Peroxide Scavenging Research Articles

Green synthesized cobalt nanoparticles from Trianthema portulacastrum L. as a novel antimicrobials and antioxidants

Trianthema portulacastrum is a dietary and medicinal plant that has gained substantial importance due to its pharmacological properties. This plant was used for its various healing properties since the ancient period in ayurvedic system of medicine. The green synthesis technique is an eco-friendly as well as cost effective technique which can produce more biocompatible nanoparticles when compared with those fabricated by physio-chemical methods. Therefore, nanoparticles produced by green synthesis are credible alternatives to those which are produced by conventional synthesis techniques. This research mainly aims to produce nanoparticles with the methanolic leaf extract of T. portulacastrum. The optimized nanoparticles were further analyzed for anti-fungal, anti-bacterial and antioxidant properties. Disk diffusion assay was used for the determination of the antimicrobial property and on the other hand, DPPH radical scavenging assay as well as hydrogen peroxide scavenging activity proved the antioxidant property of the formulation. The study revealed that Escherichia coli (gram negative strain) shows greater zone of inhibition when compared with Bacillus subtilis (gram positive bacteria). The nanoparticles have also been reported to show significant anti-fungal activity against the strains of Aspergillus niger and Fusarium oxysporum which proves its desirability for its further use against both bacterial as well as fungal infections. The novel formulation can be explored dually as antimicrobial and antioxidant agent.

Evaluation of Antioxidant, Antimicrobial, and Anticancer Properties of Onion Skin Extracts

Onion skins (OS) are a by-product of onion processing that causes both biological and environmental problems. Thus, OS could be used sustainably and as means of circular economy since they contain valuable bioactive compounds that can be used for the production of high-added-value products. This study aims to evaluate the potential antioxidant, antimicrobial, and anticancer properties of onion OS crude extracts. The extracts were prepared using different solvents (i.e., water, ethanol, and their mixtures) and evaluated for their total phenolic content and phytochemical composition, their antioxidant activity (using the DPPH radical scavenging assay, the ferric reducing antioxidant power (FRAP) assay, and the hydrogen peroxide scavenging assay), anti-inflammatory properties, as well as for their antimicrobial (against Listeria monocytogenes, Escherichia coli O157:H7, Bacillus cereus, Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhimurium, and Yersinia enterocolitica) and anticancer (against human breast cancer cells (MCF-7) and human glioblastoma cells (U-87 MG)) activity. The results revealed that the extracts contained a significant amount of phenolic compounds, ranging between 348.71 and 795.11 mg gallic acid equivalents per g of dry weight. The extracts showed promising cytotoxic effects (up to ~40%) against cancer cell lines, indicating their potential as a natural source of anticancer agents. Additionally, the extracts exhibited strong antioxidant and antimicrobial activity against the tested microorganisms. The findings of this study suggest that OS crude extracts could be a promising candidate for developing natural functional foods and pharmaceuticals. They could be used as natural alternatives for the prevention and treatment of various diseases caused by oxidative stress, microbial infections, or cancer since they are a valuable source of bioactive compounds that can be used for various applications such as food preservation, nutraceuticals, and pharmaceuticals.

Bioactivities of Garcinia kola enzymatic hydrolysates at different enzyme–substrate ratios

Natural products, such as enzymatic hydrolysates and bioactive peptides from dietary sources, are safe alternatives to synthetic compounds linked to various deleterious effects. The purpose of this study is to determine the in vitro bioactivities (antioxidant and anti-inflammatory activities) of Garcinia kola seeds enzymatic hydrolysates (GKPHs) at different enzyme (pepsin)-substrate ratios. G. kola protein, isolated by alkaline solubilization and acid precipitation, was hydrolyzed with pepsin at varying enzyme–substrate (E:S) ratios. The antioxidant parameters investigated include 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging, hydrogen peroxide scavenging and ferrous ion (Fe2+) chelating activities. For anti-inflammatory properties, membrane stabilization and protein denaturation activities tests were used. GKPH produced at 1:32 had the highest degree of hydrolysis (66.27 ± 4.21%). All GKPHs had excellent in vitro anti-inflammatory properties. However, only enzymatic hydrolysates produced at 1:16 (E:S) ratio chelated iron (II) and as well had the highest percentage hemolysis inhibition of 84.45 ± 0.007%, percentage protein denaturation inhibition of 53.36 ± 0.01% at maximum concentration and exhibited highest DPPH scavenging activity (87.24 ± 0.10%). The enzymatic hydrolysates had excellent solubility, emulsifying and foaming properties. It could be deduced from this study that pepsin at a ratio of 1:16 of G. kola protein produced the most effective enzymatic hydrolysates in terms of their antioxidant and anti-inflammatory activities. G. kola pepsin enzymatic hydrolysates, thus, have potential in development as functional foods and as therapeutics pharmaceutical industries in the management of diseases associated with oxidative stress and inflammation owing to their excellent functional, antioxidant and anti-inflammatory properties.

Antioxidant, analgesic, anti-inflammatory, and antipyretic potentialities of leaves of Artabotrys hexapetalus, established by in silico analysis

BackgroundArtabotrys hexapetalus is a rare plant in the Indian subcontinent. This plant is used for different therapeutic purposes in folk medicine and many bioactive compounds are reported in this plant. Considering its traditional uses and the presence of medicinal compounds, we aimed to evaluate some pharmacological properties of its leaves along with in silico analysis in scientific ways. MethodsAntioxidant tests were conducted in both qualitative and quantitative ways. 2,2-Diphenyl-1-picryl hydrazyl (DPPH), hydrogen peroxide, and superoxide radicals scavenging with FeCl3 reducing properties of A. hexapetalus extract were carried out. Acetic acid-induced writhing, tail immersion, formalin-induced paw edema, and Brewer's yeast-induced pyrexia methods were followed to conduct peripheral analgesic, central analgesic, anti-inflammatory, and antipyretic potentialities, respectively. Finally, molecular docking and absorption, distribution, metabolism, excretion, and toxicity (ADMET) analysis of reported compounds were conducted. ResultsThe A. hexapetalus extract was found to possess a quite good amount of phenolics, flavonoids, and tannins. This extract also revealed good radical scavenging effects along with ferric chloride-reducing capabilities. In the analgesic tests, the extract showed excellent responses in writhing inhibition and elongation in tail withdrawal time. The extract also significantly lessened paw edema over time at both doses. A notable decrease in body temperature was also observed. Those responses revealed nice pharmacological potentialities. Along with these findings and conducting in silico analysis, we finally proposed seven molecules as lead compounds. ConclusionOur analysis revealed that A. hexapetalus leaves are highly enriched with antioxidants and the extract showed good pharmacological characteristics.

Antioxidant, antimicrobial, and antibiofilm properties of essential oils extracted from Dialium guineense

ABSTRACT This study aimed to explore the chemical composition and biological properties of Dialium guineense essential oils derived from its fruit and leaf. These oils have significant potential as natural alternatives in industries such as food, pharmaceuticals, and cosmetics. The research involved extraction, characterization, antioxidant, and antimicrobial evaluations. The fruit essential oil contained 30 identified compounds, with hexadecanoic acid as the major component. The leaf essential oil had 44 identified compounds, with falcarinol as the predominant compound. Antioxidant capacity was assessed, resulting in a total antioxidant capacity of 70.4 μg/g AAE for the fruit essential oil and 40 μg/g AAE for the leaf essential oil. In the hydrogen peroxide scavenging assay, the fruit essential oil demonstrated an IC50 value of 347.7 ± 0.5 μg/mL, while the leaf essential oil exhibited an IC50 value of 931.7 ± 0.6 μg/mL. The antimicrobial activity of the essential oils was evaluated against various microorganisms. The fruit essential oil showed significant efficacy against S. aureus, S. pneumoniae, K. pneumoniae, P. aeruginosa, E. coli, and C. albicans. The leaf essential oil displayed effectiveness against S. pneumoniae, E. coli, and E. faecalis. Both essential oils inhibited biofilm formation in P. aeruginosa. Molecular docking analysis revealed that compounds in the leaf essential oil had higher binding affinity for LasR, which correlated with superior anti-biofilm activity. These findings suggest that the essential oils from D. guineense have therapeutic potential in combating various diseases.

Biogenic synthesis, characterization and applications of Tellurium nanoparticles from Chicoreus virgineus (Roding, 1798)

Nanoparticles will offer a better perspective for the biogenic manner of the future. The green material's reducing agents offer a crucial pathway for the synthesis of metal nanoparticles. A biological method was adopted to develop tellurium mediated nanoparticles with the shell of marine gastropod Chicoreus virgineus. 10.7 g of Tellurium tetrachloride was dissolved in 1 L of the double distilled water to prepare 0.01 M Solution.The nanoparticle synthesis was confirmed by UV-Visible spectroscopy, the absorbance values of the nanoparticles generated were identified and the wavelength around 300nm was observed. The presence of reducing agents is indicated by Fourier Transform Infrared Spectroscopy. FTIR analysis showed the peak values from 3336.35 cm-1 to 708.30 cm-1. Images from atomic force microscopy and scanning electron microscopy were used to display the surface morphology. The rod like structure and spherical, uniform shape of tellurium nanoparticles were observed. The particle size of 21.31 nm was recorded for the synthesized nanoparticles. The antibacterial, antifungal, DPPH scavenging, and hydrogen peroxide scavenging assay activity of the produced nanoparticles was tested. The maximum zone of inhibition was observed against the pathogens viz., Propionibacterium acnes (6.5 mm) and Aspergillus fumigatus (16.5 mm). The highest percentage inhibition of 71.4% for DPPH scavenging activityand 92.12% for hydrogen peroxide assay were observed. Theoutcomes demonstrated that this affordable synthesis found many useful biomedical applications. The current investigation is one of the eco-friendly methods of synthesis and it is an easy method for the synthesis of nanoparticles. These nanoparticles act as an effective antibacterial, antifungal and antioxidant agent. Hence it will show a greater scope in the medicinal field. The nanoparticles derived from marine gastropod Chicoreus virgineus has good biocompatibility. Only few studies have been reported earlier using the marine molluscs.

In Vitro Antioxidant, Anti-inflammatory, Antimicrobial, and Antidiabetic Activities of Synthesized Chitosan-loaded p-Coumaric Acid Nanoparticles.

p-Coumaric acid is a phenolic compound widely distributed in fruits and vegetables that displays an array of therapeutic properties, including antidiabetic effects. Prominent application in diabetes is limited due to its suboptimal pharmacokinetics, poor aqueous solubility, and poor bioavailability. Nanotechnology-based delivery methods have been developed to address these limitations and improve the therapeutic uses of p-coumaric acid, and the nanoencapsulation method is emerging as a feasible alternative. The objective of this study is to synthesize p-coumaric acid nanoparticles (PCNPs) and to evaluate their In Vitro activities. The PCNPs were synthesized by the nanoprecipitation method and characterized by UV-visible spectroscopy, zeta potential, Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) with dispersive energy X-ray (EDX) analysis. In addition, the PCNPs were analyzed for In Vitro antioxidant activity using six different free radical scavenging assays and were also analyzed for antimicrobial, anti-inflammatory, antithrombotic, and antidiabetic effects. The formation of PCNPs was confirmed by UV-visible spectra at 283 nm, and FTIR analysis revealed the reduction and capping of the chitosan nanoparticles. SEM was used to assess the size and shape of the PCNPs, and the high absorption property of the PCNPs was investigated using EDX analysis. The PCNPs had significant antioxidant, hydrogen peroxide (H2O2), lipid peroxidation (LPO), superoxide and nitric oxide (NO) radical scavenging power activities, and showed potent antimicrobial, anti-inflammatory, antithrombotic, and antidiabetic activities. The present study suggests that PCNPs can be used as a potential medication delivery approach to provide a greater nephroprotective effect in the treatment of diabetic nephropathy. To the best of our knowledge, this is the first attempt at the synthesis of chitosan-loaded PCNPs.

Antioxidant, Antiviral, and Anti-Inflammatory Activities of Lutein-Enriched Extract of Tetraselmis Species.

Microalgae are proposed to have powerful applications for human health in the pharmaceutical and food industries. Tetraselmis species (sp.), which are green microalgae, were identified as a source of broad-spectrum health-promoting biological activities. However, the bioactivity of these species has not been elucidated. We aimed to confirm the antioxidant, antiviral, and anti-inflammatory effects of Tetraselmis sp. extract (TEE). TEE showed 2,2-diphenyl-1-picryl-hydrazyl-hydrate radical and hydrogen peroxide scavenging activities and reduced plaque formation in Vero E6 cells infected with vaccinia virus. TEE treatment also significantly inhibited nitric oxide (NO) production and improved cell viability in lipopolysaccharide (LPS)-induced RAW264.7 cells. These anti-inflammatory effects were further analyzed in LPS-induced RAW 264.7 cells and the zebrafish model. Further, TEE reduced induced NO synthase expression and proinflammatory cytokine release, including tumor necrosis factor-α, interleukin-6, and interleukin-1β, through MAPKs and NF-κB-dependent mechanisms. Further analysis revealed that TEE increased the survival rate and reduced cell death and NO production in an LPS-stimulated zebrafish model. Further, high-performance liquid chromatography revealed a strong presence of the carotenoid lutein in TEE. Overall, the results suggest that lutein-enriched TEE may be a potent antioxidant, antiviral, and anti-inflammatory agent that could be sustainably utilized in industrial applications.

In Vitro Antioxidant and Fibroblast Migration Activities of Fractions Eluded from Dichloromethane Leaf Extract of Marantodes pumilum.

(1) The complexity of diabetes and diabetic wound healing remains a therapeutic challenge because proper and systematic wound care and management are essential to prevent chronic microbial infection and mechanical damage to the skin. Marantodes pumilum, locally known as 'Kacip Fatimah', is an herb that has been previously reported to possess anti-inflammatory, analgesic, antinociceptive and antipyretic properties. The current study aims to assess the antioxidant and fibroblast cell migration activities of the fractions eluded from the dichloromethane extract of M. pumilum leaves. (2) The total antioxidant capacity of M. pumilum was assessed using the total proanthocyanidins and phosphomolybdenum assays, while DPPH, nitric oxide, hydrogen peroxide and superoxide free radical scavenging assays were tested to determine the antioxidant potential of M. pumilum. An in vitro scratch wound assay was performed to measure the fibroblast cell migration rate using normal and insulin-resistant human dermal fibroblast cells. (3) All M. pumilum fractions exhibited good antioxidant and fibroblast cell migration activity, among which fractions A and E displayed the greatest effect. (4) M. pumilum's fibroblast migration activity could be attributed to its strong antioxidant properties along with its previously reported properties.

Characterization of Polyphenols from Chenopodium botrys after Fractionation with Different Solvents and Study of Their In Vitro Biological Activity.

In the present work, we have investigated the polyphenolic composition of Chenopodium botrys from Bulgaria. The polyphenols were fractionated with solvents of varying polarity (n-hexane, chloroform, ethyl acetate, and n-butanol). The fractions were analyzed by HPLC-PDA and UHPLC-MS. The ethyl acetate fraction contained mono- and di-glycosides of quercetin, di-glycosides of kaempferol, and isorhamnetin and monoglycosides of hispidulin and jaceosidine. We found quercetin triglycosides in the butanol fraction. The ethyl acetate and butanol fractions contained 168.82 mg/g Extr and 67.21 mg/g Extr of quercetin glycosides, respectively. The main components of the polyphenolic complex in C. botrys were 6-methoxyflavones (355.47 mg/g Extr), which were found in the chloroform fraction. The flavonoids pectolinarigenin, demethylnobiletin, and isosinensetin, and the glycosides of quercetin (triglycosides, acylglycosides), kaempferol, isorhamnetin, hispidiulin, and jaceosidine, were discovered and reported in Chenopodium botrys for the first time. We used in vitro methods to assess the biological activity against oxidative stress (hydrogen peroxide scavenging activity (HPSA) and hydroxyl radical scavenging activity (HRSA)), nitrosative stress (nitric oxide scavenging activity (NOSA)), anti-inflammatory activity (IAD inhibition), and anti-tryptic activity (ATA). Quercetin mono- and di-glycosides exhibited greater HPSA and HRSA (IC50 = 39.18, 105.03 µg/mL), while 6-methoxyflavones had a greater NOSA (IC50 = 146.59 µg/mL). The same components showed the highest ATA (IC50 ranging from 116.23 to 202.44 µg/mL).

HPLC-UV-MS/MS Profiling of Phenolics from Euphorbia nicaeensis (All.) Leaf and Stem and Its Antioxidant and Anti-Protein Denaturation Activities

This work focuses on the leaves and stems of Euphorbia nicaeensis All. to confirm its historical use by the Moroccan population. The phytochemical profile of the plant by HPLC-UV-MS/MS was identified for the first time, and the biological activities of each plant organ was evaluated separately by maceration and ultrasonic-assisted extraction. The evaluation of antioxidant activity based on DPPH assay and hydrogen peroxide scavenging assay showed that leaves could be used as a natural source of antioxidants as they provide a potent antioxidant effect (DPPH IC50 = 23.47±0.62 µg/ml), (H2O2 IC50 = 110.27 ± 3.59 µg/ml) compared to stems. These results were proven by HPLC-UV-MS/MS analysis and revealed that E. nicaeensis leaves are richer in phenolic compounds, especially quercetin and derivatives, known for their antioxidant properties. In contrast, the stems could be considered a potential anti-inflammatory agent considering their solid anti-inflammatory activity. The most potent effects were obtained at a concentration of 2 mg/ml, which induced 83.98% and 82.04% inhibition against bovine albumin and egg albumin denaturation, respectively, compared to the control. In addition, the stem phytochemical profile indicated the presence of some compounds with anti-inflammatory effects, such as fargesin and nuciferine. Likewise, the findings showed that ultrasound-assisted extraction was more effective than maceration.

Physicochemical Indexes and Evaluation of Antioxidant, Antihemolytic and Antibacterial Activities of Citrus sinensis and Citrus limon Peel Essential Oils

In this study, the physicochemical indexes, phytochemical screening by thin layer chromatography of essential oils (EOs) obtained from C. limon L. and C. sinensis peels and their antioxidant, antihemolyticand antibacterial activities were investigated. The highest yield (0.71%), density (0.918 ±0.05), refractive index (1.974±0.02), saponification value (186.11±1.13 mg KOH/g) where obtained in C. limon, wherethe highest acid value ( 0.45±0.2mg KOH/g) was for C sinensis. Eight and six spots were identified in C. sisensis and C. limon respectively using thin-layer chromatography (TLC). IC50 for DPPH radical-scavenging activity were 7.04 ±1.03 and 8.39 ± 0.9 µg/mL for C. limon and C. sinensis essential oils, respectively. C. limon EO was also demonstrated better antihemolytic activity by peroxide scavenging, IC50 were 12.76± 0.6 for C. limon and 14.26 ±0.3 µg/mL for C. sinensis essential oils. The C. limon peel EOs showed, also, a higher antibacterial effect on S. aureus and E. coli with 20.5±0.2 and 11.5 ±0.01 mm, respectively. Our data showed that both C. limon and C. sinensis EO were inactive against P. aeruginosa.

Investigation of Anti-hepatocarcinogenic Effects of Senna auriculata Silver Nanoparticle and Evaluation of Their Antioxidant Potential

Plant-based biogenic nanoparticle synthesis has appeared as a feasible alternative to conventional approaches to chemical synthesis. As a result, several environmentally benign methods for the quick production of silver nanoparticles have been published in recent years. The methods employ aqueous extracts of plant components like leaves, bark, and roots. In the present study, silver nanoparticles were synthesized from an aqueous leaf extract of S. auriculata. UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive x-ray analysis (EDAX) were employed to validate the synthesized nanoparticles. The UV analysis showed a peak range between 390-420 nm. FTIR showed the functional groups present in the silver nanoparticles (AgNPs). Moreover, the synthesized AgNPs were tested for their antimicrobial activity against both gram-negative and gram-positive bacterial strains. The antioxidant properties were studied with DPPH, hydrogen peroxide, and nitric oxide scavenging activity assays, and a cytotoxic assay was conducted against the Huh-7 cell line by a MTT study. The results showed that the synthesized silver nanoparticles possessed strong antibacterial, antioxidant, and cytotoxic activities against the Huh-7 cell line, indicating that the silver nanoparticles might be used in the pharmaceutical industry and for novel biological applications.

Physicochemical Properties and Biological Activities of Koseret (Lippia adoensis Hochst. Var. Koseret) Seed and Leaf Oil Extracts.

Lippia adoensis Hoechst var. adoensis (wild variety) and variety koseret (cultivated variety) have been used as traditional medicine, condiments, and endemic to Ethiopia. This study aimed to assess the physicochemical properties and biological activities of oil extracts from seed and leaves of koseret (L. adoensis var. koseret). Soxhlet apparatus was used for oil extraction using hexane as a solvent. The oil quality assessment was based on oil yield, acid value, percent free fatty acid, and peroxide value, while the biological activities were investigated based on antioxidant and antimicrobial activities. The antimicrobial experiment was arranged as 2 x1x4 in a completely randomized factorial design with three replications. The result indicated that significantly higher oil yield (2.25%), acid value (2.66%) and free fatty acid (1.34%) were recorded for seed oil using the solvent extraction method. Leaf oil was recorded to have significantly higher values of DPPH (2,2- diphenyl-1- picrylhydrazyl), ascorbic acid and total carotenoid contents, but a lower value of hydrogen peroxide scavenging activity indicated that leaf oil presented higher antioxidant activity than seed oil in koseret. The koseret leaf oil demonstrated stronger antibacterial activity with a maximum zone of inhibition (14.50±0.21 mm), minimum inhibitory concentration (MIC, 0.25 μg/ml) and corresponding minimum bactericidal concentration (MBC, 0.25 μg/ml) against S. aureus. Furthermore, leaf oil has also presented stronger antifungal activity with a maximum zone of inhibition (14.83 mm), MIC (0.25 μg/ml), and minimum fungicidal concentration (MFC, 0.50 μg/ml) against Aspergillus versicolor. It can be concluded from the results of this study that leaf oil extract has demonstrated better biological activities, including both antioxidant and antimicrobial potentials, than seed oil in koseret.

Biogenic Fabrication of Silver Nanoparticles Using Calotropis procera Flower Extract with Enhanced Biomimetics Attributes.

There have been some reports demonstrating the biogenic synthesis of silver nanoparticles (AgNPs) using Calotropis procera (CP) plant extract; however, detailed in-depth debriefing of the vital synthesis parameter for rapid, facile, efficacious synthesis at varied temperatures with effectual characterization of nanoparticles and biomimetic attribute is lacking. This study presents a comprehensive demarcation of the sustainable fabrication of biogenic C. procera flower extract capped and stabilized silver nanoparticles (CP-AgNPs) synthesis with thorough phytochemical characterization and potential biological application. The results revealed that the successful synthesis of CP-AgNPs was instantaneous with the maximum intensity of the plasmonic peak ~400 nm, while morphological results revealed the cubic shape of nanoparticles. CP-AgNPs were found to present stable, well-dispersed, uniform, high anionic zeta potential, and crystalline nanoparticles with a crystallite size of ~23.8 nm. The FTIR spectra indicated that CP-AgNPs were properly capped by the bioactive of C. procera. Moreover, the synthesized CP-AgNPs exhibited hydrogen peroxide scavenging efficacy. In addition, CP-AgNPs showed antibacterial and antifungal activity against pathogenic bacteria. CP-AgNPs displayed significant in vitro antidiabetic and anti-inflammatory activity. An efficient and convenient approach for synthesizing AgNPs using C. procera flower has been developed with enhanced biomimetic attributes that may be further utilized for water treatment, biosensors, biomedicine, and in allied science.

Synthesis, Characterization, Antimicrobial Properties, and Antioxidant Activities of Silver-N-Heterocyclic Carbene Complexes.

The emergence of antimicrobial resistance has become a major handicap in the fight against bacterial infections, prompting researchers to develop new, more effective, and multimodal alternatives. Silver and its complexes have long been used as antimicrobial agents in medicine because of their lack of resistance to silver, their low potency at low concentrations, and their low toxicity compared to most commonly used antibiotics. N-Heterocyclic carbenes (NHCs) are widely used for coordination of transition metals, mainly in catalytic chemistry. In this study, several N-alkylated benzimidazolium salts 2a-j were synthesized. Then, the N-heterocyclic carbene (NHC) precursor was treated with Ag2O to give silver (I) NHC complexes (3a-j) at room temperature in dichloromethane for 48 h. Ten new silver-NHC complexes were fully characterized by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), elemental analysis, and LC-MSMS (for complexes) techniques. The antibacterial and antioxidant activities of salt 2 and its silver complex 3 were evaluated. All of these complexes were more effective against bacterial strains than comparable ligands. With MIC values ranging from 6.25 to 100 g/ml, the Ag-NHC complex effectively showed strong antibacterial activity. Antioxidant activity was also tested using conventional techniques, such as 2, 2-diphenyl-1-picrylhydrazine (DPPH) and hydrogen peroxide scavenging assays. In DPPH and ABTS experiments, compounds 3a, 3b, 3c, 3e, 3g, and 3i showed significant clearance.

Alginate-Based Oral Delivery Systems to Enhance Protection, Release, and Absorption of Catalase.

Oxidative stress, overproduction of reactive oxygen species (ROS), plays an important role in the development of inflammatory bowel diseases. Catalase has great therapeutic potential by scavenging hydrogen peroxide, one of the ROSs produced in cellular metabolisms. However, in vivo application to scavenge ROS is currently limited especially in oral administrations. Here, we introduced an alginate-based oral drug delivery system that effectively protected catalase from the simulated harsh conditions of the gastrointestinal (GI) tract, released it in the small intestine mimicked condition, and enhanced its absorption via M cells, highly specialized epithelium cells in the small intestine. First of all, catalase was encapsulated in alginate-based microparticles with different amounts of polygalacturonic acid or pectin, which achieved an encapsulation efficiency of more than 90%. It was further shown that catalase was released from alginate-based microparticles in a pH-dependent manner. Results indicated that alginate-polygalacturonic acid microparticles (60 wt % Alg:40 wt % Gal) released 79.5 ± 2.4% of encapsulated catalase at pH 9.1 in 3 h, while they only released 9.2 ± 1.5% of encapsulated catalase at pH 2.0. Even when catalase was encapsulated in microparticles (60 wt % Alg:40 wt % Gal) and exposed to pH 2.0 followed by pH 9.1, it still retained 81.0 ± 11.3% enzyme activity compared to that in microparticles prior to the pH treatment. We then investigated the efficiency of RGD conjugation to catalase on the catalase uptake by M-like cells, the coculturing of human epithelial colorectal adenocarcinoma; Caco-2 cells and B lymphocyte; Raji cells. RGD-catalase protected M-cells more efficiently from the cytotoxicity of H2O2, a typical ROS. RGD conjugation to catalase enhanced the uptake by M-cells with 87.6 ± 0.8% RGD-catalase, whereas 11.5 ± 9.2% of RGD-free catalase passed across M-cells. From the results of protection, release, and absorption of model therapeutic proteins from the harsh pH conditions, alginate-based oral drug delivery systems will have numerous applications for the controlled release of drugs that are easily degradable in the GI tract.

Coffee Fruit Roasting: An Approach To Enhance Yield and Bioactivities of Ethanol Extracts from Coffee Husk

This study aims to investigate the effects of roasting dried coffee cherry on total phenol (TP), tannin, and flavonoid (TF) content and to examine the antioxidant and antimicrobial capacity of a coffee cherry husk-derived ethanol extract. Accordingly, the TP and TF content after different roasting regimens ranged from 9.00 to 123.49 mg GAE/g and 2.69 to 35.34 mg QE/g, respectively. The total tannin content decreased from 42.45 mg TAE/g to 0.27 mg TAE/g by the treatment. The DPPH radical and hydrogen peroxide scavenging capacities extended from 24.68 ± 0.05 to 93.83% and 14.45 to 76.07%, respectively, while the ferric reducing capacity increased from 10.85 to 47.02 mg AAE/g. An extract with increased TP and TF as well as stronger antioxidative activity was found to be produced by mild temperature (150 °C) roasting for 25 min or 180 °C for 10 to 15 min, after which the potency declines. The bacterial inhibition zones also increased from 7.03 to 21.30 mm and from 6.00 to 15.77 mm forE. coli and S. aureus, respectively. This study demonstrated that roasting degrades tannin and enhances the antioxidant and antibacterial properties of ethanol extracts of coffee husk.

Parkin Precipitates on Mitochondria via Aggregation and Autoubiquitination.

The loss of the E3 ligase Parkin, in a familial form of Parkinson's disease, is thought to cause the failure of both the polyubiquitination of abnormal mitochondria and the consequent induction of mitophagy, resulting in abnormal mitochondrial accumulation. However, this has not been confirmed in patient autopsy cases or animal models. More recently, the function of Parkin as a redox molecule that directly scavenges hydrogen peroxide has attracted much attention. To determine the role of Parkin as a redox molecule in the mitochondria, we overexpressed various combinations of Parkin, along with its substrates FAF1, PINK1, and ubiquitin in cell culture systems. Here, we observed that the E3 Parkin monomer was surprisingly not recruited to abnormal mitochondria but self-aggregated with or without self-ubiquitination into the inner and outer membranes, becoming insoluble. Parkin overexpression alone generated aggregates without self-ubiquitination, but it activated autophagy. These results suggest that for damaged mitochondria, the polyubiquitination of Parkin substrates on the mitochondria is not indispensable for mitophagy.

Chemical composition, antioxidant, and antimicrobial activities of P. roxburghii oleoresin essential oils extracted by steam distillation, superheated steam, and supercritical fluid CO2 extraction.

Pinus roxburghii is a rich source of high-quality oleoresin that is composed of resin acids and essential oil (EO). The present research work was planned to study and compare the yield, biological activities, and chemical profiling of P. roxburghii oleoresin EOs extracted through various green extraction methods. Steam distillation (SD), supercritical fluid extraction, and superheated SD (SHSD) at different temperatures (120, 140, and 160°C) were employed to extract EOs from P. roxburghii oleoresin. Antioxidant potential of EOs was determined by total antioxidant content/ferric-reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging activity (DPPH-FRSA), hydrogen peroxide scavenging assays, and percentage inhibition in linoleic acid. Antimicrobial activity of EOs was determined by resazurin microtiter-plate, disc diffusion, and micro-dilution broth susceptibility assays. Gas chromatography-mass spectrometry was used to determine the chemical composition of EOs. It was observed that extraction methods significantly affected the yield, biological activities, and chemical composition of EOs. The maximum yield (19.92%) was found in EO extracted by SHSD at 160°C. EO extracted by SHSD at 120°C showed the highest DPPH-FRSA (63.33%±0.47%), linoleic acid oxidation inhibition (96.55%±1.71%), hydrogen peroxide scavenging activity (59.42%±0.32%), and total antioxidant contents/FRAP (134.49%±1.34mg/L of gallic acid equivalent). The antimicrobial activity results showed that superheated steam-extracted EO of 120°C revealed the highest antifungal and antibacterial activity. It is concluded that SHSD is an alternative and effective technique for the extraction of oleoresins EO that improves the EO yield and biological activities. Further research on optimization and experimental parameters for the extraction of P. roxburghii oleoresin EO by SHSD is required.