Spirulina Phycobiliproteins as Food Components and Complements

Spirulina has a documented history of use as a food for more than 1000 years, and has been in production as a dietary supplement for 40 years. Among many of Spirulina bioactive components, blue protein C-phycocyanin and its linear tetrapyrrole chromophore phycocyanobilin occupy a special place due to broad possibilities for application in various areas of food technology. The subject of this chapter is up-to-date food applications of these Spirulina components, with a focus on their use as food colorants, additives, nutriceuticals, and dietary supplements. Their other actual and future food application possibilities will also be briefly presented and discussed

Molecular Mechanisms of Possible Action of Phenolic Compounds in COVID-19 Protection and Prevention

The worldwide outbreak of COVID-19 was caused by a pathogenic virus called Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Therapies against SARS-CoV-2 target the virus or human cells or the immune system. However, therapies based on specific antibodies, such as vaccines and monoclonal antibodies, may become inefficient enough when the virus changes its antigenicity due to mutations. Polyphenols are the major class of bioactive compounds in nature, exerting diverse health effects based on their direct antioxidant activity and their effects in the modulation of intracellular signaling. There are currently numerous clinical trials investigating the effects of polyphenols in prophylaxis and the treatment of COVID-19, from symptomatic, via moderate and severe COVID-19 treatment, to anti-fibrotic treatment in discharged COVID-19 patients. Antiviral activities of polyphenols and their impact on immune system modulation could serve as a solid basis for developing polyphenol-based natural approaches for preventing and treating COVID-19

The modifications of bovine β-lactoglobulin: Effects on its structural and functional properties

Due to its excellent techno-functional properties, high nutritional value and low cost, beta-lactoglobulin (BLG), the main protein in whey, is a frequently used additive in wide range of food products. It is also considered as an acid-resistant drug carrier for the delivery of pharmaceutical and nutraceutical agents. However, BLG is the main allergen of milk. A variety of methods has been explored for the modification of BLG in attempts to improve its functional properties and to decrease its allergenicity. Due to its compact globular structure, BLG is relatively resistant to modifications, especially under, mild conditions. BLG can be modified by physical, chemical and enzymatic treatments. Although chemical modifications offer efficient routes to the alteration of the structural and functional properties of proteins, they are associated with safety concerns. In the last decade, there is a tendency for application of novel non-thermal physical processing methods, as well as enzymes in order to obtain BLG derivatives with desirable properties. The objective of this review is to overview the chemical, physical and enzymatic processing techniques utilized to modify BLG and their effects on the structural and functional properties of BLG.Beta-laktoglobulin (BLG) je glavni protein surutke koji se često koristi kao aditiv u velikom broju prehrambenih proizvoda zahvaljujući svojim izvanrednim tehničkim i funkcionalnim osobinama, visokoj nutritivnoj vrednosti, kao i niskoj ceni. Ovaj protein se pokazao kao pogodan nosač za lekove i hranljive supstance, jer je otporan na kiselu sredinu u gastro-intestinalnom traktu. Međutim, BLG je i glavni alergen mleka. Sa ciljem unapređenja funkcionalnih osobina i smanjenja alergenosti ovog proteina do sada je razvijen veliki broj metoda za njegovu modifikaciju. Zahvaljujući svojoj kompaktnoj globularnoj strukturi BLG je relativno rezistentan na modifikacije, naročito one pod blagim uslovima. BLG može biti modifikovan fizičkim, hemijskim i enzimskim metodama. Mada su hemijske modifikacije efikasan način promene strukturnih i funkcionalnih osobina proteina, u vezi sa njima se često postavlja pitanje bezbednosti. Tokom poslednje decenije postoji sve veća tendencija ka primeni novih tretmana zasnovanih na fizičkim netermalnim metodama, kao i na primeni enzima, kako bi se dobio BLG sa željenim osobinama. Cilj ovog preglednog rada je prikaz hemijskih, fizičkih i enzimskih tehnika koje se koriste za modifikaciju BLG, kao i njihovih efekata na strukturu i funkciju BLG

The role of dietary phenolic compounds in protein digestion and processing technologies to improve their antinutritive properties

Digestion is the key step for delivering nutrients and bioactive substances to the body. The way different food components interact with each other and with digestive enzymes can modify the digestion process and affect human health. Understanding how food components interact during digestion is essential for the rational design of functional food products. Plant polyphenols have gained much attention for the bioactive roles they play in the human body. However, their strong beneficial effects on human health have also been associated with a negative impact on the digestion process. Due to the generally low absorption of phenolic compounds after food intake, most of the consumed polyphenols remain in the gastrointestinal tract, where they then can exert inhibitory effects on enzymes involved in the degradation of saccharides, lipids, and proteins. While the inhibitory effects of phenolics on the digestion of energy-rich food components (saccharides and lipids) may be regarded as beneficial, primarily in weight-control diets, their inhibitory effects on the digestion of proteins are not desirable for the reason of reduced utilization of amino acids. The effect of polyphenols on protein digestion is reviewed in this article, with an emphasis on food processing methods to improve the antinutritive properties of polyphenols

Digestion by pepsin releases biologically active chromopeptides from C-phycocyanin, a blue-colored biliprotein of microalga Spirulina

C-phycocyanin, the major protein of cyanobacteria Spirulina, possesses significant antioxidant, anti-cancer, anti-inflammatory and immunomodulatory effects, ascribed to covalently attached linear tetrapyrrole chromophore phycocyanobilin. There are no literature data about structure and biological activities of released peptides with bound chromophore in C-phycocyanin digest. This study aims to identify chromopeptides obtained after pepsin digestion of C-phycocyanin and to examine their bioactivities. C-phycocyanin is rapidly digested by pepsin in simulated gastric fluid. The structure of released chromopeptides was analyzed by high resolution tandem mass spectrometry and peptides varying in size from 2 to 13 amino acid residues were identified in both subunits of C-phycocyanin. Following separation by HPLC, chromopeptides were analyzed for potential bioactivities. It was shown that all five chromopeptide fractions have significant antioxidant and metal-chelating activities and show cytotoxic effect on human cervical adenocarcinoma and epithelial colonic cancer cell lines. In addition, chromopeptides protect human erythrocytes from free radical-induced hemolysis in antioxidative capacity dependant manner. There was a positive correlation between antioxidative potency and other biological activities of chromopeptides. Digestion by pepsin releases biologically active chromopeptides from C-phycocyanin whose activity is mostly related to the antioxidative potency provided by chromophore. (C) 2016 Elsevier B.V. All rights reserved.Peer-reviewed manuscript: [http://cherry.chem.bg.ac.rs/handle/123456789/3444]Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3445

Glycation of the Major Milk Allergen β-Lactoglobulin Changes its Allergenicity by Alterations in Cellular Uptake and Degradation

SCOPE: During food processing the Maillard reaction (МR) may occur resulting in the formation of glycated proteins. Glycated proteins are of particular importance in food allergy since glycation may influence interactions with immune system. This study compared native and extensively glycated milk allergen β-lactoglobulin (BLG), in their interactions with cells crucially involved in allergy. METHODS AND RESULTS: BLG was glycated in MR and characterized. Native and glycated BLG were tested in experiments of epithelial transport, uptake and degradation by DCs, T-cell cytokine responses and basophil cell degranulation using ELISA and flow cytometry. Glycation of BLG induced partial unfolding and reduced its intestinal epithelial transfer over a Caco-2 monolayer. Uptake of glycated BLG by bone marrow-derived dendritic cells (BMDC) was increased, although both BLG forms entered BMDC via the same mechanism, receptor-mediated endocytosis. Once inside the BMDC, glycated BLG was degraded faster, which might have led to observed lower cytokine production in BMDC/CD4+ T-cells coculture. Finally, glycated BLG was less efficient in induction of degranulation of BLG-specific IgE sensitized basophil cells. CONCLUSIONS: This study suggests that glycation of BLG by MR significantly alters its fate in processes involved in immunogenicity and allergenicity, pointing out the importance of food processing in food allergy. This article is protected by copyright. All rights reserved

Noncovalent interactions of bovine α-lactalbumin with green tea polyphenol, epigalocatechin-3-gallate

Bovine alpha-lactalbumin (ALA) is an important Ca-binding protein of milk. Epigallocatechin-3-gallate (EGCG) is the major and the most biologically active catechin of green tea, which has the highest binding affinity to whey proteins due to galloyl functional group. In this study experimental and computational methods were used to investigate noncovalent interactions of EGCG and ALA. Binding affinity of EGCG for ALA, determined by fluorescence quenching analysis, was in the range described for complexes of EGCG and other dietary proteins, and lower than affinity of some phenolic compounds to ALA. Based on circular dichroism and Fourier transform infrared spectroscopy spectra, binding of EGCG change ALA conformation inducing alpha-helix to beta-structures transition. The isothermal titration calorimetry results suggest that the binding of EGCG to ALA is enthalpically favorable. The docking analysis shows that EGCG binds in the hydrophobic pocket at the entrance of cleft between alpha-helical and beta-sheetrich domains and includes residues of aromatic cluster II. Uptake of ALA by monocytes proceeds at a slower rate in the presence of EGCG suggesting that EGCG binding may impair uptake of ALA by antigen-presenting cells. ALA, being of low cost and widely available protein, can serve as suitable delivery system for EGCG, as well as for food fortification with this bioactive catechin. (C) 2016 Elsevier Ltd. All rights reserved.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3585

(A) Temperature dependence of 0.5 μM HSA ellipticity at 222 nm in the presence and absence of 0.5 μM PCB; (B) Temperature dependence of 1 μM HSA fluorescence at 340 nm in the presence and absence of 1 μM PCB (λ_EX = 280 nm); (C) SDS-PAGE profile after trypsin digestion of 3.8 μM HSA in the presence and absence of 3.8 μM PCB.

<p>Lane K: HSA without trypsin; lane M: MW markers; lanes 1–6 correspond to digestion times 0.5, 2, 5, 10, 30, and 60 min without PCB, respectively; lanes 7–12 correspond to digestion times 0.5, 2, 5, 10, 30 and 60 min with PCB, respectively.</p

Catalogue Maison Bigot [titres “Viens dans ma nacelle” => “Bazeilles”]

Catalogue Maison Bigot, 157 rue du Temple [Paris] : “Romances et chansons nouvelles” (verso “Sommes nous prêts ?”) ; titres : “Viens dans ma nacelle => “Bazeilles” ; quatre colonnes par deux foix (titres, auteurs, compositeurs, genres) ; interprètes crédités dans la colonne “genre” : Marius Richard, Mercadier, Amiati, Debailleul, Paulus, B. Delahaye, Gibert, Garnier [Léon Garnier], d’Aubreuil [Daubreuil ?], Antony [Antony Lassaigne], Duhem [Émile Duhem], Canon [Fernande Canon], Bourgès, Bonnet, E. Faure [Elise Faure], Dlle (Mlle?) Derly, Libert, Caudieux, Leduc, Judith, G. Lange [Gabrielle Lange], Mme Barnoll, Kaiser [Augustine Kaïser], Limat [Louis Limat], Farville, Réval [Jules Réval], Velly [Louis Velly], Plessis [Henri Plessis] ; datation par analyse des titres 1886 (hypothèse à confirmer)

Calculated RMSF values (Å) from molecular dynamics simulation of free HSA, HSA-PCB(IB), and HSA-PCB(IIA).

<p>RMSF values along whole protein sequence (A), sum of RMSF values of each HSA domain (B), and difference of RMSF values between PCB-HSA complexes and free HSA, with marked amino acid (aa) residues involved in PCB binding for site IB (C), and for site IIA (D).</p