Influence of germination and roasting on the characteristic volatile organic compounds of quinoa using sensory evaluation, E-nose, HS-GC-IMS, and HS-SPME-GC-MS.

This study aimed to investigate the effects of germination and roasting on the flavor of quinoa. Firstly, the aroma of quinoa and germinated quinoa roasted under different conditions was analyzed using sensory evaluation and electronic nose (E-nose). Results showed that the best favorable aroma of quinoa and germinated quinoa was obtained when roasted at 160 °C for 15 min. Then, a total of 34 and 80 volatile organic compounds (VOCs) of quinoa and germinated quinoa roasted at 160 °C for 15 min were determined using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), respectively. Germination and roasting effectively reduced the contents of VOCs that produced undesirable flavor. Moreover, germination improved the floral aromas, while roasting mainly produced caramel, cocoa, and roasted nut aromas of quinoa. This study indicated that germination and roasting treatments might serve as promising processing methods to improve the flavor of quinoa.

Epstein-Barr-Virus-Driven Cardiolipin Synthesis Sustains Metabolic Remodeling During B-cell Lymphomagenesis.

Epstein-Barr Virus (EBV) is associated with a range of B-cell malignancies, including Burkitt, Hodgkin, post-transplant, and AIDS-related lymphomas. Studies highlight EBV's transformative capability to induce oncometabolism in B-cells to support energy, biosynthetic precursors, and redox equivalents necessary for transition from quiescent to proliferation. Mitochondrial dysfunction presents an intrinsic barrier to EBV B-cell immortalization. Yet, how EBV maintains B-cell mitochondrial function and metabolic fluxes remains unclear. Here we show that EBV boosts cardiolipin(CL) biosynthesis, essential for mitochondrial cristae biogenesis, via EBNA2-induced CL enzyme transactivation. Pharmaceutical and CRISPR genetic analyses underscore the essentiality of CL biosynthesis in EBV-transformed B-cells. Metabolomic and isotopic tracing highlight CL's role in sustaining respiration, one-carbon metabolism, and aspartate synthesis, all vital for EBV-transformed B-cells. Targeting CL biosynthesis destabilizes mitochondrial one-carbon enzymes, causing synthetic lethality when coupled with a SHMT1/2 inhibitor. We demonstrate EBV-induced CL metabolism as a therapeutic target, offering new strategies against EBV-associated B-cell malignancies.

Quinoa protein and its hydrolysate ameliorated DSS-induced colitis in mice by modulating intestinal microbiota and inhibiting inflammatory response.

The objective of this study was to investigate the protective effects of quinoa protein (QPro) and its derived peptides (QPep) in dextran sulfate sodium (DSS)-induced colitis in mice. The results demonstrated that oral administration of QPro and QPep significantly alleviated colitis symptoms, including diarrhea, abdominal pain, bloody stools, weight loss, as well as reduced colonic shortening, inflammatory factor release, and intestinal barrier injury. Short-chain fatty acids (SCFAs) production rose as QPro and QPep modulated the composition of the intestinal microbiota. Western blotting results revealed that QPro and QPep also suppressed TLR4 levels and inhibited IκB-α and NF-κB phosphorylation in colon tissue, implying that the TLR4/IκB-α/NF-κB signaling pathway may be involved in the amelioration of QPro and QPep in DSS-induced colitis. These results indicate the potential of quinoa protein and its hydrolysate to serve as bioactive components in functional diets for intestinal health and to significantly lower intestinal inflammation.

Absorption of egg white hydrolysate in the intestine: Clathrin-dependent endocytosis as the main transport route.

This paper aimed to investigate the in vivo absorption of egg white hydrolysate (EWH) in rats and the transport route across the intestinal epithelium. Results showed that the level of plasma peptide-bound amino acid (PAA) of the EWH-supplemented rats (EWH-R) was determined to be 2012.18 ± 300.98 µmol/L, 10.72% higher than that of the control group, and was significantly positively correlated to that of EWH. Thirty-three egg white-derived peptides were successfully identified from the plasma of EWH-R, and 20 of them were found in both EWH-R plasma and EWH, indicating that these peptides tend to be absorbed through the intestinal epithelium in intact forms into the blood circulation. In addition, 637 up-regulated and 577 down-regulated genes in Caco-2 cells incubated with EWH were detected by RNA-sequencing and the clathrin-dependent endocytosis was the most enriched pathway in KEGG analysis. EWH significantly increased the mRNA levels of the key genes involved in the clathrin-dependent endocytosis but these changes would be inhibited by the clathrin-dependent endocytosis inhibitor of chlorpromazine. Moreover, the transepithelial transport of EWH across Caco-2 cell monolayers was significantly reduced by chlorpromazine. This study provided molecular-level evidence for the first time that clathrin-dependent endocytosis might be the main transport route of EWH in the intestinal epithelium.

Quinoa Peptides Alleviate Obesity in Mice Induced by a High-Fat Diet via Regulating of the PPAR-α/γ Signaling Pathway and Gut Microbiota.

SCOPE: The obesity epidemic continues to be a major global public health threat with limited effective treatments. Peptides are a group of promising bioactive molecules. Both in vivo and in vitro studies have demonstrated that quinoa has potential prebiotic benefits. Thus, the present study aims to investigate the influence of quinoa peptides (QP) consumption on obesity and its underlying mechanisms in high-fat diet (HFD)-induced mice. METHODS AND RESULTS: QP (1000 mg kg-1  day-1 ) is administered to HFD mice for 8 weeks, and is found to significantly reduce the body weight, and plasma levels of triacylglycerol (TG) and total cholesterol (TC) compare to the HFD group. In addition, QP significantly decreases lipid accumulation in the liver caused by HFD. The liver transcriptome analysis shows that the alleviation of QP on obesity is related to the PPAR signaling pathway. QP upregulates the expressions of PPAR-α and its related genes and downregulates the expressions of PPAR-γ and its downstream genes. Furthermore, QP remodels the community composition of gut microbiota by lowering the ratio of Firmicutes c Bacteroidetes (F/B). CONCLUSION: These findings suggest that QP consumption alleviates HFD-induced obesity by regulating the PPAR-α/γ signaling pathway in the liver and community structure of gut microbiota.

Preparation of quinoa protein with ultrasound pretreatment and its effects on the physicochemical properties, structural and digestion characterizations.

This study aimed to investigate the effects of ultrasound pretreatment on the yield and the physicochemical properties, structural and digestion characterizations of quinoa protein (QP). Results showed that under the conditions of ultrasonic power density of 0.64 W/mL, ultrasonication time of 33 min, and the liquid-solid ratio of 24 mL/g, the highest yield of QP at 68.403 % was obtained, which was significantly higher than that without ultrasound pretreatment at 51.26 ± 1.76 % (P < 0.05). Ultrasound pretreatment decreased the average particle size and ζ-potential but increased the hydrophobicity of QP (P < 0.05). However, no significant protein degradation and secondary structure changes of QP by ultrasound pretreatment were observed. In addition, ultrasound pretreatment slightly improved the in vitro digestibility of QP and reduced the dipeptidyl peptidase IV (DPP-IV) inhibitory activity of the hydrolysate of QP by in vitro digestion. Overall, this work demonstrates that ultrasound-assisted extraction is appropriate for improving the extraction efficiency of QP.

Preparation and identification of dipeptidyl peptidase IV inhibitory peptides from quinoa protein.

The objective of this study was to investigate the dipeptidyl peptidase IV (DPP-IV) inhibitory properties of quinoa protein-derived peptides. After germination, quinoa protein was extracted and then hydrolyzed by different enzymes such as papain, Alcalase, Neutrase, and Flavourzyme and pepsin-trypsin digestion. Results showed that the quinoa protein hydrolysates (QPH) by pepsin-trypsin digestion displayed the highest DPP-IV inhibitory activity. When ultrafiltrated, the fraction of quinoa protein hydrolysate with molecular weight less than 1 kDa (QPH1) exhibited a superior DPP-IV inhibitory activity with IC50 of 3.40 ± 0.20 mg/mL in vitro and 2.20 ± 0.29 mg/mL in Caco-2 based in situ. Furthermore, the peptide sequences of QPH1 were identified by UPLC-MS/MS. Twenty quinoa-derived peptides were determined with in vitro DPP-IV inhibitory activities with IC50 values less than 500 µM. The peptides IPI, IPV, VAYPL and IPIN showed the highest in vitro DPP-IV inhibitory activities with IC50 of 5.25 ± 0.16, 26.15 ± 0.58, 42.93 ± 1.15, and 56.58 ± 3.36 µM, respectively. The in situ DPP-IV activities of Caco-2 cells were also attenuated by these four peptides with IC50 of 10.75 ± 0.87, 29.11 ± 1.79, 61.9 ± 4.23, and 92.59 ± 12.89 µM, respectively. Moreover, these four peptides were identified as competitive inhibitors of DPP-IV. Molecular docking showed that quinoa peptides IPI and IPV were predicted to form multiple hydrogen bonds, attractive charge, and hydrophobic interactions with the residues of active site of DPP-IV. This study confirms that quinoa protein is a good source for DPP-IV inhibitory peptides and has potential as ingredients in functional foods for the prevention or management of type 2 diabetes.

Identification and Characterization of Dipeptidyl Peptidase-IV Inhibitory Peptides from Oat Proteins.

In this study, flavourzyme, papain, neutrase, and alcalase, as well as gastrointestinal digestion simulated with pepsin and pancreatin, were used to hydrolyze oat protein, and the dipeptidyl peptidase-IV (DPP-IV) inhibitory activities of the oat protein hydrolysates were investigated. The results indicated that the oat protein hydrolysate by neutrase showed the most potent DPP-IV inhibitory property with an IC50 value of 2.55 ± 0.38 mg/mL. Using UPLC-MS/MS, ten new DPP-IV inhibitory peptides were identified from the oat protein hydrolysate by neutrase. Among these peptides, IPQHY, VPQHY, VAVVPF, and VPLGGF exhibited the strongest DPP-IV inhibitory activity with IC50 values below 50 µM, and all of them acted as mixed-type inhibitors. Molecular docking indicated that the above four oat-derived peptides were predicted to form hydrogen bonds, attractive charge, and hydrophobic interactions with the residues of the active site of DPP-IV. Therefore, our results suggest that oat is an excellent protein source for food-derived DPP-IV inhibitory peptides and it has the prospect of becoming a dietary supplement for T2DM.