Search Results (236)

Lipid peroxide (LPO) accumulation and a depletion of intracellular antioxidants are hallmarks of ferroptosis, a controlled iron-dependent form of cell death. Iron chelators and radical scavengers can stop it, while erastin or iron overload can cause it. The main catechin in green tea extract (GTE), epigallocatechin-3-gallate (EGCG), has iron-chelating and antioxidant activities. Herein, we investigated the effects of EGCG-rich GTE on ferroptosis in iron-loaded hepatocytes. The contents of EGCG, total phenolics (TPC), and flavonoids (TFC), as well as ABTS^•+-scavenging activity and cytotoxicity, were determined. Human hepatoma (Huh7) cells were treated with ferric ammonium citrate (FAC) to induce ferroptosis and were co-treated with various concentrations of GTE. Labile iron pool (LIP), reactive oxygen species (ROS), LPO, glutathione (GSH), and glutathione peroxidase 4 (GPX-4) activity were then measured in the cells. One gram of GTE contained 26 mg of EGCG, with a TPC of 172.2 mg gallic acid equivalents and a TFC of 32.9 mg quercetin equivalents. GTE displayed concentration-dependent ABTS^•+-scavenging activity (IC₅₀ = 1.03 mg) that was equivalent to 0.29 mg of Trolox, reporting a Trolox-equivalent antioxidant capacity (TEAC) value of 0.29 mg. High-dose GTE (>100 µM EGCG equivalent) reduced cell viability below 80% (p < 0.05). Intracellular LIP, ROS, and LPO levels were markedly elevated, whereas GSH and GPX-4 activity levels were decreased (p < 0.05) in iron-loaded Huh7 cells. GTE treatment mitigated these alterations in a dose-dependent manner (p < 0.05). These cell-based in vitro findings indicate that EGCG-rich GTE can attenuate ferroptosis-associated oxidative stress in hepatocytes under iron-loading conditions. GTE may serve as a potential dietary antioxidant candidate; further mechanistic studies and in vivo experiments are required to determine its physiological relevance and translational applicability. Full article

In the present study, a comprehensive evaluation of the antioxidant properties of various parts of the hemp plant, specifically its leaves and flowers, in a new feminized variety of Cannabis sativa with an admixture of Cannabis ruderalis was investigated. Methods such as Electron Paramagnetic Resonance (EPR) and UV-visible (UV-vis) spectroscopy were used to assess trolox equivalent antioxidant capacity (TEAC) and total polyphenol content (TPC). TEAC values of the analyzed samples ranged from 29.5 μmol TE/g DW to 150.2 μmol TE/g DW, while TPC varied between 5.4 mg GAE/g DW and 20.3 mg GAE/g DW. The findings indicate that hemp exhibits significant antioxidant properties, especially in its leaves. This is attributed to a diverse range of antioxidants, including cannabinoids, flavonoids, and phenolic compounds, which offer notable health benefits. Furthermore, the method of drying hemp has been shown to influence its antioxidant properties significantly. Research indicates that freeze-dried and air-dried hemp retains higher levels of antioxidant compounds compared to other drying methods. This suggests that selecting an appropriate drying technique is essential for preserving the bioactive compounds responsible for hemp’s antioxidant activity. Full article

Three Australian populations of Portulaca oleracea—Common Purslane, Omega Gold and Omega Red—were grown under identical conditions, separated into portions—leaf, bud, stem and root—and their extracts tested for total phenolic content (TPC), Trolox equivalent antioxidant capacity (TEAC), ferric-reducing antioxidant potential (FRAP), and for antioxidant activity against hydroperoxides and thiobarbituric acid reactive substances (TBARS) in a linoleic acid emulsion. Highest TPC was found in Omega Gold and Omega Red roots, with 31.1 and 36.5 mg gallic acid equivalents per gram dry weight (mg GAE/g DW), respectively, being ten times higher than for Common Purslane roots (3.1 mg GAE/g DW). Other plant portions were generally higher for Omega Gold and Omega Red, though with much less difference, i.e., <2-fold variation. Results from other antioxidant tests paralleled those of TPC. Online monitoring of antioxidant activity via post-column reaction with [2,2′-azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid)] (ABTS^●+), revealed a peak with significant activity. Purification of the compound responsible yielded oleracein australis 1, and 1D and 2D NMR data are presented for the first time. The results of this study show that Australian populations of P. oleracea are high in bioactivity and may be superior to the internationally recognised medicinal plant, Common Purslane. Full article

Coconut oil is highly regarded for its nutritional and functional attributes, making it an attractive candidate for diverse food and health applications. This study evaluates the fatty acid profile, antioxidant and antimicrobial activities, oxidative stability, and sensory properties of selected coconut oils (Coco24, Health, Kospa, Smetol, and Vita) from the Slovak republic market. Acid values (0.09 ± 0.060–0.42 ± 0.060 mg KOH/g) and peroxide values (0.51 ± 0.058–1.20 ± 0.010 mmol O₂/kg) were within recommended safety limits. Oxidative stability varied significantly (p ˂ 0.05), with Smetol showing the highest induction time (124.5 ± 0.98 h) and Coco24 the lowest (25.8 ± 0.22 h). DPPH antioxidant activity was highest in health (469.2 ± 2.01 mg TEAC/kg) and Coco24 (369.3 ± 1.99 mg TEAC/kg) (TEAC—Trolox equivalent antioxidant capacity). Coco24, Health, and Kospa exhibited the most potent antimicrobial activity against Staphylococcus aureus (2.01 ± 0.001 mm, 1.37 ± 0.021 mm, 1.15 ± 0.010 mm, respectively), Candida glabrata (1.17 ± 0.015 mm, 1.17 ± 0.015 mm, 0.45 ± 0.025 mm, respectively), Candida tropicalis (2.12 ± 0.017 mm, 2.13 ± 0.017 mm, 1.52 ± 0.006 mm, respectively), and Bacillus subtilis (1.29 ± 0.055 mm, 1.35 ± 0.006 mm, 0.31 ± 0.020 mm, respectively). FAME analysis revealed that saturated fatty acids dominated, especially in Smetol (97.6 ± 0.067%), while Coco24 had the highest levels of unsaturated fatty acids. Vita and Kospa received the highest panel ratings for smell, taste, and overall acceptability, indicating superior sensory appeal, whereas Smetol scored the lowest. Correlation analysis showed strong positive relationships between MUFA and PUFA (r = 0.986) and taste and acceptability (r = 0.993), as well as between antioxidant activity and Candida albicans inhibition (r = 0.859). Oxidative stability was negatively correlated with PUFA (r = –0.924). PCA grouped oils high in MUFA/PUFA (Kospa, Vita) with superior sensory scores, while PC2 reflected microbial safety. These differences suggest that Coco24, Health, Vita, and Kospa offer enhanced functional and sensory benefits, whereas Smetol is better suited for applications that prioritize oxidative stability. Full article

The increasing demand for red wines, supported by their complex sensory features and rich biochemical composition, has encouraged cultivation in non-traditional viticultural regions. This study investigates the antioxidant potential and volatile composition of three red grape cultivars (Feteasca neagra, Merlot, and Pinot noir) cultivated in the Tarnave Vineyard, Romania, a region historically dedicated to white wines but now increasingly favorable to red varieties due to climate change. Antioxidant capacity, assessed via DPPH, Trolox equivalent antioxidant capacity (TEAC), and Ferric reducing antioxidant power (FRAP) assays, identified Feteasca neagra as the most potent (IC₅₀: 115.32 µg/mL; FRAP: 13.45 mmol TE/L). Gas chromatography–mass spectrometry (GC–MS) profiling identified 61 volatile compounds, with Pinot noir showing the highest concentration (99,018.57 µg/L). Multivariate analysis (ANOVA, PCA) confirmed significant varietal differences and terroir-specific influences on wine composition. Pinot noir was characterized by high levels of higher alcohols, esters, and lactones, yielding a floral and fruity aroma, while Feteasca neagra exhibited intense color, high flavonoid content (notably malvidin-3-glucoside), and vanilla–herbal notes. Merlot presented a balanced sensory profile with significant phenolic acid content. These findings highlight the chemical and sensory potential of the Tarnave Vineyard for premium red wine production. Full article

Background: Fixed-dose combinations have advanced in many therapeutic areas, including otorhinolaryngology, where hearing disorders are increasingly prevalent. Objectives: The present study focuses on developing and evaluating a new capsule combining nicergoline (NIC), piracetam (PIR), and hawthorn extract (HE) for the management of sensorineural hearing loss. Methods: The first phase methodology comprised preformulation studies (DSC, FTIR, and PXRD) to assess compatibility among active substances and excipients. Subsequently, four formulations were prepared and tested for flowability, dissolution behavior in acidic and neutral media, and stability under oxidative, thermal, and photolytic stress. Quantification of the active substances and flavonoids was performed using validated spectrophotometric and HPLC-UV methods. Results: Among the tested variants, the F1 formulation (4.5 mg NIC, 200 mg PIR, 50 mg HE, 2.5 mg magnesium stearate, 2.5 mg sodium starch glycolate, and 240.5 mg monohydrate lactose per capsule) displayed optimal technological properties, superior dissolution in acidic media, and was further selected for evaluation. The antioxidant activity of the formulation was confirmed through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, Trolox Equivalent Antioxidant Capacity (TEAC), and iron chelation tests, and was primarily attributed to the flavonoid content of the HE. Acute toxicity tests in mice and rats indicated a high safety margin (LD₅₀ > 2500 mg/kg), while ototoxicity assessments showed no adverse effects on auditory function. Conclusions: The developed formulation displayed good stability, safety, and therapeutic potential, while the applied workflow could represent a model for the development of future fixed-dose combinations. Full article

Arthrospira platensis (spirulina) is a cyanobacterium containing various phytochemical compounds associated with various antioxidant, antimicrobial, antiviral, anticancer, anti-inflammatory, and immune-promoting properties. The efficacy of ethanolic and methanolic crude extracts of A. platensis regarding antibacterial, antioxidant, and anticancer effects was determined in this study. The ethanolic extract showed the highest antioxidant activity by 8.96 ± 0.84 mg gallic acid equivalent per gram of extract (mg GAE/g extract), 53.03 ± 4.21 mg trolox equivalent antioxidant capacity per gram of extract (mg TEAC/g extract), and 48.06 ± 0.78 mg TEAC/g extract as determined by DPPH, ABTS, FRAP assays, respectively. Moreover, the ethanolic extract showed the highest total phenolic and flavonoid compound contents by 38.79 ± 1.61 mg GAE/g extract and 27.50 ± 0.53 mg of quercetin equivalent per gram of extract (mg QE/g extract). Gallic acid and quercetin in the extracts were also determined by HPLC. The antibacterial activity was evaluated by agar well diffusion and broth dilution methods on skin pathogenic bacteria, including Staphylococcus aureus, Staphylococcus epidermidis, methicillin-resistant S. aureus (MRSA), Micrococcus luteus, Pseudomonas aeruginosa, and Cutibacterium acnes. The inhibition zone of A. platensis extracts ranges from 9.67 ± 0.58 to 12.50 ± 0.50 mm. In addition, MIC and MBC values ranged from 31.25 to 125 mg/mL. The inhibition of biofilm formation and biofilm eradication by A. platensis ethanolic extract was 87.18% and 99.77%, as determined by the crystal violet staining assay. Furthermore, the anticancer activity of A. platensis on A375 human melanoma cells was examined. The ethanolic and methanolic extracts induced DNA apoptosis through both intrinsic and extrinsic pathways by upregulating the expression of caspase-3, caspase-8, and caspase-9. These findings suggested that A. platensis demonstrated promising antioxidant, antibacterial, and anticancer activities, emphasizing its potential as a natural therapeutic agent for the management of pathological conditions. Full article

This study aimed to optimize the extraction of phytocompounds intended for wound care applications from three plant species, Sambucus nigra L. flowers and Epilobium hirsutum L. and Lythrum salicaria L. aerial parts, by using a Quality by Design approach. The effects of different extraction methods (ultra-turrax and ultrasonic-assisted extraction), ethanol concentrations (30%, 50%, 70%), and extraction times (3, 5, 10 min) were studied, and during the optimization step, the polyphenol and flavonoid contents were maximized. The phytochemical profiles of the optimized HEs (herbal extracts) were assessed using LC-MS/MS methods. The antioxidant capacity of the optimized HEs was determined using DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity) TEAC (Trolox equivalent antioxidant capacity), and FRAP (ferric reducing antioxidant power) assays, while the antibacterial activity was evaluated against Escherichia coli, Pseudomonas aeruginosa, and MSSA—methicillin-sensitive Staphylococcus aureus and MRSA—methicillin-resistant Staphylococcus aureus). Cell viability and antioxidant and wound healing potential were assessed on keratinocytes and fibroblasts. The anti-inflammatory effect was assessed on fibroblasts by measuring levels of interleukins IL-6 and IL-8 and the production of nitric oxide from RAW 264.7 cells. The major compounds of the optimized HEs were rutin and chlorogenic acid. The Lythrum salicaria optimized HE showed the strongest antibacterial activity, while the Sambucus nigra optimized HE demonstrated high cell viability. Lythrum salicaria and Epilobium hirsutum optimized HEs showed increased antioxidant capacities. All extracts displayed anti-inflammatory effects, and the Epilobium hirsutum optimized HE exhibited the best in vitro wound-healing effect. Full article

Background: Opuntia ficus-indica (OFI) cladodes are valuable and underestimated by-products that provide significant amounts of biologically active compounds. In this paper, microwave-assisted extraction (MAE) was performed for the recovery of phenolic compounds from OFI cladodes using two approaches: response surface methodology (RSM) and artificial neural network–genetic algorithm (ANN-GA), which were then compared following statistical indicators. Materials and Methods: Four independent factors were employed in the optimization process (solvent concentration, microwave power, irradiation time, and solid-to-liquid ratio) by selecting the total phenolic content (TPC), estimated by the Folin–Ciocalteu method, as a response. The optimized extract was tested for antioxidant capacity using the Folin–Ciocalteu reagent, Trolox Equivalent Antioxidant Capacity (TEAC), and oxygen radical absorbance capacity (ORAC) assays and for antimicrobial activity against 16 pathogenic strains using the agar well diffusion method. Results: The maximum TPC values predicted with maximizing desirability function for RSM were 2177.01 mg GAE/100 g DW and 1827.38 mg GAE/100 g DW for the ANN. Both models presented certain advantages and could be considered reliable tools for predictability and accuracy purposes. Using these conditions, the extract presented high antioxidant capacity for FCR assay (13.43 ± 0.62 mg GAE/g DW), TEAC (10.18 ± 0.47 µmol TE/g DW), and ORAC (205.47 ± 19.23 µmol TE/g DW). The antimicrobial activity of the optimized extract was pronounced only with respect to S. aureus alimentarius, Streptococcus, E. coli, P. aeruginosa, and A. flavus. Conclusions: This study underlines the high effectiveness of the optimization approaches in providing a maximum recovery of bioactive compounds from OFI cladodes to formulate food and pharmaceutical products with functional qualities. Full article

This study aimed to evaluate the feasibility of producing and characterizing Cistus creticus L. powders obtained through spray drying and freeze drying using maltodextrin and inulin as carriers. Quantitative and qualitative analysis of polyphenols by high-performance liquid chromatography with diode-array detection (HPLC-DAD) and high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) identified key bioactive compounds, including punicalagin isomers and their galloyl esters, as well as flavonoids (myricetin-3-galactoside, myricetin-3-rhamnoside, quercetin-3-galactoside, and tiliroside). Phenolics in powders produced by both drying techniques ranged from 73.2 mg to 78.5 mg per g of dry matter. Inulin proved to be as effective as maltodextrin in spray drying, offering a promising alternative for plant-based powder formulation. Antioxidant capacity measured by Trolox equivalent antioxidant capacity assay with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (TEAC ABTS) and ferric reducing antioxidant power (FRAP) assay indicated that spray-dried powders with inulin exhibited antioxidant properties comparable to those with maltodextrin. The results demonstrated that Cistus creticus L. powders obtained with inulin can serve as valuable sources of bioactive compounds with potential health benefits similar to those obtained with maltodextrin. Moreover, from a technological perspective, inulin proved to be an equally efficient carrier in terms of production-process parameters such as moisture content and water activity, making it a viable alternative to maltodextrin in plant-based powder formulations. Full article

Spent coffee grounds constitute a waste product that has attracted potential interest as a rich source of secondary metabolites such as polyphenolic compounds with antioxidant properties. In this work, aqueous extracts from samples of different spent coffee grounds from Costa Rica were prepared and analyzed using ultra-performance liquid chromatography coupled with high-resolution mass spectrometry using a quadrupole time-of-flight analyzer (UPLC-QTOF-ESI MS). This allowed for the identification of twenty-one compounds, including fourteen phenolic acids, three caffeoylquinic lactones, and four atractyligenin diterpenes. In addition, using UPLC coupled with a diode array detector (UPLC-DAD), we quantified the levels of caffeine (0.55–3.42 mg/g dry weight [DW]) and six caffeoylquinic and feruloylquinic acids (0.47–5.34 mg/g DW). The highest value was found for the fine-grind sample (EXP), both for phenolic acids and for total polyphenols (9.59 mg gallic acid equivalents [GAE]/g DW), compared to 2.13 and 1.70 mg GAE/g DW for the medium-grind (GR) and coarse-grind samples (PCR), respectively. The results obtained from the antioxidant evaluations using the 2,2-diphenyl-1-picrylhydrazyl assay (IC₅₀ 0.0964–6.005 g DW/L), the ferric-reducing antioxidant power (PFRAP) analysis (0.0215–0.1385 mmol FeSO₄/g DW), the oxygen radical absorbance capacity (ORAC) assessment (45.7–309.7 μmol Trolox/g DW), and the Trolox equivalent antioxidant capacity (TEAC) assay (3.94–23.47 mg Trolox/g DW) also showed the best values for the fine-grind sample, with results similar to or higher than those reported in the literature. Statistical Pearson correlation analysis (p < 0.05) indicated a high correlation (R ≥ 0.842) between all antioxidant analyses, the total polyphenols, and the phenolic acid quantification using UPLC-DAD. These results show the potential for further studies aiming to exploit this waste product’s bioactive properties, constituting the first detailed study of spent coffee grounds from Costa Rica. Full article

Apple pomace, a by-product of apple juice production, is typically discarded as waste. Recent approaches have focused on utilizing apple pomace by extracting beneficial bioactive compounds, such as antioxidant phenolic compounds (PCs). Before these PC-rich extracts can be used in food products, they must undergo food preservation and processing methods. However, the effects of these processes on the composition, stability, and properties of the PC remain insufficiently understood. The present study aimed at investigating the effects of a thermal treatment (TT), a high-pressure thermal treatment (HPTT), and a pulsed electric field treatment (PEF) on the composition and antioxidant activity of PC-rich apple pomace extracts (APEs). Major PCs, including phloridzin, chlorogenic acid, and epicatechin, as well as minor compounds, were identified by liquid chromatography–tandem mass spectrometry (LC-MS/MS) and high-performance thin-layer chromatography (HPTLC). As a stability indicative property, the antioxidant activity was analyzed by a Trolox equivalent antioxidant capacity assay (TEAC), electron paramagnetic resonance spectroscopy, and the Folin–Ciocalteu reagent assay. The results showed that TT at 80 °C increased phloridzin content, likely due to the hydrolysis of bound forms, while higher temperatures and HPTT resulted in a substantial PC conversion. The PEF treatment also caused notable PC conversion, but generally, it had a milder effect compared to TT and HPTT. Hence, low temperatures with and without high pressure and PEF seem to be the most promising treatments for preserving the highest content of major PC in APE. Antioxidant activity varied among the analytical methods, with HPTT showing minor changes despite PC loss compared to the untreated APE. This suggests that other antioxidant compounds in the extracts may contribute to the overall antioxidant activity. This study demonstrates that apple pomace contains valuable PC, highlighting its potential as a health-promoting food additive and the impact of conventional preservation and processing methods on PC stability. Full article

Spinacia oleracea L. cultivar platypus leaves are identified as a functional food due to their nutrient composition which promotes health beyond basic nutrition. Considering the increasing use of food supplements, S. oleracea baby leaves have been extracted by maceration, solid–liquid dynamic extraction (SLDE)-Naviglio, and ultrasound-assisted extraction (UAE) using EtOH and EtOH:H₂O mixtures. The analysis of the extracts by using LC-ESI/HRMSMS revealed 42 compounds (flavonoids, polar lipid derivatives, and 20-hydroxyecdysone), along with primary metabolites, detected by NMR analysis. A principal component analysis (PCA) of LC-ESI/HRMS and NMR data was performed, revealing how 20-hydroxyecdysone and flavonoids, the specialized metabolites mainly responsible for the biological activity of S. oleracea leaves, occurred in the highest amount in the EtOH and EtOH:H₂O (70:30, v/v) extracts obtained by SLDE-Naviglio extraction. 20-hydroxyecdysone was also quantified in all the extracts via LC-ESI/QTrap/MS/MS using the Multiple Reaction Monitoring (MRM) method. The EtOH extracts obtained by SLDE-Naviglio and maceration showed the highest content (82.16 and 81.27 mg/g extract, respectively). The total phenolic content (118.35–206.60 mg GAE/g), the flavonoid content (10.90–41.05 mg rutin/g), and the Trolox Equivalent Antioxidant Capacity (TEAC) (1.63–2.05 mM) of the extracts were determined. The EtOH:H₂O (70:30, v/v) extract analyzed by using SLDE-Naviglio showed the highest phenolic and flavonoid content and radical scavenging activity. Full article

Determining the total antioxidant capacity (TAC) of biological samples is a valuable approach to measuring health status under oxidative stress conditions, such as infertility and type 2 diabetes. The Trolox equivalent antioxidant capacity (TEAC) assay is the most common approach to evaluating TAC in biological matrices. This assay is typically performed in clinical settings on a microtiter plate using a plate reader. However, the instrumentation and expertise requirements, and the resulting delay in the reporting of assay outcomes, make solution-based TEAC assays impractical for point-of-care or at-home testing, where individuals may want to monitor their health status during treatment. This work introduces the first microfluidic paper-based analytical device (µPAD) that measures TAC in human serum using TEAC assay chemistry. TAC was determined through a colorimetric image analysis of the degree of decolorization of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cations (ABTS^●+) by serum antioxidants. The µPAD showed a linear response to Trolox, ranging from 0.44 to 2.4 mM, (r  =  0.999). The performance of paper-based TEAC assays was validated through direct comparison to solution-based TEAC assays. There was a 0.04 mM difference in TAC values between the two platforms, well within one standard deviation of a standard solution-based assay conducted on an aliquot of the same serum sample (±0.25 mM). The µPAD had a limit of detection (LOD) of 0.20 mM, well below the TAC of normal human serum. The results suggest that the proposed device can be used for biological TAC determination and expands the field of TAC analysis in point-of-care health monitoring. Full article

Macrocystis pyrifera is a brown seaweed widely distributed on the coast of Chile, with a high content of polyphenolic compounds with antioxidant properties. The effects of its inclusion in the diet on oxidative stress in dairy cows have not been evaluated. Therefore, this study aimed to evaluate the effect of two doses of inclusion of Macrocystis pyrifera on pro-oxidant and antioxidant indicators in grazing dairy cows. Thirty-six mid-lactating and clinically healthy Holstein-Friesian cows were randomly assigned to one of three diets: Control (75% perennial ryegrass and 25% commercial concentrate); Treatment 1 (control diet and 1.5% inclusion of seaweed); and Treatment 2 (control diet and 3% inclusion of seaweed). Blood samples were taken by coccygeal venipuncture on days 18, 45, and 61 to determine the plasma concentration of malondialdehyde (MDA), Trolox equivalent antioxidant capacity (TEAC), and oxidant stress index (OSI). No significant differences were observed between groups regarding MDA, TEAC, and OSI. However, an interaction was observed, where at 45 and 61 days, the OSI of the cows was lower in Treatment 2 compared to the Control. Including 1.5% and 3% of Macrocystis pyrifera in the diet of grass-fed cows did not affect the oxidative stress indicators during mid-lactation. Full article