior controlled release properties, PCL is commonly processed via electrospinning, typically employing chlorinated or fluorinated solvents known for cellular toxicity. As an environmentally conscious alternative, this study explores glacial acetic acid (AA) as a solvent for electrospinning solutions. Investigating PCL's molecular degradation through acid hydrolysis in acidic solvents (AA/formic acid) (FA), the study assesses the impact of storage time on resulting structures. Solutions containing 30% PCL in AA/FA (9:1) were stored at 35°C for up to 14 days, revealing a 50% molar mass reduction during solubilization through gel permeation chromatography, x‐ray diffraction, and Fourier‐transform infrared analyses. This reduction influenced chain packing, raising crystallinity indices from approximately 37% to 49% with prolonged storage. The reduced molar mass resulted in unstable Taylor cones, generating diverse mat morphologies. Intriguingly, this degradation enhanced water adsorption capacity, indicating exposed hydrogen bonds from acid hydrolysis as an advantageous trait for regenerative medicine. This underscores the hydrolyzed materials' potential for cell anchoring in tissue engineering.

Characterization and Performance Analysis of Hydrolyzed versus Non-Hydrolyzed Poly(NVF-co-HEA) Hydrogels for Cosmetic Applications

This study explores the synthesis and modification of poly(N-vinylformamide-co-N-hydroxyethyl acrylamide) (poly(NVF-co-HEA)) hydrogels for cosmetic applications. Poly(NVF-co-HEA) hydrogels were produced followed by an acid hydrolysis reaction to produce poly(NVF-co-VAm-co-HEA) hydrogels, introducing poly(vinyl amine) (PVAm) into the structure. This modification considerably alters the hydrogels’ properties, yielding materials with over 96% water content, predominantly in the form of non-freezing or free water, which is beneficial in the uptake and release of hydrophilic species. The primary amine groups from inclusion of VAm also improved the mechanical properties, as evidenced by an 8-fold increase in Young’s modulus. The hydrogels also possessed pH-responsive behavior, which was particularly noticeable under acidic and basic conditions, where a large decrease in water content was observed (40% to 75% reduction). Characterizing the hydrogels’ release capabilities involved using organic dyes of different functional groups and sizes to examine the pH impact on release. The results indicated that hydrolyzed hydrogels interacted more effectively with charged species, highlighting their suitability for pH-responsive delivery. The release of cosmetic active ingredients was also demonstrated through the controlled release of Liquid Azelaic™, specifically potassium azeloyl diglycinate (PAD). Our findings reveal that the hydrolyzed hydrogels exhibit superior burst release, especially under alkaline conditions, suggesting their suitability for cosmetic applications where controlled, pH-responsive delivery of active ingredients is desired. Overall, this investigation highlights the potential of hydrolyzed poly(NVF-co-HEA) hydrogels in cosmetic applications. Their ability to combine high water content with mechanical integrity, along with their pH-responsive release ability, allows for use in cosmetic formulations.

Bioethanol from Arthrospira platensis Biomass using a Combined Pretreatment

With the aim to reduce the reliance on gasoline by supporting efficient bioethanol production to meet the biofuel goal of 46% in the transportation sector by 2050, the present study proposes a combined pretreatment of microwave-assisted acid hydrolysis for bioethanol production, which was applied to commercially-produced microalgal biomass of Arthrospira platensis. The Separated Hydrolysis and Fermentation (SHF) method was applied to prevent sugar loss and produce a higher bioethanol yield. After examining the effect of acid concentrations (0, 0.1, 0.2, and 0.3 M) and hydrolysis duration (30, 60, 90, 120, and 180 minutes) on the fermentable sugars, it was discovered that both operation parameters had a major impact on the synthesis of monosaccharides. With a 0.3 M H2SO4 concentration and a 90-minute hydrolysis time at 100°C, the maximum concentration of fermentable sugars of 11.60 g/L was obtained. Regarding the fermentable sugar yield, the suggested combined pretreatment (78.4%) outperforms the literature-reported single pretreatment of acid hydrolysis (55%), under comparable operating settings. After 96 hours of anaerobic fermentation with Saccharomyces cerevisiae, the hydrolysate of the fermentable sugars produced 0.06 g ethanol/g biomass, corresponding to 0.35 g ethanol/g total carbohydrates in Arthrospira platensis.