• 동아시아식생활학회지
• /
• 제12권6호
• /
• pp.547-553
• /
• 2002

This study was attempted to enhance the contents of dietary fiber and minerals of cooked rice by adding four different levels of carrot juice in cooking water (0%:A. 10%:B. 20%:C. 30%:D). The degree of gelatinization and retrogradation, sensory evaluation. and in vitro digestion ratio were tested. These results concluded that the rice cooked with 10～20 % of carrot juice in cooking water was quite acceptable. the optimum cooking conditions fur the rice were one hour presoaking time, 160% cooking water to rice ratio. 20 minutes heating time and 10 minutes steamed cooking.

• Bulletin of the Korean Chemical Society
• /
• 제20권11호
• /
• pp.1299-1302
• /
• 1999

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used to demonstrate cross-linking of peptides induced by transglutaminase. The presence of ε-( Υ-glutamyl)lysine isopeptide cross-link in the acid hydrolysate of the cross-linking reaction mixture was also demonstrated by MALDI-TOF-MS without prior separation. MALDI-TOF-MS quickly provided peptide mass maps after pronase digestion of the cross-linked peptide adduct, which enabled us to monitor the hydrolytic sequence. Pronase appears to preferentially hydrolyze peptide bonds distant from the cross-link before hydrolyzing peptide bonds around the cross-link. The results suggest that pronase digestion followed by MALDI-TOF-MS could be used for determination of amino acid sequence around a modification site.

• Journal of Biosystems Engineering
• /
• 제37권4호
• /
• pp.233-244
• /
• 2012

Purpose: The kinetic evaluation was performed for swine manure (SM) degradation and biogas generation. Methods: The SM was anaerobically digested using batch digesters at feed to inoculum ratio (F/I) of 1.0 under mesophilic conditions ($36.5^{\circ}C$). The specific gas yield was expressed in terms of gram total chemical oxygen demand (mL/g TCOD added) and gram volatile solids added (mL/g VS added) and their effectiveness was discussed. The biogas and methane production were predicted using first order kinetic model and the modified Gompertz model. The critical hydraulic retention time for biomass washout was determined using Chen and Hashimoto model. Results: The biogas and methane yield from SM was 346 and 274 mL/ TCOD added, respectively after 100 days of digestion. The average methane content in the biogas produced from SM was 79% and $H_2S$ concentration was in the range of 3000-4108 ppm. It took around 32-47 days for 80-90% of biogas recovery and the TCOD removal from SM was calculated to be 85%. When the specific biogas and methane yield from SM (with very high TVFA concentration) was expressed in terms of oven dried volatile solids (VS) basis, the gas yield was found to be over estimated. The difference in the measured and predicted gas yield was in the range of 1.2-1.5% when using first order kinetic model and 0.1% when using modified Gompertz model. The effective time for biogas production ($T_{Ef}$) from SM was calculated to be in the range of 30-45 days and the critical hydraulic retention time ($HRT_{Critical}$) for biomass wash out was found to be 9.5 days. Conclusions: The modified Gompertz model could be better in predicting biogas and methane production from SM. The HRT greater than 10 days is recommended for continuous digesters using SM as feedstock.

• 상하수도학회지
• /
• 제29권2호
• /
• pp.183-192
• /
• 2015

Response surface methodology (RSM) based on a Box-Behnken Design (BBD) was applied to optimize the thermal-alkaline pre-treatment operating conditions for anaerobic digestion of flotation scum in food waste leachate. Three independent variables such as thermal temperature, NaOH concentration and reaction time were evaluated. The maximum methane production of 369.2 mL $CH_4/g$ VS was estimated under the optimum conditions at $62.0^{\circ}C$, 10.1% NaOH and 35.4 min reaction time. A confirmation test of the predicted optimum conditions verified the validity of the BBD with RSM. The analysis of variance indicated that methane production was more sensitive to both NaOH concentration and thermal temperature than reaction time. Thermal-alkaline pretreatment enhanced the improvement of 40% in methane production compared to the control experiment due to the effective hydrolysis and/or solubilization of organic matters. The fractions with molecular weight cut-off of scum in food waste leachate were conducted before and after pre-treatment to estimate the behaviors of organic matters. The experiment results found that thermal-alkaline pre-treatment could reduce the organic matters more than 10kD with increase the organic matters less than 1kD.

• 유기물자원화
• /
• 제21권3호
• /
• pp.43-52
• /
• 2013

본 연구에서는 유입 슬러지에 다양한 전처리 방법을 적용하여 전처리 방법이 중온혐기-고온호기 복합 슬러지 처리 공정의 슬러지 소화효율과 메탄가스 생성량에 미치는 영향을 비교 검증하였다. 실험실 규모의 슬러지 소화장치를 제작하여 서로 다른 유입 슬러지 전처리방법을 적용하여 4단계로 실험을 진행하였다. 1단계에서는 전처리를 하지 않은 슬러지를 공급하였고, 2, 3, 4단계에서는 각각 열처리, 열-알칼리처리, 장기 알칼리 처리(7일)를 거친 유입 슬러지를 공급하였다. 실험 결과, 1단계에서 4단계까지 진행되는 동안 총COD 제거율은 44%에서 76%까지 증가하였으며, 메탄 생성량 또한 101mL/L/day에서 165, 256mL/L/day까지 크게 증가하였다. 한편, 4단계에서는 7일간의 장기 알칼리 처리를 하였음에도 불구하고 3단계에 비해 총COD 제거율과 메탄 생성량이 증가하지 않았다. 결론적으로, 유입 슬러지의 전처리를 통해 복합 슬러지 처리 공정의 슬러지 제거 효율과 메탄생성량을 크게 증가시킬 수 있었으며, 여러 가지 전처리 방법 중 열-알칼리 처리법이 가장 효율적임을 실험결과를 통해 알 수 있었다.

• 분석과학
• /
• 제16권5호
• /
• pp.399-406
• /
• 2003

본 연구는 수소화물 발생장치가 부착된 원자흡광 광도계 (HG-AAS)를 이용하여 비교적 고농도의 Se을 함유하고 있는 석유정제 폐수의 Se 분석을 위하여 적합한 분석조건을 선정하고자 수행되었다. Se(VI)의 Se(IV)로의 환원 실험에서 폐수량 10 mL, 염산 주입량 10 mL, 가열시간 30분이 최적 환원조건으로 결정되었다. 폐수의 조성성분과 유기물의 농도가 높은 경우에는 Se 회수율이 감소하였다. 따라서 3가지 산분해법 ($HNO_3/HClO_4$ 분해, $KMnO_4$ 분해 및 초단파 산분해)에 의한 유기물, 석유화합물 분해 및 유기성 Se(org.), Se(IV) 산화에 따른 Se 회수율을 검토하였다. 실험결과 산분해전 약 50~80%이었던 Se 회수율은 모든 산분해에서 90%이상이었으며 특히, 초단파 산분해에 의한 Se 회수율이 가장 높은 것으로 나타났다. 그러므로 HG-AAS를 이용한 석유정제 폐수의 Se 분석시에는 초단파 산분해후 염산 처리를 하는 전처리 과정이 가장 적합한 것으로 나타났다.

• 한국농공학회논문집
• /
• 제62권2호
• /
• pp.17-29
• /
• 2020

The objective of this study was to find an optimum methane yield condition in anaerobic digestion of sewage sludge with microwave pretreatment. The pretreatment process was carried out using a lab scale industrial microwave unit (2,450 MHz frequency). The digestion efficiency of pretreated sludge was evaluated by biochemical methane potential (BMP) test. Box-Behnken design and Response Surface Analysis (RSA) were applied to determine the optimal combination of sludge mixing ratio (0 to 100%), power (400 to 1600 W), holding time (0 to 10 min) and pretreatment temperature (60 to 100℃). BMP test results showed that Volatile Solid (VS) removal efficiency was up to 48% at a condition of 0% for mixing ratio, 1600 W for power, 5 min for holding time, and 80℃ for pretreatment temperature. Methane production was up to 832.3 mL/g VS_removed at a condition of 50% for mixing ratio, 1000 W for power, 5 min for holding time, and 80℃ for pretreatment temperature. The results of the variance analysis (ANOVA) showed that the p-value of the power and pretreatment temperature among the independent variables were significant (p<0.05), and in particular, the pretreatment temperature significantly affected on the solubilization and methane production. The optimum condition for the maximum methane yield (847 mL/g VS_removed) was consist of 38.4% of mixing ratio, 909.1 W of power, 4.1 min of holding time, and 80℃ of temperature within the design boundaries.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권8호
• /
• pp.1127-1133
• /
• 2006

This study examined the effect of cane molasses and fermentation time on chemical composition and characteristics of oat grass silage (OGS) and its in situ digestion kinetics, intake, digestibility, milk yield and composition in buffaloes (Bubalus bubalis). Oat grass (OG) harvested at 50-days of age was ensiled in laboratory silos with cane molasses at the rate of 0, 2, 4 and 6% of OG dry matter (DM) for 30, 35 and 40 days. Silage pH was decreased while lactic acid content increased with increasing level of cane molasses and fermentation time. Dry matter (DM), crude protein (CP) and true protein (TP) content of OGS were (p<0.05) significantly higher with higher cane molasses levels. However, they were not affected by the fermentation time. Similar trends were observed for neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose, acid detergent lignin and ash content of OGS. The OG ensiled for 30-days with 2% molasses was screened from laboratory study and used to determine comparative in situ DM and NDF digestion kinetics of OG and its silage. In situ DM and NDF digestibilities of OG were significantly (p<0.05) higher than OGS. Ruminal DM and NDF lag time, rate and extent of digestion of OG and its silage were similar. Two experimental diets of OG and OGS were formulated using 75:25 forage to concentrate ratio on a DM basis. Dry matter and CP intakes were similar in lactating buffaloes fed either OG- or OGS-based diets. However, NDF intake was higher in buffaloes fed the OG-compared with OGS-based diet. Apparent DM, CP and NDF digestibilities were similar in lactating buffaloes fed either OG- or OGS-based diets. Milk yield (4% FCM) was similar in buffaloes fed either OG-(10.3 kg/d) or OGS-(9.95 kg/d) based diets. Milk fat, total solids and true protein content were higher with OG compared with the OGS diet. Solids not fat and CP content were similar in milk of buffalo fed either OG or OGS. The results of this study indicate that OG ensiled with 2% molasses could safely replace 75% DM of green oat fodder in the diets of lactating buffaloes without negatively affecting intake, digestibility, milk yield and composition.

• 유기물자원화
• /
• 제26권2호
• /
• pp.85-93
• /
• 2018

톱밥 깔짚우사에서 채취한 젖소 분으로부터 바이오가스를 생산하는 효율을 분석하기 위하여 반 건식혐기소화 실험을 수행하였다. 첫 번째 실험으로서 젖소 분과 돈분 슬러리 그리고 두 가지 축분을 일정비율로 혼합한 재료를 대상으로 메탄 발생 잠재량(BMP; Biochemical Methane Potential) 실험을 수행하였다. 혐기소화 실험기간 동안 발생된 메탄가스의 누적량은 젖소 분이 포함된 처리구에서 더 많은 것으로 나타났다. 두 번째 실험으로서 깔짚우사에서 채취한 젖소 분을 단독으로 소화조에 투입하여 반 건식 혐기소화 실험을 실시하였다. 실험 결과, TS (Total Solids) 농도가 13%인 젖소 분의 적정 HRT (Hydraulic Retention Time)는 25일인 것으로 분석되었으며, TS 농도가 13%인 반응조에서의 바이오가스 발생량은 1.36~1.50v/v-d의 범위였고 평균은 1.44v/v-d 수준이었다. 젖소 분의 TS 농도를 15% 수준으로 설정한 혐기소화조에서의 적정 HRT는 30일이었으며 반응조에서의 바이오가스 발생량은 1.50~1.61v/v-d 수준이었고 평균은 1.47v/v-d 수준이었다. TS 농도가 17% 수준인 혐기소화조에서의 최적 HRT는 30일인 것으로 분석되었다. 이 반응조에서의 바이오가스 발생량은 1.50~1.61v/v-d 이었고 평균은 1.55v/v-d 수준이었다.

• 분석과학
• /
• 제24권6호
• /
• pp.510-518
• /
• 2011

최근 질량분석기와 다차원 크로마토그래피 분석법과 대용량 데이터를 처리하는 생물정보학 프로그램 등과 같은 복합적인 기술요소들의 발전은 대량 프로테옴을 분석하는 것을 가능하게 했다. 하지만, 이런 대량의 프로테옴을 분석하는 것은 단백질 절편화 과정의 긴 소요 시간과 낮은 재현성으로 인하여 한계를 가진다. 이 연구에서는 어쿠스틱 기술을 이용해 빠르게 단백질을 분해하는 새로운 방법을 제시했다. 이 어쿠스틱 기술의 시간과 강도를 최적화하기 위해서 여러 가지 조건에서 BSA 단백질을 트립신으로 절편화한 후 액체 크로마토그래피와 질량분석기로 분석하였다. 16시간동안 인큐베이션하는 기존의 방법과 슈퍼 어쿠스틱 기술을 사용한 방법을 비교하였을 때 슈퍼 어쿠스틱 기술이 기존의 방법보다 더 높은 아미노산 동정율을 보였으며, 유방암 세포와 같은 단백질 복합체에 적용하였을 때 30분의 절편화 시간에서도 효율적인 결과를 확인할 수 있었다. 이 새로운 방법은 샘플 전처리 과정에서 많은 양의 단백질일지라도 더 좋은 효율성을 가지게 되고 또한, 소비되는 시간도 줄여주며 일정 시간내의 샘플 처리량도 증가하게 된다.