Acid Hydrolysis Method Research Articles

Screening and Selection of a New Medium and Culture Conditions for Diosgenin Production via Microbial Biocatalysis of SYt1

Diosgenin (DSG) is a phytosterol saponin mainly found in Dioscorea zingiberensis C.H. Wright. It has shown promising results in treating various diseases such as cancer, diabetes, arthritis, asthma, and cardiovascular diseases. Diosgenin is also an important medicinal chemical for synthesizing various steroid medicines. The production of diosgenin by acid hydrolysis generates a large amount of wastewater, leading to severe environmental pollution. However, producing diosgenin through microbial fermentation can effectively reduce environmental pollution. Numerous studies have demonstrated that various microorganisms can produce diosgenin via solid-state fermentation. Nevertheless, due to the complexity, high maintenance costs, uneven heat production, and other characteristics of solid-state fermentation, it is not commonly used in the industrial production of diosgenin. In contrast, liquid fermentation offers advantages such as simple operation, easy maintenance, and stable fermentation, making it more suitable for the industrial production of diosgenin. However, few studies have focused on producing diosgenin using liquid fermentation. In this study, endophytic Bacillus licheniformis SYt1 was used to produce diosgenin via liquid fermentation, with Dioscorea tuber powder as a substrate. Soxhlet extraction and silica gel column chromatography were employed to identify the diosgenin from the liquid fermentation products. Suitable fermentation conditions were screened and identified. The environmental variables that significantly affect the diosgenin yield were determined by the Plackett–Burman design (P-BD) with eight factors. The three factors (peptone, yeast extract powder and inorganic salt) with the greatest influence on the diosgenin yield were selected and further optimized using a response surface methodology (RSM). The final culture conditions were determined to be 35.79 g/L of peptone, 14.56 g/L of yeast extract powder, and 1.44 g/L of inorganic salt. The yield of diosgenin under these conditions was 132.57 mg/L, which was 1.8 times greater than the yield under pre-optimization conditions. This effective, clean, and promising liquid fermentation method possesses the potential to replace the traditional acid hydrolysis method for the industrial production of diosgenin.

New Insights into the Antibacterial Activity of Hydroxytyrosol Extracted from Olive Leaves: Molecular Docking Simulations of its Antibacterial Mechanisms.

This study investigated the biological activities of a hydroxytyrosol-rich extract from Olea europaea leaves, particularly its ability to eradicate severe pathogenic bacteria producing Extended-Spectrum Beta-Lactamases (ESBLs). The latter bacteria are emerging microorganisms that pose significant challenges due to their resistance to a broad range of potent therapeutic drugs. The extract was prepared through an accessible acid hydrolysis method. In vitro and In silico analyses through MIC, MBC analysis and molecular docking were conducted to evaluate the antibacterial properties. The extract showed remarkable antioxidant activity and significant antibacterial potential against reference species and ESBL bacteria. MIC and MBC calculations confirmed the extract's capacity to kill bacteria rather than just inhibit their growth. Further in silico analyzes demonstrated the high binding affinity of HT to the active sites of the gyrase B subunit and the peptidoglycan DD-transpeptidase domain from proteins located in the cytoplasm and the cell wall of the bacteria, respectively. Results confirmed the structure-activity relationship and the ability of HT to disrupt essential bacterial functions. This study validates the debated antimicrobial potential of HT and highlights its importance as a potential therapeutic agent against resistant bacteria, which is a critical area of research given the global challenge of antibiotic resistance.

Rapid and efficient high-performance liquid chromatography-ultraviolet determination of total amino acids in protein isolates by ultrasound-assisted acid hydrolysis

This study presents the optimization and validation of an ultrasound-assisted acid method for the HPLC-UV determination of amino acids in plant-based proteins. The research focuses on enhancing hydrolysis efficiency and reducing environmental impact. Ultrasound treatment significantly accelerated hydrolysis by creating cavitation, which increases local pressure and temperature, leading to faster reaction rates. The optimal condition was a 30-minute treatment at 90 °C with 6 M hydrochloric acid. The 9-fluorenylmethyloxycarbonyl chloride derivatization was best performed at pH 9.0 using borate buffer, ethanol as the organic solvent, and a 5-minute derivatization time with a 5 mM concentration. The method’s analytical performance, validated according to FDA guidelines, showed excellent selectivity, specificity, linearity (r2 > 0.999), accuracy (recovery between 80–118 %), and precision (RSD<10.9). The analysis of 15 plant-based proteins revealed distinct amino acid profiles. Compared to traditional acid hydrolysis methods, the ultrasound-assisted approach demonstrated no significant difference in results (p-value > 0.05), confirming its reliability. The optimized ultrasound-assisted method is a reliable and efficient alternative for amino acid analysis, offering significant cost and time savings while maintaining high analytical performance. These findings are crucial for nutritional planning and developing functional foods to improve health outcomes.

Correlation between preparation techniques and frictional properties of cellulose nanocrystals as additives in water-based lubricants

To explore the tribological characteristics of cellulose nanocrystals derived through various preparation techniques when utilized as additives in water-based lubricants, two types of cellulose nanocrystals (S-CNC and C-CNC) were chosen. These were produced via sulfuric acid hydrolysis and oxidation methods. The morphology and structural features were assessed through techniques such as Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), laser confocal Raman spectroscopy, elemental analysis, scanning electron microscopy (SEM), and laser particle size analysis. According to thermogravimetric analysis (TGA), the thermal stability of S-CNC is slightly superior to that of C-CNC. S-CNC exhibits liquid crystallinity when the concentration exceeds 0.5 %, whereas C-CNC does not display liquid crystallinity at any concentration tested. Further investigation was conducted on the frictional properties of the two types of CNCs using a UMT reciprocating friction tester. The results indicate that both types of CNC exhibit significant friction reduction properties at various additive concentrations, provided the addition does not exceed w=1 %. When below their respective liquid crystalline phase concentrations, the friction reduction performance of S-CNC is slightly inferior to that of C-CNC; however, when above the liquid crystalline phase concentration, the friction reduction performance of S-CNC surpasses that of C-CNC. The addition of w=0.5 % S-CNC leads to a relative reduction of 63.4 % in the friction coefficient compared to the base system. Analysis of the steel plate surface contact angle and post-wear surface suggests that the lubrication mechanism of CNC involves the adsorption of polar functional groups such as hydroxyl or carboxyl groups from the CNC structure onto the friction pair surface, forming a lubricating protective film to varying degrees. Additionally, the liquid crystalline structure of S-CNC facilitates the formation of an ordered lubricating film, further enhancing the frictional properties. These findings provide valuable insights into the application of nanocellulose crystals as lubricant additives.

Properties of hydrogel for adsorbent textile dye waste based cellulose-carboxymethyl sago starch

Abstract The use of a single natural polymer in hydrogel preparations is considered insufficient to produce hydrogels that are more durable, more stable, and stronger. Blends of various natural polymers can improve each sago other’s lack of physicochemical characteristics and produce new properties. This research combines two natural polymers, cellulose and starch. Cellulose isolation from Gracilaria verrucosa seaweed using acid hydrolysis and alkaline autoclaving method produced 14.01% cellulose. This study combined the results of cellulose isolation with carboxymethyl sago starch at 0.09; 0.14 and 0.24 mol/mol AGU. The isolated cellulose-carboxymethyl sago starch has the potential as a hydrogel material with the addition of crosslinkers such as epichlorohydrin (ECH). This study aims to synthesize hydrogels from cellulose-carboxymethyl sago starch with application as a textile dye waste absorbent with a concentration of epichlorohydrin (ECH) at 7.5%. Analysis of carboxymethyl sago starch is degrees of substitution, water-soluble index (WSI), and swelling power (SP). The hydrogel properties are characterized by the degree of swelling, degree of polymerization, FTIR, and SEM, and the hydrogel adsorption ability is characterized by adsorption efficiency using a microplate reader. The research results show that hydrogel can be synthesized optimally by adding carboxymethyl sago starch (CMSS) at 0.24 mol/mol AGU. The results of FTIR analysis are also by chemical measurements (swelling and gel fraction). In contrast, for maximum colour absorption, the addition of carboxymethyl sago starch is 0.09 mol/mol AGU for purple, yellow, and black and 0.14 mol/mol AGU for green color absorption. In conclusion, the adsorption ability of hydrogel in commercial textile dyes is maximum when the carboxymethyl sago starch (CMSS) is added at 0.09 mol/mol AGU with the best adsorption efficiency at purple 86.22%, yellow 77.40%, black 73.70% and at the addition of CMSS 0.14 mol/mol AGU the best adsorption efficiency in green is 73.46%.

Glucose Syrup from Purple Sweet Potatoes (Ipomoea batatas L. Poir) using Acid Hydrolysis Method

&lt;p&gt;&lt;strong&gt;Abstract.&lt;/strong&gt; The making of glucose syrup from purple sweet potatoes is motivated by the high demand for alternative sugar in Indonesia. Through the processes that have been carried out and the results of previous studies, the potential of purple sweet potatoes to be processed into glucose syrup has been produced. This experiment was conducted to determine whether purple sweet potatoes can be processed into glucose syrup and to determine the suitability of the product to the standard. To convert purple sweet potatoes into glucose syrup, it is necessary to first extract the starch content in purple sweet potatoes and go through the process of making glucose syrup by the acid hydrolysis method using citric acid of various concentrations (0.2, 0.4, 0.6, 1 N). For the feasibility of consuming glucose syrup from purple sweet potatoes, a toxicity test was carried out using the Brine Shrimp Lethality Test (BSLT) method. Tests were also carried out on water, ash, reducing sugar, and starch content to then be compared with the Indonesian glucose syrup standard (SNI 01-2978-1992). The results showed that the reducing sugar content of purple sweet potato glucose syrup followed the glucose syrup quality standard, which was 43.31%, the lowest water content was 18.35%, the lowest ash content was 7.95% and there was no starch content in purple sweet potato liquid sugar. The aroma of the glucose syrup produced was following the Indonesian National Standard, but the color and taste produced were not yet in accordance. The toxicity test of purple sweet potato liquid sugar showed a lethal concentration value of LC&lt;sub&gt;50&lt;/sub&gt; &amp;gt;1,000 ppm, which means that purple sweet potato liquid sugar has no toxic potential so it is safe for consumption.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords:&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Purple Sweet Potatoes, Liquid Sugar, Acid Hydrolysis&lt;/p&gt;&lt;p&gt;&lt;strong&gt;&lt;br /&gt;&lt;/strong&gt;&lt;/p&gt;

Nanocellulose-Based Resistive Sensors for Air Humidity Measurements

Introduction. The measurement of relative air humidity plays a crucial role in various aspects of human life, such as climate control systems, medical breath and skin hydration monitoring. Typically, humidity sensors use inorganic materials and petroleum-derived polymers. However, there is a growing trend towards the transition to biodegradable materials, which eliminates the need for waste disposal.Problem Statement. Currently, nanocellulose (NC) has been being explored as a promising material for humidity sensors. However, the influence of the chemical composition and nanoparticle size of NC on the sensor characteristics remains understudied.Purpose. This study aims to investigate the influence of the chemical composition and structure of NC on the parameters of humidity sensors.Materials and Methods. NC has been synthesized from reed stalks and wheat straw bz the oxidation and acid hydrolysis methods. NC-film sensors having a mass within 0.3—3 mg have been fabricated. The static parameters (response, sensitivity, reversibility, and repeatability) and the dynamic parameters (short and long-term stability, response and recovery time) of the sensors have been analyzed.Results. The manufacturing method influences the NC chemical composition, while the origin material affects its structure. The sensors produced by the oxidation method have demonstrated improved sensitivity (2.69 · 106), response (0.2 (%RH)–1), recovery time (60 s) and long-term stability (1.44%) as compared with those made by the hydrolysis method. Additionally, the application of wheat straw NC as origin material has resulted in improved reversibility (5%), repeatability (5% deviation), short-term stability (30% deviation), and response time (1 s) as compared with the reed stalks NC.Conclusions. It has been established that the origin material of nanocellulose influences the reversibility, repeatability, response time, and short-term stability of the sensors. The manufacturing method has effect on the sensitivity, response, recovery time, and long-term stability of the sensors.

Green preparation of cellulose nanocrystals and nanofibers by ball milling assisted citric acid hydrolysis

In order to solve the drawbacks of carboxylated cellulose nanocrystals (CNCs) prepared by critic acid (CA) hydrolysis method, such as low yield and low esterification degree, herein, ball milling assisted CA hydrolysis method was applied to obtain carboxylated CNCs and cellulose nanofibers (CNFs) with fine and uniform size, high yield and carboxyl content, good crystallinity, and good thermal stability. It was discovered that the diameter of CNCs and CNFs were decreased and the size uniformity was improved. The yield of CNCs was obviously improved to 39.8 % due to the promoted esterification reaction, which was 3.3 times of that without ball milling. Moreover, the carboxyl group content of CNCs and CNFs were improved to a maximum of 0.52 and 0.48 mmol/g, respectively. As ball milling progressing, more amorphous regions were destroyed and cellulose bundles were dissociated, resulting in CNCs and CNFs with high crystallinity. The thermal decomposition temperature of CNCs and CNFs were ranged from 317 to 331℃, which was higher than that had reported. This work provided an effective route for carboxylated CNCs with good yield, esterification degree and other performance, which was beneficial for the subsequent applications in the field of biomaterials.

COMPARISON OF RESULTS OF PULUT CORN STARCH MODIFICATION AND SORGUM STARCH BY ACID HYDROLYSIS METHOD

Starch is a carbohydrate which is a glucose polymer, and consists of amylose and amylopectin, for example corn and sorghum starch, but it still has several obstacles when used as raw materials in the food and non-food industries. If starch is cooked it takes a long time (requiring high energy), and the paste that is formed is hard and not clear. Therefore, starch modification was carried out by acid hydrolysis. This research was conducted to evaluate the effect of physical modification on pulut corn starch and sorghum starch using the Acid Hydrolysis method. The research was conducted at the Processing Laboratory, Department of Food Science and Technology, Faculty of Agriculture, Gorontalo State University in May 2024. The tools used were containers, glass beakers, ovens, water baths, blenders, sieves, plastic clips. The ingredients used are pulut corn flour, sorghum flour, distilled water, NaOH, and citric acid. The research design used a Completely Randomized Design (CRD). Test parameters include the size of starch granules. It is hoped that the research results will provide new insights in the development of starch technology based on corn and sorghum.

Characteristics of Cellulose Nanofibrils From Arabica Coffee Skin Prepared by the Acid Hydrolysis

Cellulosenanofibrils (CNF) is a new generation material that has high performance, good physics and medical properties and is a renewable material that has been developed from various sources using the acid hydrolysis method. CNF synthesis is generally obtained from logs that have a high amount of cellulose fiber. Cellulose nanofibrils (CNF) from arabica coffee skins have great potential to be developed as raw materials for medicines, which function as wound healing agents, surgical sutures, diet medicines, and skin softeners. CNF is produced from Arabica coffee skin through delignification, namely the removal of lignin and hemicellulose by extraction with alkali until α-cellulose is obtained, then CNF is synthesized through hydrolysis using dilute acid. From the coffee skin extraction results, a high cellulose yield was obtained, reaching above 24.30% and crystallinity reaching 79.60%. Hydrolysis by 10%, 12% and 15% HCl with a reaction time of 2 hours, the respective crystallinity was 80.66; 79.06; and 77.69%.

Bioactive enhancement of PVA films through CNC reinforcement and Ficus auriculata fruit extract: A novel synthesis for sustainable applications

Cellulose nanocrystals (CNCs) have received immense interest lately as a potential nanomaterial because of their excellent mechanical and biological properties. This investigation aims to formulate a composite coating made of polyvinyl alcohol (PVA), CNCs, and a methanolic extract from the dried leaves and fruit of the fig tree (Ficus auriculata) (FAE). A sequential procedure to get CNCs included alkaline and acid hydrolysis, sonication, and suitable methods for purification. Analytical techniques like X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were used to study the CNC-loaded films. Thermogravimetric analysis (TGA) of composites revealed superior thermal stability of the CNC-reinforced films versus control, evident from higher degradation temperatures, indicating desirable environmental resistance of proposed coatings for wood surfaces. The termite control was made more effective through synergistic use of a combination of CNCs, PVA, and FAE with proven insecticidal properties. The composite material was examined for its anti-termite resistance and termite mortality rate, and demonstrated that when used together, CNCs, PVA, and FAE were collectively and synergistically more effective at keeping termites away. The findings of this study demonstrate that the evolved composite could be used to develop anti-termite products that are environmentally benign and respond well. Synthesized composites also demonstrated significant antibacterial activity. Among all films, a combination of 0.7 % extract in PVA displayed excellent results with 26 and 28 mm diameter for growth inhibition zone for Gram-positive bacteria whereas 26 mm for both negative bacterial strains. The findings suggest a potential use of this composite as a sustainable, environmentally resistant, and eco-friendly alternative for termite/bacterial control in various building materials and wood preservation applications.

Obtaining cellulose nanocrystals by acid hydrolysis procedure; and their use as reinforcement in polylactide biocomposites

In the first step of this study, purpose was to obtain and characterize cellulose nanocrystal (CNC) particles by applying sulfuric acid hydrolysis method to the starting material of microcrystalline cellulose (MCC) fibrils. After obtaining CNC particles via acid hydrolysis procedure, various analyses (SEM, DLS, FTIR, XRD, TGA) conducted revealed that average size of round shaped CNC particles was 38 nm with −30.4 mV Zeta potential value. They had monoclinic Cellulose-I crystal structure with Crystallinity Index of 80.6% and Crystallite Size of 3.39 nm. Their maximum thermal degradation temperature was 307°C with 23 wt% residue at 800°C. In the second step, the main aim was to investigate contribution of these obtained CNC particles when they were used as nano-reinforcement in polylactide (PLA) matrix biocomposites produced by industrially compatible melt mixing and shaping techniques. Mechanical tests revealed that when only 1 wt% CNC particles were incorporated into PLA matrix, increases in flexural strength and modulus were 29% and 51%; while increases in K IC and G IC fracture toughness values were 42% and 105%, respectively. Because, high degree of hydroxyl groups and presence of sulfate half-ester groups on the surfaces of CNC particles improved the interfacial interactions between the matrix and nano-reinforcement phase, leading to efficiency in strengthening and toughening mechanisms.

Two-response surface design optimization of carboxylated CNCs with super high thermal stability and dye removal capability

Discharging wastewater from industrial dyeing and printing processes poses a significant environmental threat, necessitating green and efficient adsorbents. Cellulose nanocrystals (CNCs) have emerged as a promising option for dye adsorbing. However, the industrial production and commercialization of CNCs still faced low yield, time-consuming, and uneco-friendly. In this study, we proposed a facile hydrochloric/maleic acid (HCl/C4H4O4) hydrolysis method to synthesize carboxylated CNCs using Box-Behnken design and dual response surface design, which can systematically investigate the effect of experimental factors (temperature, time and HCl/C4H4O volume ratio) on the final products. The rod-liked carboxylated CNCs gave the highest yield of 90.50 %, maximum carboxyl content of 1.29 mmol/g, and efficient dye removal ratio of 91.5 %. Furthermore, compared to CNCs obtained by commonly sulfuric acid hydrolysis way (CNCs-S) with a Tmax of 242.6 °C, the CNCs extracted at 5 h exhibited significantly improved thermal stability with Tmax reaching 351.2 °C. The enriched carboxyl content and excellent thermal stability show potential wastewater treatment applications under harsh conditions.

Amino Acids Isolation from α-keratin of Javanese Goat (Capra hircus) Hair and Garut Sheep (Ovis aries) Hair Waste Using Acid Hydrolysis Method as BCAA Supplement

Javanese goat and Garut sheep hair contain α-keratin, a protein that can be broken by hydrolysis to produce simpler amino acids. Feather waste generates millions of tons of α-keratin biomass originating from animal slaughterhouses, thereby raising health concerns. The utilization of acid hydrolysis is considered to be more cost-effective compared to enzymatic hydrolysis, and it provides a broader range of amino acid cleavage sites compared to enzymes, which exhibit specific cleavage. This study aimed to isolate amino acids from Javanese goat and Garut sheep hair through acid hydrolysis. The methods included hair sample preparation, acid hydrolysis used 6 M HCL at 110°C, reflux isolation, amino acid separation based on isoelectric pH 4.9 –5.4, functional groups analysis using FTIR, and analysis of amino acid content by HPLC methods. The results showed that the yield produced after isolation on Javanese goat hair samples was 0.92% and Garut sheep hair 0.32%, respectively. The FTIR spectrum showed amino acid functional groups in both samples, including carboxyl (COOH), amine (C-N primer), (C-S disulfide), and amide I (-CONH2). Successful breakdown of α-keratin proteins into simpler amino acids was achieved for Javanese goat and Garut sheep hair. Amino acid analysis of Javanese goat hair isolates revealed the presence of aspartic acid, threonine, serine, glutamate, proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, histidine, lysine, and arginine amino acids, respectively. The highest content was isoleucine at 0.60% w/w. In conclusion, the isolated amino acids from Javanese goat hair can be used as a halal supplement that serves as nutrition in the body.

Synthesis Chitosan nanoparticles from Animal Byproducts (Shrimp Shells) Characterization, Physical Properties and Toxicity of Polymeric Nanoparticles in vivo

The study included the extraction of Chitin (Ch) from shrimp shells and preparation of Chitin nanoparticles (NCh) using acid hydrolysis and ultrasound method. In addition, the preparation of chitosan (Chs) and Chitosan nanoparticles (NChs) by Deacetylation method, then we study some of the characteristics, including yield, diameter by Size Analyzer, Field Emission Scanning Electron Microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy, X-Ray Diffractometer (X-RD), Viscosity, Water Binding Capacity (WBC) and Fat Binding Capacity (FBC). The results showed, (a) decreased the percentage of yield of NChs to 8.20%, (b) the effective diameter of the natural chitosan using a Size Analyzer and was 28121.5 nm, (c) FESEM analysis revealed that the NChs displayed a nanoscale structure with diameters ranged from 20.93 - 30.20 nm (d) the degree of deacetylation (DD%) using FT-IR spectroscopy device, of NChs was (80.21%) compared to Chs 71.45%, and in addition, from the X-ray spectrum, two peaks in spectra of (Ch, NCh) and (Chs, NChs) were observed at the diffraction angles (2θ) which are (10.70-10.99) and (19.99-20.37). Results show increasing the crystallization coefficient of NCh and NChs, while viscosity, WBC and FBC of NChs decreased compared to Chs. The NChs did not show any toxic effect on human blood cells at concentrations of 100-1000 µg. ml-1.

An alternative process for bioethanol production from marine and freshwater algae using yeast for hydrolysis

This research develops a new process for production of bioethanol from marine and freshwater algae based on hydrolysis using yeast rather than the established methods of enzyme and acid hydrolysis. Yeast were isolated and adapted specifically for this process and the effectiveness of this hydrolysis was evaluated. This method was then evaluated within a full ethanol production process involving ozone pretreatment, and both hydrolysis and fermentation using yeast, under different nutrient supplementation regimes. The process effectiveness was evaluated for species of freshwater (Spirogyra hyalina) and marine (Kappaphycus alvarezii) algae. The yeast-based hydrolysis method outperformed acid and enzyme hydrolysis for both species of freshwater and marine algae, with particularly significant results for the freshwater algae. In the whole of process treatment, the yeast-based hydrolysis approach was effective when combined with ozone pretreatment for marine algae, and without any pretreatment for freshwater algae. The highest ethanol yield was achieved through fermentation with a yeast extract supplement present. These results indicate that ozone pretreatment, hydrolysis using yeast, and fermentation with the use of yeast extract as a nutrient are promising methods for economic ethanol production from seawater algae, and for freshwater algae where ozone pretreatment is not required.

Physicochemical Properties of Cellulose Nanocrystals Extracted from Postconsumer Polyester/Cotton-Blended Fabrics and Their Effects on PVA Composite Films.

The utilisation of cotton waste as precursors in the synthesis of nanocrystalline cellulose has gained significant attention. This approach suggests a sustainable solution to address the growing concern of textile waste accumulation while simultaneously producing a valuable material. The main aim of this study is to examine the properties of cellulose nanocrystals (CNCs) obtained from postconsumer polyester-cotton waste and assess the effect of different fabric structures on the extraction and these properties. To acquire nanocellulose, a thorough decolourisation pretreatment process was utilised, which involved the treatment of polyester-cotton waste with sodium dithionite and hydrogen peroxide. Consequently, the postconsumer material was then treated with an acid hydrolysis method employing a 64% (v/v) sulphuric acid solution at 50 °C for 75 min, resulting in the formation of CNCs with average yield percentages ranging from 38.1% to 69.9%. Separation of the acid from the CNC was facilitated by a centrifugation process followed by dialysis against deionised water. Uniform dispersion was then achieved using ultrasonication. A variety of analytical techniques were employed to investigate the morphological, chemical, thermal, and physical properties of the isolated CNCs. Among these techniques, attenuated total reflection-Fourier-transform infrared spectroscopy (ATR-FTIR), energy-filtered transmission electron microscopy (EF-TEM), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) were utilised to analyse the CNCs. The findings indicated that the separated CNCs exhibited a rod-shaped morphology, measuring between 78 and 358 nm in length and 5 and 16 nm in diameter, and also exhibited high crystallinity (75-89%) and good thermal stability. The extracted CNCs were mixed with polyvinyl alcohol (PVA) and glycerol to assess their reinforcing effect on plastic films. The prepared composite film exhibited improved mechanical properties and thermal stability. Incorporating CNCs led to a 31.9% increase in the tensile strength and a 42.33% rise in the modulus of elasticity. The results from this research proved that CNCs can be extracted from postconsumer mixed fabrics as a potential solution to effectively address the mounting concerns surrounding waste management in the textile industry and also provide avenues for enhancing the qualities of eco-friendly composite films.

Simultaneous extraction of five heavy metal ions from root vegetables via dual-frequency ultrasound-assisted enzymatic digestion

The dual-frequency ultrasound-assisted enzymatic digestion (DUED) technique was developed for synchronous green extraction of five heavy metal ions in root vegetables. The combination of α-amylase, cellulase, and papain showed significant advantageous in extracting heavy metal ions. Under optimized dual-frequency ultrasonic conditions, the extraction rates of Cr, As, Cd, Pb, and Hg in carrots reached 99.04%, 105.88%, 104.65%, 104.10%, and 103.13% respectively. And the extraction process is highly efficient, completing in just 15 min. Compared to conventional microwave-assisted acid hydrolysis method, this technique eliminates the need for high-temperature concentrated acid, enhancing its environmental sustainability while maintaining mild reaction conditions, making it ideal for biosensors application. Additionally, simultaneous extraction and detection of four heavy metals in lotus roots were successfully achieved by using DUED and a fluorescent paper-based microfluidic chip. The obtained results are consistent with those obtained using conventional methods.

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.

Unveiling structure and performance of tea-derived cellulose nanocrystals

In this study, cellulose was extracted from black tea residues to produce black tea cellulose nanocrystals (BT-CNCs) using an optimized acid hydrolysis method. The structure and performance of BT-CNCs were evaluated. The results showed that the optimal conditions for acidolysis of BT-CNCs included a sulfuric acid concentration of 64 %, a solid-liquid ratio of 1:18 (w/v), a hydrolysis temperature of 45 °C, and a hydrolysis time of 50 min. The optimization process resulted in a 44.8 % increase in the yield of BT-CNCs, which exhibited a crystallinity of 68.57 % and were characterized by the typical cellulose I structure. The diameters of the particles range from 5 to 45 nm, and they exhibit aggregation behavior. Notably, BT-CNCs demonstrated excellent storage stability, and the Tyndall effect occurred when exposed to a single beam of light. Although the thermal stability of BT-CNCs decreased, their primary thermal degradation temperature remained above 200 °C. The colloidal nature of BT-CNCs was identified as a non-Newtonian fluid with “shear thinning” behavior. This study introduces a novel method to convert tea waste into BT-CNCs, increasing the yield of BT-CNCs and enhancing waste utilization. BT-CNCs hold promise for application in reinforced composites, offering substantial industrial value.