Total Antioxidant Activity Values Research Articles

Edible flowers efficiency to boost the thermal oxidation stability of soybean oil: Polyphenolic and antioxidant insights

Indigenous people in Bangladesh's Chittagong hill regions use Curcuma longa and Zingiber officinale flowers in their traditional meals due to their vibrant color, exquisite flavor, and fragrant perfume. The induction time of soybean oil enriched with the ethanolic extract of the flower of Curcuma longa (CFE), Zingiber officinale (ZFE), and butylated hydroxytoluene (BHT) was compared to determine the effect on oxidation stability. The study also measured bioactive polyphenolic components, total flavonoid (TFC), total tannin (TTC), total phenolic (TPC), total antioxidant activity (TAA), and IC50 values of ZFE and CFE. The induction time was shorter for both 5 % of CFE (6.97 h) and ZFE (6.85 h) than 0.02 % BHT (7.18 h) but longer than 0.01 % BHT (6.49 h). TPC in CFE (37.57 mg GAE/g) was higher than in ZFE (26.14 mg GAE/g). TAA and IC50 values were not significantly different. TFC in ZFE (28.8 mg QE/g) was higher than in CFE (27.63 mg QE/g). The major polyphenols of CFE and ZFE were trans-cinnamic acid (12,209 and 678 μg/g); catechin hydrate (1758 and 1821 μg/g); p-coumaric acid (1186 and 126 μg/g); and quercetin (1309 and 1773 μg/g), respectively. This study demonstrated that antioxidants in flower extract improve fat and oil oxidation stability.

Combined Strategy Using High Hydrostatic Pressure, Temperature and Enzymatic Hydrolysis for Development of Fibre-Rich Ingredients from Oat and Wheat By-Products

Wheat bran (WB) and oat hull (OH) are two interesting undervalued cereal processing sources rich in total dietary fibre (TDF) and other associated bioactive compounds, such as β-glucans and polyphenols. The aim of this study was to optimise a combination chemical (enzymes) and physical (high hydrostatic pressure-temperature) strategies to increase the bioaccessibility of bioactive compounds naturally bound to the bran and hull outer layers. WB and OH were hydrolysed using food-grade enzymes (UltraFloXL and Viscoferm, for WB and OH, respectively) in combination with HPP at different temperatures (40, 50, 60 and 70 °C) and hydrolysis either before or after HPP. Proximal composition, phytic acid, β-glucans, total phenolics (TPs) and total antioxidant activity (TAC) were evaluated to select the processing conditions for optimal nutritional and bioactive properties of the final ingredients. The application of the hydrolysis step after the HPP treatment resulted in lower phytic acid levels in both matrices (WB and OH). On the other hand, the release of β-glucan was more effective at the highest temperature (70 °C) used during pressurisation. After the treatment, the TP content ranged from 756.47 to 1395.27 µmol GAE 100 g−1 in WB, and OH showed values from 566.91 to 930.45 µmol GAE 100 g−1. An interaction effect between the temperature and hydrolysis timing (applied before or after HPP) was observed in the case of OH. Hydrolysis applied before HPP was more efficient in releasing OH TPs at lower HPP temperatures (40–50 °C); meanwhile, at higher HPP temperatures (60–70 °C), hydrolysis yielded higher TP values when applied after HPP. This effect was not observed in WB, where the hydrolysis was more effective before HPP. The TP results were significantly correlated with the TAC values. The results showed that the application of optimal process conditions (hydrolysis before HPP at 60 or 70 °C for WB; hydrolysis after HPP at 70 °C for OH) can increase the biological value of the final ingredients obtained.

Influence of wood type on anthraquinone levels and quality properties of smoked chipotle pepper

This study aimed to assess the effects of pecan and mesquite wood, as well as smoking time, on anthraquinone (AQ) levels and quality properties of chipotle pepper (CHP) during the traditional smoking process. Changes in moisture content, microstructure, levels of total phenols (TPs), AQ, capsaicin (CAPS), dihydrocapsaicin (DHC), total polyphenols (TPPs), and total antioxidant activity (TAA), as well as color parameters, were measured. A wood mixture consisting of pecan, poplar, mesquite, and pine was used as the control. The CHP moisture content consistently decreased from 12 to 108 h of smoking, with long times exhibiting asymptotic trends across all treatments. Concurrently, structural changes, such as pericarp thinning and plant tissue collapse, were observed as the smoking process progressed. The wood type and processing time had a significant impact (P < 0.05) on TPs, AQ, CAPS, DHC, TAA levels, and color. TPs and AQ exhibited behavior opposite to that of the moisture content. CHP smoked in mesquite wood exhibited the highest TPs absorption rate and the lowest AQ levels. However, the AQ levels in CHP using any wood type exceeded permissible limits (0.02 mg·kg−1) at 12 h of processing, with the control exhibiting the highest AQ concentrations. The highest concentrations of CAPS and DHC were observed at 36 h in all treatments, with lower losses in mesquite wood CHP. The control exhibited the highest TAA values compared to fresh peppers. CHP color (a*, redness) decreased throughout the smoking process. The pecan and mesquite wood treatments resulted in the lowest loss of a* (P < 0.05). These results indicate that using mesquite wood for CHP production promotes higher TPs concentrations with lower AQ levels, followed by pecan wood, when compared to the control. These findings suggest the need to investigate the mechanisms of AQ formation to achieve CHP parameters within the regulatory limits with good quality.

Effects of conductive drying on drying kinetics and retention of bioactive compounds in mistletoe leaves

The aim of this study was to investigate the effect of conductive drying on the quality characteristics of mistletoe leaves. Drying generally took place in both constant and falling rate periods. Page and Modified Page models with the highest R2 and lowest χ2 and RMSE values were found to satisfactorily describe the drying behavior of the mistletoe leaves. Changes in total phenolic content (TPC), total antioxidant activity (TAA), and ascorbic acid content (AAC) of mistletoe leave samples were measured during conductive drying at three different temperatures (50, 60, and 70 °C). Total phenolic content was determined as 686.61±2.96 mg GAE/100 g DM in fresh samples and ranged between 150.97–105.09 mg GAE/100 g DM after drying. The total antioxidant activity values of dried mistletoe leaves decreased significantly compared to fresh ones. The ascorbic acid content of mistletoe leaves was found to be 84.00±2.42 mg/100 g DM before drying. The total antioxidant activity and ascorbic acid content samples were degraded following the second order reaction kinetics. However, the change in the total phenolic content occurred in accordance with the first-order kinetic model. The higher antioxidant activity, phenolic compounds, and ascorbic acid content, and lower half-life values were observed in conditions where the temperature (50 °C) is low.

Compositional profiling and sensory analysis of cauliflower by-products-enriched muffins.

Cauliflower (Brassica oleracea var. botrytis) by-products (leaves, stems, stalks) (CBP) were successfully utilized in muffins as a model system and their feasibility of incorporation was investigated. CBP powder-based muffin formulations were made by the progressive replacement of wheat flour (WF) with 10%, 20%, and 30% of CBP. The physicochemical, pasting properties, antioxidant potential, textural characteristics, and sensorial attributes were analyzed. Substitution of CBP significantly (p < .05) resulted in an upsurge in crude protein, crude fiber, minerals, total phenolics, and total flavonoid contents, as well as total antioxidant activity values of muffins. The pasting properties were influenced by monitoring an increase in peak, breakdown, final, and setback viscosities. Although the addition of an increasing amount of CBP improved the nutritional characteristics, however, the increased level of replacement (>10%) had significant adverse effects on baking and physical characteristics. The specific loaf volume of the developed muffins decreased the crumb color which became darker, and enriched muffins were hardened in texture. Furthermore, sensory evaluation confirmed the positive effects of CBP incorporation only up to 10%. Overall, present results highlighted that supplementation of wheat muffins with 10% CBP is a beneficial approach to enrich them with nutrients and intensify their antioxidant potential.

Physicochemical attributes and bioactive properties of statice leaves

Some ornamental plants have been receiving special attention, not only for their use in landscaping, but also because of their bioactive, aromatic and spicy properties. The objective of this study was to characterize physical and chemical attributes and antioxidant activity in leaves of three cultivars of statice (Limonium sinuatum). The cultivars used were QIS White, QIS Blue Dark, and QIS Yellow. The content of total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA ratio, pH, vitamin C, anthocyanin, flavonoids, total phenolic compounds (TPC), total antioxidant activity (TAA) and the relationship between TPC and flavonoids and TAA were analyzed for each cultivar. The results showed that the leaves of the QIS White cultivar have a higher TSS/TTA ratio, indicating better flavor. The QIS White cultivar also showed higher vitamin C and flavonoid content. The cultivars QIS White and QIS Blue Dark showed higher TPC contents, but there were no differences in TTA and anthocyanin content. The average TAA values were 94.3%, indicating that all cultivars have a high capacity to sequester the DPPH radical. There was a positive relationship between TPC with flavonoids and TAA (R2=0.6168 and 0.8826, respectively). The leaves of statice plants, traditionally used in landscaping and as a cut flower, have potential for use in human food.

Impact of Postharvest Putrescine Treatments on Phenolic Compounds, Antioxidant Capacity, Organic Acid Contents and Some Quality Characteristics of Fresh Fig Fruits during Cold Storage

The storage and shelf life of the fig, which has a sensitive fruit structure, is short, and this results in excessive economic losses. In a study carried out to contribute to the solution of this problem, the effect of postharvest putrescine application at different doses (0, 0.5, 1.0, 2.0, and 4.0 mM) on fruit quality characteristics and biochemical content during cold storage in figs was determined. At the end of the cold storage, the decay rate and weight loss in the fruit were in the ranges of 1.0-1.6% and 1.0-5.0 %, respectively. The decay rate and weight loss were lower in putrescine-applied fruit during cold storage. Putrescine application had a positive effect on the changes in fruit flesh firmness values. The SSC rate of fruit varied between 14 and 20%, while significant differences in the SSC rate occurred depending on storage time and putrescine application dose. With putrescine application, the decrease in the acidity rate of the fig fruit during cold storage was smaller. At the end of the cold storage, the acidity rate was between 1.5-2.5% and 1.0-5.0. Putrescine treatments affected total antioxidant activity values and changes occurred in total antioxidant activity depending on the application dose. In the study, it was observed that the amount of phenolic acid in fig fruit decreased during storage and putrescine doses prevented this decrease. Putrescine treatment affected the changes in the quantity of organic acids during cold storage, and this effect varied depending on the type of organic acid and the length of the cold storage period. As a result, it was revealed that putrescine treatments can be used as an effective method to maintain postharvest fruit quality in figs.

Degradation kinetics of bioactive compounds in dried mistletoe leaves during storage

This work evaluated the effect of air atmosphere packaging and modified atmosphere packaging on the quality and nutritional compounds of dried mistletoe leaves during 4 months of storage at 4 and 25 °C temperatures. Mistletoe leaves packaged with modified atmosphere had improved nutritional qualities overall as compared to mistletoe leaves packaged with atmosphere air. At the end of the storage period, water activity values of all samples increased by 0.72%–3.38%. Before storage, the dried mistletoe leaves' total phenolic content was determined to be 301.73 ± 2.49 mg GAE/100 g dry matter. The total phenolic content of the samples decreased by 62.00%–71.96% after four months of storage. It was determined that the highest loss of total phenolic content was observed at room temperature (25 °C) and in the samples packaged with normal atmospheric air. Total antioxidant activity values in MAP2 samples decreased by 23.82% after four months when kept at low temperatures, but the loss was calculated to be 34.48% in cases where they were kept at room temperature. Ascorbic acid content losses in AP, MAP1, and MAP2 samples kept at room temperature were 21.48%, 15.90%, and 14.72%, respectively. In the samples stored at low temperatures, these loss rates were calculated as 16.62%, 13.05%, and 12.05%, respectively. No single model was satisfactory for describing changes in ascorbic acid content, which could not be determined in the samples stored at both 4 °C and 25 °C. The dried mistletoe leaves modified atmosphere packed and stored at low temperatures provided the highest bioactive compound retention.

ABTS/TAC Methodology: Main Milestones and Recent Applications

ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic) acid) is a widely used compound for determining the total antioxidant capacity (TAC) of plant extracts, food, clinical fluids, etc. This photometric assay is based on the reduction by the presence of antioxidant compounds of a well-known metastable radical (ABTS•+) which can be formed via several different approaches and be used in many different determination methodologies such as automated photometric measures in microplates, clinical robots, valuable titrations, and previous liquid chromatographic separation. Another interesting aspect is that, in some cases, the ABTS/TAC method permits sequential hydrophilic and lipophilic antioxidant activity determinations, obtaining total antioxidant activity values through the summatory data of both types of antioxidants. In this work, we present a review of several aspects of the ABTS/TAC, highlighting the major achievements that have made this method so widely used, e.g., ABTS radical formation in hydrophilic or lipophilic reaction media, measurement strategies, automatization, and adaptation to high-throughput systems, as well as the pros and cons. Moreover, some recent examples of ABTS/TAC method applications in plant, human, and animal samples are discussed.

Antioxidant activity of freeze-dried Siberian sturgeon (Acipenser baerii) ovarian fluid

Ovarian fluid is a mass-production nutritionally valuable byproduct of aquaculture of sturgeons. Total antioxidant activity of freeze-dried pasteurized and non-pasteurized ovarian fluid of Siberian sturgeon (Acipenser baerii) was determined to estimate its potential acceptability as an anti-inflammatory and anti-age agent in nutraceuticals. Total antioxidant activity was determined using the certified coulometric measurement method. The value of total antioxidant activity was about 18.6 ± 1.1% of that of a well-known source of antioxidants – tomato fruits, if calculated by dry weight. There was no statistically significant difference between the values of activity for pasteurized and non-pasteurized ovarian fluid, so it is reasonable to pasteurize the fluid for its preservation.

ODP389 Lipid Peroxidation System Reactivity in Adolescents During Constitutional Obesity Non-drug Therapy

Abstract Background In recent years, there has been a worldwide trend toward preventing and controlling childhood obesity by non-drug therapy. The success of this trend largely depends on better understanding the various metabolic and regulatory systems functions. Lipid peroxidation (LPO) - antioxidant defense (AOD) nonspecific system reactivity should be of special attention. The aim of the study was to reveal the lipid peroxidation and antioxidant defense parameters changes in different sex's adolescents during constitutional obesity non-drug therapy. Materials and methods Adolescents of 12-17 years old with constitutional obesity (CO) (22 boys and 24 girls) before and after constitutional obesity non-drug therapy were examined. The therapy included routine recommendations for food consumption modification, motivational education in the School of Rational Eating, a steady diet, a low-calorie diet, aerobic physical exercises (running track), impulse physiotherapy on the rectus abdominis. Healthy teenager's data (20 boys and 16 girls) were used as a control. We analyzed the content of LPO products - diene conjugates (DC), ketodienes and conjugated trienes (KD and CT), TBA-active products and AOD factors activity: total antioxidant activity (TAA), α-tocopherol, retinol, reduced (GSH) and oxidized (GSSG) glutathione, superoxide dismutase activity (SOD). Spectrophotometric and fluorometric methods were used. Results The boys with CO had decreased values of primary LPO products – DC (by 1.35 times lower, p=0. 001) and AOD factors: TAA (by 1.16 times lower, p=0. 036) and SOD activity (by 1.49 times lower, p&amp;lt;0. 0001), against the increased background values of secondary products - KD and CT (by 1.42 times higher, p=0. 046) in comparison with control results. Boys with CO therapy did not lead to normalization of the studied parameters. The girls with CO had decreased values of TAA values (by 1.4 times lower, p=0. 0001), SOD (by 1.42 times lower, p&amp;lt;0. 0001) and α-tocopherol (by 1.33 times lower, p=0. 012) compared to the control group. After the course of therapy, there was an increase in GSSG levels (by 1.14 times higher, p=0. 029). Conclusions This study showed the presence of negative changes in the pro- and antioxidant status in adolescents with CO, which did not normalize after a course of non-drug therapy. Additional pharmacological correction by prescription of antioxidant drugs becomes relevant in addition to the course of non-drug therapy. Presentation: No date and time listed

Terroir Influence on the Antioxidant Activity of Grape Wines

The article analyzes the global wines production and consumption in the period from 2000 to 2020. The authors studied the total antioxidant activity of 19 samples of red wine from the Old and New World. They found that in the studied red wine samples, the total antioxidant activity value was in the range from 8,408 to 19,249 mmol-eq/dm3 . In red Old-World wines samples, the total antioxidant activity values were in the range from 10.056 to 19.249 mmol-eq/dm3 , while the highest were in red wines produced in Italy from the grape varieties Nero di Troia, Corvina and Rondinella, as well as in French wines from the varieties Merlot and Cabernet Franc; the smallest antioxidant activity values were in Italian wines produced from varieties Cabernet Sauvignon and Spanish wines from the varieties Tinta Roriz, Turiga Nacional, Turiga Franca. In the studied samples of red New-World wines, the total antioxidant activity values accounted for the range from 8.408 to 16.456 mmol-eq/dm3 , while the highest values were for Australian wines produced from the Shiraz grape variety and American wines from the Merlot variety; the lowest indexes were for American wine produced from the grape variety Pinot Noir. In the red Russian wines samples, the total antioxidant activity values were in the range from 5.903 to 15.566 mmol-eq/dm3 , while the highest indicators were in the wine from the varieties Merlot and Cabernet Sauvignon produced by the manufacturer “Usadba Divnomorskoe”; the lowest figures were for the wine produced from the “Pinot Noir” variety of the same producer. The antioxidant activity of wines varied from 26.3 to 60.1 % of the recommended daily intake in terms of ascorbic acid (ascorbic acid AOA – (32.024 ± 0.350) mmol-eq/dm3 ). The researchers revealed that the antioxidant activity as an identification marker for French wines must be at least (15.0 ± 0.5) mg-eq/dm3 , for Italian wines – at least 16.5 mg-eq/dm3 , for wines from Cabernet Sauvignon grapes, possible deviation was 5 mg-eq/dm3 . For New-World wines and Russian wines, the antioxidant activity must be at least (10.0 ± 0.5) mg-eq/dm3 , for wines from Pinot Noir grapes, possible deviation was 2 mg-eq/dm3 .

Anthocyanin profile and main antioxidants in pigmented wheat grains and related millstream fractions

AbstractBackground and ObjectivesIncreasing evidence has shown the potential for foods made from anthocyanin‐rich cereal grains to reduce the development and progression of many degenerative chronic diseases. Among cereals, only pigmented rice and maize have been used for food production, whereas for blue and purple wheat grains the food industry has been more limited. In light of this, the present study was aimed at characterizing the whole meal, bran, and flour of the blue bread wheat “Sebesta Blue‐2” and the purple durum wheats “T‐1303” and “‘ELS 6304‐56” in relation to their total phenolic content (TPC), total proanthocyanidin content (TPrC), total anthocyanin content (TAC), and total antioxidant activity (TAA) determined spectrophotometrically, and their anthocyanin profile and TAC determined by high‐performance liquid chromatography (HPLC) (TACHPLC).FindingsAmong the milling fractions, the bran showed the highest phytochemical content and antioxidant activity, with values 1.6–8.3‐ and 4.0–9.3‐fold higher than those observed in the whole meal and flour, respectively. Among genotypes, the highest phytochemical content and antioxidant activity were observed in Sebesta Blue‐2, followed by T‐1303 and ELS 6304‐56. The strongest differences among genotypes concerned the TACHPLC, with values that in Sebesta Blue‐2 were 4.8‐ and 14.1‐fold higher than T‐1303 and ELS 6304‐56, respectively. Multivariate analysis highlighted the best profile in terms of phytochemical content and antioxidant activity in the bran of Sebesta Blue‐2 with very high values of TPC, TPrC, glycosylated anthocyanins, and TAA, followed by the bran of T‐1303, with high‐to‐very high values of TPC, TPrC, anthocyanins and TAA, and the whole meal of Sebesta Blue‐2, with high values of glycosylated anthocyanins and intermediate values of TPC, TPrC, and TAA.ConclusionsThe bran of Sebesta Blue‐2 and T‐1303 could be used as an additive in cereal‐based fortified‐functional foods or could be further processed to produce nutraceutical supplements. The whole meal of Sebesta Blue‐2 could be used as starting material for the preparation of baked products rich in health‐promoting compounds.Significance and noveltyThe present study is one of the few studies to report the anthocyanin profile for the milling fractions of pigmented grains and is the first to report the existence of proanthocyanidins in blue and purple wheat grains and their milling fractions.

Ranunculus gracilis Clarke Rizomunun In Vitro Biyolojik Aktiviteleri

R. gracilis rhizomes were picked from Yenice Forests Karabük province in Turkey. Ethanol was chosen for extraction solvent. Disc diffusion method including filamentous and non-filamentous Gram-positive bacteria, Gram-negative bacteria, and yeast strains was used to evaluate the antimicrobial activity of the extract. DPPH free radical scavenging activity and ferric reducing antioxidant power analysis were performed to determine antioxidant activity. The Folin-Ciocalteu method for determining the total phenolic amount and the AlCl3 method for the total flavonoid content of the extract was chosen. Mean diameters of inhibition zones (IZD) of the bacteria were found in the range of 8.2 mm to 24.45 mm. This value was measured as 17.82 mm and 18.69 mm for yeasts. The total antioxidant activity value of the extract was calculated as 7.08 mg AAE/g extract. The IC50 value was found as 9.097 mg/mL for DPPH free radical scavenging activity. The FRAP value indicated that the reducing power of 1 gram of sample was equivalent to 4.66 μmol of Trolox. The total phenolic content of ethanol extract of R. gracilis rhizomes was determined as 0.414 mg GAE/g, while the flavonoid content was calculated as 0.68 mgQE/g. The analyzed ethanolic extract of R. gracilis rhizomes demonstrated that the biological activity level could be considered significant according to the obtained results.

Изменения в системе липопероксидации при базовой терапии экзогенно- конституционального ожирения у подростков разного пола

Objective. To reveal changes in lipid peroxidation parameters and antioxidant protection components against the background of standard non-pharmacological therapy for exogenous constitutional obesity in adolescents of different sex. Patients and methods. Forty-six adolescents aged 12–17 years with obesity were examined before and after non-pharmacological therapy. The control group included 36 healthy adolescents. We analyzed the composition of lipid peroxidation products – conjugated dienes (CD), ketodienes and conjugated trienes (KD and CT), TBA-active products and activity of antioxidant protection factors: total antioxidant activity (AOA), levels of α-tocopherol, retinol, reduced and oxidized glutathione (GSH, GSSG), their ratio (GSH/GSSG ratio), superoxide dismutase (SOD) activity. Spectrophotometric and fluorometric methods were used. Results. Male adolescents with obesity had lower values of primary lipid peroxidation products compared to the control group – CD (1.35-fold, p = 0,001) and antioxidant protection factors: total AOA (1.16-fold, p = 0,036) and SOD activity (1.49-fold, p &lt; 0.0001), whereas secondary products – KD and CT were elevated (1.42-fold, p = 0,046). Standard therapy in male adolescents did not lead to normalization of the studied parameters. Significantly lower were the values of total AOA (1.4-fold, p = 0.0001), SOD activity (1.42-fold, p &lt; 0.0001) and α-tocopherol (1.33-fold, p = 0.012) in female adolescents with exogenous constitutional obesity compared to the control group. After standard therapy, there was an increase in GSSG levels (1.14-fold, p = 0.029). Conclusion. The presence of negative changes in the pro- and antioxidant status in adolescents with obesity, which was not normalized after a course of standard therapy, was shown. Additional pharmacological correction by prescription of antioxidant drugs becomes relevant. Key words: antioxidant protection, standard therapy, oxidative stress, adolescents, exogenous constitutional obesity

Synthesis and Characterization of Antioxidant Biphenyl Appended 1,2,3‐Triazoles as Potential Chemo‐Sensor for Sn2+ Ions: Excellent Selectivity and Low Detection Limit

AbstractDesigning of chemo‐sensors is a new scope of intrigue among researchers. After inspecting the beneficial and harmful effects of Sn(II) metal ions in living species, 1,2,3‐ Triazole based chemo‐sensor 4 a have been synthesized via click route. In the current article, literarily new 1,2,3‐Triazoles (4 a–4 d) have been synthesized and identified via various spectroscopic means such as NMR(1H &amp; 13C), IR and mass spectrometry. Triazole 4 a was explored for recognition properties via absorption and emission spectroscopy and found specific and selective for Sn(II) metal ions. The recognition of Sn2+ metal ions by probe 4a was not interfered because of other tested metal cations. The probe has very low detection limit of 0.47×10−7 M and 3.8×10−9 M via ultraviolet and fluorescence spectroscopy respectively which is lower than many previously reported sensors. The B−H plot and stern volmer's plot confirmed a high binding affinity between probe 4a and tin (II) metal ion. The association constant (Ka) and stern volmer constant (Ksv) were calculated as 13.36×105 M−1 and 12.6×106 M−1 from B−H plot and stern volmer's plot respectively. The Stoichiometric ratio between chemo‐sensor 4 a and Sn2+ metal ions was confirmed as 1 : 1 by the job's plot. Moreover, in this study, the synthesized compounds 4(a–d) were examined for their antioxidant properties. The total antioxidant activity (TAA) results indicate that the synthesized triazoles 4(a–d) found to be excellent postulant for radical scavenging. TAA values for 4 a, 4 b, 4 c and 4 d are found to be 4.65±0.2, 6.79±0.3, 6.29±0.2, 5.06±0.1 (mM)(eq. ascorbic acid) per 100 mM of particle respectively.

Degradation kinetics of color, antioxidant activity, total phenolic content, and physicochemical investigation of blanched amaranthus leaves puree by FTIR

The aim of the analysis was to find the optimal blanching period for Amaranthus tricolor leaves purees (ATP), that would result in the highest retention of total antioxidant activity (TAA), total polyphenol content (TPC), and chlorophyll (Chl) to boost their functional activity. ATP was blanched for 1, 3, 5, and 7 minutes at 70, 80, and 900C for this analysis. The influence of blanching times on physicochemical, TAA, TPC, and Chl values was then studied. The unblanched and blanched puree was investigated using FTIR analysis (900C for 3 min). The variations in moisture content in ATP were not significant in the physicochemical analysis. There is a substantial decrease in ash content and a rise in pH value with increasing blanching time (p&lt;0.05). As the blanching time for ATP was raised, the percent of the water-soluble index improved significantly (p&lt;0.05). Content of TAA, TPC, and Chl in the ATP was steadily reduced as the blanching time was increased. The degradations of TAA, TPC, and Chl of ATP are well fit by first-order kinetic models, with coefficient determination (R2) ranging from 0.86-0.98. The presence of ketone and alcohol is confirmed by the functional group obtained during the FTIR analysis of the sample. The results can promote household blanching as well as the food industry to prescribe a certain blanching period for vegetables to preserve their TAA, TPC, and Chl values.

Effect of agar and gellan gum on structured guava (Psidium guajava L.): Rheological behavior and gastrointestinal digestion in vitro

Structured guava (SG) was produced by inducing gelation of guava pulp adding agar and gellan gum (GG). The rheological properties, as well as in vitro bioaccessibility of ascorbic acid (AA), total antioxidant activity (TAA) and total extractable polyphenols (TEP) were investigated. The results illustrated that the SG gel network made from agar and low acyl gellan (LAG) was completely developed at temperatures close to 20 °C. LA75/HA25 showed higher elastic behavior in time sweep. The AA analysis of the pulp and SG revealed that these compounds remained practically unchanged after gastrointestinal digestion in vitro (GID), with a higher bioaccessibility percentage. The average values of TAA and TEP of the structured products were close to those of the guava pulp, with no interference from the use of agar and GG. The Optimized Descriptive Profile showed that the hydrocolloid used influenced the sensory attributes of the SG, changing the texture and appearance.

Cluster characteristic of water used by energy facilities by total antiocidant activity

Energy facilities are located on most large reservoirs, therefore, the issue of water quality is especially acute in the water area of such water bodies. The article describes 9 clusters of water with values of total antioxidant activity, isolated now on the basis of numerous analyses. Water with a simplified structure is distinguished, containing 1 cluster and characterized water bodies with an abundance of life. Ordinary water with 2 clusters in the structure is water widely used by humans for household consumption. Water with 3-4 clusters observed in artesian wells. The most complex in cluster composition is spring water (5 clusters). The complex cluster structure of water made it possible to propose an index of water structure, which reflects the percentage of clusters with certain values of total antioxidant activity and the degree of water trophy. As a result, the work provides the recommendations on the values of total antioxidant activity of water at the water intake and offtake of combined Heat and Power plant.

Assessment of the nutritional value and prospects of using ziziphus fruit for a healthy human diet

In modern conditions of development of society, food products with antioxidant and immunostimulating properties are becoming increasingly important. This led to research to identify the natural sources of such compounds. Ziziphus fruits grown in the subtropical conditions of the Krasnodar territory of the Apsheron, Chinese 2A, Koktebel and Lakomy varieties were selected as objects of research. It was found that the highest content of pectin substances is allocated to the late-maturing variety Lakomy (7.23%), the lowest–mid-maturing variety Apsheron (4.72%). The fractional composition of pectin substances is represented by protopectin (PP) and soluble pectin (SP). At the same time, the highest content of both SP and PP was found in the ziziphus Lakomy variety (1.73 and 5.50%, respectively). By the highest content of flavonoids and the amount of phenolic compounds, the ziziphus Koktebel variety is distinguished, the lowest - the Chinese 2A variety. All varieties of unabi fruits had high values of total antioxidant activity. At the same time, the lowest antioxidant activity was observed in the Chinese 2A variety (381.9 mg/100 g), and the highest–in the Nikitsky Botanical garden selection variety Koktebel (503.2 mg/100 g). The antioxidant activity in the Apsheron variety (493.4 mg / 100 g) was 1.3 times higher than that in the Chinese variety 2A and slightly different from the Lakomy variety (488.3 mg/100 g). Experimental data confirmed the nutritional value of ziziphus fruits, which allows us to recommend them as a functional source of antioxidants and pectin substances.