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This study aimed to focus on the high-value utilization of raw wheat gluten by determining the potent antioxidant peptides and angiotensin I-converting enzyme (ACE) inhibitory peptides from wheat gluten oligopeptides (WOP). WOP were analyzed for in vitro antioxidant activity and inhibition of ACE, and the identification of active peptides was performed by reversed-phase high-performance liquid chromatography and mass spectrometry. Quantitative analysis was performed for highly active peptides. Five potent antioxidant peptides, Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (6.07 ± 0.38, 7.28 ± 0.29, 11.18 ± 1.02, 5.93 ± 0.20 and 9.04 ± 0.47 mmol 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) equivalent/g sample, respectively), and five potent ACE inhibitory peptides, Leu-Tyr, Leu-Val-Ser, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (half maximal inhibitory concentration (IC50) values = 0.31 ± 0.02, 0.60 ± 0.03, 2.00 ± 0.13, 1.47 ± 0.08 and 1.48 ± 0.11 mmol/L, respectively), were observed. The contents of Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser were 155.04 ± 8.36, 2.08 ± 0.12, 1.95 ± 0.06, 22.70 ± 1.35, 0.25 ± 0.01, and 53.01 ± 2.73 μg/g, respectively, in the WOP. Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser are novel antioxidative/ACE inhibitory peptides that have not been previously reported. The results suggest that WOP could potentially be applied in the food industry as a functional additive.

Wheat gluten was hydrolyzed with both alkaline protease and neutral protease to produce high-protein and low-wheat-weight oligopeptides (WOP), which was subjected to a multistage purification. Then, high performance liquid chromatography was applied to separate WOP. In order to identify WOP sequences, six major fractions were gathered for mass spectrometry. A total of 15 peptides were synthesized for further in vitro analyses of their antithrombotic activity, vasorelaxation activity, and cholesterol reducing activity. Two antithrombotic peptides (ILPR and ILR), three vasorelaxant peptides (VN, FPQ, and FR), and four cholesterol-lowering peptides (QRQ, ILPR, FPQ, and ILR) were identified. These active peptides in WOP were also quantified. These peptides are novel candidate peptides with vascular disease suppressing effects. The results indicate WOP as good protein sources for multifunctional peptides.

Corn gluten meal (CGM) was hydrolyzed by Alcalase 2.4L and Protex 7L to obtain low-molecular-weight peptides. The antioxidant and angiotensin-I-converting enzyme (ACE) inhibitory activities of the peptides were determined by 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) free radical scavenging activity, the JHH7 cell oxidative stress model, and the ACE inhibition assay, respectively. Corn peptides (CPs) had strong antioxidant capacity to scavenge ABTS radicals (1.44 ± 0.11 mmol/g), and significantly reduced reactive oxygen species and malondialdehyde levels in oxidized JHH7 cells, increasing superoxide dismutase, catalase, and glutathione peroxidase activities by 26.20%, 147.52%, and 43.20%, respectively, at the concentration of 800 μg/mL. CPs had high ACE inhibitory activity, with an IC50 value of 0.27 ± 0.05 mg/mL. Next, the CPs were separated by reverse-phase high-performance liquid chromatography. Twelve fractions were collected, and their ABTS free radical scavenging and ACE inhibitory activities were determined. Fractions 1, 2, 3, 4, and 9 showed higher ABTS free radical scavenging and ACE inhibitory activities. Twelve peptides were identified from active fractions by liquid chromatography–tandem mass spectrometry (LC–MS/MS) as Leu-Ser-Pro-Tyr, Leu-Asn-Ser-Pro-Ala-Tyr, Tyr-Gly-Pro-Gln, Pro-Pro-Tyr, Ala-Tyr-Pro-Glu, Thr-Tyr-Ser-Gly-Pro-Lys, Ala-Tyr-Pro-Gly-Pro-Gln, Leu-Ala-Tyr-Pro-Gln, Ala-Tyr-Leu-Gln-Gln-Gln, Ser-Ala-Pro, Asn-Ala-Pro, and Val-Asn-Ala-Pro. These peptides exhibited good ABTS free radical scavenging and ACE inhibitory activities. Therefore, CPs may have potential applications in the food industry as functional material additives.

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Mining activities have led to Cu and Cd contaminated of surrounding agricultural soil. To decrease the Cu and Cd accumulation in crops, the Ricinus communis L. (castor) has been used for phytoremediation. A pot experiment was served to investigate the effect of phosphate fertilizer (Ca(H2PO4)2) on the growth and Cu/Cd uptake of castor in contaminated soil. The results showed that the application of P fertilizer improved the leaf cell morphology, decreased the malonaldehyde (MDA) content of castor leaves, and increased the plant biomass (28.2–34.2%). Besides, phosphate fertilizer still facilitated accumulation Cu and Cd by castor. The addition of phosphate fertilizer increased the contents of Cu in the root of castor, improved the bioconcentration factor (BCF) of Cu, and observably enhanced the accumulation of Cu (up to 201 μg/plant) in castor. Applying phosphorus increased the percentage of residual Cd, diminished the percentage of acid extractable Cd in soil, and the accumulation of Cd in castor was not significantly increased. These results suggest that phosphorus alleviated the stress of heavy metals on castor leaves and enhanced the accumulation of Cu and Cd in castor by promoting the growth of castor. Applying phosphate fertilizer effectively alleviated the stress of heavy metals on castor and significantly increased the biomass of castor.The reason of applying phosphorus enhanced the castor uptake Cu and Cd was that phosphorus promoted the growth of castor.Applying phosphorus markedly increased the percentage of residual Cd but diminished the percentage of acid extractable Cd in soil. Applying phosphate fertilizer effectively alleviated the stress of heavy metals on castor and significantly increased the biomass of castor. The reason of applying phosphorus enhanced the castor uptake Cu and Cd was that phosphorus promoted the growth of castor. Applying phosphorus markedly increased the percentage of residual Cd but diminished the percentage of acid extractable Cd in soil.

Background An accurate diagnosis for high-suspicion nodules based on the 2015 American Thyroid Association (ATA) guidelines would reduce unnecessary invasive examinations. Elastography is a useful tool for discriminating benign and malignant thyroid nodules. The aim of this study is to investigate the diagnostic efficiency of elastography for high-suspicion thyroid nodules based on the 2015 ATA guidelines in the Chinese population. Methods Thyroid nodules with high-suspicion characteristics based on the 2015 ATA guidelines were subjected to conventional ultrasound (US) and ultrasound strain elastography (USE) examinations at 12 hospitals from 4 geographic regions across China. Cytology/histology of thyroid nodules was used as a reference method. Receiver operating characteristic (ROC) curves were plotted to evaluate the diagnostic performance of the elasticity score (ES) and strain ratio (SR). Logistic regression analysis was used to determine the predictors of malignancy. Results Overall, a total of 1445 thyroid nodules (834 malignant, 611 benign) from 12 centers were included in the final analysis. The areas under the curve of the ES and SR were 0.828 and 0.732, respectively. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the ES were 92.4, 60.7, 79.0, 76.3 and 85.5%, respectively, and those of the SR were 81.1, 50.1, 68.9, 65.9 and 67.9%, respectively. The combination of the Thyroid Imaging Reporting and Data System (TI-RADS) and ES led to a significant increase in the sensitivity and NPV (97.1 and 91.9%, respectively) compared with the TI-RADS alone. Logistic regression analysis showed that microcalcifications (OR = 5.290), taller than wide (OR = 12.710), irregular margins (OR = 10.117), extrathyroidal extension (ETE; OR = 6.412), the ES (OR = 3.741) and the SR (OR = 1.083) were independent predictors of malignant thyroid nodules. The sensitivity, specificity, accuracy, PPV and NPV of the ES were all superior in nodules ≥1 cm than in those Conclusions Elastography combined with the ES is a valuable tool for the assessment of high-suspicion thyroid nodules based on the 2015 ATA guidelines, especially in nodules ≥1 cm.