Antioxidant Activity Of Phenolic Compounds Research Articles

Effect of Side Chain Functional Groups on the DPPH Radical Scavenging Activity of Bisabolane-Type Phenols.

Methods for improving the antioxidant activity of phenolic compounds have been widely investigated; however, most studies have focused on the structure–activity correlations of substituents on the aromatic rings of catechols or flavonoids. We investigated the influence of side chain functional groups on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of xanthorrhizol and curcuphenol analogues. These compounds were synthesised by the side chain functional group conversion of curcumene, followed by direct oxidation of the aromatic ring. We determined the DPPH radical scavenging activity from the half-maximal effective concentration (EC50) obtained from a DPPH assay in methanol. The positional relationships of the side chain with the aromatic ring and phenolic OH group were determined using density functional theory calculations, and the stability of different conformations was compared. Electron transfer-proton transfer was determined to be the dominant mechanism in the DPPH reaction with xanthorrhizol analogues, based on the correlation between the EC50 and ionisation potential. The radical cation was greatly stabilised in the structure where the side chain functional group was close to the aromatic ring. Stabilisation also depended on the phenolic OH group position. In future antioxidant design, aromatic ring substituent conversion and the use of functional groups far from the OH group or ring should be explored.

Bioaccessibility and antioxidant activity of phenolic compounds in cooked pulses

SummaryThe aim of this study was to evaluate the bioaccessibility of polyphenols and antioxidant activity in cooked pulses and to study the effect of cooking on their total phenolic content (TPC) and antioxidant capacity. Cooked faba beans showed the highest TPC, followed by soybeans and lentils or peas. TPC ranged from 10.4 ± 0.2 to 52.9 ± 0.3 mg/100 g and was positively correlated with antioxidant activity. Cooking resulted in increased TPC and antioxidant activity of the methanolic extracts, caused by cell disruption and improved extraction of polyphenols. Although polyphenols were lost in the cooking water, boiled legumes had more polyphenols than those resulting cooking broths. In vitro gastrointestinal digestion resulted in increased TPC and antioxidant capacity of the extracts. Soybeans showed the highest amount of bioaccessible polyphenols. The release of phenolics from cooked legumes was mainly achieved during the intestinal phase. Literature data may underestimate the TPC and antioxidant capacity of pulses.

A comparative study of phenolic compound antioxidant activity by the polarography method, using microsomal lipid peroxidation in vitro

Abstract For comparative purposes, a quantitative estimation of antioxidant activity of phenolic compounds of different classes was conducted by way of the polarography method, via the ADP-Fe2+ model of the induced ascorbate-dependent lipid peroxidation of rat liver micro-somes within an in-vitro system. As a result, it was recognized that the antioxidant properties of phenolic compounds depend on the nature and chemical structure of several substances. In respect of such activity, leaders in the classes of investigated polyphenolic compounds are: Propyl gallate = Gallotannin (Phenolcarboxylic acids and their derivatives) > Quercetin = Myricetin (Flavonols) > Luteolin (Flavo n) = Mangiferin (Xanthones) > Kaempferol (Flavonols) = Catechin (Flavans). Thus, the assessment of the inhibition ability of the lipid peroxidation of microsomes by phenolic compounds can be used as an accessible test for the preliminary quantitative estimation of their antioxidant properties.

A new method for comprehensive utilization of wood vinegar by distillation and liquid−liquid extraction

Abstract To increase the added value and commercialization of wood vinegar (WV), a new method for comprehensive utilization of WV was developed. The primary distillation, liquid–liquid extraction and secondary distillation were used to isolate the different active fractions from WV in the new route. The antioxidant activities of all the fractions were expressed as vitamin C equivalent antioxidant capacities in mg/L using 1, 1-diphenyl-2-picrylhydrazyl scavenging assay, and the antimicrobial activities against Escherichia coli (E. coli) in vitro were represented by the absorbance at a wavelength of 600 nm. The results demonstrated that the isolation of the antioxidants (phenolic compounds) from the residue obtained from primary distillation was satisfactory when the EtOAc/n-hexane (7/3, v/v) was used as extraction solvent and pH value was 4. Acetic acid has inhibition effect on the antioxidant activities of phenolic compounds. The fraction enriched with acetic acid exhibited high antimicrobial activity. Considering the low environmental risk of WV, the findings suggest that WV is potentially useful for the developments of antioxidant and antimicrobial agents in the field of medicine or food preservation and safety.

The role of guaiacyl moiety in free radical scavenging by 3,5-dihydroxy-4-methoxybenzyl alcohol: thermodynamics of 3H+/3e− mechanisms

ABSTRACTParticipation of guaiacyl moiety of 3,5-dihydroxy-4-methoxybenzyl alcohol (DHMBA) in inactivation of free radicals was investigated using the DFT method. The thermodynamics of triple (3H+/3e−) free radical scavenging mechanisms was investigated. The Gibbs free energies of reactions of inactivation of selected 10 free radicals indicate DHMBA as a potent scavenger. Obtained results allow us to suggest that the contribution of guaiacyl moiety to antioxidant activity of phenolic compounds should be taken into account, what has been scarcely considered until now.

Improvement of the Antioxidative Activity of Soluble Phenolic Compounds in Chickpea by Germination.

Our recent study found that antioxidative activity of phenolic compounds extracted from germinated chickpea was boosted in both in vitro assays and oil-in-water emulsions [ Xu et al. Food Chem. 2018 , 250 , 140 ]. The purpose of this study was to elucidate the mechanism by which germination enhances the antioxidative activity of the phenolic compounds extracted from chickpea. Liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS) and size-exclusion chromatography with multiangle-light-scattering and refractive-index detection (SEC-MALS-RI) were employed to evaluate the phenolic composition of soluble phenolic compounds (free and bound) and molar masses of soluble bound phenolic compounds, respectively, over 6 days of germination. According to principal-component analysis of the interrelationship between germination time and phenolic composition, it is revealed that protocatechuic acid 4- O-glucoside and 6-hydroxydaidzein played a pivotal role in the soluble free phenolic compounds, whereas gentisic acid and 7,3',4'-trihydroxyflavone were important in the soluble bound phenolic compounds. Molar masses of soluble bound phenolic compounds were increased after 6 days of germination. Protective and dual antioxidative effects were proposed to explicate how the antioxidative activity of soluble bound phenolic compounds in oil-in-water emulsions was improved with germination.

Chemical composition and antioxidant activity of phenolic compounds and essential oils from Calamintha nepeta L.

Background Essential oils, infusion and decoction extracts of Calamintha nepeta L. were evaluated for their bioactive substances (polyphenols and essential oils) and antioxidant activities. Methods The amounts of phenolic compounds were determined by colorimetric assays and identified by high performance and liquid chromatography coupled with ultraviolet detector (HPLC-UV) method. The chemical composition of essential oils was determined by gas-chromatography coupled with mass spectrometry (GC/MS) method. For the evaluation of the antioxidant activity of essential oils and extracts, two different assays (reducing power and DPPH radical scavenging activity) were used. Results Infusion extract presented the highest phenolic content, followed by the decoction one, while the lowest amount was observed in essential oils. The amount of flavonoids of the decocted extract was higher than that of the infused one. The phenolic profile of C. nepeta infusion and decoction extracts revealed the presence of 28 and 13 peaks, respectively. Four phenolics compounds were identified in infusion (gallic acid (GA), rosmarinic acid (RA), caffeine (C) and caffeic acid (CA)) and two were identified in decoction (GA and RA). The chemical composition of essential oils revealed the presence of 29 compounds, accounting for the 99.7% of the total oils. Major compounds of essential oil (EO) were trans-menthone (50.06%) and pulegone (33.46%). Infusion and decoction extracts revealed an interesting antioxidant activity which correlates positively with their total phenolic contents. Conclusions These results showed that Calamintha nepeta could be considered as a valuable source of phenolics and essential oils with potent antioxidant activity.

Antioxidant activity and Hypolipidemic effect of Ficus carica leaf and twig extracts in Triton WR-1339-induced hyperlipidemic mice

BACKGROUND/AIM: The hypolipidemic potential of both leaf and twig extracts of Ficus carica on experimental hyperlipidaemia induced by Triton WR-1339, in Swiss albino mice was investigated. In addition, the phenolic, flavonoid and anthocyanin contents of these extracts and their antioxidant activities were determined. These properties may have a synergistic effect on hyperlipidaemia. MATERIALS AND METHODS: Leaf and twig samples of F. carica were harvested and collected. The study of antioxidant activity of phenolic compounds was determined by the radical DPPH*, ABTS*+ and FRAP assays. The experimental design was carried out using acute oral toxicity study and Triton model hyperlipidaemia on Swiss albino adult male mice. The animals were observed continuously during the 14 days of the study for any physical signs of toxicity. On the 15th day, the animals were sacrificed by decapitation under anesthesia and the organs were observed for macroscopic pathological lesions. Hyperlipidaemia was induced in the mice by a single intravenous (iv) injection of Triton WR 1339 (300 mg/kg body weight), and the antihyperlipidemic effect of each extract, studied at 150 and 300 mg, was tested by gavage. After 24 hours of administration, serum from blood samples was used to estimate the various parameters of the lipid profile namely TC, TG, LDL and HDL. RESULTS: The results of the phenolic and flavonoid compounds of Ficus carica leaves and twigs varied from 12.84 to 19.78 mg gallic acid equivalents (GAE) and 5.02 to 9.72 mg EQ/g dry matter, respectively. The scavenging activity (IC50) against the radical DPPH* and ABTS*+ varied from 346.2 to 461.38 μg/mL and 288.3 to 369.01 μg/mL for twigs and leaves respectively, and from 50.82 to 54.2 μg/mL for FRAP assay. The acute toxicity study showed no mortality and clinical signs of toxicity in the tested doses. The LD50 value of extracts of twigs and leaves of Ficus carica is greater than 5000 mg/kg. The results revealed that the administration of Ficus carica (FC) leaf and twig extracts resulted in a significant (p < 0.05) decline in levels of serum triglycerides, total cholesterol, LDL-c, and VLDL-c, while the serum high-density lipoprotein cholesterol was significantly increased. The decrease rate of the lipid parameters differs significantly (p < 0.05) from the leaf and twig extracts and depends also on the administered dose. CONCLUSION: Ficus carica leaf and twig extracts may contain compounds able to lower plasma lipid concentrations, could contribute significantly to the total antioxidant properties and be beneficial in the treatment of hyperlipidaemia.

Composition, Distribution, and Antioxidant Activity of Phenolic Compounds in 18 Soybean Cultivars.

Natural phenols are an important functional compound widely distributed in plants with benefits that promote human health. The content of total phenols, flavonoids, and anthocyanins and their composition distribution in 18 soybean cultivars was investigated. There are four phenolic acid distribution forms in these soybean cultivars, namely free, esterified, glycosided, and insoluble-bound. Total phenols, flavonoids, and anthocyanins from 6 black soybean cultivars were found in higher numbers than those from 12 other yellow soybean cultivars. Free and esterified phenolic acids were the main phenolic acid form in all 18 soybean samples. Chlorogenic acid and caffeic acid were the dominant phenolic acids in eight detected phenolic acids, and daidzin and genistin were the abundant isoflavones in five detected isoflavones. Furthermore, the antioxidant activities of total phenols from the 6 black soybean cultivars were greater than those from the 12 yellow soybean cultivars, and there was a significant positive correlation between antioxidant activity and total phenolic content. Black soybeans could be a potential resource for developing natural antioxidants that may play a crucial role in human health protection.

A Comparison of the Chemical Composition, In Vitro Bioaccessibility and Antioxidant Activity of Phenolic Compounds from Rice Bran and Its Dietary Fibres

The composition, in vitro bioaccessibility and antioxidant activities of the phenolic compounds in defatted rice bran (DRB) and its soluble and insoluble dietary fibres were systematically evaluated in this study. The total phenolic content of insoluble dietary fibre from DRB (IDFDRB) was much higher than that of the soluble dietary fibre from DRB (SDFDRB) but was 10% lower than that of DRB. Bound phenolics accounted for more than 90% of the total phenolics in IDFDRB, whereas they accounted for 34.2% and 40.5% of the total phenolics in DRB and SDFDRB, respectively. Additionally, the phenolic profiles and antioxidant activities were significantly different in DRB, SDFDRB and IDFDRB. The phenolic compounds in IDFDRB were much less bioaccessibility than those in DRB and SDFDRB due to the higher proportion of bound phenolics in IDFDRB. Considering that bound phenolics could be released from food matrices by bacterial enzymes in the large intestine and go on to exert significant beneficial health effects in vivo, further studies on IDFDRB are needed to investigate the release of the phenolics from IDFDRB via gut microbiota and the related health benefits.

Pulse seed germination improves antioxidative activity of phenolic compounds in stripped soybean oil-in-water emulsions

The purpose of this study was to investigate antioxidative activity of phenolic compounds extracted from germinated pulse seed including chickpeas, lentils and yellow peas. Phenolic compounds were extracted at different germination time and total phenolic content was examined by Folin Ciocalteu’s reaction. Antioxidative activity of extracts was characterized by in vitro assay including 2, 2-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH), oxygen radical absorbance capacity (ORAC), iron-binding assay, and in stripped soybean oil-in-water emulsions. The results suggested that germination time is critical for phenolic compounds production. The form variation of phenolic compounds influenced the antioxidative activity of phenolic compounds both in vitro assay and in emulsion systems. Soluble bound phenolic compounds showed higher antioxidative ability in emulsion system with the order of chickpea > yellow pea > lentil. On the basis of these results, soluble bound phenolic compounds may be considered as a promising natural antioxidant to prevent lipid oxidation in foods.

Antioxidant, Antiquorum-Sensing and Antibiofilm Activities of <i>Balanites aegyptiaca</i> (L.) Del. (Balanitaceae) and <i>Terminalia macroptera</i> Guill. and Perr. (Combretaceae)

Pseudomonas aeruginosa like many pathogen bacteria produces various virulence factors and form biofilm that contribute to its pathogenicity and the growing resistance to antibiotics. The production of virulence factors in those multi-resistant bacteria is controlled by a mechanism of regulation termed quorum sensing. Interfering with this mechanism of bacterial communication constitute a strategy to attenuate bacterial pathogenicity. Our study aimed to assess the ability of Balanites aegyptiaca and Terminalia macroptera to interfere with the system of QS through inhibition of QS-controlled factors production and the formation of biofilm. Methanol extracts of galls, stem bark of B. aegyptiaca, and stem bark of T. macroptera were screened for anti-QS activity using Chromobacterium violaceum CV026 and P. aeruginosa PAO1. At a sub-inhibitory concentration of 100 µg/mL, galls and stem bark of B. aegyptiaca quenched the QS system by inhibiting violacein production on C. violaceum CV026 and pyocyanin production on P. aeruginosa PAO1. The bark of T. macroptera reduced significantly the production of violacein, pyocyanin and the formation of biofilm. Moreover, antioxidant activity of phenolic compounds contributes to reduce the oxidative stress induced by pyocyanin. Thus, T. macroptera is a potential candidate for the identification and isolation of news effective anti-QS compounds. This study introduces a possible validation for traditional use of B. aegyptiaca and T. macroptera and constitutes a new therapeutic approach for the treatment of infections caused by bacteria resistant to antibiotics.

Effect of Non-Hexane Fraction of Ethanol Extract of Noni Fruit (Morinda citrifolia L.) on ALT Activities, Creatinine Levels and TCD4+/TCD8+ Cell Ratios in The Isoniazid-Induced Female Rats

<p align="center"> Isonicotinyl hydrazine (isoniazid) is the most effective drug for antituberculosis treatment. During the metabolism process of isoniazid, some reactive metabolites might be generated. Thus reactive metabolite possibly responsible for several side effect through the mechanism of oxidative stress. Some of the side effects are liver damage, kidney damage, and autoimmune disorder characterized by decreased TCD4+/TCD8+ cell ratio.</p><pre> Noni (<em>Morinda citrifolia</em> L.) contains phenolic compounds such as scopoletin, quercetin, and rutin, which have various biological activities including antioxidant, antiinflammatory, and hepatoprotective activities. The antioxidant activity of phenolic compounds is through the mechanism of radical scavenging, inhibit formation of free radicals, therefore tissue damage can be prevented.</pre><p>The purpose of this study was to determine chemical constituens of non <em>n</em>-hexane fraction of Noni fruit extract (test sample) and to determine whether test sample can reduce the side effect of isoniazid by measuring ALT activity, creatinine level, and TCD4+/TCD8+ cell ratio. Total 35 <em>Wistar</em> rats, aged 6-8 weeks, were divided into 7 groups. Group I as normal control group received 0.25% DMSO, group II received isoniazid 150 mg/kgBW, group III received ethanol extract of Noni fruit 250 mg/kgBW, group IV received isoniazid 150 mg/kgBW + test sample 15 mg/kgBW, group V received isoniazid 150 mg/kgBW + test sample 30 mg/kgBW, group VI received isoniazid 150 mg/kgBW + test sample 75 mg/kgBW, and group VII received test sample 75 mg/kgBW, each with a volume of 20 mL/kg per oral/day for 8 weeks. Blood samples was collected at weeks 0, 4, 6 and 8 to evaluate the ALT activity, creatinine level, and TCD4+/TCD8+ cell ratio taken. Chemical constituens of test sample was conducted using TLC method.</p>Qualitative analysis indicated that test sample contains alkaloid, phenolic, and flavonoid compound. Test sample could reduce ALT level and increase TCD4+/TCD8+ cell ratio, but couldn’t reduce creatinine level of isoniazide-induced female <em>Wistar</em> rat.

Antioxidant phenolic compounds isolated from wild Pyrus ussuriensis Maxim. fruit peels and leaves

Thirteen phenolic compounds were isolated from pear (Pyrus ussuriensis Maxim.) peels and leaves extracts by using various column chromatography techniques with a guided DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging assay, the result of antioxidant activity of phenolic compounds is then verified by measurement of ROS (reactive oxygen species). The isolated compounds were identified as rutin (1), (−)-catechin (2), orobol (3), daidzein (4), tricin 4′-O-[threo-β-guaiacyl-(7″-O-methyl)-glyceryl] ether (5), tricin 4′-O-[threo-β-guaiacyl-(7″-O-methyl-9″-O-acetyl)-glyceryl] ether (6), 5,7,3′,5′-tetrahydroxyflavanone (7), artselaeroside A (8), trilobatin (9), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (10), quercetin-3-O-(3″-O-galloyl)-α-l-rhamnopyranoside (11), apigenin (12) and quercetin (13) on the basis of nuclear magnetic resonance spectroscopy along with comparison with literature data. Among these compounds, quercetin and quercetin-3-O-(3″-O-galloyl)-α-l-rhamnopyranoside exhibited potent DPPH radical-scavenging activity with IC50 (Half Maximal Inhibitory Concentration) value of 6.06 and 9.60μg/mL, respectively. The results revealed that P. ussuriensis could be used in the fields of food and medicine to prevent human aging diseases.

Adaptive neuro-fuzzy inference system-applied QSAR with bond dissociation energy for antioxidant activities of phenolic compounds.

The aim of this study was to develop quantitative structure-activity relationship (QSAR) models for predicting antioxidant activities of phenolic compounds. The bond dissociation energy of O-H bond (BDE) was calculated by semi-empirical quantum chemical methods. As a new parameter for QSAR models, sum of reciprocals of BDE of enol and phenol groups (X BDE ) was calculated. Significant correlations were observed between X BDE and antioxidant activities, and X BDE was introduced as a parameter for developing QSAR models. Linear regression-applied QSAR models and adaptive neuro-fuzzy inference system (ANFIS)-applied QSAR models were developed. QSAR models by both of linear regression and ANFIS achieved high prediction accuracies. Among the developed models, ANFIS-applied models achieved better prediction accuracies than linear regression-applied models. From these results, the proposed parameter of X BDE was confirmed as an appropriate variable for predicting and analysing antioxidant activities of phenolic compounds. Also, the ANFIS could be applied on QSAR models to improve prediction accuracy.

Bioaccessibility and antioxidant activity of phenolic compounds in frozen pulps of Brazilian exotic fruits exposed to simulated gastrointestinal conditions

This study characterized the phenolic profile in siriguela, umbu-cajá and mangaba, as well in their frozen pulps (FPs). The bioaccessibility of phenolic compounds and the antioxidant activity of the FP dialysates were determined following exposure to simulated gastrointestinal conditions. The profile of phenolic compounds identified in fruit and FPs were relatively similar. After pulp processing, increases of 33.60% and 68.72% in free phenolics were observed for mangaba and umbu-cajá, respectively, whereas in siriguela, the free phenolic was reduced by 56.55%. Generally, phenolic levels decreased after exposure to simulated gastric conditions in all FPs. The bioaccessibility of phenolics varied among the evaluated FPs. The highest bioaccessibility was observed for gallic acid in the umbu-cajá FP (73.92%) and the lowest for gentisic acid in the mangaba FP (8.71%). Siriguela and umbu-cajá FP dialysates presented the highest capacity for the capture of the radical 2,2′-diphenyl-2-picrylhydrazyl hydrate, whereas the mangaba FP dialysate demonstrated the highest iron reducing capacity.

Antioxidant activity of phenolic compounds from extracts of Eucalyptus globulus and Melaleuca styphelioides and their protective role on D-glucose-induced hyperglycemic stress and oxalate stress in NRK-49Fcells

Phytochemicals serve as potential therapeutic agents for the prevention and treatment of diseases. In this study, we elucidate the renoprotective activity of compounds isolated from Eucalyptus globulus and Melaleuca styphelioides extracts in glucose- and oxalate-challenged NRK-49F cell model. The antioxidant potential of isolated compounds was evaluated based on their effect on antioxidant enzyme activities and lipid peroxidation levels. The results demonstrated that exposure of NRK-49F cells to glucose and oxalate stress augmented cell damage and attenuated antioxidant enzyme activities. The phytochemicals 2,2,8-trimethyl-6-formyl-chrom-3-ene-7-O-β-D-glucopyranoside, Cornusiin B and tellimagrandin I treatment restored antioxidant enzyme activity, significantly lowered lipid peroxidation levels and effectively protected cells from glucose and oxalate stress equivalent to the known antioxidant, N-acetyl cysteine. Pterocarinin A significantly reversed cellular damage owing to glucose stress. In conclusion, the compounds isolated from E. globulus and M. styphelioides showed potential cytoprotective and anti-oxidative property against glucose- and oxalate-induced oxidative stress in NRK-49F cells.

Determination of antioxidant activity of phenolic compounds of Thymus transcapicus by high performance Liquid Chromatography

Determination of antioxidant activity of phenolic compounds of Thymus transcapicus by high performance Liquid Chromatography

Identification and in vitro antioxidant activities of phenolic compounds isolated from Cynoglossum cheirifolium L.

In an extensive search for bioactive compounds from plant sources, the quantitative and qualitative characterisation of the compounds present in Cynoglossum cheirifolium extracts was studied. Total phenolic and flavonoid contents were determined by spectrophotometric techniques. In vitro antioxidant and radical scavenging profiling was determined through DPPH• scavenging activity and Ferric reducing antioxidant power (FRAP). Our study showed that leaves produce more phenolic compounds, followed by flowering aerial part. The butanolic fraction obtained from leaves extract exhibited the highest total phenolics (78.65 ± 3.58 mg GAE/g DW) and flavonoids (22.15 ± 4.66 mg CE/g DW). In contrast, this fraction displayed the highest DPPH• scavenging ability with IC50 values of 0.06 ± 0.003 mg/mL. The RP-HPLC-PDA analysis of phenolic compounds from leaves of C. cheirifolium lets to identify: rosmarinic acid, ferulic acid, caffeic acid, p-coumaric acid, syringic acid, sinapic acid and rutin. The obtained results indicate that this plant represent a valuable source of natural antioxidants.

Antioxidant activity of polyphenols from larch wood: an amperometric study

PurposeThe purpose of this paper is to determine the antioxidant activity of natural polyphenols from larch wood by the amperometric method.Design/methodology/approachDirect measurements of antioxidant activity were carried out by the amperometric method in an oxidizing mode with glassy carbon as a working electrode, set potential +1.3V and using a flow-injection system with 2.2 mM phosphoric acid as the mobile phase with a flow rate of 1.2 ml/min.FindingsThe reported results show the following values of antioxidant activity for the tested compounds: (−)-secoisolariciresinol – 0.199 ± 0.002 mg/L (p < 0.05); isolariciresinol – 0.196 ± 0.002 mg/L (p < 0.05); lariciresinol - 0.222 ± 0.001 mg/L (p < 0.05); O-isopropylidene derivative of (−)-secoisolariciresinol - 0.143 ± 0.002 mg/L (p < 0.05); (+)-dihydroquercetin – 0.153 ± 0.002 mg/L (p < 0.05); and quercetin – 0.521 ± 0.001 mg/L (p < 0.05). The last product was tested as the reference of a widely used current antioxidant. General tendencies of determined values of antioxidant activity for studied compounds are in good correlation with published data as determined by the t-BuOOH-initiated lipid peroxidation method.Practical implicationsDescribed results show practical applicability of the amperometric method as being faster and cheaper in comparison to other methods, including oxygen radical absorbance capacity (ORAC) assay or 2,2′diphenyl-1-picrylhydrazyl (DPPH) reagent based assay.Originality/valueThe described results show the first-time application of the amperometric method for the evaluation of the antioxidant activity of phenolic compounds from larch wood.