Stability of the Meat protein type I collagen: Influence of pH, ionic strength, and phenolic antioxidant

The water-holding capacity (WHC) is among the key factors in determining the quality of meat and its value, which is strongly influenced by the content and quality of the connective tissue proteins like collagen. Therefore, the factors that influence the proteins' stability, e.g., pH, ionic strength, and the antioxidants which are used to increase the meat shelf-life, also affect the WHC. The interaction of collagen, whose structure is strongly influenced by the interaction with water molecules, can be studied following the behavior of water diffusion by low-resolution 1H NMR experiments. The present study is addressed to study the collagen stability as a function of pH, ionic strength, and phenolic antioxidants like catechin. The experimental study demonstrated how the 1H NMR time domain (TD) experiments are able to evaluate the hydration properties of collagen, not only as a function of ionic strength and pH, but also in determining the ability of catechin to interact both on the surface of the collagen fibrils and inside the fibrillar domain

Mantonico and Pecorello Grape Seed Extracts: Chemical Characterization and Evaluation of In Vitro Wound-Healing and Anti-Inflammatory Activities

The winemaking process produces a huge number of pomaces that generally are used for energy purposes. Further valuable applications such as health-promoting properties are still under investigation. The seeds of the white berries of Mantonico and Pecorello cv. were extracted in a Soxhlet apparatus, using n-hexane and chloroform as solvents. Extracts were characterized by NMR and GC-MS analyses. They were assayed in vitro as wound healing and anti-inflammatory agents in HaCaT and RAW 264.7 cell lines, respectively. n-hexane Mantonico extract resulted in the most interesting wound healing sample, while n-hexane Pecorello, containing a good number of carotenoids, resulted in a good anti-inflammatory candidate. These preliminary findings underlined the benefit of grape seed extracts valorization due to their health-promoting propertie

Sangiovese cv Pomace seeds extract-fortified Kefir exerts anti-inflammatory activity in an in vitro model of intestinal epithelium using Caco-2 cells

Inflammatory bowel disease and food allergies are a growing topic in the field of nutrition science. Polyphenols, which are the most important secondary metabolites of plants, demonstrated to modulate the expression and/or production of numerous proteins, but also to regulate the intestinal ecosystem. In this context, our aim was the investigation of protective effects against the gastrointestinal mucosa of fortified milk kefir obtained by adding seeds extract from Sangiovese cv. Pomace. Methods: An ultrasound-assisted method was used to obtain the extracts. All the extracts were assayed for the antioxidant activity. The best extract was used as an additive of fermented milk kefir to obtain a fortified final product. Kefir samples were analyzed by NMR spectroscopy. The efficiency of the barrier functions was evaluated by measuring trans-epithelial electric resistance (TEER) using a voltmeter. Results: the enriched kefir (Ksgn) possesses higher antioxidant performances compared to the unfortified sample (Kwht). Kwht and Ksgn did not alter Caco-2 TEER in basal condition

quality of commercial flavoured oils and seed oils using a widespread analytical protocol

Commercial flavoured olive and olive-sunflower oils and seed oils with particular nutritional properties (e.g. linseed, safflower, sunflower, sesame and rice oils) were analysed using a widespread analytical protocol to have information on their quality and chemical composition. The protocol involved traditional determinations (free acidity, peroxide value, UV and VIS spectrophotometric indices, and fatty acid composition) along with 1H and 13C NMR analyses. Most of flavoured olive oils turned out to be lampante olive oils and not extra virgin as declared in the label on the bottle. In the case of olive-sunflower oils only a minor fraction of olive oil was revealed although these products are particularly expensive and the presence of olive oil is emphasized on the label. In some seed oils, refinement processes, not indicated on the bottle, were highlighted. Some compounds characteristic of specific seed oils were identified in the 1H spectra.</p

Nuclear Magnetic Resonance spectroscopy. In vivo determination of pH; cations and metabolites

In this paper we report on some recent applications that represent remarkable progress in the study of in vivo biochemical and biophysical processes, with particular attention for the determination of pH, Mg2+ and metabolite concentration

H-1 NMR studies of alginate interactions with amino acids

The interactions between alginate and the amino acids,histidine, lysine,phenylalanine, and alanine,were studied by Proton Nuclear Magnetic Resonance. The characterization of the amino acids interaction with alginate was performed by 1D and 2D-NOESY experiments. Measurements of 1HNMR nonselective and selective relaxation rates in the absence and presence of alginate were used to calculate interaction constants between each amino acid and alginate. The interaction constants were found to be related to the hydrophobicity of the different amino acid side-chains. The interaction constant between phenylalanine and Ca2þ crosslinked alginate was also determined. There was no apparent differences observed in the crosslinked and the solution amino acid–alginate interactions. On the basis of the experimental results obtained,a mode