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1.
Int J Biol Macromol ; 259(Pt 1): 129222, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38185307

ABSTRACT

The substantial nutritional content and diversified biological activity of plant-based nutraceuticals are due to polyphenolic chemicals. These chemicals are important and well-studied plant secondary metabolites. Their protein interactions are extensively studied. This relationship is crucial for the logical development of functional food and for enhancing the availability and usefulness of polyphenols. This study highlights the influence of protein types and polyphenols on the interaction, where the chemical bindings predominantly consist of hydrophobic interactions and hydrogen bonds. The interaction between polyphenolic compounds (PCs) and digestive enzymes concerning their inhibitory activity has not been fully studied. Therefore, we have examined the interaction of four digestive enzymes (α-amylase, pepsin, trypsin, and α-chymotrypsin) with four PCs (curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone) through in silico and in vitro approaches. In vitro plate assays, enzyme kinetics, spectroscopic assays, molecular docking, and simulations were performed. We observed all these PCs have significant docking scores and preferable interaction with the active site of the digestive enzymes, resulting in the reduction of enzyme activity. The enzyme-substrate binding mechanism was determined using the Lineweaver Burk plot, indicating that the inhibition occurred competitively. Among four PCs diosmin and morin has the highest interaction energy over digestive enzymes with IC50 value of 1.13 ± 0.0047 and 1.086 ± 0.0131 µM. Kinetic studies show that selected PCs inhibited pepsin, trypsin, and chymotrypsin competitively and inhibited amylase in a non-competitive manner, especially by 2',3',4'-trihydroxychalcone. This study offers insights into the mechanisms by which the selected PCs inhibit the enzymes and has the potential to enhance the application of curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone as natural inhibitors of digestive enzymes.


Subject(s)
Curcumin , Diosmin , Molecular Docking Simulation , Pepsin A/metabolism , Trypsin/metabolism , Curcumin/pharmacology , Kinetics , Polyphenols/pharmacology , Flavonoids/pharmacology , Flavonoids/chemistry , alpha-Amylases/metabolism , alpha-Glucosidases/metabolism
2.
J Mater Chem B ; 11(40): 9597-9629, 2023 10 18.
Article in English | MEDLINE | ID: mdl-37740402

ABSTRACT

Polyesters based on polyols have emerged as promising biomaterials for various biomedical applications, such as tissue engineering, drug delivery systems, and regenerative medicine, due to their biocompatibility, biodegradability, and versatile physicochemical properties. This review article provides an overview of the synthesis methods, performance, and biodegradation mechanisms of polyol-based polyesters, highlighting their potential for use in a wide range of biomedical applications. The synthesis techniques, such as simple polycondensation and enzymatic polymerization, allow for the fine-tuning of polyester structure and molecular weight, thereby enabling the tailoring of material properties to specific application requirements. The physicochemical properties of polyol-based polyesters, such as hydrophilicity, crystallinity, and mechanical properties, can be altered by incorporating different polyols. The article highlights the influence of various factors, such as molecular weight, crosslinking density, and degradation medium, on the biodegradation behavior of these materials, and the importance of understanding these factors for controlling degradation rates. Future research directions include the development of novel polyesters with improved properties, optimization of degradation rates, and exploration of advanced processing techniques for fabricating scaffolds and drug delivery systems. Overall, polyol-based polyesters hold significant potential in the field of biomedical applications, paving the way for groundbreaking advancements and innovative solutions that could revolutionize patient care and treatment outcomes.


Subject(s)
Polyesters , Polymers , Humans , Polyesters/chemistry , Polymers/chemistry , Biocompatible Materials/chemistry , Biodegradation, Environmental
3.
J Clin Med ; 12(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37445470

ABSTRACT

(1) Background: We aimed to explore the associations between menopause, postmenopausal hormone therapy, and metabolic syndrome in a large community-based group of Asian women. (2) Methods: This is a cross-sectional study in which we enrolled women aged 30 to 70 years with sufficient information about menopausal status from the Taiwan Biobank. The definition for metabolic syndrome used in this study aligns with the Bureau of Health Promotion's (Taiwan) proposed definition. (3) Results: A total of 17,460 women were recruited. The postmenopausal group had a higher metabolic syndrome prevalence (30% vs. 14%) and 1.17 times higher odds ratio (OR) than the premenopausal group (95% confidence interval [CI] = 1.02 to 1.33). Regarding the types of menopause, surgical menopause was associated with metabolic syndrome (OR = 1.40; 95% CI = 1.20 to 1.63); however, natural menopause was not associated with metabolic syndrome. Interestingly, postmenopausal hormone therapy was associated with a lower risk of metabolic syndrome in the women with natural menopause (OR = 0.79; 95% CI = 0.70 to 0.89), but not in those with surgical menopause. (4) Conclusions: Our results suggest that menopause is associated with an increased prevalence of metabolic syndrome, while postmenopausal hormone therapy is associated with a lower prevalence of metabolic syndrome in women with natural menopause.

4.
Polymers (Basel) ; 15(8)2023 Apr 21.
Article in English | MEDLINE | ID: mdl-37112112

ABSTRACT

In this study, butadiene sulfone (BS) was selected as an efficient electrolyte additive to stabilize the solid electrolyte interface (SEI) film on the lithium titanium oxide (LTO) electrodes in Li-ion batteries (LIBs). It was found that the use of BS as an additive could accelerate the growth of stable SEI film on the LTO surface, leading to the improved electrochemical stability of LTO electrodes. It can be supported by the BS additive to effectively reduce the thickness of SEI film, and it significantly enhances the electron migration in the SEI film. Consequently, the LIB-based LTO anode in the electrolyte containing 0.5 wt.% BS showed a superior electrochemical performance to that in the absence of BS. This work provides a new prospect for an efficient electrolyte additive for next-generation LIBs-based LTO anodes, especially when discharged to low voltage.

5.
Crit Rev Anal Chem ; 53(8): 1828-1839, 2023.
Article in English | MEDLINE | ID: mdl-35201946

ABSTRACT

Biomarkers are biological molecules associated with physiological changes of the body and aids in the detecting the onset of disease in patients. There is an urgent need for self-monitoring and early detection of cardiovascular and other health complications. Several blood-based biomarkers have been well established in diagnosis and monitoring the onset of diseases. However, the detection level of biomarkers in bed-side analysis is difficult and complications arise due to the endothelial dysfunction. Currently single volatile organic compounds (VOCs) based sensors are available for the detection of human diseases and no dedicated nanosensor is available for the elderly. Moreover, accuracy of the sensors based on a single analyte is limited. Hence, breath analysis has received enormous attention in healthcare due to its relatively inexpensive, rapid, and noninvasive methods for detecting diseases. This review gives a detailed analysis of how biomarker imprinted nanosensor can be used as a noninvasive method for detecting VOC to health issues early using exhaled breath analysis.


Subject(s)
Volatile Organic Compounds , Humans , Aged , Volatile Organic Compounds/analysis , Biomarkers , Breath Tests/methods
6.
Sci Rep ; 12(1): 20607, 2022 11 29.
Article in English | MEDLINE | ID: mdl-36446892

ABSTRACT

To introduce image characteristics of double-chambered right ventricle on cardiac computed tomography and set a diagnostic criterion for the diagnosis. We retrospectively collected and measured the right ventricular constrictive ratio on computed tomography images in children who had simple ventricular septal defects in the past 10 years, because double-chambered right ventricle is often associated with ventricular septal defects. The right ventricular constrictive ratio was defined as the subinfundibular cross-sectional intraluminal area during end-systole divided by the area during end-diastole in the same patient. We compared the right ventricular constrictive ratio between subjects with concomitant double-chambered right ventricle and those without. 52 children were included, and 23 (44.2%) of them have concomitant double-chambered right ventricle. In most cases (n = 21; 91.3%), the hypertrophied muscular bundles occur just inferior to the level of the supraventricular crest in the right ventricle. Mean right ventricular constrictive ratio in patients with double-chambered right ventricle (15%) was significantly smaller than that without (29%). A cut-off value of a right ventricular constrictive ratio less than 20.1% was established to diagnose double-chambered right ventricle with an 89.7% sensitivity and 78. 3% specificity. Right ventricular constrictive ratio can be a valuable asset for the preoperative diagnosis of double-chambered right ventricle with cardiac computed tomography.


Subject(s)
Heart Septal Defects, Ventricular , Heart Ventricles , Child , Humans , Heart Ventricles/diagnostic imaging , Cross-Sectional Studies , Retrospective Studies , Tomography, X-Ray Computed , Constriction, Pathologic
7.
J Contam Hydrol ; 249: 104048, 2022 08.
Article in English | MEDLINE | ID: mdl-35834911

ABSTRACT

In this study, the adsorption of benzoic acid and phenols in the aqueous phase by MOF-Cu adsorbent was investigated. A high-performance liquid chromatography (HPLC) device was used to analyze the concentration of contaminants in the solution. Three isotherms, Freundlich, Langmuir, and Temkin were performed for adsorption of Benzoic Acid (BA) and Phenol contaminants. Correlation factor for adsorption isotherms were fitted into Langmuir aqueous BA and Phenol would be 99.89 and 99.98%, respectively. The equilibrium adsorption capacity MOF-Cu of BA and Phenol is 636.73 and 524.42 mg/g, respectively. In this study, high contaminant adsorption with π-π interaction and hydrogen bonding leads to the high capacity of MOFCu. In addition, the increase in adsorption capacity of benzoic acid is due to the electronegative property of oxygen in the carbonyl group and the similarity of the carboxylic acid functional group with the adsorbent. The result shows, that at initial time adsorption, has been a non-linear trend. In addition, the first-order kinetic model is not a suitable option for fitting the experimental data of adsorption kinetics and the adsorption kinetics of BA and Phenol is very well compatible with the semi-second order with the correlation Factor being 99.7 and 99.78, respectively. Also, the equilibrium adsorption capacity in pseudo-second order kinetic for BA and Phenol is 613.5 and 523.56 mg/g respectively.


Subject(s)
Metal-Organic Frameworks , Water Pollutants, Chemical , Adsorption , Benzoic Acid/analysis , Hydrogen-Ion Concentration , Kinetics , Phenol/analysis , Phenol/chemistry , Phenols/analysis , Phenols/chemistry , Thermodynamics , Wastewater/chemistry , Water/analysis , Water Pollutants, Chemical/analysis
8.
Membranes (Basel) ; 12(4)2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35448399

ABSTRACT

In recent years, the emergence of disparate micro-contaminants in aquatic environments such as water/wastewater sources has eventuated in serious concerns about humans' health all over the world. Membrane bioreactor (MBR) is considered a noteworthy membrane-based technology, and has been recently of great interest for the removal micro-contaminants. The prominent objective of this review paper is to provide a state-of-the-art review on the potential utilization of MBRs in the field of wastewater treatment and micro-contaminant removal from aquatic/non-aquatic environments. Moreover, the operational advantages of MBRs compared to other traditional technologies in removing disparate sorts of micro-contaminants are discussed to study the ways to increase the sustainability of a clean water supplement. Additionally, common types of micro-contaminants in water/wastewater sources are introduced and their potential detriments on humans' well-being are presented to inform expert readers about the necessity of micro-contaminant removal. Eventually, operational challenges towards the industrial application of MBRs are presented and the authors discuss feasible future perspectives and suitable solutions to overcome these challenges.

9.
J Biomed Mater Res B Appl Biomater ; 110(10): 2217-2230, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35441779

ABSTRACT

Nanocomposites containing clay nanoparticles often present favorable properties such as good mechanical and thermal properties. They frequently have been studied for tissue engineering (TE) and regenerative medicine applications. On the other hand, poly(glycerol sebacate) (PGS), a revolutionary bioelastomer, has exhibited substantial potential as a promising candidate for biomedical application. Here, we present a facile approach to synthesizing stiff, elastomeric nanocomposites from sodium-montmorillonite nano-clay (MMT) in the commercial name of Cloisite Na+ and poly(glycerol sebacate urethane) (PGSU). The strong physical interaction between the intercalated Cloisite Na+ platelets and PGSU chains resulted in desirable property combinations for TE application to follow. The addition of 5% MMT nano-clay resulted in an over two-fold increase in the tensile modulus, increased the onset thermal decomposition temperature of PGSU matrix by 18°C, and noticeably improved storage modulus of the prepared scaffolds, compared with pure PGSU. As well, Cloisite Na+ enhanced the hydrophilicity and water uptake ability of the samples and accelerated the in-vitro biodegradation rate. Finally, in-vitro cell viability assay using L929 mouse fibroblast cells indicated that incorporating Cloisite Na+ nanoparticles into the PGSU network could improve the cell attachment and proliferation, rendering the synthesized bioelastomers potentially suitable for TE and regenerative medicine applications.


Subject(s)
Glycerol , Nanocomposites , Animals , Clay , Decanoates/pharmacology , Glycerol/pharmacology , Mice , Sodium , Tensile Strength , Tissue Engineering/methods , Urethane
10.
Sci Rep ; 12(1): 4125, 2022 03 08.
Article in English | MEDLINE | ID: mdl-35260785

ABSTRACT

We developed a computational-based model for simulating adsorption capacity of a novel layered double hydroxide (LDH) and metal organic framework (MOF) nanocomposite in separation of ions including Pb(II) and Cd(II) from aqueous solutions. The simulated adsorbent was a composite of UiO-66-(Zr)-(COOH)2 MOF grown onto the surface of functionalized Ni50-Co50-LDH sheets. This novel adsorbent showed high surface area for adsorption capacity, and was chosen to develop the model for study of ions removal using this adsorbent. A number of measured data was collected and used in the simulations via the artificial intelligence technique. Artificial neural network (ANN) technique was used for simulation of the data in which ion type and initial concentration of the ions in the feed was selected as the input variables to the neural network. The neural network was trained using the input data for simulation of the adsorption capacity. Two hidden layers with activation functions in form of linear and non-linear were designed for the construction of artificial neural network. The model's training and validation revealed high accuracy with statistical parameters of R2 equal to 0.99 for the fitting data. The trained ANN modeling showed that increasing the initial content of Pb(II) and Cd(II) ions led to a significant increment in the adsorption capacity (Qe) and Cd(II) had higher adsorption due to its strong interaction with the adsorbent surface. The neural model indicated superior predictive capability in simulation of the obtained data for removal of Pb(II) and Cd(II) from an aqueous solution.


Subject(s)
Metal-Organic Frameworks , Water Pollutants, Chemical , Water Purification , Adsorption , Artificial Intelligence , Cadmium/analysis , Hydrogen-Ion Concentration , Kinetics , Lead , Phthalic Acids , Water , Water Pollutants, Chemical/analysis , Water Purification/methods
11.
Int J Biol Macromol ; 201: 133-142, 2022 Mar 15.
Article in English | MEDLINE | ID: mdl-34998876

ABSTRACT

Eco-friendly nanocomposite aerogels were prepared as adsorbents for the removal of a model pollutant (methylene blue, MB) from water. These aerogels were comprised of hydroxyapatite (HA) nanoparticles embedded within a polymer matrix consisting of a semi-interpenetrating network of xanthan gum (XG) and polyacrylic acid (PAA). Microscopy and BET analysis showed that the aerogels formed had a nanofibrous porous microstructure with a surface area of 89 m2/g. Rheological analysis showed that the aerogels were viscoelastic materials whose elasticity increased with increasing HA concentration (up to 5 w/w%). The aerogels were effective at removing MB from water, exhibiting an adsorption capacity of 130 mg/g after 200 min. The binding of the MB to the aerogels was mainly attributed to hydrogen bonding and electrostatic attraction. A reusability test showed that the MB removal efficiency of over 86% was preserved after 10 cycles of adsorption-desorption. These results suggest that our nanocomposite aerogels may be useful for the efficient removal of anionic pollutants from wastewater and water supplies due to their ease of synthesis, cost-effectiveness, good mechanical properties, high thermal stability, and good adsorption performance.


Subject(s)
Nanocomposites , Water Pollutants, Chemical , Acrylic Resins , Adsorption , Durapatite , Methylene Blue/chemistry , Nanocomposites/chemistry , Polysaccharides, Bacterial , Wastewater , Water Pollutants, Chemical/chemistry
12.
Biotechnol Appl Biochem ; 69(2): 714-725, 2022 Apr.
Article in English | MEDLINE | ID: mdl-33751641

ABSTRACT

Overuse of antibiotics has led to the development of multidrug-resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic-resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms in presence of an external magnet. In this review, a detailed description of surface-engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review.


Subject(s)
Biofilms , Nanoparticles , Anti-Bacterial Agents/pharmacology , Magnetic Iron Oxide Nanoparticles
13.
J Biomater Sci Polym Ed ; 33(4): 443-464, 2022 03.
Article in English | MEDLINE | ID: mdl-34641773

ABSTRACT

In this study, a novel biopolymer based on poly(glycerol sebacic)-urethane (PGS-U) and its nanocomposites containing Cloisite@30B were synthesized by facile approach in which the crosslinking was created by aliphatic hexamethylene diisocyanate (HDI) at room temperature and 80 °C. Moreover, metronidazole and tetracycline drugs were selected as target drugs and loaded into PGSU based nanocomposites. A uniform and continuous microstructure with smooth surface is observed in the case of pristine PGS-U sample. The continuity of microstructure is observed in the case of all bionanocomposites. XRD result confirmed an intercalated morphology for PGSU containing 5 wt% of clay nanoparticles with a d-spacing 3.4 nm. The increment of nanoclay content up to 5%, the ultimate tensile stress and elastic modulus were obtained nearly 0.32 and 0.83 MPa, which the latter was more than eight-fold than that of pristine PGS-U. A sustained release for both dugs was observed by 200 h. The slowest and controlled drug release rate was determined in the case of PGSU containing 5 wt% clay and cured at 80 °C. A non-Fickian diffusion can be concluded in the case of tetracycline release via PGS-U/nanoclay bionanocomposites, while a Fickian process was detected in the case of metronidazole release by PGS-U/nanoclay bionanocomposites. As a result, the designed scaffold showed high flexibility, which makes it an appropriate option for utilization in the treatment of periodontal disease.


Subject(s)
Glycerol , Nanocomposites , Clay , Decanoates/chemistry , Drug Delivery Systems , Glycerol/analogs & derivatives , Glycerol/chemistry , Metronidazole , Nanocomposites/chemistry , Polymers , Tetracycline , Urethane
14.
Chemosphere ; 289: 133219, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34902387

ABSTRACT

As a consequence of industrial activities, one of the most prevalent components in wastewater is Water-soluble dyes needed to be removed. In this research, eco-friendly adsorbents based on poly(glycerol sebacate) (PGS), including PGS-graphene oxide nanoparticles (GO), PGS-graft-chitosan(CS), and PGS-CS-GO nanocomposites, have been proposed as efficient dye adsorbents for the wastewater treatment procedure. FESEM images showed that a smooth and uniform structure was created over incorporating CS into PGS. Besides, the presence of CS within PGS/GO nanocomposites had a positive impact on the exfoliation of GO. Moreover, it was found that the incorporation of both CS and GO into PGS reduced the glass transition of PGS. Besides, their coexistence can probably increase the chain regularity in the polymer matrix and cause a relatively larger crystal size of PGS. In this regard, the ternary nanocomposite saw a Tg value of -29.4 °C. A high adsorption capacity of 178 mg g-1, as well as 99 removal% efficiency, were observed in the case of the PGS-CS-GO sample after 300 min at a dye concentration of 100 mg L-1 and pH 7. Additionally, the adsorption capacity value of the adsorbent was preserved around 129 mg g-1 after 7 cycles of adsorption-desorption. The findings revealed that innovatively synthesized PGS-g-CS/GO nanocomposites could efficiently remove methylene blue from water solutions. Hence, they can be used as a powerful and influential dye adsorbent to purify water solutions.


Subject(s)
Chitosan , Graphite , Nanocomposites , Water Pollutants, Chemical , Adsorption , Coloring Agents , Decanoates , Glycerol/analogs & derivatives , Kinetics , Methylene Blue , Polymers , Water Pollutants, Chemical/analysis
15.
J King Saud Univ Sci ; 33(8): 101648, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34690467

ABSTRACT

SARS-CoV2 is a member of human coronaviruses and is the causative agent of the present pandemic COVID-19 virus. In order to control COVID-19, studies on viral structure and mechanism of infectivity and pathogenicity are sorely needed. The spike (S) protein is comprised of S1 & S2 subunits. These spike protein subunits enable viral attachment by binding to the host cell via ACE-2 (angiotensin converting enzyme-2) receptor, thus facilitating the infection. During viral entry, one of the key steps is the cleavage of the S1-S2 spike protein subunits via surface TMPRSS2 (transmembrane protease serine 2) and results in viral infection. Hence, the S-protein is critical for the viral attachment and penetration into the host. The rapid advancement of our knowledge on the structural and functional aspects of the spike protein could lead to development of numerous candidate vaccines against SARS-CoV2. Here the authors discuss about the structure of spike protein and explore its related functions. Our aim is to provide a better understanding that may aid in fighting against CoVID-19 and its treatment.

16.
ACS Appl Mater Interfaces ; 13(6): 7355-7369, 2021 Feb 17.
Article in English | MEDLINE | ID: mdl-33534550

ABSTRACT

Ni-rich high-energy-density lithium ion batteries pose great risks to safety due to internal short circuits and overcharging; they also have poor performance because of cation mixing and disordering problems. For Ni-rich layered cathodes, these factors cause gas evolution, the formation of side products, and life cycle decay. In this study, a new cathode electrolyte interphase (CEI) for Ni2+ self-oxidation is developed. By using a branched oligomer electrode additive, the new CEI is formed and prevents the reduction of Ni3+ to Ni2+ on the surface of Ni-rich layered cathode; this maintains the layered structure and the cation mixing during cycling. In addition, this new CEI ensures the stability of Ni4+ that is formed at 100% state of charge in the crystal lattice at high temperature (660 K); this prevents the rock-salt formation and the over-reduction of Ni4+ to Ni2+. These findings are obtained using in situ X-ray absorption spectroscopy, operando X-ray diffraction, operando gas chromatography-mass spectroscopy, and X-ray photoelectron spectroscopy. Transmission electron microscopy reveals that the new CEI has an elliptical shape on the material surface, which is approximately 100 nm in length and 50 nm in width, and covers selected particle surfaces. After the new CEI was formed on the surface, the Ni2+ self-oxidation gradually affects from the surface to the bulk of the material. It found that the bond energy and bond length of the Ni-O are stabilized, which dramatically inhibit gas evolution. The new CEI is successfully applied in a Ni-rich layered compound, and the 18650- and the punch-type full cells are fabricated. The energy density of the designed cells is up to 300 Wh/kg. Internal short circuit and overcharging safety tests are passed when using the standard regulations of commercial evaluation. This new CEI technology is ready and planned for future applications in electric vehicle and energy storage.

17.
Clin Case Rep ; 8(10): 2040-2045, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33088547

ABSTRACT

IgG4-RD may rarely present as a retroperitoneal fibrosis, mimicking carcinomatosis. Clinicians should consider this disease when encountering an idiopathic peritoneal and retroperitoneal fibrosis with renal involvement and hydronephrosis.

18.
Polymers (Basel) ; 12(5)2020 May 13.
Article in English | MEDLINE | ID: mdl-32414019

ABSTRACT

Low-molecular-weight carbonyl-containing compounds are considered beneficial energy storage materials in alkali metal-ion/alkaline earth metal-ion secondary batteries owing to the ease of their synthesis, low cost, rapid kinetics, and high theoretical energy density. This study aims to prepare a novel carbonyl compound containing a maleamic acid (MA) backbone as a material with carbon black to a new MA anode electrode for a lithium-ion battery. MA was subjected to attenuated total reflection-Fourier-transform infrared spectroscopy, and its morphology was assessed through scanning electron microscopy, followed by differential scanning calorimetry to determine its thermal stability. Thereafter, the electrochemical properties of MA were investigated in coin cells (2032-type) containing Li metal as a reference electrode. The MA anode electrode delivered a high reversible capacity of about 685 mAh g-1 in the first cycle and a higher rate capability than that of the pristine carbon black electrode. Energy bandgap analysis, electrochemical impedance, and X-ray photoelectron spectroscopy revealed that MA significantly reduces cell impedance by reforming its chemical structure into new nitrogen-based highly ionic diffusion compounds. This combination of a new MA anode electrode with MA and carbon black can increase the performance of the lithium-ion battery, and MA majorly outweighs transitional carbon black.

19.
Phytochem Anal ; 31(5): 575-582, 2020 Sep.
Article in English | MEDLINE | ID: mdl-31997419

ABSTRACT

INTRODUCTION: Rosmarinic acid is a bioactive compound with various pharmaceutical effects and applications. OBJECTIVE: This work developed a new approach for aqueous enzymatic extraction of rosmarinic acid from the leaves of Salvia officinalis. METHODS: Different enzymes (proteases and cellulase) were evaluated for their extraction activity. Response surface methodology (RSM) was subsequently employed to optimise the extraction conditions. Thin layer chromatography was also used to identify rosmarinic acid in the extract of S. officinalis. RESULTS: Among the tested enzymes, a Cellulase A and Protamex mixture (1:1, w/w) exhibited maximum effectiveness in the extraction. Through the use of RSM, the maximum rosmarinic acid content of 28.23 ± 0.41 mg/g was obtained with enzyme loading of 4.49%, water-to-sample ratio of 25.76 mL/g, temperature of 54.3°C, and extraction time of 2 h. CONCLUSION: This study suggests that S. officinalis is a promising source of rosmarinic acid and aqueous enzymatic extraction is an efficient and ecofriendly method for extracting rosmarinic acid, with a short extraction time and without the contamination of a toxic solvent.


Subject(s)
Salvia officinalis , Cinnamates , Depsides , Plant Extracts , Plant Leaves , Rosmarinic Acid
20.
Bioresour Technol ; 296: 122334, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31698223

ABSTRACT

Spent coffee grounds (SCGs) are a promising material for sustainable preparation of biodiesel. This study proposed a new approach for biodiesel synthesis from wet SCGs using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as both a green solvent and catalyst. The optimal reaction conditions were determined as a methanol amount of 6.25 mL/g of wet SCGs, DBU amount of 14.46 mL/g of wet SCGs, temperature of 60.2 °C, and reaction time of 28.65 min through response surface methodology. Under these conditions, the maximum biodiesel yield was 97.18%. Notably, DBU polarity could be regulated reversibly, facilitating its reusability and a simple process for product separation. Under optimal conditions, DBU could be potentially reused for at least 10 cycles to yield high amounts of biodiesel. This study suggests that the switchable solvent-assisted direct transesterification of wet SCGs is a potential, efficient, cost-effective, and eco-friendly approach for biodiesel synthesis.


Subject(s)
Biofuels , Coffee , Catalysis , Esterification , Methanol , Solvents
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