Elderberry (Sambucus nigra L.) Encapsulated Extracts as Meat Extenders against Lipid and Protein Oxidation during the Shelf-Life of Beef Burgers

Metabolic profiling and antidiabetic potential of Oedogonium angustistomum, Ulothrix variabilis, and Mougeotia pulchella and their peptides targeting α-amylase and α-glucosidase: In vitro and in silico approaches

The present research aimed to examine the diabetes-fighting properties of three algal species: Oedogonium angustistomum, Ulothrix variabilis, and Mougeotia pulchella. The in vitro antidiabetic properties of these algae were investigated by α-amylase and α-glucosidase inhibition assays. The metabolites responsible for the inhibition of α-amylase (2QV4) and α-glucosidase (8YIE) were identified through molecular docking and molecular dynamic simulation in the Maestro V 13.2, Schrödinger suite. In the in vitro research, aqueous, methanol, and petroleum benzene-derived extracts of M. pulchella demonstrated significant inhibition of α-amylase and α-glucosidase, with IC50 values of 19.58, 16.67 μg/mL, and 16.43 μg/mL, respectively. In this research, approximately 62 chemical constituents belonging to various classes were identified by LC-MS. In the in-silico research, the peptides, namely 2-(S-Glutathionyl) acetyl glutathione, APGPR enterostatin, and endomorphine 2, were found to exhibit greater efficacy, with docking scores of -8.053, -8.564, and -7.653 kcal/mol respectively. Furthermore, molecular dynamics simulations demonstrated that the complexes exhibited a lower RMSD range of ≤2.8, indicating enhanced stability. Therefore, this study concludes that the peptides may serve as potential candidates for the development of anti-diabetic agents. However, further in vivo research is required to understand the mechanisms of action of peptides in diabetic experiments.

Unveiling the Potential of Southern Elderberry (Sambucus australis): Characterization of Physicochemical Properties, Carbohydrates, Organic Acids and Biophenols

Sambucus australis is a wild species with purple fruits like berries. It is native from South America and can be found in Argentina, Uruguay, Paraguay, Bolivia, and Brazil. A comprehensive characterization of S. australis fruiting period and ripening could provide valuable information on the stage of development suitable for formulating typical and new food and cosmetic products, as well as it could contribute to reveals its nutritional value. This study aimed to examine the evolution of fruit size and weight alongside the accumulation patterns of sugars, organic acids, biophenols and antioxidant activity during different development stages of S. australis fruit, assessing its potential as a source of health-promoting compounds. The increase in total sugar (269.59 g/kg dry weight), together with the decrease in the total organic acids (321.63 g/kg dry weight) at the fully ripe stage, indicates that the fruit is sweet. This suggests that it is an appealing product to be consumed when it is fully ripe. The fatty acid composition contains significant levels of α-linolenic, linoleic, oleic and palmitic acids. It is characterized by high ratios of polyunsaturated fatty acids to saturated fatty acids, ranging from 5.8 to 6.4. S. australis fruits appeared to possess good levels of biophenols at fully ripe fruits (4709.7 µg/g dry weight) together with antioxidant activity (higher than 80%), so, it could be considered as a functional food.

Protein oxidation: The effect of different preservation methods or phenolic additives during chilled and frozen storage of meat/meat products

Lipid and protein oxidation have significant effects on the shelf-life and nutritional value of meat and meat products. While lipid oxidation has been extensively studied, it has been recognized that proteins are also susceptible to oxidation. However, the precise mechanisms of oxygen-induced amino acid and protein modifications in the food matrix remain unclear. This review comprehensively explores the impact of various preservation techniques, including high hydrostatic pressure (HHP), irradiation (IR), and modified atmosphere packaging (MAP), on protein oxidation during chilled or frozen storage of meat products. While these techniques have shown promising results in extending shelf-life, their effects on protein oxidation are dose-dependent and must be carefully controlled to maintain product quality. Preservation techniques involving the use of phenolic additives have demonstrated synergistic effects in mitigating protein oxidation during storage. Notably, natural phenolic additives have shown comparable efficacy compared to artificial antioxidants. Additionally, incorporating phenolic additives into bio-edible films has shown promise in combating protein oxidation.

Effect of portulaca (Portulaca oleracea L.) extract on the quality and physicochemical attributes of vacuum-packed seasoned steaks during chilled storage

BACKGROUND

Vacuum packaging has the ability to reduce oxidative deterioration and microbial-induced spoilage of meat. However, in an oxygen-free environment, it can lead to the development of an unappealing purplish-red color and a decrease in the water-holding capacity of meat, thereby impacting the overall meat quality. Portulaca oleracea L. (POL) is a homology of medicine and food known for its exceptional antioxidant and antimicrobial properties.

RESULTS

The aim of our present study was to investigate the antioxidant and antimicrobial ability of n-butanol phase extract of POL and the effect of POL extract incorporation on the quality (water-holding capacity, shear force, color, and texture) and physicochemical (pH, total volatile base nitrogen, and total viable counts) attributes of vacuum-packed seasoned steaks at 4 °C over a 15-day period. Results showed that the POL extract had excellent antioxidant and antimicrobial capacity. Furthermore, the addition of POL extract significantly inhibited protein oxidation and microbial growth of steaks (P < 0.05), and improved the water-holding capacity, color properties, and tenderness (P < 0.05). Moreover, there were no significant differences (P > 0.05) in the color, water-holding capacity, or tenderness between the 0.5 and 1 g kg-1 POL extract treatment groups compared to the sodium nitrite control group.

CONCLUSION

These results indicate that POL extract had the potential to replace sodium nitrite due to its ability to hinder protein oxidation and microbial growth of vacuum-packed seasoned steaks, while enhancing the color, water-holding capacity, and tenderness of seasoned steaks. © 2024 Society of Chemical Industry.

The effect of common duckweed (Lemna minor L.) extract on the shelf-life of beef burgers stored in modified atmosphere packs: A metabolomics approach

The impact of duckweed extracts (DEs) on the shelf-life of packaged beef burgers was evaluated through classical assays and untargeted metabolomics. Beef burgers were formulated with an antioxidants-free control (CON), 1 g/kg sodium ascorbate (ASC), and increasing levels of a DEs, namely 1 (DE1), 5 (DE5), and 10 (DE10) g/kg, packaged under modified atmosphere and stored at 4 °C for 19 days. The DEs, abundant in phytochemicals, determined no issues with the hygienic status of the product. DEs modulated the redox status, being ineffective in preserving linolenic acid from peroxidation. However, the oxidation marker 2-nonenoic acid was down-accumulated in the DE10 sample following 19 days of storage, recording a lower glutathione:glutathione disulfide ratio. The accumulation of adipate semialdehyde revealed the inefficiency of DEs in coping with protein oxidation, while DEs prevented the accumulation of biogenic amines. Therefore, this work suggests a potential pro-oxidant role of the formulated DEs.

Elderberry Lipophilic and Hydrophilic Bioactive Compounds: Characterization and Extract Encapsulation

There are few studies on the use of elderberry in the food industry, and its form of application differs between the different studies. Therefore, the objective of this study is to describe a procedure for obtaining a stabilized product with a high content of hydrophilic bioactive compounds (encapsulated elderberry extract). Moreover, the solid residue resulting from the extraction of the polyphenols was characterized, and the lipophilic compounds retained in this residue were analyzed. The results show an important antioxidant activity of the extracts obtained, mainly linked to the high content of anthocyanins, hydroxycinnamic acids, and flavonols. The lipophilic bioactive compounds were characterized by a high content of essential fatty acids and high proportions of tocopherols. The information and results of the present study provide novel information about both lipophilic and hydrophilic compounds for the integral valorization of elderberries to promote a circular economy strategy.

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.

Optimization of Major Extraction Variables to Improve Recovery of Anthocyanins from Elderberry by Response Surface Methodology

Elderberry, which is well known for its richness in anthocyanin, is attracting attention in the bioindustry as a functional material with high antioxidant capacity. The aim of this study is to optimize extraction conditions to more effectively recover anthocyanins from elderberry. In a fundamental experiment to determine the suitable solvent, various GRAS reagents, such as acetone, ethanol, ethyl acetate, hexane, and isopropyl alcohol, were used, and total phenol and anthocyanin contents were detected as 9.0 mg/g-biomass and 5.1 mg/g-biomass, respectively, only in the extraction using ethanol. Therefore, ethanol was selected as the extraction solvent, and an experimental design was performed to derive a response surface model with temperature, time, and EtOH concentration as the main variables. The optimal conditions for maximal anthocyanin recovery were determined to be 20.0 °C, 15.0 min, and 40.9% ethanol, and the total anthocyanin content was 21.0 mg/g-biomass. In addition, the total phenol and flavonoid contents were detected as 67.4 mg/g-biomass and 43.8 mg/g-biomass, respectively. The very simple and economical extraction conditions suggested in this study contributed to improving the utilization potential of anthocyanin, a useful antioxidant derived from elderberry.