Scavenging Effect Research Articles

Curcumin-Encapsulated Co-ZIF-8 for Ulcerative Colitis Therapy: ROS Scavenging and Macrophage Modulation Effects.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by the disruption of the intestinal epithelial barrier. This study described the synthesis and characterization of CCM-Co-ZIF-8, a novel composite material with enzyme-like activities similar to catalase, peroxidase, and superoxide dismutase. CCM-Co-ZIF-8 demonstrated the ability to scavenge reactive oxygen species that play a critical role in UC pathogenesis. In vitro studies using lipopolysaccharide-induced RAW264.7 cells showed that CCM-Co-ZIF-8 exhibited anti-inflammatory activity by promoting the transition of macrophages from an M1 to an M2 phenotype. In vivo experiments using a mouse model of UC demonstrated that CCM-Co-ZIF-8 suppressed the expression of proinflammatory cytokines. These findings suggested that CCM-Co-ZIF-8 might hold promise as a therapeutic strategy for the treatment of UC.

Unraveling the Potential of Saccharum officinarum and Chlorella vulgaris towards 5-Fluorouracil-Induced Nephrotoxicity in Rats.

5-Fluorouracil (5-FU) is often used as a chemotherapeutic agent in treating tumors and is said to have adverse effects, including nephrotoxicity. Therefore, the present study aimed to evaluate the protective effects of Chlorella vulgaris (VL) and Saccharum officinarum L. (SOL) against 5-FU-induced nephrotoxicity in rats through the measurement of renal histology, kidney damage indicators, and antioxidant measures. A total of forty-eight male rats were allotted into six groups: group 1 acted as a control negative group (control), group 2 received 5-FU and worked as a control positive group (FU), group 3 received SOL 15 mL/kg (SOL), group 4 received VL 400 mg/kg (VL), group 5 received 5-FU+SOL (5-FU+SOL), and group 6 received 5-FU+VL (5-FU+VL). After fifteen days, blood and renal tissue specimens were collected for hematological, biochemical, molecular, and histopathological examinations. Findings of the current investigation showed that 5-FU leads to hematological alterations and kidney injury evinced by elevated serum concentrations of uric acid, creatinine, and urea (p < 0.01), and a marked increase in kidney MDA and NO levels with a reduction in kidney CAT, SOD and GSH activities (p < 0.05). Alterations of the histopathological structure of kidney tissue in the FU group were noticed compared to the other groups. 5-FU administration elevated expression levels of TNF-α, lipocalin 2, and KIM1 (p < 0.01) compared to the control ones. 5-FU-induced nephrotoxicity was ameliorated after treatment with SOL and VL via their free radical scavenging, potent antioxidant, and anti-inflammatory effects. In conclusion, our findings demonstrate that the treatment with SOL and VL significantly improved nephrotoxicity induced by 5-FU in rats.

Sulfur/nitrogen co-doped carbon-based copper nanozyme with high peroxidase-like activity for dual-channel paper-based detection of melatonin

Multiple heteroatom doping is one of the effective strategies to tune the structure of carbon supports and enhance the catalytic performance of nanozymes. Herein, the carbon-based copper nanozyme with sulfur/nitrogen co-doping (S/Cu-NC) was synthesized by one-step pyrolysis of Cu-doped ZIF-8 with thiourea encapsulated (Th/Cu@ZIF-8). Benefiting from the synergy of binary heteroatoms and 3D porous structure, the obtained S/Cu-NC had more active sites and exhibited outstanding peroxidase-like activity. Subsequently, a dual-channel (colorimetric/fluorescent) detection method for melatonin was developed by selecting 3,3,5,5-tetramethylbenzidine (TMB) and thiamine as the substrates of S/Cu-NC, which was based on the free radical scavenging effect of melatonin. Furthermore, a simple and portable paper-based device was designed to realize the rapid detection of melatonin through color changes under ultraviolet light and daylight, and the limit of detection were 0.87 μM and 1.42 μM, respectively. This paper-based device was successfully applied to detect melatonin in two kinds of drug samples with satisfactory results.

Harvesting surface (interfacial) energy for tribocatalytic degradation of hazardous dye pollutants using nanostructured materials: A review

AbstractIntroductionTribocatalysis, an emerging cutting‐edge technique that uses frictional mechanical energy to activate the catalytic operation of a reaction or material including nanomaterials has garnered the interest of the research community in recent times.AimThis study aimed to critically review original research works directed toward tribocatalytic degradation of various hazardous dye pollutants. Notably, in this review, various nanomaterials and their composites with outstanding tailored degradation profiles are explored for their tribocatalytic degradation efficiency for various dye pollutants. In addition, the effect of various operating factors that are of importance to engineers, industries, and investors for optimization purposes was pragmatically discussed. Also, the effect of electron trapping and radical scavengers alongside the mechanism of tribocatalytic degradation was empirically analyzed.ResultsFrom this work, it was found that the maximum tribocatalytic degradation efficiency was &gt;80% in most cases at an optimum temperature of 20–40°C, time taken of 0.5‐48 hours, and stirring speed of 500‐1000rmp. It was discovered that magnetic stirring enhances the production of •OH, O2•, and h+ by the nanomaterials that are mechanistically responsible for the degradation of the dye pollutants. Also, it was revealed that expended tribocatalyst can be eluted mostly using H2O and can be reused up to 3–10 times while still sustaining degradation efficiency of &gt;80% in most cases and this suggests the industrial scalability and eco‐friendliness potential of this approach.ConclusionIn the end, challenges and research gaps that can pave the way for method improvement and also serve as future research hotspots for researchers were presented.

Catechin ameliorates hepatocellular damage caused by coadministration of isoniazid and rifampicin

It is well known that phyto-constituents possess hepatoprotective properties. The radical scavenging potential of catechin has received substantial research. The goal of the current study was to assess the beneficial effect of Catechin to safeguard rats from liver damage caused by isoniazid and rifampicin. In this investigation, Wistar rats were employed. Administration of isoniazid (100 mg/kg) with rifampicin (100 mg/kg) for 21 days caused hepatocellular injury. The dosages of catechin used were 25, 50, and 100 mg/kg body weight. Blood was drawn at the end of the study, and biochemical tests were performed to determine the enzyme levels. Restoration of AST, ALT, and ALP was brought about by catechin administration (25, 50, and 100 mg/kg body weight). The administration lead to in a restoration of the SOD and catalase levels. The expression of TNF-α, IL-1β, IL-6, MDA, and nitric oxide decreased. The findings prove that catechin had a significant hepatoprotective impact. The hepatoprotective action of catechin might be mediated by the radical scavenging and cytokine suppressing effects.

Studying the ability of olive leaves nanoparticles to reduce free radicals resulting from the effect of gamma rays on water

This study aims to explore the potential of olive leaves nanoparticles (OLNPs) in scavenging free radicals, particularly 2,2-diphenyl-1- picryl-hydrazyl-hydrate (DPPH), and their capability to mitigate the effects of ionizing radiation. The in vitro assessment of antioxidant activity revealed promising results for OLNPs, exhibiting effective DPPH scavenging within a concentration range of 0.00002 to 0.0001 g/l. Additionally, the natural nanoparticles demonstrated significant antioxidant capacity, suggesting their potential as radical scavengers against free radical-induced damages. Characterization of OLNPs was conducted using UV-Visible absorption spectroscopy, revealing surface Plasmon resonance absorption peaks around 287 nm. Furthermore, atomic force microscopy was employed to determine the morphology and size of the OLNPs, indicating an average diameter of 65 nm.

2-Mercaptoethanesulfonic Acid as an Effective Free-Radical Scavenger in Perfluorosulfonic Acid Membrane-Based Polymer Electrolyte Membrane Fuel Cells

Ceria nanoparticle-based free-radical scavengers for the mitigation of oxidative damage in perfluorosulfonic acid (PFSA)-based polymer electrolyte membrane fuel cells (PEMFCs) suffer from the drawbacks of lowered protonic conductivity and leaching in the acidic environment of a PEMFC. As an alternative to ceria, here we demonstrate that oxidative damage can be mitigated by functionalization of Nafion with 2-Mercaptoethanesulfonic acid (MESA) in different (0.1–1.0 wt%) ratio. The spectroscopic investigation indicated successful functionalization of MESA over the Nafion chain and resulting Nafion-MESA composite membranes displayed improved hydration and swelling behavior, and thermal and mechanical properties. At ≤60 °C (95% relative humidity), the protonic conductivity of composite membranes was higher than/equivalent to that of pristine Nafion membrane; however, at ≥70 °C it was ∼6%–8% lower. At 80 °C, conductivity of Nafion-MESA-0.1 wt%, Nafion-MESA-0.25 wt%, pristine Nafion, and state-of-the-art Nafion-CeO2−1wt% membranes were 1.72 × 10−1, 1.67 × 10−1, 1.8 × 10−1, and 1.6 × 10−1 S∙cm−1, respectively. The fluoride emission rate value for the same membranes were 0.30, 0.17, 1.39, and 0.27 mg∙g−1, respectively, thus indicating that Nafion-MESA membranes can substitute the ceria-based membranes as a chemically stable membrane electrolyte in PEMFCs.

Structural characterization and prebiotic potential of polysaccharides from Polygonatum sibiricum

Polygonatum sibiricum has been widely used due to its excellent biological activities. We prepared a novel polysaccharide from P. sibiricum (PSP) in this study. According a monosaccharide composition analysis, PSP was mainly composed of fructose and glucose with a molar percentage of 93.81:5.12. The main linkage types were identified as α-D-Glcp-1→ and →2-β-D-Fruf-1→. The molecular weight of PSP showed no significant change after simulated salivary and gastrointestinal digestion. However, PSP could be broken down by intestinal bacteria. Our findings revealed that PSP administration increased the abundance of probiotics such as Bifidobacterium. Furthermore, the results showed that gut microbes could utilize PSP to produce short-chain fatty acids including acetic acid, propionic acid, and butyric acid. Also, the PSP fermentation broth displayed an excellent scavenging effect on free radicals, including 2,2-diphenyl-1-picrylhydrazyl radical, superoxide radical, and hydroxyl radical. In summary, this study will help to promote the application of PSP as prebiotics in functional food and the medical industry.

Green synthesis of Curcuma longa-mediated Palladium nanoparticles as antioxidant, antimicrobial, and anticancer agents

The biosynthesis of nanomaterials using plants has become a promising substitute for conventional chemical and physical methods. This study aims to produce Palladium nanoparticles (PdNPs) utilizing Turmeric (Curcuma longa) extract and assess their pharmacological application as antioxidant, antifungal, antibacterial, and anticancer agents. PdNPs were characterized using transmission electron microscopy, field emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared, and ultraviolet–visible spectroscopy. PdNPs showed antioxidant activity using the DPPH assay at all tested concentrations. The percentage of scavenging effect for 130 µg/mL PdNPs was 33 %. PdNPs at the same concentration showed noticeable antifungal and antibacterial activity using the agar well diffusion method against candida species and Escherichia coli within an inhibition range of 17 mm and 20 mm, respectively. Also, PdNPs exhibited significant cytotoxic activity at all tested concentrations using an MTT assay against the MCF-7 breast cancer cell line. MCF-7 cell viability declined to 26.53 % in the treated cells at 130 µg/mL. In conclusion, our findings demonstrate the simplicity and efficiency of synthesizing PdNPs using Curcuma longa extract in an eco-friendly manner and their significant antifungal, antibacterial, and anticancer potential.

Sensitive detection of uric acid based on low-triggering-potential cathodic luminol electrochemiluminescence achieved by ReS2 nanosheets.

The majority of previously reported cathodic electrochemiluminescence (ECL) systems often required very negative potential to be carried out, which hasgreatly limited their applications in the sensing field. Screening high-performance cathodic ECL systems with low triggering potential is a promising way to broaden their applications. In this work, rhenium disulfide nanosheets (ReS2 NS) have been revealed as an efficient co-promoter to realize low-triggering-potential cathodic luminol ECL. One strong cathodic ECL signal appeared at a potential of -0.3V and one anodic ECL peak was obtained at -0.15V under the reverse potential scan, which were caused by electrogenerated reactive oxygen species (ROS) from hydrogen peroxide. The generation of strong luminol ECL at low potential was the result of the electrocatalytic effect of ReS2 NS on the reduction of H2O2. The scavenging effect of uric acid (UA) on the ROS could significantly inhibit the cathodic ECL. As a result, an ECL sensor was proposed, which showed outstanding performance for the detection of UA in the range of 10nM to 0.1mM with a low detection limit of 1.53nM. Moreover, the ECL sensor was successfully applied in the sensitive detection of UA in real samples. This work provides anew avenue to establish a low-potential cathodic ECL system, which will sufficiently expand the potential application of cathodic ECL in the sensing field.

Supplementation species effect on the phenolic content and biological bioactivities of the decocted green tea

Background: Green tea, produced from the leaves of Camellia sinensis, is the most widely consumed beverage in the world after water, and it is widely sold and popular owing to its flavor, and its health benefits. Spices have been used by consumers worldwide to improve flavors of food including tea. Phenolics are the most common phytochemical found in herbal teas and are beneficial in promoting health or preventing diseases. Aims: This study aims to investigate the impact of the addition of mint (Mentha piperita L.), cinnamon (Cinnamomum verum), star anise (Illicium verum), ginger (Zingiber officinale), white mugwort (Artemisia herba alba) and clove (Syzygium aromaticum) on green tea biological properties, and on consumers’ acceptance. Subjects and Methods: Different green tea blends were formulated with 10% of each proposed spice. Total phenolic and flavonoid contents of formulated blends were measured by Folin-Ciocalteu and aluminum chloride methods, respectively. The effect of these herbs supplementation on antioxidant activity of green tea was determined using three different methods, namely DPPH assay, ferric reducing antioxidant power (FRAP), and total antioxidant capacity (TAC). In vitro antibacterial activity was assessed by the disc-diffusion method. Consumers’ acceptance of tea blends was evaluated by a sensory hedonic analysis performed by 127 panelists. Results: The results revealed significant variability among tea blends in terms of both total polyphenols (from 591.951 to 1027.387 mg GAE/L) and flavonoids (from 140.78 to 279.329 mg QE/L). As regards the antioxidant activity, control (no supplemented) green tea exhibited the highest ferric reducing antioxidant power (RC0.5 = 27.25 mg AAE/g DE). Interestingly tea blends supplemented with white mugwort and ginger demonstrated the highest DPPH• scavenging effect with IC50 of about 3.37 and 3.38 mg AAE/g DE, respectively, while when supplemented with star anise, it showed the highest TAC (66.143 mg AAE/g DE). In the assessment of the antibacterial effect, control green tea showed the best efficacy, except for Listeria innocua which was particularly sensitive to samples flavored with star anise and clove. The sensory evaluation revealed that clove-flavored tea was the most preferred by the panelists (31.75%), closely followed by ginger green tea (30.95%), green tea and star anise flavored green tea (25.39%). Conclusion: The obtained results indicate that adding some species to green tea significantly enhance its phenolic content, boost its antioxidant capacity and improve its sensory properties. Keywords: Flavored green tea; polyphenols; antioxidant activity; antibacterial activity; sensory characteristic.

Effect of Curcuma xanthorrhiza Extracts on the Phytochemical Content, Antioxidant Activity and Lactobacillus casei Growth

Curcuma xanthorrhiza (CX) has been reported as the most widely cultivated species in Southeast Asia. It is commonly found in the wild and has been traditionally used for medicinal purposes. The rhizome and root of CX contain constituents that offer various health benefits, including the treatment of skin inflammations and acne, as well as having antioxidant properties. Recently, numerous herbal products and traditional medicines made from CX have appeared in the market, available in forms such as capsules and bottled drinks. However, no research has yet validated the potential of growing Lactobacillus casei (L. casei) probiotic bacteria in CX extracts. The aim of this study is to determine the total phytochemical content of CX extracts, the antioxidant activity of CX extracts, and the prebiotic potential of CX. In this article, the chemical contents of CX, including total phenolics, total flavonoids, and antioxidant activity, have been studied using the Folin-Ciocalteu method, the aluminum chloride colorimetric method, and the DPPH free radical scavenging assay for antioxidant activity. The studies were conducted using three different methods of extracting CX: methanol-maceration, fresh juiced, and fresh boiled CX. The prebiotic potential of CX was studied using the L. casei probiotic strain. From the methanol-maceration extraction, the values of TPC and TFC are 111.55 ± 13.64 μg GAE/mg DW and 27.30 ± 7.75 μg QE/mg DW, respectively. Meanwhile, for the fresh juiced extraction, the TPC and TFC values are 30.513 ± 0.917 μg GAE/mg DW and 43.81 ± 5.13 μg QE/mg DW, respectively. Lastly, the boiled extraction method yields a TPC of 10.85 ± 0.21 μg GAE/mg DW and a TFC of 8.00 ± 0.49 μg QE/mg DW. At a concentration of 2000 μg/mL, the scavenging activity of the fresh juiced extraction reached a plateau of 89.33%. Meanwhile, at the same concentration, the scavenging effects of CX fresh methanol maceration and fresh boiled extraction are 61.39% and 49.81%, respectively. The L. casei strain was shown to be actively growing in CX extracts within the first 24 hours; however, after 24 hours, the growth remained almost constant. This may be due to the limited supply of CX extracts for the growth of the probiotic L. casei strain. Altogether, these results demonstrate that CX is a potential source of valuable bioactive compounds that could be used in medical, pharmaceutical, and food industries.

PROXIMATE, PHYTOCHEMICAL, MINERAL COMPOSITION AND ANTIOXIDANT EFFECTS OF METHANOL EXTRACT OF Persea americana (Avacado pear) SEED

The proximate, phytochemical, mineral, and antioxidant composition of Persea americana seed methanol extract was examined in this work. Standard procedures were used for both proximate, mineral composition and quantitative evaluations. Lipid peroxidation, reducing power, and 2,2-diphenyl-1-picryhydrazyl tests were used to measure the antioxidant activity. Using absorption spectroscopy techniques, antioxidant vitamins A, E, and C as well as enzymes (superoxide dismutase, peroxidase, and catalase) were evaluated. Based on the proximate analysis, the P. americana seeds have higher levels of protein (21.00 ± 0.88 %), fat (25.73 ± 2.01 %), and carbohydrates (32.05 ± 1.21 %), but they have lower levels of moisture (8.98±0.10 %) and ash (3.28±0.16 %). A quantitative phytochemical study found that there were phenols (3.51±0.42 mg/100 g),saponins (0.05±0.38 mg/100 g), alkaloid (0.70±0.37mg/100 g), beta-carotene (32.24±0.55mg/100 g), lycopene (6.84±0.52 mg/100 g), flavonoids (34.14±3.13 mg/100 g), phytate (0.00±0.03 mg/100 g), cardiac glycosides (0.37±0.01 %), total phytosterol (21.25±0.12 mg/100 g), stigmasterol (13.16±0.15 mg/100 g) and campesterol (6.16±0.12 mg/100 g). The mineral composition showed that iron and manganese had the lowest quantities, while potassium, calcium, and magnesium had the highest concentrations. The analyzed samples' potential therapeutic benefits in phytomedicine may be attributed to their respective chemical compositions. Out of all the antioxidant vitamins tested, vitamin E had the highest amount (267.73 ± 0.07 mg/100g), followed by vitamin A (7.60 ± 0.01 mg/100 g) and vitamin C (3.88 ± 0.03 mg/100 g). As extract concentration increased, there was a substantial (p&lt;0.05) rise in the DPPH scavenging effect and suppression of...

Optimization, kinetics, and pathways of pharmaceutical pollutant degradation using solar Fenton technique.

Solar Fenton is an important and extensively used advanced oxidation process (AOP) to degrade pharmaceutical pollutants. The objective of this study was to evaluate the performance of simultaneous degradation of the mixed pollutants (amoxicillin, acetaminophen, and ciprofloxacin) for an aqueous solution using the solar Fenton process. Operating parameters such as pH, iron doses, H2O2 doses, pollutant concentrations, and time were studied. From the experimental results, the ideal conditions were obtained for the removal of mixed pollutants such as pH 3, Fe2+ 0.04mM, H2O2 4mM, the concentration of the mixed pollutants 5mg/L, solar radiation 400 W/m2, and time 10min, respectively. The pseudo-first-order kinetics were utilized to investigate the degradation efficacy of the mixed pollutants. The result of the study indicates that the degradation efficiency was > 99% for the mixed pollutants. A maximum of 63% mineralization was observed, and hydroxyl radical scavenger effects were studied. The best optimal conditions were applied to assess the spiked wastewater (municipal wastewater (MWW) and hospital wastewater (HWW)). The highest elimination rates for AMX, ACET, and CIP were observed as 65%, 89%, and 85% for MWW and 76%, 92%, and 80% for HWW, respectively. The degraded by-products were detected by LC-ESI-MS in the water matrix (aqueous solution and spiked wastewater), and ECOSAR analysis was performed for the transformed products. The study concluded that the solar Fenton technique is promising and effective for the removal of mixed pollutants from the water matrix.

Dynamic bond crosslinked maca polysaccharide hydrogels with reactive oxygen species scavenging and antibacterial effects on infected wound healing

In this study, a polysaccharide fragment with antioxidant and reactive oxygen species (ROS) scavenging activities was extracted from Maca (Lepidium meyenii Walp.) and subjected to structural analyses. The fragment, characterized by the α-D-Glcp-(1 → terminal group of the main chain linked to the →4)-Glcp-(1 → end unit through an O-6 bond and the O-3 bond of 1–3-4Glcp, was modified by introducing dialdehyde structures on its glucose units. It was then crosslinked with N-carboxymethyl chitosan via the Schiff base reaction to create a multifunctional hydrogel with antibacterial and ROS scavenging properties. Polyvinyl alcohol was incorporated to form a double crosslinked gel network, and the addition of silver nanoparticles enhanced its antibacterial efficacy. This gel system can scavenge excess ROS, mitigate wound inflammation, eradicate harmful bacteria, and aid in the restoration of skin microecology. The multifunctional maca polysaccharide hydrogel shows significant potential as a medical dressing for the treatment of infected wounds.

The antioxidant, antidiabetic, and antihyperlipidemic effects of the polyphenolic extract from Salvia blancoana subsp. mesatlantica on induced diabetes in rats

Currently, several studies have demonstrated the benefits of medicinal plants in managing type 2 diabetes. In this work, we evaluated the beneficial effects of the polyphenolic extract (PESB) from Salvia blancoana subsp. mesatlantica in the management of hypercaloric-feeding and small-dose alloxan-brought type 2 diabetes in rats. We analyzed the chemical constituents of the extract, including flavones and flavonols content, to understand its biological action. The antioxidant activities were evaluated by total antioxidant action, scavenging effect of the free radical DPPH, and reducing power. The obtained results showed that the value of TFC was estimated at 31.90 ± 0.34 mgEQ/g in the PESB extract. The total antioxidant capacity was estimated at 593.51 ± 4.09 mg (EAA)/g, the value of DPPH IC50 was 7.3 ± 0.00 μg/mL, and the value of EC50 of reducing power was estimated at 6.43 ± 0.01 μg/mL. In total, 14 phenolic compounds were identified and the naringin was the most dominant (63.19%) while the vanillin was the less recorded (0.10%). Serum glucose decreased significantly (p < 0.05) in rats given PESB (100 mg/kg) after four weeks. Glibenclamide (GLB) and PESB reduced HbA1c and increased plasma insulin in diabetic rats, restoring HOMA-β and HOMA-IR levels to near-normal. Additionally, diabetic rats treated with GLB or PESB showed statistically equivalent results to those of non-diabetic rats regarding hepatic enzymes, renal and lipid markers, as well as cardiovascular indices. The weight loss was significantly lower in diabetic rats receiving a dose of PESB (100 mg/kg), and GLB compared to corresponding untreated diabetic rats (p < 0.01). PESB and GLB showed a prominent protective function in the pancreas, liver, and kidney tissues. This investigation demonstrates the capacity of extracts from leaves of S. blancoana subsp. mesatlantica to manage diabetes mellitus due to their richness in a wide range of bioactive compounds. Therefore, more investigations are required to estimate the safety of the plant use.Graphical

The study on in vitro antioxidant properties, cellular immune activities and mice anti-fatigue effects of Sanghuangporus vanninii mycelium polysaccharides

Sanghuang mycelial polysaccharides (SVMPs) were studied using poplar sanghuang as raw material (sanghuangporus vanninii, SV). The bioactivity of SVMPs was evaluated through in vitro antioxidant and cellular immunity activity assays, and the acute oral toxicity and anti-fatigue ability of SVMPs in mice were determined using mice as an experimental animal model. The results showed that SVMPs have a good scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and 2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS+) radicals, with a slightly weaker reducing power. SVMPs promote, to some extent, the secretion of cytokines Tumor Necrosis Factor-α (TNF-α), Interleukin-1β (IL-1β), and Interleukin-6 (IL-6), and the release of NO from mouse macrophage RAW264.7. In mouse experiments, the mouse tolerance of SVMPs was more greater than 18.2 g/kg BW, which was 2724 times the daily dosage of humans, and it was a non-toxic substance; the high dose group of SVMPs could significantly prolong the swimming time of weight-bearing mice. Thus, the results of this study clearly demonstrate the biological activity of SVMPs and provide a valuable basis for the potential application of SVMPs as antioxidants, immunomodulators, and functional foods.

Rational fusion design inspired by cell-penetrating peptide: SS31/S-14 G Humanin hybrid peptide with amplified multimodal efficacy and bio-permeability for the treatment of Alzheimer's disease

Alzheimer's disease is a neurodegenerative disease induced by multiple interconnected mechanisms. Peptide drug candidates with multi-modal efficacy generated from fusion strategy are suitable for addressing multi-facet pathology. However, clinical translation of peptide drugs is greatly hampered by their low permeability into brain. Herein, a hybrid peptide HNSS is generated by merging two therapeutic peptides (SS31 and S-14 G Humanin (HNG)), using a different approach from the classical shuttle-therapeutic peptide conjugate design. HNSS demonstrated increased bio-permeability, with a 2-fold improvement in brain distribution over HNG, thanks to its structure mimicking the design of signal peptide-derived cell-penetrating peptides. HNSS efficiently alleviated mitochondrial dysfunction through the combined effects of mitochondrial targeting, ROS scavenging and p-STAT3 activation. Meanwhile, HNSS with increased Aβ affinity greatly inhibited Aβ oligomerization/fibrillation, and interrupted Aβ interaction with neuron/microglia by reducing neuronal mitochondrial Aβ deposition and promoting microglial phagocytosis of Aβ. In 3× Tg-AD transgenic mice, HNSS treatment efficiently inhibited brain neuron loss and improved the cognitive performance. This work validates the rational fusion design-based strategy for bio-permeability improvement and efficacy amplification, providing a paradigm for developing therapeutic peptide candidates against neurodegenerative disease.

Computational insights into flame development and emission formation in an ammonia engine with hydrogen-assisted pre-chamber turbulent jet ignition

Ammonia, as a promising green fuel for achieving carbon neutrality and zero-carbon emissions, encounters obstacles in practical engine applications due to its intrinsic combustion properties like low burning velocity and high autoignition temperature. Hydrogen-assisted pre-chamber turbulent jet ignition (TJI) technology has recently demonstrated great potential in extending the lean limits and enhancing the stability of ammonia combustion. As such, this study conducts a comprehensive analysis on the flame development and emission formation processes under the active pre-chamber TJI mode fueled with ammonia and hydrogen using computational fluid dynamics (CFD) modeling integrated with detailed chemical kinetics, particularly focusing on the effects of hydrogen energy ratio and spark timing. It is found that the active ammonia-hydrogen TJI engine is typically characterized by four primary physical processes involving H2 mixture preparation in the pre-chamber, flame kernel formation and development within the pre-chamber, the formation and ejection of hot jet across the orifices, and the turbulent flame initiation and propagation in the main chamber. Hydrogen injection holds a scavenging effect on the residuals in the pre-chamber while forms fuel stratification near the spark plug, enhancing the ignition stability. Besides, the current combustion mode is commonly characterized by two-stage heat release in the main chamber, but exhibits a three-stage heat release as increasing the premixed H2 ratio. The first stage is dominated by a hot jet flame, the second stage is characterized by turbulent flame propagation or autoignition, and the third stage is induced by a secondary jet ejected from the pre-chamber, which becomes more prominent as the H2 ratio increases. Hydrogen blending could not only facilitate the turbulent flame propagation of NH3-air mixture in the main chamber but also enhance the initiation of flame kernel in the pre-chamber, thereby promoting the overall combustion process and potentially improving the thermal efficiency. The N2O emission is produced in two distinct stages, wherein N2O is generated and undergoes conversion during the main combustion phase, while unburned crevice gases mix with burned gases and convert into N2O during the expansion stroke. Increasing the premixed hydrogen ratio leads to an increased in-cylinder temperature, which in turn facilitates a reduction in N2O emissions and mitigates unburned ammonia. Furthermore, optimization of the spark timing is required after implementing the hydrogen addition into the intake manifold to achieve desirable combustion phasing and further improve the thermal efficiency. Finally, a novel combustion concept, denoted as TJI assisted compression ignition mode, is proposed for achieving high thermal efficiency in ammonia engines via adopting high compression ratio and premixed ammonia-hydrogen charge under the TJI strategy.

New HCHO-scavenger for enhancing the HCHO-based adhesive in production environmentally friendly agro-based composites

Recently, green products are essential requirements. This work deals with synthesizing novel formaldehyde-scavenger based on black liquor to enhance the urea-formaldehyde (UF) adhesive for production of eco-friendly bio-composites. These HCHO-scavengers are synthesized from black liquor-based aerogel precursors. The assessment is carried out via estimating the HCHO adsorption capacities versus type of black liquor; as well as its beneficial effect on characterization of UF adhesive (Differential Scanning Calorimetry (DSC)-curing temperature; gel time and adhesive strength). The UF-scavenger system, which provides palm fiber-composite with properties (static bending, internal bond, and free-HCHO) compliance with the standard specifications is optimized. The data evidenced the effective role of black liquor (BL) from alkali pulping RS in presence of borohydride in resulting aerogel precursor of scavenger with higher HCHO-adsorption capacities (∼64 mg/g) than that produced from native aerogels (AG) in absence of BL. The kinetic adsorption is most applicable with the pseudo-second order equation. This observed behavior reflected on reducing the gel time and improved the bond strength of scavenger (Scv)-UF systems. It is interesting to note that all investigated BL-scavengers provide reduction in free HCHO of palm composites (from 30.7 mg/100g to 5–11 mg/g). These values are lower than that obtained from scavengers in absence of BLs (17.4 mg/100g). Based on the value of free-HCHO and mechanical properties, we recommend the scavenger resulted from black liquor of alkali pulping RS in presence of anthraquinone and borohydride (NaOH-AQ-BH) of screened RS as effective scavenger to provided eco-palm-wood composites with MOR, MOE, IB, free-HCHO and thickness swelling ∼ 27 MPa, 0.72 MPa, 7157 MPa, 7 % and 11 %, respectively. According to international standard specifications this type of palm-composite fulfills the grade H-3 and E1 according to environmental specification.