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Objective: To investigate the effects of electron beam irradiation on the physicochemical properties and antioxidant activity of non-waxy and waxy proso millet. Methods: waxy (‘Yushu 1’) and non-waxy (‘Yumi 2’) proso millet were subjected to electron beam irradiation at different doses of 0 (control), 2, 4, 6, 8, and 10 kGy and were evaluated for physicochemical properties, bioactive substances and antioxidant capacity. Results: After electron beam irradiation, the color, starch content, ash content, phenolic content and antioxidant activity of non-waxy and waxy proso millet changed significantly (P 0.05). In addition, electron beam irradiation treatment significantly increased the contents of total phenols and total flavonoids, antioxidant activity and individual phenolic contents in non-waxy and waxy proso millet; the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity increased up to 78.01% and 70.22%, and the 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation scavenging capacity increased up to 61.51% and 50.57%, respectively. The contents of gallic acid, caffeic acid, resveratrol, catechin and kaempferol in proso millet extract increased, while the contents of protocatechuic acid and epicatechin remained relatively stable. The correlation analysis suggested that the total phenolic content had a significantly positive correlation with the contents of catechin and quercetin (P < 0.01), the total flavonoid content had a significantly positive correlation with the contents of rutin and gallic acid (P < 0.01), and the antioxidant activity was positively correlated with the catechin content. Compared with the control, proso millet treated with electron beam irradiation exhibited stronger antioxidant properties and higher phenolic contents, which would be worthy of further research and development.

Summary: The purpose of this study was to investigate the fermentation characteristics of five varieties of fig juices (Ficus carica cv. Siluhongyu, Siluhuangjin, Silufeicui, Jinaofen and Fengchanhuang) by two select strains (Lactobacillus plantarum and Lactobacillus acidophilus), based on the changes of physicochemical parameters, bioactive components, antioxidant activities and flavour volatiles. Viable counts were above 9.5 log CFU mL−1 throughout the fermentation process, indicating that fig juices were suitable substrates for strain proliferation. Total phenolic and flavonoid contents were significantly enhanced during fermentation, particularly with Siluhuangjin by L. plantarum and Silufeicui by L. acidophilus, exhibiting the highest total phenolic (465 mg GAE L−1) and total flavonoid contents (152 mg RE L−1), respectively. Accordingly, antioxidant activities based on SOD, DPPH, ABTS and FRAP methods were significantly improved after fermentation (P < 0.05). SOD and ABTS were positively correlated with contents of protocatechuic acid and caffeic acid, respectively (P < 0.05). Furthermore, alcohols, ketones and terpenoids contents were increased, while aldehydes content was decreased significantly after fermentation (P < 0.05), suggesting the improved flavour characteristics of fermented fig juices. [ABSTRACT FROM AUTHOR]

Umami peptides are important taste components of foods. In this study, umami peptides from Hypsizygus marmoreus hydrolysate were purified through ultrafiltration, gel filtration chromatography, and RP-HPLC, and then identified using LC-MS/MS. The binding mechanism of umami peptides with the receptor, T1R1/T1R3, was investigated using computational simulations. Five novel umami peptides were obtained: VYPFPGPL, YIHGGS, SGSLGGGSG, SGLAEGSG, and VEAGP. Molecular docking results demonstrated that all five umami peptides could enter the active pocket in T1R1; Arg277, Tyr220, and Glu301 were key binding sites; and hydrogen bonding and hydrophobic interaction were critical interaction forces. VL-8 had the highest affinity for T1R3. Molecular dynamics simulations demonstrated that VYPFPGPL (VL-8) could be steadily packed inside the binding pocket of T1R1 and the electrostatic interaction was the dominant driving force of the complex (VL-8-T1R1/T1R3) formation. Arg residues (151, 277, 307, and 365) were important contributors to binding affinities. These findings provide valuable insights for the development of umami peptides in edible mushrooms. [ABSTRACT FROM AUTHOR]

Subcritical water extraction (SWE) and hot water extraction (HWE) were used to extract polysaccharides from Morchella sextelata (MSP). The physicochemical and structural characteristics and biological properties of MSPSWE and MSPHWE were evaluated. SWE achieved a higher crude MSP yield (18.09 ± 0.09%) than HWE (4.95 ± 0.05%; p <.01). Using SWE, MSPSWE showed a higher total sugar content and fat‐binding capacity. MSPSWE and MSPHWE contained the same monosaccharides, but with significantly different average molecular weights and microstructures without alterations in the main chemical structure, as revealed via FT‐IR and nuclear magnetic resonance (NMR) spectroscopy. DSC analysis revealed favorable thermal stability. Biological activity assays elucidated that MSPSWE had stronger antioxidant activity in vitro and significantly promoted RAW264.7 cell proliferation and nitric oxide production. Therefore, MSPSWE may represent a potent antioxidant and immunomodulator in the functional food field, with SWE serving as an effective method for extracting highly bioactive M. sextelata polysaccharides. Novelty impact statement: The molecular weight of Morchella sextelata polysaccharides (MSPs) decreased following subcritical water extraction (SWE), which also improved their yield (from 4.95% to 18.09%). Furthermore, the MSPs obtained via SWE showed stronger antioxidant and immunomodulatory activities than those obtained via hot water extraction. [ABSTRACT FROM AUTHOR]

Considering the conventional federated filtering-based fault-tolerant integrated navigation system is difficult to be implemented by serial data processing circuits, this paper presents navigation switching strategy-based SINS/GPS/ADS/DVL fault-tolerant integrated navigation system to guarantee the reliability of integrated navigation system under sensor faults. When sensor failure appears, SINS and fault-free sensors are selected successively to form an integrated navigation system, such that reliable navigation parameters can be obtained. The simulation tests are implemented to verify that the SINS/GPS/ADS/DVL integrated navigation system can provide reliable navigation parameters when ADS and DVL are disabled. [ABSTRACT FROM AUTHOR]

The navigation accuracy of laser strap-down inertial navigation products declines with gyro dither, which is a bottleneck problem for the development of the important aviation instrument. The reason is that the dither of three gyros in the product couples and generates extra noise in the output signals of gyros. To decouple dither, this paper applies the vibration absorber in laser inertial navigation products. First of all, an angular vibration model of the three-rigid body system, which is constructed by the gyro, platform, and vibration absorber, is established. Then, the theoretical restriction of the absorber and the system response are derived. Finally, considering the power limitation for dither, the total power of the vibration system is analyzed. The analytical and experimental results show that the efficiency of the vibration absorber only relates to the frequency offset with gyros, and the absorber does lead to a sharp power increase. [ABSTRACT FROM AUTHOR]

To overcome the problems of poor structural reliability, high driving voltage and small scanning angle, a novel electromagnetic MOEMS scanning grating mirror (SGM) with folded torsion beam is reported in this work. Compared with the conventional straight torsion beam, the folded torsion beam has better elastic torsion property and can effectively improve the structural reliability of the MOEMS SGM. Furthermore, the fillet structure is added to the folded torsion beam to prevent stress concentration. The stress analysis and impact resistance of the proposed MOEMS SGM are simulated by FEM (ANSYS 18.2), and the simulation results are compared with that of the MOEMS SGM without fillet structure. The stress simulation is carried out under different fillet radius of 40–70 μ m, the maximum stress can be reduced to 85 % and the stress is redistributed uniformly. Meanwhile, in the impact resistance simulation, the impact displacement can be reduced by 10.1 %. A prototype is fabricated and tested, it has a large mirror area of 6 mm ×7 mm. The MOEMS SGM can reach the maximum scanning half angle of 6. 1 ∘ at 7.63 V under resonance (@602.1 Hz), which means that the full mechanical scanning angle of the MOEMS SGM can reach 1 2. 2 ∘ . [ABSTRACT FROM AUTHOR]

This paper performs a detailed investigation on the electromagnetic angle sensor integrated in the flame retardant 4 (FR4)-based scanning micromirror. An accurate theoretical model is presented, especially considering the coupling effect between the driving and sensing coils. Experimental results agree well with the theoretical results, and show a sensitivity of 55.0 mVp/° and a high signal-to-noise ratio (SNR) of 71.9 dB. Moreover, the linearity of the angle sensor can still reach 0.9995, though it is affected slightly by the coupling effect. Finally, the sensor's good feasibility for feedback control has been further verified through a simple closed-loop control circuit. The micromirror operated with closed-loop control possesses better long-term stability and temperature stability than that operated without closed-loop control. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to investigate the changes in free amino acids (FAA) composition by supplementing three commercial proteases (Neutrase, Flavorzyme and Protamex) at the beginning of wort mashing, and monitoring the effects on the assimilation pattern of FAA and fermentation performance of lager yeast (Saccharomyces pastorianus) during normal and high gravity fermentations. Proteases supplementation significantly improved the extract yield and FAA level of mashed worts. Normal gravity worts treated with Flavorzyme and Neutrase exhibited higher fermentability, ethanol production and flavor volatiles concentration compared to the control worts, while these beneficial effects were observed in high gravity worts treated with Protamex and Neutrase. The reason for the above results is proposed to be the change in the assimilation pattern of FAA in lager yeast with increased wort gravity, especially for the improved assimilation ratios of Leu, Arg, Phe, His, Asp and Val. In normal gravity fermentations, there were strong correlations between the assimilation amounts of Lys, Leu, Arg and His and fermentability, while in high gravity fermentations, these good correlations were found with only Lys and His. The present study suggested that optimizing the composition of FAA by supplementing proteases during wort mashing was beneficial to beer brewing for improving fermentation performance of lager yeast and flavor volatiles formation. [Copyright &y& Elsevier]

The aim of this study was to evaluate the effects of lactic acid fermentation using three Lactobacillus strains (Lactiplantibacillus plantarum 90, Lactobacillus helveticus 76, and Lacticaseibacillus casei 37) in monoculture and binary mixture on phenolics profile, antioxidant activity and flavor volatiles in pear juice. Results showed that the colony counts of binary mixture were higher than monoculture in fermented pear juice. The total content of phenols was increased, while that of flavonoids was decreased significantly during fermentation (p < 0.05). Antioxidant activities in fermented peer juice including DPPH and ABTS radical scavenging abilities and ferric reducing antioxidant power (FRAP) were significantly improved (p < 0.05). Binary mixture of Lactiplantibacillus plantarum 90 and Lacticaseibacillus casei 37 fermentation exhibited strong DPPH radical scavenging ability, due to the increase in vanillic acid and arbutin contents. Furthermore, lactic acid fermentation improved the formation of alcohols, esters, acids and terpenoids, and reduced the contents of aldehydes and ketones. Thirty new compounds including 15 alcohols, seven esters, five acids, and three terpenoids were observed in fermented pear juice. Hierarchical cluster revealed that flavor volatiles in pear juice were improved dramatically by Lactobacillus strains fermentation, and there were dramatic differences between monoculture and binary mixture. [ABSTRACT FROM AUTHOR]

The effects of six commercial lactic acid bacteria (LAB) fermentation on bioactive phytochemicals, antioxidant activities and flavor profiles in Chinese wolfberry juice were investigated. All the strains exhibited satisfactory proliferative capacities in Chinese wolfberry juice with viable counts above 7 log CFU/mL at the end of fermentation. Bioactive phytochemicals were significantly increased by LAB, especially for Lactobacillus paracasei , Lactobacillus acidophilus and Bifidobacterium lactis increasing betaine from 8237.77 to ca. 20000 mg/L. Furthermore, antioxidant activities based on DPPH, ABTS and FRAP methods were significantly enhanced after LAB fermentation due to the accumulation of phenolics. In addition, 68 volatile compounds including 20 alcohols, 18 esters, 13 ketones, 10 aldehydes, three acids, three terpenes and theaspirane were detected. LAB fermentation resulted in significant decrease in aldehydes content and increase in esters production, suggesting that LAB could be employed to remove off-flavor and enrich pleasant flavor of Chinese wolfberry juice. [Display omitted] • Chinese wolfberry was a good substrate for proliferation of lactic acid bacteria. • Rutin and betaine levels were significantly increased by lactic acid fermentation. • Antioxidant activities were significantly improved by lactic acid fermentation. • Lactic acid fermentation decreased aldehydes level and increased esters production. [ABSTRACT FROM AUTHOR]

This paper presents a miniaturized, broadband near-infrared (NIR) spectrometer with a flame-retardant 4 (FR4)-based scanning micrograte. A 90° off-axis parabolic mirror and a crossed Czerny–Turner structure were used for creating an astigmatism-free optical system design. The optical system of the spectrometer consists of a 90° off-axis parabolic mirror, an FR4-based scanning micrograte, and a two-color indium gallium arsenide (InGaAs) diode with a crossed Czerny–Turner structure optical design. We used a wide exit slit and an off-axis parabolic mirror with a short focal length to improve the signal-to-noise ratio (SNR) of the full spectrum. We enabled a miniaturized design for the spectrometer by utilizing a novel FR4 micrograte for spectral dispersion and spatial scanning. The spectrometer can detect the full near-infrared spectrum while only using a two-color InGaAs diode, and thus, the grating scanning angle of this spectrometer is small when compared to a dual-detector-based spectrometer. In addition, the angle signal can be obtained through an angle sensor, which is integrated into the scanning micrograte. The real-time angle signal is used to form a closed-loop control over the scanning micrograte and calibrate the spectral signal. Finally, a series of tests was performed. The experimental results showed that the spectrometer has a working wavelength range of 800–2500 nm. The resolution is 10 nm at a wavelength range of 800–1650 nm and 15 nm at a wavelength range of 1650–2500 nm. Similarly, the stability of these two wavelength ranges is better than ±1 nm and ±2 nm, respectively. The spectrometer's volume is 80 × 75 × 65 mm3 and its weight is 0.5 kg. The maximum spectral fluctuation does not exceed 1.5% and the signal-to-noise ratio is 284 after only one instance of averaging. [ABSTRACT FROM AUTHOR]

This paper presents a compound control system for precise control of the flame-retardant 4 (FR4)-based electromagnetic scanning micrograting. It mainly consists of a frequency controller and an angle controller. A dual closed-loop structure consisting of a current loop and an angle loop was designed in the angle controller. In addition, the incremental proportional–integral–derivative (PID) control algorithm was designed in the current loop, and the fuzzy-PID control algorithm was employed in the angle loop. From the experimental results, the frequency controller can effectively track the real-time resonant frequency of the scanning micrograting with a tracking accuracy of 0.1 Hz. The overshoot of the scanning micrograting is eliminated. Compared to an open-loop control system, the control system presented in this work reduces the steady-state error of the scanning micrograting from 1.122% to 0.243%. The control accuracy of the compound control system is 0.02°. The anti-interference recovery time of the scanning micrograting was reduced from 550 ms to 181 ms, and the long-term stability was increased from 2.94% to 0.12%. In the compound control system presented in this paper, the crucial parameters of the FR4-based electromagnetic scanning micrograting, including motion accuracy, anti-interference ability, and long-term stability, were effectively improved. [ABSTRACT FROM AUTHOR]

This paper presents a flame retardant 4 (FR4)-based electromagnetic scanning micromirror, which aims to overcome the limitations of conventional microelectromechanical systems (MEMS) micromirrors for the large-aperture and low-frequency scanning applications. This micromirror is fabricated through a commercial printed circuit board (PCB) technology at a low cost and with a short process cycle, before an aluminum-coated silicon mirror plate with a large aperture is bonded on the FR4 platform to provide a high surface quality. In particular, an electromagnetic angle sensor is integrated to monitor the motion of the micromirror in real time. A prototype has been assembled and tested. The results show that the micromirror can reach the optical scan angle of 11.2° with a low driving voltage of only 425 mV at resonance (361.8 Hz). At the same time, the signal of the integrated angle sensor also shows good signal-to-noise ratio, linearity and sensitivity. Finally, the reliability of the FR4 based micro-mirror has been tested. The prototype successfully passes both shock and vibration tests. Furthermore, the results of the long-term mechanical cycling test (50 million cycles) suggest that the maximum variations of resonant frequency and scan angle are less than 0.3% and 6%, respectively. Therefore, this simple and robust micromirror has great potential in being useful in a number of optical microsystems, especially when large-aperture or low-frequency is required. [ABSTRACT FROM AUTHOR]

Wheat bran is an abundant source of cellulose and is still going to waste because of the lack of knowledge about its further exploitation and comprehensive utilisation. Here, cellulose nanocrystals (CNC) were prepared from wheat bran via sulfuric acid hydrolysis. The effects of hydrolysis time on the morphology, surface charge, yield, structure, thermal stability, physicochemical properties, and cytotoxicity of CNC were investigated. Results showed that non-cellulosic components were extensively removed by the purification process. Transmission electron microscopy confirmed that the obtained CNC displayed a needle-like shape with various dimensions. Zeta potential values of the CNC suspensions ranged from −36.5 to −39.8 mV. A hydrolysis time of 60 min resulted in CNC with the highest crystallinity (70.32%). The thermal stability of CNC shifted to lower temperature with increasing hydrolysis time. In addition, the obtained CNC exhibited interesting physicochemical properties (the water/oil retention capacities and the adsorption capacities to heavy metals) and good biocompatibility, suggesting their great potential as reinforcement for the manufacture of nanocomposites. • Cellulose nanocrystals (CNC) were successfully prepared from wheat bran. • The aspect ratio of CNC increased with acid hydrolysis time. • The water/oil retention capacities of CNC were investigated. • CNC exhibited excellent adsorption capacities to heavy metals. • CNC showed no obvious cytotoxicity to Caco-2 cells at 1000 μg/mL. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to isolate and identify antioxidant peptides from defatted walnut meal proteins hydrolysates (DWMPH) prepared by simulated gastrointestinal digestion, and to evaluate the protective effect of the selected antioxidant peptides against oxidative damage to SH-SY5Y cells. The DWMPH were purified by ultrafiltration, gel filtration chromatography and RP-HPLC successively, and finally six major peptides were identified as VRN, NPAN, AHSVGP, SSE, TY and SGGY by UPLC-QTOF-MS. TY and SGGY displayed stronger ABTS radical scavenging activity and higher ORAC value in comparison with other four peptides. Furthermore, 0.5 mg/mL SGGY exhibited significantly protective effect on SH-SY5Y cells against oxidative damage (p <.01). Therefore, it was suggested that walnut meal protein could serve as a potential source of antioxidative peptides through gastrointestinal digestion. Graphical abstract Unlabelled Image Highlights • Anti-oxidative peptides were prepared from walnut proteins by simulating gastrointestinal digestion. • Two peptides with excellent radical scavenging activity were identified. • SGGY exhibited excellent protective effect on SH-SY5Y cells against oxidative damage. [ABSTRACT FROM AUTHOR]

Although high gravity brewing technology has been widely used for beer industries due to its economic benefits, yeast cells are subjected to multiple environmental stresses throughout the fermentation process. Eleven bioactive dipeptides (LH, HH, AY, LY, IY, AH, PW, TY, HL, VY, FC) were selected to evaluate their effects on cell proliferation, cell membrane defense system, antioxidant defense system and intracellular protective agents of lager yeast against ethanol-oxidation cross-stress. Results showed that the multiple stresses tolerance and fermentation performance of lager yeast were enhanced by bioactive dipeptides. Cell membrane integrity was improved by bioactive dipeptides through altering the structure of macromolecular compounds of the cell membrane. Intracellular reactive oxygen species (ROS) accumulation was significantly decreased by bioactive dipeptides, especially for FC, decreasing by 33.1%, compared with the control. The decrease of ROS was closely related to the increase of mitochondrial membrane potential, intracellular antioxidant enzyme activities including superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), and glycerol level. In addition, bioactive dipeptides could regulate the expression of key genes (GPD1 , OLE1 , SOD2 , PEX11 , CTT1 , HSP12) to enhance the multilevel defense systems under ethanol-oxidation cross-stress. Therefore, bioactive dipeptides should be potentially efficient and feasible bioactive ingredients to improve the multiple stresses tolerance of lager yeast during high gravity fermentation. [Display omitted] • Bioactive dipeptides enhanced tolerance of yeast to ethanol-oxidation cross-stress. • Bioactive dipeptides improved yeast cell membrane integrity. • Bioactive dipeptides enhanced the antioxidant defense system of yeast. • Bioactive dipeptides promoted the accumulation of intracellular glycerol in yeast. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of Lactiplantibacillus plantarum (L. plantarum) fermentation and three types of vegetable oils (corn oil, peanut oil, and olive oil) supplementations on the physicochemical properties, bioactive components, and flavor volatiles of tomato pulp. Tomato pulp supplemented with oils was excellent food matrices for L. plantarum growth, and the colony counts remained above 8.3 log CFU/mL at the end of fermentation. The contents of total phenol, carotenoids and lycopene were dramatically increased after fermentation, and oils supplementation exhibited a synergistic promotion effect, especially for the combination of L. plantarum fermentation and 3% olive oil supplementation exhibiting the highest lycopene level (30 mg/mL), the strongest DPPH radical scavenging activity (84.24%) and FRAP (16.45 mmol Trolox/L). Furthermore, synergistic L. plantarum fermentation and oils supplementation decreased aldehydes content, and increased alcohols, esters, and ketones formation, meaning the improved flavor characteristics of fermented tomato pulp. In this study, a functional beverage of tomato pulp was prepared by the combination of L. plantarum fermentation and vegetable oils supplementation. Colony counts, lycopene level, antioxidant capacities, and flavor characteristics were dramatically improved at the end of fermentation. This study provides an innovative technology to improve the release of lycopene from plant tissue and provide a functional beverage of tomato pulp with high health benefits. [Display omitted] • Tomato pulps added with oils were good matrices for Lactiplantibacillus plantarum. • Combination of L. plantarum and oil promoted lycopene release from plant tissue. • Antioxidant capacity was improved by combination of L. plantarum and oil. • Esters and ketones formation was increased by combination of L. plantarum and oil. [ABSTRACT FROM AUTHOR]