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In this study, the changes in flavor characteristics of tartary buckwheat (TB) roasting at temperatures of 160 °C, 180 °C, 200 °C, and 220 °C for 8 min were evaluated by chromatography-ion mobility spectrometry (GC-IMS), headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), electronic nose (E-nose), and electronic tongue (E-tongue). 52 volatile compounds were identified by GC-IMS, including 9 esters, 21 aldehydes, 6 ketones, 1 lactone, 7 alcohols, 1 acid, 4 furans, 1 pyrazine, and 2 monoterpenes. 36 compounds were quantified by HS-SPME-GC-MS, and 8 volatiles with odor activity values (OAV) ＞ 1 contributed to the overall TB aroma. Notably, 2-ethyl-3-methylpyrazine and 3,5-diethyl-2-methylpyrazine were identified as the aroma-active compounds in the 180 °C, 200 °C, and 220 °C roasting groups. Additionally, principal component analysis (PCA) based on the signal intensity of the detected flavor compounds revealed the TB samples from NC and the four roasting groups could be distinguished effectively. Our results indicated that roasting substantially enhanced the overall aroma intensity of TB. Overall, 180 °C of roasting was beneficial from the flavor point of view for the obtained TB. In conclusion, our findings suggest that roasting at 180 °C is the most favorable option from a flavor perspective for achieving high-quality TB. • HS-SPME-GC-MS, GC-IMS, E-nose, and E-tongue were used to study and characterize flavor compounds of TB. • 52 VOCs were identified by GC-IMS. • 8 characteristic aroma compounds of TB were screened based on HS-SPME-GC-MS and OAV. • Pyrazines increased after roasting. • PCA successfully distinguish TB roasted at different temperatures. [ABSTRACT FROM AUTHOR]

Abstract: This work demonstrates the process of building optoelectrically cooperative surface wetting in smart and precise way. The superhydrophobic photosensitive film is constructed with TiO2 nanotube arrays. Compared with conventional organic dyes, CdS quantum dots (QDs) as sensitizer layer are modified on TiO2 nanotubes surface to improve photosensitivity of the composited surface in visible light region, which offer the benefit for designing and fabricating solid state hetero-junction devices. ITO glass is introduced as top electrode to apply electrical and optical stimuli and the patterned wetting is instantly obtained with masking light through ITO. The optoelectrically cooperative wettability conversion occurred on superhydrophobic TiO2 nanotube surface at critical voltage of 12V, which was decreased by 18V comparing with only using electric stimulus. This study provides potential applications for TiO2 nanotube arrays to the associated research of liquid reprography, location-controlled microfluidic device and lab-on-chip. [Copyright &y& Elsevier]

[Display omitted] • MIR is more effective than NIR to determine the caprolactam content in sauces. • Three data fusion methods were used for quantify caprolactam. • Model for caprolactam detection in sauces was developed with R p 2 of 0.9961. In this study, we aimed to quantify caprolactam content in sauce-based food using near-infrared (NIR) and mid-infrared (MIR) spectroscopy, combined with chemometrics and data fusion strategy. Sauce-based food samples with different caprolactam levels were prepared. Partial least squares (PLS) and support vector machine (SVM) regression models were developed based on NIR and MIR spectral data. The high-level fusion model showed the best performance for quantifying caprolactam for sauces, with square of correlation coefficient of prediction (R p 2) in range of 0.9929−0.9990 and root mean square error of prediction (RMSEP) in range of 1.0794–2.9303 mg kg−1. Finally, a comprehensive model of caprolactam content in sauces was established with R p 2 of 0.9961 and RMSEP of 2.1505. These findings indicated that a combination of NIR and MIR spectroscopy as high-level fusion strategy can achieve rapid, non-destructive, and accurate quantification of caprolactam content in sauces and hence can be used for monitoring the safety of food. [ABSTRACT FROM AUTHOR]

The purpose of this study was to isolate, purify, identify, and characterize novel antioxidant peptides derived from bovine blood hydrolysates (BBH). Results showed that, BBH, obtained by two-step flavourzyme-alcalase hydrolysis, was used to obtain five fractions by ultrafiltration and gel filtration chromatography, where the Fraction B had the strongest antioxidant capacity. Five novel antioxidant peptides (GFAGDDAPRA, SGPGIHVR, APSADAPM, TQRFFESF and HVDPENFKLL) were identified utilizing RP-HPLC and LC-MS/MS, and exhibited excellent free radical scavenging ability. GFAGDDAPRA and TQRFFESF possessed the highest ABTS radical scavenging rate (95.70% and 93.20%, respectively), and the DPPH radical scavenging rate of APSADAPM was the highest (50.28%). Moreover, these five peptides could be docked with Recombinant Kelch Like ECH Associated Protein 1 (Keap1) with the binding energies less than −5 kcal/mol, which indicated that they may be able to promote the body's antioxidant capacity by activating the Keap1-Nrf2 signaling pathway of cell. Meaningfully, this work shed new light on the processing and utilization of bovine blood, as well as offered a valuable foundation for the study and development of food-borne antioxidant peptides. • The antioxidant activity of bovine blood hydrolysate was investigated. • Peptides were isolated and purified by ultrafiltration, gel filtration chromat-ography, and RP-HPLC. • Purified Fraction B5 and Fraction B6 displayed highest antioxidant activity. • Five novel antioxidant peptide sequences were identified by LC-MS/MS. • Identified peptides showed promise in activating the Keap1-Nrf2 pathway. [ABSTRACT FROM AUTHOR]

Malonyl-CoA is an important building block for microbial synthesis of numerous pharmaceutically interesting or fatty acid-derived compounds including polyketides, flavonoids, phenylpropanoids and fatty acids. However, the tightly regulated intracellular malonyl-CoA availability often impedes overall product formation. Here, in order to unleash this tightly cellular behavior, we present evolution: dual dynamic regulations-based approaches to write artificial robust and dynamic function into intricate cellular background. Firstly, a conserved core domain based evolutionary principles were incorporated into genome mining to explore the biosynthetic diversities of discrete acetyl-CoA carboxylase (ACC) families, as malonyl-CoA is solely derived from carboxylation of acetyl-CoA by ACC in most organisms. A comprehensive phylogenomic and further experimental analysis, which included genomes of 50 strains throughout representative species, was performed to recapitulate the evolutionary history and reveal that previously unnoticed ACC families from Salmonella enterica exhibited the highest activities among all the candidates. A set of orthogonal and bi-functional quorum-sensing (QS)-based regulation tools were further designed and connected with T7 RNA polymerase as genetic amplifier to achieve dual dynamic control in a high dynamic range, which allowed us to efficiently activate and repress different sets of genes dynamically and independently. These genetic circuits were then combined with ACC of S. enterica and CRISPRi system to reprogram central metabolism that rewired the tightly regulated malonyl-CoA pathway to a robust and autonomous behavior, leading to a 29-fold increase of malony-CoA availability. We applied this dual regulation tool to successfully synthesizing malonyl-CoA-derived compound (2S)-naringenin, and achieved the highest production (1073.8 mg/L) reported to date associate with dramatic decreases of by-product formation. Notably, the whole fermentation presents as an autonomous behavior, totally eliminating human supervision and inducer supplementation. Hence, the constructed evolution: dual dynamic regulations-based approaches pave the way to develop an economically viable and scalable procedure for microbial production of malonyl-CoA derived compounds. • The tightly regulated malonyl-CoA pathway was rewired to a robust and autonomous behavior. • The highest activity of ACC enzymes has been identified. • A conserved core domain based evolutionary principles were proposed. • The highest (2S)-naringenin titer was achieved without human supervision. [ABSTRACT FROM AUTHOR]

Background Microskin autografts with conventional wrap and compression are used extensively in the treatment of skin and tissue defects. This comparative study aimed at investigation of the clinical application of negative pressure wound therapy (NPWT) in combination with microskin autografts for repair of acute and chronic wounds. Methods A prospective case-control study was performed from December 1, 2010-December 31, 2013 in Changhai Hospital, Shanghai. We compared a study group of patients received microskin autografting covered by NPWT with that of a control group of patients received microskin autografting covered by a conventional gauze. Results A total of 81 patients were in this study, 27 patients were allocated to the study group and 54 patients to the control group. The study group exhibited significant low infection rate and pain score during removal of inner layer at first dressing change after skin grafting compared with those of the control group (P < 0.05). The time interval between skin grafting and first postoperative change was longer in the study group than that in the control group (P < 0.01), the study group showed a significant shorter 95% wound healing time (P < 0.05), and survival rate of microskin autografts in the study group was higher than that in the control group (P < 0.05). Conclusions NPWT is beneficial for wound closure after microskin autografts, which prolongs the interval between skin transplantation and first postoperative dressing change, reduces pain during removal of inner layer dressing, increases skin graft survival rate, and shortens wound healing time. Therefore, NPWT can be recommended for repair of acute and chronic wounds with microskin autografts. [ABSTRACT FROM AUTHOR]

Abstract: Evodiamine, the major bioactive alkaloid isolated from Wu-Chu-Yu, has been shown to interact with a wide variety of proteins and modify their expression and activities. In this study, we investigated the interaction between evodiamine and the aryl hydrocarbon receptor (AhR). Molecular modeling results revealed that evodiamine directly interacted with the AhR. Cytosolic receptor binding assay also provided the evidence that evodiamine could interact with the AhR with the Ki value of 28.4±4.9nM. In addition, we observed that evodiamine suppressed the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced nuclear translocation of the AhR and the expression of CYP1A1 dose-dependently. These results suggested that evodiamine was able to bind to the AhR as ligand and exhibit antagonistic effects. [ABSTRACT FROM AUTHOR]

Abstract: Based on sonochemical technique, large-scale PbS nanobelts are successfully synthesized in the mixed solution of PbCl2 and Na2S2O3. These nanobelts are characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), selected area electronic diffraction, energy dispersive X-ray spectroscopy, and high-resolution TEM. The as-synthesized PbS nanobelts have width of about 80nm, length up to several millimeters, and width-to-thickness ratio of about 5. In addition, the growth mechanism of PbS nanobelts is suggested. [Copyright &y& Elsevier]