Lipid Oxidation Research Articles

Effects of myofibril-palatinose conjugate as a phosphate substitute on meat emulsion quality

The objective of this study was to investigate a replacement for phosphate in meat products. Protein structural modification was employed in this study, and grafted myofibrillar protein (MP) with palatinose was added to meat emulsion without phosphate. Here, 0.15% of sodium polyphosphate (SPP) was replaced by the same (0.15%) concentration and double (0.3%) the concentration of grafted MP. Although the thermal stability was decreased, the addition of transglutaminase could increase stability. The rheological properties and pH also increased with the addition of grafted MP and transglutaminase. The addition of grafted protein could be perceived by the naked eye by observing a color difference before cooking, but it was not easy to detect after cooking. The cooking loss, emulsion stability, water holding capacity, lipid oxidation, and textural properties improved with the addition of grafted MP. However, the excessive addition of grafted MP and transglutaminase was not recommended to produce a high quality of phosphate replaced meat emulsion, and 0.15% was identified as a suitable addition ratio of grafted MP.

Effect of heme proteins on the lipid molecule profile and aroma formation during hot air drying of non-smoked bacon

Heme proteins and their derivatives play important roles in inducing lipid oxidation to produce volatile compounds during bacon drying. This study investigated the effects of heme proteins and their derivatives (hemoglobin, myoglobin, nitrosylmyoglobin, hemin, Fe2+, and Fe3+) on lipid and volatiles profiles in the washed pig muscle (WPM) model. The results of the study indicated that the inducers primarily caused the oxidation of glycerophospholipids. Furthermore, hemoglobin and myoglobin had the most significant impact, and their potential substrates may include PE (O-18:2/20:4), PE (O-18:1/20:4), PC (16:0/18:1), and PE (O-18:2/18:2). Nitrosomyoglobin has limited ability to promote lipid oxidation and may protect ether phospholipids from oxidation. The analysis of the volatiles in the model revealed that heme proteins and their derivatives have the ability to induce the production of key aroma compounds. The descending order of effectiveness in inducing the production of aroma compounds is as follows: hemoglobin, myoglobin, hemin, and nitrosylmyoglobin. The effectiveness of Fe2+ and Fe3+ is similar to that of nitrosylmyoglobin.

Determination of Biogenic Amine Level Variations upon Storage, in Chicken Breast Coated with Edible Protective Film.

A new chitosan-based protective film containing rosemarinic acid (0.282% w/w) has been elaborated. The film was formed from a water-oil emulsion system and applied to poultry meat samples using a dip-coating technique. Various physicochemical parameters of the coatings, such as thickness, Young's modulus, elongation at break, water vapor transmission rates, and antioxidant activity, were tested with free-standing film samples peeled from a Petri dish. Compared to neat chitosan films obtained similarly, new films cast from the emulsion showed significantly better elasticity (Young's modulus was diminished from 1458 MPa to about 29 MPa). Additionally, barrier properties for moisture transition decreased from 7.3 to 5.8 g mm m-2 day-1 kPa-1. The coated poultry samples were subsequently evaluated in juxtaposition with uncoated ones in a storage test. Levels of selected biogenic amines (histamine, tyramine, tryptamine, phenylethylamine, putrescine, cadaverine, spermine, and spermidine), total bacterial count, and lipid oxidation levels in the meat samples were analyzed during storage at 4 °C (up to 96 h). The results obtained for the biogenic amines, total bacterial content, calculated biogenic amine index, and the ratio of spermidine to spermine in meat samples suggest the advantage of the proposed coatings with rosmarinic acid in protecting poultry meat against environmental factors and rapid spoilage.

Oxidative modification products of lipids in the intraocular fluid of patients with cataracts associated with chronic non-infectious diseases

Introduction. To clarify the role of oxidative stress in the development of cataracts, it is necessary to determine the content of oxidative modification products directly in the eye tissue, but such studies are scarce, which is due to the difficulty of obtaining a sufficient amount of biomaterial for analysis and the need to use highly sensitive research methods as a result. Therefore, to assess the pathological changes in the lens, intraocular or tear fluid is used.Aim. To elucidate the role of oxidative stress in the development of cataracts by determining the content of lipid oxidation products and their comparative characteristics in intraocular fluid and in blood plasma in patients with cataracts associated with chronic non-infectious diseases.Materials and methods. The study involved 83 patients with cataracts associated with non-infectious diseases, who underwent surgical treatment. Of these, 30 patients had chronic obstructive pulmonary disease (COPD) as a comorbid condition, 45 had cardiovascular diseases (CVD), and 13 had diabetes mellitus (DM). The control group consisted of 30 practically healthy individuals without clinical signs of acute or chronic diseases. Lipid oxidation products were determined by ultraviolet spectroscopy. Absorption spectra of non-oxidized lipids (E204), diene conjugates (E233), conjugated trienes, and ketodiene (E278) were recorded. Additionally, the ratios of absorption spectra of diene conjugates to non-oxidized lipids (E233/E204), as well as conjugated dienes and ketodienes to non-oxidized lipids (E278/E204), were calculated. Tear and intraocular fluids, as well as blood plasma, served as materials for the study.Results. In the group of patients with cataracts associated with non-infectious diseases, the content of diene conjugates, conjugated trienes, and ketodienes was increased relative to similar indicators in the tear fluid of people in the control group. Moreover, more pronounced changes were observed in the group of patients with cataracts associated with COPD relative to those with CVD and DM. A comparative analysis confirmed that in the group of patients with cataracts associated with COPD, the content of oxidized lipids in intraocular fluid and in blood plasma was increased. Correlation-regression analysis showed a positive relationship between the indicators of diene conjugates in intraocular fluid and in blood plasma.Conclusions. The significant direct linear relationship between the indicators of oxidized lipids in intraocular fluid and in blood plasma in patients with cataracts and non-infectious diseases may indicate the possibility of using blood plasma for studying oxidative processes in the lens and its pathological changes for the purpose of selecting therapy and evaluating treatment efficacy. The results obtained confirm the role of oxidative stress in the development of cataracts in patients with chronic non-infectious diseases.

Abstract 430: Precision diet and lipid modulating agents to induce lipid oxidation in breast cancer

Abstract Metastasis is the primary cause of breast cancer-related mortality, and understanding the intricate relationship between the tumor microenvironment, lipid metabolism, and metastasis is crucial for preventing cancer progression. Previous work from our group demonstrated that high exogenous levels of oleic acid, a monounsaturated fatty acid (MUFA), in the lymph node environment protects melanoma cells from ferroptosis. Ferroptosis is an iron-dependent form of cell death induced by accumulation of lipid peroxides, which are commonly formed from polyunsaturated fatty acids (PUFAs), but not MUFAs. Here, we hypothesized that increasing dietary PUFAs would alter the exogeneous lipid content of the lymph node environment, thus rendering breast cancer cells more sensitive to ferroptosis. To test this, we determined the in vitro sensitivity of 4T1 triple negative breast cancer cells to ferroptosis when treated with various PUFAs and MUFAs. We also assessed the impact of various PUFA and MUFA fatty acid-enriched diets on breast cancer metastasis and ferroptosis resistance in the lymph nodes in vivo. In concordance with previously published work, our results demonstrated that pharmacological induction of ferroptosis in vitro increased lipid oxidation and was mitigated by fatty acid treatments with higher MUFA compared to PUFA content. In vivo, cancer cells in lymph nodes of mice on palm oil diets had lower lipid oxidation compared to cancer cells from tumors in the mammary fat pad. These findings support the hypothesis that dietary lipids can alter ferroptosis response and the extent of lipid oxidation in breast cancer cells within lymph nodes. Our research has the potential to further reveal mechanistic connections between dietary lipids, the lymphatic microenvironment, and breast cancer progression. Citation Format: Mahsa Yavari, Jordan Torpey, Marie Sabatier, Alanis Carmona, Krystina Szylo, Midori Flores, Mario Palma, Cameron Fraser, Yanshan Liang, Sheng Tony Hui, Oana Zeleznik, Heather Eliassen, Jessalyn Ubellacker. Precision diet and lipid modulating agents to induce lipid oxidation in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 430.

The improvement of storage quality of Harbin red sausage by coating with oregano essential oil loaded zein-pectin-chitosan nanoparticles

The effect of coating of oregano essential oil loaded zein pectin chitosan nanoparticles (Zein-PC-CS-OEO) to improve the quality of Harbin red sausage during storage was investigated. Firstly, Zein-PC-CS-OEO nanoparticles were prepared and characterized. Subsequently, Zein-PC-CS-OEO nanoparticles (EN-OEO) added sodium alginate solutions were successfully coated on the Harbin red sausage at different concentrations. All the sausages were stored at 20 °C and 65% relative humidity for 12 d, and subsequently sampled at 0, 3, 6, 9, and 12 d. The physicochemical properties, total number of aerobic bacteria, bacterial community structure and flavor characteristics for the Harbin red sausage were measured. Both lipid oxidation and the growth of dominant spoilage bacteria in Harbin red sausage are inhibited by EN-OEO coating, while the total aerobic bacteria count is reduced. These results indicate that the storage quality of Harbin red sausage is improved by EN-OEO coating. It is worth noting that the shelf life of the Harbin red sausage with 3% EN-OEO coating is extended to 9 d and the flavor characteristics of Harbin red sausage can be better preserved compared with the Control sample and the unencapsulated samples. This study provides a new thought for the preservation of Harbin red sausage as well as other low-temperature meat products.

Effect of Nonprotein Components for Lipid Oxidation in Emulsions Stabilized by Plant Protein Extracts.

Plant protein ingredients are rich in non-protein components of which the antioxidant and pro-oxidant effects are expected to be considerable. In this paper, commercial soy and pea protein isolates and concentrates were selected by using their soluble fractions to prepare oil-in-water (O/W) emulsions. Emulsions stabilized with soy protein isolates were more prone to lipid oxidation than those with soy protein concentrate or pea protein isolate. Compositional analysis revealed that the soluble fraction of soy protein isolates contained higher concentrations of phenolic compounds and metals (iron and copper) but lower mineral and ash contents than those of soy protein concentrate and pea protein isolate. Correlating the composition to oxidation in emulsions highlighted the significant role of non-protein components, alongside the protein's oxidative state. These findings are relevant for the use of alternative proteins in food formulation, a practice often promoted as sustainable yet that may come with repercussions for oxidative stability.

Exploring the molecular biology of ischemic cardiomyopathy based on ferroptosis‑related genes.

Ischemic cardiomyopathy (ICM) is a serious cardiac disease with a very high mortality rate worldwide, which causes myocardial ischemia and hypoxia as the main damage. Further understanding of the underlying pathological processes of cardiomyocyte injury is key to the development of cardioprotective strategies. Ferroptosis is an iron-dependent form of regulated cell death characterized by the accumulation of lipid hydroperoxides to lethal levels, resulting in oxidative damage to the cell membrane. The current understanding of the role and regulation of ferroptosis in ICM is still limited, especially in the absence of evidence from large-scale transcriptomic data. Through comprehensive bioinformatics analysis of human ICM transcriptome data obtained from the Gene Expression Omnibus database, the present study identified differentially expressed ferroptosis-related genes (DEFRGs) in ICM. Subsequently, their potential biological mechanisms and cross-talk were analyzed, and hub genes were identified by constructing protein-protein interaction networks. Ferroptosis features such as reactive oxygen species generation, changes in ferroptosis marker proteins, iron ion aggregation and lipid oxidation, were identified in the H9c2 anoxic reoxygenation injury model. Finally, the diagnostic ability of Gap junction alpha-1 (GJA1), Solute carrier family 40 member 1 (SLC40A1), Alpha-synuclein (SNCA) were identified through receiver operating characteristic curves and the expression of DEFRGs was verified in an in vitro model. Furthermore, potential drugs (retinoic acid) that could regulate ICM ferroptosis were predicted based on key DEFRGs. The present article presents new insights into the role of ferroptosis in ICM, investigating the regulatory role of ferroptosis in the pathological process of ICM and advocating for ferroptosis as a potential novel therapeutic target for ICM based on evidence from the ICM transcriptome.

Biochemical Investigation of Therapeutic Efficacy of Berberine-Enriched Extract in Streptozotocin-Induced Metabolic Impairment.

Metabolic disorders pose significant global health challenges, necessitating innovative therapeutic approaches. This study focused on the multifaceted therapeutic potential of berberine-enriched extract (BEE) in mitigating metabolic impairment induced by streptozotocin (STZ) in a rat model and compared the effects of BEE with berberine (BBR) and metformin (MET) to comprehensively evaluate their impact on various biochemical parameters. Our investigation reveals that BEE surpasses the effects of BBR and MET in ameliorating metabolic impairment, making it a promising candidate for managing metabolic disorders. For this, 30 male Wistar rats were divided into five groups (n = 6): control (CN), STZ, STZ + MET, STZ + BBR, and STZ + BEE. The treatment duration was extended over 4 weeks, during which various biochemical parameters were monitored, including fasting blood glucose (FBG), lipid profiles, inflammation, liver and kidney function biomarkers, and gene expressions of various metabolizing enzymes. The induction of metabolic impairment by STZ was evident through an elevated FBG level and disrupted lipid profiles. The enriched extract effectively regulated glucose homeostasis, as evidenced by the restoration of FBG levels, superior to both BBR and MET. Furthermore, BEE demonstrated potent effects on insulin sensitivity, upregulating the key genes involved in carbohydrate metabolism: GCK, IGF-1, and GLUT2. This highlights its potential in enhancing glucose utilization and insulin responsiveness. Dyslipidemia, a common occurrence in metabolic disorders, was effectively managed by BEE. The extract exhibited superior efficacy in regulating lipid profiles. Additionally, BEE exhibited significant anti-inflammatory properties, surpassing the effects of BBR and MET in lowering the levels of inflammatory biomarkers (IL-6 and TNF-α), thereby ameliorating insulin resistance and systemic inflammation. The extract's superior hepatoprotective and nephroprotective effects, indicated by the restoration of liver and kidney function biomarkers, further highlight its potential in maintaining organ health. Moreover, BEE demonstrated potent antioxidant properties, reducing oxidative stress and lipid peroxidation in liver tissue homogenates. Histopathological examination of the pancreas underscored the protective effects of BEE, preserving and recovering pancreatic β-cells damaged by STZ. This collective evidence positions BEE as a promising therapeutic candidate for managing metabolic disorders and offers potential benefits beyond current treatments. In conclusion, our findings emphasize the remarkable therapeutic efficacy of BEE and provide a foundation for further research into its mechanisms, long-term safety, and clinical translation.

Quinoa seed: A source of lipophilic nutraceuticals for the prevention of metabolic syndrome in a rat model

Metabolic syndrome (MS) is a cluster of metabolic changes including hypertriglyceridemia, elevated glucose tolerance and fatty liver. The aim of this research was to study the bioactivity of petroleum ether extracts prepared from quinoa 1 and Hualhuas quinoa in a MS rat model. Fatty acids and α-tocopherol were assessed in the extracts. MS was induced by feeding a high fructose-high fat diet (HFFD). Four groups of rats were assigned: the control group, fed a balanced diet; the control group, fed a HFFD diet; and two test groups, fed on a HFFD diet and treated by either quinoa 1 or hualhuas extract. The Glucose tolerance, plasma lipids, oxidative stress biomarkers, liver lipids and histopathology of the liver and heart were assessed. The results showed that extracts from both quinoa varieties had the potential to prevent MS; although quinoa 1 was more effective. In both varieties, the major fatty acid was linoleic. Hualhuas showed a higher percentage of linolenic acid than quinoa 1; while more alpha-tocopherol was present in quinoa1.

Integrated analysis of transcriptomic and physiological responses to cold stress in Macrobrachium rosenbergii

The giant freshwater prawn (GFP), Macrobrachium rosenbergii, stands out as a vital species in freshwater shrimp aquaculture. However, its susceptibility to cold conditions has increased the cost of aquaculture and limited the growth of GFP cultivation. To furnish insights at the molecular level to enhance GFP's cold tolerance, transcriptome sequencing and physiological analysis of the hepatopancreas were performed in our study. Initially, we identified 4909 differentially expressed genes (DEGs) between experimental (15 °C, 24 h) and control groups (25 °C, 24 h). These DEGs were significantly enriched in the proteasome, spliceosome, lysosome, peroxisome, and lipid metabolism-related pathways including glycerolipid metabolism, sphingolipid metabolism, linoleic acid metabolism as well as steroid hormone biosynthesis. Histological examination following various stress durations revealed a notable increase in hepatocyte vacuoles after 6 h of cold stress. Hepatocyte structure deterioration occurred in the later phase (48 h), coinciding with a significant increase in cell apoptosis. Subsequent analyses demonstrated an initial increase followed by a decrease in superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) content, while malonaldehyde (MDA) content rose with stress duration. Furthermore, a significant increase in triglyceride content and no significant change in cholesterol content was observed. RT-qPCR results unveiled significant down-regulated expression of FAS, TAGL, ACOX1, ACS and significant up-regulated expression of GPAT and DEGS. These findings suggest that oxidative stress and impaired lipid metabolism underlie the poor cold tolerance of GFP.

Abstract 5993: Temporal dynamics of ferroptosis vulnerability in a resistant cancer cell state

Abstract Once cancer has metastasized it remains incurable as a result of evolved resistance to nearly all systemic therapies. Our group has demonstrated that an endocycling cancer cell state is an underappreciated mechanism of therapeutic resistance in many cancer settings. Cells in this state uncouple DNA replication from cell division to obtain abnormally high genomic content and cell size (over 40x volume). Resulting polyploidy and cellular hypertrophy provide survival advantages such as elevated genomic content, higher oxidative buffer capacity, increased autophagy, and heightened resistance to chemotherapy. Endocycling cancer cells are induced by multiple different classes of chemotherapy and present in vivo at increased frequencies both in metastatic sites and following chemotherapy. We hypothesize elimination of this overlooked resistant cancer cell state is critical for sustained anticancer therapies. Cancer cells, including those in the endocycling cancer cell state, leverage canonical cell cycle and cell death programs to evade apoptosis from external stressors including all classes of chemotherapy. Engaging cell cycle-independent death pathways is an alternative therapeutic strategy that circumvents cancer’s trademark manipulation of the cell cycle1. Ferroptosis is a cell cycle agnostic form of cell death that occurs due to dysregulation of cellular iron and subsequent lipid peroxidation. While ferroptosis is emerging as a vulnerability in resistant cancers, efficacy of ferroptosis induction is highly heterogeneous depending on tissue type, cellular metabolism, and many other factors. We characterized oxidative damage, labile iron, lipid content, and signaling pathways in cells pre- and post-chemotherapy to assess vulnerability to ferroptosis. By inhibiting GPX4, the sole lipophilic antioxidant enzyme, we show induction of ferroptotic cell death across multiple cell lines and chemotherapies with cells in the endocycling state being more susceptible. Importantly, targeting cells in the endocycling cancer cell state (as opposed to untreated cell lines), also affords a more uniform elimination by ferroptosis. Ferroptosis also has a capacity to be immunogenic that may direct anti-cancer immune licensing in addition to direct cytotoxicity. These studies will directly contribute to development of ferroptosis engaging therapeutic strategies for resistant cancer cell states, particularly concerning the timing of intervention. 1Loftus, L.V.; Amend, S.R.; Pienta, K.J. Interplay between Cell Death and Cell Proliferation Reveals New Strategies for Cancer Therapy. Int. J. Mol. Sci. 2022, 23, 4723. https://doi.org/10.3390/ijms23094723 Citation Format: Luke Loftus, Ken Pienta, Sarah Amend. Temporal dynamics of ferroptosis vulnerability in a resistant cancer cell state [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5993.

Effect of marinating with green tea extract on the safety and sensory profiles of oven-baked oyster

Baked oyster is a popular seafood dish around the world. The present study investigated the effect of various concentrations of a green-tea extract (GTE) marinade on the safety and sensory profiles of oysters baked for different durations. The results showed 10 g/L of GTE and 10-min baking time was the optimal combination, as supported by significantly attenuated lipid oxidation (35.29 %) and Nε-(carboxyethyl)lysine (CEL) content (48.51 %) without appreciable negative impact on the sensory or nutritional quality of the oysters. However, high concentrations of the marinade or prolonged baking promoted protein oxidation and Nε-(carboxymethyl)lysine (CML) formation likely through the pro-oxidative action of the GTE phytochemicals. Correlation analysis further revealed the main factors that affected CML, CEL, and fluorescent AGEs generation, respectively. These findings provide theoretical support for the protective effect and mechanism of GTE against quality deterioration of baked oysters and would help broaden the application of GTE in the food industry.

Monitoring of changes in the concentration of volatile organic compound in beef irradiated with accelerated electrons

The need to develop safe methods for radiation processing of food products to improve their quality and extend their shelf life stimulates new scientific research aimed at increasing their effectiveness. Oxidation of lipids and proteins occurred under the impact of ionizing radiation in products with a high fat and water content, such as chilled meat and fish products, leads to the formation of volatile organic compounds in the product thus giving it a specific smell and taste. During storage, biochemical processes associated with microbial enzymatic activity and auto-oxidation develop in processed refrigerated products. These processes also modify the volatile organic compounds, which affect the organoleptic properties of the product. The method of gas chromatography-mass spectrometry was used to study the behavior of volatile compounds identified in irradiated beef samples both immediately after irradiation and four days later to determine the effective dose range for the radiation processing of beef. Monitoring of the content of volatile compounds in beef samples irradiated by 1-MeV electrons within a dose range from 0.25 to 5 kGy showed that the content of certain alcohols, aldehydes, and alkanes exhibited pronounced dose- and time-dependent character. The developed mathematical model describes the dependence of the concentration of volatile compounds identified immediately after irradiation in beef samples on the irradiation dose. The model is based on the simultaneous occurrence of two competing processes: the decomposition of compounds due to their oxidation and accumulation due to oxidation of other compounds after exposure to ionizing radiation. The results obtained revealed that the effective dosage range of radiation treatment lies between 250 and 1000 Gy.

Disclosing the Functional Potency of Three Oxygenated Monoterpenes in Combating Microbial Pathogenesis: From Targeting Virulence Factors to Chicken Meat Preservation.

During the last few decades, there has existed an increased interest in and considerable consumer preference towards using natural and safe compounds derived from medicinal plants as alternatives to synthetic preservatives to combat microbial pathogenicity. In this regard, the present study investigated the possible synergistic interactions of the anti-foodborne bacterial capacity of linalool (L), eucalyptol (E), and camphor (C). The antibacterial synergistic effect was determined against Staphylococcus aureus, Listeria monocytogenes, Salmonella enterica Typhimurium, and Escherichia coli. The optimal predicted mixture showed the highest antibacterial activity at 33.5%, 33.2%, and 33.4% of L, E, and C, respectively. Molecular docking simulations displayed that the studied monoterpenes have effective antibacterial inhibitory effects by impeding specific virulence factors such as sortase A, listeriolysin O, L, D-Transpeptidase, and polyphosphate kinase. The selected triple combination of L, E, and C was applied as a natural preservative in minced chicken breast meat. In this regard, 1 MIC (16 µg/mL), 1.5 MIC (24 µg/mL), and 2 MIC (32 µg/mL) of L. monocytogenes were used, and the microbiological, physicochemical, and sensory analyses were monitored for 14 days of storage at 4 °C. The L/E/C mixture at different levels could delay lipid and protein oxidation, inhibit the microorganisms, and maintain the sensory attributes. Additionally, by using chemometric tools, strong connections between physicochemical properties, microbiological parameters, and organoleptic attributes were established. Concisely, this research confers the importance of the use of blended monoterpenes and highlights their antibacterial mode of action, effectiveness, and synergistic effects as a powerful and safe bio-preservative formulation in chicken meat products.

Application of Antioxidant Poly-Lactic Acid/Polyhydroxybutyrate (PLA/PHB) Films with Rice Bran Extract for the Preservation of Fresh Pork Meat.

Poly-lactic acid/polyhydroxybutyrate (PLA/PHB) bio-based films suppose an environmentally friendly alternative to petroleum-derived packaging. In addition, rice bran extracts (RBEs) are an interesting source of bioactive compounds. In the present study, active films were formulated with 0.3% (w/v) or 0.5% (w/v) RBE (low-RBE and high-RBE) and compared to PLA/PHB films with no RBE. The migrations of active compounds as well as the antimicrobial and the antioxidant activities were analyzed in the three film formulations. The effects of active PLA/PHB films on fresh pork meat were evaluated by measuring the instrumental color, lipid and protein oxidations, and microbiological status of meat refrigerated for 1, 5, or 9 days. The developed films presented antioxidant activity in vitro, but they did not have an antimicrobial effect against bacterial development (E. coli nor L. innocua). The PLA/PHB film with no extract prevented changes in the instrumental color of meat during storage. However, the antioxidant effect of the PLA/PHB films on fresh pork was negligible, and the inclusion of high doses of extract favored microbial development in the pork during storage. Despite the lack of activity of active PLA/PHB films on meat, their use could be a sustainable alternative to the petroleum-based films.

Physio-biochemical responses of rice to smart nitrogen fertilizer nano-hydrogel under drought stress and flooding alternation: An eco-friendly innovative approach to enhance the grain quality

Fertilizer nanohydrogels have been newly introduced to agriculture. Herein, we investigated the effects of smart nitrogen (N) fertilizer nano-hydrogel on rice's physio-biochemical traits and seed quality under different drought stress and flooding conditions. Therefore, a pot experiment was conducted with no N fertilizer delivery 0 g N/kg (NND), with conventional N fertilizer delivery 0.175 g N/kg (CND), and smart N fertilizer delivery 0.175 g N/kg (SND) using three irrigation options: flooding/moderate dryness (FMD, 90% saturation, 30 mm submerged), flooding/sharp dryness (FSD, 70% saturation, 30 mm submerged), and flooding/extreme dryness (FED, 50% saturation, 30 mm submerged). Results showed that rice root's active acquisition area and enzymatic activity were larger in FMD × SND than in FED × NND, as the former combination increased NH4+, NO3−, and TN contents in the soil while the latter reduced their availability. The optimal N nutrition improved the plant cell ultrastructure, and the catalase activity was higher in the FMD × SND (42.0 µg/min) compared to the FED × NND (25.2 µg/min), leading to the alleviation of oxidative cell injury, as verified by lesser radical oxidative sequences and lipid peroxidation. The leaf soluble protein (8.8 mg/g) and sugar (36.9 mg/g) were greater in FMD × SND than in FED × NND (5.3 mg/g), (10.4 mg/g), and (8.3 µg/g h), respectively. Moreover, α-amylase and glutamine synthetase activities were larger in the FMD × SND than in FED × NND. Meanwhile, the FMD × SND resulted in the highest milled rice (87.3%), amylose (17.6%), protein (12.4%), and fatty acids (11.1%). However, the combination of FED × NND led to the lowest milled rice (70.0%), amylose (5.6%), protein (5.3%), and fatty acids (6.6%). This study suggests that the FMD × SND can guarantee physio-biochemical improvements in rice, thereby increasing grain quality.

Effect of wet-aging on meat quality and exudate metabolome changes in different beef muscles

The aim of this study was to evaluate meat quality and changes in the meat exudate metabolome of different beef muscles (5 d postmortem, longissimus lumborum and psoas major muscles) during wet-aging (additional 3, 7, 14, 21, and 28 d of aging). Shear force of meat declined significantly (P < 0.001) with aging, meanwhile, increased myofibril fragmentation index, lipid and protein oxidation with aging were observed (P < 0.01). Psoas major (PM) showed significantly higher (P < 0.05) purge loss, centrifugal loss, and cooking loss, as well as higher tenderness and more severe lipid and protein oxidation (P < 0.01) than longissimus lumborum (LL) during aging. Principal component analysis of the metabolomic profiles revealed distinct clusters according to the period of aging and the type of muscle simultaneously. Overabundant amino acids, peptides, oxidized fatty acids, and hydroxy fatty acids were found in long-term aged meat exudates, and forty metabolites were significantly correlated with meat quality characteristics. Fifty-nine metabolites were significantly affected by muscle type. These results demonstrated the potential possibility of evaluating meat quality using meat exudate metabolomics.

Depth-profiling alkyl chain order in unsaturated lipid monolayers on water.

Unsaturated lipids with C=C groups in their alkyl chains are widely present in the cell membrane and food. The C=C groups alter the lipid packing density, membrane stability, and persistence against lipid oxidation. Yet, molecular-level insights into the structure of the unsaturated lipids remain scarce. Here, we probe the molecular structure and organization of monolayers of unsaturated lipids on the water surface using heterodyne-detected sum-frequency generation (HD-SFG) spectroscopy. We vary the location of the C=C in the alkyl chain and find that at high lipid density, the location of the C=C group affects neither the interfacial water organization nor the tail of the alkyl chain. Based on this observation, we use the C=C stretch HD-SFG response to depth-profile the alkyl chain conformation of the unsaturated lipid. We find that the first 1/3 of carbon atoms from the headgroup are relatively rigid, oriented perpendicular to the surface. In contrast, the remaining carbon atoms can be approximated as free rotators, introducing the disordering of the alkyl chains.

Black Soldier Fly Oil in Different Lipid Diets Could Regulate Tissue Lipid Metabolism and Fatty Acid Composition of Juvenile Mirror Carp

In the present study, our aim was to assess the effect of dietary black soldier fly oil (BSFO) with different lipid contents on the growth performance, body composition, lipid metabolism, and related gene expression in juvenile mirror carp (Cyprinus carpio var. specularis). An 8-week feeding trial was conducted using four isonitrogenous diets (32.0% crude protein) containing two lipid levels: 6% (control (CT) group) and 9% (high lipid (HL) group), both using soybean oil as the oil source. The other two diets contained BSFO on the basis of 6% and 9% lipid, referred to as (CT + BSFO) and (HL + BSFO) groups. The results showed that final body weight, weight gain rate, specific growth rate, protein retention ratio, and feed utilization were significantly increased by using higher dietary lipid levels (P&lt;0.05). Additionally, the gene expression of lipid synthesis markers was significantly up-regulated in intra-peritoneal fat but significantly down-regulated in the hepatopancreas due to increased dietary lipid level (P&lt;0.05). No negative effects on feed utilization or growth performance were observed in fish fed diets containing BSFO. However, the intra-peritoneal fat index, adipocyte size, and hepatopancreas lipid content were significantly decreased in the CT + BSFO group compared to the CT group (P&lt;0.05). Furthermore, BSFO also up-regulated the expression of lipid lipolysis markers in the hepatopancreas and intra-peritoneal fat (P&lt;0.05). Moreover, the use of BSFO also increased the content of n-3 polyunsaturated fatty acid (PUFA) while reducing the content of n-6 PUFA in the muscle (P&lt;0.05). In conclusion, HL diets improved the growth of the fish and increased the lipid deposition. BSFO in the diet resulted in a reduction of lipid deposition in the hepatopancreas and intra-peritoneal fat, likely due to an increase in lipid oxidation.