• Title/Summary/Keyword: PRETREATMENT

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The Influence of Temperature Pretreatment on the Production of Microspore Embryos in Anther Culture of Capsicum annuum L. (고추 (Capsicum annuum L.)의 약배양 시 온도 전처리가 소포자배 발생에 미치는 영향)

  • 김문자
    • Korean Journal of Plant Tissue Culture
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    • v.26 no.2
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    • pp.71-76
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    • 1999
  • Anthers of two hot pepper cultivars, Milyang-jare and Geryongsan-jare, were cultured on MS medium containing 0.1 mg/L 2,4-D and 0.1 mg/L kinetin. The influence of pretreatment at 4$^{\circ}C$ and 32$^{\circ}C$ on induction of microspore embryo was investigated. Milyang-jare was superior to the Geryongsan-jare in microspore embryo induction. The 32$^{\circ}C$ pretreatment increased embryo induction compared to the 4$^{\circ}C$ pretreatment while the 4$^{\circ}C$ pretreatment stimulated callus induction. Microspore embryos were regenerated to plantlets in the same medium or hormone free medium at 32$^{\circ}C$ treatment but most embryos failed to develop directly into plantlets at 4$^{\circ}C$ treatment. The optimal period of the 32$^{\circ}C$ pretreatment was 3 days in Milyang-jare and 6 days in Geryongsan-jare. The 32$^{\circ}C$ pretreatment was essential for induction and growth of microspore embryo in pepper.

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Pretreatment of Wasted Corn Stalk from Gangwon Province for Bioethanol Production (강원지역 폐옥수수대로부터 바이오에탄올 생산을 위한 전처리 방법 개발)

  • Choi, Jae Min;Kang, Se Young;Yeom, Sung Ho
    • Journal of the Korea Organic Resources Recycling Association
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    • v.19 no.3
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    • pp.79-89
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    • 2011
  • The wasted corn stalk from Gangwon province is composed of 44.6 % glucan, 19.0 % xylan, 23.8 % lignin, 4.5 % ash and 8.1 % others. Statistical analysis, full factorial design, revealed that temperature was the most influential factor in the dilute sulfuric acid pretreatment and that the influence of temperature on xylose yield was 3.5 and 3.2 times higher than those of treatment time and acid concentration, respectively. Temperature was also the most influential factor for glucose yield in the pretreatment but it was less than 5 % throughout the pretreatment. Although minor sugar yield was observed when microwave or ultrasonication was solely introduced as a pretreatment method, the complex method incorporating microwave or ultrasonication into dilute sulfuric acid pretreatment enhanced sugar yield significantly. In particular, xylose yield was doubled when microwave and dilute sulfuric acid treatment was sequentially applied. The optimization of pretreatment and enzymatic hydrolysis as well as the investigation on the complex pretreatment in detail are left for further study.

Byproducts formation during hydrothermal pretreatment of spent mushroom substrate and effects onto biogas production efficiency (버섯 폐배지의 수열전처리 과정 중 중간산물 생성이 바이오가스 수율에 미치는 영향)

  • Jongkeun Lee;Daegi Kim
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.1
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    • pp.27-34
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    • 2023
  • In this study, spent mushroom substrate (SMS), which consits of lignocellulosic material, was pretreated by hydrothermal method; the changes of biodegradability and methane production yield of pretreated SMS were determined according to formation of lignocellulosic biomass degrading byproducts formation during thermal pretreatment. Based on the results, all hydrothermal pretreatment temperatures showed improved solubilization performance for biomass, and the optimum pretreatment effect was observed at an pretreatment temperature of 150℃ with the highest methane production yield. However, the induced formation of furan derivatives (i.e., 5-hydroxymethylfurfural and furfural) as byproducts during hydrolysis of hemicellulose and cellulose at severe condition lowered biodegradability and methane yield when the hydrothermal pretreatment temperature was higher than 180℃. Thus, this study revealed that hydrothermal pretreatment could promote anaerobic digestion efficiency of lignocellulosic biomass and is of great importance for preventing byproducts formation through pretreatment condition control.

Effects of Thermal Pretreatment Temperature on the Solubilization Characteristics of Dairy Manure for Dry Anaerobic Digestion

  • Ahn, Heekwon;Lee, Seunghun;Kim, Eunjong;Lee, Jaehee;Sung, Yongjoo
    • Korean Journal of Soil Science and Fertilizer
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    • v.47 no.2
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    • pp.127-132
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    • 2014
  • The effect of thermal pretreatment conditions on hydrolysis characteristics of dairy manure and sawdust mixtures has been evaluated. Thermal pretreatment temperature varied between 35 and $120^{\circ}C$ and the period of the treatment changed between 30 and 1440min (24h). As thermal pretreatment temperature and duration increased, organic material solublization rates were improved. Maximum solubilizations of chemical oxygen demand (SCOD), carbohydrates, and volatile fatty acids(VFAs) were observed when dairy manure treated for one day at $120^{\circ}C$. Although one day treatment duration at $120^{\circ}C$ showed the highest SCOD, soluble carbohydrates, and VFAs concentration, its hydrolysis rate was only about 12%. The results reveal that the thermal pretreatment conditions tried in this study are not enough to solubilize the organic matter contained in dairy manure and sawdust mixtures. In order to maximize hydrolysis performance, the further research needs to determine the factors influences on organic material solubilization in addition to thermal pretreatment temperature and duration.

Effect of Naringin Pretreatment on Bioavailability of Verapamil in Rabbits

  • Yeum, Cheul-Ho;Choi, Jun-Shik
    • Archives of Pharmacal Research
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    • v.29 no.1
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    • pp.102-107
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    • 2006
  • The aim of present study is to investigate the effect of naringin on the pharmacokinetics of verapamil and its major metabolite, norverapamil in rabbits. The pharmacokinetic parameters of verapamil and norverapamil were determined after administering verapamil (9 mg/kg) orally to rabbits in the pretreated with naringin (1.5, 7.5, and 15 mg/kg). Naringin pretreatment significantly altered the pharmacokinetic parameters of verapamil. Compared with the control group (given verapamil alone), the $K_a,\;C_{max}$ and AUC of verapamil were significantly (p<0.05 or p<0.01) increased in the pretreatment of naringin, However there were no significant change in $T_{max}\;and\;t_{1/2}$ of verapamil. Consequently, pretreatment of naringin significantly (p<0.05, p<0.01) increased the AB% of verapamil significantly in a dose dependent manner (p<0.05 or p<0.01 ), and elevated the RB% of verapamil by 1.26- to 1.69-fold. the MR of verapamil were significantly (p<0.05) increased in the pretreatment of naringin, implying that pretreatment of naringin may effectively inhibit the CYP3A4-mediated metabolism of verapamil. In conclusion, pretreatment of naringin enhanced the oral bioavailability of verapamil. Based on these results, the verapamil dosage should be adjusted when given with naringin or a naringin-containing dietary supplement.

Effect of Different Pretreatment Methods on the Bioconversion of Rice Bran into Ethanol

  • Eyini, M.;Rajapandy, V.;Parani, K.;Lee, Min-Woong
    • Mycobiology
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    • v.32 no.4
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    • pp.170-172
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    • 2004
  • The efficiency of acid, enzyme and microbial pretreatment of rice bran was compared based on the content of cellulose, hemicellulose, reducing sugars and xylose in the substrate. An isolate of Aspergillus niger or a strain of Trichoderma viride(MTCC 800) was employed for microbial pretreatment of rice bran in solid state. Acid pretreatment resulted in the highest amount of reducing sugars followed by enzyme and microbial pretreatment. A. niger showed a higher rate of hydrolysis than T. viride. The rice bran hydrolysate obtained from the different methods was subsequently fermented to ethanol either by Zymomonas mobilis(NCIM 806) or by Pichia stipitis(NCIM 3497). P. stipitis fermentation resulted in higher ethanol(37% higher) and biomass production($76{\sim}83%$ higher) than those of Z. mobilis. Maximum ethanol production resulted at 12h in Zymomonas fermentation, while in Pichia fermentation, it was observed at 60h. Microbial pretreatment of rice bran by A. niger followed by fermentation employing P. stipitis was more efficient but slower than the other microbial pretreatment and fermentation.

Effect of Ethanol Pretreatment on the Toluene Metabolism in Toluene-treated Rats (흰쥐에 있어서 주정중독이 Toluene 대사에 미치는 영향)

  • 윤종국;윤선동;신중규
    • Toxicological Research
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    • v.12 no.2
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    • pp.243-250
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    • 1996
  • To evaluate an effect of ethanol pretreatment on the toluene metabolism, toluene (50% in olive oil) was given three times at 0.2 ml/100g body weight at the interval of one day to the rats fed with 5% ethanol during two months. The ethanol pretreated rats were not identified particular liver injury by the histopathologic findings. In case of toluene treatment, the ethanol pretreatment to the rats led to more increased concentration of urinary hippuric acid than those treated with only toluene. The ethanol pretreatment to the rats led to the increased activities of hepatic aniline hydroxylase and these enzyme activities were higher both in toluene treated and those pretreated with ethanol, but no differences were found in two groups. Ethanol pretreated rats showed the more increased activities of benzylalcohol dehydrogenase than control group. Moreover, the ethanol pretreatment to the toluene treated rats led to significantly more increased activities of benzylalcohol dehydrogenase compared with those treated with toluene only. Furthermore, the alcohol pretreatment to the toluene treated rats also led to somewhat higher activities of benzaldehyde dehydrogenase than those treated with toluene. In conclusion, these results indicate that the chronic pretreatment of ethanol at not so much liver damage as normal may rather activate the toluene metabolism.

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Influences of Testosterone and Estrogen on the Contractile Sensitivity to Oxytocics, the Cholinesterase activity and Electrolytes of the Uterine Muscle of Rabbits (Testosterone 및 Estrogen 투여(投與)가 자궁수축약(子宮收縮藥)의 적출자궁(摘出子宮) 수축성(收縮性)에 미치는 영향(影響)과 자궁근내(子宮筋內) Cholinesterase 활성도(活性度) 및 전해질(電解質)에 미치는 효과(?果))

  • Koo, Hee-Soo;Kong, Wha-Soon;Kim, Soon-Yeung;Song, Hyun-Sub;Lee, Jeung-Ja
    • The Korean Journal of Pharmacology
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    • v.6 no.1
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    • pp.45-55
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    • 1970
  • It is well known that the uterine contractility is affected by sexual hormone. In this experiment, the authors attempted to study the influences of testosterone and estrogen or the uterine contractility to oxytocics. The contractile sensitivity of the excised uterine muscle of non-castrated and castrated rabbits with testosterone and estrogen 24 hours before experiment is observed respectively. And the cholinesterase activity and electrolytes (Na, K, Ca and Mg) in the uterine muscle are measured in order to study the relationship with contractile sensitivity and those changes. The results obtained were summarized as follows: 1. The contractile effect of spareng on the excised uterine muscle of non-castrated rabbits pretreated with estrogen was markedly increased in small dose, but that of rabbits pretreated with testosterone was significantly increased in large dose, comparing with that of the control group. In castrated rabbits, the contractile sensitivity of the uterine muscle to spareng was significantly increased by pretreatment with estrogen in large dose but it was markedly decreased by pretreatment with testosterone in small dose. 2. The contractile effect of quinine on the excised uterine muscle of non-castrated rabbits pretreated with estrogen was significantly decreased but that of castrated rabbits pretreated with both estrogen and testosterone were markedly increased comparing with that of the control group. 3. The cholinesterase activity in the uterine muscle of non-castrated rabbits was significantly increased by pretreatment with small dose of estrogen or large dose of testosterone, but that of castrated rabbits was markedly decreased by pretreatment with large dose of estrogen. 4. Na and K contents in the uterine muscle of non-castrated rabbits were markedly increased by pretreatment with both estrogen and testosterone, but that of castrated rabbits was significantly increased by pretreatment with small dose of estrogen. 5. Ca content in uterine muscle of non-castrated rabbits was significantly decreased by pretreatment with both large dose of estrogen and testosterone but increased by pretreatment of testosterone. In castrated rabbits, Ca content was significantly decreased by pretreatment with both estrogen and testosterone. 6. Mg content in the uterine muscle of non-castrated rabbits was markedly increased by pretreatment with estrogen and small dose of testosterone, but that of castrated rabbits was significantly decreased by pretreatment with both large dose of estrogen and testosterone.

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Optimization of Microwave-Assisted Pretreatment Conditions for Enzyme-free Hydrolysis of Lipid Extracted Microalgae (탈지미세조류의 무효소 당화를 위한 마이크로파 전처리 조건 최적화)

  • Jung, Hyun jin;Min, Bora;Kim, Seung Ki;Jo, Jae min;Kim, Jin Woo
    • Korean Chemical Engineering Research
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    • v.56 no.2
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    • pp.229-239
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    • 2018
  • The purpose of this study was to effectively produce the biosugar from cell wall of lipid extracted microalgae (LEA) by using microwave-assisted pretreatment without enzymatic hydrolysis process. Response surface methodology (RSM) was applied to optimization of microwave-assisted pretreatment conditions for the production of biosugar based on enzyme-free process from LEA. Microwave power (198~702 W), extraction time (39~241 sec), and sulfuric acid (0~1.0 mol) were used as independent variables for central composite design (CCD) in order to predict optimum pretreatment conditions. It was noted that the pretreatment variables that affect the production of glucose (C6) and xylose (C5) significantly have been identified as the microwave power and extraction time. Additionally, the increase in microwave power and time had led to an increase in biosugar production. The superimposed contour plot for maximizing dependent variables showed the maximum C6 (hexose) and C5 (pentose) yields of 92.7 and 74.5% were estimated by the predicted model under pretreatment condition of 700 w, 185.7 sec, and 0.48 mol, and the yields of C6 and C5 were confirmed as 94.2 and 71.8% by experimental validation, respectively. This study showed that microwave-assisted pretreatment under low temperature below $100^{\circ}C$ with short pretreatment time was verified to be an effective enzyme free pretreatment process for the production of biosugar from LEA compared to conventional pretreatment methods.

Effects of Pretreatment on the Field Germination Rate of Some Tree Seed (종자(種子)의 전처리(前處理)가 몇 수종(樹種)의 포장발아율(圃場發芽率)에 미치는 영향(影響))

  • Kim, Gab-Tae
    • Journal of Korean Society of Forest Science
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    • v.78 no.1
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    • pp.26-29
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    • 1989
  • To seek for a proper pretreatment method for increasing field germination rate, field germination rate of 5 tree species including Phellodendron amurense was investigated and was compared among pretreatment methods. The results obtained in this study were as follows ; 1. Field germination rates of Poncirus trifoliata and Fraxinus rhynchophylla among pretreatment methods were significantly different at 1% level, and that of Phellodendron amurense among pretreatment methods were significantly different at 5% level. In thses species, highest field germination rate was observed on the plot of cold moist stratification under the ground (Nochunmaejang ; during 166 days). 2. Field germination rates of Chaenomeles sinensis among pretreatment methods were significantly different at 1% level, and highest field germination rate was observed on the plot of cold moist stratification in the refrigerator (during 110days). 3. Field germination rates of Cudrania tricuspidata among pretreatment methods were not significantly different at 5% level.

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