scholarly journals Preparation of Heat-Sensitivity Proteins from Walnut Meal by Sweep Frequency Ultrasound-Assisted Alkali Extraction

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Wenjuan Qu ◽  
Wei Fan ◽  
Yiting Feng ◽  
Yunliang Li ◽  
Haile Ma ◽  
...  
Keyword(s):  
Structural Changes ◽  
Ph Value ◽  
Structural Characteristics ◽  
Duty Ratio ◽  
Heat Sensitivity ◽  
Ultrasonic Frequency ◽  
Sweep Frequency ◽  
Alkali Extraction ◽  
Ultrasonic Time ◽  
Frequency Ultrasound

Sweep frequency ultrasound- (SFU-) assisted alkali extraction was conducted to increase the yield and content of heat-sensitive protein of walnut meal under a relatively mild condition. The physicochemical and structural characteristics of the proteins obtained by SFU-assisted alkali extraction and the conventional alkali extraction were compared. It was found that the optimal parameters for the SFU-assisted extraction were the solid-liquid ratio of 1 : 12, pH value of 9, initial temperature of 25°C, ultrasonic frequency of 28 kHz, sweep frequency amplitude of 1.5 kHz, sweep frequency cycle of 100 ms, duty ratio of 77%, and ultrasonic time of 90 min. Under this condition, a vast improvement in the walnut protein yield (34.9%) and the walnut protein content (9.8%) was observed. Such improvement was due to the structural changes of the sonicated protein; e.g., SFU decreased the intermolecular/intramolecular hydrogen bond force of proteins and, therefore, caused more order secondary structures and more loosen microstructures. This helped to improve the thermoplastic and solubility of the heat-sensitivity protein. Thus, SFU treatment could be an effective auxiliary technology in the alkali extraction of heat-sensitivity walnut protein. It might also be a promising technology for the extraction of heat-sensitivity protein from other agricultural by-products.

scholarly journals Effects of Different Working Modes of Ultrasound on Structural Characteristics of Zein and ACE Inhibitory Activity of Hydrolysates

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaofeng Ren ◽  
Xi Zhang ◽  
Qiufang Liang ◽  
Ting Hou ◽  
Huiji Zhou
Keyword(s):  
Inhibitory Activity ◽  
Fluorescence Spectra ◽  
Structural Changes ◽  
Structural Characteristics ◽  
Intrinsic Fluorescence ◽  
Cd Spectra ◽  
Fixed Frequency ◽  
Ace Inhibitory Activity ◽  
Ace Inhibitory ◽  
Frequency Ultrasound

Ultrasound was used as a new technology to pretreat protein prior to proteolysis to improve enzymolysis efficiency. The effects of different working modes of ultrasound on the angiotensin I-converting enzyme (ACE) inhibitory activity of zein hydrolysates and the structural characteristics of zein were investigated. The solubility, surface hydrophobicity (H0), ultraviolet-visible (UV-Vis) spectra, intrinsic fluorescence spectra, and circular dichroism (CD) spectra of zein pretreated with ultrasound were determined. All ultrasound pretreatments significantly improved the ACE inhibitory activity of zein hydrolysates (p<0.05). The highest ACE inhibitory activity, representing an increase of 99.21% over the control, was obtained with dual sweeping frequency ultrasound of 33±2 and 68±2 kHz. The effects of single sweeping frequency and dual fixed frequency ultrasound were stronger than those of single fixed frequency ultrasound for improving the ACE inhibitory activity of zein. Structural changes in zein were induced by ultrasound, as confirmed by changes in the solubility, H0, UV-Vis spectra, intrinsic fluorescence spectra, and CD spectra of zein, and these were consistent with the corresponding ACE inhibitory activities of zein hydrolysates. Thus, ultrasound working mode and frequency have significant effects on the structure of zein and the ACE inhibitory activity of zein hydrolysates.

The Application of Ultrasonic Instead of Sulfur Dioxide in Processing of Strawberry Wine

2013 ◽  
Vol 634-638 ◽  
pp. 1157-1164 ◽  
Author(s):  
Ming Zhu Jiang ◽  
Wen Bo Wang ◽  
Yan Mei Wei ◽  
Yong Kun Ma
Keyword(s):  
Sulfur Dioxide ◽  
Sensory Evaluation ◽  
Ph Value ◽  
Ultrasonic Frequency ◽  
Ultrasonic Power ◽  
Total Acidity ◽  
Sensory Score ◽  
Ultrasonic Time ◽  
The Impact

Using fresh strawberry fruits as materials, the impact of using ultrasound to sterilize the process of strawberry wine was studied in this paper. In the experiment, the effects of different ultrasonic frequency, ultrasonic time and ultrasonic temperature in processing of strawberry wine were studied respectively. The results indicated that the treatment with supersonic procession of 40°C, 60min and 120W could get the best pH value of strawberry wine; the treatment with supersonic procession of 40°C, 45min, 80W could get the best total acidity value; the treatment with supersonic procession of 30°C, 45min, 120W could get the best Vc content value; the treatment with supersonic procession of 40°C, 45min, 100W could get the best sensory score of strawberry wine; treated with supersonic procession of 40°C, 30min, 100W, the microbic quantity of strawberry wine could be get the lowest value. Among them, ultrasonic power had a more significant effect on the pH and total acidity of strawberry wine, as well as ultrasonic temperature on the content of Vc and ultrasonic time on the sensory evaluation and microbial quantity.

Research on Bleaching Processes of Natural Cane Fiber by Ultrasonic

2012 ◽  
Vol 550-553 ◽  
pp. 565-568
Author(s):  
Zhen Xu Sun ◽  
Yu Ping Zhao ◽  
Ruo Yuan Song ◽  
Yong Fang Qian
Keyword(s):  
Ph Value ◽  
Processing Parameters ◽  
Ultrasonic Frequency ◽  
Single Factor ◽  
Bleaching Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ultrasonic Time ◽  
Single Factor Experiment ◽  
Scanning Electron

The effects of ultrasonic on bleaching of cane fiber were discussed in this paper. Ultrasonic frequency, ultrasonic time, the concentration of the hydrogen peroxide, temperature and pH value were optimized by the single factor experiment. The bleached fiber was analyzed by X-ray diffraction and Scanning electron microscope. The results showed the optimum processing parameters as follows: ultrasonic time 40 min, ultrasonic frequency 33 KHz (first 20 min); 55 KHz (second 20 min), temperature 90°C and the concentration of the hydrogen 30 ml/L, pH value 10.5. In the above conditions, the best bleaching effect was achieved.

scholarly journals Unraveling a Force-Generating Allosteric Pathway of Actomyosin Communication Associated with ADP and Pi Release

2020 ◽  
Vol 22 (1) ◽  
pp. 104
Author(s):  
Peter Franz ◽  
Wiebke Ewert ◽  
Matthias Preller ◽  
Georgios Tsiavaliaris
Keyword(s):  
Structural Changes ◽  
Atp Hydrolysis ◽  
Power Stroke ◽  
Duty Ratio ◽  
Prolonged Duration ◽  
Adp Release ◽  
Strong Transition ◽  
Cleft Closure ◽  
Kinetic Investigations ◽  
Allosteric Pathway

The actomyosin system generates mechanical work with the execution of the power stroke, an ATP-driven, two-step rotational swing of the myosin-neck that occurs post ATP hydrolysis during the transition from weakly to strongly actin-bound myosin states concomitant with Pi release and prior to ADP dissociation. The activating role of actin on product release and force generation is well documented; however, the communication paths associated with weak-to-strong transitions are poorly characterized. With the aid of mutant analyses based on kinetic investigations and simulations, we identified the W-helix as an important hub coupling the structural changes of switch elements during ATP hydrolysis to temporally controlled interactions with actin that are passed to the central transducer and converter. Disturbing the W-helix/transducer pathway increased actin-activated ATP turnover and reduced motor performance as a consequence of prolonged duration of the strongly actin-attached states. Actin-triggered Pi release was accelerated, while ADP release considerably decelerated, both limiting maximum ATPase, thus transforming myosin-2 into a high-duty-ratio motor. This kinetic signature of the mutant allowed us to define the fractional occupancies of intermediate states during the ATPase cycle providing evidence that myosin populates a cleft-closure state of strong actin interaction during the weak-to-strong transition with bound hydrolysis products before accomplishing the power stroke.

scholarly journals Optimization of Ultrasonic-Assisted Extraction, Characterization, and Antioxidant Activities of Polysaccharides From Sojae Semen Praeparatum

2021 ◽  
Vol 16 (5) ◽  
pp. 1934578X2110206
Author(s):  
Yongshuai Jing ◽  
Ruijuan Zhang ◽  
Lan Li ◽  
Danshen Zhang ◽  
Yu Liu ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Deae Cellulose ◽  
Chemical Compositions ◽  
Hydroxyl Groups ◽  
Ultrasonic Frequency ◽  
Ultrasonic Power ◽  
Assisted Extraction ◽  
Ultrasonic Time ◽  
Ultrasonic Assisted ◽  
Ultrasonic Assisted Extraction

In this study, response surface methodology (RSM) was used to optimize the ultrasonic-assisted extraction parameters of Sojae Semen Praeparatum polysaccharides (SSPP-80), the optimum conditions were determined as follows: ultrasonic frequency of 100 W, ultrasonic power of 80 Hz, ultrasonic temperature of 52℃, ultrasonic time of 23 minutes, and liquid to raw material ratio of 40 mL/g. Based on these conditions, polysaccharides extraction rate was 7.72% ± 0.26%. Then, 2 novel polysaccharides (SSPP-80‐1, SSPP-80‐2) were isolated from SSPP by DEAE-cellulose 52 chromatography. The chemical compositions, physicochemical properties, and structure of SSPPs were investigated by simultaneous thermal analyzer (TGA), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FI-IR), and high-performance liquid chromatography (HPLC). The results showed that SSPP-80 and 2 fractions were mainly composed of mannose (Man), glucose (Glc), galactose (Gal), xylose (Xyl), and arabinose (Ara). In addition, the antioxidant activities were evaluated against the DPPH and hydroxyl radical in vitro, the IC50 of SSPP-80, SSPP-80‐1 and SSPP-80‐2 against DPPH free radical were 4.407, 8.267, and 5.204 mg/mL, respectively, whereas the IC50values for removing hydroxyl groups were 5.318, 3.516, and 4.016 mg/mL, respectively. It demonstrated that SSPP-80 and 2 fractions had certain antioxidant activity. Theoretical basis for use of Sojae Semen Praeparatum polysaccharides was provided by this study.

Study of Properties of Expanded Graphite – Polymer Porous Composite by Acoustic Emission Method

2013 ◽  
Vol 58 (4) ◽  
pp. 1331-1336 ◽  
Author(s):  
J. Berdowski ◽  
S. Berdowska ◽  
F. Aubry
Keyword(s):  
Acoustic Emission ◽  
Structural Changes ◽  
Structural Characteristics ◽  
Physical And Mechanical Properties ◽  
Expanded Graphite ◽  
Composite Membranes ◽  
Acoustic Emission Method ◽  
Emission Method ◽  
Graphite Composite ◽  
Wide Range

Abstract The purpose of this paper was to investigate the physical and mechanical properties of compressed expanded graphite (CEG) and their porous derivatives after impregnation, polymerization; and carbonization by the use of acoustic emission method (AE). The mechanical and structural characteristics of compressed expanded graphite and their three groups of porous composites after each technological process are presented and discussed. The measurements of acoustic emission parameters in these materials were carried out at wide range of frequency of the waves (0.1÷2.5 MHz). The changes of two of parameters: - AE pulses counts rate and spectrum distribution of AE waves - are presented in this paper. The analysis of the respective parameters AE also gives possibility to determine the micro- and macro structural changes of materials at different levels of technological processes. Applications of these materials as catalysts with high specific surface make them very interesting subject of study. Also compressed expanded graphite composite membranes prepared from furfuryl alcohol polymers are promising for gas separation.

The structure and changes of China’s land system

2019 ◽  
Vol 11 (3) ◽  
pp. 471-488 ◽  
Author(s):  
Liu Shouying
Keyword(s):  
Economic Growth ◽  
Institutional Change ◽  
Structural Changes ◽  
Structural Characteristics ◽  
Institutional Arrangements ◽  
Reform Process ◽  
Content Type ◽  
The Past ◽  
Land System ◽  
Rapid Economic Growth

Purpose The purpose of this paper is to analyze the structure and changes of China’s land system. To achieve this aim, the paper is divided into four parts. The first part gives a brief introduction to the structural characteristics of the Chinese land institutional arrangements; the second part analyzes the reform process of the land system in the past 40 years and its path of change; the third part engages the discussion about the historic contribution made by the land institutional change to rapid economic growth and structural changes; and the final part is conclusion and some policy implications. Design/methodology/approach After 40 years of reforms and opening up, China has not only created a growth miracle unparalleled for any major country in human history, but also transformed itself from a rural to an urban society. Behind this great transformation is a systemic reform in land institutions. Rural land institutions went from collectively owned to household responsibility system, thereby protecting farmers’ land rights. This process resulted in long-term sustainable growth in China’s agriculture, a massive rural-urban migration and a historical agricultural transformation. The conversion of agricultural land to non-agricultural uses and the introduction of market mechanisms made land a policy tool in driving high economic growth, industrialization and urbanization. Findings Research shows that the role of land and its relationship with the economy will inevitably change as China’s economy enters a new stage of medium-to-high speed growth. With economic restructuring, low-cost industrial land will be less effective. Urbanization is also shifting from rapid expansion to endogenous growth so that returns on land capitalization will decrease and risks will increase. Therefore, China must abandon land-dependent growth model through deepening land reforms and adapt a new pattern of economic development. Originality/value This paper gives a brief introduction to the structural characteristics of the Chinese land institutional arrangements, analyzes the reform process of the land system in the past 40 years and its path of change, and evaluates the historic contribution made by the land institutional change to rapid economic growth and structural changes.

Study on the Dispersion of Carbon Doped Titanium Dioxide Powder in Aqueous Solution

2013 ◽  
Vol 788 ◽  
pp. 246-249 ◽  
Author(s):  
Zhi Wang ◽  
Zhi Qiang Yang
Keyword(s):  
Aqueous Solution ◽  
Titanium Dioxide ◽  
Ph Value ◽  
Mass Ratio ◽  
Carbon Doped ◽  
Titanium Dioxide Powder ◽  
Dioxide Powder ◽  
Ultrasonic Time ◽  
Dispersant Additive ◽  
Doped Titanium Dioxide

The dispersion of carbon doped titanium dioxide (TiO2) powder in aqueous solution was studied. The spectrophotometer method was used to determine the effects of dispersant additive ratio, ultrasonic time and pH value on the dispersion of TiO2. The results show that the carbon doped titanium dioxide aqueous solution was found to have the optimum dispersion performance when the mass ratio of sodium hexametaphosphate (SHMP)/TiO2/water is 1:50:100, the ultrasonic time is 15min and the pH value of the solution is 10.

scholarly journals Investigation of the Structural Changes and Catalytic Properties of FeNi Nanostructures as a Result of Exposure to Gamma Radiation

Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 254
Author(s):  
Daryn B. Borgekov ◽  
Maxim V. Zdorovets ◽  
Dmitriy I. Shlimas ◽  
Artem L. Kozlovskiy
Keyword(s):  
Gamma Radiation ◽  
Point Defects ◽  
Gamma Rays ◽  
Structural Changes ◽  
Catalytic Properties ◽  
Structural Characteristics ◽  
Catalytic Reactions ◽  
Radiation Doses ◽  
Crystallite Orientation ◽  
Complete Destruction

The paper presents the results of changes in the structural characteristics, and the degree of texturing of FeNi nanostructures close in composition to permalloy compounds as a result of directed modification by gamma radiation with an energy of 1.35 MeV and doses from 100 to 500 kGy. The choices of energy and radiation doses were due to the need to modify the structural properties, which consisted of annealing the point defects that occurred during the synthesis along the entire length of the nanotubes. The initial FeNi nanostructures were polycrystalline nanotubes of anisotropic crystallite orientation, obtained by electrochemical deposition. The study found that exposure to gamma rays led to fewer defects in the structure, and reorientation of crystallites, and at doses above 300 kGy, the presence of one selected texture direction (111) in the structure. During tests of the corrosion resistance of synthesized and modified nanostructures in a PBS solution at various temperatures, it was found that exposure to gamma rays led to a significant decrease in the rate of degradation of nanotubes and an increase in the potential life of up to 20 days. It was established that at the first stage of testing, the degradation of nanostructures is accompanied by the formation of oxide inclusions, which subsequently lead to the formation of pitting corrosion and subsequent partial or complete destruction of the nanostructures. It is shown that gamma radiation is promising not only for targeted modification of nanostructures and increasing resistance to degradation, but also for increasing the rate of catalytic reactions of the PNA-PPD type.

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