Thiobarbituric Acid Reactive Substances Assay Research Articles

Comparative Preservative Potential of Essential Oils of Ocimum gratissimum from Bambili of the North West and Mbonge of the South West Regions of Cameroon on Scomber scombrus

Essential oils serve as a natural alternative to chemical or synthetic antimicrobials and antioxidants to fight against food borne pathogens or spoilage organisms, inhibiting lipid peroxidation and extending the shelf life of fish and other seafood. This study examines the antibacterial properties of essential oils from leaves of Ocimum gratissimum L. from two localities of the North West and South West of Cameroon on some pathogenic spoilage gram negative and positive bacteria isolated from mackerel, and their antimicrobial and antioxidant effectiveness on the fish quality during preservation for one month at -18oC. The plant materials were harvested from Bambili, the North West Region of Cameroon and from Mbonge, the South West Region of Cameroon and the essential oils extracted by hydro-distillation using Clevenger-type apparatus. Escherichia coli, Salmonella typhi and Staphylococcus aereus were isolated from mackerel by culture techniques and their susceptibility to the essential oils determined by well diffusion method. Psychrophilic bacteria and Enterobacteraceae counts were used to evaluate the microbiological quality of the fish during storage. Total volatile basic nitrogen and thiobarbituric acid reactive substance assays were used as indices to assess the biochemical quality of the fish during storage. Antibacterial susceptibility test showed that essential oils of O. gratissimum from the North West and South West Regions were active on all the tested microorganisms with different degree.The inhibitory diameters for essential oil from the South West Region were 28.0 mm, 27.2 mm and 26.0 mm while that for essential oil from the Bambili were 24.1 mm, 20.4mm and 21.9 mm for Staphylococcus aereus, Escherichia coli and Salmonella typhi respectively. At the end of storage periods, the values of Psychrotrophs plate counts, total volatile base nitrogen and thiobarbituric acid reactive substances for fish samples treated with essential oil from the Mbonge were 2.71log10cfu/g, 12.88 mgN/100g and 0.88 mgMDA/Kg, while that treated with North West essential oil were 3.00 log10cfu/g, 16.24 mgN/100g and 1.26 mgMDA/Kg respectively. From the obtained results, essential oil of O. gratissimum from the Mbonge was the most effective in preserving Atlantic mackerel.

Potential Antioxidant and Anti-Inflammatory Effects of Spilanthes acmella and Its Health Beneficial Effects: A Review.

Oxidative stress and inflammation are two common risk factors of various life-threatening disease pathogenesis. In recent years, medicinal plants that possess antioxidant and anti-inflammatory activities were extensively studied for their potential role in treating and preventing diseases. Spilanthes acmella (S. acmella), which has been traditionally used to treat toothache in Malaysia, contains various active metabolites responsible for its anti-inflammatory, antiseptic, and anesthetic bioactivities. These bioactivities were attributed to bioactive compounds, such as phenolic, flavonoids, and alkamides. The review focused on the summarization of in vitro and in vivo experimental reports on the antioxidant and anti-inflammatory actions of S. acmella, as well as how they contributed to potential health benefits in lowering the risk of diseases that were related to oxidative stress. The molecular mechanism of S. acmella in reducing oxidative stress and inflammatory targets, such as inducible nitric oxide synthase (iNOS), transcription factors of the nuclear factor-κB family (NF-κB), cyclooxygenase-2 (COX-2), and mitogen-activated protein kinase (MAPK) signaling pathways were discussed. Besides, the antioxidant potential of S. acmella was measured by total phenolic content (TPC), total flavonid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and superoxide anion radical scavenging (SOD) and thiobarbituric acid reactive substance (TBARS) assays. This review revealed that S. acmella might have a potential role as a reservoir of bioactive agents contributing to the observed antioxidant, anti-inflammatory, and health beneficial effects.

Protective role of Clitoria ternatea L. flower extract on methylglyoxal-induced protein glycation and oxidative damage to DNA

BackgroundMethylglyoxal (MG) is a highly reactive dicarbonyl precursor for the formation of advanced glycation end products (AGEs) associated with age-related diseases, including diabetes and its complications. Clitoria ternatea L. flower has been reported to possess antioxidant and antiglycating properties. Evidence indicates that the extract of Clitoria ternatea L. flower inhibits fructose-induced protein glycation and oxidative damage to bovine serum albumin (BSA). However, there is no evidence to support the inhibitory effect of CTE against MG-mediated protein glycation and oxidative damage to protein and DNA. Therefore, the aim of the present study was to investigate whether C. ternatea flower extract (CTE) prevents MG-induced protein glycation and oxidative DNA damage.MethodsThe formation of fluorescent AGEs in BSA was evaluated using spectrofluorometer. The protein carbonyl and thiol group content were used for detecting protein oxidation. DNA strand breakage in a glycation model comprising of MG, lysine and Cu2+ or a free radical generator 2,2′-azobis(2-methylpropionamidine) dihydrochloride (AAPH) systems was investigated using gel electrophoresis. Generation of superoxide anions and hydroxyl radicals in the MG/lysine system was assessed by the cytochrome c reduction assay and thiobarbituric acid reactive substances assay, respectively. High performance liquid chromatography (HPLC) was used to measure the MG-trapping ability.ResultsIn the BSA/MG system, CTE (0.25–1 mg/mL) significantly inhibited the formation of fluorescent AGEs and protein oxidation by reducing protein carbonyl content as well as preventing the protein thiol depletion. The concentration of CTE at 0.125–1 mg/mL prevented oxidative DNA cleavage in MG/lysine and AAPH systems associated with the inhibition of superoxide anion and hydroxyl radical formation. It also directly trapped MG in a concentration-dependent manner, ranging from 15 to 43%.ConclusionsThe study findings suggest that the direct carbonyl trapping ability and the free radical scavenging activity of CTE are the underlying mechanisms responsible for the prevention of protein glycation and oxidative DNA damage.

D-4F Ameliorates Contrast Media-Induced Oxidative Injuries in Endothelial Cells via the AMPK/PKC Pathway.

Endothelial dysfunction is involved in the pathophysiological processes of contrast media (CM)–induced acute kidney injury (CI-AKI) after vascular angiography or intervention. Previous study found that apolipoprotein A-I (apoA-I) mimetic peptide, D-4F, alleviates endothelial impairments via upregulating heme oxygenase-1 (HO-1) expression and scavenging excessively generated reactive oxygen species (ROS). However, whether D-4F could ameliorate oxidative injuries in endothelial cells through suppressing ROS production remains unclear. In this study, a representative nonionic iodinated CM, iodixanol, was chosen for the in vitro and in vivo studies. Endothelial cell viability was assayed using micrographs, lactate dehydrogenase (LDH) activity, and cell counting kit-8 (CCK-8). Apoptosis was detected using flow cytometry analysis and caspase-3 activation. Endothelial inflammation was tested using monocyte adhesion assay and adhesion molecule expression. ROS production was detected by measuring the formation of lipid peroxidation malondialdehyde (MDA) through the thiobarbituric acid reactive substance (TBARS) assay. Peroxynitrite (ONOO⁻) formation was tested using the 3-nitrotyrosine ELISA kit. Iodixanol impaired cell viability, promoted vascular cell adhesion molecule-1 (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1) expression, and induced cell apoptosis in human umbilical vein endothelial cells (HUVECs). However, D-4F mitigated these injuries. Furthermore, iodixanol induced the phosphorylation of protein kinase C (PKC) beta II, p47, Rac1, and endothelial nitric oxide synthase (eNOS) at Thr495, which elicited ROS release and ONOO⁻ generation. D-4F inhibited NADPH oxidase (NOX) activation, ROS production, and ONOO⁻ formation via the AMP-activated protein kinase (AMPK)/PKC pathway. Additionally, after an intravascular injection of iodixanol in Sprague Dawley rats, iodixanol induced a remarkable inflammatory response in arterial endothelial cells, although significant apoptosis and morphological changes were not observed. D-4F alleviated the vessel inflammation resulting from iodixanol in vivo. Collectively, besides scavenging ROS, D-4F could also suppress ROS production and ONOO⁻ formation through the AMPK/PKC pathway, which ameliorated oxidative injuries in endothelial cells. Hence, D-4F might serve as a potential agent in preventing CI-AKI.

Sensory and Physicochemical Quality Characteristics of Haddock Fish Cake Enriched with Atlantic Mackerel Quality of Fish Cakes.

SUMMARYResearch backgroundIt is desirable to increase the consumption of pelagic fish rich in long-chain omega-3 fatty acids. Partial replacement of traditionally used white fish species by pelagic fish will increase the content of omega-3 fatty acids, and thus improve the nutritional value but it may also affect the consumer acceptance. The aim of this study is to assess the physicochemical and sensory quality of novel fish cake prototypes prepared from haddock and mackerel mince.Experimental approachFillets of haddock and Atlantic mackerel were used as raw material for preparation of fish cakes. The fish fillets were minced, mixed together (in haddock/mackerel mass ratio of 100:0, 75:25 and 50:50%) with salt, potato starch, pepper and full fat milk. Physicochemical and sensory analyses were further performed.Results and conclusionsThe fatty acid composition analysis showed that the recommended daily intake of 250 mg of eicosapentaenoic acid and docosahexaenoic acid can easily be reached by consumption of fish cakes enriched with mackerel. The oxidation levels of all fish cakes were low in terms of peroxide value and thiobarbituric acid reactive substance assay (TBARS). Fish cakes prepared with higher mass fraction of mackerel mince (>50%) had significantly (p<0.05) softer texture than other fish cakes due to higher amount of fat in their formulations. At the same time, these fish cakes were significantly darker than haddock-based (>50%) fish cakes due to higher myoglobin content in the fish muscle. Moreover, fish cakes with higher amount of mackerel mince had increased yellowness due to the accumulation of water-soluble (r=0.990, p<0.05) and fat-soluble (r=0.976, p<0.05) TBARS. Metabolites relevant for taste and quality were quantified by using 1H nuclear magnetic resonance (NMR) spectroscopy. The mass fraction of anserine, trimethylamine oxide and β-alanine decreased, while the mass fraction of histidine, glutamic acid and alanine increased with the addition of mackerel. Sensory tests have shown the addition of mackerel did not reduce consumer acceptability towards the new fish cakes.Novelty and scientific contributionThe research demonstrated that Atlantic mackerel can be successfully used for partial replacement of white fish species in fish cake formulations to produce healthy and tasty ready-to-cook products and increase the consumption of small pelagic fish in Europe.

Deoxynivalenol downregulates NRF2-induced cytoprotective response in human hepatocellular carcinoma (HepG2) cells

Deoxynivalenol (DON) commonly infects agricultural foods; it exhibits toxicity by inducing oxidative stress and inhibiting protein synthesis. Nuclear factor erythroid 2-related factor 2 (NRF2) regulates the cellular antioxidant response. We investigated the cytotoxicity of DON and its effect on the NRF2 antioxidant response in HepG2 cells. The Methyl Thiazol Tetrazolium (MTT), glutathione (GSH) and ATP assays evaluated toxicity, whilst lipid peroxidation and membrane damage were assessed using the Thiobarbituric acid reactive substance (TBARS) and lactate dehydrogenase (LDH) assays. Protein expression of NRF2, phosphorylated (p-ser40) NRF2, catalase (CAT), superoxide dismutase 2 (SOD2), and Sirtuin 3 (Sirt3) were quantified by Western Blotting. Gene expression of glutathione peroxidase (GPx), CAT and SOD2 was determined using qPCR. DON decreased cell viability, GSH concentrations and ATP levels and increased lipid peroxidation and membrane damage. DON significantly decreased total NRF2 and increased p-NRF2 and downregulated the transcription and translation of NRF2 target antioxidant enzymes. Further, expression of the mitochondrial stress response protein, Sirt3 was significantly decreased. In conclusion, DON induced oxidative stress and downregulated NRF2-induced cytoprotection by suppressing the antioxidant signalling mechanism in HepG2 cells.

Discrimination between minimally modified LDL and fully oxidized LDL using monoclonal antibodies

Low density lipoprotein (LDL) can be oxidized in a stepwise process that leads to the production of minimally modified low density lipoprotein (mm-LDL), in which only the lipid component is oxidized, and then of fully oxidized LDL (oxLDL), in which both the lipids and the protein are oxidized. The thiobarbituric acid-reactive substances (TBARS) assay is a recognized method for determination of oxidized LDL, however this method is unable to distinguish between mm-LDL and oxLDL. In this study, seven specific monoclonal antibodies (mAbs) against human LDL were generated and selectively bound to the apolipoprotein B-100 (apoB-100) component of LDL. Oxidized LDL was produced by incubation of human LDL with 10 μM CuSO4 for various times. The TBARS assay revealed that the optimal incubation time to achieve maximal lipid oxidation was 9 h. Indirect ELISA using the newly generated mAbs was implemented to differentiate between mm-LDL and oxLDL and it was found that binding of the mAbs to oxLDL was significantly decreased after 48 h of incubation, reflecting the oxidative modification of apoB-100. Our results suggest that the optimal times for incubation of LDL with CuSO4 for generation of mm-LDL and oxLDL were 9 h and 48 h, respectively.

Assessment of oxidative stress in follicular fluid of infertile women undergoing IVF procedure

Oxidative stress (OS) plays an important role in biological processes of reproduction, and yet there is no accurate indicator to measure it. The objective of the study was to correlate the effect of ROS (reactive oxygen species) on embryo quality and pregnancy outcome. This was achieved by measuring levels of ROS present in granulosa cells and follicular fluid (FF) of women undergoing IVF (in vitro fertilization). ROS in FF is measured using thiobarbituric acid reactive substances assay kit (Abcam) and granulosa cells were measured with the help of flow cytometry. The results showed that high levels of FF malondialdehyde were found in nonpregnant women as compared to pregnant group and were found to be significant (P 0.05) but had an impact on the quality of embryos (P

EFFECT OF PASTEURIZATION ON THE ANTIOXIDANT AND OXIDANT PROPERTIES OF HUMAN MILK.

ABSTRACTObjective: To evaluate the effect of pasteurization on antioxidant and oxidant properties of human milk.Methods: 42 samples of milk before and after pasteurisation were used to evaluate the antioxidant activity by the ferric reducing capacity and by scavenging the 2,2’-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid radical. Lipid peroxidation was estimated by the concentration of malondialdehyde product using the thiobarbituric acid reactive substances assay and by the evaluation of advanced oxidation protein products.Results: No significant difference was observed in fresh human milk and after pasteurization in relation to antioxidant properties determined by the ferric reducing capacity (50.0±3.4% and 48.8±3.0%, respectively) and by scavenging the 2,2’-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid radical (28.9±1.5% and 31.2±1.3%, respectively). The results of malondialdehyde (62.6±4.1 and 64.3±3.6 µM/mg) and protein oxidation products (59.4±3.4 and 54.2±3.8 µM/L) of fresh and pasteurized milk, respectively, did not exhibited any significant difference.Conclusions: This data showed that human milk has an important antioxidant activity and that the pasteurizing process does not influence the antioxidant capacity, avoiding the peroxidation of breast milk lipids and the formation of advanced protein oxidation products.

Antioxidant properties and in vitro effects on amphistomes of certain medicinal plants of Assam

People living in remote areas of the world, especially ethnic groups, practice traditional medicine as the first choice of disease treatment. Tribal communities of the Bodoland region of Assam use traditional medicines against various diseases. The present study investigated the antioxidant activities of Cassia fistula, Lindernia crustacea, Rauvolfia tetraphylla, Ricinus communis, Sacciolepis myosuroides and Zingiber zerumbet, which are medicinal plants traditionally consumed as deworming agents and their effects against amphistomes. Antioxidant activity was measured using the phosphomolybdate method, ferric reducing power, 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid, and thiobarbituric acid reactive substances assays. Amphistomes was treated with different doses of plant extracts in vitro to study their anthelmintic activity. The extracts of C. fistula, R. communis, and Z. zerumbet showed high antioxidant property. The plant extracts elicited a dose-dependent anthelmintic activity against amphistomes. Among the plants, C. fistula and L. crustacea showed the most potent anthelmintic property, comparable to reference drug albendazole. The study observed a positive correlation between the anthelmintic and antioxidant properties of the plants (P=0.05 level). The present study documents that the extracts of C. fistula and L. crustacea could be a potential source of anthelmintic agents. However, further study needs to be carried out to explore the anthelmintic activity of the plants.

Effects of the methanol fraction of modified Seonghyangjeongki-san water extract on transient ischaemic brain injury in mice

Context Recently in Korean medicine, the antioxidant and anti-inflammatory activities of Seonghyangjeongki-san (SHJKS) were reported. However, studies on the specific mechanisms of action of SHJKS for the treatment of ischaemic stroke are still lacking. Objective This study investigates the mechanism of action of the water extract methanol fraction of modified SHJKS (SHJKSmex) on cerebral ischaemic injury. Materials and methods C57BL/6 male mice were orally administered SHJKSmex (30, 100, or 300 mg/kg) for 3 consecutive days (2 days, 1 day, and 1 h, respectively) before middle cerebral artery occlusion (MCAO). Twenty-four hours after MCAO, the infarct volumes were measured, brain edoema indices were calculated, and neurological deficit scores were determined. Inflammation-related substances in the ipsilateral hemisphere were determined by western blotting, dichlorofluorescin diacetate, thiobarbituric acid-reactive substances assay, and enzyme-linked immunosorbent assay. Results SHJKSmex pre-treatment at 300 mg/kg decreased infarct volume by 87% and mean brain water content by 90% of the MCAO control group. Moreover, SHJKSmex effectively suppressed the expression of inducible nitric oxide synthase, reactive oxygen species, interleukin 1, and caspases-8 and −9 and increased the B-cell lymphoma 2/Bcl-2-associated X protein ratio (Bcl-2/Bax) in ischaemic mouse brain. The hippocampal pyramidal cell densities were significantly increased in the 300 mg/kg SHJKSmex-administered group compared to the MCAO control group. Discussion and conclusions SHJKSmex protected the brain from ischaemic stroke in mice through its antioxidant, anti-inflammatory, and antiapoptotic activities. Our findings suggest that SHJKSmex is a promising therapeutic candidate for the development of a new formulation for ischaemia-induced brain damage.

Effect of Selected Wood Smoke on Physicochemical and Sensory Qualities of Tilapia (Oreochromis niloticus)

ABSTRACT Different preservation and processing techniques have been used to extend the shelf life of fish. Smoking is a technique that enhances the flavor, color, texture, and shelf life of fish. This study was conducted to identify specific smoking conditions for tilapia (Oreochromis niloticus), while comparing the physicochemical and sensory qualities of tilapia smoked using selected wood smokes. Tilapia fillets of the same thickness were obtained, and trials were conducted to identify the best brine concentration, temperature/time combination, and wood material. The fillets were immersed in brine containing 2.5, 5.0, 7.5, 10.0, and 12.5% (w/v) NaCl for 1 hour. Then, fillets were smoked with wood smoke at three different temperatures (50, 60, and 70°C) and three drying times (3, 4, and 5 hours) using a smoking oven. Based on the selected temperature/time combinations, tilapia were smoked using mahogany, cinnamon, or their combination (1:1). Final products were vacuum-packed and stored at 4°C for analysis. Quality changes in sensory attributes were tested by 30 untrained panelists. Microbial quality (Salmonella, Escherichia coli, and total plate count), thiobarbituric acid reactive substances assay, and color were determined during 21 days of chilled storage, and proximate analysis was conducted. Fish brined in 10% (w/v) NaCl and smoked at 60°C for 4 hours using mahogany: cinnamon at 1:1 had the best sensory qualities (p < .05). Microbial counts and lipid oxidation were within the permitted levels, while no Escherichia coli and Salmonella sp. were observed. During the chilled storage, an increase in lightness (40.85 ± 0.32 to 42.02 ± 1.22) was observed, whereas the redness (8.86 ± 0.69 to 6.84 ± 0.11) was decreased. In conclusion, immersing tilapia fillets in brine containing 10% (w/v) NaCl followed by smoking at 60°C for 4 hours using mahogany: cinnamon at 1:1 can be considered as the best conditions to produce smoked tilapia. However, further studies need to be done to compare the chemical changes that occurred due to smoking.

Deficiency of Mitochondrial Functions and Peroxidation of Frontoparietal Cortex Enhance Isoflurane Sensitivity in Aging Mice.

Background: Hypersensitivity to general anesthetics may predict poor postoperative outcomes, especially among the older subjects. Therefore, it is essential to elucidate the mechanism underlying hypersensitivity to volatile anesthetics in the aging population. Given the fact that isoflurane sensitivity increases with aging, we hypothesized that deficiencies of mitochondrial function and elevated oxidative levels in the frontoparietal cortex may contribute to the enhanced sensitivity to isoflurane in aging mice.Methods: Isoflurane sensitivity in aging mice was determined by the concentration of isoflurane that is required for loss of righting reflex (LORR). Mitochondrial bioenergetics of the frontoparietal cortex was measured using a Seahorse XFp analyzer. Protein oxidation and lipid oxidation in the frontoparietal cortex were assessed using the Oxyblot protein oxidation detection kit and thiobarbituric acid reactive substance (TBARS) assay, respectively. Contributions of mitochondrial complex II inhibition by malonate and peroxidation by ozone to isoflurane sensitivity were tested in vivo. Besides, effects of antioxidative therapy on mitochondrial function and isoflurane sensitivity in mice were also measured.Results: The mean concentration of isoflurane that is required for LORR in aging mice (14–16 months old) was 0.83% ± 0.13% (mean ± SD, n = 80). Then, the mice were divided into three groups as sensitive group (S group, mean − SD), medium group (M group), and resistant group (R group, mean + SD) based on individual concentrations of isoflurane required for LORR. Activities of mitochondrial complex II and complex IV in mice of the S group were significantly lower than those of the R group, while frontoparietal cortical malondialdehyde (MDA) levels were higher in the mice of S group. Both inhibition of mitochondrial complexes and peroxidation significantly decreased the concentration of isoflurane that is required for LORR in vivo. After treatment with idebenone, the levels of lipid oxidation were alleviated and mitochondrial function was restored in aging mice. The concentration of isoflurane that required for LORR was also elevated after idebenone treatment.Conclusions: Decreased mitochondrial functions and higher oxidative stress levels in the frontoparietal cortex may contribute to the hypersensitivity to isoflurane in aging mice.

Effect of ascorbic acid and hemin on experimental colon carcinogenesis in mice

Colon cancer is known as the third most widespread cancer in the world. The interaction of heme-iron and ascorbic acid (AA) in colon carcinogenesis is not evident. Hemin (ferric chloride heme) is an iron-containing porphyrin with chlorine that can be formed from a heme group. The purpose of this study was to investigate the protective effect of AA on the formation of pre-neoplastic lesions induced by azoxymethane (AOM)/dextran sodium sulfate (DSS) plus hemin in mice. Forty-five ICR male mice were divided into three experimental groups; AOM/ DSS treatment (control group), hemin (2 g hemin/kg of b.w.), hemin + AA (1.0% in drinking water). The mice had three s.c. injections (0–2nd weeks of the experiment) of AOM (10 mg/kg b.w.) weekly and 2% DSS as drinking water for the next one week and the animals fed on AIN-76A purified rodent diet for 6 weeks. The numbers of aberrant crypt foci (ACF) and aberrant crypts (ACs) in colonic mucosa were counted after methylene blue staining. Lipid peroxidation in feces was measured by the thiobarbituric acid-reactive substances (TBARS) assay. The numbers of ACF and ACs per colon significantly increased in Hemin group compared to the control group. However, the numbers of ACF and ACs per colon notably decreased in hemin + AA group compared to the control group or hemin group (p&lt;0.05). In feces, the TBARS value of hemin group was higher than the control group (p&lt;0.01). The TBARS value of hemin + AA group was slightly decreased compared to Hemin group. These results indicate that hemin can promote the experimental colon carcinogenesis in ICR mice. On the other hand, additional supplement of AA via drinking water has a protective effect against the colon carcinogenesis. The related mechanisms need to be illustrated by further studies in future.

Cytotoxicity and Genotoxicity of E-Cigarette Generated Aerosols Containing Diverse Flavoring Products and Nicotine in Oral Epithelial Cell Lines.

Electronic cigarettes are the most commonly used nicotine containing product among teenagers. The oral epithelium is the first site of exposure and our recent work revealed considerable diversity among e-liquids for composition and level of chemical constituents that impact nicotine deposition in a human oral-trachea cast and affect the formation of reactive carbonyls. Here, we evaluate the dose response for cytotoxicity and genotoxicity of e-cigarette-generated aerosols from 10 diverse flavored e-liquid products with and without nicotine compared with unflavored in 3 immortalized oral epithelial cell lines. Three e-liquids, Blue Pucker, Love Potion, and Jamestown caused ≥20% cell toxicity assessed by the neutral red uptake assay. Nine products induced significant levels of oxidative stress up to 2.4-fold quantified by the ROS-Glo assay in at least 1 cell line, with dose response seen for Love Potion with and without nicotine across all cell lines. Lipid peroxidation detected by the thiobarbituric acid reactive substances assay was less common among products; however, dose response increases up to 12-fold were seen for individual cell lines. Micronuclei formation indicative of genotoxicity was increased up to 5-fold for some products. Blue Pucker was the most genotoxic e-liquid, inducing micronuclei across all cell lines irrespective of nicotine status. A potency score derived from all assays identified Blue Pucker and Love Potion as the most hazardous e-liquids. These in vitro acute exposure studies provide new insight about the potential for some flavored vaping products to induce significant levels of oxidative stress and genotoxicity.

High HbA1c levels affect motility parameters and overexpress oxidative stress of human mature spermatozoa.

The aim of this study is to investigate, by a validated in vitro model, the effect of diabetic plasma on ejaculated human spermatozoa. Plasma of 51 male diabetic patients (mean age 62.28±9.28years) was selected according to their HbA1c level: low HBA1c ≤5% (31mmol/mol), moderate HBA1c 6%-8% (42-64mmol/mol) and high HBA1c ≥10% (86mmol/mol). The plasma was tested on eighteen normal semen samples by analysing gametes motility using a computer Sperm Class Analyzer® and their corresponding oxidative stress (OS) status using thiobarbituric acid-reactive substances assay. The results indicated that diabetic plasma affected all sperm motility parameters with high HbA1c showing the most important deleterious effects. Low gametes' straight-line velocity was observed in high HbA1c level, mainly after 20min of co-incubation (8.78±0.47µm/s). Also, the highest lipid peroxidation (nmoles MDA/108 SPZ) was observed in high HbA1c values (0.92±0.09), higher than those in spermatozoa treated with H2 O2 (0.85±0.04). Conclusively, a direct impact of diabetic plasma on spermatozoa is revealed with overexpression of OS as the underlying mechanism. These findings suggested that it is strongly recommended to control clinically the glycaemic level and OS in diabetic patients for the maintenance of male fertility.

Potential of Propolis Extract as a Natural Antioxidant and Antimicrobial in Gelatin Films Applied to Rainbow Trout (Oncorhynchus mykiss) Fillets.

Usage of edible films and coatings alone or incorporated with natural extracts are a new approach to preservation and packaging of food. In this study, therefore, the microbiological, chemical quality, and sensorial changes of rainbow trout fillets coated with gelatin films supplemented with propolis extract (PE) (2, 8, 16%), as a source of polyphenols, were determined during 15 days of refrigerated storage (4 ± 1 °C). According to peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) assays, lipid oxidation was delayed in the fillets coated with gelatin films incorporated with PE comparing with the control and gelatin-coated (without PE) fillets. The total volatile basic nitrogen (TVB-N) value of rainbow trout fillets showed an increase in all groups at the end of storage, observing the lowest values in the fillets coated with gelatin films prepared with 16% PE. Gelatin films enriched with PE had great inhibitory effects on the microbial growth in rainbow trout fillets. The addition of PE enhanced the effectiveness of gelatin films and delayed the lipid oxidation and sensory and microbial deterioration in trout fillets coated with these films. Thus, PE can be recommended to be used as a natural antioxidant and antimicrobial additive with gelatin films to maintain rainbow trout fillet quality.

Lipid oxidation in oil-in-water emulsions: Iron complexation by buffer ions and transfer on the interface as a possible mechanism

Lipid oxidation is the main hurdle for omega-3 fatty acid enrichment in food and beverages. Fat oxidation reduces the quality and safety of supplemented products. A tuna oil-in-water emulsion (20%v/v) was exposed to iron-induced oxidation. Emulsions with changing emulsifiers and buffers were analyzed under different storage conditions (argon purging, pH variation) using Conjugated Dienes and Thiobarbituric acid reactive substances assays. The results showed that free iron ions cannot interact with oxygen. However, buffers (Citrate and phosphate) chelate iron ions (Fe (II)). Depending on the pH value and the type of buffer-Fe (II) complex, its prooxidant activity and spatial distribution are influenced. The complex charge defines the interactions with the oil-water interface, i.e., positively charged interfaces repel positively charged complexes which keeps the prooxidant away. The mechanistic understanding of this work will help formulators and product developers to choose the right buffer and emulsifier combination for oxidation sensitive emulsions.

Effect of Occupational Exposure to Herbicides on Oxidative Stress in Sprayers.

BackgroundHerbicides such as glyphosate, paraquat, and 2,4-dichlorophenoxyacetic acid have been reported to cause adverse side effects through production of reactive oxygen species. However, there were no data representing the adverse effects of a mixture herbicide usage in farmers, especially the changes in oxidative marker and antioxidant defense. This study aimed to determine the urinary malondialdehyde (MDA) and glutathione (GSH) level in farmers using mixed herbicides.MethodsNinety-three farmers were recruited, and two spot urine samples (before and after work) were collected. The urinary MDA level was evaluated by thiobarbituric acid reactive substance assay, and the urinary GSH level was determined using the enzymatic recycling method.ResultsSixty-two percent of the participants were men, and 59% of the participants worked in a farm for 20–40 years. The common combinations of herbicide usage were glyphosate with 2,4-dichlorophenoxyacetic acid (36.5%). There was no significant difference between pre- and post-work urinary MDA and GSH levels among the 3 groups of herbicides. However, the urinary MDA levels in farmers using the combination of glyphosate and paraquat were significantly higher than those found in farmers using glyphosate alone. The associated factors with changes in MDA levels found that the exposure intensity index (B = 0.154), the cumulative exposure intensity index (B = 0.023), and wearing gloves while working (B = −2.347) were found to be significantly associated with MDA level.ConclusionThe results suggest that the combined use of glyphosate and paraquat caused a significant increase in urinary MDA levels. Moreover, intensity of exposure to herbicide and wearing gloves were associated with the level of MDA.

Bioactive compounds, phenolic profile, antioxidant capacity and effectiveness against lipid peroxidation of cell membranes of Mauritia flexuosa L. fruit extracts from three biomes in the Ecuadorian Amazon

The bioactive compounds, total antioxidant capacity and protective effect against lipid oxidative damage of red blood cell (RBC) membranes of Mauritia flexuosa L. extracts from three altitude levels (low, middle and high zones) were analyzed. The identification of the main polyphenols in the fruit was performed using High Performance Liquid Chromatography/Electrospray Ionization Tandem Mass Spectrometry analysis, while High-Performance Liquid Chromatography - Diode Array Detector was applied for the vitamin C and carotenoid analysis. The ability of the extracts (methanolic, free polyphenols and bound polyphenols) to protect RBC membranes against oxidative destruction was assessed utilizing the thiobarbituric acid reactive substance assay (TBARS) assay. Among the 14 phenolic compounds identified, quercetin glycosides were the most predominant ones. The fruit from the middle altitude zone showed higher vitamin C and lutein contents than those from the low and high areas, whilst higher values of β-Carotene were obtained in M. flexuosa L. from the low zone. The contents of flavonoids and total polyphenols were lower in fruit from the low zone, whilst the fruit from the middle zone had the highest values. Similar results were observed in the results of the antioxidant capacity assays. However, a significant difference was not found in the protective effect of the extracts from the three altitude zones against lipid peroxidation in RBC membranes.