DPPH Assay Research Articles

Distributions of Lanostene-Derived Triterpenoids and Glucan Content in the Fruiting Bodies of the Australian Ganoderma Species.

Lanostene-derived triterpenoids and β-glucans are important metabolites in Ganoderma mushrooms associated with benefits to human health. The medicinal value of the Australian Ganoderma species remains unclear, with no data on triterpenoid distribution or glucan content. In the present study, 22 Australian Ganoderma specimens were analyzed for triterpenoid and glucan contents. Thirty-two triterpenoids were identified in the fruiting bodies of 19 of the specimens. Distinct patterns in triterpenoid distribution between laccate and matte fruiting bodies were observed, leading to the classification of four groups of Ganoderma. Most of the glucans in the Ganoderma fruiting bodies were β-glucans (~99%), with a nominal α-glucan content (~1%). The β-glucan content ranged from 19.5 to 43.5% (w/w). A range of antioxidant activities was observed for methanol extracts using the ABTS (1.8 to 8.4 mg GAE.g-1), DPPH (1.7 to 9.4 mg GAE/g-1) and FRAP (24.7 to 111.6 mmol FeSO4.g-1) assays, with four specimens presenting relatively high radical scavenging and reducing activities. For the first time, we demonstrated that Australian Ganoderma mushrooms contain medicinal triterpenoids, including ganoderic acid A, and we established a link between its distribution and the fruiting body morphology. However, further research is required to isolate diploid clones and determine factors that impact triterpenoid and glucan synthesis in these strains.

Harnessing gold-ion crosslinked polyphenol-mediated hydrogels with enhanced tissue adhesiveness, antioxidation, and antibacterial for advanced wound care

Improperly treated wounds can lead to infection, prolonged healing time, and severe health complications. Therefore, developing advanced wound healing materials with antibacterial properties, biocompatibility, and high adhesiveness is essential to support recovery and minimize risks. In this study, tannic acid-modified gelatin-based hydrogel was developed by crosslinking with gold ions, providing multiple properties to meet the requirements for wound healing. The conjugation of tannic acid (TA) on gelatin provides the hydrogel with antioxidative properties, while its ability to form multiple interactions ensures robust crosslinking and enhanced adhesion ability. Meanwhile, incorporating gold ions (Au3+) strengthens its mechanical properties and adds antibacterial effects. The hydrogel forms rapidly in about 10 seconds, featuring a porous structure and mechanical strength suitable for skin tissue. High tissue adhesion, demonstrated through UTM with an average value of 11.5 kPa, adds to its appeal. The hydrogel illustrated antioxidant capacity through DPPH assay and antibacterial ability against both E. coli and S. aureus, thanks to their inherited properties from TA and Au3+, respectively. The cytocompatibility of hydrogel was also demonstrated through WST-1 assay and live/dead staining, with cell viability for all samples over 82 %. These results underscore the potential of this hydrogel for advanced wound care applications.

Assessing a "Least-Concern" Red List Tree Species from Madagascar Used in Traditional Medicine: Morella spathulata (Myricaceae) Phyto-Compounds and Anti-Inflammatory Properties.

Morella spathulata (Myricaceae family) is a common plant from Madagascar and is present on the IUCN Red List of threatened species classified at the 'least concern' level, used by the local population to treat numerous illnesses and pain. Despite its frequent use, comprehensive phytochemical and pharmacological research on the species is limited. This study evaluated the antioxidant, analgesic, and anti-inflammatory properties, as well as the toxicity of methanol extracts from the leaves (MS_L) and bark (MS_B) of M. spathulata. The research involved the analysis of nutritional traits such as sugars, organic acids, vitamin C, polyphenolic content (TPC) and the main phytochemicals by HPLC analysis. Antioxidant capacity was assessed through DPPH and FRAP assays. Analgesic and anti-inflammatory activities were evaluated using acetic acid-induced writhing and carrageenan-induced paw oedema tests in mice. The results showed a high content of phenolic and bioactive components in the leaf and bark extracts, associated with antioxidant, analgesic and anti-inflammatory properties. The interaction of key compounds such as ferulic acid and ellagic acid with proteins involved in pH regulation and immune modulation provides clues to the mechanisms underlying the therapeutic effects. However, conservation efforts are crucial due to habitat loss and illegal logging, and further studies are needed to fully explore the plant's therapeutic potential.

Chemical Composition, Antioxidant, Antibacterial, and Hemolytic Properties of Ylang-Ylang (Cananga odorata) Essential Oil: Potential Therapeutic Applications in Dermatology

Background/Objectives: This study investigates the chemical composition, antioxidant, antibacterial, and hemolytic properties of ylang-ylang (Cananga odorata) essential oil, with a focus on its potential therapeutic applications for dermatological diseases and the importance of transforming such bioactive properties into a stable, safe, and effective formulation. Methods/Rsults: Essential oils were extracted from flowers harvested in northern Grande Comore using hydro distillation at three different distillation times to examine the impact on yield and quality. Gas chromatographic analysis identified a complex mixture of compounds, including linalool, geranyl acetate, and benzyl benzoate. Antioxidant activity was assessed using DPPH, FRAP, TAC, and beta-carotene bleaching inhibition assays, revealing significant radical scavenging capabilities, with DPPH IC50 varying between 1.57 and 3.5 mg/mL. Antibacterial activity was tested against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa, showing promising inhibition zones and minimum inhibitory concentrations. Hemolytic tests indicated varying degrees of red blood cell damage, emphasizing the need for careful concentration management in therapeutic applications. Molecular docking studies highlighted potential therapeutic targets for dermatological conditions, identifying high binding affinities for specific compounds against proteins involved in acne, eczema, and psoriasis. Conclusions: This comprehensive analysis underscores the potential of ylang-ylang essential oil (YEOs) as a natural alternative for antimicrobial treatments and dermatological applications, with its success dependent on optimized extraction methods and precise formulation to reduce cytotoxic effects. A formulation approach is crucial to ensure controlled release, improve bioavailability, and minimize skin irritation.

Anti-Oxidant and Anti-Cancerous Properties of Pyrus pashia (Buch. -Ham.Ex D.Don) Against KB-3-1 Cancer Cell Lines In Vitro

Background: Oral cancer is the fastest-growing cancer in men. Many medicinal approaches are tried step-wise for cancers. Homeopathy and Ayurveda are contributing much to cure cancers without side effects. Plants having antioxidant properties are now being utilized with different solvents to extract different chemical compounds to cure cancer. Objective: The current study aimed to examine the anti-cancer and antioxidant properties of acetone extract of Pyrus pashia (PP-AE) fruit against KB-3-1 cancer cell lines. Materials and Methods: The extract's total phenolic content was determined using a folin-ciocalteu reagent. The DPPH, ABTS, and H2O2 assay were used to measure the free radical scavenging activity of the PP-AE. The MTT assay was used to evaluate the cytotoxic efficacy of the PP-AE against KB-3-1 cancer cell lines at various concentrations. Results: Based on the observations, the total phenolic content was present in the PP-AE of fruit and all free radical scavenging assays have shown remarkable IC50 values. Conclusion: According to the current study, acetone extract of Pyrus pashia fruit significantly possesses antioxidant and anti-cancer properties against oral (KB-3-1) cancer cell lines. This effect may be used in the future to analyze particular chemical compounds in extract, capable of minimizing the growth of oral cancer cells.

Discovery of novel substituted (Z)-N′-hydroxy-3-(3-phenylureido)benzimidamide derivatives as multifunctional molecules targeting pathological hallmarks of Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder marked by significant loss of central cholinergic neurons. This progressive deterioration leads to cognitive dysfunction and impaired motor activity, culminating in the brain cell's death at the later stages of the disease. The approved drugs for AD are limited to providing symptomatic relief for an initial period due to the multifaceted etiology of the disease. Several studies have demonstrated that rivastigmine (RIV) is a selectively potent inhibitor of butyrylcholinesterase and devoid of antioxidant, Aβ, and tau protein aggregation inhibition and anti-inflammatory properties. Therefore, to address these issues associated with RIV, novel rivastigmine-based molecules were rationally designed, synthesized, and evaluated in various in-vitro and in-vivo AD models. In in-vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition studies revealed that 3q &6e as promising leads (AChE, IC50 1.72 ± 0.15, 0.91 ± 0.016 μM, BChE, IC50 6.69 ± 0.28 μM, 1.19 ± 0.026 μM, for 3q &6e, respectively). The computational studies (molecular docking and dynamics) further corroborated the in-vitro studies. Further, 3q and 6e were found to be potent antioxidants in the DPPH assay (IC50 16.15 ± 1.05 & 15.17 ± 0.07 μM, for 3q &6e, respectively). Interestingly, 3q, and 6e could effectively inhibit self-induced full-length tau and Aβ1-42 aggregation. Treatment with 3q &6e inhibited microglial activation by attenuating ROS release and mitochondrial damage. Further, 3q &6e also suppressed NLRP3 inflammasome and NF-κB expression levels in microglial cells and halted the release of pro-inflammatory cytokines in human microglial cells. Finally, 3q &6e were found to be efficacious in reversing the scopolamine-induced memory impairment in the Morris water maze test. The expression of various neuroprotection markers, such as BDNF and TRKB, was significantly overexpressed compared to the disease control group.

Anti-Aging Activities and LC-MS Analysis of Chrysophyllum cainito Leaves Extract

Star apple (Chrysophyllum cainito L.), or Apple-nam in Thai, is a medium-sized tree in the Sapotaceae family. It is native to Middle America and distributed in Thailand and Southeast Asia. It has antioxidation, anti-inflammatory and anti-diabetic properties. The active compounds in star apples are flavonoids. This research aimed to study the biological activities and chemical constituents of crude extract and active fractions from the leaves of star apples. The leaf powder was defatted with dichloromethane and further extracted with ethanol using ultrasound-assisted extraction. The ethanol extract was separated by quick column chromatography given 7 fractions (CCE1-CCE7). The total phenolic content and antioxidant activity of the extract and chromatographic fractions were determined. The active fractions were further studied for tyrosinase inhibition, collagenase inhibition and cell proliferation properties. The result showed that the highest total phenolic content was observed in ethanol extract. The high polar fraction, CCE6, displayed the highest antioxidation activity with radical scavenging of 0.34 ± 0.01 mg AAE/mL in the DPPH assay and a FRAP value of 1.36 ± 0.01 mg AAE/mL in the FRAP assay. The CCE6 also exhibited the highest anti-tyrosinase and anti-collagenase activities with a percentage of 67.14 ± 1.34 and 70.32 ± 2.88, respectively and showed the best activity in cell proliferation with a percentage of 24.68 ± 2.94. The analysis of the components using the negative ionization LC-MS technique revealed that gallic acid and quercetin-3-galactoside are the major constituents in the ethanol extract. While the fraction CCE6 showed glucosyl (2E,6E,10x)-10,11-dihydroxy-2,6-farnesadienoate and p-mentha-1,3,5,8-tetraene as the predominant compounds. HIGHLIGHTS The ethanol extract was prepared using ultrasound-assisted extraction. The first report of tyrosinase and collagenase inhibition, as well as cell proliferation properties, of the cainito leaves extract and chromatographic fractions. The major components of the ethanol extract of cainito leaves in Thailand and its active fraction by LC-MS technique were reported for the first time. GRAPHICAL ABSTRACT

Nanotherapy for Cancer and Biological Activities of Green Synthesized AgNPs Using Aqueous Saussurea costus Leaves and Roots Extracts.

Background/Objectives: Nanoparticles derived from medicinal plants are gaining attention for their diverse biological activities and potential therapeutic applications. Methods: This study explored the antioxidant, anti-inflammatory, anti-tumoral, and antimicrobial properties of green synthesized silver nanoparticles (AgNPs) using the aqueous leaf and root extracts of Saussurea costus (S. costus). The physicochemical characterizations of both biosynthesized AgNPs using the aqueous leaf extract (L-AgNPs) and root extract (R-AgNPs) were examined using UV spectroscopy, fluorescence spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, dynamic light scattering, and Fourier-transform infrared spectroscopy. The antioxidant activity measured using ABTS, DPPH, and FRAP assays showed that AgNPs, particularly from roots, had higher activity than aqueous extracts, attributed to phenolic compounds acting as capping and antioxidant agents. Results: Enzyme inhibition studies indicated that AgNPs exhibited remarkable anti-inflammatory effects, inhibiting COX-1, 5-LOX, and secreted PLA2 enzymes by over 99% at 120 µg/mL, comparable to standard drugs. The anti-tumoral effects were evaluated on the human cancer cell lines HCT-116, LoVo, and MDA-MB-231, with AgNPs inhibiting cell proliferation dose-dependently and IC50 values between 42 and 60 µg/mL, demonstrating greater potency than extracts. The AgNPs also showed enhanced antimicrobial activities against various microbial strains, with IC50 values as low as 14 µg/mL, which could be linked to nanoparticle interactions with microbial cell membranes, causing structural damage and cell death. Conclusions: These findings suggest that S. costus-derived AgNPs are promising natural, biodegradable agents for various biological applications and potential new therapeutic agents, necessitating further research to explore their mechanisms and applications.

Anticholinesterase, Antioxidative and Neuroprotective Effects of Hydroethanolic Extracts of Guiera Senegalensis J. F. Gmel. Leaves on Scopolamine Induced Alzheimer’s Disease in Wistar Rat Models

Background: Medicinal plants like Guiera senegalensis J. F. Gmel. (GS) have gained attention for their potential neuroprotective effects due to their rich composition of bioactive compounds, including flavonoids and polyphenolic acids. While previous studies have highlighted the antioxidant, anti-inflammatory, and neuroplasticity-enhancing properties of GS extract, its efficacy in mitigating dementia-related pathology remains to be fully understood. Objectives: This study aimed to investigate the neuroprotective effects of hydroethanolic GS extract against scopolamine (Sco)-induced dementia in Wistar rats, focusing on its impact on cholinergic function, oxidative stress, neuroinflammation, neurodegeneration, and memory impairment. Methods: Fresh leaves were processed for extraction using standard methods. Antioxidant activity was evaluated using FRAP and DPPH assays. Adult male Wistar rats were used for behavioral tests (Y-maze, NOR, MWM) and biochemical analyses, including ELISA for cholinergic activity, oxidative stress markers (Aβ1-42, phosphorylated Tau), pro-inflammatory cytokines (IL-1β, TNF-α, IL-6, IFN-γ), GFAP, BDNF, and IL-10. Brain tissues underwent histopathological examination. Data were analyzed using GraphPad Prism software. Results: The study assessed the antioxidant potential of GS extract and found that it significantly scavenged DPPH radicals (70.29%) and reduced Fe3+ (49.69%). Behavioral tests showed that GS extract (100 - 400 mg/kg) improved spatial memory and learning in Sco-treated rats. Y-maze results indicated increased spontaneous alternation with GS extract (P < 0.01). NOR and MWM tests showed improved memory and learning, with GS extract-treated rats spending more time in the target quadrant. Biochemical analysis revealed that GS extract increased acetylcholine (ACh), Superoxide Dismutase (SOD), Catalase (CAT), Glutathione (GSH), IL-10, and BDNF levels, while decreasing acetylcholinesterase (AChE), malondialdehyde (MDA), nitrite, Aβ1-42, phosphorylated Tau, IL-1β, TNF-α, IL-6, IFN-γ, and GFAP levels in the hippocampus. Histological analysis confirmed restored hippocampal tissue architecture in AD rats treated with GS extract. Conclusions: Our findings suggest that GS modulates cholinergic, antioxidant, anti-inflammatory, and neuroplasticity pathways, exerting beneficial effects on cognitive functions and biochemical markers associated with Alzheimer's disease (AD) pathology. These results indicate the potential of GS as a neuroprotective agent for the treatment of AD.

Synergistic Effect of Arbuscular Mycorrhizal Fungi and Germanium on the Growth, Nutritional Quality, and Health-Promoting Activities of Spinacia oleracea L.

Arbuscular mycorrhizal fungi (AMF) and the antioxidant germanium (Ge) are promising tools for boosting bioactive compound synthesis and producing healthier foods. However, their combined effect remains unexplored. This study demonstrates the synergistic impact of AMF and Ge on the growth, metabolite accumulation, biological activities, and nutritional qualities of Spinacia oleracea L. (spinach), a globally significant leafy vegetable. Individually, Ge and AMF increased biomass by 68.1% and 22.7%, respectively, while their combined effect led to an 86.3% increase. AMF and Ge also improved proximate composition, with AMF-Ge interaction enhancing crude fiber and mineral content (p < 0.05). Interestingly, AMF enhanced photosynthesis-related parameters (e.g., total chlorophyll) in Ge treated plants, which in turn increased carbohydrate accumulation. This accumulation could provide a route for the biosynthesis of amino acids, organic acids, and fatty acids, as evidenced by increased essential amino acid and organic acid levels. Consistently, the activity of key enzymes involved in amino acids biosynthesis (e.g., glutamine synthase (GS), methionine biosynthase (MS), lysine biosynthase (LS)) showed significant increments. Furthermore, AMF improved fatty acid levels, particularly unsaturated fatty acids in Ge-treated plants compared to the control. In addition, increased phenylalanine provided a precursor for the production of antioxidants (e.g., phenols and flavonoids), through the action of the enzyme phenylalanine ammonia-lyase (PAL), resulting in improved antioxidant activity gains as indicated by FRAP, ABTS, and DPPH assays. This study is the first to show that Ge enhances the beneficial effect of AMF on spinach, improving growth and nutritional quality, with promising implications for agricultural practices.

Exploring the Antimalarial Potential of Entandrophragma Utile and Melochia Umbellata Extracts.

Resistance remains the fundamental problem with antiplasmodial treatments. The study investigated the antiplasmodial, cytotoxic, and antioxidant properties of two Cameroonian medicinal plants, Entandrophragma utile and Melochia umbellata. Antimalarial activity against Plasmodium falciparum strains 3D7 and Dd2 was assessed using the SYBR Green I assay. Cytotoxicity was assessed against Raw and Vero cells using the resazurin assay, and against red blood cells using a hemoglobin release quantification assay. Antioxidant potential was determined using DPPH (2, 2-diphenyl-1-picrylhydrazine), ABTS (2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), and FRAP (ferric-reducing antioxidant power) assays. The most bioactive extract was further analyzed using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS) to determine its phytochemical composition. Extracts from E. utile exhibited moderate anti-malarial activity against Plasmodium falciparum (IC50 =32.81-100 μg/mL), while M. umbellata leaf extract (MULAE) showed strong activity (IC50 =11.62 and 11.91 μg/mL). All extracts demonstrated antioxidant activity (9.22 to 135.8 μg/mL), were selective for Raw and Vero cells, and were not toxic to red blood cells. UHPLC-MS analysis annotated potential pyrimidones, phenolic compounds, and terpenoids in MULAE. MULAE exhibited better antiplasmodial activity, suggesting the presence of unique bioactive compounds. Further research, including in vivo investigations, is needed to develop safe and effective antiplasmodial therapies.

Comparison of Essential Oils of Schinus molle L. Leaves Growing in Different Regions of Algeria in Terms of Their Chemical Compositions and Various Biological Activities

ABSTRACTThis preliminary study investigated the chemical composition and biological properties of essential oils derived from Schinus molle L. leaves obtained from three specific regions in Algeria: Algiers (SMA), Djelfa (SMD), and Mascara (SMM). Gas chromatography (GC) and Gas chromatography–Mass Spectrometry (GC–MS) analyses confirmed the presence of 52 compounds (100.0%) in SMA essential oil, 50 compounds (100.0%) in SMD, and 72 compounds (100.0%) in SMM essential oils. The main components of SMA oil were camphene (31.82%), limonene (14.71%), and p‐cymene (9.25%). In SMD and SMM oils, α‐phellandrene (14.25% and 12.70%), limonene (13.02% and 11.90%), and germacrene D (10.62% and 10.15%) were the major components, respectively. The antioxidant characteristics were evaluated using five methods: β‐carotene‐linoleic acid, DPPH, ABTS+, CUPRAC, and Metal chelating assays. The results revealed a moderate to low anti‐oxidant effect, with SMA essential oils exhibiting the highest activity. A moderate inhibitory effect against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α‐glucosidase, α‐amylase, urease, and tyrosinase was observed, indicating anti‐enzymatic activity. Nevertheless, all samples had higher IC50 values for both antioxidant and anti‐enzymatic activities than 200 μg/mL. It was determined that regional differences in the locations where S. molle grows showed both qualitative and quantitative differences in essential oil components. This difference was also detected in the biological activities of the essential oils. The anti‐inflammatory capacities of the three samples were assessed using Human Red Blood Cell (HRBC) membrane stabilisation and egg albumin denaturation techniques. The results showed effective anti‐inflammatory activity in all three samples. The antimicrobial efficacy was evaluated using a range of tests, such as anti‐quorum sensing, violacein inhibition, anti‐swimming, and anti‐swarming assays, demonstrating moderate activity. No toxic effects were observed at the tested dosages when assessing cytotoxicity against a healthy cell line (CCD18‐Co). This thorough examination provides valuable insights into the chemical composition and bioactive properties of essential oils derived from S. molle. These findings indicate the possible use of these essential oils in the food, medicinal, and cosmetic industries.

Unlocking the Potential of Origanum grosii Essential Oils: A Deep Dive into Volatile Compounds, Antioxidant, Antibacterial, and Anti-Enzymatic Properties within Silico Insights.

The current study's goals were to thoroughly characterize the volatile compounds from Origanum grosii's aerial parts and assess their potential as antioxidants and enzyme inhibitors both in vitro and in silico. The volatile substances in essential oils were identified using GC-MS analysis. Indeed, Origanum grosii essential oil (OGEO) contained carvacrol (15.59%), prehnitol (14.83%), β-Terpinene (13.56%), and thymol (10.36%). The antioxidant potential was assessed using three different assays. Remarkably, OGEO exhibited important antioxidant activity; the IC50 values found were 55.40 ± 2.23, 81.65 ± 3.26, and 98.04 ± 3.87 µg/mL for DPPH, ABTS, and FRAP assays, respectively.The inhibitory effect of essential oils has been studied against enzymes involved in the appearance of human pathologies, including α-glucosidase, α-amylase, tyrosinase, and acetylcholinesterase. In silico, the main compounds in this essential oil demonstrated high binding energies during their associations with the enzymes tested. To sum up, OGEO possesses the ability to function as a natural agent, offering promising qualities suitable for use in food, medicine, and cosmetics.

Production and Quality Evaluation of Yogurt and Watermelon Juice Blends

The study investigated the effect of incorporation of watermelon juice in yogurt on the quality of the blends. Yogurt and watermelon (Citrullus lanatus) juice were produced. The watermelon juice was used to substitute 0, 10, 20, 30, 40, and 50% of yogurt. The chemical composition, antioxidant activity, physicochemical, and sensory properties of the blends were determined using standard procedures. The pH of the yogurt and watermelon juice were 4.57 and 5.78, respectively and varied from 5.18 -6.04 for the blends. The moisture, protein, ash, fat and carbohydrate contents decreased with increase in the amount of watermelon juice in the blends. The vitamin C, calcium, zinc and magnesium contents increased while the phosphorus and potassium contents decreased with increased level of watermelon juice in the blends. The phenols and carotenoids contents increased while the flavonoids content decreased with increase in the level of watermelon juice in the blends. The antioxidant activity using DPPH assay varied with the samples where yogurt had higher radical scavenging activity than the watermelon juice. The radical scavenging activities and the ferric reducing antioxidant property (FRAP) values also increased with the level of watermelon juice in the blends. The FRAP values for yogurt and watermelon juice were 1.22 and 1.58mg/ml, respectively and increased to a range of 1.29 -3.70 mg/ml for the blends. The yogurt had higher scores than the watermelon juice for all the sensory attributes evaluated. The scores for the sensory attributes decreased with increase in the level of watermelon juice in the blends. However, the scores for the blend containing 10 % watermelon juice for all the attributes were not significantly different (p&gt;0.05) from those of the yogurt. Therefore, it is concluded that watermelon juice could be used to substitute 10% yogurt without adversely affecting the qualities of the blends.

Exploring the antimicrobial and antioxidant potential of CuO doped NiO nanocomposites: synthesis, characterization, and melamine sensing evaluation

This research focused on synthesizing CuO@NiO nanocomposites using a co-precipitation method to explore their antimicrobial, antioxidant, and melamine-sensing capabilities. Nickel oxide (NiO), known for its stability and optical properties, was doped with copper oxide (CuO) to enhance its performance. The synthesized nanocomposites showed strong antioxidant activity, achieving 72% inhibition for 2% CuO@NiO and 80% inhibition for 5% CuO@NiO, as determined by the DPPH assay. Antimicrobial tests demonstrated significant inhibition of both Gram-positive and Gram-negative bacteria, particularly with the 5% CuO@NiO composite. Electrochemical analysis, including cyclic voltammetry and differential pulse voltammetry, revealed high sensitivity for melamine detection, with a detection limit of 0.01 µM. These results suggest that CuO@NiO nanocomposites hold promise for applications in antioxidant therapies, antimicrobial treatments, and chemical sensing.

Microwave-assisted synthesis of copper oxide nanoparticles using an Andrographis paniculata leaf extract: Characterization and multifunctional biological activities

This research delves into the environmentally friendly production of copper nanoparticles (CuNPs) using Andrographis paniculata leaf extract (Ap-CuNPs) and their thorough assessment for possible biological purposes. CuNPs were synthesised through a microwave-assisted method using Andrographis paniculata leaf extract. Characterization techniques included ultraviolet spectroscopy (UVVis), FT-IR spectroscopy, SEM, EDAX, XRD, particle size analysis, and zeta potential measurement. Biological activities were assessed through antioxidant (DPPH and H2O2 assays), anti-inflammatory (BSA and egg albumin denaturation assays), antimicrobial, cytotoxic (brine shrimp lethality and MTT assays), and wound healing (scratch assay) tests. Characterization confirmed the formation of Ap-CuNPs with a plasmon resonance peak at 550 nm, the presence of phytochemical capping agents, and high crystallinity. The average particle size was 69.1 nm, with a zeta potential of −12.1 mV. Ap-CuNPs exhibited significant antioxidant activity, with 88.62 % inhibition in the DPPH assay, in the H2O2 assay, which assesses the capacity to scavenge hydrogen peroxide, the Ap-CuNPs achieved 86.3 % inhibition at the same concentration. and anti-inflammatory activity, with 80 % inhibition in the BSA assay. Antimicrobial tests revealed strong activity against gram-negative bacteria in the 22 mm inhibition zone for Pseudomonas sp., for S. aureus, the inhibition zones were 9 mm. Cytotoxicity assessments revealed minimal effects at low concentrations, with 200 μg/ml identified as the optimal dose for wound healing. In vitro wound scratch assays demonstrated enhanced fibroblast migration and wound closure at this concentration.

Antibacterial and Antioxidant Activities of Flavonoids, Phenolic and Flavonoid Glycosides from Gouania longispicata Leaves

The leaves of Gouania longispicata Engl. (GLE) have been traditionally used to treat more than forty ailments in Uganda, including stomachache, lung and skin cancers, syphilis, toothache, and allergies. In this study, pure compounds were isolated from the methanolic extract of GLE leaves and their structures elucidated using ultraviolet visible spectroscopy, liquid chromatography–tandem mass spectrometry, high performance liquid chromatography, and 1D and 2D NMR techniques. The antibacterial and antioxidant activities of the compounds were assessed using the broth dilution and DPPH assays, respectively. Two known flavonoid glycosides (kaempferol-3-O-α-rhamnopyranoside and rutin), a phenolic glycoside (4,6-dihydroxy-3-methylacetophenone-2-O-β-D-glucopyranoside), and flavonoids (kaempferol and quercetin) were characterized. This is the first time that the kaempferol derivative, the acetophenone as well as free forms of quercetin, kaempferol, and rutin, are being reported in GLE and the Gouania genus. The compounds exhibited antibacterial activity against Streptococcus pneumoniae and Escherichia coli with minimum inhibitory concentrations between 16 µg/mL and 125 µg/mL. The radical scavenging activities recorded half-minimum inhibitory concentrations (IC50) ranging from 18.6 ± 1.30 µg/mL to 28.1 ± 0.09 µg/mL. The IC50 of kaempferol and quercetin were not significantly different from that of ascorbic acid (p &gt; 0.05), highlighting their potential as natural antioxidant agents. These results lend credence to the use of GLE leaves in herbal treatment of microbial infections and oxidative stress-mediated ailments.

Characterization, biological activity and photodegradation efficacy of synthesized tryptophan capped silver nanoparticles

Tryptophan capped Silver nanoparticles (AgNPs) were synthesized through a sonochemical method, utilizing tryptophan as a biocompatible and non-toxic capping agent. Based on UV–visible spectra, the optical band gap of the nanoparticles was found to be roughly 3.01 eV. The TEM and XRD measurements of the particle sizes showed a range of 10–22 nm. Under sun irradiation, these nanoparticles showed notable photocatalytic activity, destroying Methylene Blue (MB) dye by more than 79.4 %. With a pseudo-first-order apparent rate constant of 1.5×10−2min-1, the degradation kinetics were observed. The photocatalysis of MB dye was investigated using liquid chromatography in conjunction with electrospray ionization time-of-flight mass spectrometry (LC-ESI-TOF-MS) to determine the products generated and to clarify the degradation processes. Additionally, the antibacterial, anticancer potential showed thate the nanoparticles exhibited good antibacterial and notable anticancer properties. Furthermore, the antidiabetic activity was investigated through α-glucosidase inhibition, demonstrating a significant inhibition rate of 53.98 %. Antioxidant capabilities were also tested using ABTS and DPPH assays, revealing antioxidant activities of 73.9 % and 52.04 %, respectively. Overall, the synthesized tryptophan-capped AgNPs show promising applications in environmental remediation, as well as potential therapeutic uses.

A New Validated Method for Rapid Determination of OLEU Concentration in Dietary Supplements: Comparison with Total Phenol Content and Antioxidant Activity

The market for olive leaf dietary supplements is expanding rapidly and is valued at $437.15 million today. However, information on the control of these products is sketchy and the origin and variety of olives are rarely stated. The aim of this research was to validate a simple and rapid screening method for oleuropein determination in olive leaf dietary supplements. A matrix blank was prepared by removal of oleuropein from a mixture of dietary supplements and the matrix was then spiked with known concentrations to create a spiked matrix calibration curve in the range 5 - 40% oleuropein. Five replicate extractions and analyses of the matrix standards were carried out over 10 days. Precision was less than 6% RSD and linearity was demonstrated by the Fischer test. Extraction recovery was > 90% and there was a strong linear relationship between authentic and matrix standards. All tested products conformed to the label claim which was strongly correlated with total polyphenols measured by the Folin-Ciocalteau method. Antioxidant activity was measured by the DPPH assay and was found to be strongly correlated with total phenol content and oleuropein concentration.

Phytochemical Composition, Antioxidant, Anti-Helicobacter pylori, and Enzyme Inhibitory Evaluations of Cleistocalyx operculatus Flower Bud and Leaf Fractions.

Six solvent fractions isolated from flower bud and leaf ethanolic extracts of Cleistocalyx operculatus were analyzed for their phytochemical contents, including phenolics, flavonoids, saponins, tannins, and alkaloids. Antioxidant activities were measured using the ABTS, DPPH, and FRAP assays. The results showed that the flower bud aqueous fraction (BAF) and the leaf aqueous fraction (LAF) rich in phenolic content (768.18 and 490.74 mg GAE/g dry extract, respectively) exhibited significantly higher antioxidant activities than the other fractions. The flower bud hexane fraction (BHF) had remarkably high flavonoid and saponin contents (134.77 mg QE/g and 153.33 mg OA/g dry extract, respectively), followed by that of the leaf hexane fraction (LHF) (76.54 mg QE/g and 88.25 mg OA/g dry extract, respectively). The BHF and LHF were found to have extremely high antibacterial activity against two H. pylori strains, ATCC 51932 and 43504 (MICs of 125 µg/mL). Interestingly, DMC (2',4'-Dihydroxy-6'-methoxy-3',5'-dimethylchalcone) isolated from the BHF displayed greater antibacterial activity against the bacterial strains (MICs of 25-50 µg/mL) than those of the fractions. In addition, DMC presented potent inhibitory effects on H. pylori urease (IC50 of 3.2 µg/mL) and α-amylase (IC50 of 83.80 µg/mL), but no inhibition against α-glucosidase. It was also demonstrated that DMC showed pronounced inhibitory effects on the urease activity and biofilm formation of H. pylori, and could increase the membrane permeability of the bacterial cells. Scanning electron micrographs depicted that the BHF and DMC had strong effects on the cell shape and significantly induced the distortion and damage of the cell membrane. The fractions and DMC showed no significant toxicity to four tested human cell lines. Efforts to reduce antibiotic use indicate the need for further studies of the flower buds and DMC as potential products to prevent or treat gastric H. pylori infections.