Advanced Materials Research Vols. 781-784

Abstract: Poly (hydroxyethyl methacrylate)-based composite cryogel with embedded macroporous cellulose beads (pHEMA-CB cryogel) could be of interest as chromatographic medium for bioseparation applications. In this work, liquid-solid phase transition characteristic of the suspension mixture containing HEMA, poly (ethylene glycol) diacrylate (PEGDA), ammonium persulfate (APS), N,N,N',N'-tetramethylethylenediamine (TEMED) and cellulose beads for the production of pHEMA-CB composite cryogel was investigated to reveal the solvent crystallization process occurring in the column. Freezing curves were obtained and the values of initial solvent crystallization temperature T_c and the freezing point temperature T_mc were estimated. Protein binding property of the pHEMA-CB cryogel grafted with (vinylbenzyl) trimethylammonium chloride (VBTAC) was measured and discussed.

Abstract: A quick and accurate HPLC method has been developed for the simultaneous quantification of two bioactive triterpenes, ursolic acid and oleanolic acid in Paulownia leaves. The samples were analyzed on a Shim-pack ODS-CLC (M) (4.6 mm × 250 mm, 5 μm) column kept at 21 °C, using the methanol and aqueous phase containing 0.05%phosphoric acid with the volumetric ratio of 91.7:8.3 as the mobile phase at a flow rate of 0.6 mL/ min, and the detection wavelength was set at 210 nm. The method was validated and applied to the simultaneous quantification of the two triterpenes in Paulownia leaf extract. The standard curves were established in the range of 0.44 ~ 8.75 μg for oleanolic acid and 0.92 ~ 18.37 μg for ursolic acid. The contents of oleanolic acid and ursolic acid in leaves of Paulownia were determinated using the HPLC method and the contents were 3.87 mg/g and 13.61 mg/g, respectively.

Abstract: The preparation, approximate composition, degree of hydrolysis (DH), lipase activity and antioxidant capacity (including the ability of scavenging DPPH and ABTS free radicals) were determined for various of aqueous enzymatic extract (AEE) obtained from rice bran (RB) using alcalase (A), trypsin (T), papain (Pn), neutrase (N) and protamex (Px). Peptides and γ-oryzanol are the major functional components of AEE. Generally, the protein yield varied with the type of enzyme used in the order of T>Pn>N>Px>A. Both trypsin and alcalase extracts exhibit a higher level of γ-oryzanol than other enzymes. Lipase activity was measured using the 4-Nitrophenyl Laurate (p-NPL) substrate method, and significantly different (P<0.05) lipase activity values ranging from 0.55 to 2.38 mU/mL were observed from five hydrolysates. Furthermore, two synthetic free radicals were used to evaluate the antioxidant activity of AEE. The alcalase extract (at 4.35±0.15mg protein/mL AEE) shows the greatest scavenging rate (28.42%) of DPPH, but trypsin extract has highest ABTS radical-scavenging activity of 94.05%. Data revealed trypsin was possible the most effective extractant under their optimal conditions. These results demonstrate that the product obtained from rice bran by different enzymatic digestions may contain bioactive components and might potentially be natural antioxidants. Meanwhile, the aqueous enzymatic extraction method can also improve the stability of the hydrolysates.

Abstract: Poisson's ratio is one of the important physical parameters in the finite element calculation model of corn kernel. In this study, through the preparation of the test material and test program design, with the loading speed of the testing machine was 2mm/min, through applied different loading (30N, 90N, 120N and 150N) for Poisson's ratio determination about corn kernel with the experiment. The test results showed that the Poisson's ratio average value in 0.399-0.423 when the corn kernel moisture content was 13.2%, the greater loading was applied, and the smaller value in the fluctuation range of the Poisson's ratio was measured. When applied to the indenter loading of 150N, the corn kernel Poisson ratio fluctuation which was between the minimum and maximum value of 5.1%.

Abstract: Fast temperature-responsive interpenetrating polymer network hydrogels based on soy protein and poly(N-isopropylacrylamide) (PNIPAAm) were prepared using the sodium bicarbonate (NaHCO₃) solutions as the reaction medium. The structure and properties were characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The bovine serum albumin (BSA) release behaviors and release mechanism were also investigated. The results show that the proposed hydrogels have high porous structures and have a fast release rate. The BSA release mechanism belongs to an anomalous transport and the Fickian contribution is dominant. The proposed hydrogels may have the potential applications in the field of biomedical materials such as in the controlled release of drugs.

Abstract: Protoplast technique is a powerful tool for strain improvement and the preparation of protoplasts with high regeneration efficiency is the basis of subsequent manipulations. In this study, the effects of enzymatic hydrolysis time on release and regeneration of protoplasts from Aspergillus oryzae HN3042 were investigated by analyzing the time-series image. The results showed that there was a significant correlationship between regeneration efficiency and morphological size of protoplasts (P < 0.01). An efficient method for monitoring and improving the regeneration efficiency of protoplast was thus established by controlling the enzymatic hydrolysis process and the results can be referred to other species during the preparation and regeneration of protoplasts.

Abstract: Paraoxonase (PON) is a hydrolyase correlated with many chronic diseases. The use of 9-(4-chlorophenyloxycarbonyl)-10-methylacridinium triflate ester (CPOCMA) as a substrate for determination of serum arylesterase PON activity had been reported. It is meaningful to compare this substrate with phenyl acetate further with serum samples of patients with coronary heart disease (CHD, n=104). Correlations of PON arylesterase activity with CHD and also with age were analyzed. There was no significant difference in serum arylesterase activity (based on the CPOCMA or the phenyl acetate) between of the CHD inpatients and controls at same age level (45-60 years old). Statistically negative correlation of serum PON CPOCMAase activity (p=0.020) but not the activity based on phenyl acetate (p>0.05) with age was observed. Based on the both substrates, significant decrease in PON activity was found in the old CHD inpatients (≥60 years old), compared with that in the young CHD inpatients (<60 years old), or with that in the young controls. The methods based on CPOCMA substrate and based on the phenyl acetate demonstrated consistent results in correlation with CHD, but different results in correlation of PON activity with age.

Abstract: The tocopherols in Rhodiola sachalinensis were determined with adsorption column chromatographic purification and GC/MS. Tocopherols were extracted by sonication and Soxhlet with ethanol and dichloromethane, respectively. The extract was partitioned with chloroform and water using liquid-liquid extraction, and water part was partitioned with ethyl acetate, and purified with a silica column. Three type of tocopherols such as α, β, γ-tocopherol were identificated from Rhodiola sachalinensis by GC/MS. All of the three types of tocopherols were determined in the chloroform part, with some sterol and sterol conjugates. The similarities of the three types of tocopherols were nearly or above 90%, and the retention time of α, β, γ-tocopherols were 24.085, 23.194, and 22.458min, respectively.

Abstract: Beet necrotic yellow vein virus coat protein (BNYVV CP) gene cloned from BNYVV in Inner Mongolia of China was transferred to sugar beet explants using agrobacterium tumefaciens-mediated method. Transgenic regeneration shoots were induced from petioles and cotyledons tissues of sugar beet. Three sugar beet lines that were fit for genetic transformation experiment were screened, which were Sumfull8-1, Sumfull8-3 and 9718. The experiment results showed that plant regeneration frequency was influenced by many factors, which include hormone compositions and concentration in shoots regeneration medium, culture conditions, sugar beet genotype, original explant types and culture methods. Influence factors of transgenic shoot regeneration frequency for sugar beet explants were discussed in this paper. Efficient genetic transformation system and transgenic shoots regeneration system of sugar beet were established.

Abstract: Substances from Fructus Alpinia Oxyphylla (AOF) were extracted by using solvent extraction. In accordance with central composited design of response surface methodology system, the extracts were analyzed for the index which is the criteria formula of multiplying OD value by the yield. The optimum conditions obtained were extraction temperature of 60°C, liquid-solid ratio of 9mL/g, and solvent density of 80%. According to Ficks second law of diffusion, experimental parameters of K (rate constant), Ea (activation energy), Gs (effective diffusion coefficient) were gained, which represents a good agreement between the model simulation and the results of the actual process. The results can provide the valuable theory basis for the technical design and further research of extraction process. Antibacterial activities of the extraction were shown through MIC of which represents a significant effect.