Exploring the Untapped Potential of Pine Nut Skin By-Products: A Holistic Characterization and Recycling Approach.

The increasing population, food demand, waste management concerns, and the search for sustainable alternatives to plastic polymers have led researchers to explore the potential of waste materials. This study focused on a waste of pine nut processing referred to in this paper as pine nut skin. For the first time, its nutritional profile, potential bioactive peptide, contaminants, and morphological structure were assessed. Pine nut skin was composed mainly of carbohydrates (56.2%) and fiber (27.5%). The fat (9.8%) was about 45%, 35%, and 20% saturated, monounsaturated, and polyunsaturated fatty acid, respectively, and Omega-9,-6, and -3 were detected. Notably, oleic acid, known for its health benefits, was found in significant quantities, resembling its presence in pine nut oil. The presence of bioactive compounds such as eicosapentaenoic acid (EPA) and phytosterols further adds to its nutritional value. Some essential elements were reported, whereas most of the contaminants such as heavy metals, polycyclic aromatic hydrocarbons, rare earth elements, and pesticides were below the limit of quantification. Furthermore, the in silico analysis showed the occurrence of potential precursor peptides of bioactive compounds, indicating health-promoting attributes. Lastly, the morphological structural characterization of the pine nut skin was followed by Fourier Transform Infrared and solid-state NMR spectroscopy to identify the major components, such as lignin, cellulose, and hemicellulose. The thermostability of the pine nut skin was monitored via thermogravimetric analysis, and the surface of the integument was analyzed via scanning electron microscopy and volumetric nitrogen adsorption. This information provides a more comprehensive view of the potential uses of pine nut skin as a filler material for biocomposite materials. A full characterization of the by-products of the food chain is essential for their more appropriate reuse.

Bile salts enhance the susceptibility of the peach allergenic lipid transfer protein, Pru p 3, to in vitro gastrointestinal proteolysis.

Sensitisation to the lipid transfer protein Pru p 3 is associated with severe allergic reactions to peach, the proteins stability being thought to play a role in its allergenicity. Lipid binding increases susceptibility of Pru p 3 to digestion and so the impact of bile salts on the in vitro gastrointestinal digestibility of Pru p 3 was investigated and digestion products mapped by SDS-PAGE and mass spectrometry. Bile salts enhanced the digestibility of Pru p 3 resulting in an ensemble of around 100 peptides spanning the protein's sequence which were linked by disulphide bonds into structures of ~ 5-6 kDa. IgE binding studies with a serum panel from peach allergic subjects showed digestion reduced, but did not abolish, the IgE reactivity of Pru p 3. These data show the importance of including bile salts in vitro digestion systems and emphasise the need to profile of digestion in a manner that allows identification of immunologically relevant disulphide-linked peptide aggregates.

Identification of allergen encoding sequences in a novel food ingredient from Moringa oleifera leaves.

Alternative sources of edible proteins are required to feed the world's growing population, such as Moringa oleifera leaves, a protein source with a balanced amino acid composition. Since Moringa leaf proteins is a novel food in the EU and UK, an assessment of their potential allergenicity of is required. Proteins from Moringa leaf powder were characterised using traditional proteomic approaches. The proteins identified were evaluated for their allergenic potential using in-silico tools. The main proteins identified belonged to photosynthetic and metabolic pathways. In-silico analysis of the leaf proteome identified moritides as potential allergens by homology with a latex allergen implicated in fruit-latex syndrome. This analysis also identified a nsLTP, a major panallergen in food. The presence of these putative allergens was confirmed by de-novo sequencing. Our study allowed identification of putative allergens, Morintides and nsLTP. Further in-vitro and in-vivo investigations are required to confirm their allergenic potential.

Polydatin Incorporated in Polycaprolactone Nanofibers Improves Osteogenic Differentiation.

Polycaprolactone nanofibers are used as scaffolds in the field of tissue engineering for tissue regeneration or drug delivery. Polycaprolactone (PCL) is a biodegradable hydrophobic polyester used to obtain implantable nanostructures, which are clinically applicable due to their biological safety. Polydatin (PD), a glycosidic precursor of resveratrol, is known for its antioxidant, antitumor, antiosteoporotic, and bone regeneration activities. We aimed to use the osteogenic capacity of polydatin to create a biomimetic innovative and patented scaffold consisting of PCL-PD for bone tissue engineering. Both osteosarcoma cells (Saos-2) and mesenchymal stem cells (MSCs) were used to test the in vitro cytocompatibility of the PD-PCL scaffold. Reverse-phase (RP) HPLC was used to evaluate the timing release of PD from the PCL-PD nanofibers and the MTT assay, scanning electron microscopy, and alkaline phosphatase (ALP) activity were used to evaluate the proliferation, adhesion, and cellular differentiation in both osteosarcoma and human mesenchymal stem cells (MSCs) seeded on PD-PCL nanofibers. The proliferation of osteosarcoma cells (Saos-2) on the PD-PCL scaffold decreased when compared to cells grown on PLC nanofibers, whereas the proliferation of MSCs was comparable in both PCL and PD-PCL nanofibers. Noteworthy, after 14 days, the ALP activity was higher in both Saos-2 cells and MSCs cultivated on PD-PCL than on empty scaffolds. Moreover, the same cells showed a spindle-shaped morphology after 14 days when grown on PD-PCL as shown by SEM. In conclusion, we provide evidence that nanofibers appropriately coated with PD support the adhesion and promote the osteogenic differentiation of both human osteosarcoma cells and MSCs.

Casein-derived peptides from the dairy product kashk exhibit wound healing properties and antibacterial activity against Staphylococcus aureus: Structural and functional characterization.

Kashk is a fermented dairy product typical of the Middle East, traditionally produced with sour milk and/or dairy waste. The kashk water-soluble peptide fraction was characterized at the molecular level by liquid chromatography-mass spectrometry and its antibacterial and skin healing activity was evaluated. Antibacterial assays showed a significant antibacterial activity against clinical isolates of Staphylococcus aureus (S. aureus) from patients with atopic dermatitis, inhibiting bacterial growth by approximately 45% (500 µg/mL). Skin repair activity was evaluated on keratinocytes through scratch tests showing accelerated wound closure in vitro in the presence of TNF-α, by approximately 44% (500 µg/mL), compared to control cells. Furthermore, based on the MTT assay, the kashk peptide fraction did not show toxicity on keratinocytes. The results suggested that the peptide kashk extract may be useful in skin care for patients with atopic dermatitis.

Tritordeum as an Innovative Alternative to Wheat: A Comparative Digestion Study on Bread.

Tritordeum results from the crossbreeding of a wild barley (Hordeum chilense) species with durum wheat (Triticum turgidum spp. turgidum). This hexaploid crop exhibits agronomic and rheological characteristics like soft wheat, resulting in an innovative raw material to produce baked goods. We applied a gel-based proteomic approach on refined flours to evaluate protein expression differences among two widespread tritordeum cultivars (Aucan and Bulel) taking as the reference semolina and flour derived from a durum and a soft wheat cvs, respectively. The products of in vitro digestion of model breads were analyzed to compare bio-accessibility of nutrients and mapping tritordeum bread resistant peptides. Significant differences among the protein profiles of the four flours were highlighted by electrophoresis. The amino acid bio-accessibility and the reducing sugars of tritordeum and wheat breads were comparable. Tritordeum cvs had about 15% higher alpha-amino nitrogen released at the end of the duodenal simulated digestion than soft wheat (p < 0.05). Bulel tritordeum flour, bread and digested bread had about 55% less R5-epitopes compared to the soft wheat. Differences in protein expression found between the two tritordeum cvs reflected in diverse digestion products and allergenic and celiacogenic potential of the duodenal peptides. Proteomic studies of a larger number of tritordeum cvs may be successful in selecting those with good agronomical performances and nutritional advantages.

The effect of nitrogen fertilization on the expression of protein in wheat and tritordeum varieties using a proteomic approach.

Wheat, an essential ingredient for several bakery preparations, is also responsible for gluten-related diseases in sensitive subjects. The effect of the N fertilization rate (80 vs 160 kg N ha-1) on gluten protein expression profile has been evaluated considering two soft wheats (landrace and modern) and one tritordeum cultivar (cv), grown in the same experimental field in North Italy. The proteins of refined flour were characterized through advanced proteomic approaches, including chromatography (RP-HPLC) and electrophoresis. A static model system was used to simulate in vitro digestion and the digestome peptides were examined by mass spectrometry and in silico approaches, to investigate the celiac and allergenic sequences. The CD-toxic epitopes in the digested samples were quantified by means of a R5 ELISA assay. The N fertilization rate increased the grain protein content, but it did not lead to any difference in gluten composition, with exception of glu/glia ratio in the modern wheat cv. Moreover, the gluten composition and the occurrence of toxic/allergenic epitopes varied to a great extent, according mostly to the genotype. A lower immunoreactivity, determined using R5 ELISA, was detected for the digested tritordeum flours than for the landrace (-51%) or modern (-58%) cvs, while no significant difference was observed for the N rates between each genotype. In silico analysis showed that tritordeum has fewer CD epitopes belonging to the ω-gliadins and a lower LMW-GS than the landrace or modern cv. Tritordeum presented fewer α-gliadin allergenic epitopes than the modern wheat cv. The lower frequency of celiac epitopes in tritordeum, compared to the old and the modern wheat, is probably due to the absence of a D genome.

The protein and peptide fractions of kashk, a traditional Middle East fermented dairy product.

Kashk is a typical dairy product of Iran, made from sour milk. It is traditionally produced from buttermilk in a dry, round-shaped form. Today, it is also produced at industrial level in a liquid form starting from fermented milk. We aimed to characterise the kashk proteome and peptidome comparing a traditional product with the industrial using a combination of proteomic approaches including advanced chromatographic and electrophoretic separation technique coupled to tandem mass spectrometry. We identified also phosphorylated casein-derived peptides (CPP) and investigated kashk protein digestibility using a static model of food protein digestion. The molecular characterization, coupled with bioinformatic in silico analysis, allowed the identification of potential bioactive peptides.