Inhibit Lipid Oxidation Research Articles

Ginsenoside Rb1 inhibits ferroptosis to ameliorate hypoxic-ischemic brain damage in neonatal rats.

Hypoxic ischemic encephalopathy (HIE) is among the leading causes of neonatal mortality, and currently there is no effective treatment. Ginsenoside Rb1 (GsRb1) is one of the principal active components of ginseng, and has protective benefits against oxidative stress, inflammation, hypoxic injury, and so on. However, the role and underlying mechanism of GsRb1 on HIE are unclear. Here, we established the neonatal rat hypoxic-ischemic brain damage (HIBD) model in vivo and the PC12 cell oxygen-glucose deprivation (OGD) model in vitro to investigate the neuroprotective effects of GsRb1 on HIE, and illuminate the potential mechanism. Our results showed that GsRb1 and the ferroptosis inhibitor liproxstatin-1 (Lip-1) could significantly restore System Xc activity and antioxidant levels as well as inhibit lipid oxidation levels and inflammatory index levels of HIBD and OGD models. Taken together, GsRb1 might inhibit ferroptosis to exert neuroprotective effects on HIE through alleviating oxidative stress and inflammation, which will set the foundation for future research on ferroptosis by reducing hypoxic-ischemic brain injury and suggest that GsRb1 might be a promising therapeutic agent for HIE.

Sodium nitrite (NaNO2) regulating myoglobin-mediated lipid oxidation in washed bovine mince

ABSTRACT This study investigated the effect of NaNO2 on inhibiting myoglobin-mediated lipid oxidation in muscle using a washed bovine mince model. We measured various parameters, including TBARS and PV to determine lipid oxidation, non-heme iron release, protoporphyrin destruction, and nitrosylmyoglobin production. The results of the study showed that the addition of NaNO2 during myoglobin-mediated lipid oxidation significantly reduced the fading and lipid oxidation of washed muscle (p < 0.05). Additionally, the addition of NaNO2 reduced the release of non-heme iron and the degradation of protoporphyrin in myoglobin. Nitrosylmyoglobin was formed in the washed mince supplemented with NaNO2 and myoglobin. These findings suggest that NaNO2 can effectively inhibit the lipid oxidation process induced by myoglobin, which could be a crucial aspect of nitrite inhibition of lipid oxidation in cured meat products. Overall, the study provides evidence for the potential use of NaNO2 as a food preservative to prevent lipid oxidation in meat products.

A novel strategy for inhibiting AGEs in fried fish cakes: Grape seed extract surimi slurry coating

This study investigated the effect of different surimi slurry coatings (SS, SSBHT, and SSGSE) on the AGEs of fried fish cakes. Results showed that all surimi slurry coatings significantly reduced AGEs in fried fish cakes, with SSGSE addition being most effective (P < 0.05). The SSGSE group performed a better sensory acceptance, higher moisture content, and denser texture than the other groups. The fat content and TBARS value of fried cakes were reduced by approximately 31% and 29% respectively by the SSGSE coating. Correlation analysis showed a negative correlation of AGEs content with moisture content and a positive correlation with browning, fat content and TBARS value. Conclusively, SSGSE coating reduced the generation of Maillard reaction products by inhibiting lipid oxidation in the fried fish cake. Thus, it was considered that grape seed extract surimi slurry was a promising coating technique to inhibit the production of AGEs in fried fish cakes.

An edible coating utilizing Malva sylvestris seed polysaccharide mucilage and postbiotic from Saccharomyces cerevisiae var. boulardii for the preservation of lamb meat

Currently, microbial bioactive substances (postbiotics) are considered a promising tool for achieving customer demand for natural preservatives. This study aimed to investigate the effectiveness of an edible coating developed by Malva sylvestris seed polysaccharide mucilage (MSM) and postbiotics from Saccharomyces cerevisiae var. boulardii ATCC MYA-796 (PSB) for the preservation of lamb meat. PSB were synthesized, and a gas chromatograph connected to a mass spectrometer and a Fourier transform infrared spectrometer were used to determine their chemical components and main functional groups, respectively. The Folin-Ciocalteu and aluminium chloride techniques were utilized to assess the total flavonoid and phenolic levels of PSB. Following that, PSB has been incorporated into the coating mixture, which contains MSM, and its potential radical scavenging and antibacterial activities on lamb meat samples were determined after 10 days of 4 °C storage. PSB contains 2-Methyldecane, 2-Methylpiperidine, phenol, 2,4-bis (1,1-dimethyl ethyl), 5,10-Diethoxy-2,3,7,8- tetrahydro-1H,6H-dipyrrolo[1,2-a:1′,2′-d] pyrazine, and Ergotaman-3′,6′,18-trione, 12′-hydroxy-2′-methyl-5′-(phenylmethyl)-, (5’alpha) as well as various organic acids with significant radical scavenging activity (84.60 ± 0.62 %) and antibacterial action toward Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, Staphylococcus aureus, and Listeria innocua as foodborne pathogens. The edible PSB-MSM coating effectively reduced microbial growth and increased meat shelf life (> 10 days). When PSB solutions were added to the edible coating, the moisture content, pH value, and hardness of the samples were also more successfully maintained (P < 0.05). The PSB-MSM coating inhibited lipid oxidation in meat samples considerably and diminished the formation of primary as well as secondary oxidation intermediates (P < 0.05). Additionally, when MSM + 10 % PSB edible coating was utilized, the sensory properties of the samples were maintained more well during preservation. As a significance, the use of edible coatings based on PSB and MSM is efficient in decreasing microbiological and chemical degradation in lamb meat during preservation.

Influence of aerial and vacuum packaging on the quality and shelf life of beef treated with extra virgin olive oil

The aim of this study was to evaluate the effects of olive oil as a natural preservative and aerial and vacuum packaging on the quality and shelf life of raw beef. Meat samples were divided into four treatments i.e. T0= with 1% olive oil and aerial packaged, T1= without olive oil and aerial packaged, T2 = with 1% olive oil and vacuum packaged and T3 = without olive oil and vacuum packaged. All samples were kept at refrigerated temperature. Days of interval were 0, 5, 10 and 15. The samples were tested for sensory properties (color, flavor, tenderness, juiciness and overall acceptability), physicochemical characteristics (water holding capacity, cooking loss, pH); biochemical properties (TBARS), and microbiological counts (TVC, TCC and TYMC). During the whole storage process, the sensory and instrumental color value were considerably higher (P&lt;0.05) in T0 and T2 treatments. WHC in treatment T2 was higher, CL was lower in T0 treatment and pH in treatment of T0, T1 were considerably higher (P&lt;0.05) than in the T2 and T3 group. The values of TBARS, viable count, coliform count, and yeast-mold count were significantly lower in T0 and T2 group. Based on the findings of this study, it is possible to conclude that olive oil treated beef in aerial and vacuum packaging storage technique can be used in the future for meat preservation, providing antioxidant and antimicrobial agents as a value addition by inhibiting lipid oxidation and extending the shelf life of beef.

Composition, in vitro antioxidant and angiotensin-converting enzyme inhibitory effects of lipids isolated from fifteen species of seaweeds

In this study, the lipid profile, in vitro antioxidant and angiotensin-converting enzyme (ACE) inhibitory effect of lipid extracts from 15 species of seaweed were evaluated. The lipid content varied from 0.7 ± 0.1 to 3.9 ± 0.3 g/100g dry weight. Brown seaweeds showed high levels of neutral lipids, whereas red seaweeds contained more polar lipids. Most of the sterols were in free form than the esterified form. The levels of polyunsaturated fatty acids (PUFAs) ranged from 8.1 ± 0.1% to 54.6 ± 6.9%, with α-linolenic acid (C18:3n-3) and eicosapentaenoic acid (C20:5n-3) being the primary ω-3 PUFAs, while arachidonic acid (C20:4n-6) was the main ω-6 PUFA. Lipid extracts from Polysiphonia platycarpa, Chondria cornuta and Sargassum boveanum showed the highest radical scavenging activity, whereas Padina gymnospora and Ulva lactuca had the highest iron chelating activity. Lipid extracts from B. pulmosa and P. gymnospora showed the highest protection against lipid oxidation and angiotensin-converting enzyme inhibition. These macroalgal lipids can be used as a potential source of bioactive compounds for food and pharma.

LDPE and PLA Active Food Packaging Incorporated with Lemon by-Products Extract: Preparation, Characterization and Effectiveness to Delay Lipid Oxidation in Almonds and Beef Meat.

Low-density polyethylene-based packaging with 4% lemon extract (LDPE/4LE) and two polylactic-based (PLA) packaging materials with 4% and 6% lemon extract (PLA/PEG/4LE and PLA/6LE) were produced. O2 and water permeability tests were performed, the total and individual phenolic compounds content were measured, and the films' antioxidant activities were determined. The films' ability to delay lipid oxidation was tested in two model foods: almonds, packaged with LDPE/4LE, PLA/4LE and PLA/6LE for a maximum period of 60 days at 40 °C (accelerated assay); and beef meat, packaged with the PLA/6LE for a maximum period of 11 days at 4 °C. The LE improved the WVP in all of the active films by 33%, 20% and 60% for the LDPE/4LE, PLA/4LE and PLA/6LE films, respectively. At the end of 10 days, the migration of phenolic compounds through the PLA films was measured to be 142.27 and 114.9 μg/dm2 for the PLA/4LE and PLA/6LE films, respectively, and was significantly higher than phenolic compounds migration measured for the LDPE/4LE (15.97 μg/dm2). Naringenin, apigenin, ferulic acid, eriocitrin, hesperidin and 4-hydroxybenzoic acid were the main identified compounds in the PLA, but only 4-hydroxybenzoic acid, naringenin and p-coumaric acid were identified in the LDPE films. Regarding the films' ability to delay lipid oxidation, LDPE/4LE presented the best results, showing a capacity to delay lipid oxidation in almonds for 30 days. When applied to raw beef meat, the PLA/6LE packaging was able to significantly inhibit lipid oxidation for 6 days, and successfully inhibited total microorganisms' growth until the 8th day of storage.

Antioxidant Activities of Essential Oils and Their Major Components in Scavenging Free Radicals, Inhibiting Lipid Oxidation and Reducing Cellular Oxidative Stress.

Antioxidant activities of five essential oils (cinnamon, thyme, clove, lavender and peppermint oils) and their major components (eugenol, thymol, linalool, and menthol) were evaluated on scavenging DPPH (2,2-diphenyl-1 picrylhydrazyl) free radicals, inhibiting polyunsaturated fatty acid oxidation in fish oil emulsion (FOE), and reducing oxidative stress in human red blood cells (RBC). The essential oils from cinnamon, thyme, clove and their main components, eugenol and thymol, exhibited the highest antioxidant activity in the FOE and RBC systems. It was found that the antioxidant activity of essential oils was positively correlated to the content of eugenol and thymol, while lavender and peppermint oils and their main components, linalool and menthol, had very low antioxidant activity. Compared with scavenging DPPH free radical activity, the antioxidant activity in FOE and RBC systems could better reflect the actual antioxidant potential of essential oil in preventing lipid oxidation and reducing oxidative stress in biological system.

Nanoparticles of metals and their compounds in films and coatings: A review

Nanotechnology is important in food packaging because it increases shelf life, enhances food safety, and improves sensory characteristics and nutrient availability. We aimed to review scientific publications on the synthesis of nanoparticles, as well as their properties and applications in the food industry.&#x0D; Research and review articles published from 2020 to 2022 were obtained from the database using the keywords “nanoparticles”, “film”, and “food”. They were on the synthesis of metal and metal oxide nanoparticles and their uses in food films and coatings. &#x0D; We reviewed methods for synthesizing inorganic nanoparticles from metals and their compounds (silver, zinc, iron, etc.), as well as described their antimicrobial action against foodborne pathogens. By incorporating nanoparticles into films, we can create new materials with strong antimicrobial properties in vitro. Nanoparticles can be used to develop both polymer and biopolymer films, as well as their mixtures. Composite coatings can work synergistically with metal nanoparticles to create multifunctional food packaging systems that can act as compatibilizers. Particular attention was paid to metal nanoparticles in food coatings. We found that nanoparticles reduce the rate of microbial spoilage and inhibit lipid oxidation, thereby increasing the shelf life of raw materials and ready-to-eat foods. The safety of using nanoparticles in food coatings is an important concern. Therefore, we also considered the migration of nanoparticles from the coating into the food product.&#x0D; Incorporating nanoparticles into polymer and biopolymer films can create new materials with antimicrobial properties against foodborne pathogens. Such composite films can effectively extend the shelf life of food products. However, the undesirable migration of metal ions into the food product may limit the use of such films.

Efficiency of δ-Tocopherol in Inhibiting Lipid Oxidation in Emulsions: Effects of Surfactant Charge and of Surfactant Concentration.

Charged interfaces may play an important role in the fate of chemical reactions. Alterations in, for instance, the interfacial acidity of emulsions induced by the charge of the surfactant head group and associated counterions may change the ionization status of antioxidants, modifying their effective concentrations. The chemical reactivity between interfacial reactants and charged species of opposite charge (protons, metallic ions, etc.) is usually interpreted in terms of pseudophase ion-exchange models, treating the distribution of charged species in terms of partitioning and ion exchange. Here, we focus on analyzing the effects of charged interfaces on the oxidative stability of soybean oil-in-water (o/w) emulsions prepared with anionic (sodium dodecyl sulfate, SDS), cationic (cetyltrimethylammonium bromide, CTAB) and neutral (Tween 20) surfactants, and some of their mixtures, in the presence and absence of δ-tocopherol (δ-TOC). We have also determined the effective concentrations of δ-TOC in the oil, interfacial and aqueous regions of the intact emulsions. In the absence of δ-TOC, the relative oxidative stability order was CTAB < TW20 ~ TW20/CTAB < SDS. Surprisingly, upon the addition of δ-TOC, the relative order was SDS ≈ TW20 << TW20/CTAB < CTAB. These apparently surprising results can be rationalized in terms of the nice correlation that exists between the relative oxidative stability and the effective interfacial concentrations of δ-TOC in the various emulsions. The results emphasize the importance of considering the effective interfacial concentrations of antioxidants in interpreting their relative efficiency in emulsions.

Preparation of gelatin/carboxymethyl cellulose/guar gum edible films enriched with methanolic extracts from shallot wastes and its application in the microbiological control of raw beef

In this study, agricultural wastes from red onions or shallots were utilized to incorporate into edible film formulation from gelatin/carboxymethyl cellulose/guar gum for the preservation of fresh beef tenderloin. Shallot tunic extract (STE) was rich in phenolics (2613.54 ± 28.96 mg gallic acid equivalent/L) and anthocyanins (69.72 ± 0.72 mg cyanidin-3-glucoside/L) with high antioxidant and antimicrobial activities against eleven pathogenic microorganisms (Gram-positive bacteria, Gram-negative bacteria and fungi), especially Citrobacter freundii, Proteus mirabilis, and Listeria monocytogenes. According to the physical characterization (SEM, XRD, FT-IR), the addition of STE into film formulation led to a more identical microstructure, lower intensity peak at 2θ of 20°, and increase in the vibration of NCO group. Regarding the microbiological quality, total plate counts of beef coated with STE-containing edible films were controlled equivalent to the uncoated beef during storage. It is noticeable that E. coli, Coliforms and Staphylococcus aureus were effectively inhibited up to seven days by coating with STE-containing films, as illustrated by their significant lower counts compared to control samples. The lipid oxidation products were maintained at levels similar to those found in the original beef (0.17–0.27 mg malondialdehyde/kg of meat) owing to the STE-enriched films' ability to inhibit lipid oxidation.

Effect of Black Cumin Cake Extract, Octyl Caffeate, and Active Packaging on Antioxidant Properties of Egg-Free Mayonnaise during Storage

The egg-less mayonnaise (CM) based on aquafaba and refined rapeseed oil was prepared and enriched with black cumin cake extract (BCCE) at two concentrations of 0.1% (BCCM0.1%) and 3% (BCCM3%) and 0.1% of octyl caffeate (OCM). The obtained mayonnaises were placed in glass jars without and with active film incorporating BCCE at the jar bottom (AFM). The influence of antioxidants on oxidative stability and antioxidant capacity (AC) of the prepared mayonnaises was estimated by the shelf-life test. Peroxide value (PV), anisidine value (AnV), total oxidation (TOTOX) value, acid value (AV), and amounts of conjugated dienes (CD) and conjugated trienes (CT) were used to assess the extent of mayonnaise deterioration during storage of up to 4 weeks in a refrigerator. The synthesized octyl caffeate (OC) and natural antioxidants from BCCE added to mayonnaises directly and released from active film enhanced the AC of the studied mayonnaise samples determined using the QUick, Easy, New, CHEap, and Reproducible-2,2-diphenyl-1-picrylhydrazyl (QUENCHER-DPPH), and QUENCHER-2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (QUENCHER-ABTS) methods. All enriched mayonnaises had higher antioxidant potential than the AC of the control sample without antioxidants (CM) and commercial plant-based mayonnaise (CPBM). Therefore, the proposed antioxidants and active film can be used in the food industry to suppress lipid oxidation.

GPX4: The hub of lipid oxidation, ferroptosis, disease and treatment.

Glutathione peroxidase 4 (GPx4) moonlights as structural protein and antioxidase that powerfully inhibits lipid oxidation. In the past years, it is considered as a key regulator of ferroptosis, which takes role in the lipid and amine acid metabolism and influences the cell aging, oncogenesis, and cell death. More and more evidences show that targeting GPX4-induced ferroptosis is a promising strategy for disease therapy, especially cancer treatment. In view of these, we generalize the function of GPX4 and regulatory mechanism between GPX4 and ferroptosis, discuss its roles in the disease pathology, and focus on the recent advances of disease therapeutic potential.

Biological Evaluation and Computational Studies of Methoxy-flavones from Newly Isolated Radioresistant Micromonospora aurantiaca Strain TMC-15.

This study aims to determine UV-B resistance and to investigate computational analysis and antioxidant potential of methoxy-flavones of Micromonospora aurantiaca TMC-15 isolated from Thal Desert, Pakistan. The cellular extract was purified through solid-phase extraction and UV-Vis spectrum analysis indicated absorption peaks at λmax 250nm, 343nm, and 380nm that revealed the presence of methoxy-flavones named eupatilin and 5-hydroxyauranetin. The flavones were evaluated for their antioxidant as well as protein and lipid peroxidation inhibition potential using di(phenyl)-(2,4,6-trinitrophenyl) iminoazanium (DPPH), 2,4-dinitrophenyl hydrazine (DNPH), and thiobarbituric acid reactive substances (TBARS) assays, respectively. The methoxy-flavones were further studied for their docking affinity and interaction dynamics to determine their structural and energetic properties at the atomic level. The antioxidant potential, protein, and lipid oxidation inhibition and DNA damage preventive abilities were correlated as predicted by computational analysis. The eupatilin and 5-hydroxyauranetin binding potential to their targeted proteins 1N8Q and 1OG5 is - 4.1 and - 7.5kcal/mol, respectively. Moreover, the eupatiline and 5-hydroxyauranetin complexes illustrate van der Waals contacts and strong hydrogen bonds to their respective enzymes target. Both in vitro studies and computational analysis results revealed that methoxy-flavones of Micromonospora aurantiaca TMC-15 can be used against radiation-mediated oxidative damages due to its kosmotrophic nature. The demonstration of good antioxidant activities not only protect DNA but also protein and lipid oxidation and therefore could be a good candidate in radioprotective drugs and as sunscreen due to its kosmotropic nature.

Acylated pectin/gelatin-based films incorporated with alkylated starch crystals: Characterization, antioxidant and antibacterial activities, and coating preservation effects on golden pomfret

Pectin and starch crystals were modified by ethyl gallate and octadecyl-trimethoxysilane, respectively, followed by using acylated pectin (AP) and alkylated starch crystals (ASCs) as bioactive reagents and hydrophobic enhancers to improve the physiochemical properties of gelatin-based films and evaluate their coating preservation effects on golden pomfret. The properties of AP and ASC were investigated by Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–vis), proton-nuclear magnetic resonance (1H NMR) and X-ray diffraction (XRD). The ethyl-gallate-modified pectin/gelatin (AP/G) containing 3 % ASC (AP/G/ASC-3 %) was shown to have the maximum tensile strength and Young's modulus of all the tested composite films. The AP/G containing 10 % ASC exhibited a water contact angle higher than 94°, coupled with a significant improvement in UV-shielding efficiency. FTIR and SEM analysis of the AP/G/ASC-3 % film indicated that the molecular interactions in the composite film components were noncovalent linkages, including hydrogen bonds, hydrophobic interactions, and electrostatic interactions, contributing to homogeneous and smooth microstructures. Additionally, the solutions of AP/G and AP/G/ASC composite films presented obvious antioxidant and antibacterial activities against Escherichia coli and Staphylococcus aureus. Furthermore, the AP/G and AP/G/ASC active coatings could effectively inhibit lipid oxidation and improve the textural acceptability of golden pomfret (Trachinotus blochii) fillets during 4 °C storage.

The Inhibitory Effects of Hydroxytyrosol, α-Tocopherol and Ascorbyl Palmitate on Lipid Peroxidation in Deep-Fat Fried Seafood.

This study aimed to investigate the inhibitory effects of hydroxytyrosol, α-tocopherol and ascorbyl palmitate on lipid peroxidation in squid, hoki and prawn during deep-fat frying and refrigerated storage. Fatty acid analysis using gas chromatography (GC) showed that the seafood had a high omega-3 polyunsaturated fatty acid (n-3 PUFAs) content, including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The total content of n-3 fatty acids in their lipids was 46% (squid), 36% (hoki) and 33% (prawn), although they all had low lipid contents. The oxidation stability test results showed that deep-fat frying significantly increased the peroxide value (POV), p-anisidine value (p-AV) and the value of thiobarbituric acid reactive substances (TBARS) in squid, hoki and prawn lipids. Meanwhile, antioxidants delayed the lipid oxidation in fried seafood and sunflower oil (SFO) used for frying, albeit in different ways. The least effective of all the antioxidants was α-tocopherol, as the POV, p-AV and TBARS values obtained with this antioxidant were significantly higher. Ascorbyl palmitate was better than α-tocopherol but was not as effective as hydroxytyrosol in suppressing lipid oxidation in the frying medium (SFO) and in the seafood. However, unlike the ascorbyl palmitate-treated oil, hydroxytyrosol-treated oil could not be used for multiple deep-fat frying of seafood. Hydroxytyrosol appeared to be absorbed in the seafood during multiple frying, thus leaving a low concentration in the SFO and making it susceptible to oxidation.

Antioxidant activity and health effects from Malpighia emarginata fruit – a systematic review

Acerola (Malpighia emarginata) is considered a superfruit due to high vitamin C content and the presence of phenolics that confer antioxidant potential. Increasing of chronic disorders and results of oxidative stress-related diseases has encouraged the search of new pharmacological strategies to face them. The present review discusses the available knowledge on health effects of Malpighia emarginata, including both in vivo and in vitro studies. Records in 1945–2022 were extracted from Web of Science and Scopus databases to get the bibliometric index of the published articles. In spite of bibliometric analysis advantages to knowing about the trends in a subject, this research requires methods to support the investigation process through the selection of a relevant bibliographic portfolio. This study also applied the Methodi Ordinatio which provides an approach to rank 29 relevant publications. Fifty-one research articles were reviewed. Much knowledge comes from in vitro explorations, such as chemical assays evaluating radical scavenging properties, glycemic and lipid oxidation inhibition, and reducing capacity of acerola fruit; similarly, research on cellular substrates and animal models generally measures antioxidant enzymes levels and other antioxidant markers, such as α-glycosidase and advanced glycation end products. Reviewed data suggest that some acerola fruit compounds are deserving of further investigation and more useful understanding of their antioxidant and neuroprotective potentials.

Epicatechin Inhibited Lipid Oxidation and Protein Lipoxidation in a Fish Oil-Fortified Dairy Mimicking System

In this study, a typical tea polyphenol epicatechin (EC) was investigated for its impact on the oxidative stability of whey protein isolate (WPI) in a fish oil-fortified emulsion. The oil-in-water emulsion system consisted of fish oil (1%, w/w), WPI (6 mg/mL), and EC (0.1, 1, and 2 mM), and the oxidation reaction was catalyzed by Fenton's reagent at 25 °C for 24 h. The results showed EC exhibited a dose-dependent activity in the reduction of lipid oxidation (TBARS) and protein carbonylation. A Western blot analysis demonstrated that protein lipoxidation was inhibited by EC via interrupting the covalent binding of lipid secondary oxidation products, MDA, onto proteins. In addition, protein lipoxidation induced a loss of tryptophan fluorescence, and protein hydrolysis was partially recovered by EC. The findings of this study provide an in-depth understanding of the performance of phenolic antioxidants in relieving lipid oxidation and subsequent protein lipoxidation in oil-containing dairy products.

Neuroprotection of NAD+ and NBP against ischemia/reperfusion brain injury is associated with restoration of sirtuin-regulated metabolic homeostasis.

Background: Ischemic stroke seriously threatens human health because of high rates of morbidity, mortality and disability. This study compared the effects of nicotinamide adenine dinucleotide (NAD+) and butylphthalide (NBP) on in vitro and in vivo ischemic stroke models. Methods: Transient middle cerebral artery occlusion/reperfusion (t-MCAO/R) model was established in mice, and the cultured primary cortical neurons were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). Cerebral infarct volume, neurobehavioral indices, antioxidant activity, ATP level and lactic acid content were determined. The neuroprotective effects of NAD+ or NBP were compared using sirtuin inhibitor niacinamide (NAM). Results: Intraperitoneal injection of NBP within 4h or intravenous injection of NAD+ within 1h after t-MCAO/R significantly reduced the volume of infarcts, cerebral edema, and neurological deficits. Administration of NAD+ and NBP immediately after t-MCAO/R in mice showed similar neuroprotection against acute and long-term ischemic injury. Both NAD+ and NBP significantly inhibited the accumulation of MDA and H2O2 and reduced oxidative stress. NAD+ was superior to NBP in inhibiting lipid oxidation and DNA damage. Furthermore, although both NAD+ and NBP improved the morphology of mitochondrial damage induced by ischemia/reperfusion, NAD+ more effectively reversed the decrease of ATP and increase of lactic acid after ischemia/reperfusion compared with NBP. NAD+ but not NBP treatment significantly upregulated SIRT3 in the brain, but the sirtuin inhibitor NAM could abolish the protective effect of NAD+ and NBP by inhibiting SIRT1 or SIRT3. Conclusions: These results confirmed the protective effects of NAD+ and NBP on cerebral ischemic injury. NBP and NAD+ showed similar antioxidant effects, while NAD+ had better ability in restoring energy metabolism, possibly through upregulating the activity of SIRT1 and SIRT3. The protection provided by NBP against cerebral ischemia/reperfusion may be achieved through SIRT1.

The Inhibitory Effect of Gallic Acid Alkyl Esters on Lipid Oxidation of Intactly Soaked Oyster Meats and Oyster Meat Homogenates during Refrigerated Storage

AbstractIn this study, the antioxidant effects of gallic acid (GA) and its alkyl esters including methyl gallate (MG), butyl gallate (BG), octyl gallate (OG), and lauryl gallate (LG) in whole oyster meats and oyster meat homogenates during cold storage are investigated. The oxidation degree of lipid is measured by peroxide value (POV), thiobarbituric acid active substances (TBARS), and polyunsaturated fatty acid (PUFA) percentage. The results show that the lipid oxidation in the two types of samples is inhibited by GA alkyl esters, and the antioxidant effects first increase and then decrease along with the extension of the chain length, among the esters, BG and OG are relatively more effective. Therefore, it is speculated that the antioxidant capacity of GA alkyl esters may be influenced by hydrophobicity and follows a “cut‐off effect” in whole oyster meats and oyster meat homogenates.Practical application: Seafood is easily oxidized even under cold storage because it contains more PUFA. Antioxidants are widely used to inhibit lipid oxidation. In this study, the antioxidant capacity of GA alkyl esters in whole oyster meats and oyster meat homogenates is investigated, which improves the selection of suitable antioxidants to strengthen the oxidation stability of oyster samples for cold storage.