Extraction Yield Research Articles

Ultrasonic-assisted extraction of polyphenolics from Schrebera swietenioides Roxb.: An optimization using response surface methodology

Schrebera swietenioides Roxb is an important medicinal plant used for the treatment of various diseases by the indigenous communities. However, this plant is still underexplored in the modern scientific era. Specifically, the leaves of the plant are reported to contain various medicinal properties such as antioxidant, antimicrobial, anti-inflammatory, and antipyretic activity. Herewith, the present work demonstrates and optimizes the extraction process usingan ultrasonic system and comopared the results with conventional extraction methods. Optimization was performed by combining first and second-order polynomial designs at different levels using Plackett-Burman and Central-Composite designs. A total of 31 experiments were conducted at different levels, including ultrasonic power (10–40 %), solvent-to-sample ratio (20–50 mL/g), solvent concentration (50–80 %), and HCl normality (0.2–1 N). The findings of the study suggest a significant (p<0.05) influence of extraction parameters on the extraction yield of the response variables, including total phenol (TPC), total flavonoid (TFC), total tannin (TTC), and the antioxidants activity. Further, the predicted values demonstrated good agreement with the experimental values, exhibiting a high (R2>95%) coefficient of determination and a non-significant lack of fit. At the optimized condition, the experimental values of TPC, TFC, TTC and antioxidants (DPPH, ABTS, FRAP) activity were found near the model predicted values. The HPLC-PDA analysis identified ten polyphenolic compounds, among which rutin hydrate (12.991±0.003 mg/g DW), followed by phloridzin (6.660±0.001 mg/g DW), and chlorogenic acid (3.380±0.008 mg/g DW) were the most prominent compounds. Furthermore, the optimized extract showed effective antibacterial activity against Bacillus subtillis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus species. In conclusion, the obtained results indicate that the proposed optimization strategy can be utilized to enhance the yield of polyphenolics from the target species with possibility of its application in therapeutics values.

Isoflavone-rich extracts from okara using supercritical fluid extraction: Kinetic modeling and characterization

The lipid fraction and bioactive compounds from okara, a by-product of soybean processing, have been extracted by supercritical fluid extraction. The effect of operating parameters, pressure (20–40 MPa), temperature (40–80 ºC), and cosolvent usage (0–10 %wt. ethanol), on the extraction kinetics has been investigated, satisfactorily correlating the experimental data to the Sovová’s model. Extraction yield by SFE ranged from 0.1014 g extract/g insoluble solid (IS) at 20 MPa and 80 ºC to 0.1081 g extract/g IS at 30 MPa and 60 ºC (from 9.2 to 9.8 g extract/100 g okara, respectively), similar to Soxhlet extraction with n-hexane (9.2 ± 0.2 g extract/100 g). Pressure positively affected the initial extraction rate, which also increased with temperature except for the lowest pressure of 20 MPa, exhibiting a typical cross-over behavior. The use of ethanol as cosolvent promoted the extraction of phenolic compounds and isoflavones, and was less important in the extraction of tocopherols. Extraction yield using ethanol increased up to 0.1100 g extract/g IS at 40 MPa and 40 ºC. As expected, the higher content of bioactive compounds in the sc-CO2 + ethanol extracts positively affected the antioxidant capacity, with the maximum found at 20 MPa, 40 ºC and 10 %wt. ethanol.

Ekstraksi Daun Kejibeling (Strobilanthes crispus) dengan Metode Continuous Ultrasound-Assisted Enzymatic Extraction: Pengaruh Temperatur dan Konsentrasi Enzim

Continuous ultrasound-assisted enzymatic extraction (CUAEE) method has become a promising technique for extracting bioactive compounds from plant materials. In this study, the extraction of kejibeling (Strobilanthes crispus) leaves was carried out using the CUAEE method to optimize the extract yield. The experimental design involved extraction parameters including leaf particle size (d ≤0,177 mm), ethanol concentration (50%), extraction time (180 minutes), and varying parameters such as temperature (30 °C, 40 °C, 50 °C, and 60 °C), as well as cellulase enzyme concentration of 3% and 5%. The results showed that the optimal conditions for CUAEE were achieved at a temperature of 60 °C with an enzyme-solid ratio of 5%, producing a total phenolic content (TPC) of 12,097 mg EAG/g dry leaf powder and a total flavonoid content (TFC) of 2,291 EK/g dry leaf powder. The data obtained indicate that the continuous ultrasound-assisted enzymatic extraction method has the potential for large-scale production of phenolic acids and flavonoids.

A water-soluble mycelium polysaccharide from Monascus pilosus: Extraction, structural characterization, immunomodulatory effect and yield enhanced by overexpression of UGE gene

Mycelium polysaccharide (MPP) from Monascus pilosus with the compositions of glucose, galactose, mannose, glucosamine hydrochloride, rhamnose and arabinose, was obtained using alkaline extracting, and subsequently three purified components (MPP-0, MPP-0.1 and MPP-0.3) were separated. The purity and extraction volume of the MPP-0.1 fraction surpassed those of the other two groups, thus warranting its selection for subsequent experimental investigations. The sample MPP-0.1, with an average molecular weight of 3.7776 × 104 Da, exhibited exceptional thermal stability up to 170 °C. The main glycosidic linkage pattern of MPP-0.1 was structured as→[4)-α-D-Glcp-(1]6 → 4)-α-D-Glcp-(1 → [2)-α-D-Manp-(1]5 → 2)-α-D-Manp-(1 → 5)-β-D-Galf-(1 → 3)-β-D-Galf (1 → 3)-β-D-Galf-(1 → 3)-β-D-Galf-(1→, and branched Glcp, Manp, Galf fragments were connected with the main chain through →4, 6)-α-D-Glcp-(1→, →2, 6)-α-D-Manp-(1 → and →3, 6)-β-D-Galf-(1→. Besides, the up-regulated levels of Nitric oxide (NO), Tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-1β (IL-1β) and other pro-inflammatory cytokines along with increased phagocytic activity revealed that MPP-0.1 has significant immunomodulatory effect, and can significantly enhance the proliferation and activation of RAW264.7 cells. Finally, the gene UGE (UDP-glucose 4-epimerase) was overexpressed in M. pilosus to increase the MPP production. Results showed that the biomass of the recombinant strain exhibited a remarkable increase of approximately 62.56 ± 1.50 % compared to that of the parental strain, and the extraction yield of MPP increased significantly by 83.19 ± 4.56 %.

Synergistic effect of drying methods and ultrasonication on natural deep eutectic solvent extraction of phytochemicals from African spinach (Amaranthus hybridus) stem.

The study evaluated the combined effects of drying methods (air drying [AD], hot AD [HAD], microwave drying [MD], and freeze-drying [FD]) and ultrasonication parameters (sonication temperature [STemp]: 40, 50, and 60°C) and heating time (STime: 60 and 120min) on natural deep eutectic solvent (NADES) extraction of phytochemicals from Amaranthus hybridus stem. Increasing the STemp increased the extraction yield (ECY) of the phytochemicals for all drying methods but increase in the heating time reduced the ECY slightly. MD combined with 60°C ST showed the highest ECY (53%), whereas HAD combined with 40°C ST had the lowest ECY (18%). At 60min heating time, increasing the ST from 40 to 50°C increased the total phenolic content (TPC) in the extract for most drying methods except MD, and a sonication time of 120min showed a slightly higher TPC, especially for MD samples. At 60min sonication, total flavonoid content (TFC, 800mgQE/g) was highest for AD plus 50°C ST and lowest for AD combined with 60°C (100mgQE/g), whereas for 120min sonication, MD and AD with 50°C showed the highest TFC (690mgQE/g). FD retained better some of the vitamins (thiamine, riboflavin, niacin) but MD retained better vitamin C. The antioxidant capacity was not so much different among the drying methods except for FD, which showed lower values. These results provide a theoretical basis for the synergistic applications of drying and ultrasonication during NADES extraction of phytochemicals from Amaranthus hybridus.

Determination of drugs of abuse and metabolites in plasma microsamples by LC-MS/MS after microQuEChERS extraction.

Aim: Identifying drugs of abuse and their metabolites in plasma is vital in both forensic and clinical toxicology. While the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method offers an efficient approach to sample preparation, its application is complex due to the wide-ranging properties of target analytes and the challenges posed by biological matrix interferences. This study aims to develop a microQuEChERS approach for the quantification of 14 drugs of abuse and metabolites utilizing minimal sample and solvent volumes.Methods: The microQuEChERS method involved using 10μl plasma samples, 25mg of a salt mixture and 150μl of acetonitrile. Extracts were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), with a 7.5min run. The assay was validated according to bioanalytical guidelines.Results: The accuracy was 96.8-112.4%. The within-assay precision was within 2.0-8.9% and the between-assay precision was within 3.2-8.2%. Matrix effects were found to range from -5.7 to 13.5%. The extraction yield was higher than 74.7%.Conclusion: This study described a microQuEChERS sample preparation approach for determining drugs of abuse and metabolites using plasma microsamples and LC-MS/MS. The approach is efficient, environmentally friendly and suitable for scenarios with limited amounts of biological samples.

Ultrasonic-assisted extraction, structural analysis and antioxidative mechanism of polysaccharide from sunflower disc

The crude sunflower disc polysaccharide (SDP) was obtained by using ultrasonic assist hot water extraction. Homogeneous SDP was separated by DEAE-cellulose column and Sephacryl S-400 HR column. Its physical properties and antioxidant mechanism was studied. Results showed that extraction yield of SDP was 15.3 %, total sugar was 91.3 %, weight molecular weight (Mw) was7.46 × 103 Da, number-average molecular weight (Mn) was 6.16 × 103 Da and polydispersion coefficient (Mw/Mn) was 1.21. SDP was composed of galactose (Gal), fucose (Fuc), xylose (Xyl), glucose (Glc), arabinose (Ara), rhamnose (Rha), glucuronic acid (Gle-UA) and galacturonic acid (Ga-UA), and the ratio of substance were 1.77∶2.00∶4.55∶8.44∶9.57∶14.26∶2.13∶57.28. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results showed that smooth surface and structure of SDP was relatively dense, and some crystallization existed, but the crystallization was weak. Two-dimensional structure of SDP showed that the main chain →4)-α-d-GalpA-(1→, →3)-α-l-Araf-(1→, →2)-α-l-Rhap-(1→, →2, 4)-α-l-Rhap-(1→, →2, 4)-α-d-GlcpA-(1→ and →3, 6)-β-d-Galp-(1→ interconnection form. Results of in vitro and in vivo of SDP and its derivatives showed that a good antioxidant activity. In vitro antioxidant activity, the scavenging rates of ABTS+, ·OH, DPPH and superoxide anions were 95.8 %, 93.9 %, 93.6 % and 92.1 %, respectively, when treated with 3.2 mg/mL of SDP solution. The preliminary antioxidative mechanism results showed that SDP had a regulatory effects on the down-regulation of Nrf2, HO-1 and NQO1 proteins in RAW264.7 cells. Preliminary pharmacokinetic analysis showed that the SDP could be absorbed orally and reached its peak concentration in the blood at about 2 h. The content of polysaccharide in blood reached the peak value at 30 min and reached the lowest value at 8 h after intravenous injection.

Overview and Toxicity Assessment of Ultrasound-Assisted Extraction of Natural Ingredients from Plants.

In different food technology unit operations, toxicity can be increased due to unwanted side reactions and is typically associated with the increased thermal energy that facilitates the latter. Authorities in food technology have not provided clear guidelines on using ultrasound (US), but they also have not prohibited its use in food processing. In this study, the source materials and ultrasound-assisted reactions reported in the literature were reviewed to investigate potential side reactions in ultrasound-assisted extraction (UAE). Industrial or pilot-scale processes published in the open literature and in industry patents were also examined. UAE is a highly effective extraction method that significantly increases extraction yields. According to the literature, there is no direct evidence of the formation of toxic compounds from natural food ingredients caused by UAE. However, experimental studies are urgently needed to assess the potential accumulation of toxic substances, especially in the case of certain plants.

Assessment of ethanolic extract of Dittrichia viscosa from Kardoussa Douar region of Taza in Morocco as antioxidant and green inhibitor for carbon steel corrosion in acidic medium

This study targeted evaluating the anticorrosive and antioxidative characteristics of Dittrichia viscosa (ZS-OH) extract. ZS-OH was first extracted by deploying a soxhlet and characterized by chromatographic analysis (GC/MS). In addition, a quantitative assessment of the total phenolic (TPC) and flavonoids (FC) content of the ZS-OH extract, as well as phytochemical analyses, were carried out. Antioxidant testing was conducted using the bioassay: 2,2-diphenyl-1-picrylhydrazyl (DPPH). The ability of ZS-OH extract to stymie the corrosion of carbon steel in 1.0 M HCl was considered through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). ZS-OH extract yield was 4.73 %, and GC-MS revealed 32 distinct chemicals. Neryl isovalerate (29.8 %), 1,10-di-epi-Cubenol (25.4 %), and 2,5-dimethoxy-p-cymene (11.6 %) made up the majority of the ZS-OH extract. The electrochemical results reveal that the ZS-OH extract acts as a mixed-type with an inhibition efficiency of up to 96.8 % at 500 ppm under 303 K. Surface analyses using SEM/EDS confirmed the formation of the protective layer of ZS-OH extract molecules on the C-S surface. The three major components are fully optimized in the DFT through the B3LYP functional and 6–311++G(d,p) basis sets. Molecular dynamics simulation data show the molecules of ZS-OH extract oriented beneficially on metal surfaces, providing a high surface coverage, and thus, a high inhibition performance.

Extraction of Flavonoids from Parasitic plant Macrosolen cochinchinensis using Ultrasound-Assisted Extraction: An Optimization Approach

The parasitic plant Macrosolen cochinchinensis (Lour.) VAN Tiegh, commonly found parasitizing mango trees, contains flavonoid compounds with potential anticancer properties. This study aims to optimize the extraction of flavonoids from M. cochinchinensis using the Ultrasonic Assisted Extraction (UAE) method. Three extraction parameters were investigated to determine the best conditions for maximizing extract yield and flavonoid concentration. The parameters considered for the UAE technique were different ethanol concentrations (30%, 70%, and 96%), extraction times (15, 30, and 45 minutes), and solvent-to-sample ratios (1:10, 1:20, and 1:30). The study used Response Surface Methodology (RSM) to identify the optimal extraction conditions. The analysis using RSM indicated that the highest extraction yield (10%) was achieved with a sample-to-solvent ratio of 1:30, 30% ethanol concentration, and an extraction time of 45 minutes. The highest flavonoid content (457.96 mg QE/g extract) was obtained with a solid-to-liquid ratio between 1:20 and 1:30, using 65 to 80% ethanol solvent and an extraction time of 45 minutes. These results suggest that these parameters extract flavonoid compounds from M. cochinchinensis leaves.

Synthesis and properties of the natural ultraviolet absorber gadusol in Komagataella phaffii

Gadusol, an efficient natural ultraviolet (UV) absorbing substance with antioxidant capacity, is ubiquitous in aquatic organisms such as microorganisms, algae, and fish eggs. In order to address issues such as its low natural extraction yield and environmental unfriendliness, we introduced the gadusol synthesis pathway from zebrafish into Komagataella phaffii and successfully constructed the recombinant strain capable of synthesizing gadusol. The xylose assimilation genes derived from Scheffersomyces stipitis were further introduced into the recombinant strain to increase the content of the key substrate sedoheptulose 7-phosphate (S7P). The results showed that the utilization of xylose was an effective strategy to increase the yield of gadusol. In the medium with only xylose as the substrate, the yield of gadusol reached 141.8 mg/L (32.3 mg/g dry cell weight, DCW), which was about 46 times of that in the medium with only glucose as the substrate. The product showed obvious absorption in the range of 275-305 nm, with the maximum absorption at 290 nm. Moreover, the product demonstrated antioxidant capacity. After reaction for 5 h, the ferric ion reducing antioxidant power (FRAP), 2, 2'-azino- bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging rates changed by 90.83%, 25.50%, and 131.80%, respectively, which suggested that the product may be used as a long-acting antioxidant. This study demonstrated the great potential of K. phaffii as a chassis for the biosynthesis of natural UV absorbers. The biosynthesized gadusol has good UV absorption and antioxidant properties, which provides a theoretical basis for the industrial production and application of gadusol.

Microalgae Flocculation: Assessment of Extraction Yields and Biological Activity

Downstream costs represent one of the main obstacles to enabling microalgae to become widespread. The development of an economical, easily scaled-up strategy could reduce the overall process costs. Here, different flocculants were tested on different microalgae strains and a cyanobacterium. The results indicate that flocculation could be an alternative to centrifugation, as CaCl2 induced a complete flocculation of green and red marine strains (96 ± 4% and 87.0 ± 0.5%, respectively), whereas Chitosan was the only agent able to induce flocculation on the cyanobacterium (46 ± 1%). As for the thermoacidophilic red microalga, 100% flocculation was achieved only by increasing the pH. Carotenoids were extracted from the flocculated biomass, and the strategy improved with the use of the wet biomass. The results indicate that flocculation does not affect carotenoid yield, which is at least the same than that obtained upon centrifugation and extraction from the wet biomass. Then, for the first time, the biological activity of the extracts obtained from the flocculated biomasses was evaluated. The results indicate that only the green microalga extract shows increased antioxidant activity. In conclusion, this work highlights that a general downstream procedure cannot be developed for microalgae strains but should be rationally tailored.

Choosing the optimal technology for obtaining Crocus alatavicus extract with a high content of flavonoids and carotenoids

In recent years, there has been a significant increase in demand for herbal medicines, due to the growing interest of consumers in natural and safe alternatives to synthetic medicines. In response to these trends, manufacturers are focusing on developing new formulas and extraction technologies to meet the increased demand for herbal medicines. Modern extraction methods make it possible to efficiently extract secondary metabolites from plant raw materials, maintaining an almost complete chemical composition and ensuring a high yield of extractives. The possibility of regulating the concentration of extracted biologically active substances during the process opens up new prospects for the use of plant raw materials as basic pharmaceutical substances. It was found that all the studied plant species of the genus Crocus L. demonstrate antioxidant, anti-inflammatory and cardioprotective activity. Crocus alatavicus, which is a representative of the flora of Kazakhstan, is of particular interest. The purpose of this study is to select the optimal extraction method for obtaining extracts with the maximum content of flavonoids and carotenoids from the aboveground part of Crocus alatavicus. The study of the technological parameters of obtaining an extract from this plant active substance is of practical importance for the further development of medicines and the formation of a scientific justification for their use.

Development and Evaluation of Oromucosal Spray Formulation Containing Plant-Derived Compounds for the Treatment of Infectious and Inflammatory Diseases of the Oral Cavity.

According to data in the literature, natural products and essential oils are often used in dental practice. To develop a new oromucosal spray for the treatment of infectious and inflammatory diseases of the oral cavity, clove CO2 extract and essential oils of lavender and grapefruit were used as active pharmaceutical ingredients. Clove extract was obtained by the method of subcritical extraction from various raw materials, the choice of which was based on the yield of the CO2 extract and the study of its phytochemical and microbiological properties. Based on the results of microscopic and diffraction analyses, the rational time of ultrasonic exposure for the emulsion of active pharmaceutical ingredients was established. Mucoadhesive polymers were used as stabilizers of the two-phase system and prolongators. This article discusses the impact of the type and concentration of mucoadhesive polymers on the stability of the emulsion system; the viscous, textural, adhesive, and film characteristics of oromucosal spray; and the parameters determining sprayability.

In Vitro Potential of Antioxidant Extracts from Gracilaria gracilis Cultivated in Integrated Multi-Trophic Aquaculture (IMTA) for Marine Biobased Sector

This study aimed to evaluate the antioxidant activity of bioactive compounds extracted from Gracilaria gracilis cultivated in an integrated multi-trophic aquaculture (IMTA) system by different extraction solvents and to investigate the potential capacity of the extracts in cellular systems against environmental pollutants. The global yields, total polyphenol contents, and antioxidant activity were assessed on G. gracilis by DPPH radical scavenging activity, comparing the antioxidant extraction efficiency of the different solvents (ethanol 80%, acetone 70%, N-hexane, and water). Ethanol extract, granted by the highest extractive yield and antioxidant capacity, was tested in vitro in the Sparus aurata fibroblast (SAF-1) cell line to evaluate its protective role against oxidative stress induced by the chemical flame retardant 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47). The results demonstrate that the cells pretreated with G. gracilis extract were protected against oxidative stress and had improved cell viability, cellular antioxidant defense system, and cell cycle control, as demonstrated by the gene expression on some biomarkers related to the cell cycle (p53) and oxidative stress (nrf2, sod, and cat). These results confirm that bioactive compounds obtained from seaweeds cultivated in IMTAs could contribute to producing high-value ingredients that are able to counteract environmental stressors, for the growth of the marine biobased industrial sector and the expansion of new value chains.

Response surface optimization for supercritical carbon dioxide extraction of Korarima (Aframomum corrorima) seed oil and its antibacterial activity evaluation

Oils extracted from natural plants are valuable resources because of their diverse biocidal activity against microorganisms. This paper reports, for the first time, supercritical CO2 extraction of oil from Korarima (Aframomum corrorima) seeds and its antibacterial activity evaluation. The influences of pressure, temperature, and extraction time on the yield of supercritical CO2-extracted oil (scCO2-extracted oil) were optimized using the Response Surface Methodology. Under the optimal extraction conditions of 46 °C, 15.5 MPa, and 147 min, the extraction yield reached 1.60±0.04 %, consistent with the theoretical value of 1.58 %. The compositions of the scCO2-extracted oil were identified by GC-MS, primarily consisting of nerolidol (33.97–41.20 %), geraniol (23.08–24.50 %), and α-terpinene (8.90–9.06 %). The oil exhibited significant antibacterial activity against Staphylococcus. aureus with a minimum inhibitory concentration of 1 mg·mL−1. This study highlights the potential applications of supercritical CO2 extraction technology for extracting Korarima seed oil and its use as an antibacterial ingredient in cosmetics and pharmaceuticals.

Electron beam irradiation coupled ultrasound-assisted natural deep eutectic solvents extraction: A green and efficient extraction strategy for proanthocyanidin from walnut green husk

Proanthocyanidin (PAC) is recognized as a potent natural antioxidant that prevents various diseases. As societal awareness increases, eco-friendly and efficient natural product extraction technologies are gaining more attention. In this study, an electron beam irradiation (EBI) coupled with ultrasound-assisted natural deep eutectic solvents (NADES) extraction method was developed to enable the green and highly efficient extraction of PAC from walnut green husk (WGH). NADES, prepared with choline chloride and ethylene glycol, demonstrated excellent extraction capacity and storage stability for PAC. Molecular dynamics simulations elucidated the high compatibility between NADES and PAC, attributed mainly to a higher SASA value (207.85 nm2), a greater number of hydrogen bonds (330.99), an extended hydrogen bonding lifetime (4.54 ps), and lower inter-molecular interaction energy. Based on these findings, the optimal conditions (13 kGy EBI, 42 mL/g liquid-solid ratio, 38 °C extraction temperature, 70 min extraction time) resulted in a maximum PAC extraction yield of 56.34 mg/g. Notably, this yield was 32.93 % higher than that observed in samples not treated with EBI and ultrasound-assisted extraction (UAE). Analysis of tissue morphology, extract functional groups and thermal behavior suggested a possible mechanism for the synergistically enhanced PAC extraction by the EBI-NADES-UAE method. Additionally, the PAC extracted using the NADES by the EBI coupled with ultrasound-assisted method exhibited outstanding antioxidant activity (comparable to Vc), digestive enzyme inhibition (IC50: 17–0.61 mg/mL), and anti-glycation capacity (IC50: 86.49 μg/mL). Overall, this work provided a green and efficient strategy for PAC extraction from WGH, elucidated the extraction mechanism and bioactivities, and offered valuable insights for potential industrial applications.

A soft processing technology for the extraction of cellulose from plant residues and agri-food wastes

In this study, cellulose was extracted from giant cane (GC), Posidonia oceanica seagrass (PO), coffee silverskin (CS), and brewer's spent grain (BSG) as alternatives to conventional sources of cellulose. The extraction protocol involved three steps: i) hemicellulose and lignin removal through alkaline hydrolysis in a 5% (w/v) NaOH solution (solid-to-liquid ratio = 1:100 g/mL, T = 25 °C, t = 2 h, ω = 300 rpm), ii) removal of organic compounds and ashes through a 95% (v/v) ethanol solution (solid-to-liquid ratio = 1:25 g/mL, T = 25 °C, t = 0.5 h, ω = 500 rpm), and iii) double bleaching in a 1% (w/v) acidic (pH = 4) NaClO2 solution (solid-to-liquid ratio = 1:50 g/mL, T = 90 °C, t = 1.5 h, ω = 500 rpm). Yield, purity, crystallinity degree, and morphology of cellulose extracted through a soft-chemical cascade process were assessed by gravimetric, infrared (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses. Averaged cellulose extraction yields of 36.4, 38.6, 23.1, and 22.2% for GC, PO, CS, and BSG were obtained, respectively. All cellulose samples had high purity, though lower than the ultra-pure bacterial cellulose, which was due to the slight contamination from unremoved hemicellulose and lignin residues. Cellulose samples exhibited similar chemical features and the typical fibril-like morphology of microcrystalline cellulose (6–13 μm in width). The versatility of the proposed extraction procedure supports the sustainable conversion of low-cost organic biomasses to valuable products with manifold industrial applications (e.g., food packaging).

Co-production of cellulose and lignin by Taguchi-optimized one-pot deep eutectic solvent-assisted ball milling pretreatment of raw oil palm leaves

This study explores an eco-friendly delignification technique for raw oil palm leaves (OPL), highlighting the optimized conditions of choline chloride-lactic acid deep eutectic solvent (DES)-mediated ball milling pretreatment to maximize the co-production yields of highly crystalline cellulose and lignin. Our five-level-four-factor Taguchi design identified the optimal reaction settings for cellulose production (85.83 % yield, 47.28 % crystallinity) as 90-minute milling, 1500 rpm, mill-ball size ratio of 30:10, ball-to-sample mass ratio of 20:1, DES-to-sample mass ratio of 3:1. Conversely, the maximal lignin extraction yield (35.23 %) occurred optimally at 120-minute milling, 600 rpm, mill-ball size ratio of 25:5, ball-to-sample mass ratio of 20:1 and DES-to-sample mass ratio of 9:1. Statistical results showed that milling frequency (p-value ≤ 0.0001) was highly significant in improving cellulose crystallinity and yield, while DES-to-sample mass ratio (p-value ≤ 0.0001) was the most impacting on lignin yield. The thermogravimetric method affirmed the elevated cellulose thermal stability, corroborating the enhanced cellulose content (40.14 % to 73.67 %) alongside elevated crystallinity and crystallite size (3.31 to 4.72 nm) shown by X-ray diffractograms. The increased surface roughness seen in micrographs mirrored the above-said post-treatment changes. In short, our optimized one-pot dual-action pretreatment effectively delignified the raw OPL to produce cellulose-rich material with enhanced crystallinity and lignin solidity.

LI-ION BATTERY RECYCLING AT PILOT SCALE: DEMONSTRATING THE RESYNTHESIS ROUTE ALSO FOR NMC-LFP MIXED BLACK MASS

The hydrometallurgical recycling of end-of-life Li-ion batteries constitutes a sustainable path for the integral recovery of battery components. However, the heterogeneity of electrode materials constitutes a limitation for process optimization that must provide robust and flexible strategies. In this work, the preliminary results obtained as part of the demonstration activities of the LIFE DRONE project are reported with particular attention to the possibility of integrating the recycling process based on the resynthesis of NMC (Nickel Manganese Cobalt) cathodes with the treatment of mixed black mass also containing LFP (Lithium Ferrous Phosphate) electrodic powders. The experimental results obtained highlight the possibility of leaching NMC black mass in the absence of hydrogen peroxide when NMC-LFP mixtures are used with almost quantitative extraction yields of metals. In particular, working without H2O2 at 60°C for 3 h the following yields of extraction were obtained: 89% for Ni, 69% for Mn, 89% for Co, 91% for Li, 90% for Fe, 100% for P, 56% for Al and 32% for Cu. Furthermore, the experimental data showed that by varying the pH of the leach liquor, it is possible to separate selectively iron phosphate by quantitative precipitation (100% for Fe, 100% for P and 60% for Al) before proceeding with NMC resynthesis.