• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.987-997
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• 2015

Schisandra chinensis (Sc), a species of the family Schisandraceae used fruits as medicinal herbs. In the study, we performed to determine a comparison of antioxidant activity from Sc water extracts depending on stir-frying and stir-frying with liquids by 30% ethanol pretreatments. The contents of polyphenol and flavonoid, DPPH radical scavenging, ABTS radical scavenging and reducing power activity were measured to evaluate the antioxidant activity. Total polyphenol and flavonoid contents of Sc extracts were increased in stir-frying and 30% ethanol stir-frying pretreatments compared to a control. In particular, contents of stir-frying pretreatments Sc were highest increased at $220^{\circ}C$ treatments. The DPPH radical scavenging activity were highest increased in stir-frying pretreatments at $220^{\circ}C$. And result that measurement of the ABTS radical scavenging, it showed higher activity in 30% ethanol stir-frying pretreatments at $180^{\circ}C$ and $220^{\circ}C$. But Sc in the $140^{\circ}C$ showed higher activity in stir-frying pretreatments. In the reducing power activity, stir-frying pretreatments increased higher than 30% ethanol stir-frying pretreatments at $220^{\circ}C$. As in results, antioxidant activity of Sc water extracts in stir-frying and stir-frying with liquids process increased higher than a control, and it was most effectively in stir-frying pretreatments at $220^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.144-149
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• 2004

Changes in functional constituents of grape (Vitis vinifera) seeds prepared by three different heat pretreatments were determined and compared with those of non-treated grape seed. The recovery of grape seed oils was generally increased by roasting, steaming and microwave processes, although the recovery of specific constituents varied among three heat pretreatments. The recovery of MeOH extracts of the seeds increased following the roasting process, whereas that of MeOH extracts decreased gradually with steaming and microwave treatments. Levels of four catechins in grape seeds: (+)-catechin, procyanidin B$_2$, (-)-epicatechin, and (-)-epicatechin gallate, were decreased with increased roasting and steaming time, but were unaffected by microwave treatment. During the three different heat pretreatments, levels and compositions of fatty acid did not change, whereas those of phytosterol compositions decreased greatly. These results suggest that a mild heat pretreatment, controlled for temperature and time, is needed to prevent a considerable loss in the level of valuable functional components in grape seed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.4
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• pp.221-224
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• 2002

Biomass of non-viable and dried brown marine algae Ecklonia radiata Turn. was used to examine Its cadmium uptake capability. Twelve different pretreatments on the algal biomass were prepared. Among these pretreatments, the algal biomass, which treated with 0.1 M NaOH and kept in water. bath (100$\^{C}$, 18 h) followed by washing with distilled water and squeezing, showed the highest amount of cadmium uptake as 1634 $\pm$ 195 mg/g dry biomass at pH 4.0 and 50$\^{C}$. Adsorption temperatures and pH levels played some Important role In cadmium uptake. However, cadmium uptake decreased dramatically at a lower pH than 4.0. Freundlich adsorption isotherm showed potent cadmium uptake capacity of the non-viable biomass. Pretreatments on the non-viable algal biomass shown in this study nay enhance the Eadmium removal in the industrial wastewater.

• Journal of the Korean Wood Science and Technology
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• v.22 no.4
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• pp.7-12
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• 1994

In recent years, the municipal wastes recognized resources. This study was performed to survey the changes of main components of the pretreated(chemical, physical) lignocellulosic biomass. The result can be summerized as follows; In pulp fiber composition, newsprint and corrugating container were mainly consist of softwood fiber(tracheid). But computer print out and magazine had a large amount of hardwood fiber(wood fiber). And, carbohydrate content in the various lignocellulosic biomass increases as the following orders : Magazine < Newsprint < Corrugating container < Computer print out. In the chemical pretreatments for the delignification, sodium hypochlorite pretreatment was more effective than sodium hydroxide. By washing, ash content of lignocellulosic biomass was decreased. Physical pretreatments were less effective than chemical pretreatment for the delignification. On the other hand, in physical pretreatments, ash content of lignocellulosic biomass was the same tendency as in the chemical pretreatments.

• Journal of the Korean Wood Science and Technology
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• v.41 no.2
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• pp.111-122
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• 2013

The steam explosion-chemical pretreatment is a more effective wood pretreatment technique than the conventional physical pretreatment by accelerating reactions during the pretreatment process. In this paper, two-stage pretreatment processes of hardwood were investigated for its enzymatic hydrolysis and the succinic acid yield from the pretreated solid. The first stage pretreatment was performed under conditions of low severity to optimize the amount of solid recovery. In the second stage pretreatment washed solid material from the first stage pretreatment step was impregnated again with chemical (alkaline or chlorine-based chemicals) to remove a portion of the lignin, and to make the cellulose more accessible to enzymatic attack. The effects of pretreatment were assessed by enzymatic hydrolysis and fermentation, after the two stage pretreatments. Maximum succinic acid yield (16.1 g $L^{-1}$ and 77.5%) was obtained when the two stage pretreatments were performed at steam explosion -3% KOH.

• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.330-335
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• 2004

Changes in functional constituents of rice germ prepared using three different heat pretreatments: roasting, steaming and microwave heating, were determined and compared with those of non-treated rice germ. The yield of rice germ oil increased generally and then decreased with increasing time for all three heat pretreatments, although the yields of rice germ oil varied among the three heat pretreatments. There were no major differences in fatty acid compositions among the rice germ oils subjected to the three different heat pretreatments. Levels of $\alpha$-tocopherol in rice germ oil increased up to about 1.5 times at 3 min of roasting and microwave heating, compared to control, and then decreased with increasing treatment time, but $\alpha$­tocopherol concentrations in rice germ oil gradually decreased with increasing steaming time. The contents of three phytosterols ($\beta$-sitosterol, stigmasterol and ergosterol) decreased progressively with increases in roasting and steaming time, while concentrations of the three phytosterols increased up to - 15$\%$ with 3 min of microwave process as compared to control, and then decreased thereafter. Levels of $\gamma$-oryzanol in rice germ oil decreased gradually with increasing time during all three different heat pretreatments. However, levels of $\gamma$ -aminobutyric acid (GABA) in rice germ decreased gradually with increasing roasting time, while those of GABA increased greatly up to about 2 times after 10 min of steaming process, and then decreased slowly thereafter. During microwave heating, the contents of GABA increased at 3 min of treatment time and then decreased. These results suggest that microwave heating may be the most suitable processing method to preserve functional constituents in rice germ.

• Journal of the Korean Wood Science and Technology
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• v.40 no.5
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• pp.343-351
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• 2012

A large diameter roundwood is an important element of Korean traditional buildings, Hanok, and is hard to be dried without surface cracks. Four different pretreatments, such as pre-cracking, oil heating, kerfing-oil heating and PEG impregnation, were investigated for reducing the surface cracks of large-diameter roundwood specimens during heat treatment. The roundwood specimens of pre-cracking, oil heating and kerfing-oil heating showed surface cracks during pretreatment, but that of PEG impregnation did not. It was confirmed that kerfing reduced the total crack width. Among the four pretreatments and control only the PEG impregnation roundwood specimen had no crack on both outer and inner surfaces after heat treatment. The PEG impregnation specimen shrank only 1.6% in the tangential direction while the pre-cracking did 8.0%.

• Corrosion Science and Technology
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• v.13 no.6
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• pp.224-232
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• 2014

Effect of pretreatments on the graphene coated bipolar plate of proton exchange membrane fuel cell(PEMFC) was investigated in simulated environments for PEMFC by using electrochemical measurement techniques. Interfacial contact resistance(ICR) between the graphene coated bipolar plate and the gas diffusion layer(GDL) was measured. The value of ICR decreased with an increase in compaction stress($20N/cm^2{\sim}220N/cm^2$). ICR of graphene coated bipolar plate was higher than that of bare 316L stainless steel. However, Potentiodynamic measurement results showed that the corrosion resistance of graphene coated bipolar plate was higher than that of bare 316L stainless steel. $H_2SO_4$ acid pretreatment was the most effective among various pretreatments. The lowest ICR and the corrosion current density were obtained when using $H_2SO_4$ solution pretreatment.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.421-425
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• 2013

The effect of pretreatment on indium-tin oxide (ITO) electrodes has been rarely studied, although that on metal and carbon electrodes has been enormously done. The electrochemical and surface properties of ITO electrodes are investigated after 6 different pretreatments. The electrochemical behaviors for oxygen reduction, $Ru(NH_3){_6}^{3+}$ reduction, $Fe(CN){_6}^{3-}$ reduction, and p-hydroquinone oxidation are compared, and the surface roughness, hydrophilicity, and surface chemical composition are also compared. Oxygen reduction, $Fe(CN){_6}^{3-}$ reduction, and p-hydroquinone oxidation are highly affected by the type of the pretreatment, whereas $Ru(NH_3){_6}^{3+}$ reduction is almost independent of it. Interestingly, oxygen reduction is significantly suppressed by the treatment in an HCl solution. The changes in surface roughness and composition are not high after each pretreatment, but the change in contact angle is substantial in some pretreatments.

• Journal of Periodontal and Implant Science
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• v.42 no.3
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• pp.95-104
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• 2012

Purpose: The purpose of this study was to determine whether increasing the Ti6Al4V surface oxide negative charge through heat ($600^{\circ}C$) or radiofrequency plasma glow discharge (RFGD) pretreatment, with or without a subsequent coating with fibronectin, stimulated osteoblast gene marker expression in the MC3T3 osteoprogenitor cell line. Methods: Quantitative real-time polymerase chain reaction was used to measure changes over time in the mRNA levels for osteoblast gene markers, including alkaline phosphatase, bone sialoprotein, collagen type I (${\alpha}1$), osteocalcin, osteopontin and parathyroid hormone-related peptide (PTH-rP), and the osteoblast precursor genes Runx2 and osterix. Results: Osteoprogenitors began to differentiate earlier on disks that were pretreated with heat or RFGD. The pretreatments increased gene marker expression in the absence of a fibronectin coating. However, pretreatments increased osteoblast gene expression for fibronectin-coated disks more than uncoated disks, suggesting a surface oxide-mediated specific enhancement of fibronectin's bioactivity. Heat pretreatment had greater effects on the mRNA expression of genes for PTH-rP, alkaline phosphatase and osteocalcin while RFGD pretreatment had greater effects on osteopontin and bone sialoprotein gene expression. Conclusions: The results suggest that heat and RFGD pretreatments of the Ti6Al4V surface oxide stimulated osteoblast differentiation through an enhancement of (a) coated fibronectin's bioactivity and (b) the bioactivities of other serum or matrix proteins. The quantitative differences in the effects of the two pretreatments on osteoblast gene marker expression may have arisen from the unique physico-chemical characteristics of each resultant oxide surface. Therefore, engineering the Ti6Al4V surface oxide to become more negatively charged can be used to accelerate osteoblast differentiation through fibronectin-dependent and independent mechanisms.