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Erectile dysfunction (ED) which is the inability to maintain an erection during sexual activity, is one of the most prevalent sexual dysfunctions, with mild to severe ED affecting an estimated 5-20% of men globally and about 322 million men may be affected globally by 2025.

Pinus roxburghii and Pinus wallichiana are traditionally plants used for various medicinal purposes worldwide. The present study focused on evaluating the phytochemical compounds and the free radical scavenging potential in various parts of P. roxburghii and P. wallichiana through in vitro and in silico study. Crude extract of the fresh leaves was obtained using methanol while steam distillation method was used for the extraction of the essential oil. The phytochemicals were determined by standard methods. Antioxidant Potential of the phytochemicals was performed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), Hydroxyl radical (OH) inhibition, Ferric ion reducing power (FRAP) and Phosphomolybedenum complex (PMC) assays. The interactions between the total phenolics and flavonoids of the selected plants and virulent target proteins of the pathogenic bacteria were identified, characterized, and examined using Molecular Operating Environment (MOE) software. The fresh leaves of P. roxburghii, exhibited the highest total phenolic (744.6 ± 27.0 mg GAE/100 g) and carotenoid content (21.4 ± 0.4 mg/g) that was significantly varied from other samples. The EO of P. wallichiana, showed the highest total flavonoid content. In P. roxburghii and P. wallichiana, the fresh leaves exhibited the highest percentage of scavenging potential against the DPPH radical. Additionally, the EO from P. roxburghii and P. wallichiana have significant potential to reduce ferric ions, and molybdate ions, respectively) with significant differences. The molecular docking showed a significant interaction of compounds present in these pines leaves with Exotoxin A and Elastase B proteins. The essential oil (EO), hydrosol (HS), and crude extract derived from P. roxburghii and P. wallichiana could be exploited as natural sources of antioxidants, anti-inflammatory agents, and innovative medications against the human pathogen, Pseudomonas aeruginosa.

Background: Finding herbal herbicides with biodegradability and selectivity against weeds is an interesting and vital challenge for human health. The study was considered to analyze the phytochemical profile, phytotoxicity and biological activities of Rindera lanata together with a molecular docking perspective. The study was considered to analyze the phytochemical profile, phytotoxicity and biological activities of Rindera lanata together with a molecular docking perspective. Methods: Aerial parts of R. lanata were successively solvent extracted with the Soxhlet apparatus, followed by maceration. Different chromatography methods were employed to isolate and purify the major compounds of the plant. The compounds were assigned by spectroscopic methods, containing 1D and 2D NMR (Nuclear Magnetic Resonance). Several in vitro antioxidant assays, together with an antimicrobial assay, alongside the allelopathic property on the germination of Cuscuta campestris seeds, were assessed upon the extracts. As a final point, molecular docking was conducted to evaluate the interactions among the identified compounds with 4-hydroxyphenyl pyruvate dioxygenase (HPPD), glutamine synthetase (GS), and acetohydroxyacid synthetase (AHAS). Results: Phytochemical analysis of the extracts led to the identification of a new flavonoid 3, 5, 4’-tri-O-methylquercetin (1), apigenin (2), chrysoeriol (3), luteolin-7-O-glucoside (4) and rutin (5). It was exposed that ethyl acetate extract not only illustrated the highest antioxidant effect in all the in vitro assays but also exhibited the maximum antibacterial effect against Staphylococcus epidermidis. Effectively, it showed conventional allelopathic activity in preventing germination, seedling length and seedling weight growth of C. campestris seeds, as well as a concentration-dependent enhancement (p≤0.05). Docking analysis results indicated that rutin had a good affinity for HPPD, GS and AHAS enzymes, with docking score values of -11.454, -10.422 and -10.152 kJ/mol, respectively. Conclusion: The present study suggested that isolated flavonoids from R. lanata could be used as the lead compounds in the development of natural herbicides for strong bonds in the active region of HPPD, GS and AHAS enzymes.

ABSTRACT: Orange-fleshed non-netted honeydew melon has high nutritional and economic potential, being widely appreciated as a refreshing sweet fruit. Therefore, evaluating commercial samples of such relevant products for the fresh fruit market is of great importance. This study investigated the antioxidant capacity, quality parameters, and chemical composition of honeydew melons from the Brazilian market. The values of pH and °Brix determined for melon samples were 6.5 ± 0.30 and 9.2 ± 0.80 g/100 g (fresh weight), respectively, which agree with the results expected for high-quality melons. The chromatography analysis revealed sucrose (49% of total sugar) as the main sugar, followed by fructose (30%) and glucose (21%). Carotenoids, which are directly linked to the characteristic orange color, showed a total level of 270.59 µg/g (dry weight). Additionally, the higher b* value compared to a* value indicates the highest yellow contribution. Regarding the antioxidant assays, in addition to presenting antioxidant capacity for both methods applied, DPPH and FRAP, levels ranging from 16.40 ± 0.21 µmol ascorbic acid equivalent/g to 56.98 ± 0.80 µmol Trolox equivalent/g (dry weight) were reported in melon extracts. Moreover, the results were higher in terms of FRAP than DPPH. Therefore, the results underscore the evaluated honeydew melons as valuable sources of bioactive compounds, such as carotenoids and phenolics, which contribute to their antioxidant properties. Besides, analyses of color, pH, and total soluble solids content also reflect the quality attributes.

Our group has seen great promise in using substituted diaryl-hydrazones to alleviate oxidative stress in preeclampsia. Specifically, fluorinated diaryl-hydrazones have shown great efficacy, confirmed via antioxidant assays and animal trials using pregnant mice. In addition to efficient antioxidant properties, these diaryl-hydrazones are also considered non-toxic. While the synthesis of these compounds is relatively simple, it commonly utilizes undesirable solvents and glacial acetic acid as the catalyst; additional solvents are needed for the isolation of the desired products, which negatively affects the green synthesis of the hydrazones. To combat this possible industrial roadblock, we have begun incorporating the use of hydrostatic high pressure (HHP) in the synthesis. The use of HHP allowed us to synthesize substituted diaryl-hydrazones in a 1:1 molar ratio without the need for solvents or acid catalysts. The optimized procedure can produce nearly quantitative yields, leading to an easier isolation of the products. Different HHP methodologies, such as constant high-pressure treatment and cycling (with different number of cycles, holding and decompression times) were applied and cycling was observed to be the most efficient activation for the majority of the reactions. Stability experiments were also conducted with one of the products and observed that although the solid-state storage does not alter the hydrazone, storing it in various solvents may significantly decrease the concentration of the active component which should be considered when performing the biochemical/biological assays.

Cynanchum auriculatum Royle ex Wight (CA) is a traditional medicinal and edible plant in China. This study aimed to isolate and characterize the phenolic compounds of C. auriculatum to identify its main antioxidant constituents. Polyphenols were extracted using an ultrasound-assisted ethanol extraction method, followed by partitioning with ethyl acetate. The ethyl acetate extract was then purified through thin-layer chromatography, silica gel column chromatography, and reverse-phase silica gel column chromatography. Three monomeric compounds—cynandione A (I), 2,5-dihydroxyacetophenone (II), and radix piperacanthone (III)—were identified through their physical and chemical properties, UV and IR spectra, and liquid chromatography–mass spectrometry (LC-MS/MS). Vitamin C (VC) and 2,4-dihydroxyacetophenone were used as controls to evaluate the antioxidant potential of the two most abundant monomers. Antioxidant assays demonstrated that 2,5-dihydroxyacetophenone and cynandione A exhibited strong antioxidant activity at lower concentrations, whereas 2,4-dihydroxyacetophenone showed significantly weaker activity. Furthermore, cynandione A displayed superior cellular antioxidant activity compared to 2,5-dihydroxyacetophenone, indicating its potential as a promising bioactive compound. In conclusion, this study provides valuable insights into the phenolic composition of C. auriculatum and highlights cynandione A as a key antioxidant, paving the way for future research on its therapeutic applications.

Background/Objectives: Phloroglucinol (PHL), a phenolic compound extracted from the brown alga Rosenvingea intricata, exhibits potent antioxidant and anticancer properties. This study aims to extract, purify, and characterize PHL, and further develop functionalized zinc oxide nanoparticles (ZnO NPs) loaded with PHL to enhance its therapeutic potential. Methods: PHL was extracted using acetone and purified through Sephadex LH-20 column chromatography, yielding a highly enriched fraction (F-3). The purified compound was characterized by FTIR, HPLC, NMR, and LC-MS. ZnO NPs were synthesized, PEGylated, and conjugated with PHL, forming ZnO-PEG-PHL NPs. Their characterization included DLS, zeta potential, XRD, SEM-EDAX, and encapsulation efficiency studies. Antioxidant assays (DPPH, FRAP, ABTS, RPA) were performed and in vitro cytotoxicity on A549 lung cancer cells were determined to evaluate the therapeutic efficacy of PHL. Results: The purified PHL fraction showed a high phenolic content (45.65 PHL mg/g), which was was confirmed by spectral analysis. The ZnO-PEG-PHL NPs increased in size from 32.36 nm to 46.68 nm, with their zeta potential shifting from −37.87 mV to −26.82 mV. The antioxidant activity was superior for the ZnO-PEG-PHL NPs in all assays, while the in vitro cytotoxicity tests showed an IC50 of 40 µg/mL compared to 60 µg/mL for the ZnO NPs and 70 µg/mL for PHL. Apoptotic studies revealed significant cell cycle arrest and apoptosis induction. Conclusions: The synthesized ZnO-PEG-PHL NPs demonstrated enhanced antioxidant and anticancer properties, making them promising candidates for cancer therapy and antioxidant applications.

The process of developing of new drugs is greatly hampered by their inadequate physicochemical, pharmacokinetic, and intrinsic characteristics. In this regard, the selected chloro indolinone, (Z)-6-chloro-3-(2-chlorobenzylidene)indolin-2-one (C1), and nitro indolinone, (Z)-6-chloro-3-(2-nitrobenzylidene)indolin-2-one (C2), were subjected to SwissADME and density function theory (DFT) analysis. For compounds C1 and C2, the BOILED-Egg pharmacokinetic model predicted intestinal absorption, blood–brain barrier (BBB) penetration, and p-glycoprotein interaction. According to the physicochemical analysis, C1 has exceptional drug-like characteristics suitable for oral absorption. Despite only being substrates for some of the major CYP 450 isoforms, compounds C1 and C2 were anticipated to have strong plasma protein binding and efficient distribution and block these isoforms. The DFT study using the B3LYP/6-311G(d,p) approach with implicit water effects was performed to assess the structural features, electronic properties, and global reactivity parameters (GRP) of C1 and C2. The DFT results provided further support for other studies, implying that C2 is more water-soluble than C1 and that both compounds can form hydrogen bonds and (weak) dispersion interactions with other molecules, such as solvents and biomolecules. Furthermore, the GRP study suggested that C1 should be more stable and less reactive than C2. A concentration-dependent 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity was shown by both C1 and C2. In brief, this finding has provided a strong foundation to explore further the therapeutic potential of these molecules against a variety of human disorders.

Stevia rebaudiana Bertoni, a no-calorie natural sweetener, contains a plethora of polyphenols that exert antioxidant properties with potential medicinal significance. Due to the variety of functional groups, polyphenols exhibit varying solubility depending on the nature of the extraction solvents (water, organic, or their mixtures, defined further on as hydroalcoholic extracts). In the present study, we performed a systematic review, following PRISMA guidelines, and meta-analysis, synthesizing all available data from 45 articles encompassing 250 different studies. Our results showed that the total phenolic content (TPC) of hydroalcoholic and aqueous extracts presents higher values (64.77 and 63.73 mg GAE/g) compared to organic extracts (33.39). Total flavonoid content (TFC) was also higher in aqueous and hydroalcoholic extracts; meta-regression analysis revealed that outcomes in different measuring units (mg QE/g, mg CE/g, and mg RUE/g) do not present statistically significant differences and can be synthesized in meta-analysis. Using meta-regression analysis, we showed that outcomes from the chemical-based ABTS, FRAP, and ORAC antioxidant assays for the same extract type can be combined in meta-analysis because they do not differ statistically significantly. Meta-analysis of ABTS, FRAP, and ORAC assays outcomes revealed that the antioxidant activity profile of various extract types follows that of their phenolic and flavonoid content. Using regression meta-analysis, we also presented that outcomes from SOD, CAT, and POX enzymatic antioxidant assays are independent of the assay type (p-value = 0.905) and can be combined. Our study constitutes the first effort to quantitatively and statistically synthesize the research results of individual studies using all methods measuring the antioxidant activity of stevia leaf extracts. Our results, in light of evidence-based practice, uncover the need for a broadly accepted, unified, methodological strategy to perform antioxidant tests, and offer documentation that the use of ethanol:water 1:1 mixtures or pure water can more efficiently extract stevia antioxidant compounds.

Introduction: Local anesthetics are widely recognized pharmaceutical compounds with various clinical effects. Recent research indicates that they positively impact the antioxidant system and they may function as free radical scavengers. We hypothesize that their scavenging activity is influenced by the lipophilicity of the environment.Methods: We assessed the free radical scavenging capacity of three local anesthetics (lidocaine, bupivacaine, and ropivacaine) using ABTS, DPPH, and FRAP antioxidant assays. We also employed quantum chemistry methods to find the most probable reaction mechanism. The experiments were conducted in an aqueous environment simulating extracellular fluid or cytosol, and in a lipophilic environment (n-octanol) simulating cellular membranes or myelin sheets.Results: All local anesthetics demonstrated ABTS˙+ radical scavenging activity, with lidocaine being the most effective. Compared to Vitamin C, lidocaine exhibited a 200-fold higher half-maximal inhibitory concentration. The most thermodynamically favorable and only possible reaction mechanism involved hydrogen atom transfer between the free radical and the -C-H vicinal to the carbonyl group. We found that the antioxidant activity of all tested local anesthetics was negligible in lipophilic environments, which was further confirmed by quantum chemical calculations.Conclusion: Local anesthetics exhibit modest free radical scavenging activity in aqueous environments, with lidocaine demonstrating the highest activity. However, their antioxidant activity in lipophilic environments, such as cellular membranes, myelin sheets, and adipose tissue, appears to be negligible. Our results thus show that free radical scavenging activity is influenced by the lipophilicity of the environment.

Nutrition has crucial effects and a significant role in disease prevention. Recently, nutraceuticals have attracted much attention in scientific research due to their pleiotropic effects and relatively non-toxic behavior. Among the biological effects displayed by plants belonging to the Lamiaceae family, such as antibacterial, anticancer, anti-inflammatory, and anticholinesterase, sage is well known for its antioxidant properties and is a rich source of numerous compounds that are biologically active, amongst them polyphenols, with more than 160 types identified. In this review we summarized some of the significant studies published in the last decade reporting the most employed extraction methods and the different assays that are useful for establishing the antioxidant properties of some sage species. Even though the scientific literature contains plenty of data regarding the antioxidant properties of many sage species, further studies are needed in order to gain a deeper understanding of the mechanism of action and the compounds responsible for their antioxidant activity. Finally, it should be taken into account that the data on the antioxidant properties of sage extracts are often difficult to compare with each other, since a series of variables in the extraction procedures, the type of assay used, and standardization may affect the final result.

Vegetables are one of the most preferred food commodities and can be consumed either raw or as processed due to their health-promoting nutrients. In the present work, analysis of pharmacognostical standards, antioxidant capacity, and separation of phytocompounds through thin layer chromatography (TLC) from cabbage, cauliflower, pea, carrot, and potato peels were carried out. Microscopic analysis revealed the presence of wood fibers, trichomes, crystals, and annular xylem vessels in the vegetable peels. Physicochemical analysis showed that all the vegetable peel samples which were analysed have low (7.08%-10%) moisture content. The total ash content of vegetable peels varied in cauliflower peels (1.95±0.58) to the peels of pea (19.86±1.9). The content of acid insoluble ash varied from 1.46±0.63 to 3.09±0.59 in cauliflower and pea. Potato peel has the lowest water-soluble ash content (1.16±1.90) as compared to other peels. The highest pH value was found in the peels of pea (7), while the lowest pH was found in the peels of cabbage (4). Among all extracts, the petroleum ether extract has shown the greatest yield (5.6±0.45). The fluorescence analysis showed various colours like green, brown, pale green, and yellow under different chemical treatments. Different types of pri-secondary metabolites were detected in small, moderate, and high amounts and notified to provide numerous health benefits to humans. In case of DPPH assay, aqueous extract of cauliflower has shown the low value of IC50 (24.82 µg/ml) in comparison to standard, suggested the higher antioxidant activity of the extract. Among all the extracts, aqueous and methanol extracts of cauliflower have shown the better reducing and total antioxidant activity in comparison to standard. TLC profiling of methanolic extract of cabbage and cauliflower peels revealed the presence of different compounds of varying Rf values. Above results indicate that the food waste consists of valuable components and may be utilized as noticeable and cheap source in pharmaceuticals for the treatment of several life-threatening diseases.

Ubiquitously present in plant life, coumarins, as a class of phenolic compounds, have multiple applications—in everyday life, in organic synthesis, in medicine and many others. Coumarins are well known for their broad spectrum of physiological effects. The specific structure of the coumarin scaffold involves a conjugated system with excellent charge and electron transport properties. The antioxidant activity of natural coumarins has been a subject of intense study for at least two decades. Significant research into the antioxidant behavior of natural/semi-synthetic coumarins and their complexes has been carried out and published in scientific literature. The authors of this review have noted that, during the past five years, research efforts seem to have been focused on the synthesis and examination of synthetic coumarin derivatives with the aim to produce potential drugs with enhanced, modified or entirely novel effects. As many pathologies are associated with oxidative stress, coumarin-based compounds could be excellent candidates for novel medicinal molecules. The present review aims to inform the reader on some prominent results from investigations into the antioxidant properties of novel coumarin compounds over the past five years.

In the present work, complexes of cobalt(II), copper(II), and zinc(II), 2-amino-4-methylpyrimidineand, and 2,3-diaminopyridine were successfully prepared and characterized using elemental analysis, UV-visible, and FTIR spectroscopy, as well as magnetic susceptibility measurements, molar conductance, TGA analysis, and X-ray diffraction. From elemental and spectral data, the formulae [M(L1)(L2)Cl2(H2O)] (where L1 = AMPY (2-amino-4-methylpyrimidine) and L2 = DAPY(2,3-diaminopyridine)) and M = Co(II) (2), Cu(II) (2), and Zn(II)) for the metal complexes have been proposed. The geometric structures of the mixed-ligand complexes were found to be octahedral around the metal ions, and the XRD patterns showed monoclinic crystal systems with space group P21. The mode of bonding was pentacoordinate for Cu and hexacoordinate for Zn and Co. Different features may result from the fact that not all molecules have the same electron distribution. For example, Zn and Co have larger electron densities in at least one of the chlorides in the HOMO compared with pentacoordinate Cu, which has a small electron distribution on the chloride. Thermal analysis indicated that all metal complexes are stable up to about 88 °C with thermodynamically favored overlapped chemical reactions. Excellent antibacterial and antifungal activity was shown by the three synthesized forms of the complexes. The Zn(II) complex had a high level of antioxidant activity with a DPPH scavenging of 91.5%, whereas the Cu(II) complex had a low level of antioxidant potential (16.5%). The docking tests also showed that all compounds had good binding energy levels (7.2–7.9 kcal mol−1). For this reason, all molecules can easily fit in the receptor protein’s catalytic sites. However, the Co(II) complex is shown to be more active.

Aconitum chasmanthum Stapf ex Holmes, an essential and critically endangered medicinal plant from Kashmir Himalayas, was studied for its antioxidant and antifungal properties. The shade-dried powdered rhizome was extracted sequentially with hexane, ethyl acetate, and methanol. These subsequent fractions were evaluated for total phenolic content (TPC); total flavonoid content (TFC); antioxidant assays, such as 1,1-diphenyl 1-2-picryl-hydrazyl (DPPH); ferric-reducing antioxidant power (FRAP); superoxide radical scavenging (SOR); hydroxyl radical scavenging (OH) and antifungal activity using the poisoned food technique. Highest TPC (5.26 ± 0.01 mg/g) and TFC (2.92 ± 0.04 mg/g) were reported from methanolic extracts. The highest values of radical scavenging activities were also observed in methanolic extracts with IC50 values of 163.71 ± 2.69 μg/mL in DPPH, 173.69 ± 4.91 μg/mL in SOR and 159.64 ± 2.43 μg/mL in OH. The chemical profile of ethyl acetate extract was tested using HR-LCMS. Methanolic extracts also showed a promising inhibition against Aspergillus niger (66.18 ± 1.03), Aspergillus flavus (78.91 ± 1.19) and Penicillium notatum (83.14 ± 0.97) at a 15% culture filtrate concentration with minimum inhibitory concentration (MIC) values of 230 μg/mL, 200 μg/mL and 190 μg/mL, respectively. Overall, the methanolic fractions showed significant biological potential, and its pure isolates might be used to construct a potential new medicinal source.

Objective: To explore the new sources of novel bioactive compounds having pharmaceutical and agricultural interest and to search the endophytic actinobacteria from medicinal plants. Methods: NAF-1 an endophyte actinobacteria was isolated from leaves of medicinal plant Aloe vera collected in Marrakesh, Morocco using Bennett agar as selective medium. NAF-1 was tested for its antimicrobial activity against five pathogenic bacteria such as Staphylococcus aureus PIC 53156, Micrococcus luteus ATCC381, Bacillus subtilis ATCC 14579, Pseudomonas aeruginosa DSM 50090 and Escherichia coli ATCC 8739 and four human clinic fungi belonging to the Candida, Aspergillus and Microsporum genera. Several antioxidant activities were studied such as DPPH free radical scavenging, β -carotene and linoleic acid and reducing power assays. The total of phenol and flavonoid was also calculated. Using Artemia salina shrimp assay, the cytotoxicity of NAF-1 crude extract was determined. Results: The results revealed that the actinobacteria showed a high activity (≥20 mm) against only Gram positive bacteria but it had a moderate activity (between 13 and 15 mm) against Human clinic fungi. The isolate also exhibited a LD50 of 14.20 μg/mL in the cytotoxicity assay. The result showed that the crude extract presented an interesting free radical-scavenging activity with IC50 value of (5.58 ± 0.26) μg/mL and a high value of phenolic and flavonoid compounds with (15.41 ± 0.18) μg GAE/mg extract and (11.41± 0.06) μg QE/mg extract respectively. Moreover, the taxonomic position of our endophyte actinobacteria using the morphological and physiological criteria and using 16S rRNA gene sequence (polyphasic approach) showed that the NAF-1 isolate was similar to Streptomyces hydrogenans which was never described as an endophyte actinobacteria. Conclusions: This isolated strain appears promising resources of bioactive agents and can be exploited to produce therapeutic agents active against pathogenic disease.

This study reports the effect of an acetone extract of Evernia prunastri on the micronucleus distribution of human lymphocytes and effect on cholinesterase activity. Furthermore, the antioxidant activity (estimated via DPPH, ABTS, TRP and CUPRAC assays), as well as total phenolic compounds (TPC) and antibacterial activity (against two Gram-positive and three Gram-negative bacteria) were determined. Chemical profiling of four E. prunastri extracts (acetone, diethyl ether, ethyl acetate and dichloromethane) was realized by GC–MS and HPLC analysis. In addition, the activity concentrations of 40K, 137Cs, 226Ra and 232Th were established.

In this research, supercritical CO2 extraction is applied to extract bioactive compounds from Lamium album (white dead nettle, Lamiaceae). Extraction was performed at various temperatures (40, 50, and 60 °C) using methanol as co-solvent at a constant flow rate of CO2, methanol, and pressure. The collected extracts were characterized in terms of antioxidant capacity by using DPPH, ABTS and FRAP in vitro antioxidant activity assays, whereas the Folin–Ciocalteu procedure was employed to estimate the total phenols content (TPC). On the other hand, phenolic compounds in the extracts were quantitated by liquid chromatography coupled with a photodiode array detector (UPLC-PDA) and confirmed with a mass detector (TQD). The extracts have shown high TPC ranged between 234.17 to 650.17 mg GAE/g extract. DPPH scavenging of the extracts was estimated and obtained EC50 values ranged from 0.12 to 0.37 mg/mL of solution. The ABTS radical scavenging activity ranged from 43.20 to 44.53 µg TE/g. The FRAP value was found within the range of 19.48 to 44.74 µmol TE/g of extract. Differences between extraction conditions were observed. In this research, 50 °C/250 bar was efficient for the TPC, DPPH, ABTS, and FRAP assays; moreover, statistically, TPCs and FRAP assay showed significant differences between the conditions at α = 0.05. The identification of phenolic compounds in the obtained extract of Lamium album flowers, using UPLC/PDA, revealed that chrysin, pinostrobin, myricetin, and trans-3-hydroxycinnamic acid were the significant molecules present, which may be responsible for the high content of polyphenols and antioxidant activity. The results obtained indicated that SC-CO2 could be considered an alternative method for extracting bioactive compounds of Lamium album. High antioxidant activity and the presence of various bioactive compounds indicate the potential of this plant from the Lamiaceae family and the possibility of its application in various industries, including agriculture, food technology, or pharmacy.

Antioxidants remain interesting molecules of choice for suppression of the toxic effects of free radicals in foods and human systems. The current practice involves the use of mainly synthetic molecules as potent antioxidant agents. However, due to the potential negative impact on human health, there is an intensive effort within the research community to develop natural alternatives with similar antioxidant efficacy but without the negative side effects of synthetic molecules. Still, the successful development of new molecules depends on the use of reliable chemical or cell culture assays to screen antioxidant properties. Chemical antioxidant assays include the determination of scavenging ability against free radicals such as DPPH, superoxide anion radicals, hydroxyl radicals, hydrogen peroxide, and nitric oxide. Other antioxidant tests include the ability of compounds to bind and sequester prooxidant metal cations, reduce ferric iron, and attenuate the rate of lipid oxidation. Ex vivo tests utilize cell cultures to confirm entry of the molecules into cells and the ability to quench synthetic intracellular free radicals or to stimulate the increased biosynthesis of endogenous antioxidants. In order to assist researchers in their choice of antioxidant evaluation methods, this review presents background scientific information on some of the most commonly used antioxidant assays with a comparative discussion of the relevance of published literature data to food science and human nutrition applications.

European beech (Fagus sylvatica L.) is a deciduous tree, widely distributed in Europe and largely appreciated for its wood and nutritive nuts. Beech leaf also enjoys food use as salad, but an understanding of its nutraceutical value is still far from being achieved. Indeed, and also taking into account beech leaf as a consistent biomass residue available beechwood production and use, it needs to be explored as a valuable renewable specialized source of bioactive molecules. In this context, an untargeted ultra-high-performance liquid chromatography hyphenated with high resolution mass spectrometry (UHPLC-HRMS) approach was favorably applied to a beech leaf alcoholic extract, which also was evaluated for its antiradical capability (by means of assays based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and [2,2’-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid)] (ABTS) radical cation) and its ferric ion reducing power. Redox mitochondrial activity towards Caco-2 cells paved the way to explore the extract’s capability to inhibit intracellular Reactive Oxygen Species (ROS) using 2’,7’dichlorofluorescin diacetate (DCFH-DA) assay. Hydroxycinnamoyl derivatives, mainly belonging to the chlorogenic acid class, and flavonoids were the main constituents. Uncommon flavanone C-glycosides were also found, together with a plentiful flavonol diversity. Cell-free and cell-based assays highlight its dose-dependent antioxidant efficacy, providing a foundation for further investigation of beech leaf constituents and its valorization and use as a reservoir of bioactive natural products with potential nutraceutical applications.

Six critical stages corresponding to major morphophysiological events in carob fruit ripening were defined, and changes in the primary and secondary metabolome and in vitro antioxidant capacity were examined in two genotypes collected at low (15 m) and high (510 m) altitudes from genetically identified and georeferenced trees. Soluble carbohydrates were analyzed by HPLC-RI, macro-minerals by ion chromatography coupled to conductivity detection and polyphenols by UHPLC-Q-Orbitrap-HRMS. spectroscopy facilitated assays for condensed tannins and in vitro free-radical scavenging capacity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP). The fruit respiration rate and moisture content declined sharply during the transition from the breaker to green pedicel stage. Sugar accumulation spiked at the onset of fruit coloration and culminated at 498.7 ± 8.4 mg g−1 dry weight (dw) in the late ripe stage, while the ratio of reducing sugars to sucrose decreased from 3.45 ± 0.32 to 0.41 ± 0.02. The total phenolic compounds and condensed tannins declined with ripening, particularly during the transition from the breaker to green pedicel stage. Eighteen polyphenols were identified and quantitated, with catechins and hydrolyzable tannins being dominant until the onset of fruit coloration. The transition to the green pedicel stage signaled a precipitous decline (90.9%) in catechins, hydrolyzable tannins (60.2%) and flavonol glycosides (52.1%) concomitant to the rise in gallic acid, which was putatively fueled by the enzymatic hydrolysis of gallotannins in immature fruit. Catechins, hydrolyzable tannins and flavone glycosides were more abundant at higher altitudes and gallic acid at lower altitudes. An antioxidant capacity was also favored by higher elevations and declined with ripening, particularly after the breaker stage. Correlations with FRAP and DPPH assays were significant for the total phenolic content, condensed tannins, catechins and hydrolyzable tannins. The highest correlation factors were obtained for epigallocatechin-gallate (r = 0.920 and r = 0.900; p < 0.01). Although the sharp drop in hydrolyzable and nonhydrolyzable tannins and catechins compromised the in vitro antioxidant capacity at physiological maturity, it also reduced the astringency and configured a palatable organoleptic fruit profile. These changes unraveled significant episodes in the ripening-related secondary metabolism of the carob fruit. They further highlighted the value of immature carob as a potent source of gallotannins, with putative in vivo anti-inflammatory action, and of catechins beneficial in preventing and protecting against diseases caused by oxidative stress.

In the present work we synthesized a selected series of hydroxylated 3-phenylcoumarins 5–8, with the aim of evaluating in detail their antioxidant properties. From an in depth study of the antioxidant capacity data (ORAC-FL, ESR, CV and ROS inhibition) it was concluded that these derivatives are very good antioxidants, with very interesting profiles in all the performed assays. The study of the effect of the number and position of the hydroxyl groups on the antioxidant activity was the principal aim of this study. In particular, 7-hydroxy-3-(3'-hydroxy)phenylcoumarin (8) proved to be the most active and effective antioxidant of the selected series in four of the performed assays (ORAC-FL = 11.8, capacity of scavenging hydroxyl radicals = 54%, Trolox index = 2.33 and AI30 index = 0.18). However, the presence of two hydroxyl groups on this molecule did not increase greatly the activity profile. Theoretical evaluation of ADME properties of all the derivatives was also carried out. All the compounds can act as potential candidates for preventing or minimizing the free radical overproduction in oxidative-stress related diseases. These preliminary findings encourage us to perform a future structural optimization of this family of compounds.

Recently, the interest in discovering natural antioxidants has increased tremendously for their application to control onset of multiple diseases. The present study was designed to determine polyphenolic compounds and antioxidant potential of Hedera nepalensis. Crude extract of H. nepalensis and its fractions (n-hexane, ethyl acetate and aqueous) was prepared by solvent–solvent extraction. Total flavonoid and phenolic contents were determined by colorimetric methods using quercetin and gallic acid as standard. Further quantitative analysis of phenolic and flavonoid compounds was carried out by using high performance liquid chromatography coupled with diode array detector (HPLC-DAD). Ethyl acetate fraction showed the highest amount of total flavonoid (2.4 ± 0.164 mg QE/100 mg) and phenolic contents (12.90 ± 0.15 mg GAE/100 mg). Using HPLC-DAD, catechin was identified in aqueous fraction and caffeic acid was identified in ethyl acetate fraction of H. nepalensis. The antioxidant capacity of H. nepalensis was evaluated by measuring the scavenging potential of hydrogen peroxide (H2O2), total antioxidant capacity and reducing power. The extract/fractions showed significant (P

Coffee is a major source of dietary antioxidants; some are present in the green bean, whereas others are generated during roasting. However, there is no single accepted analytical method for their routine determination. This paper describes the adaption of three complementary assays (Folin-Ciocalteu (FC), ABTS and ORAC) for the routine assessment of antioxidant capacity of beverages, their validation, and use for determining the antioxidant capacities of extracts from coffee beans at different stages in the roasting process. All assays showed a progressive increase in antioxidant capacity during roasting to a light roast state, consistent with the production of melanoidins having a higher antioxidant effect than the degradation of CGAs. However, the three assays gave different numbers for the total antioxidant capacity of green beans relative to gallic acid (GA), although the range of values was much smaller when chlorogenic acid (CGA) was used as reference. Therefore, although all three assays indicated that there was an increase in antioxidant activity during coffee roasting, and the large differences in responses to GA and CGA illustrate their different sensitivities to different types of antioxidant molecule.

The efficiency of the chemiluminescence luminol method and colorimetric DPPH and ABTS methods in evaluating the antiradical capacity of pure compounds and plant extracts with antioxidant potential is compared. In case of pure compounds, the values of parameter 'n' (number of radicals quenched per molecule of antiradical) for ascorbic acid, p-hydroquinone, catechol, quercetin, and rutin are similar when measured by colorimetric assays; however, considerably lower values of n are obtained with the luminol assay. The antiradical activity of extracts from male and female individuals of Baccharis burchelli and Baccharis crispa were determined by the luminol assay and expressed using the new Trolox® percentage (%Trolox®) parameter.

The aim of this study was to evaluate the antibacterial and antioxidant activities of essential oil from Chenopodium ambrosioides L. and to determine its secretory structures. The essential oil was extracted through the hydrodistillation technique using a modified Clevenger apparatus (2 hours) and chemically characterized by GC/MS and GC-FID. The antioxidant activity was determined by monitoring the reduction of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and by the oxidation of the β-carotene/linoleic acid system. The evaluation of antibacterial activity was performed by the agar cavity diffusion technique using the microorganisms Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella Cholerasuis. The characterization of trichomes was accomplished by Scanning Electron Microscopy (SEM) and histochemical tests with Nadi and Sudan IV reagents. The antioxidant activity demonstrated by the β-carotene/acid linoleic test, with IC50 = 455.7 µg mL-1. This oil also presented antibacterial activity for both Gram-negative and Gram-positive bacteria. The minimal inhibitory concentration ranged 62.5 to 250 µL mL-1. The presence of terpenes in the glandular trichomes was observed, suggesting that the essential oil is secreted by these structures.

In the present work the antioxidant activity of different solvent (100% methanol, 80% methanol, 100% acetone, 80% acetone) extracts of rice bran was evaluated following different antioxidant assays and using sunflower oil as oxidation substrate. The rice bran extracts were evaluated from the estimate of % inhibition of peroxidation in linoleic acid system, total phenolics content (TPC) and loss of β-carotene in a linoleic acid system. Additionally, crude concentrated rice bran extracts were added into the sunflower oil samples and stored under ambient conditions. The extent of oxidative deterioration was followed by the measurement of peroxide-, p-anisidine-, conjugated diene-, and triene- values. The general order of antioxidant efficacy of rice bran extracts as determined by various antioxidant assays was 80% methanolic extract > 100% methanolic extract > 80% acetone extract > 100% acetone extract. The results of the present comprehensive analysis demonstrate that rice bran extracts of the Super Kernel variety indigenous to Pakistan are a viable source of natural antioxidants and might be exploited for functional foods and nutraceutical applications.