케냐프 코어 전처리를 위하여 전자선 조사와 물찜이 결합된 복합 전처리공정에 대해 연구하였다. 각 시료는 50에서 1,000 kGy까지의 선량으로 조사한 후, 오토클레이브를 이용하여 120 ℃에서 5시간 동안 물찜처리를 하였다. 적외선 분광기와 X선 회절 분석기를 사용하여 전처리 되지 않은 시료와 전처리된 시료의 분자 구조와 결정도 변화를 분석하였다. 전처리 되지 않은 시료의 결정화도 지수는 50.6%에서 500 kGy 조사된 시료는 55.0%로 증가함을 알 수 있었다. 그 다음, 전처리된 시료에 비활성도 70 FPU/mL, 40 CBU/mL의 효소를 주입하여 생산된 단당류 총합으로 당화율을 구하였다. 이 때 효소 가수분해 시간은 24, 48, 72시간으로 하였다. 500 kGy로 조사된 시료의 72 시간 가수분해 후 당화율은 83.9%로 가장 높게 나타났고, 전처리된 시료의 당화율은 조사량 증가에 따라 100 kGy에서 50.8%, 200 kGy에서 58.6%, 300 kGy에서 67.9%로 각각 증가하였다.
We have investigated the combined pretreatment of electron beam irradiation (EBI) and water steam as a kenaf core pretreatment process. After each sample was exposed to electron beam dose ranging from 50 to 1,000 kGy, the irradiated sample was treated by water steam using an autoclave for 5-h at 120 ℃. The pretreated samples were characterized using FTIR-ATR and XRD. FTIR spectra and XRD analysis of nonpretreated and pretreated samples confirm that crystallinity changes were observed before and after the pretreatment. The crystallinity index (CrI) was increased from 50.6% for nonpretreated sample 55.0% for 500 kGy exposed sample. And then, we analyzed sugar yield that is the amount of produced mono-saccharides in pretreated sample by enzymatic hydrolysis; an enzyme activity rate was 70 FPU/mL and 40 CBU/mL, and the loading time was 24, 48 and 72-h. The highest sugar yield was 83.9% at 500 kGy after 72-h for enzymatic hydrolysis. The sugar yield of enzymatic hydrolysis for pretreatment samples was increased as doses are subsequently changed to 100, 200 and 300 kGy, allowing to give 50.8%, 58.6% and 67.9%, respectively.
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