Excellent Radical Scavenging Activity Research Articles

The proteomic evidence on protein oxidation in pea protein concentrate-based low-moisture extrudates and its inhibition by antioxidants derived from plant extracts

This study aimed to assess the antioxidant activity of golden chlorella (GoC) and grape pomace (GrP) extracts both in vitro and in pea protein-based extrudates. We hypothesized that GoC/GrP would limit oxidation of proteins in the extrudates compared with commercial antioxidants. The results showed that GoC extract was effective in metal chelation and GrP extract possessed excellent radical scavenging activity and reducing power. Protein oxidation inevitably occurred after low-moisture extrusion in terms of elevated level of protein carbonyls and the gradual loss of thiols. LC-MS/MS revealed that the monoxidation and 4-hydroxynonenal adduction were the major oxidative modifications, and legumin was the most susceptible globulin for oxidation. The GoC/GrP extracts effectively retarded the oxidation progress in extrudates by lower intensity of oxidized peptides, whereas protein electrophoretic profiles remained unaffected. This study highlighted the great potential of GoC/GrP as natural antioxidants in plant-based foods.

One-Step to Prepare Lignin Based Fluorescent Nanoparticles with Excellent Radical Scavenging Activity

One-Step to Prepare Lignin Based Fluorescent Nanoparticles with Excellent Radical Scavenging Activity

Biodegradable polymer‐based hydrogel as a bioactive carrier for dermatological cosmetics and pharmaceutical applications

AbstractA novel biodegradable interpenetrating polymer network hydrogel impregnated with a plant extract was designed using a simple one‐pot free radical polymerization of polyacrylamide (PAM), poly(vinyl alcohol) (PVA) and gelatin (Gel). PAM/PVA/Gel hydrogels with different Gel contents (Gel‐0–Gel‐40) reached a maximum water absorbency of 1443%, which was approximately three times greater than PAM hydrogel. Biocompatibility assessment of all hydrogels on L929 fibroblast cells demonstrated no toxicity. Gel‐10 hydrogel with a water absorbency of 1120% presented the optimal tensile strength of 363 kPa. The compressive modulus of Gel‐10 hydrogel was 36.2 kPa with the ability to maintain shape under load. Gel‐10 hydrogel demonstrated a good adhesive property on various surfaces including paper, glass, aluminium and skin. A release study revealed a sustained release characteristic which involved Fickian diffusion. A plant extract, Quercus infectoria (Qi), was successfully impregnated as a bioactive agent into Gel‐10 hydrogel and demonstrated a broad spectrum of antibacterial activity against both Gram‐positive and Gram‐negative bacteria. In addition, the Qi‐impregnated hydrogel possesses an excellent radical scavenging activity with 94.6% inhibition and antityrosinase activity with 88.4% inhibition. Studies on biodegradation in soil indicated that the external surfaces of Gel‐10 hydrogel were destroyed. The percentage weight loss of Gel‐10 hydrogel was 66.7%. Additionally, the water absorbency of Gel‐10 after a soil burial test was significantly decreased (421%), compared with 1120% before the test (P < 0.001). Gel‐10 hydrogel could be applied as a bioactive carrier in dermatological cosmetics and pharmaceutical products to prevent infections, deleterious effects from free radicals, and skin pigmentation disorders. © 2023 Society of Industrial Chemistry.

Evaluation of Photocatalytic, Antioxidant, and Antibacterial Efficacy of Almond Oil Capped Zinc Oxide Nanoparticles.

In this study, ZnO nanoparticles (NPs) were synthesized in the presence of almond oil at various molar ratios of zinc acetate and sodium hydroxide, including 0.5:1, 0.75:1, 1:1, 1.25:1, and 1.5:1, to obtain pH values of 11, 10, 9, 8, and 7, respectively. The XRD results revealed that ZnO NPs exhibit a hexagonal structure, with high crystallinity. SEM results showed that dense and large sized ZnO NPs were formed at pH 11, and relatively small (~30-40 nm) NPs were obtained at pH 9. The size distribution can be explained in terms of the presence of OH- ions at different pH levels. However, the larger size of the NPs at pH 7 compared to those at pH 8-11 were due to the coalescence of NPs suitable for antioxidant/antibacterial activities. ZnO NPs demonstrated a high degradation efficiency (~93%) in 90 min, with a high rate constant for Methyl Orange (MO), which is better than the previously reported rate. The larger sized almond oil capped ZnO NPs also showed excellent radical scavenging activity (94%) and are proven to be good carriers to resist Escherichia coli (E. coli) bacteria.

Phytochemical profiling of Symplocos tanakana Nakai and S. sawafutagi Nagam. leaf and identification of their antioxidant and anti-diabetic potential

Symplocos sp. contains various phytochemicals and is used as a folk remedy for treatment of diseases such as enteritis, malaria, and leprosy. In this study, we discovered that 70% ethanol extracts of Symplocos sawafutagi Nagam. and S. tanakana Nakai leaves have antioxidant and anti-diabetic effects. The components in the extracts were profiled using high-performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry; quercetin-3-O-(6′′-O-galloyl)-β-d-galactopyranoside (6) and tellimagrandin II (7) were the main phenolic compounds. They acted as strong antioxidants with excellent radical scavenging activity and as inhibitors of non-enzymatic advanced glycation end-products (AGEs) formation. Mass fragmentation analysis demonstrated that compounds 6 and 7 could form mono- or di-methylglyoxal adducts via reaction with methylglyoxal, which is a reactive carbonyl intermediate and an important precursor of AGEs. In addition, compound 7 effectively inhibited the binding between AGE2 and receptor for AGEs as well as the activity of α-glucosidase. Enzyme kinetic study revealed that compound 7 acts as a competitive inhibitor of α-glucosidase, through interaction with the active site of the enzyme. Therefore, compounds 6 and 7, the major constituents of S. sawafutagi and S. tanakana leaves, are promising for developing drugs for preventing or treating diseases caused by aging and excessive sugar consumption.

Ni2+, Pt4+, Pd2+, and Mn2+ Metal ions Complexes with Azo Derived from Quinolin-2-ol and 3-amino-N-(5-methylisoxazol-3-yl) Benzenesulfonamide: Synthesis, Characterization, Thermal Study ,and Antioxidant Activity

Diazotization reaction between quinolin-2-ol and (2-chloro-1-(4-(N-(5-methylisoxazol-3-yl)sulfamoyl)phenyl)-2l4-diazyn-1-ium was carried out resulting in ligand-HL, this in turn reacted with the next metal ions (Ni2+, Pt4+, Pd2+, and Mn2+) forming stable complexes with unique geometries such as (tetrahedral for both Ni2+ and Mn2+, octahedral for Pt4+ and square planer for Pd2+ ). The creation of such complexes was detected by employing spectroscopic means involving ultraviolet-visible which proved the obtained geometries, fourier transfer proved the formation of azo group and the coordination with metal ion through it. Pyrolysis (TGA & DSC) studies proved the coordination of water residues with metal ions inside the coordination sphere as well as chlorine atoms. Moreover, element micro-analysis and AAS that gave corresponding outcome with theoretically counting outcome. (1H &13C-NMR) and magnetic quantifications can also indicate the formation of ligand-HL and occurrence of coordination. Antioxidant activities of these compounds were evaluated against (DPPH) radical and were compared to the standard natural antioxidant, ascorbic acid. The findings showed that these compounds exhibit excellent radical scavenging activities

Synthetic Access to Bis(pyrazolyl)methanes using cost‐efficient Triethylammonium Hydrogen Sulfate Ionic Liquid: Evaluation of Antioxidant Activity via in silico and in vitro Studies

AbstractA highly efficient, facile and greener approach has been developed for the synthesis of bis(pyrazolyl)methanes. The method involves a reaction of 3‐methyl‐1‐phenyl‐2‐pyrazoline‐5‐one and substituted aromatic/heterocyclic aldehydes at ambient reaction conditions using ionic‐liquid, triethylammonium hydrogen sulfate to yield desired bis(pyrazolyl)methanes in excellent yields (85–96 %). The significant aspect of this protocol is the use of ionic liquid as a replacement of toxic and expensive metal catalysts thereby reducing the production of harmful chemical wastes and avoiding the use of toxic and volatile reagents in the synthesis. The catalyst was easily separated and reused up‐to five runs without significant decrease in its catalytic activity. Molecular docking studies were conducted on Cytochrome P450 3 A4, methylenetetrahydrofolate reductase, and tumor protein to predict their utility as potential anti‐oxidant, and anti‐cancer compounds. The outcome indicates that these synthesized compounds have the scaffold that binds well in the hydrophobic‐pocket of the respective enzyme and the polar groups present in their scaffold form hydrogen‐bonding too. Furthermore, we infer from the docking calculations that, all were docked in the binding domain of 4D75, eleven were docked in the active site of 6FCX and nine compounds were docked within the binding site of 3S7S. Furthermore, the in‐vitro antioxidant activity of synthesized compounds was explored against DPPH and ABTS, and most of the compounds were found to have high to excellent radical scavenging activity.

Effects of carboxyl- and amino-groups on the antioxidant activity of hydroxyanthraquinones with ESIPT property: A theoretical study

Although anthraquinones have aroused great scientific interest due to their excellent radical scavenging activities, there is seldom systematic theoretical research about their antioxidant mechanisms. Herein, the effect of electron-withdrawing and donating substituents (–COOH and –NH2) on the antioxidant activity of 1,8-Dihydroxyanthraquinone (DHAQ) and its structural analogues (DHAQ-COOH, DHAQ-2COOH, DHAQ-NH2, and DHAQ-2NH2) in acetonitrile (ACN) has been comprehensively studied using quantum chemistry methods. The significant parameters associated with three primary antioxidant mechanisms were unveiled. Besides, the constructed potential energy curves (PECs) were scanned, which have not only proved that the forward proton transfer processes are merely available in the excited state, but also directly confirm the possible stable configurations in the excited state. Subsequently, the ESIPT-antioxidant activity relationship has been established and based on which DHAQ-COOH was judged to be the most promising free radical scavenger upon the photoexcitation.

Engineered baicalein-decorated zinc phosphates for synergistic alleviation of inflammatory bowel disease by repairing the mucosal barrier and relieving oxidative stress.

Orally administered baicalein-decorated zinc phosphates (ZnBM) were engineered for mucosal barrier improvement and intestinal inflammation relief. ZnBM with a size of 1.78 μm comprised 5.58 wt% baicalein and 13.17 wt% zinc. The incorporation of baicalein endowed ZnBM with excellent radical scavenging activities. ZnBM exhibited good stability with negligible zinc release in PBS solution for 2 days, and 32.82% of the zinc could reach the gut. In addition, ZnBM polarized macrophages into the anti-inflammatory M2 type and effectively scavenged intracellular reactive oxygen species (ROS) of lipopolysaccharide (LPS)-treated RAW264.7. Meanwhile, ZnBM effectively scavenged intracellular ROS of phorbol 12-myristate 13-acetate (PMA)-induced Caco-2 cells and exerted a reparative effect on the LPS-damaged Caco-2 monolayer, causing an obvious improvement of the barrier function. Reduced systemic exposure to FITC-dextran was observed to illustrate barrier restoration by ZnBM, which was achieved through upregulation of tight junction protein expression. Notably, the commonly used clinical drug 5-aminosalicylic acid is toxic to the liver and kidneys, and commercial ZnO caused the death of mice during treatment. Apparently, the therapeutic effect of ZnBM was significantly better than that of baicalein alone in chronic colitis. Overall, ZnBM exhibited outstanding therapeutic efficacy and is expected to treat colitis due to its effectiveness, biosecurity, facile preparation, and easy storage.

Biological screening of Pleurostylia opposita (Wall.) Alston. – a rare medicinal plant of Eastern Ghat

The present study aims to evaluate the phytochemical, antioxidant and antibacterial properties in Pleurostylia opposita in various solvent crude extracts of leaf and bark. Preliminary phytochemical and antibacterial screening by well diffusion method was conducted. Further, total phenolic, and flavonoid contents estimation along with antioxidants properties by DPPH method was carried out in various solvent extracts. The phytochemical study revealed that the maximum secondary metabolites such as alkaloids, polyphenols, sterols, terpenoids flavonoids, and saponins were present in methanol extracts followed by other extracts. Likewise, antibacterial screening showed the maximum growth of inhibition in methanol leaf and bark extracts against E. coli (23mm), Salmonella typhi (23mm), Bacillus subtilis (24mm), Staphylococcus aureus (19mm), and Pseudomonas aeroginosa (24mm). The minimum inhibitory concentrations of the leaf and bark extracts were in the range of 19.5 mg/L - 625mg/L while gentamycin is 9.75mcg/L. The results indicate that the methanol extracts of leaf and bark showed potent antibacterial efficacy. Further, the antioxidant activity by DPPH assay indicates, that all the extracts exhibited significant antioxidant properties in a dose-dependent manner. Among the tested extracts, methanol exhibited excellent radical scavenging activity which was significant compared to Gallic acid. Likewise, each extract also showed excellent sources of phenolic and flavonoid contents. This study reveals that the plant contains a considerable amount of phenols and flavonoids, including antioxidant properties which are also possessing antibacterial efficacy. This study offered a new avenue for the potential use of this species as a source of natural antioxidants.

In vitro digestibility of proteins, peptidomic analysis and antioxidant ability of sodium-reduced pork sausage with partial substitution of NaCl by KCl

High salt (NaCl) consumption can impact on human health, and KCl is the most widely used replacement salt in meat products. This study investigated the effects of 0% NaCl (NS), 3% NaCl (HS), 1.95% NaCl (RS), 1.95% NaCl+1.05% KCl (RS + K) on protein digestibility of pork sausage in vitro. The results indicated that RS + K showed the highest gastrointestinal digestibility (GID) because of the structure of looser cross-linked strands and uniform cavities, while HS exhibited the lowest GID. RS + K released more peptides (2499) during gastrointestinal than NS (2301), RS (2130) and HS (2235), with a higher proportion of peptides with molecular weights <1000 Da, and more unique peptides. Meanwhile, the digestion product of RS + K exhibited excellent radical scavenging activity and improved the antioxidant abilities to reduce oxidative injury which was induced by H2O2 in HepG2 cells. These results demonstrated that partial substitution with KCl can be an effective strategy for improving the digestibility of sodium-reduced gel-type meat products.

Dietary nutrients in edible mushroom, Agaricus bisporus and their radical scavenging, antibacterial, and antifungal effects

The present study aims to explore the dietary nutrient levels of the edible mushroom, A. bisporus by biochemical analysis and evaluated their medicinal value in treating the human pathogenic microorganisms and free radical scavenging effects. A. bisporus mushroom exhibits a high amount of carbohydrates (41.6 ± 0.66 %) and crude proteins (39.84 ± 0.66 %). The crude fibre (8.6 ± 0.42 %), ash (8.23 ± 0.44 %), nitrogen (protein) contents (9.1 ± 0.44 %) were available at a significant level and also possessed a lesser amount of fat (1.73 ± 0.33 %). The quantitative determination of mycochemicals in A. bisporus reveals the presence of flavonoids (0.783 ± 0.03 g/100 g), phenolic content (0.441 ± 0.01 g/100 g), free amino acids (0.128 ± 0.12 g/100 g), saponin (0.121 ± 0.01 g/100 g), alkaloids (0.034 ± 0.01 g/100 g), tannins (0.027 ± 0.03 g/100 g) and vitamin C (12.8 ± 0.33 mg/g). Flame photometer and Inductivity Coupled Plasma Optical Emission Spectrometry (ICP-OES) study reveals the presence of minerals viz., potassium (2925.14 ± 0.67 mg/100 g), phosphorus (1230 ± 0.67 mg/100 g), magnesium (115.05 ± 0.24 mg/100 g) and calcium (107.21 ± 0.34 mg/100 g) in A. bisporus mushroom. Moreover, the Fourier transform infrared (FTIR) spectrum established the presence of possible biomolecules in A. bisporus mushroom. A greater antimicrobial effect against Staphylococcus aureus (14.3 ± 0.24 mm) and Candida albicans (14.2 ± 0.12 mm) was observed compared to Streptococcus pyogenes (10.8 ± 0.12 mm), Shigella flexneri (10.8 ± 0.21 mm), Klebsiella pneumoniae (11.1 ± 0.33 mm) and Aspergillus fumigatus (11.2 ± 0.33 mm). The mushroom extract of A. bisporus have an excellent radical scavenging activity with an IC50 of 12.5 µg/mL against 1,1-diphenyl-2-picrylhydrazyl (DPPH). This investigation revealed that A. bisporus mushroom has great potential to be used as food supplement to fight against pathogens in the near future.

DTP/SiO2 Assisted Synthesis of New Benzimidazole-Thiazole Conjugates Targeting Antitubercular and Antioxidant Activities

A series of new substituted benzimidazole-thiazoles (9a–l) have been designed and synthesized using 2-aminothiazole as a starting material by using molecular hybridization approach. The newly synthesized compounds were characterized by 1H NMR, 13C NMR and HRMS analyses. The compounds (9a–l) were evaluated for their in vitro antitubercular activity against Mtb (MTCC 300) strain. Among the screened compounds 9a, 9b, 9c and 9d have displayed promising antitubercular activity with MIC 7.55, 4.60, 15.39 and 28.38 μg/mL, respectively. All the compounds were further evaluated for their DPPH radical scavenging activity. The compounds 9a, 9b and 9d were exhibited excellent radical scavenging activity. In addition to this, single crystal structure of compound 9a was also studied. Furthermore, the high potency of these molecules was supported by ADME properties prediction as well as molecular docking study to gain an insight into the binding mode and affinity toward mycobacterial InhA.

Highly-toughened PVA/nanocellulose hydrogels with anti-oxidative and antibacterial properties triggered by lignin-Ag nanoparticles

In this study, Ag nanoparticles were firstly reduced on the surface of lignin nanoparticles (LNPAg) by direct reaction of silver nitrate without the use of a catalyst. Thermogravimetric analysis, Zeta potential and transmission electron microscopy measurements were performed to give evidence of the effectiveness of the reaction. After that, glutaraldehyde crosslinked PVA hydrogels, were produced by addition of unmodified LNP and Ag loaded LNP (LNPAg) in presence of cellulose nanocrystals (CNC). Thermal, mechanical, rheological, microstructural and biological anti-oxidative and anti-bacterial properties of the resulted hydrogels were investigated. It was proved that all the three nanofillers were homogeneously dispersed in PVA, and the pore diameter of the hydrogels was in the range of 0.5–2.0 μm. Nevertheless, the hydrogels showed high toughness, long-term and repeatable adhesiveness to a variety of substrates. In particular, composite hydrogels containing LNPAg nanoparticles showed excellent radical scavenging and antibacterial activities. Consequently, the effects of PVA-2CNC-2LNPAg on wound healing in mice model of full-thickness skin resection were evaluated by hematoxylin and eosin staining, taking as a reference the PVA-2CNC-2LNP system. The results showed that the wound healing time of PVA-2CNC-2LNPAg group was faster than that of neat PVA and PVA-2CNC, highlighting the role of LNPAg in enhancing the contact-active anti-oxidative and antibacterial activities mechanism in composite hydrogels. We expected that PVA hydrogels incorporating LNPAg could be used as green and efficient biomedical wound dressing materials.

The evaluation of the anti-Histone deacetylase, antibacterial, antioxidant and cytotoxic activities of synthetic N,N´-ethylenebis(α methylsalicylideneiminate) Schiff base derivatives

Recently, Schiff base complexes as synthetic antioxidants are widely used instead of natural antioxidants because they are effective and cheaper. In this study, a series of α,ά-Me2-salen, (N,N´-ethylenebis(α methylsalicylideneiminate)) Schiff base derivatives have been investigated toward their anti-histone deacetylase (HDAC), anticancer, antibacterial and antioxidant activities. For anti HDAC studies, AUTODOCK 4.1 and Molecular Dynamics (MD) simulation have been conducted against these combinations. Cytotoxic test, ferric reducing ability of plasma (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) ABTS assays and Agar diffusion method have been applied to investigate anticancer, antioxidant and antibacterial activities, respectively. Based on the results, the best docking was obtained for α,ά-Me2-salen against HDAC. Also, MD calculation results demonstrated that the α,ά-Me2-salen is more effective compound for HDAC inhibiting than SAHA as a known enzyme inhibitor. However, α,ά-Me2-salen and its derivatives didn't display antibacterial activity against any of the microorganisms. Cytotoxic activity analysis toward MCF 7 cell line were apparent that α,ά-Me2-salen and its Ni (II), Co (II), and Cu (II) derivatives manifested high cytotoxic activity with IC50 5, 2, 2 and 3 µg ml−1, respectively. The antioxidant results were revealed excellent radical scavenging activities of all these compounds against DPPH, ABTS and FRAP radicals. The antioxidant activity by DPPH, showed Mn(II) complex (IC50 = 0.13 ± 0.50 mg/ml) was the most active. While, α,ά-Me2-salen (IC50 =0.05±0.003 mg/ml) and its Ni(II) derivative (IC50 =0.049 mg/ml) exhibited the highest ABTS scavenging activity. According to results, all compounds show acceptable anticancer and antioxidant activity and can be used as drug candidates after further investigations.

Structural characterization and antioxidant activity of alkali-extracted polysaccharides from quinoa

A polysaccharide component (SQAP-2) was isolated from quinoa by alkaline extraction and purified with DEAE-Sepharose Fast Flow and Sephacryl S-300 column chromatography. The chemical structure of the polysaccharide was characterized, and the impact on antioxidant activity was evaluated. Polysaccharide SQAP-2 (2.02 × 103 Da) is a type of glucose whose glycosidic bond Glc-(1→, →4)-Glcp-(1→, →4, 6)-Glcp-(1→ linkages were identified through gas chromatography-mass spectrometry. Nuclear magnetic resonance confirmed the monosaccharide composition and glycosidic linkage content, and a suggestion of the structural formula was provided. Their radical scavenging capacity was evaluated, and scavenging activity against DPPH, ABTS, hydroxyl, superoxide radicals, and ferric reducing ability exhibited excellent radical scavenging activities of approximately 21.71 ± 1.25%, 49.46 ± 1.59%, 70.10 ± 3.39%, 70.49 ± 2.09%, 51.25 ± 1.16%, respectively, at 3 mg/mL. The isolated quinoa polysaccharides could represent an antioxidant agent once the structural features and antioxidant activities are definitively characterized.

Development of a Gemini Interfacial Antioxidant for Oil in Water Emulsion with Gallic Acid and Dodecyl Gemini Chains.

In this study, development of the gemini gallate (GG) interfacial antioxidant for oil in water (O/W) emulsion was performed employing Steglich esterification with gallic acid and dodecyl gemini chains through a prepacked column and peristaltic pump-based purification system. The structural identity and purity of the prepared GG and monogallate (MG) were confirmed by NMR, Fourier transform infrared spectroscopy, and high-performance liquid chromatography-mass spectrometry. Further evaluation revealed that the GG possessed excellent radical scavenging activity and superior antioxidant activity in an O/W emulsion relative to the MG, especially under the condition of a reduced amount of the emulsifier. Microscopic investigation by a fluorescent probe and transmission electron microscopy (TEM) unveiled that the extraordinary antioxidant performance in the O/W emulsion was presumably attributed to preferable interfacial location because of the unique gemini molecular architecture. The superior antioxidant activity of the gemini antioxidant holds great promise for antioxidation in O/W emulsions.

Synthesis, characterization and biological evaluation of novel N-phenoyl phosphatidylethanolamine derivatives

In this study, synthesis of new N-phenoyl phosphatidylethanolamine derivatives was carried out by the modification of natural egg phosphatidylethanolamine (PE) with various phenolic acids. All synthesized products were characterized by NMR, FT-IR and ESI-MS spectral analysis and were evaluated for their preliminary in vitro antioxidant and cytotoxic activities. Among the active derivatives, compounds N-4-hydroxy-3-methoxy cinnamoyl PE, N-4-hydroxy-3,5-dimethoxy cinnamoyl PE and N-(3,4)-di hydroxy cinnamoyl PE were exhibited excellent radical scavenging activity with EC50 values of 9.7, 1.5 and 2.7 µg/mL, respectively which were lower than the standard BHT and α-tocopherols. The synthesized compounds exhibited moderate to very good anticancer activity against four cancer cell lines such as HeLa, B16-F10, SKOV3 and MCF-7 using doxorubicin as a positive control. All the synthesized derivatives may have potential applications in food emulsions and the presence of phenolics has to be examined for additional antioxidant and biological activities.

Pyrazole Derivatives of Medically Relevant Phenolic Acids: Insight into Antioxidative and Anti-LOX Activity.

From the point of view of medicinal chemistry, compounds containing phenolic and pyrazolic moiety are significant since they are often constituents of bioactive compounds. The aims of this study were to synthesize pyrazole derivatives of medically relevant phenolic acids, confirm their structure, and evaluate their antioxidative and anti-LOX activities. Phenolic pyrazole derivatives were obtained, starting from esters of medically relevant phenolic acids. The structures of all obtained compounds were determined by NMR and IR spectroscopy, and UV-Vis spectrophotometry. In addition, the single-crystal X-ray diffraction was used. Pyrazole derivatives were tested for their in vitro antioxidative (DPPH assay), and lipoxygenase (LOX) inhibitory activities. Radical quenching mechanism was estimated using DFT and thermodynamic approach, while molecular docking was used to estimate the binding mode within the enzyme. Pyrazole derivatives were obtained in high yields. The crystal structure of a new compound 3e was determined. Pyrazole derivative with catechol moiety 3d exhibited excellent radical scavenging activity, while compound 3b exhibited the best anti-LOX activity. Molecular docking study revealed that there is no direct interaction of any ligand with the active site of LOX-Ib, but pyrazoles 3a-e behave as inhibitors blocking the approach of linoleic acid to the active site. In this research, protocatechuic and vanillic acid pyrazole derivatives have been obtained for the first time. In vitro antioxidative assay suggests that pyrazole derivate of protocatechuic acid is a powerful radical scavenger, while anti-LOX assay indicates a pyrazole derivative with 4-hydroxyphenyl moiety.

The health benefits of three Hedgenettle herbal teas (Stachys byzantina, Stachys inflata, and Stachys lavandulifolia) - profiling phenolic and antioxidant activities

IntroductionPlants belonging to the genus Stachys have been used in traditional medicine due to their various properties. The potential health benefits of three widely consumed Stachys decoctions (S. byzantina, S. inflate and S. lavandulifolia) were profiled in terms of their phenolic compounds and antioxidant properties, MethodsReverse-phase high-performance liquid chromatography- diode array detector (RP-HPLC-DAD) analysis for phenolics profiling was carried out. Moreover, comprehensive antioxidant ability and several key enzymes inhibitory activity of decoctions were investigated. Results14 phenolic components were quantified in the samples in which chlorogenic acid (6228 μg/g decoction), (+)-catechin (504 μg/g decoction), and rosmarinic acid (460 μg/g decoction) were found to be the major bioactive compounds. S. inflata showed high DPPH radical scavenging potential (141 mg Trolox equivalents/g decoction) and S. byzantina indicated excellent radical scavenging activity in ABTS (330 mg TE/g decoction) assay. Also, all decoctions exhibited strong reducing power in CUPRAC (280−363 mg TE/g decoction) and FRAP (270−312 mg TE/g decoction) assays. Therapeutic enzymes inhibition experiments showed moderate anti-cholinesterase (0.98–1.16 mg galanthamine equivalents/g decoction) and strong anti-tyrosinase (13.6–15.0 mg kojic acid equivalents/g decoction) properties for Stachys herbal teas. ConclusionFindings indicate that the decoction of Stachys species contain important bioactive phenolics and have promising antioxidant effects and health benefits. Thus, these medicinal herbs can be considered as useful ingredients in food and pharmaceutical products.