Antioxidant peptides have been widely reported.However,only a few reports have been published examining the antioxidant peptides derived from Chinese baijiu.In this study,6 novel peptides derived from Chinese baijiu w...Antioxidant peptides have been widely reported.However,only a few reports have been published examining the antioxidant peptides derived from Chinese baijiu.In this study,6 novel peptides derived from Chinese baijiu were identified successfully using high-performance liquid chromatography-quadrupoletime-of-flight mass spectrometry(HPLC-QTOF-MS)with a concentration of 0.835–24.540μg/L.The underlying molecular mechanisms were investigated,and their cytoprotective effects were examined against 2,2’-azobis(2-methylpropanimidamidine)dihydrochloride(AAPH)-induced oxidative stress in Hep G2 cells.The results showed that these peptides exerted protective effects by suppressing reactive oxygen species(ROS)generation,preventing malondialdehyde(MDA)formation,and upregulating cellular antioxidant enzyme activities(SOD,CAT,and GSH-Px)in a dose-dependent manner.Further experiments proved that these peptides exerted antioxidant effects via Nrf2/ARE-mediated signaling pathway by promoting Nrf2 nuclear translocation,inhibiting ubiquitination,and enhancing transcription capacity of Nrf2 in Hep G2 cells.These findings provide the molecular basis for the effects of antioxidant peptides derived from Chinese baijiu,which is important for a deeper understanding of the relationship between human health and moderate drinking.展开更多
The dynamic characteristics of flow field in cyclone separators with different dust hopper structures were studied by coupling Reynolds Stress Model(RSM)and Lagrangian Particle Tracking(LPT)methods.The characteristic ...The dynamic characteristics of flow field in cyclone separators with different dust hopper structures were studied by coupling Reynolds Stress Model(RSM)and Lagrangian Particle Tracking(LPT)methods.The characteristic frequencies of cylinder section,cone section and dust hopper were calculated as f_(1)=53 Hz,f_(2)=65 Hz,and f_(3)=8 Hz by using Fast Fourier Transform(FFT)method,respectively.Based on the effects of f3 on the motion of vortex,the separated space was divided into none affected region,weakly affected region,and strongly affected region.The characteristic frequency of dust hopper increased with the decrease of dust hopper diameter,while it was independent of the height.The dust hopper with d=1.5D(model D3)and h=1.5D(model H3)can significantly decrease the effect of back-mixing on the motion of inner vortex,which is beneficial to improve the efficiency of cyclone separator.展开更多
A90°elbow equipped with guide vanes was developed with the intent of reducing elbow erosion.Numerical models were formed to predict the maximum erosion rate of elbow and Face-1,and the response surface methodolog...A90°elbow equipped with guide vanes was developed with the intent of reducing elbow erosion.Numerical models were formed to predict the maximum erosion rate of elbow and Face-1,and the response surface methodology was used to study the relationship between the erosion rate and structural parameters of guide vane.A second-order response surface model was established to determine the relationship between R and variables,and a reduced cubic(RC)polynomial model was obtained to reveal the relation-ship between R2 and the three factors.The numerical results show that the low-speed region is expended and the maximum discrete particle matter(DPM)concentration is reduced after installing the guide vane.This internal component provides a shelter for the elbow from the direct impact of high-speed solids.展开更多
基金supported by National Key Research&Development Program of China(2017YFC1600401-3)National Natural Science Foundation of China(31871749 and 31701567)。
文摘Antioxidant peptides have been widely reported.However,only a few reports have been published examining the antioxidant peptides derived from Chinese baijiu.In this study,6 novel peptides derived from Chinese baijiu were identified successfully using high-performance liquid chromatography-quadrupoletime-of-flight mass spectrometry(HPLC-QTOF-MS)with a concentration of 0.835–24.540μg/L.The underlying molecular mechanisms were investigated,and their cytoprotective effects were examined against 2,2’-azobis(2-methylpropanimidamidine)dihydrochloride(AAPH)-induced oxidative stress in Hep G2 cells.The results showed that these peptides exerted protective effects by suppressing reactive oxygen species(ROS)generation,preventing malondialdehyde(MDA)formation,and upregulating cellular antioxidant enzyme activities(SOD,CAT,and GSH-Px)in a dose-dependent manner.Further experiments proved that these peptides exerted antioxidant effects via Nrf2/ARE-mediated signaling pathway by promoting Nrf2 nuclear translocation,inhibiting ubiquitination,and enhancing transcription capacity of Nrf2 in Hep G2 cells.These findings provide the molecular basis for the effects of antioxidant peptides derived from Chinese baijiu,which is important for a deeper understanding of the relationship between human health and moderate drinking.
基金gratefully acknowledge the support from the Fundamental Research Funds for the Central Universities/the Development Fund of State Key Laboratory of Heavy Oil Processing(grant No.20CX02215A)the Natural Science Foundation of Shandong Province(grant No.ZR2021ME036)the National Natural Science Foundation of China(grant No.51806248).
文摘The dynamic characteristics of flow field in cyclone separators with different dust hopper structures were studied by coupling Reynolds Stress Model(RSM)and Lagrangian Particle Tracking(LPT)methods.The characteristic frequencies of cylinder section,cone section and dust hopper were calculated as f_(1)=53 Hz,f_(2)=65 Hz,and f_(3)=8 Hz by using Fast Fourier Transform(FFT)method,respectively.Based on the effects of f3 on the motion of vortex,the separated space was divided into none affected region,weakly affected region,and strongly affected region.The characteristic frequency of dust hopper increased with the decrease of dust hopper diameter,while it was independent of the height.The dust hopper with d=1.5D(model D3)and h=1.5D(model H3)can significantly decrease the effect of back-mixing on the motion of inner vortex,which is beneficial to improve the efficiency of cyclone separator.
基金The authors gratefully acknowledge the financial supports by the National Youth Foundation of China(51806248)Natural Science Foundation of Shandong Province(ZR2018BB068)and Innovation Project for Postgraduate of UPC(20CX02215A).
文摘A90°elbow equipped with guide vanes was developed with the intent of reducing elbow erosion.Numerical models were formed to predict the maximum erosion rate of elbow and Face-1,and the response surface methodology was used to study the relationship between the erosion rate and structural parameters of guide vane.A second-order response surface model was established to determine the relationship between R and variables,and a reduced cubic(RC)polynomial model was obtained to reveal the relation-ship between R2 and the three factors.The numerical results show that the low-speed region is expended and the maximum discrete particle matter(DPM)concentration is reduced after installing the guide vane.This internal component provides a shelter for the elbow from the direct impact of high-speed solids.
