Pro-oxidant Effects Research Articles

Effect of lyophilized plant aqueous extracts on pH, colour and myoglobin in rabbit meat during refrigerated and frozen storage

The effect of the treatment with lyophilized antioxidant extracts of wild basil (Clinopodium vulgare L.) and basil (Ocimum basilicum L.) in rabbit meat on pH, colour and myoglobin changes during refrigerated and frozen storage was investigated. The experimental design included 3 groups of meat – one control and two treated with lyophilized plant extracts (in amount 1:100). The meat was derived from three carcass parts- loin, hind leg and fore leg The meat samples were stored at 4°C for 7 days, after that the storage proceeded for 90 days at -45°C. The study demonstrated different effect of the plant antioxidants on pH and colour, as well as the changes in the myoglobin and its redox forms that depended on the carcass part. The values of pH and decreased during frozen storage. The treatment with plant extracts and storage led to considerable discoloration of the meat from hind leg and fore leg, displayed by decrease of the redness, corresponding to lower percentage of OMb but higher of MetMb. The results suggest certain pro oxidative effect of the plant extracts in this study and require further research with different doses, storage times and temperatures in order to determine the optimal antioxidant application.

Inorganic additives in meat production and processing

The present research focuses on the different ways that inorganic chemicals can affect processed meat quality and its impact on the Finial food quality. The processed meat products (ham, bacon, frankfurters, sausages, salami, and so on) are treated with food additives to increase its shelf life and/or taste (curing, smoking, salting, or the application of chemical preservatives and additives). One area of focus is the preservation and extension of shelf life and other area is to identify the effects and benefits. By incorporating natural additives, such as essential oils and plant extracts, through nano systems, antioxidant effects and improved properties have been observed when applied directly to meat or during manufacturing processes. Additionally, the general trend is a decrease in the level of sodium chloride of processed meat products. Many studies have looked into the use of NaCl substitutes to limit the pro-oxidant effects and control microbial development, including Potassium Chloride (KCl), K-lactate, Calcium Chloride (CaCl2) and Magnesium Chloride (MgCl2) microspheres and it should be governed to minimise and control the use of inorganic substances to reduce impact to the consumers.

Impact of antioxidants on PM2.5 oxidative potential, radical level, and cytotoxicity

Antioxidants are typically seen as agents that mitigate environmental health risks due to their ability to scavenge free radicals. However, our research presents a paradox where these molecules, particularly those within lung fluid, act as prooxidants in the presence of airborne particulate matter (PM2.5), thus enhancing PM2.5 oxidative potential (OP). In our study, we examined a range of antioxidants found in the respiratory system (e.g., vitamin C, glutathione (GSH), and N-acetylcysteine (NAC)), in plasma (vitamin A, vitamin E, and β-carotene), and in food (tert-butylhydroquinone (TBHQ)). We aimed to explore antioxidants' prooxidant and antioxidant interactions with PM2.5 and the resulting OP and cytotoxicity. We employed OH generation assays and electron paramagnetic resonance assays to assess the pro-oxidative and anti-oxidative effects of antioxidants. Additionally, we assessed cytotoxicity interaction using a Chinese hamster ovary cell cytotoxicity assay. Our findings revealed that, in the presence of PM2.5, all antioxidants except vitamin E significantly increased the PM2.5 OP by generating more OH radicals (OH generation rate: 0.16–24.67 pmol·min−1·m−3). However, it's noteworthy that these generated OH radicals were at least partially neutralized by the antioxidants themselves. Among the pro-oxidative antioxidants, vitamin A, β-carotene, and TBHQ showed the least ability to quench these radicals, consistent with their observed impact in enhancing PM2.5 cytotoxicity (PM2.5 LC50 reduced to 91.2 %, 88.8 %, and 75.1 % of PM2.5's original level, respectively). Notably, vitamin A and TBHQ-enhanced PM2.5 OP were strongly associated with the presence of metals and organic compounds, particularly with copper (Cu) contributing significantly (35 %) to TBHQ's pro-oxidative effect. Our study underscores the potential health risks associated with the interaction between antioxidants and ambient pollutants.

Dual Effect of Carnosine on ROS Formation in Rat Cultured Cortical Astrocytes.

Carnosine is composed of β-alanine and L-histidine and is considered to be an important neuroprotective agent with antioxidant, metal chelating, and antisenescence properties. However, children with serum carnosinase deficiency present increased circulating carnosine and severe neurological symptoms. We here investigated the in vitro effects of carnosine on redox and mitochondrial parameters in cultured cortical astrocytes from neonatal rats. Carnosine did not alter mitochondrial content or mitochondrial membrane potential. On the other hand, carnosine increased mitochondrial superoxide anion formation, levels of thiobarbituric acid reactive substances and oxidation of 2',7'-dichlorofluorescin diacetate (DCF-DA), indicating that carnosine per se acts as a pro-oxidant agent. Nonetheless, carnosine prevented DCF-DA oxidation induced by H2O2 in cultured cortical astrocytes. Since alterations on mitochondrial membrane potential are not likely to be involved in these effects of carnosine, the involvement of N-Methyl-D-aspartate (NMDA) receptors in the pro-oxidant actions of carnosine was investigated. MK-801, an antagonist of NMDA receptors, prevented DCF-DA oxidation induced by carnosine in cultured cortical astrocytes. Astrocyte reactivity induced by carnosine was also prevented by the coincubation with MK-801. The present study shows for the very first time the pro-oxidant effects of carnosine per se in astrocytes. The data raise awareness on the importance of a better understanding of the biological actions of carnosine, a nutraceutical otherwise widely reported as devoid of side effects.

Ceria-Based Nanozymes in Point-of-Care Diagnosis: An Emerging Futuristic Approach for Biosensing.

In recent years, there has been a notable increase in interest surrounding nanozymes due to their ability to imitate the functions and address the limitations of natural enzymes. The scientific community has been greatly intrigued by the study of nanoceria, primarily because of their distinctive physicochemical characteristics, which include a variety of enzyme-like activities, affordability, exceptional stability, and the ability to easily modify their surfaces. Consequently, nanoceria have found extensive use in various biosensing applications. However, the impact of its redox activity on the enzymatic catalytic mechanism remains a subject of debate, as conflicting findings in the literature have presented both pro-oxidant and antioxidant effects. Herein, we creatively propose a seesaw model to clarify the regulatory mechanism on redox balance and survey possible mechanisms of multienzyme mimetic properties of nanoceria. In addition, this review aims to showcase the latest advancements in this field by systematically discussing over 180 research articles elucidating the significance of ceria-based nanozymes in enhancing, downsizing, and enhancing the efficacy of point-of-care (POC) diagnostics. These advancements align with the ASSURED criteria established by the World Health Organization (WHO). Furthermore, this review also examines potential constraints in order to offer readers a concise overview of the emerging role of nanoceria in the advancement of POC diagnostic systems for future biosensing applications.

Phytochemical analysis of carotenoid profile in Mentha piperita and Artemisia vulgaris: cytotoxicity in tumoral cells and evaluation of plasmid DNA cleavage

ABSTRACT Several medicinal plants have been administered to cancer patients attributed to their anticarcinogenic and chemoprotective properties, in addition to lower toxicity compared to traditional therapies. The aim was to investigate the antioxidant properties and carotenoid composition of aqueous extracts of Mentha piperita or Artemisia vulgaris which were previously found to exert beneficial effects on human health through diet. aqueous extracts exhibited potent antioxidant activity. A diversity of carotenoids was identified in these extracts using HPLC-PDA-MS/MS. Both extracts contained predominantly all-trans-lutein as the main component within this class. In order to investigate antioxidant properties, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) techniques were used. The (3–4,5 dimethylthiazol-2, 5 diphenyl tetrazolium bromide) (MTT) and Crystal Violet assays assessed cellular cytotoxicity. Assessments of presence of reactive species were carried out following exposure of oral squamous cell carcinoma cell line (SCC-4) to various aqueous extracts of M piperita or A vulgaris utilizing dichlorofluorescein diacetate (DCFH-DA) and nitric oxide (NO) assays. Exposure to these extracts induced severe cytotoxic effects, which led to investigation of the biochemical and molecular mechanisms underlying this observed effect. Data demonstrated that both solutions induced oxidative stress and DNA damage, especially at higher concentrations using agarose gel subjected to electrophoresis. It is known that exposure to excess amounts of antioxidants results in a prooxidant effect which is beneficial in cancer therapy. Further, the extracts were found to reduce viability of SCC-4 in culture, indicating that this antitumoral activity may be of therapeutic importance and requires further study.

Plant extracts modulate cellular stress to inhibit replication of mouse Coronavirus MHV-A59

The Covid-19 infection outbreak led to a global epidemic, and although several vaccines have been developed, the appearance of mutations has allowed the virus to evade the immune response. Added to this is the existing risk of the appearance of new emerging viruses. Therefore, it is necessary to explore novel antiviral therapies. Here, we investigate the potential in vitro of plant extracts to modulate cellular stress and inhibit murine hepatitis virus (MHV)-A59 replication. L929 cells were treated with P2Et (Caesalpinia spinosa) and Anamu SC (Petiveria alliacea) plant extracts during infection and virus production, ROS (reactive oxygen species), UPR (unfolded protein response), and autophagy were assessed. P2Et inhibited virus replication and attenuated both ROS production and UPR activation induced during infection. In contrast, the sustained presence of Anamu SC during viral adsorption and replication was required to inhibit viral infection, tending to induce pro-oxidant effects, and increasing UPR gene expression. Notably, the loss of the PERK protein resulted in a slight decrease in virus yield, suggesting a potential involvement of this UPR pathway during replication. Intriguingly, both extracts either maintained or increased the calreticulin surface exposure induced during infection. In conclusion, our findings highlight the development of antiviral natural plant extracts that differentially modulate cellular stress.

Studying the Functional Potential of Ground Ivy (Glechoma hederacea L.) Extract Using an In Vitro Methodology

Glechoma hederacea L., known as ground ivy, has a long history of use in folk medicine. The main bioactive compounds in ground ivy are polyphenolic compounds known for their potent antioxidant and antimicrobial activities and thus have high potential as functional ingredients against bacterial infections and the occurrence of chronic diseases associated with oxidative stress in the human body. The aim of the present study was to determine the biological activity of ground ivy extract on selected human cell lines, including hepatic (HepG2), tongue (CAL 27), gastric (AGS) and colon (Caco-2) cancer cell lines by evaluating cytotoxicity, formation of reactive oxygen species and genotoxicity. The antioxidant capacity of the extract was additionally evaluated using cellular model macromolecules of protein and DNA, bovine serum album and plasmid phiX174 RF1 DNA. The effect of ground ivy extract on representatives of human microflora, including L. plantarum, E. coli and S. aureus, was also studied. The cytotoxicity of the extract depended on the type of cells treated, and the pro-oxidant effect generally decreased with increasing exposure time. The most pronounced genoprotective effect against hydroxyl radical damage was monitored in model plasmid DNA and occurred at the highest tested concentration (0.25 mg mL−1), with 95.89% preservation of the supercoiled form of the plasmid. This concentration also had the most significant antioxidant activity on the model protein—14.01% more than the positive control prepared using Trolox. The ground ivy extract showed high antimicrobial potential against the pathogenic bacteria E. coli and S. aureus.

The prooxidant effect of natural antioxidants combination when co‐encapsulated to chia oil‐based nutraceutical edible powders: More is not always better

AbstractChia oil (CO) is the vegetable source with the highest ω − 3 polyunsaturated fatty acids (PUFAs) proportion known to date (61%–70%). Although this is favorable from a nutritional point of view, higher contents of ω − 3 PUFAs result in shorter shelf life and poorer oxidative stability. The objective of this work was to design edible oil powders of CO co‐encapsulated with commercial antioxidant‐rich sources—containing β‐carotene (BC), astaxanthin (ASX), and vitamin E (VE), either alone or combined (BC–VE and ASX–VE)—to prolong its oxidative stability. To carry out this, spray‐dried microcapsules were produced through oil‐in‐water double‐layered emulsions using whey proteins and pectin. Spray‐dried capsules were stored at 4 and 30°C, and weekly determinations of primary and secondary oxidation compounds were carried out, by measuring peroxide value (PV) and thiobarbituric reactive substances. CO microcapsules with just one commercial antioxidant‐rich source played a key role to keep oxidative indicators below recommended limits (PV < 15 meq kg−1 oil) when storing powders at 30°C, being ASX the best option, whereas there was no significant effect in oxidation when stored at 4°C. Nevertheless, when combining commercial antioxidant sources (BC–VE and ASX–VE), a marked prooxidant effect was observed, exceeding PV threshold at both temperatures after 2 months of storage.Practical Applications: Combination of chia oil and natural antioxidant commercial sources in edible powders constitutes a promising commodity to design potentially anti‐inflammatory nutritional interventions to prevent chronic noncommunicable diseases. This study contributes to show that mixing different antioxidants with chia oil might have a detrimental effect on oil oxidative stability during storage, so caution must be applied when formulating this type of functional ingredients as more is not always better. The goal of this contribution is that it was possible to obtain an easy‐to‐handle powder nutraceutical ingredient containing both chia oil and astaxanthin (using antioxidant concentrations that might have a significant effect on human health) that could be stored at 30°C up to 8 weeks, keeping oxidative indicators below the limits recommended by Codex Alimentarius (peroxide value <15 meq kg−1 oil).

The power of the QUENCHER method in measuring total antioxidant capacity of foods: Importance of interactions between different forms of antioxidants

Antioxidants play a crucial role in maintaining human health by counteracting oxidative stress and regulating redox balance within the body. The mixture of various antioxidant compounds in different forms (i.e., free, bound, insoluble) in food creates a redox active environment both in the human body and in the food system. Acting as both electron donors and acceptors while interacting with each other can either result in antagonism through pro-oxidative effects, or synergism through regeneration of one antioxidant by another. During the antioxidant capacity measurement, besides the individual antioxidant effects of the antioxidant components, these effects that occur because of their interaction with each other should be also considered. Classical antioxidant capacity measurement methods mostly concentrate on the fractions of foods that can be extracted with either water, alcohol, lipid, or acid/alkaline solutions. Antioxidants that cannot be extracted with any solvent are mostly ignored in these methods. On the other hand, the QUENCHER method, which allows direct measurement of antioxidant capacity foods without extraction, offers a rational solution to the limitations of traditional extraction-based methods. This approach considers the antioxidant capacity and interactions of all antioxidant forms that can be found in a food matrix, at the same time. This review provides detailed insights into the advantages of QUENCHER as a holistic approach for the accurate measurement of the antioxidant capacity of foods.

Effects of including of Japanese Pumpkin Seeds and Pomace in the Diets of Pacific White Shrimp (Penaeus vannamei).

A 60-day feeding trial was conducted to evaluate the effects of including pumpkin seeds and pomace in the diets of Pacific white shrimp Penaeus vannamei, and the effects of these supplements on growth performance, body composition, and total polyphenol, flavonoid and carotenoid contents, as well as on total antioxidant activity, and body color parameters. Five diets were evaluated: pumpkin seeds (PS) at 50 and 100 g·kg-1, pumpkin pomace (PP) at 50 and 100 g·kg-1, and a control treatment. Pacific white shrimp (P. vannamei) juveniles (0.60 ± 0.01 g) were stocked in 15 tanks (310 L), containing 30 shrimps per tank, and the treatments were randomly distributed in triplicate. At the end of the experiment, shrimps were euthanized, weighed, and dissected for further analyses. The inclusion of PS in the diets impaired growth performance, reduced the total flavonoid content and had a pro-oxidative effect on muscle. The inclusion of PP in the diets did not affect growth performance, improved the feed conversion ratio, increased the total flavonoid content in the diets and hepatopancreas, and improved the antioxidant activity of the feeds and shrimp muscle. The total carotenoid content of the feeds increased with the inclusion of PS or PP in the diets; however, the total carotenoid content of shrimp increased only in those fed PP diets. Shrimp fed with PS diets showed a yellowish color and higher saturation when fresh and a reddish color and yellow hue angle after cooking. Shrimp fed PP diets turned reddish and yellowish, both when fresh and after cooking. The inclusion of PS in P. vannamei diets is not recommended; however, PP can be included at 100 g·kg-1 without affecting the growth parameters. Further studies evaluating the inclusion of higher PP levels in shrimp diets are recommended.

New Insights into the Loss of Antioxidant Effectiveness of Phenolic Compounds in Vegetable Oils in the Presence of Phosphatidylcholine.

It has been proposed that lipid oxidation reactions in edible oils primarily occur in reverse micelles (RM) of amphiphilic components. While the prooxidative effect of RM has been demonstrated, the mechanism involved is not fully understood. Both reductions and enhancements in the antioxidant efficacy (AE) of α-tocopherol and Trolox have been observed in different studies when phosphatidylcholine (PC) was added and PC RM were formed. However, most of these investigations employed lipid systems consisting of stripped vegetable oil diluted in saturated medium-chain triacylglycerols (MCT) and utilized antioxidant concentrations well below those found in edible oils. These two specific factors were investigated in the present study. The effect of RM of purified egg yolk PC on the AE of 1.16 mmol kg-1 α-tocopherol or Trolox in stripped sunflower oil (SSO) was studied by the Rancimat (100 °C) and oven (50 °C) tests. Increasing PC concentrations (50-1000 ppm) had no significant impact on α-tocopherol, but substantial reductions in AE were observed for Trolox. This phenomenon may be attributed to the partitioning of Trolox into the pre-existing PC micelles, suggesting that primary oxidation reactions occurred in the continuous lipid phase. In addition, the effectiveness of both antioxidants decreased significantly in the presence of PC when a low antioxidant concentration (0.06 mmol kg-1) was assayed in SSO:MCT (1:3, w/w).

CTNI-27. TRIAL IN PROGRESS A PHASE 2 STUDY OF BPM 31510 (AN OXIDIZED COQ10-LIPID CONJUGATE NANODISPERSION) WITH VITAMIN K AND STANDARD CHEMORADIATION IN NEWLY DIAGNOSED GLIOBLASTOMA

Abstract INTRODUCTION: BPM 31510 is a novel drug-lipid conjugate nanodispersion that significantly increases the bioavailability of ubidecarenone (oxidized CoQ10). Supraphysiological concentrations of CoQ10 have been shown to have a paradoxical pro-oxidant effect on a variety of malignant cells while not altering the metabolic phenotype in normal cells. Glioblastoma multiforme (GBM) is a metabolically active cancer that is reliant on mechanisms of redox homeostasis to avert reactive oxygen species (ROS)-triggered apoptosis. This trial investigates whether this susceptibility of GBM metabolism may be effectively targeted by the potentially synergistic combination of BPM 31510 and standard-of-care radiotherapy, a known producer of ROS. Early-phase trials of BPM 31510 have shown a favorable safety profile with primarily hepatotoxicity and coagulopathy, the latter of which is mitigated by co-administration of Vitamin K. TRIAL DESIGN: BPM 31510IV-11 (NCT04752813) is a single-arm multicenter phase 2 study of BPM 31510 + Vitamin K1 in combination with standard chemoradiation for newly diagnosed GBM. Eligible patients have GBM with no prior therapy, and those with recent hemorrhage, coagulopathy, or who require anticoagulation are excluded. BPM 31510 starts 2-4 weeks after biopsy or resection initially as monotherapy for 2 weeks followed by an additional 6 weeks in combination with temozolomide-based chemoradiation. To assess safety of BPM 31510 with concomitant chemoradiotherapy, this study begins with a dose confirmation phase and allows for one dose reduction in the event of a DLT. The starting dose of BPM 31510 is 110 mg/kg administered as a continuous infusion over 96-hours weekly. The primary endpoint is 6-month progression-free survival (PFS6) by RANO criteria. Secondary endpoints include overall survival and safety. Approximately 50 patients will be enrolled for 90% power in rejecting the null hypothesis of PFS6 ≤ 30%. The study is enrolling at two US sites with a third opening soon.

Modulatory effect of pomegranate peel extract on key regulators of ovarian cellular processes in vitro.

In this study, response of ovarian cells (human granulosa cell line HGL5, and human adenocarcinoma cell line OVCAR-3) to short-term pomegranate peel extract (PPE) treatment (for 24 hours in cell culture) was evaluated in vitro. Quantitative and qualitative screening of polyphenols revealed punicalagins α and β as major polyphenolic components. Total phenolic content (TPC) was 93.76 mg GAE/g d.w. with a high antioxidant activity of 95.30 mg TEAC/g d.w. In OVCAR-3, PPE treatment inhibited the metabolic activity, and increased cyclin-dependent kinase 1 (CDKN1A, p21) level at the highest dose, but not in HGL5. Flow cytometry analysis could not detect any significant difference between proportions of live, dead, and apoptotic cells in both cell lines. Reactive oxygen species (ROS) revealed an antioxidant effect on HGL5, and a prooxidant effect by stimulating ROS generation in OVCAR-3 cells at the higher doses of PPE. However, in contrast to HGL5, PPE treatment decreased release of growth factors - TGF-β2 and EGF at the highest dose, as well as their receptors TGFBR2 and EGFR in OVCAR-3 cells. PPE also influenced steroidogenesis in granulosa cells HGL5 by stimulating 17β-estradiol secretion at higher doses. In conclusion, the present study highlighted the bioactive compounds in pomegranate peels and the possible mechanisms of action of PPE, shedding light on its promising role in ovarian cancer (chemo)prevention and/or management.

Incorporation of Pectin into Vaterite Microparticles Prevented Effects of Adsorbed Mucin on Neutrophil Activation

The application of vaterite microparticles for mucosal delivery depends on their interaction with mucin and immune cells. As we have shown previously, the binding of mucin onto particles enhances the generation of reactive oxygen species by neutrophils. The attenuation of the pro-oxidant effect of the bound mucin through the modification of vaterite could improve its biocompatibility. Hybrid microparticles composed of vaterite and pectin (CCP) were prepared using co-precipitation. In comparison with vaterite (CC), they had a smaller diameter and pores, a greater surface area, and a negative zeta-potential. We aimed to study the cytotoxicity and mucin-dependent neutrophil-activating effect of CCP microparticles. The incorporated pectin did not influence the neutrophil damage according to a lactate dehydrogenase test. The difference in the CC- and CCP-elicited luminol or lucigenin chemiluminescence of neutrophils was insignificant, with no direct pro- or antioxidant effects from the incorporated pectin. Unlike soluble pectin, the CCP particles were ineffective at scavenging radicals in an ABAP–luminol test. The fluorescence of SYTOX Green demonstrated a CCP-stimulated formation of neutrophil extracellular traps (NETs). The pre-treatment of CC and CCP with mucin resulted in a 2.5-times-higher CL response of neutrophils to the CC-mucin than to the CCP-mucin. Thus, the incorporation of pectin into vaterite microspheres enabled an antioxidant effect to be reached when the neutrophils were activated by mucin-treated microparticles, presumably via exposed ligands.

Role of Vitamins in Cardiovascular Health: Know Your Facts-Part 2.

Cardiovascular disease (CVD) is a major cause of morbidity/mortality world-wide, hence preventive interventions are crucial. Observational data showing beneficial CV effects of vitamin supplements, promoted by self-proclaimed experts, have led to ~50% of Americans using multivitamins; this practice has culminated into a multi-billion-dollar business. However, robust evidence is lacking, and certain vitamins might incur harm. This two-part review focuses on the attributes or concerns about specific vitamin consumption on CVD. The evidence for indiscriminate use of multivitamins indicates no consistent CVD benefit. Specific vitamins and/or combinations are suggested, but further supportive evidence is needed. Data presented in Part 1 indicated that folic acid and certain B-vitamins may decrease stroke, whereas niacin might raise mortality; beta-carotene mediates pro-oxidant effects, which may abate the benefits from other vitamins. In Part 2, data favor the anti-oxidant effects of vitamin C and the anti-atherogenic effects of vitamins C and E, but clinical evidence is inconsistent. Vitamin D may provide CV protection, but data are conflicting. Vitamin K appears neutral. Thus, there are favorable CV effects of individual vitamins (C/D), but randomized/controlled data are lacking. An important caveat regards the potential toxicity of increased doses of fat-soluble vitamins (A/D/E/K). As emphasized in Part 1, vitamins might benefit subjects who are antioxidant-deficient or exposed to high levels of oxidative-stress (e.g., diabetics, smokers, and elderly), stressing the importance of targeting certain subgroups for optimal results. Finally, by promoting CV-healthy balanced-diets, we could acquire essential vitamins and nutrients and use supplements only for specific indications.

Characterization of phenolic components of black teas of different origins and the effect of brewing duration on quality properties.

This research aims to identify the phytochemical constituents of 79 different samples of black tea, including varieties from India, Iran (IrT), Turkey (TT), and Sri Lanka. In addition, this study investigates the effect of varying brewing times on the quality characteristics of tea. Therefore, we analyzed the phytochemical content of tea using a novel LC-MS/MS method that we developed, which identifies 53 different phenolic compounds. Furthermore, objective evaluations were conducted on the total phenolic compound, total flavonoid compound, antioxidant activity, and color values at 15, 30, and 60-min brewing intervals. The prevailing phenolic compounds discovered in the corresponding tea classifications were quantitatively analyzed to be quinic acid, epicatechin gallate, epigallocatechin gallate, epicatechin, epigallocatechin, gallic acid, nicotiflorine, and isoquercitrin. The study found that the TT and IrT groups had the richest phytochemical content and the highest antioxidant activity. The Turkish tea group had the highest measurement for the desired red color, which is considered a sensory property. Infusion color, antioxidant activity, and total phenolic and flavonoid contents showed significant increases with prolonged brewing time. It was important to note that the chemical composition of tea varies according to its origin and brewing conditions. Extending the brewing time improved the quality of the tea. It should be noted, however, that longer brewing times result in a more intense release of flavonoids, and this increase may have a pro-oxidant effect.

Design, synthesis, characterization of ferulic acid and p-coumaric acid amide derivatives as an antibacterial/antioxidant agent

Ferulic acid and p-coumaric acid, cinnamic derivatives of phenolic acid, have antibacterial, prooxidant, and antioxidant effects. In this study ferulic acid and p-coumaric acid amide derivatives were investigated for their antibacterial and antioxidant properties are described in this communication. The most effective conjugates against B subtilis were 5b (IC50: 215 ​± ​1.3 ​μM) and 4d (IC50: 336 ​± ​2.7 ​μM) and against P. aeruginosa were 4b (IC50: 365 ​± ​2.8 ​μM) and 5b (IC50: 341 ​± ​3.6 ​μM), whereas the none of conjugates were more effective against E. coli than reference Kanamycin. Conjugates 5b was the most effective against B subtilis of all the synthesized conjugates, with IC50 values of (IC50: 215 ​± ​1.3 ​μM). The free radical scavenging capacity of each compound was determined using the DPPH and ABTS assays. Conjugates 4b (IC50: 53 ​± ​3.6 ​μM), 4c (IC50: 58 ​± ​1.3 ​μM), 4d (IC50: 57 ​± ​2.5 ​μM), 5b (IC50: 29 ​± ​1.5 ​μM) and 4a (IC50: 56 ​± ​4.3 ​μM) have greater antioxidant capacity than ferulic acid and ascorbic acid in the DPPH assay. Whereas in the ABTS assay, compounds 4b (IC50: 7 ​± ​1.8 ​μM), 5b (IC50: 5 ​± ​0.7 ​μM), 4a (IC50: 9 ​± ​3.2 ​μM), 4g (IC50: 7 ​± ​2.3 ​μM), and 5a (IC50: 8 ​± ​4.3 ​μM) showed more antioxidant activity than ferulic acid, p-coumaric acid and ascorbic acid. Thus, a large library of compounds derived from bile acid can be easily synthesized for extensive structure-activity relationship studies in order to identify the most appropriate antibacterial and antioxidant agents.

The Association between Oxidative Balance Score and Urinary Levels of 8-Hydroxydeoxyguanosine among Japanese Adults.

The oxidative balance score (OBS), wherein higher OBSs indicate lower oxidative stress, was designed to assess a composite measure of multiple pro-oxidant and antioxidant effects on an individual's oxidative stress status. This study aimed to evaluate whether OBSs were inversely associated with urinary levels of 8-hydroxydeoxyguanosine (8-OHdG)-an oxidative stress marker-among Japanese adults. This cross-sectional study was based on data obtained during 2010-2012. Overall, 7552 participants from the J-MICC Study Saga who answered a self-administered food frequency questionnaire were recruited for the final analysis. OBSs were calculated from 11 pro-oxidant and antioxidant lifestyle factors, including dietary intake, physical activity, and alcohol and smoking status. Urinary 8-OHdG values were corrected by creatinine level (ng/mg creatinine). Our findings revealed a higher total OBS was significantly associated with lower urinary 8-OHdG/creatinine levels after adjustment for covariates in men and women (p for trend < 0.01 in both sexes). We performed a multiple regression analysis of the association between OBSs and urinary 8-OHdG/creatinine levels stratified by age, body mass index (BMI), and menopausal status and found consistent negative associations in most groups for both sexes. No significant differences in the 60-64 age group for women (standardized β = -0.09, p = 0.13) or BMI < 18.5 kg/m2 for men (standardized β = -0.18, p = 0.17) were observed. A higher OBS had a strong inverse association with urinary 8-OHdG/creatinine levels in men and women among Japanese adults. The OBS might be a useful tool for evaluating the roles of oxidative stress-related lifestyle factors, including diet.

Evaluation of natural extracts’ antioxidant capacity for controlling fresh sausage oxidation

Lipid oxidation impacts the quality and shelf life of meat products. The use of natural antioxidants is an alternative to delay their oxidative deterioration. This study aimed to determine the antioxidant activity of natural extracts and evaluate the viability of replacing 2,3-tert-butyl-4-hydroxyanisole (BHA) in fresh sausages. Both tocopherols and grape seed extract showed similar antioxidant activity to BHA through the 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical (DPPH) and ferric reducing antioxidant power (FRAP) methods. The effectiveness of these antioxidants applied to fresh sausage was evaluated during 15 days of storage at 4.0ºC under light incidence. The results indicated a pro-oxidant effect of grape seed extract (with 6.74% acidity and 2.74 mg MDA kg sample-1 thiobarbituric acid reactive substances (TBARS)) and showed the viability of replacing BHA with tocopherols. Tocopherols had a lower peroxide value (3.07 mE O2 kg-1) than the control (11.40 mE O2 kg-1), with no difference in TBARS or acidity content compared to BHA, and the lowest total mass loss (18.22%).