Although the impact of oxidation on human health has been of growing interest, the oxidation of proteins, major component of meat, has received little attention. This paper describes the in vitro effect of five fluoroquinolones (FQs) on carbonylation of sarcoplasmic and myofibrillar proteins of beef when found at concentrations close to the maximum residue limit (MRL). Samples were treated individually with the FQs, determining in each protein fraction the carbonyl index, protein content and oxidized proteins identification, using 2,4-dinitrophenyhydrazine (DNPH) alkaline assay, Western blot and Bradford methods, and mass spectrometry, respectively. Besides, the in vitro effect of these residues on gastric and duodenal digestion of proteins was evaluated. The carbonylation induced by FQs affected both protein fractions being significant with respect to the blank in 73.3% of cases. This damage was correlated with loss of solubility and digestibility, with sarcoplasmic proteins the most affected. Danofloxacin and enrofloxacin were the FQs with greatest oxidant effects, especially affecting glycolysis and glycogen proteins. Our results suggest that these residues induce irreversible oxidative damage on the main beef proteins and could affect their nutritional value.

Organophosphate pesticides are frequently used to eliminate or prevent insects in poultry. However, their residues may continue in meat after slaughtering. In this study, proteomics and peptidomics approaches were used to evaluate their oxidative impact on myosin and chicken breast proteins under in vitro conditions. Myosin protein was exposed to diazinon and chlorpyrifos showing an increase in its oxidation by increasing times, especially with chlorpyrifos.Then, chicken breast was contaminated with chlorpyrifos to evaluate carbonylation and the effect of simulated gastrointestinal digestion. Proteins were isolated using size-exclusionchromatography and identified by mass spectrometry in tandem. Myosin, β-enolase, CK-M-type and actin were identified as main proteins susceptible to oxidation. Also, oxidised peptides obtained before and after simulated gastrointestinal digestion were identified.Collagen peptides the most susceptible to oxidation. These results suggest that the presence of chlorpyrifos residues on meat could have a negative effect on its final quality and nutritional value.

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Heat shock protein (Hsp90KDa) is a molecular chaperone Background: involved in the process of cellular oncogenesis, hence its importance as a therapeutic target in clinical trials. Geldanamycin is an inhibitor of Hsp90 chaperone activity, which binds to the ATP binding site in the N-terminal domain of Hsp90. However, geldanamycin has shown hepatotoxic damage in clinical trials; for this reason, its use is not recommended. Taking advantage that geldanamycin binds successfully to Hsp90, many efforts have focused on the search for similar analogues, which have the same or better biological response and reduce the side effects of its predecessor; 17-AAG and 17-DMAG are examples of these analogues.In order to know the chemical factors influencing the growth or Methods: decay of the biological activity of geldanamycin analogues, different computational techniques such as docking, 3DQSAR and quantum similarity were used. Moreover, the study quantified the interaction energy between amino acids residues of active side and geldanamycin analogues, through hybrid methodologies and density functional theory (DFT) indexes.The evaluation of interaction energies showed that the interaction Results: with Lys58 residue is essential for the union of the analogues to the active site of Hsp90, and improves its biological activity. This union is formed through a substituent on C-11 of the geldanamycin macrocycle. A small and attractor group was found as the main steric and electrostatic characteristic that substituents on C11 need in order to interact with Lys 58; behavior was

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Objective To describe the current scientific evidence of food-derived bioactive peptides and their angiotensin-converting enzyme inhibiting effect. Methods Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were followed. We searched MEDLINE (through PubMed) and Science Direct databases to identify studies assessing food-derived bioactive peptides and angiotensin-converting enzyme-inhibiting effects. The evidence was organized and presented using tables and narrative synthesis. Results We identified 11 peptides with the best antihypertensive potential: RDGGYCC, LRLESF, FHAPWK, and LVLPG from plants; LSGYGP, ITT, VISDEDGVTH, ATT, and LWHTH from animals; and ALGRV and SPQW from fungi, which demonstrated their antihypertensive potential in vitro and in vivo. Conclusion Overall, food-derived bioactive peptides with hypertensive activity were identified, which shows a promising field as a therapeutic alternative to conventional pharmacological treatments.

Chlorpyrifos (CPF) is an organophosphorus pesticide used in poultry to prevent and/or kill insects and such as preserving agents of poultry feed. Exposure continues to CPF can promote its accumulation at trace concentrations in animal tissue. The toxicological effects of these residues (carcinogenicity, genotoxicity, and neurological disorders) have been related to oxidative stress. Nevertheless, it is still unknown if these trace concentrations might promote oxidative stress in muscle proteins since chicken meat proteins are susceptible to undergo oxidation reactions. Moreover, protein oxidation has been related to a decrease in the nutritional value in of meat. To investigate the oxidative effect of CPF on chicken breast proteins, peptidomics and proteomics analysis were used. For this, chicken breast samples were exposed to CPF and subjected to simulated gastrointestinal digestion. The identification of oxidized peptides from digested and undigested proteins were performed by LC MS/MS (nanoESI qQTOF). Prior to mass analyses undigested proteins were trypsinated. Data were analysed using MASCOT and ProteinPilot v 4.5 software. In this study, 90 and 107 oxidized peptides from digested proteins of control and exposed samples were identified, respectively. These peptides corresponding to 12 oxidized proteins. Meanwhile, 260 and 324 oxidized peptides from undigested proteins (control and exposed samples) were identified, which corresponding to 19 and 17 proteins, respectively. Collagen was protein more susceptible to oxidation promoted by chlorpyrifos in digested and undigested proteins. Identification of these oxidized proteins from simulated digestion provides an important insight about the impact of substances like certain veterinary drugs at trace concentrations on the nutritional value of chicken breast meat.

Contextualización:  El  Bisfenol  A  (BPA por  su  nombre  en  inglés,  Bisphenol  A) es  una  sustancia  química  utilizada  en  la fabricación  de  recipientes  de  plástico  de policarbonato,  recubrimiento  de  latas  de metal,  empaques  de  productos  cosméticos y  de  cuidado  personal,  utensilios  de  cocina, juguetes,  papel  térmico  para  recibos, equipos deportivos y dispositivos médicos y  dentales, que posee la facilidad de lixiviarse con  el  paso  del  tiempo  y  las  altas temperaturas. En la actualidad, el BPA se ha categorizado como disruptor endocrino, debido a su capacidad de alterar la homeostasis del sistema endocrino tanto de humanos como animales. Vacío de investigación: El uso de plásticos se ha convertido en una problemática mundial, debido al impacto generado en los diferentes compartimientos ambientales, así como la salud de los animales y el hombre. En este sentido, se hace necesario la recopilación de información que evidencie el panorama general de los efectos asociados a sustancias presentes en los plásticos, tales como el BPA. Propósito del estudio: Revisar los efectos de disrupción endocrina inducidos por la exposición a BPA en humanos y animales. Metodología: Revisión sistemática de acuerdo con la guía PRISMA. Para ello se realizaron búsquedas en las bases de datos Scielo, ScienceDirect, MedLine (PubMed,OVID) entre el periodo de 2017 hasta 2021. Como palabras claves se emplearon los siguientes términos: Bisphenol, endocrine disrupter, animals y humans. Se incluyeron todos los artículos que evidenciaran el efecto disruptor endocrino del BPA en humanos y animales. Resultados: Para esta revisión se incluyeron 35 estudios, de los cuales 17 se realizaron en humanos y 18 en animales; los estudios seleccionados evidenciaron que la exposición a BPA puede tener efectos sobre la reproducción, aumento de peso (obesógeno), diabetes, neurotoxicidad, estrés oxidativo y función tiroidea. Conclusión: El BPA puede filtrarse de plásticos y productos y ser ingerido o absorbido por vía transdérmica en los seres vivos, así como lixiviarse al ambiente; allí puede alcanzar aguas residuales, suelo y cuerpos de agua (superficiales y subterráneos). Por tanto, esta sustancia es considerada como ubicua en el medio ambiente e inevitable para los humanos y animales, en los cuales ha mostrado inducir efectos de disrupción endocrina equiparables.