• Journal of Forest and Environmental Science
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• 제36권2호
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• pp.69-77
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• 2020

Lignocellulosic biomass has recalcitrant characteristics against chemical and biological conversion due to its structural heterogeneity and complexity. The pretreatment process to overcome these recalcitrant properties is essential, especially for the biochemical conversion of lignocellulosic biomass. In recent years, pretreatment methods using ionic liquids (ILs) and deep eutectic solvents (DESs) as the green solvent has attracted great attention because of their advantages such as easy recovery, chemical stability, temperature stability, nonflammability, low vapor pressure, and wide liquids range. However, there are some limitations such as high viscosity, poor economical feasibility, etc. to be solved for practical use. This paper reviewed the research activities on the pretreatment effect of various ILs including DESs and their co-solvents with organic solvents on the enzymatic saccharification efficiency of lignocellulosic biomass and the nanocellulose preparation from the pretreated products.

• Korean Chemical Engineering Research
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• 제56권4호
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• pp.542-546
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• 2018

본 연구에서는 해양 거대조류 중 홍조류에 속하는 꼬시레기(Gracilaria verrucosa)로부터 malonic acid를 사용하여 열수 전처리 조건(전처리 온도, 촉매 농도, 고액비, 전처리 시간)에 따른 전처리와 효소가수분해를 통한 바이오슈거(환원당) 생산 가능성을 조사하였다. 300 mM malonic acid, 1:20 고액비 조건에서 $130^{\circ}C$에서 60분간 전처리를 수행하여 49.2%의 환원당 수율을 얻었다. 전처리 반응 후 이어진 효소 가수분해를 통하여 64.5%의 수율을 확보하였다.

• 한국환경과학회지
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• 제16권2호
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• pp.211-218
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• 2007

The objectives of this study have been carried out to investigate the solubilization of municipal sewage sludge by single and dual frequency ultrasonic pretreatment, and the methane production characteristics of pretreated sewage sludge by specific methanogenic activity test for sewage sludge reduction. The waste activated sludge was collected from thickened tank of Suyoung sewage treatment plant in Busan city, and its concentration was adjusted to 1.0% total solids. Ultrasonic frequency was varied 15, 20, 15+20 kHz, and acoustic density was used a maximum 176W/L. The dual frequency ultrasonic pretreatment was found to be more effective than single frequency ultrasonic in the solubilization rate and methane production. The $SCOD_{Cr}/TCOD_{Cr}$, rate were 15.2%, 13.9%, 17.0% with single frequency of 15 kH2, 20 kHz, dual frequency of 15+20 kHz, respectively. The application of dual frequency ultrasound for sewage sludge pretreatment can be interest for sewage treatment plants having problems in sludge treatment and disposal.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2002년도 봄 학술발표대회 발표논문집
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• pp.471-474
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• 2002

SA treatment significantly increased thermotolerance In cucumber seedlings. Pretreatment of seeds with $CaCl_2$ solution enhanced the SA- induced thermotolerance. On the contrary, pretreatment with the $Ca^{2+}$ chelator EGTA lowered this SA-induced thermotolerance. In addition, pretreatment with $Ca^{2+}$ channel blocker verapamil also weakened the SA-induced thermotolerance. However, the calmodulin antagonist chlorpromazine(CPZ) had little effect on the SA-induced thermotolerance. Measurement of activity of the antioxidant enzyme APX and the level of lipid peroxidation (in term of MDA) indicated that heat stress induced an oxidative stress in cucumber seedlings. SA treatment induced higher activities of APX and a lower level of lipid peroxidation. $Ca^{2+}$ pretreatment further enhanced the SA-induced increase in APX activity and lowered the heat stress-induced lipid peroxidation, but EGTA pretreatment had a contrary effect. These results suggest that $Ca^{2+}$ and calmodulin may be involved In the acquisition of the SA-induced thermotolerance; antioxidant enzyme system take part in the final generation of the SA-induced thermotolerance.

• 한국환경성돌연변이발암원학회지
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• 제16권2호
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• pp.83-87
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• 1996

This study was performed by the sister chromatid exchanges (SCEs) to investigate the effects of Aphidicolin (APC) or 2, 4-dinitrophenoi (DNP) on cross-adaptive response to ultraviolet radiation (UV) or ethyl methanesulfonate (EMS) in Chinese hamster ovary (CHO) cells. The pretreatment with 1 J/m$^2$ UV decreased the yield of SCEs induced by subsequent treatment with 8 mM EMS in CHO cells. And the treatment with 10 $\mu$g/ml APC or 50 $\mu$M DNP during incubation after pretreatment with 1 J/m$^2$ UV increased the yield of SCEs induced by 8 mM EMS. The pretreatment with 2 mM EMS decreased the yield of SCEs induced by subsequent treatment with 5 J/m$^2$ UV. The treatment with 10 $\mu$g/ml APC during incubation after 2 mM EMS increased the yield of SCEs induced by 5 J/m$^2$ UV. These results suggest that APC and DNP inhibit cross-adaptive response to pretreatment with UV and subsequent treatment with EMS, and also cross-adaptive response to pretreatment with EMS and subsequent treatment with UV is inhibited by APC in CHO cells.

• 대한약리학회지
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• 제18권1호
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• pp.33-41
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• 1982

In this paper, the influences of adrenergic blockades; propranolol and phenoxybenzamine on the changes of hyperglycemic action, hepatic glycogen content, and brain norepinephrine (NE) content induced by clonidine were investigated in the male mice. The results obtained were summarized as follows: 1) Blood glucose level was significantly increased by clonidine $(30{\mu}g/kg)$. The increase of blood glucose level induced by clonidine was not affect by the propranolol (10mg/kg) pretreatment, but significantly inhibited by the phenoxybenzamine (10mg/kg) pretreatment. 2) Hepatic glycogen content was moderately inhibited by clonidine. The decrease of hepatic glycogen content induced by clonidine was not affected by the propranolol and phenoxybenzamine pretreatment. 3) Brain NE content was significantly increased in 30 minutes and 60 minutes after clonidine treatment. The increase of brain NE content induced by clonidine was significantly inhibited by the phenoxybenzamine pretreatment. The increase of train NE content induced in 90 minutes and 120 minutes after clonidine treatment was more markedly increased by the propranolol pretreatment.

• KSBB Journal
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• 제29권3호
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• pp.193-198
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• 2014

Pretreatment of wastepaper using aqueous glycerol under high pressure was studied to enhance the enzymatic hydrolysis. The pretreatment was conducted over a wide range of conditions including temperatures of $150{\sim}170^{\circ}C$, sulfuric acid concentrations of 0.5~1.5%, and reaction times of 30~90 minutes. After the effect of glycerol concentration on the pretreatment performance was investigated, 70% glycerol was selected. As glycerol concentration was increased, higher digestibility was achieved due to higher lignin removal. The optimum condition was found to be around $160^{\circ}C$, 1%, and 60 minutes. At this condition, 60% and 35% of hemicellulose and lignin, respectively, were removed, while only 5% of cellulose was lost. The enzymatic digestibility was 76%, meaning that 73% of the glucan present in the initial substrate was recovered as glucose after enzymatic hydrolysis. Also, it was found that the temperature and acid concentration than the reaction time were more strongly related to the compositional removals and enzymatic digestibility.

• 상하수도학회지
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• 제22권4호
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• pp.449-454
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• 2008

Some pretreatment methods have been proposed to enhance the biodegradability and to shorten the hydrolysis reaction time. By means of efficient pretreatment the suspended solids (SS) can be made of better accessible for the anaerobic bacteria. There are several ways how this can be accomplished, which include biological, mechanical, thermal, and chemical methods. For the sludge solubilization using the cavitation phenomenon, we have tried to develop a pretreatment process consisted of a reactor and pumps. The objectives of this study were to develop a advanced wastewater treatment consisted of IABR and the cavitation with PGA. The most effective removal for organic matter and nutrients were occured when both cavitation pretreatment and ${\gamma}$-PGA were applied at the IABR process. Only small portion of ${\gamma}$-PGA at a rate of 1.38mg/L, was enough to improve sedimentation ability, SS removal efficiencies, and sludge volume reduction. After the sludge solubilization by the cavitation, SCOD increased to 193% and SS decreased to 36%. The removal ratio of BOD was 94.5%, T-N removal ratio was 85.5% and T-P removal ratio was 84.9%. The combination process of the IABR with the cavitation and PGA addition seems to be very effective alternative wastewater treatment process.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3547-3553
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• 2014

Background: The prognostic value of serum alkaline phosphatase (S-ALP) has not been fully validated for nasopharyngeal carcinoma (NPC). Materials and Methods: S-ALP levels were measured in 601 patients newly diagnosed with NPC before radical treatment, and possible associations of these levels with 5-year overall survival (OS) and tumor-free survival (TFS) were explored using univariate and multivariate analyses. Results: Elevated pretreatment S-ALP (>85 U/L) was significantly less frequent among patients classified as T1+2 or stage I+II than among those classified as T3+4 or stage III+IV. Multivariate analysis showed that elevated pretreatment S-ALP (>85 U/L), age, T classification and N stage were independent predictors of poor OS and TFS. Conclusions: Pretreatment S-ALP may be a reliable biomarker to evaluate the long-term prognosis of patients with NPC.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3443-3446
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• 2014

The aim of this study was to determine predictive factors for neutropenia after docetaxel-based systemic chemotherapy in patients with castration-resistant prostate cancer (CRPC). The study included 40 Korean CRPC patients who were treated with several cycles of docetaxel plus prednisolone from May 2005 to May 2012. Patients were evaluated for neutropenia risk factors and for the incidence of neutropenia. In this study, nine out of forty patients (22.5%) developed neutropenia during the first cycle of docetaxel-based systemic chemotherapy. Four experienced grade 2, three grade 3, and one grade 4 neutropenia. Multivariate analysis showed that pretreatment white blood cell (WBC) count (p=0.042), pretreatment neutrophil count (p=0.015), pretreatment serum creatinine level (p=0.027), and pretreatment serum albumin level (p=0.017) were significant predictive factors for neutropenia. In conclusion, pretreatment WBC counts, neutrophil counts, serum creatinine levels, and serum albumin levels proved to be significant independent risk factors for the development of neutropenia induced by docetaxel-based systemic chemotherapy in patients with CRPC.