EFFECT OF THERMAL PROCESSING ON THE PHENOLIC ASSOCIATED HEALTH-RELEVANT FUNCTIONALITY OF SELECTED LEGUME SPROUTS AND SEEDLINGS

The effect of thermal processing on modification of phenolics-linked functionality of the sprout and seedling extracts of select legumes was investigated. Health-relevant functionality for type 2 diabetes-related α-amylase and α-glucosidase inhibition, hypertension-related angiotensin-converting enzyme 1 (ACE 1) inhibition and ulcer-related Helicobacter pylori inhibition was investigated. Thermal processing via autoclaving resulted in tissue browning, leading to higher total phenolic content and free radical scavenging-linked antioxidant activity. Thermal processing also improved the type 2 diabetes-related functionality. Fenugreek had the highest α-amylase and α-glucosidase inhibitory activity, followed by soybean, fava bean and mung bean. The H. pylori inhibitory activity of all extracts improved substantially after thermal processing with direct correlation to phenolic content and related antioxidant activity. The ACE 1 inhibitory activity and levo-dihydroxy phenylalanine content of most extracts declined with thermal processing.

PRACTICAL APPLICATIONS

Thermal processing by autoclaving improved the total phenolic content and antioxidant activity in fava bean, mung bean, fenugreek, and soybean sprouts and seedlings. It improved diabetes-related α-amylase and α-glucosidase inhibitory activities and ulcer-related Helicobacter pylori inhibitory activity. It reduced the cognitive function-related levo-dihydroxy phenylalanine content and hypertension-related angiotensin-converting enzyme 1 inhibitory activity. Therefore, diet designs for chronic disease management will have to consider thermal processing-linked modification of bioactive ingredient profiles.     

Structure of Ferroelectric (Ba,Sr)TiO3 Thin Films for Tunable Microwave Devices

Ferroelectric (Ba,Sr)TiO₃ films have been deposited on (001) MgO single crystals by a pulsed laser deposition with oxygen background while heating the substrates. Deposited BST films exhibit epitaxial growth along (001), which are confirmed by x-ray diffraction measurement. Structure of (Ba,Sr)TiO₃ along in-plane and surface normal direction have been investigated and found to have a tetragonal distortion depend on the deposition conditions, such as oxygen pressure. Lattice parameter decreases with increasing oxygen pressure, and tetragonallity (c/a) changes from 1.005 to 0.997 as oxygen pressure increase. Interestingly, energy gap measured by FTIR decreases with decreasing oxygen pressure until it reach a certain oxygen pressure, then increases again with increasing oxygen pressure. Furthermore, microwave properties of devices measured by a HP 8510C vector network analyzer from 0.045–20 GHz suggest that the least distorted films exhibit a larger dielectric constant changes with dc bias field.     

Distribution of electric field for carbon nanotube assembly: Experiments (II)

The distribution effect of electric field on the alignment and attachment of carbon nanotubes (CNTs) were investigated. The experimental results were compared with the simulation results according to three different shaped electrodes. In previous simulation, the round shaped electrodes were expected to be more effective for aligning and attaching a single CNT between two electrodes than conical or rectangular shaped electrodes. To verify the simulation results, three different shaped electrodes were introduced and a single multi-walled carbon nanotube (MWNT) was attached. The optimal conditions for aligning and attaching MWNTs such as the frequency, applied voltage and concentration of MWNTs solution were investigated. Through repeated experiments, frequency of 100 kHz-10 MHz, applied voltage of 0.3-1.3 Vrms/μm, concentration of 5 μg/mL in MWNTs solution were obtained as a possible condition range to attach MWNTs. Under these conditions, the yield of MWNTs attachment between two electrodes was up to 70%. In previous simulation, furthermore, it was verified that the size of the stable or quasi-stable region made CNTs aligned and attached on different shaped electrodes from the comparison of the experimental and simulation results. Most single MWNT attachment was accomplished on the round shaped electrodes.     

Formation of nanocrystalline microstructure in arc ion plated CrN films

Applying negative bias voltages caused significant microstructure changes in arc ion plated CrN films. Nanocrystalline microstructures were obtained by adjusting the negative bias voltage. Structural characterizations of the films were carried out using X-ray diffractometry (XRD) and high-resolution transmission electron microscopy (HR-TEM). The results indicated that increasing ion bombardment by applying negative bias voltages resulted in the formation of defects in the CrN films, inducing microstructure evolution from micro-columnar to nanocrystalline. The microhardness and residual stresses of the films were also affected. Based on the experimental results, the evolution mechanisms of the film microstructure and properties were discussed by considering ion bombardment effects.     

不同负载条件下Al/Cu双层复合材料的界面特征(英文)

研究叠轧过程压下量对轧制Al/Cu双层板界面微观组织及力学性能的影响。采用透射电镜观察压下量为30%~65%时Al/Cu双层的界面微观组织。针对不同的界面组织,分别采用三点弯曲试验和剥离试验测试Al/Cu双层板的弯曲强度和连接强度。讨论了界面冶金接量对其连接强度的影响。结果表明,叠轧时随着压下量减小,Al/Cu双层板的弯曲强度、连接强度均降低,这主要与材料界面组织密切相关。三点弯曲试验也验证了这一点。     

Reduction of Salmonella Contamination on Chicken Egg Shells by a Peroxidase-Catalyzed Sanitizer

A peroxidase-catalyzed compound (PCC) sanitizer was tested to determine its bactericidal activity on Salmonella typhimurium and Salmonella enteritidis inoculated on egg shell surfaces. Eggs with no treatment were compared to those immersed in either deionized distilled water, PCC or 200 ppm chlorine-treated water for 1, 3 or 5 min. Eggs immersed in PCC or chlorinated water solutions had lower (P < 0.05) S. typhimurium and S. enteritidis populations than those not exposed to treatments. No differences were detected among PCC and chlorine treatments except the S. typhimurium populations from PCC dipped eggs were significantly higher than those from eggs dipped in the chlorinated water for 1 min. Results indicate that PCC has potential as an effective shell egg sanitizer.     

COMPARISON OF A PEROXIDASE-CATALYZED SANITIZER WITH OTHER EGG SANITIZERS USING A LABORATORY-SCALE SPRAYER

Microbial and foodborne pathogen contamination of eggs continues to represent an important public health concern. The goal of this study was to compare the efficacy of spraying shell eggs with PCC (peroxidase-catalyzed compound, Enzodine ^TM, Symbollon Corporation, Sudbury, MA) with that of other sanitizers in the reduction of surface microbial contamination using a laboratory-scale sprayer apparatus. Treatments were distilled-deionized water, PCC, chlorine (200 ppm), and quaternary ammonium (QA). Each egg was sprayed with 150 mL of the treatment over a 1 min period while being rotated at approximately 150 revolutions per min. Enumeration of aerobic plate populations indicated that all treatments (distilled-deionized water, chlorine, PCC, and QA) significantly reduced the viable aerobic bacterial populations and Salmonella typhimurium when compared to the nonsprayed dry egg control. Spraying eggs with PCC resulted in a 6 logarithmic reduction in viable S. typhimurium populations on egg shell surfaces. Unlike results found with aerobic bacterial populations, PCC was not as effective in reducing levels of S. typhimurium to the extent of the chlorine and QA treatments (greater than 6 logarithmic reduction) but greater than 3 logarithmic reduction was observed with PCC as compared to distilled-deionized water. This study suggests that PCC may be a viable alternative to chlorine and QA in the reduction of bacterial populations on shell egg surfaces and can be applied as a spray on egg shell surfaces.     

Optimization of Extrusion Rice Bran Stabilization Process

Effects of processing variables, production rate, number of die openings and initial moisture content on the discharge temperature and power input during rice bran extrusion with an autogenous single-screw extruder were analyzed. At extrusion temperatures above 128°C, all lipase activity in the bran was lost regardless of moisture content of the bran fed. Net specific energy input (NSE) varied with changes in die opening and moisture contents and total power efficiency was increased with increasing production rate without change in NSE value. Percolation rate through the extruded bran bed was increased to nine times over that of raw bran; the extraction time to reach 1% residual oil in extruded bran was reduced to 10 min from 100 min for the raw bran.