Phenoxyl Radicals Research Articles

Influence of time-temperature in the antioxidant activity, anthocyanin and polyphenols profile, and color of Ardisia compressa K. extracts, with the addition of sucrose or citric acid

The objective of this study was to analyze and optimize the influence of heating time and citric acid (CA) or sucrose addition of Ardisia compressa K. extracts on phenolic compounds (TPC), monomeric anthocyanins (MAA), antioxidant activity (TAC), color density (CD), and hue tint (HT), using a full factorial design. Extractions were performed: temperature (25, 50, or 70 °C), time (15, 30, 60, or 90 min), CA (0.0 or 0.02 g), and sucrose (0.0 or 5.0 g). HPLC-DAD-ESI-MS was conducted in extracts without additives and with the addition of CA (0.02 g) or sucrose (5.0 g), at 25, 50, or 70 °C for 15 min. CA-added extracts showed maximum TPC, MAA, TAC (DDPH and ABTS assays), and CD values, with the lowest HT values. Malvidin 3-O-galactoside and myricetin-O-hexoside were the predominant anthocyanin and non-anthocyanin polyphenols. Time, temperature, and solute influenced the optimized extraction of TPC, MAA, anthocyanins, TAC, CD, and HT.

Potential Effects of the Different Matrices to Enhance the Polyphenolic Content and Antioxidant Activity in Gluten-Free Bread.

Gluten-related disorders, including celiac disease, wheat allergy, and non-celiac gluten sensitivity, have emerged as a significant phenomenon affecting people worldwide, with an estimated prevalence of nearly 5% globally. The only currently available treatment for this disease involves the exclusion of gluten from the diet, which is particularly challenging in the case of bakery products. Gluten-free bread (GFB) presents certain disadvantages when compared to traditional wheat bread, including inferior sensory attributes, technological characteristics, and lower protein and fiber content. Numerous studies have focused on strategies to improve these aspects of GFB. However, there are limited reviews regarding the content of the bioactive compounds of GFB, such as polyphenols. Polyphenols are molecules found in various foods that play a vital role in protecting the body against oxidative stress. This is particularly relevant for individuals with gluten intolerance or celiac disease, as they often experience increased oxidative stress and inflammation. Therefore, the objective of this review is to explore the use of different strategies for increasing the polyphenolic content and the antioxidant properties of GFB. Gluten-free cereals and pseudocereals are the most used matrices in GFB. Buckwheat can be a valuable matrix to enhance the nutritional profile and antioxidant properties of GFB, even more so when the whole grain is used. In the same way, the addition of various by-products can effectively increase the bioactive compounds and antioxidant activity of GFB. Furthermore, regarding the contribution of the phenolics to the bitterness, astringency, color, flavor, and odor of food, it is essential to analyze the sensory properties of these breads to ensure not only enriched in bioactive compounds, but also good consumer acceptance. In vitro studies are still in few number and are very important to execute to provide a better understanding of the bioactive compounds after their consumption.

Effect of extraction solvents on polyphenol content and antioxidant activity of carob tree (Ceratonia siliqua L.) leaves

Carob tree (Ceratonia siliqua L.) is widely used in traditional medicine and food. The aim of this study was to determine the most appropriate extraction solvent to optimize the extraction of polyphenols and flavonoids from the leaves, in order to obtain the highest antioxidant activity. In this context, the effects of six different solvents (100% methanol, 100% ethanol, 100% acetone, 50% (v/v) aqueous methanol, 50% (v/v) aqueous ethanol and 50% (v/v) aqueous acetone) with different polarities on the polyphenol content and antioxidant activity of carob tree leaf extracts were investigated. The total polyphenol and total flavonoid contents, as well as the antioxidant activity determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method of the extracts were evaluated. The results showed that carob tree leaves extracted with 100% methanol presented the highest values in terms of total polyphenol content (11.33± 0.08 mg EAG/g DM), total flavonoid content (8.55± 0.34 mg EC/g DM) and DPPH inhibition percentage (79.29 ± 3.75%). High positive correlations between total polyphenols, total flavonoids and antioxidant activity of carob tree leaf extracts were also observed. These results indicate that carob tree leaf extract obtained using an appropriate extraction solvent was able to enhance the protective effect against oxidative damage associated with free radicals.

Choline chloride-urea-based natural deep eutectic solvent for highly efficient extraction of polyphenolic antioxidants from Pluchea indica (L.) Less leaves

Pluchea indica leaves (PIL) is a polyphenolic-rich plant. Polyphenols, such as phenolics and flavonoids, are natural antioxidants. This study aims to evaluate the ability of natural deep eutectic solvent (NADES) based on ultrasonic-assisted extraction (UAE) for highly efficient extraction of the polyphenolic antioxidant compounds from PIL. Choline chloride-urea (ChCl-U) was selected based on screening of 17 types of NADES. This study uses Response Surface Methodology (RSM) to help determine optimal extraction conditions. The selected variables include molar ratio, temperature, and the water addition in the NADES. The responses used for the RSM study were total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and reducing power (RP) methods with microtiter analysis. The best condition for polyphenolic antioxidants extraction using ChCl-U NADES was a 1:3 molar ratio, temperature of 52 °C, and 26% of water addition in NADES. Under these conditions, the extraction of total phenolics and flavonoids from PIL with antioxidant activity increased up to 1.2 folds and 3.1 folds compared with 50%-ethanol and methanol, respectively. The morphology of the leaves before and after extraction was also evaluated with a scanning electron microscope (SEM) to observe the effects of ultrasonic vibrations with different solvents. Furthermore, the compound di-caffeoylquinic acid (DCQA) in PIL was selectively found in ChCl-U extract through quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS/MS) analysis. Thus, ChCl-U combined with UAE can be developed for polyphenolic extraction from PIL for extract production as an antioxidant.

A Multipurpose Sustainable Farming System for Tobacco Crops in the Mediterranean Area

The present study aimed to test a multipurpose sustainable tobacco farming system allowing more efficient use of production factors (e.g., mineral N fertilizer) thanks to larger commercial yields, albeit diversified (smoke products, bioactive compounds for nutraceutical and cosmeceutical uses, energy), per unit of land area. Three tobacco types (dark air-cured, IBG; light air-cured, Bu; dark fire-cured, Ky) were grown in the field in 2021 on three different soils (sandy clay loam, SCL; sandy loam, SL; clay loam, CL). The total waste biomass (WB, kg dry weight, d.w. ha−1) was measured. Commercial leaves yield (CLY, kg d.w. ha−1), N agronomic efficiency (NAE, kg d.w. kg−1 N), total polyphenols content (TP, mg kg−1 d.w.), antioxidant activity (ABTS, DPPH and FRAP, mmol Trolox Equivalent, TE, kg−1 d.w.) and yield of polyphenols (PY, kg ha−1) were determined. The calorific value (CV, MJ kg−1 d.w.), volatile matter (VM, %) and ash contents (%) were also measured, and biomass energy yield (BEY, GJ ha−1 yr−1) was then calculated. Very high percentages (>40%) of total biomass produced by the different tobacco types were pre-harvest waste. NAE increased by 2- to more than 8-fold thanks to a greater potential commercial biomass produced with the same amount of N fertilizer used. Four main components were found in the tobacco polyphenols profile, namely 3-O-CQA, luteolin 7 rutinoside, rutin and quinic acid, which accounted for more than 80% of TP. BEY ranged between 122.3 GJ ha−1 yr−1 (Bu) and 29.9 GJ ha−1 yr−1 (Ky). Both polyphenols yield and energy potential per unit land area and/or per growing season appeared competitive with those from other herbaceous crops. The proposed multipurpose system appeared as a production circuit characterized by a virtuous and sustainable flow of resources.

A Clean-Label Formulation of Fortified Yogurt Based on Rhododendron Flower Powder as a Functional Ingredient.

The world-wide-dispersed Rhododendron is a tiny, evergreen plant with vivid red or pale pink blossoms that is a member of the Ericaceae family and is well-known for its stunning flowers. To improve yogurt's nutritional profile and sensory qualities, this study investigates an innovative application of Rhododendron flower powder (RFP). The potential health benefits of Rhododendron flowers, which are a rich source of bioactive compounds such as polyphenols and antioxidants, have attracted attention. Consequently, the physicochemical, phytochemical, and sensory qualities of fortifying yogurt with RFP at various concentrations were studied. The results showed that the texture and color of the yogurt were highly influenced by the addition of RFP. The addition of this functional ingredient also resulted in a significant increase in the yogurt's polyphenol content and antioxidant capacity. These findings demonstrate the suitability of RFP in yogurt formulations as a functional food ingredient, being a good source of phenolics.

Purification of the apple pomace polyphenol extract using adsorbent resin

AbstractPolyphenols from agro-industrial waste particularly of fruit origin are a reliable source of antioxidants and antimicrobials that can be used as natural food additives. Organic solvents play an important role in extracting the polyphenols, however, inefficiency in exerting bioactivity and interference with the organoleptic properties are among the reasons that hinder their use as food additives. These problems can be alleviated by purification. In this study, the effect of resin types and elution solvent for purification of the apple pomace extracts on total phenolic content (TPC) and antioxidants were investigated. Crude ethanolic extracts were purified using amberlite resins (XAD7HP and FPX66) in a glass column (25 × 310 mm). The sorption flow rate was 2 Bed volume (BV) per hour, rinse 2 BV per hour, and desorption was 2 BV per hour. Final wash and regeneration were each done by 2 BV per hour. Polyphenol content and antioxidant capacity were quantified spectrophotometrically using Folin-Ciocalteu and Ferric reducing ability of plasma (FRAP) assays respectively. Polyphenol recovery was 50% in XAD7HP (Lowest) using ethanol and 69% in FPX66 (Highest) using acetone. For the case of FRAP recovery, 76% (Lowest) was observed in FPX66 using ethanol while 93% (Highest) was observed in XAD7HP using acetone. Conclusively, FPX66 is the ideal resin for the purification of apple pomace extracts for enhancing antioxidant activity compared to XAD7HP. Further, acetone seems to be a good desorption solvent compared to ethanol.

Gestational Fisetin Exerts Neuroprotection by Regulating Mitochondria-Directed Canonical Wnt Signaling, BBB Integrity, and Apoptosis in Prenatal VPA-Induced Rodent Model of Autism.

Embryonic valproic acid (VPA) has been considered a potential risk factor for autism. Majority of studies indicated that targeting autism-associated alterations in VPA-induced autistic model could be promising in defining and designing therapeutics for autism. Numerous investigations in this field investigated the role of canonical Wnt signaling cascade in regulating the pathophysiology of autism. The impaired blood-brain barrier (BBB) permeability and mitochondrial dysfunction are some key implied features of the autistic brain. So, the current study was conducted to target canonical Wnt signaling pathway with a natural polyphenolic modulator cum antioxidant namely fisetin. A single dose of intraperitoneal VPA sodium salt (400 mg/kg) at gestational day 12.5 induced developmental delays, social behaviour impairments (tube dominance test), and anxiety-like behaviour (sucrose preference test) similar to autism. VPA induced mitochondrial damage and over-activated the canonical Wnt signaling which further increased the blood-brain barrier (BBB) disruption, apoptosis, and neuronal damage. Our findings revealed that oral administration of 10 mg/kg gestational fisetin (GD 13-till parturition) improved social and anxiety-like behaviour by modulating the ROS-regulated mitochondrial-canonical Wnt signaling. Moreover, fisetin controls BBB permeability, apoptosis, and neuronal damage in autism model proving its neuroprotective efficacy. Collectively, our findings revealed that fisetin-evoked modulation of the Wnt signaling cascade successfully relieved the associated symptoms of autism along with developmental delays in the model and indicates its potential as a bioceutical against autism.

Comparative evaluation of biometrical and biochemical characteristics of three Rumex representatives: <i>Rumex acetosa</i> L., <i>Rumex sanguineus</i> L. and <i>Rumex confertus</i> Willd.

Increase in green vegetables popularity in nutrition and medicine promotes investigations of new cultivar and hybrid biochemical parameters. Nutritional value and antioxidant status of three Rumex representatives: Rumex acetosa L. (Krupnolistny cv.), Rumex sanguineus L. (prospect genotype) and Rumex confertus Willd. were studied. Antioxidant defense parameters (total antioxidant activity, polyphenol and ascorbic acid content) decreased in accordance to: Rumex sanguineus L. > Rumes confertus Willd. > Rumex acetosa L. Thus the ascorbic acid content in bloody dock (R. sanguineus) reached 129 mg/100 g which was 1.48 times higher than in Russian dock (R. confertus) and 3.17 times higher than in garden sorrel (R. acetosa). The total chlorophyll content was also the highest in bloody dock (17.74 mg/g d.w.) compared to 15.88 mg/g in R. confertus and 13.07 mg/g in R. acetosa leaves. The new R. sanguineus genotype was characterized by high decorative properties and demonstrated twice higher oxalic acid content compared to R. acetosa, Krupnolistny cv., and 1.5 times higher value than in R. confertus. High decorative and medicinal value of R. sanguineus was connected to a great extent with the intensive anthocyanin accumulation reaching 7.2% and high nitrate content. The results of the present study indicate high prospects of R. sanguineus genotype utilization in landscape design, food industry and medicine.

Seed Soaking Using Methanol Kalanchoe pinnata Leaf Extracts Induces Rice Resistance against Bacterial Leaf Blight

Bacterial leaf blight (Xanthomonas oryzae pv. oryzae) is a significant rice disease. Aqueous crude extracts of Kalanchoe pinnata were shown to induce rice resistance against the disease. This study aims at testing the disease-reducing effects of K. pinnata leaf extracts using the liquid–liquid extraction method with three different solvents (dichloromethane, methanol, and water). This serves as a basis to select appropriate extracts for effective disease control. Three concentrations (1, 1.5, and 2%) of each extract were tested using seed soaking. The extracts did not show adverse effects on seed germination and seedling growth. Methanol extracts showed significantly different effects compared to those of the untreated control. The involvement of induced resistance in the disease reduction was shown through activities of the four defense-related and antioxidant enzymes, i.e., peroxidase (POX), catalase (CAT), polyphenol oxidase (PPO), and phenylalanine ammonia lyase (PAL). Using 1% methanol extract, activities of POX and CAT involved in hydrogen peroxide production in rice tissues increased 1–4 days after pathogen inoculation (DAI) and remained at high levels until 6 DAI. Activities of PPO and PAL involved in resistance signaling pathways significantly increased after pathogen inoculation. Activities of the four enzymes generally increased after pathogen inoculation and reached higher levels with extract applications.

Influence of the Aging of Apple Wines with Oak Chips on the Quality and Sensory Parameters of the Wines

Abstract This study investigated the effect of the oak chips added at different dosages and stages of apple wine production on its oenological, antioxidant and sensory properties. In the study, medium-toasted or heavily-toasted oak chips (at a concentration of 3 or 6 g/L) and ethanol extracts prepared from them (at a dose of 1 or 2 mL/100 mL) were used. Basic oenological parameters (OIV), total polyphenol content (Folin-Ciocalteu method), antioxidant activity (ABTS assay), color (CIELAB) and organoleptic assessment of the wine were evaluated. Although the use of chips had no significant effect on the ethanol content and wine extract, it caused a significant change in volatile acidity. Furthermore, the antioxidant activity of the wines correlated closely with the concentration of polyphenolic compounds and these parameters were significantly higher after contact with medium-toasted chips. The apple wines had high values of lightness and yellow color, and the addition of chips did not significantly affect the color parameters (CIELAB). In the sensory assessment, the control wine (without chips) received the lowest scores, while significantly higher scores were given to the wine with the addition of 6 g/L of heavily-toasted chips, which was characterized by intense smoky, toasty, woody and vanilla notes.

Antioxidant potential and chemical composition of new generation extruded snack pellets supplemented with fresh broccoli addition

Abstract The therapeutic potential of broccoli has been highlighted by its function in the prevention of cancer, diabetes and other diseases. As a result, there is a great deal of interest in creating innovative functional foods supplemented with broccoli. In the extrusion-cooking process, raw materials based on potato mixes with the addition of fresh broccoli (Brassica oleracea L. var italica, Brassicaceae) were used to create new generation extruded snack pellets. A prototype single screw extruder-cooker with L/D=20 was utilized, and various processing conditions (screw speed 60 and 100 rpm, as well as either 32 and 36% levels of initial moisture content) were applied. Mixtures of 10% and 30% fresh broccoli contents were investigated. The final snack pellets obtained under such processing conditions were determined for their antioxidant potential, polyphenols, proximate composition and fatty acids profile. We found that in the presence of fresh broccoli in blends, higher screw speed and higher moisture content allowed obtaining (in most samples) a higher polyphenal content in the resulting pellets. Over all, the antioxidant potential of snack pellets increased with the addition of fresh broccoli. Pellets with 30% addition of the broccoli processed at screw speed 100 rpm at moisture content of 32% displayed the highest total polyphenols content and highest antioxidant activity. Moreover, such samples demonstrated notable increase in the content of total protein, crude ash, as well as MUFA and PUFA in the total amount of fatty acids.

Conventional vs. Organic: Evaluation of Nutritional, Functional and Sensory Quality of Citrus limon.

Organic farming is growing rapidly worldwide since it is perceived as more respectful of the environment than conventional farming. In this sense, organic agriculture is highly appreciated by consumers since consumers around the world believe that organic food has a higher content of beneficial compounds for health and consider it of higher quality. For that reason, the objective of this research was to evaluate the nutritional, sensorial, and functional quality of the 'Fino 49' lemon grafted on Citrus macrophylla in conventional and organic cultivation. Fatty acids, amino acids, total phenol, and polyphenols were quantified, antioxidant activity was measured, and sensory descriptive analysis was performed. Conventional farming led to an increase in amino acid content (641 mg L-1) and an increase in polyunsaturated fatty acids (254 mg 100 g-1) and monounsaturated fatty acids (37.61 mg 100 g-1). On the other hand, organically produced lemon fruits had better sensory profile (highlighting overall aroma (6.5), lemon odor (6.8), sourness (5.8), floral (0.6), and fresh lemon flavor (9.8)), and lower thrombogenicity index (0.15). The type of cultivation (organic and conventional) had no influence on the antioxidant activity (~1.60, ~3.08, and ~4.16 mmol Trolox L-1 for ABTS+, DPPH•, and FRAP, respectively) and polyphenols content (85.51 and 86.69 conventional and organic, respectively). However, to establish the advantages and disadvantages of different types of cultivation on lemon quality more studies are needed.

Mechanism-Based Targeting of Sickle Cell Pathobiology and Pain with Novel Transdermal Curcumin

Pain is a debilitating consequence of sickle cell disease (SCD). We examined the potential of novel topical transdermal curcumin (TDC) gel with transdermal systemic delivery to target pain and SCD pathobiology. Curcumin is an antioxidant and anti-inflammatory polyphenol with therapeutic potential but has poor oral bioavailability. TDC gel (Vasceptor TM, Vascarta Inc.), containing 0.1 M of curcuminoids (derived from Curcugen, Dolcas-Biotech, LLC), or vehicle were applied (0.1 mL) topically by gentle rubbing to the abdomen on alternating days for 3 weeks followed by analysis of blood, organ pathology and skin secretome. Using high-performance liquid chromatography, we found that curcumin levels peaked in the plasma (7.87 µg/mL) and blood cells (6.78 µg/mL) 60 min following administration in C57BL/6 mice, thus, showing efficient bioavailability. Next, we used humanized ‘ sickle‘, homozygous transgenic mice ( HbSS-BERK) expressing >99% human sickle hemoglobin (HbSS) without mouse α- and β-globins. These mice mimic the pathobiology and features of pain observed in persons with SCD. We observed that TDC application in male and female HbSS led to a significant decrease in hyperalgesia over the 21 days (D) of treatment. Mechanical hyperalgesia significantly decreased after 14D of treatment in males and after 21D in females (p<.05 and p<.01, respectively Vs. BL). Similarly, cold hyperalgesia (paw withdrawal frequency on cold plate at 4˚C) decreased significantly in males after 24 hours and in females after 7D of TDC treatment (p<.05 and .01, respectively Vs. BL). Non-evoked cold avoidance showed that males spent significantly more time in the colder chamber at 23ºC on 14D, and females did so on 21D after TDC treatment (p<.001 & p<.01, respectively Vs. BL). Throughout 21D TDC treatment, females showed significantly lower analgesic response in cold hyperalgesia compared to male HbSS, similar to relatively poor response to analgesia in female Vs. male individuals with SCD. The amelioration of hyperalgesia for 21D with TDC suggests a disease-modifying effect. Indeed, we observed a significant increase in hematocrit (p<.05), a reduction in reticulocytes (p<.05), and an appreciable increase (43.2%) in Hb and decreased lactate dehydrogenase activity in the blood of TDC-treated HbSS mice Vs. vehicle (p<.01). RBCs from TDC treated HbSS mice showed enhanced ATP levels (p <.01) and reduced protein carbonylation, both biomarkers of protein oxidation (p<.045) Vs RBCs from vehicle-treated HbSS. Histopathology showed a significant reduction in vascular congestion and iron deposits in TDC-treated male HbSS compared to vehicle in the spleen (p<.0003 & p<.001, respectively) and in % fields involved in hepatic infarcts and iron deposits (p<.02 & p<.044, respectively). Together, decreased hemolysis, increased Hb, hematocrit, and ATP suggest RBC stabilization, improved mitochondrial metabolism, and reduced oxidative stress and organ damage, leading to a disease-modifying effect of TDC. TDC also significantly reduced global inflammatory marker serum amyloid-P (p<.05) and inflammatory cytokines in the skin secretome with a concomitant reduction in interleukins [2 (p<.05), 4 (p<.01), and 6 (p<.01)], monocyte chemoattractant protein 1 (MCP-1; p<.01), interferon-gamma (IFN-γ; p<.05), granulocyte macrophage-colony stimulating factor (GM-CSF; p<.01), and regulated on activation, normal T-cell expressed and secreted protein (RANTES; p<.05) compared to vehicle. MCP-1 contributes to neuropathic pain and inflammation; GM-CSF stimulates granulocyte differentiation and growth. Both RANTES and MCP-1 may also activate mast cells. TDC led to a significant decrease in cutaneous mast cell degranulation (p<.001) Vs. vehicle in sickle mice. These data strongly suggest an anti-inflammatory effect of TDCby targeting the release of cytokines and inhibiting granulocyte activity. TDC significantly ameliorates hyperalgesia (chronic pain), inflammation, hemolysis, oxidative stress, and organ damage and improves mitochondrial function and hematological parameters of SCD pathobiology, indicative of disease modifying and anti-nociceptive effects. The results suggest if started early in life, the use of an easy-to-deploy novel TDC formulation, with increased bioavailability and non-toxic properties that directly target sickle cell pathobiology, may prevent chronic pain in SCD.

Effect of plant extracts on some quality parameters of canned mixed sweet corn-red bean

The leading export product of Hungary is canned sweetcorn, which is available in single-component or blended varieties with a focus on colour retention, for wich the food industry mainly uses ascorbic acid and EDTA in the brine of canned vegetable. Thoughtful customer behavior is pushing the food industry to switch to natural plant extracts instead of synthetic additives. In order to investigate if acerola plant extract is suitable as a replacement for ascorbic acid, we investigated the potential uses of two varieties of acerola extract in three different concentrations in the case of canned mixed sweet corn and red bean. After production, and after 1 week of thermostating at 55°C and storage at room temperature for 4 and 8 weeks, the changes in pH value, salt concentration, water-soluble dry matter content, colour, total polyphenol content, and antioxidant capacity of the brine were all evaluated in this experiment. The results showed that both acerola extracts were promising in fixing the colour, with the higher application of the first extract and the lowest and highest dosage of the second extract showing the best results. During storage, the polyphenol content and antioxidant capacity of some samples decreased slightly compared to their initial values.

Polyphenol Composition, Antioxidant Capacity and Xanthine Oxidase Inhibition Mechanism of Furong Plum Fruits at Different Maturity Stages.

An experiment was conducted on the polyphenol content, flavonoid content, anthocyanin content, and antioxidant capacity of Furong plum (Prunus salicina Lindl. cv. "furong") at different maturity stages to determine the most suitable maturity stage. The inhibition of plum polyphenols on xanthine oxidase (XOD) was measured, and its kinetics were studied to reveal the inhibitory mechanism. The experimental results showed that the polyphenol, flavonoid and anthocyanin contents of plums at the ripe stage were the highest, reaching 320.46 mg GAE/100 g FW, 204.21 mg/100 g FW, and 66.24 mg/100 g FW, respectively, in comparison those of the plums at the immature and mid-ripe stages. The antioxidant capacity of the ripe plums was stronger than it was during the other stages of the plums growth. Among them, the total polyphenols of the ripe plums exhibited the strongest antioxidant capacity (IC50 values against DPPH and hydroxyl radicals were 28.19 ± 0.67 μg/mL and 198.16 ± 7.55 μg/mL, respectively), which was between the antioxidant capacity of the free polyphenols and bound polyphenols. The major phenolic monomer compounds of plum polyphenols were flavan-3-ols (epicatechin, catechin, proanthocyanidin, and procyanidin B2), flavonols (myricetin), and phenolic acids (chlorogenic acid, ferulic acid, and protocatechuic acid). Additionally, plum polyphenols exhibited a strong inhibitory effect on XOD, with an IC50 value of 77.64 μg/mL. The inhibition kinetics showed that plum polyphenols are mixed-type inhibitors that inhibit XOD activity and that the inhibition process is reversible. The calculated values of Ki and α were 16.53 mmol/L and 0.26, respectively.

Correlation of Elemental Transfer, Bioactive Compounds and Antioxidant Activity on Lactuca sativa L. Grown in Soil with Functionalized CNT and HMs.

While heavy metals (HM) have been considered in recent decades to be the most common and problematic pollutants, the expansion of the list of pollutants due to the active use of carbon nanotubes (CNT) raises new questions about the benefit and harm of HM released to nature individually or fixed on CNT walls. A pot experiment was conducted to compare the effect of two classes of potential pollutants-metal salts of Pb, Mn, Cu, Zn, Cd, and Ni; and functionalized CNTs with COOH, MnO2, Fe3O4, and MnO2-Fe3O4-applied in soil, on the elemental transfer, the bioactive compounds accumulation, and the antioxidant activity in lettuce. While CNTs mainly increased the elemental transfer from soil to leaves, HM salts strongly obstructed it. In the presence of CNTs, the antioxidant activity in lettuce leaves correlated with the transfer of elements from soil to root and from root to leaves. The excess of HMs in soil induced a greater variation of the polyphenols quantity and antioxidant activity than the excess of CNTs. It might be assumed that lettuce perceived HMs as a more aggressive stressor than CNTs and more strongly activated the defense mechanism, showing the reduction of the element transfer and enhancing of total polyphenol production and antioxidant activity.

Fruit and vegetable by-products as source of bioactive compounds to preserve handmade fresh pasta

Pomegranate peels, broccoli and olive oil by-products were respectively added to pasta formulation at 3%, 5% and 8% (w/w), to compare their effects on the shelf life. Microbiological and sensory quality, pH and moisture content were assessed. Polyphenol compounds, flavonoids and antioxidant activity were also measured on both by-products and fortified tagliatelle. The difference between the shelf life of each fortified sample and that of the relative control pasta was indicated as Δ shelf life. Results demonstrated that all the investigated by-products had a positive effect on pasta preservation, with the pomegranate peel powder as the most effective. Shelf life increased as the by-product concentration increased. Δ shelf life were 0.98, 2.41 and 7.42 days for 3%, 5% and 8% pomegranate peels, respectively; −0.07, 1.52, 5.76 days for 3%, 5% and 8% broccoli by-products, respectively; −0.37, 2.08, 3.98 days for 3%, 5% and 8% olive oil by-products, respectively. Results from chemical characterization confirmed the presence of a bigger content of polyphenols and flavonoids and a higher antioxidant activity in pomegranate powder compared to broccoli and olive oil by-products. An interesting correlation was also found between the antioxidant activity and the Δ shelf life for each type of by-products.

Stachys Species: Comparative Evaluation of Phenolic Profile and Antimicrobial and Antioxidant Potential.

This study aimed to investigate the polyphenolic composition and antioxidant and antimicrobial potential of six Romanian Stachys species: S. officinalis, S. germanica, S. byzantina, S. sylvatica, S. palustris, and S. recta. The LC-MS/MS method was used to analyze the polyphenolic profile, while the phenolic contents were spectrophotometrically determined. The antioxidant activity was evaluated using the following methods: DPPH, FRAP, nitrite-induced autooxidation of hemoglobin, inhibition of cytochrome c-catalyzed lipid peroxidation, and electron paramagnetic resonance spectroscopy. The in vitro antimicrobial properties were assessed using agar-well diffusion, broth microdilution, and antibiofilm assays. Fifteen polyphenols were identified using LC-MS and chlorogenic acid was the major component in all the samples (1131.8-6761.4 μg/g). S. germanica, S. palustris, and S. byzantina extracts each displayed an intense antiradical action in relation to high contents of TPC (6.40 mg GAE/mL), flavonoids (3.90 mg RE/mL), and caffeic acid derivatives (0.89 mg CAE/mL). In vitro antimicrobial and antibiofilm properties were exhibited towards Candida albicans, Gram-positive and Gram-negative strains, with the most intense efficacy recorded for S. germanica and S. byzantina when tested against S. aureus. These results highlighted Stachys extracts as rich sources of bioactive compounds with promising antioxidant and antimicrobial efficacies and important perspectives for developing phytopharmaceuticals.

The Antibacterial Properties of Polish Honey against Streptococcus mutans-A Causative Agent of Dental Caries.

Streptococcus mutans is considered the main pathogen responsible for dental caries, one of the major infectious diseases, affecting more than 4 billion people worldwide. Honey is a natural product with well-known antibacterial potential against several human pathogens. The aim of the study was to evaluate the antibacterial efficacy of Polish honey against S. mutans and analyze the role of some bioactive substances on its antibacterial action. The antibacterial potential of different honey varieties (goldenrod, buckwheat, honeydew, and lime) was analyzed using a microdilution assay. Manuka and artificial honey were used as controls. The content of GOX, hydrogen peroxide, total polyphenols, and antioxidant potential was assayed in honey. The influence of catalase and proteinase K on antibacterial activity as well as antibiofilm action was also determined. The strongest antibacterial activity was observed for buckwheat, honeydew, and manuka honey, which were also characterized by the highest antioxidant activity and polyphenols content. Catalase treatment decreases the antibacterial activity of honey, while proteinase K treatment influences the antibacterial potential of honey slightly less. Obtained results suggest that honey can be a good natural product against S. mutans, and hydrogen peroxide was identified as a crucial contributor to its antimicrobial action.