Effect of cooking and in vitro digestion on the peptide profile of chicken breast muscle and antioxidant and alcohol dehydrogenase stabilization activity
FOOD RESEARCH INTERNATIONAL
Authors: Xiao, Chuqiao; Toldra, Fidel; Zhou, Feibai; Gallego, Marta; Zhao, Mouming; Mora, Leticia
Abstract
The present study aimed to investigate the effect of cooking and simulated gastrointestinal digestion on the antioxidant and alcohol dehydrogenase (ADH) stabilization activity of peptides extracted from chicken breast muscle. Results showed that cooking would not affect peptide bioactivity, whereas further digestion using gastrointestinal enzymes could lead to significant changes, producing an increase in ORAC (112.5 to 682.0 uM TE/g) and ABTS radical scavenging activities (164.0 to 848.9 uM TE/g), whereas a decrease in DPPH radical scavenging (from 36.1% to 4.4%), ferric-reducing power (OD 700 from 0.50 to 0.15) and ADH stabilization activities (from 44.1% to 20.5%) was observed. The peptidomic analysis resulted in the identification and relative quantitation of 777 peptides from 76 different parent proteins and evidenced that peptides derived from thin and collagen were mainly responsible for the differences detected in the peptide profile. The decrease of DPPH radical scavenging, ferric reducing power, and ADH stabilization activity may result from the release of inactive peptides containing oxidized residues, mainly from collagen, leading to the loss of efficacy of active sequences. The results confirmed the importance of collagen derived peptides on the antioxidant and ADH stabilization activity observed in chicken breast as well as the negative impact of oxidation on the bioactivity of generated peptides after simulated gastrointestinal digestion. Nevertheless, further work would be needed to confirm the peptide sequences responsible for the observed bioactivity.
Sequencing two Tyr::CreER(T2) transgenic mouse lines
PIGMENT CELL & MELANOMA RESEARCH
Authors: Aktary, Zackie; Corvelo, Andre; Estrin, Camille; Larue, Lionel
Abstract
The Cre/loxP system is a powerful tool that has allowed the study of the effects of specific genes of interest in various biological settings. The Tyr::CreER(T2) system allows for the targeted expression and activity of the Cre enzyme in the melanocyte lineage following treatment with tamoxifen, thus providing spatial and temporal control of the expression of specific target genes. Two independent transgenic mouse models, each containing a Tyr::CreER(T2) transgene, have been generated and are widely used to study melanocyte transformation. In this study, we performed whole genome sequencing (WGS) on genomic DNA from the two Tyr::CreER(T2) mouse models and identified their sites of integration in the C57BL/6 genome. Based on these results, we designed PCR primers to accurately, and efficiently, genotype transgenic mice. Finally, we discussed some of the advantages of each transgenic mouse model.