담수조류 그물말로부터 당 용액의 효율적 제조를 위한 가수분해 방법 = Hydrolysis Methods for the Efficient Manufacture of Sugar Solutions from the Freshwater Alga Water-net (Hydrodictyon reticulatum)

다국어 초록 (Multilingual Abstract)

To explore hydrolysis methods for the efficient manufacture of sugar solutions from the freshwater alga Water-net (Hydrodictyon reticulatum, HR), acid hydrolysis, enzymatic hydrolysis, and combined hydrolysis (acid followed by enzymatic hydrolysis) were investigated. In the one-step acid hydrolysis, the reaction of 8% solids content using 2% sulfuric acid at 120oC for 1 hour was desirable. In this case, glucose 27.44 g 100 g DM-1 could be obtained from the HR-d13 samples. In the two-step acid hydrolysis, the primary hydrolysis (HR powder : 72% sulfuric acid = 1 g : 1.5 mL) was carried out for 1 hour at 60oC, and then the secondary hydrolysis was done for 1 hour at 120oC after addition of distilled water 23.5 mL. In this case, glucose 35.11 g/100 g DM could be obtained from the HR-d13 samples. In the combined hydrolysis, 25% solids content using 2% hydrochloric acid were reacted for 1 hour at 120oC, and then citrate buffer and hydrolysis enzyme complexes (E1 1.0 mL+E2 0.2 mL g-1 dried matter) were added and reacted for 1 – 2 days at 50oC. In this case, glucose 33.5 g 100 g DM-1could be obtained from the HR-d23+26 samples. In conclusion, combined hydrolysis was likely to be more useful saccharification method of HR biomass at a practical level, considering the glucose productivity, generation of fermentation-inhibiting substances(hydroxyl methyl furfural, furfural), and limited use of strong acid.

국문 초록 (Abstract)

담수조류인 그물말 (Hydrodictyon reticulatum, HR)의 실용적 당화조건 확립을 위해 산 가수분해 방법으로서 onestepacid hydrolysis과 two-step acid hydrolysis, 그리고 산가수분해 후 효소가수분해를 병행하는 combined hydrolysis를 검토하였다. One-step acid hydrolysis의 경우, 120oC에서 HR 4% 고형분을 2% 황산 용액에 넣어 1시간 동안 반응시킬 경우가 적정하였다. Two-step acid hydrolysis의 적정조건은 1차 가수분해시 HR 건조중: 72% 황산을 1 g : 1.5mL로 하여 60oC에서 1시간 반응시킨 다음, 증류수 23.5 mL를첨가하고 120oC에서 1시간 가수분해시키는 것이었다.
Combined hydrolysis의 경우, 2% 염산에 25%의 HR 고형분을 넣고 120oC에서 1시간 반응시킨 후, citrate buffer로4% 고형분 함량이 되도록 희석하고 E1+E2 효소를 각각1+0.2 mL g DM-1 수준으로 첨가하여 50oC에서 1~2일 동안 반응시키는 것이 바람직하였다. Glucose 생성량, 발효억제물질(HMF, furfural) 생성량, 강산 사용제한 등을 종합적으로 감안할 때, combined hydolysis가 보다 유용할 것으로 판단되었다.

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