Whey represents the major by-product of cheese industry. One possibility to recycle the whey wastes is the use of their globular proteins as a polymer source for the production of biodegradable plastic materials. Whey protein (WP)-based films are usually obtained by protein heat treatment in the presence of glycerol (GLY) as plasticizer at pH 7, a method which would require commercially high costing process. In this work we explored the possibility of producing manageable whey-derived materials without any heat-treatment but under alkaline conditions. The reported results demonstrated that the casting at pH 12 of the unheated WP film forming solutions (FFSs), containing either 40% or 50% GLY, led to produce more resistant and flexible materials than the ones obtained at pH 7. Film opacity was observed significantly increased, being higher in the samples obtained at alkaline pH without WP heating and with higher GLY concentrations. Finally, moisture content decreased with the reduction of GLY content, both in heated and unheated WP-based films, whereas water uptake of the different films prepared at pH 12 did not significantly change.

Polyphenols are widely studied phytochemicals with well-known antioxidant and anti-inflammatory properties. They are commonly present in fruits, vegetables, and plant-based foods. Beyond these classical roles, growing evidence shows that polyphenol-derived bioactive metabolites—produced or modified by the gut microbiota—can promote host health. These metabolites are increasingly recognized for shaping host–microbe interactions and influencing neurophysiological functions via the gut–brain axis. This review provides an overview of polyphenol transformation rates by the gut microbiome, highlighting their microbial transformation, anti-biofilm effects, and neuroprotective potential. In our opinion, a deeper understanding of the properties of these metabolites can significantly impact food science and biotechnology.

Background: Flowering members of the globally diffused Rosaceae family include popular plants, such as apple, almond, and cherry, which play a fundamental role as honeybee nectariferous and polleniferous agents. Through the production of honey, these plants can also play an indirect role in the prevention and treatment of many diseases, including infections, fighting the occurrence of resistant microorganisms, and concurrently stimulating the growth of beneficial bacteria. Objectives: This study focused on the effect of some Rosaceae plants’ honey, including hawthorn, cherry, raspberry, almond, and apple, against the pathogens Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Pseudomonas aeruginosa, and Staphylococcus aureus. Results: Results demonstrated the honey’s ability to impair swimming motility. A crystal violet test indicated that honey could inhibit the formation and stabilization of biofilms, with inhibition rates up to 59.43% for immature biofilms (showed by apple honey against A. baumannii) and 39.95% for sessile bacterial cells in mature biofilms (when we used cherry honey against S. aureus). In the test with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, cherry and apple honey were the most effective in inhibiting sessile cell metabolism honey in both immature (56.47% cherry honey vs. K. pneumoniae) and mature biofilms (54.36% apple honey vs. A. baumannii). Honey stimulated the growth of Lactobacillus bulgaricus, Lacticaseibacillus casei Shirota, Lactobacillus gasseri, Lacticaseibacillus plantarum, and Lacticaseibacillus rhamnosus; hawthorn, raspberry, and almond honey significantly increased the in vitro adhesion capacity of L. bulgaricus and L. casei Shirota. Tests with probiotic supernatants demonstrated honey’s ability to inhibit the biofilm formation and metabolism of the pathogens. Conclusions: Our results encourage further studies to assess the potential application of Rosaceae honey for food preservation and in the health field, as it could fight the antimicrobial resistance of food and clinical pathogens, and potentially enhance the host’s gut wellness. The use of honey for nanotechnological and biotechnological approaches could be suggested too.

The present study aimed to produce bio-active packaging materials made of whey proteins (WPs) and essential oil (EO) extracted from Thymbra (Satureja capitata, L.), one of the most popular Palestinian wild plants. In this study, two different Thymbra leaves from Nablus and Qabatiya in Palestine were collected and analyzed for EOs by gas chromatography and mass spectrometry. Based on the analysis, two EOs, namely, TEO1 and TEO2, were extracted, and it was found that both samples primarily contain γ-terpinene and carvacrol, whereas p-cymene was detected only in TEO1. The antimicrobial activity of TEO1 and TEO2 was evaluated by microbroth microdilution assays against pathogenic bacteria and yeast. Based on the results, TEO1 exhibited potent antimicrobial activity against the test strains. Besides, TEO1 was chosen to functionalize WP-based films at different concentrations (0.1%, 0.4%, and 0.8% v/v of Film Forming Solutions). Film mechanical property investigation showed a marked reduction in the tensile strength and Young’s modulus at 0.8% TEO1. In contrast, its elongation at break value was significantly (p < 0.05) increased due to the plasticizing effect of the EO. Moreover, the film transparency was found to be significantly (p < 0.05) reduced by increasing TEO1 concentrations. Finally, microbiological investigations indicated that film antimicrobial activity against both gram-positive and gram-negative bacteria increased dose-dependently. The overall results open interesting perspectives for employing these films as preservative materials in food packaging.

This study sheds light on the potential of microbial transglutaminase (mTG)-mediated modification to enhance the properties of heat-denatured whey protein-based films. In this study, we investigated the biochemical modification of heat-denatured whey proteins (WPs) using mTG, an enzyme known for the ability of crosslinking reactions. By introducing ε-(γ-glutamyl)-lysine crosslinks via an acyl transfer reaction, mTG enhances the properties of bio-based materials. In this research, heated WPs were demonstrated to effectively serve as mTG substrates. The preparation of crosslinked bio-based material was achieved using a casting method under alkaline conditions (pH 12) in the presence of glycerol (40% w/w), which was added as a plasticizer to the film-forming solution (FFS). A comprehensive characterization of the FFSs and the resulting materials was carried out. The FFSs were quite stable as evidenced by Zeta potential values that were always around 30/40 mV regardless of the presence of the enzyme. The enzymatic modification increased the elongation at break of the materials from 10.4 ± 4.9 MPa to 27.6 ± 8.9 MPa, while decreasing both tensile strength and Young’s modulus, thereby making the resulting material more extensible. On the other hand, the enzyme affected both the CO₂ and O₂ barrier properties, with permeability values for these gases being 0.90 cm³ mm m⁻² day⁻¹ kPa⁻ and 0.26 cm³ mm m⁻² day⁻¹ kPa, respectively, when the films were cast without the enzymatic treatment, but decreasing to 0.14 ± 0.02 cm³ mm m⁻² day⁻¹ kPa (CO₂) and 0.02 ± 0.02 cm³ mm m⁻² day⁻¹ kPa (O₂) in the presence of 24 U/g of mTG. These novel materials, prepared from renewable sources, could potentially be used in the food packaging field to replace/reduce the highly pollutant petroleum-based ones.

Milk whey (MW) represents the major by-product of cheese industry. One possibility to recycle the MW wastes is the use of their globular proteins (MWPs) as a polymer source for the production of biodegradable plastic materials. MWP-based films are usually obtained by protein heat treatment in the presence of glycerol (GLY) as plasticizer at pH 7, a method which would require commercially high costing process. In this work it was exploited the possibility to produce manageable MW-derived biomaterials without any heat-treatment but under alkaline conditions. Our results demonstrated that the casting at pH 12 of the unheated MWP film forming solutions (FFSs), containing either 40% or 50% GLY, led to produce more resistant and flexible biomaterials than the ones obtained at pH 7. Also film transparency was observed significantly improved, being lower in the samples obtained at alkaline pH without MWP heating and with higher GLY concentrations. Finally, moisture content decreased with the reduction of GLY content, both in heated and unheated MWP-based films, whereas water uptake of the different films prepared at pH 12 did not significantly change.