RESUMO
This study investigated the production of antioxidant peptides from Porphyra yezoensis through fermentation with three strains of microorganisms: Lactiplantibacillus plantarum L13, Bacillus amyloliquefaciens MMB-02, and Saccharomyces cerevisiae A8. The crude peptides were extracted by aqueous acid precipitation and purified by Sephadex G-25 gel column to produce highly active antioxidant components with molecular weight of <4000 Da. The LC-MS/MS result revealed that the fermentation group contained more hydrophobic amino acids and oligopeptides, which were mainly originated from phycobiliproteins and algal blue proteins. Finally, the antioxidant activity of Porphyra yezoensis was determined with DPPH· and ABTS· scavenging rates of 54.87% and 57.39%, respectively. The ferric ion-reducing power (FRAP) and enzyme activities of SOD and CAT were significantly higher than those of the control group. This study provides a scientific foundation for the deep processing of striped seaweed and contributes to the theoretical understanding of synthetic antioxidant substitutes.
Assuntos
Antioxidantes , Fermentação , Peptídeos , Porphyra , Porphyra/química , Porphyra/metabolismo , Porphyra/microbiologia , Antioxidantes/química , Antioxidantes/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Espectrometria de Massas em Tandem , Bacillus amyloliquefaciens/metabolismo , Bacillus amyloliquefaciens/química , Lactobacillus plantarum/metabolismo , Lactobacillus plantarum/química , Algas ComestíveisRESUMO
Hazardous lead ions (Pb2+) even at a minute level can pose side effects on human health, highlighting the need for tools for trace Pb2+ detection. Herein, we present a DNAzyme-activated CRISPR assay (termed DzCas12T) for sensitive and one-pot detection of lead contamination. Using an extension-bridged strategy eliminates the need for separation to couple the DNAzyme recognition and CRISPR reporting processes. The tandem design endowed the DzCas12T assay with high specificity and sensitivity down to the pM-level. This assay has been used to detect lead contamination in food and water samples, indicating the potential for monitoring lead-associated environmental and food safety.
Assuntos
Sistemas CRISPR-Cas , DNA Catalítico , Chumbo , DNA Catalítico/química , DNA Catalítico/metabolismo , Chumbo/análise , Sistemas CRISPR-Cas/genética , Técnicas Biossensoriais , Limite de Detecção , Contaminação de Alimentos/análise , Poluentes Químicos da Água/análiseRESUMO
A new codelivery system combining prodrug strategy, siRNA/BAplatin @CRGDK NPs, to overcome cisplatin (CDDP) resistance in human breast cancer was designed and researched. Negatively charged siRNA was deposited onto the surface of tumor-targeting peptide-functionalized BAplatin@CRGDK NPs. SiRNA/BAplatin@CRGDK NPs could facilitate cellular uptake of BAplatin and increase the cell proliferation suppression effect of Pt against MDA-MB-231/DDP cells. The tumor-to-kidney uptake ratio of the siRNA/BAplatin@CRGDK NPs in MB-231/DDP tumors is 2.4-fold higher than that of cisplatin in MB-231/DDP tumors, thus giving rise to more significant antitumor efficacy. It demonstrated that the siRNA/BAplatin@CRGDK NPs is a potential, safe, and efficient therapeutic agent for cancer therapy.