Mechanisms of Oxidative Processes in Meat and Toxicity Induced by Postprandial Degradation Products: A Review

Structural Properties of Globulin: A Critical Parameter for Sunflower Meal as Wood Panel Adhesives

Alternative biobased adhesive formulations are currently being investigated to replace urea-formaldehyde (UF) as wood panel adhesives. In this regard, oilseed meals are valuable alternatives, as it is anticipated that the sticky potential of these meals is linked to their protein content. This work focuses on the protein parameters (primary and/or secondary structures) that could impact the adhesiveness of sunflower meals. The proteins contained in these meals were first separated from the other components and identified using electrophoresis. Oilseed meals contain several families of proteins: globulins, albumins, prolamins, and oleosins. Sunflower meal is mainly composed of globulin (53%) and albumin (45%). The protein structures have then been either oxidized with H2O2 (in the presence or not of NaOH) or physically treated by microwave (MW). The oxidation treatment cleaves the protein backbone and creates smaller peptides, while the MW process converts α-helices into random coils. The adhesive potential of these treated proteins was evaluated by using shear tests onto wood panels. The results demonstrate that the primary and secondary structures of globulins are key parameters toward the sunflower protein meal adhesivity.

Dietary supplementation with quercetin: an ideal approach for improving meat quality and oxidative stability of broiler chickens

This study aimed to improve the eating quality of yellow-feathered broiler chicks by feeding them corn-soybean meal diets supplemented with 250, 500, and 1,000 mg/kg quercetin. we examined the impact of varying doses of dietary quercetin on the sensory quality of chicken breast meat as well as on the antioxidant enzymes, antioxidant-related signaling molecules, structure and thermal stability of myofibrillar protein (MPs), and microstructure of myogenic fibers in the meat during 24 h of postslaughter aging. Additionally, we investigated the potential correlations among antioxidant capacity, MP structure, and meat quality parameters. The results indicated that dietary supplementations with 500 and 1,000 mg/kg quercetin improved the physicochemical properties and eating quality of yellow-feathered broiler chicken breast meat during 12 to 24 h postslaughter. Additionally, quercetin improved the postslaughter oxidative stress status and reduced protein and lipid oxidation levels. It also increased hydrogen bonding interactions and α-helix content during 6 to 12 h postslaughter and decreased β-sheet content during 12 to 24 h postslaughter in chicken breast MP. This resulted in improved postslaughter MP structure and thermal stability. The correlation results indicated that the enhancement of antioxidant capacity and MP structure enhanced the physicochemical and edible qualities of yellow-feathered broiler chicken breast meat. In conclusion, the current findings suggest that dietary supplementation with quercetin is an ideal approach for improving the eating quality of chicken meat, thereby broadening our understanding of theoretical and technological applications for improving the quality of chicken.

Critical review and recent advances of emerging real-time and non-destructive strategies for meat spoilage monitoring

Monitoring and evaluating food quality, especially meat quality, has received a growing interest to ensure human health and decrease waste of raw materials. Standard analytical approaches used for meat spoilage assessment suffer from time consumption, being labor-intensive, operation complexity, and destructiveness. To overcome shortfalls of these traditional methods and monitor spoilage microorganisms or related metabolites of meat products across the supply chain, emerging analysis devices/systems with higher sensitivity, better portability, on-line/in-line, non-destructive and cost-effective property are urgently needed. Herein, we first overview the basic concepts, causes, and critical monitoring indicators associated with meat spoilage. Then, the conventional detection methods for meat spoilage are outlined objectively in their strengths and weaknesses. In addition, we place the focus on the recent research advances of emerging non-destructive devices and systems for assessing meat spoilage. These novel strategies demonstrate their powerful potential in the real-time evaluation of meat spoilage.

Research progress of chilled meat freshness detection based on nanozyme sensing systems

It is important to develop rapid, accurate, and portable technologies for detecting the freshness of chilled meat to meet the current demands of meat industry. This report introduces freshness indicators for monitoring the freshness changes of chilled meat, and systematically analyzes the current status of existing detection technologies which focus on the feasibility of using nanozyme for meat freshness sensing detection. Furthermore, it examines the limitations and foresees the future development trends of utilizing current nanozyme sensing systems in evaluating chilled meat freshness. Harmful chemicals are produced by food spoilage degradation, including biogenic amines, volatile amines, hydrogen sulfide, and xanthine, which have become new freshness indicators to evaluate the freshness of chilled meat. The recognition mechanisms are clarified based on the special chemical reaction with nanozyme or directly inducting the enzyme-like catalytic activity of nanozyme.

Lc-ms-based lipidomics analyses revealed changes in lipid profiles in Asian sea bass (Lates calcarifer) with dielectric barrier discharge (DBD) atmospheric plasma treatment

A comprehensive LC-MS-based lipidomics analysis of Asian sea bass (Lates calcarifer) muscle after dielectric barrier discharge (DBD) atmospheric plasma treatment was performed. Through the analysis, 1500 lipid species were detected, phosphatidylcholine (PC, 27.80%) was the most abundant lipid, followed by triglyceride (TG, 20.50%) and phosphatidylethanolamine (PE, 17.10%). Among them, 125 lipid species were detected and identified as differentially abundant lipids in Asian sea bass (ASB). PCA and OPLS-DA showed that ASB lipids changed significantly after DBD treatment. Moreover, glycerophospholipid metabolism was key metabolic pathways, as PC, PE, and lysophosphatidylcholine (LPC) were key lipid metabolites. The findings concerning fatty acids revealed that the saturated fatty acids (SFA) content of ASB after DBD treatment increased by 8.54%, while the content of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) decreased by 13.77% and 9.16%, respectively. Our study establishes a foundation for the lipid oxidation mechanism of ASB following DBD treatment.

Oregano essential oil encapsulated in zein-pectin-chitosan nanoparticles to improve the storage quality of Harbin red sausage

In this study, the effect of oregano essential oil loaded in zein-pectin-chitosan (Zein-PC-CS-OEO) nanoparticles on the quality of Harbin red sausage during storage was examined. Zein-PC-CS-OEO nanoparticles exhibit the better encapsulation efficiency, antioxidant and antibacterial properties than these of other prepared nanoparticles, which were subsequently incorporated into Harbin red sausage with different concentrations. The physicochemical properties, bacterial community structure, and flavor characteristics of the Harbin red sausage were determined. Both thiobarbituric acid values and the growth of dominant spoilage bacteria in Harbin red sausage are inhibited by Zein-PC-CS-OEO nanoparticles, while the total aerobic bacteria count is reduced. These results indicate that the storage quality of Harbin red sausage is improved by Zein-PC-CS-OEO nanoparticles. It is worth noting that the shelf life of Harbin red sausage supplemented with 0.1 % Zein-PC-CS-OEO nanoparticles is extended to 9 d, and the flavor characteristics of which are better maintained. This study provides a new approach to extend the application of essential oil and improve the storage quality of Harbin red sausage.

Cassia Seed Gum Films Incorporated with Partridge Tea Extract as an Edible Antioxidant Food Packaging Film for Preservation of Chicken Jerky

The use of edible packaging films to delay food spoilage has attracted widespread attention. In this study, partridge tea extract (PTE) was added to cassia gum (CG) to prepare CG/PTE films. The microstructure, optical, mechanical, barrier, and antioxidant properties of CG/PTE films were investigated, and the effect of PTE on CG films was shown. The films had high transparency and smooth surface structure. Additionally, PTE significantly improved the elongation at break and antioxidant activity of films. At 2.5% of PTE, the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging rate of the film was 46.88% after diluting 50 times, indicating excellent antioxidant property, which could be applied to food preservation. After 9 days of storage, the thiobarbituric acid reactive substances values (TBARS) of chicken jerk packaged with films containing 0% and 2.5% PTE increased from 0.12% to 1.04% and 0.11% to 0.40%, respectively. This study suggests that CG/PTE films can be used to preserve cooked meat.

Lipid Peroxidation in Muscle Foods: Impact on Quality, Safety and Human Health

The issue of lipid changes in muscle foods under the action of atmospheric oxygen has captured the attention of researchers for over a century. Lipid oxidative processes initiate during the slaughtering of animals and persist throughout subsequent technological processing and storage of the finished product. The oxidation of lipids in muscle foods is a phenomenon extensively deliberated in the scientific community, acknowledged as one of the pivotal factors affecting their quality, safety, and human health. This review delves into the nature of lipid oxidation in muscle foods, highlighting mechanisms of free radical initiation and the propagation of oxidative processes. Special attention is given to the natural antioxidant protective system and dietary factors influencing the stability of muscle lipids. The review traces mechanisms inhibiting oxidative processes, exploring how changes in lipid oxidative substrates, prooxidant activity, and the antioxidant protective system play a role. A critical review of the oxidative stability and safety of meat products is provided. The impact of oxidative processes on the quality of muscle foods, including flavour, aroma, taste, colour, and texture, is scrutinised. Additionally, the review monitors the effect of oxidised muscle foods on human health, particularly in relation to the autooxidation of cholesterol. Associations with coronary cardiovascular disease, brain stroke, and carcinogenesis linked to oxidative stress, and various infections are discussed. Further studies are also needed to formulate appropriate technological solutions to reduce the risk of chemical hazards caused by the initiation and development of lipid peroxidation processes in muscle foods.

Antioxidant activity of an Mg(II) compound containing ferulic acid as a chelator: potential application for active packaging and riboflavin stabilisation

Foods rich in riboflavin (Rf) are susceptible to degradation due to oxidative processes with the formation of radicals. Herein, we describe the features and stability of an Mg(II) complex containing ferulic acid (fer) and 1,10-phenanthroline (phen) as chelators: henceforth called Mg(phen)(fer). The electrochemical behavior of Mg(phen)(fer) is pH dependent and results from the stabilisation of the corresponding phenoxyl radical via complexation with Mg(II). This stabilisation enhances the antioxidant activity of Mg(phen)(fer) with respect to free fer and commercial antioxidants. Mg(phen)(fer) scavenges and neutralizes DPPH˙ (IC50 = 15.6 μmol L-1), ABTS˙+ (IC50 = 5.65 μmol L-1), peroxyl radical (IC50 = 5.64 μg L-1) and 1O2 (IC50 = 0.7 μg m-1). Mg(phen)(fer) effectively protects riboflavin (Rf) against photodegradation by quenching the singlet excited states of Rf regardless of the conditions. Also, the complex Mg(phen)(fer) was effectively incorporated into starch films, broadening its applications, as shown by microbiological studies. Thus, Mg(phen)(fer) has high potential for use in Rf-rich foods and to become a new alternative to the synthetic antioxidants currently used.

Alleviation of cadmium toxicity in pea (Pisum sativum L.) through Zn-Lys supplementation and its effects on growth and antioxidant defense

Cadmium significantly impacts plant growth and productivity by disrupting physiological, biochemical, and oxidative defenses, leading to severe damage. The application of Zn-Lys improves plant growth while reducing the stress caused by heavy metals on plants. By focusing on cadmium stress and potential of Zn-Lys on pea, we conducted a pot-based study, organized under completely randomized block design CRD-factorial at the Botanical Garden of Government College University, Faisalabad. Both pea cultivars were grown in several concentrations of cadmium @ 0, 50 and 100 μM, and Zn-Lys were exogenously applied @ 0 mg/L and 10 mg/L with three replicates for each treatment. Cd-toxicity potentially reduces plant growth, chlorophyll contents, osmoprotectants, and anthocyanin content; however, an increase in MDA, H2O2 initiation, enzymatic antioxidant activities as well as phenolic, flavonoid, proline was observed. Remarkably, exogenously applied Zn-Lys significantly enhanced the plant growth, biomass, photosynthetic attributes, osmoprotectants, and anthocyanin contents, while further increase in enzymatic antioxidant activities, total phenolic, flavonoid, and proline contents were noticed. However, application of Zn-Lys instigated a remarkable decrease in levels of MDA and H2O2. It can be suggested with recommendation to check the potential of Zn-Lys on plants under cadmium-based toxic soil.

Dellaglioa spp. an underestimated genus isolated from high-oxygen modified-atmosphere packaged meat

The genus Dellaglioa (D.) actually comprises two species, i.e., D. algida and the recently described species D. carnosa. Both species are adapted to cold and have been typically recovered from meat products. However, their importance has thus far been underestimated, since routine culture-based analysis failed to support their growth. Furthermore, their occurrence on meat packed under high-oxygen MA conditions (HiOx-MAP) is controversial because they have been described as being oxygen-sensitive. In this study, we focused on the targeted isolation of Dellaglioa spp. from HiOx-MAP meat samples and the characterization of our isolates regarding their adaption to HiOx-MAP conditions, their spoilage potential, as well as food safety aspects. We used a medium recently developed specifically for strains of this genus and investigated ten meat batches from seven different suppliers. Our study confirms that the occurrence of Dellaglioa spp. on HiOx-MAP meat is non-sporadic, reaching cell counts ranging from log10 5.8-7.1 CFU/cm2 at a late stage of chilled storage. Autochthonous Dellaglioa spp. and Leuconostoc (L.) gasicomitatum dominated the microbiota of the beef steaks with similar growth behavior. Our results suggest that Dellaglioa spp. benefits from the heme-dependent respiration of oxygen by L. gasicomitatum. Furthermore, whole genome analysis revealed the presence of genes predictively involved in oxidative stress defense, survival, and adaptation in meat environments. Moreover, we predict a weak aminogenic potential of D. algida strains. Tyramine production from tyrosine seems to be a species-specific characteristic of D. carnosa. The extent to which D. algida and D. carnosa occurrence is influenced by or even dependent on the composition of the entire microbiota remains to be investigated.

Development of Yellow Discoloration in Sawai (Pangasianodon hypophthalmus) Muscle due to Lipid Oxidation

In this study, we investigated the impact of lipid oxidation on the discoloration of Sawai (Pangasianodon hypophthalmus) lipids and proteins. Sawai microsomes, liposomes, and salt-soluble myofibrillar proteins were prepared and subjected to lipid oxidation process. The results revealed that the levels of thiobarbituric acid-reactive substances, yellowness (as indicated by b* values), and pyrrole compounds increased when Sawai liposomes and microsomes were oxidized using iron and ascorbate. Meanwhile, the levels of free amines decreased, particularly as the iron content (25∼100 μM) and incubation time (0∼20 h) increased. The impact of oxidized liposomes at different levels (1, 2, and 5%) on the salt-soluble Sawai myofibrillar proteins was also evaluated. The findings revealed that lipid oxidation products reduced the sulfhydryl content and increased the surface hydrophobicity and carbonyl content of the salt-soluble Sawai myofibrillar proteins. These results imply that the formation of yellow discoloration in Sawai muscle could be due to nonenzymatic browning reactions occurring between lipid oxidation products and amines in the muscle protein.

Protein oxidation-mediated changes in digestion profile and nutritional properties of myofibrillar proteins from bighead carp (Hypophthalmichthys nobilis)

Digestibility is an important factor in accessing the nutritional quality and potential health benefits of protein. In this study, exudates were utilized to incubate myofibrillar proteins (MPs) for simulating the oxidation of MPs in frozen-thawed fish fillets. An in vitro gastrointestinal system was used to investigate the effect of protein oxidation on the digestion profile and nutritional properties of MPs. Results showed that exudates treatment caused the moderate oxidation of MPs and its digestibility thus increased, hydroxyl radical generation system treatment reduced the digestibility significantly. The analysis of SDS-PAGE, tricine-SDS-PAGE, amino acid composition, and peptidomics of digestion products indicates that protein oxidation decreases digestibility by causing protein cross-linking, degradation, and amino acid residues conversion. Additionally, protein oxidation reduces nutritional value of MPs via several ways including loss of essential amino acids, the proportion increase of macromolecular peptides (>2 kDa) in digests, and the percentage decrease of potential bioactive peptides in digests. The present study provides an intuitive insight into the impact of protein oxidation in frozen/thawed fillets on the digestibility of MPs, emphasizing the importance of mitigating protein oxidation to preserve their nutritional quality.

Effects of mitochondria on postmortem meat quality: characteristic, isolation, energy metabolism, apoptosis and oxygen consumption

Meat quality holds significant importance for both consumers and meat producers. Various factors influence meat quality, and among them, mitochondria play a crucial role. Recent studies have indicated that mitochondria can sustain their functions and viability for a certain duration in postmortem muscles. Consequently, mitochondria have an impact on oxygen consumption, energy metabolism, and apoptotic processes, which in turn affect myoglobin levels, oxidative stress, meat tenderness, fat oxidation, and protein oxidation. Ultimately, these factors influence the color, tenderness, and flavor of meat. However, there is a dearth of comprehensive summaries addressing the effects of mitochondria on postmortem muscle physiology and meat quality. Therefore, this review aims to describe the characteristics of muscle mitochondria and their potential influence on muscle. Additionally, a suitable method for isolating mitochondria is presented. Lastly, the review emphasizes the regulation of oxygen consumption, energy metabolism, and apoptosis by postmortem muscle mitochondria, and provides an overview of relevant research and recent advancements. The ultimate objective of this review is to elucidate the underlying mechanisms through which mitochondria impact meat quality.

Insight into the protein oxidation impact on the surface properties of myofibrillar proteins from bighead carp

The objective of this study was to elucidate the influence of oxidative modifications of myofibrillar proteins (MPs) on their surface properties. Oxidative modifications (deamination, formation of disulfide bonds and Schiff bases), particle size, net surface charge, and binding ability of volatiles (2-enthylfuran, 1-octen-3-ol, hexanal, and octanal) of oxidized MPs was measured. Molecular docking of volatiles with actomyosin was performed using Qvina-W program and the specific oxidative modifications (monoxidation and deamination) of MPs were determined using LC-MS/MS. Results showed that oxidation of Cys (forming sulfinic, sulfonic, sulfenic acid, and disulfide bonds), monoxidation of Ala, Lys, Glu, and Asn, and deamination of Lys changed the surface properties of oxidized MPs including enhanced surface hydrophobicity and decreased affinity to volatile compounds and water. Overall, this study gives evidence of how protein oxidation affects the properties of MPs and therefore deteriorates fish meat quality.

Effect of Thyme (Thymus vulgaris L.) Used in Diets with Extruded Flaxseed on the Antioxidant and Lipid Profile of the Blood and Tissues of Fattening Pigs

Thyme has strong antioxidant properties and, therefore, can reduce the intensity of oxidative processes taking place in the body. The study aimed to assess whether the addition of thyme to diets for fattening pigs containing extruded flaxseeds, a source of n-3 PUFAs, which are particularly susceptible to oxidation, would have a positive effect on redox status and lipid metabolism. The experiment was conducted using 120 weaners (WBP × Neckar crosses) of about 30 kg BW, which were kept until the end of fattening (about 110 kg BW) and divided into three groups of 40 pigs. The control group received a diet with 4% extruded flaxseed. In groups T1 and T3, 1% or 3% of thyme was added to the basal diet. The introduction of 3% thyme resulted in a decrease in the total cholesterol level in the blood and the loin muscle. Moreover, an increase in SOD and CAT activity and a decrease in FRAP and LOOH was noted. Following supplementation with 3% thyme, the n-3 PUFA content and n-3/n-6 ratio increased, while the SFA content was significantly reduced. The results of the studies indicate that thyme has a positive effect on the redox status and lipid profile of the blood and muscles.

Untargeted Metabolomics Combined with Sensory Analysis to Evaluate the Chemical Changes in Coppa Piacentina PDO during Different Ripening Times

Ripening time is known to drive the chemical and sensory profiles of dry meat products, thus potentially affecting the final quality of the product. Starting from these background conditions, the aim of this work was to shed light, for the first time, on the chemical modifications of a typical Italian PDO meat product-namely, Coppa Piacentina-during ripening, to find correlations between its sensory quality and the biomarker compounds related to the progress of ripening. The ripening time (from 60 to 240 days) was found to deeply modify the chemical composition of this typical meat product, providing potential biomarkers of both oxidative reactions and sensory attributes. The chemical analyses revealed that there is typically a significant decrease in the moisture content during ripening, likely due to increased dehydration. In addition, the fatty acid profile showed that the distribution of polyunsaturated fatty acids significantly (p < 0.05) decreased during ripening, because of their high susceptibility to oxidation and conversion to intermediate and secondary molecules. An untargeted metabolomics approach, coupled with unsupervised and supervised multivariate statistics, highlighted a significant impact (prediction scores > 1) of lipid oxidation during ripening time, with some metabolites (such as γ -glutamyl-peptides, hydroperoxy-fatty acids, and glutathione) being particularly discriminant in predicting the changes observed. The discriminant metabolites were coherent with the progressive increase of peroxide values determined during the entire ripening period. Finally, the sensory analysis outlined that the highest degree of ripening provided greater color intensity of the lean part, slice firmness, and chewing consistency, with glutathione and γ-glutamyl-glutamic acid establishing the highest number of significant correlations with the sensory attributes evaluated. Taken together, this work highlights the importance and validity of untargeted metabolomics coupled with sensory analysis to investigate the comprehensive chemical and sensory changes to dry meat during ripening.

Evaluation of the Antioxidant Properties of Carvacrol as a Prospective Replacement for Crude Essential Oils and Synthetic Antioxidants in Food Storage

The phenolic structural analogues of synthetic antioxidants such as butylated hydroxytoluene (BHT) in essential oils have been reported to exhibit antioxidant properties. Additionally, their lipophilicity makes them suitable for use in lipid-rich foods. This study evaluated the antioxidant capacity of carvacrol, a monoterpenoid antioxidant compound in the Monodora myristica (Gaertn.) seed essential oil, compared to the seed essential oil and BHT. In vitro studies (ferric reducing antioxidant power (FRAP), metal chelating activity (MCA), and nitric oxide scavenging activity (NOSA)) were conducted to ascertain if the antioxidant capacity of carvacrol was comparable to that of the seed essential oil. The potential binding affinity and molecular interactions between carvacrol and lipoxygenase (LOX) and its homologous model were investigated in silico. The molecular docking was performed using Autodock Vina, and the best poses were subjected to molecular dynamics simulation. The IC₅₀ for MCA and NOSA were: carvacrol 50.29 µL/mL, seed essential oil (SEO) 71.06 µL/mL; and carvacrol 127.61 µL/mL, SEO 165.18 µL/mL, respectively. The LOX model was Ramachandran favoured (97.75%) and the overall quality factor in the ERRAT plot was 95.392. The results of the molecular docking and molecular dynamics simulations revealed that lipoxygenase has a higher affinity (-22.79 kcal/mol) for carvacrol compared to BHT. In the LOX-BHT and LOX-carvacrol complexes, the root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), and the radius of gyration (RoG) were not significantly different, indicating similar molecular interactions. The results obtained from this study suggest that carvacrol exhibits an antioxidant capacity that may be explored as an alternative for crude essential oils and synthetic compounds during the storage of lipid-rich foods.

Anti-Inflammatory and Antioxidative Phytogenic Substances against Secret Killers in Poultry: Current Status and Prospects

Chronic stress is recognized as a secret killer in poultry. It is associated with systemic inflammation due to cytokine release, dysbiosis, and the so-called leaky gut syndrome, which mainly results from oxidative stress reactions that damage the barrier function of the cells lining the gut wall. Poultry, especially the genetically selected broiler breeds, frequently suffer from these chronic stress symptoms when exposed to multiple stressors in their growing environments. Since oxidative stress reactions and inflammatory damages are multi-stage and long-term processes, overshooting immune reactions and their down-stream effects also negatively affect the animal's microbiota, and finally impair its performance and commercial value. Means to counteract oxidative stress in poultry and other animals are, therefore, highly welcome. Many phytogenic substances, including flavonoids and phenolic compounds, are known to exert anti-inflammatory and antioxidant effects. In this review, firstly, the main stressors in poultry, such as heat stress, mycotoxins, dysbiosis and diets that contain oxidized lipids that trigger oxidative stress and inflammation, are discussed, along with the key transcription factors involved in the related signal transduction pathways. Secondly, the most promising phytogenic substances and their current applications to ameliorate oxidative stress and inflammation in poultry are highlighted.

Engineered nanomaterials-based sensing systems for assessing the freshness of meat and aquatic products: A state-of-the-art review

Meat and aquatic products are susceptible to spoilage during distribution, transportation, and storage, increasing the urgency of freshness evaluation. Engineered nanomaterials (ENMs) typically with the diameter in the range of 1-100 nm exhibit fascinating physicochemical properties. ENMs-based sensing systems have received extensive attention for food freshness assessment due to the advantages of being fast, simple, and sensitive. This review focuses on summarizing the recent application of ENMs-based sensing systems for food freshness detection. First, chemical indicators related to the freshness of meat and aquatic products are described. Then, how to apply the ENMs including noble metal nanomaterials, metal oxide nanomaterials, carbon nanomaterials, and metal-organic frameworks for the construction of different sensing systems were described. Besides, the recent advance in ENMs-based colorimetric, fluorescent, electrochemical, and surface-enhanced Raman spectroscopy sensing systems for assessing the freshness of meat and aquatic products were outlined. Finally, the challenges and future research perspectives for the application of ENMs-based sensing systems were discussed. The ENMs-based sensing systems have been demonstrated as effective tools for freshness evaluation. The sensing performance of ENMs employed in different sensing systems depends on their composition, size, shape, and stability of nanoparticles. For the real application of ENMs in food industries, the risks and regulatory issues associated with nanomaterials need to be further considered. With the continuous development of nanomaterials and sensing devices, the ENMs-based sensors are expected to be applied in-field for rapid detection of the freshness of meat and aquatic products in the future.

The anti-oxidative potential of ginger extract and its constituent on meat protein isolate under induced Fenton oxidation

Ginger extract has been reported to possess antioxidant properties. However, components isolated from ginger have been rarely reported to inhibit oxidation. Herein, the antioxidant properties of ginger and purified components derived from it (6-gingerol, zingerone, rutin, quercetin, and kaempferol) were confirmed by using HPLC and were further used to investigate its effect on lamb meat. Myofibrillar proteins isolated (MPI) from lamb meat were incubated with ginger and its constituents under induced Fenton oxidation (1.0 mmol/L FeCl3, 0.1 mmol/L Asc, and 20 mmol/L H2O2) for 1, 3,5, and 7 h. Incubating meat protein isolate in the absence of ginger extract or its components resulted in a substantial drop in sulfhydryl groups, an increase in protein carbonyl content, and a corresponding increase in TBARS content. However, ginger extract and its constituents demonstrated antioxidant properties, which might be attributed to their hydroxyl groups and suitable solubilizing side chains. Overall, ginger extract exhibited the highest antioxidant capabilities of all treated samples, suggesting that ginger extracts may be used as a natural antioxidant in meat and lipid/protein-containing processed products. SIGNIFICANCE OF THE STUDY: Ginger extract is also frequently used as a herbal medicine due to its anti-inflammatory, anti-cancer, and antibacterial qualities. Nonvolatile pungent chemicals found in ginger, such as gingerol, shogaols, paradols, and zingerone, as well as kaempferol, rutin, and other phenolic compounds, have been confirmed in ginger extract and have been shown to have antioxidant action driven by free radical elimination. Despite these findings, ginger extract and its pure constituent components have seldom been shown to have the ability to slow protein and lipid oxidation in meat and meat-related products. The effect of ginger extracts on the oxidative stability of myofibriller protein isolate has never been investigated. Exploiting the phenolic content of ginger extract may result in a discovery that would have a huge influence on both the ginger and meat industries as well as other food processing sectors. The first aim of our study was to confirm the presence of six selected phenolic compounds (rutin, kaempferol, 6-gingerol, zingerone, naringenin, and quercetin) in ginger as reported by literature, and the second objective was to determine the efficacy of ginger extracts and its purified constituents on myofibrillar protein isolate treated under induced Fenton oxidation.

Determination of Redox Status in Different Tissues of Lambs and Kids and Their in-between Relationship

The objective of this study was to assess the resting values of the physiological oxidative stress exhibited by lambs and kids reared in Greece, and the potential correlations between redox biomarker levels in blood and other tissues (liver, diaphragm, quadriceps, psoas major muscle). For this purpose, lambs and kids at different developmental stages (d.s.) were used. The latter corresponded to four live weight categories (LWC), each representing 25%, 35%, 70% and 100% of mature body weight. In each of the above tissues, the levels of five common redox biomarkers were determined: glutathione (GSH), catalase (CAT), total antioxidant capacity (TAC), thiobarbituric reactive substances (TBARS), and protein carbonyls (CARBS). The results revealed that lambs and kids belonging to the 35% LWC had weaker endogenous antioxidant pools, while animals in the 70% and 100% LWC had elevated intrinsic antioxidant defense systems. Blood redox biomarkers were associated with the respective ones measured in the diaphragm, liver, quadriceps, and psoas major of both species. Importantly, TBARS levels in blood of animals in the 25% and 100% LWC are correlated with the TBARS levels in all other tissues tested. Blood antioxidant parameters might be used as potential biomarkers to predict the antioxidant status of tissues that affect meat quality. The latter would facilitate quality assessment prior to slaughter, allowing for timely nutritional interventions that can improve meat products.

Integrated Lipidomic and Metabolomics Analysis Revealing the Effects of Frozen Storage Duration on Pork Lipids

Frozen storage is an important strategy to maintain meat quality for long-term storage and transportation. Lipid oxidation is one of the predominant causes of the deterioration of meat quality during frozen storage. Untargeted lipidomic and targeted metabolomics were employed to comprehensively evaluate the effect of frozen duration on pork lipid profiles and lipid oxidative products including free fatty acids and fatty aldehydes. A total of 688 lipids, 40 fatty acids and 14 aldehydes were successfully screened in a pork sample. We found that ether-linked glycerophospholipids, the predominant type of lipids, gradually decreased during frozen storage. Of these ether-linked glycerophospholipids, ether-linked phosphatidylethanolamine and phosphatidylcholine containing more than one unsaturated bond were greatly influenced by frozen storage, resulting in an increase in free polyunsaturated fatty acids and fatty aldehydes. Among these lipid oxidative products, decanal, cis-11,14-eicosenoic acid and cis-5,8,11,14,17-dicosapentaenoic acid can be considered as potential indicators to calculate the freezing time of unknown frozen pork samples. Moreover, over the three-month frozen storage, the first month was a rapid oxidation stage while the other two months were a slow oxidation stage.

In vitro digestion of nitrite and nitrate preserved fermented sausages - New understandings of nitroso-compounds' chemical reactivity in the digestive tract

In vitro digestions of dry-cured sausages formulated with four different rates of added sodium nitrite and sodium nitrate (NaNO₂ / NaNO₃, in ppm: 0/0; 80/80; 120/120; 0/200) were performed with a dynamic gastrointestinal digester (DIDGI®). The chemical reactivity of the potentially toxic nitroso-compounds (NOCs), oxidation reactions products and different iron types were evaluated over time. No nitrite nor nitrate dose effect was observed on NOCs' chemical reactivity. Nitrosothiols were scarce, and nitrosylheme was destabilized for every conditions, possibly leading to free iron release in the digestive tract. Total noN-volatile N-nitrosamines concentrations increased in the gastric compartment while residual nitrites and nitrates remained stable. The minimal rate of 80/80 ppm nitrite/nitrate was enough to protect against lipid oxidation in the digestive tract. The present results provide new insights into the digestive chemistry of dry sausages, and into new reasonable arguments to reduce the load of additives in formulations.

Grapefruit and pomelo peel extracts as natural antioxidants for improved storage stability of Turkey patties during refrigerated storage

The study investigated the effect of albedo and flavedo extracts of grapefruit and pomelo on storage stability of turkey patties during refrigerated storage. Five different types of products were developed depending on the addition of extracts viz. control (C), albedo and flavedo extract of grapefruit (GA and GF), and albedo and flavedo extract of pomelo (PA and PF). The products were stored for 10 days and evaluated for lipid and protein oxidation, pH, colour and sensory properties. The extracts improved the lipid oxidative stability by decreasing (P < 0.05) the TBARS values of the samples compared to control group. No effect of the extract treatments (P > 0.05) was observed on pH and colour values of the products (a* and b*). The lowest TBARS values were found for the products containing GF (0.78 mg MA/kg) on day 4. The treatments showed a significant impact on flavour of the products and the highest scores were obtained for PA containing products.

Studies on antioxidant activities of grape pomace using in vitro, ex vivo, and in vivo models

Grape pomace (GP) is a by-product resulting from the wine industry and can be considered raw material for animal nutrition, mainly due to its richness in polyphenolic substances. The present study, determined the antioxidant activity of GP by different in vitro assays including 1,1-Diphenyl-2-picrylhydrazyl (DPPH), superoxide anion, and hydroxyl radical and hydrogen peroxide scavenging activity and the inhibitory effect on iron-induced lipid peroxidation system. The estimated IC50 value (the concentration required to scavenge 50% of the radicals) of GP methanolic extract was 53.49 mg/L for DPPH; 57.37 mg/L for hydroxyl radical; 29.06 mg/L for superoxide radical and 102.15 mg/L for hydrogen peroxide. The effect of grape pomace supplements in broiler diets on oxidative stability of meat was tested in an experiment on 80 broiler chicks, 1-day-old Cobb 500, divided into 2 groups (C and E) reared on permanent wood shaves litter (10–12 cm thick). Compared to the control diet C, during the grower (14–28 days) and finisher (29–42 days) stages, the experimental diet (E) was supplemented with 6% GP. At the end of the experiment, 6 chicks aged 42 days from each group were slaughtered and samples of thigh meat were collected for further analysis. When the iron-induced lipid peroxidation system was applied, no significant differences were noticed between ex vivo groups’ lipid peroxidation inhibition percentage (24.71% inhibition when GP was added to meat samples and 24.10% inhibition when GP was ingested by animals) and in vivo data (26.92% inhibition) obtained.

Antioxidant and antimicrobial potential of six Fucoids from the Mediterranean Sea and the Atlantic Ocean

BACKGROUD

In recent years, research on the bioactive properties of macroalgae has increased, due to the great interest in exploring new products that can contribute to improve human health and wellbeing. In the present study, the antioxidant and antimicrobial potential of six different brown algae of the Fucales order were evaluated, namely Ericaria selaginoides, Ericaria amentacea, Gongolaria baccata, Gongolaria usneoides, Cystoseira compressa and Sargassum vulgare (collected along the Mediterranean and Atlantic coasts). The antioxidant capacity was measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, the oxygen radical absorbent capacity (ORAC) and the ferric reducing antioxidant power (FRAP) and were related to the total phenolic content (TPC). The antimicrobial activity was evaluated measuring the growth inhibition of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans.

RESULTS

The highest antioxidant capacity was obtained for Ericaria selaginoides revealing the highest capacity to scavenge DPPH radical [half maximal effective concentration (EC50 ) = 27.02 μg mL-1 ], highest FRAP (1761.19 μmol FeSO4 equivalents g-1 extract), high ORAC (138.92 μmol TE g-1 extract), alongside to its high TPC (121.5 GAE g-1 extract). This species also reported the highest antimicrobial capacity against Staphylococcus aureus [half maximal inhibitory concentration (IC50 ) = 268 μg mL-1 ].

CONCLUSIONS

Among all studied seaweed, Ericaria selaginoides reveals the highest antioxidant and antimicrobial activities, and thus should be explored as a natural food additive and/or functional ingredient. © 2022 Society of Chemical Industry.

Strengthening Engineered Nanocrystal Three-Dimensional Superlattices via Ligand Conformation and Reactivity

Nanocrystal assembly into ordered structures provides mesostructural functional materials with a precise control that starts at the atomic scale. However, the lack of understanding on the self-assembly itself plus the poor structural integrity of the resulting supercrystalline materials still limits their application into engineered materials and devices. Surface functionalization of the nanobuilding blocks with organic ligands can be used not only as a means to control the interparticle interactions during self-assembly but also as a reactive platform to further strengthen the final material via ligand cross-linking. Here, we explore the influence of the ligands on superlattice formation and during cross-linking via thermal annealing. We elucidate the effect of the surface functionalization on the nanostructure during self-assembly and show how the ligand-promoted superlattice changes subsequently alter the cross-linking behavior. By gaining further insights on the chemical species derived from the thermally activated cross-linking and its effect in the overall mechanical response, we identify an oxidative radical polymerization as the main mechanism responsible for the ligand cross-linking. In the cascade of reactions occurring during the surface-ligands polymerization, the nanocrystal core material plays a catalytic role, being strongly affected by the anchoring group of the surface ligands. Ultimately, we demonstrate how the found mechanistic insights can be used to adjust the mechanical and nanostructural properties of the obtained nanocomposites. These results enable engineering supercrystalline nanocomposites with improved cohesion while preserving their characteristic nanostructure, which is required to achieve the collective properties for broad functional applications.

Non-melanoma skin cancers: physio-pathology and role of lipid delivery systems in new chemotherapeutic treatments

Non-melanoma carcinoma has high incidence rates and has two most common subtypes: basal cell carcinoma and squamous cell carcinoma. This type of carcinoma is usually not fatal; however, it can destroy sensory organs such as the nose, ears, and lips. The treatment of these injuries using non-invasive methods is thus strongly recommended. Some treatments for non-melanoma carcinoma are already well defined, such as surgery, cryosurgery, curettage and electrode section, and radiotherapy; however, these conventional treatments cause inflammation and scarring. In the non-surgical treatment of non-melanoma carcinoma, the topical administration of chemotherapeutic drugs contributes for an effective treatment with reduced side effects. However, the penetration of anticancer drugs in the deeper layers of the skin is required. Lipid delivery systems (liposomes, solid lipid nanoparticles, nanostructured lipid carriers) have been developed to overcome epidermal barrier of the skin and to allow the drugs to reach tumor cells. These lipid nanoparticles contribute to control the release profile of the loaded chemotherapeutic drugs, maintaining their stability and increasing death of tumor cells. In this review, the characteristics of non-melanoma carcinoma will be discussed, describing the main existing treatments, together with the contribution of lipid delivery systems as an innovative approach to increase the effectiveness of topical therapies for non-melanoma carcinomas.

Free iron rather than heme iron mainly induces oxidation of lipids and proteins in meat cooking

In this study, the relationship between different forms of iron (free or binding) and oxidation of lipids, proteins in meat system were investigated. Pork tenderloin was heated in 80 °C water bath for 0, 30, 60, 120, 180, 240, 300 min. Compared with control group, Equal and Treble deferiprone group confirmed that free iron was the main oxidizing substance. Moreover, adding exogenous heme caused slight increase of meat oxidation (p < 0.05). At the same time, the antioxidant properties of deferiprone were also evaluated and it shows few antioxidant properties. This study also found that the oxidation of lipid by free iron was more serious than protein. These results suggested that controlling free iron and production of free iron from heme is a potential approach for reducing the oxidative damage of lipid and protein in meat cooking.

Encapsulated Microstructures of Beneficial Functional Lipids and Their Applications in Foods and Biomedicines

Beneficial functional lipids are essential nutrients for the growth and development of humans and animals, which nevertheless possess poor chemical stability because of heat/light-sensitivity. Various encapsulation technologies have been developed to protect these nutrients against adverse factors. Different microstructures are exhibited through different encapsulation methods, which influence the encapsulation efficiency and release behavior at the same time. This review summarizes the effects of preparation methods and process parameters on the microstructures of capsules at first. The mechanisms of the different microstructures on encapsulation efficiency and controlled release behavior of core materials are analyzed. Next, a comprehensive overview on the beneficial functional lipids capsules in the latest food and biomedicine applications are provided as well as the matching relationship between the microstructures of the capsules and applications are discussed. Finally, the remaining challenges and future possible directions that have potential interest are outlined. The purpose of this review is to convey the construction of beneficial functional lipids capsules and the function mechanism, a critical analysis on its current status and challenges, and opinions on its future development. This review is believed to promote communication among the food, pharmacy, agronomy, engineering, and nutrition industries.

Application of a Newly Developed Chitosan/Oleic Acid Edible Coating for Extending Shelf-Life of Fresh Pork

This study aimed at evaluating the applicability of a newly-developed chitosan/oleic acid edible coating for extending the shelf-life of fresh pork under aerobic-packaging conditions. Various coating formulations were used: 2% chitosan alone (CHI), 0.5% (v/v) oleic acid in 2% chitosan (CHI/0.5%OA) and 1% (v/v) oleic acid in 2% chitosan (CHI/1%OA) were prepared. For coating, fresh pork slices were fully immersed in the coating solutions for 30 s and dried naturally at 4 °C for 30 min. The coated samples were placed on trays, over-wrapped with plastic film, stored at 4 °C for 21 days, and were analyzed for shelf-life stability. Samples without coating were used as control. It was found that the aerobic bacteria and Pseudomonas spp. counts, and total volatile basic nitrogen (TVBN) content were almost two to three times lower in the CHI/OA-coated samples compared to the control after 21 days of storage (p < 0.05). The CHI/OA coating combination completely inhibited growth of E. coli, and protected the meat from discoloration after 21 days of storage. In particular, the addition of OA increased the concentration of volatiles associated with pleasant aromas. This study provides an application potential of chitosan/oleic acid edible coating in preservation of fresh pork to prolong the shelf-life and improve safety.

Application of bi-layers active gelatin films for sliced dried-cured Coppa conservation

Processed meat products have been increasingly consumed, a highlight being dried-cured coppa, commonly purchased sliced, making it more susceptible to bacterial deterioration and lipid oxidation. The aim of this work was to produce and apply bi-layers films based on gelatin (in both layers) with addition of nisin and/or Pitanga leaf hydroethanolic extract (PLHE) only in the food contact thinner layer, in order to evaluate their effect on the refrigerated storage of sliced dried-cured coppa. Dried-cured coppa slices covered with active films were vacuum-packaged and stored under refrigeration for 120 days. Every 30 days, samples were tested for moisture content, water activity, pH, color parameters, lipid oxidation by TBARS and peroxide index methods, and microbiological analysis. The different film formulations presented no influence on the water activity, pH and color parameters of sliced dried-cured coppa. However, they significantly affected moisture content, bacterial count and lipid oxidation. The addition of both active compounds - nisin and PLHE - in the food contact thinner layer was observed to have the most favorable effect.

Binding mechanism and antioxidant activity of piperine to hemoglobin

Piperine (PIP) is the most active main component in pepper. The interaction of small molecules with biomolecules leads to structural and functional changes. In this study, the binding mechanism and antioxidant activity of PIP with hemoglobin (Hb) are presented using spectroscopic and computational methods. Results showed that the redox activity of PIP on Hb showed concentration dependence. Fluorescence and isothermal titration calorimetric experiments showed that the Hb-PIP system had a static quenching mechanism at a single binding site. The addition of PIP caused a slight perturbation to the secondary structure of Hb by structural analysis. The structural stability of the Hb-PIP binding system was demonstrated by molecular dynamics simulations, and molecular docking and thermodynamic constants confirmed that the electrostatic interaction force was dominant in the energy contribution of the system. Research results are conducive to the potential use of PIP in related meat products.

Effects of oxidized rice bran protein induced by rancidity on the hepatic function in mice

Rice bran protein (RBP) is a great resource of premium protein. However, rice bran (RB) rancidity, which inevitably occurs during rice milling, can induce RBP oxidation, further affecting the nutritional value of RBP. This study focused on the impact of RBP rancidity on the nutritional value of oxidized RBP. RBP with varying oxidation degrees and doses was given to mice via a 12-week intragastric administration. Oxidized RBP interfered with hepatic function and inflammation, and decreased the antioxidant capacities of the liver. Oxidized RBP also disturbed the hepatic lipid metabolism, and excessively oxidized RBP caused intrahepatic lipid accumulation and hepatic damage. Furthermore, oxidized RBP triggered the MyD88/NF-κB pathway but inhibited the Keap1-Nrf2/ARE pathway in the liver. Correlation analysis revealed that the protein expression of the Nrf2 pathway was negatively correlated with the NF-κB pathway. Results implied that oxidized RBP induced hepatic damage and hepatic dysfunction, indicating the deteriorating nutrition of oxidized RBP. The results exhibited the nutritional value of RBP after oxidative modification, and implied the importance of optimizing food-processing strategies to reduce the degree of protein oxidation, thereby avoiding the nutritional loss of dietary protein.

Intracellular imaging of metmyoglobin and oxygen using new dual purpose probe EYFP-Myoglobin-mCherry

The biological relevance of nitric oxide (NO) and reactive oxygen species (ROS) in signaling, metabolic regulation, and disease treatment has become abundantly clear. The dramatic change in NO/ROS processing that accompanies a changing oxygen landscape calls for new imaging tools that can provide cellular details about both [O₂ ] and the production of reactive species. Myoglobin oxidation to the met state by NO/ROS is a known sensor with absorbance changes in the visible range. We previously employed Förster resonance energy transfer to read out the deoxygenation/oxygenation of myoglobin, creating the subcellular [O₂ ] sensor Myoglobin-mCherry. We now add the fluorescent protein EYFP to this sensor to create a novel probe that senses both met formation, a proxy for ROS/NO exposure, and [O₂ ]. Since both proteins are present in the construct, it can also relieve users from the need to measure fluorescence lifetime, making [O₂ ] sensing available to a wider group of laboratories.

Gowda SG, Gowda D, Sakurai T, Sazaki I, Chiba H, Hui SP. Simple and Sensitive Method for the Quantitative Determination of Lipid Hydroperoxides by Liquid Chromatography/Mass Spectrometry

Lipid hydroperoxides (LOOH) are the initial products of the peroxidation of unsaturated lipids and play a crucial role in lipid oxidation due to their ability to decompose into free radicals and cause adverse effects on human health. Thus, LOOHs are commonly considered biomarkers of oxidative stress-associated pathological conditions. Despite their importance, the sensitive and selective analytical method for determination is limited, due to their low abundance, poor stability, and low ionizing efficiency. To overcome these limitations, in this study, we chemically synthesized eight fatty acid hydroperoxides (FAOOH), including FA 18:1-OOH, FA 18:2-OOH, FA 18:3-OOH, FA 20:4-OOH, FA 20:5-OOH, FA 22:1-OOH, FA 22:6-OOH as analytes, and FA 19:1-OOH as internal standard. Then, they were chemically labeled with 2-methoxypropene (2-MxP) to obtain FAOOMxP by one-step derivatization (for 10 min). A selected reaction monitoring assisted targeted analytical method was developed using liquid chromatography/tandem mass spectrometry (LC-MS/MS). The MxP-labelling improved the stability and enhanced the ionization efficiency in positive mode. Application of reverse-phase chromatography allowed coelution of analytes and internal standards with a short analysis time of 6 min. The limit of detection and quantification for FAOOH ranged from 0.1–1 pmol/µL and 1–2.5 pmol/µL, respectively. The method was applied to profile total FAOOHs in chemically oxidized human serum samples (n = 5) and their fractions of low and high-density lipoproteins (n = 4). The linoleic acid hydroperoxide (FA 18:2-OOH) and oleic acid hydroperoxide (FA 18:1-OOH) were the most abundant FAOOHs in human serum and lipoproteins. Overall, our validated LC-MS/MS methodology features enhanced detection and rapid separation that enables facile quantitation of multiple FAOOHs, therefore providing a valuable tool for determining the level of lipid peroxidation with potential diagnostic applications.