호기성 미생물의 배양중 산소전달 및 소비를 계량적으로 표현하는 방법을 고찰하였다. 용존산소가 미생물에 이르기까지의 과정을 5단계로 모델화하였으며 이들 단계중 특히 film resistance에 대해 고찰하였다. 일단 균체에 전달된 산소는 균체의 표면에 형성된 film resistance를 통해 균에 이른다. 균이 pellet을 형성하였을 때 균사체내에서의 diffusion rate와 diffusion되면서 일어나는 산소의 소비속도와의 관계를 Lumped model 및 Distributed model을 도입하여 설명하였고, 계량화 하였다.

In this research, characteristics of nitrification and denitrification using the microorganism attached on sponge and plates were examined. The denitrification and nitrification performance were investigated under the anaerobic and aerobic condition for about 2 months. Because the basins of denitrification and nitrification were connected in series, wastewater was flowed from denitrification basin to nitrification one. The 90% of influent flowrate was returned from nitrification basin to denitrification one. Most of organic material was removed in nitrification basin, wherease the only exact amount of organics required in denitrification process was removed in denitrification one. This experiment resulted in that heterotrophic bacteria existing in aerobic basin governed the removal efficiency of organic compounds. In case the influent BOD concentration into nitrification basin was 80mg/l, it did not affect to accumulation of nitrifying bacteria, the balance of heterotrophic bacteria was proved to be an important factor in nitrification/denitrification method such as anaerobic and aerobic cycling type.

Recent studies on enzyme reactions in organic solvents are revived. The reactions are classified into three categories: heterogeneous, biphasic and homogeneous systems. The following subjects are described and discussed about the heterogeneous system. 1) The maximal expression of enzyme activity in organic solvents in terms of water content, hydration of enzyme, and equilibriun of water between enzyme and substrate solution. 2) Solvent effect on the catalytic power of enzyme. 3) Thermostability and thermoreactivity. 4) Applications of the enzyme reactions to synthetic chemistry.

1978년 2월에 소곡주의 시험양조를 행하고 발효과정중의 성분변화와 미생물의 변화를 조사하였다. 밑술의 발효에서 3일만에 젖산균의 최우세미생물이 되고 술덧의 pH는 4.2로 낮아졌다. 그러나 7일에 가서는 최우세미생물이 젖산균에서 효모로 바뀌고, pH는 3.6이 되었으며, 술덧의 당화효소 활성도는 초기의 10에서 3.6으로 줄어들었다. 덧술의 발효과정중 pH와 산도는 큰 변화없이 pH 3.5∼3.7 및 산도 8.0∼8.8을 유지하였다. 20일까지는 에탄올 발효가 왕성하게 진행되었으나 40일 이후에서는 에탄올 18.5%에서 발효가 정지상태를 맞이하면서 발효하지 못한 환원당을 술덧에 남기기 시작했다. 술덧의 당화효소 활성도는 발효말기까지 지속되긴 했지만 너무 미약한 것으로 생각되었다. 60일간 발효기켜 여과한 소곡주 최종제품은 에탄올 18.8%, 환원당 5.0%, 총산 0.44%, 휘발산 0.057%, 아미노산 0.206% 및 extract 7.3%를 함유하였다. 관능 검사에서 소곡주는 시판되는 법주나 청주와 비슷한 수준의 좋은 평가를 받았다. 색은 담황색이고, 누룩의 맛과 냄새가 부드럽게 느껴지며, 신맛이 약간 강하였다.

A microorganism, isolated from soil and designated Pseudomonas sp13, produced two kinds of rhamnolipid in the medium containing glucose as carbon source. There were both rhamnolipid contain L-rhamnose and β-hydroxydecanoic acid. Coumpound A and B elucted chloroform-methanol mixed solution of silicic acid column chromatography and recrystallized from a mixture of ether and n-hexane. Studies on the structure of these products reveled that compound A is L-rhamnopyranosyl-β-hydroxydecanoyl-β-hydroxydecanoic acid and compound B is L-rhamnopyranosyl-L-rhamnopyranosyl-β-hydroxydecanoyl-β-hydroxydecanoic acid.

Lipases catalyzed the transesterification reaction between esters and various primary and secondary alcohols in a 99% organic medium, porcine pancreatic, yeast, mold lipases can vigorously act as catalysts in a number of nearly anhydrous organic solvents. Various transesterification reactions catalyzed by porcine pancreatic lipase in hexane obey Michaelis-Menten kinetics. The dependence of the catalytic activity of the enzyme in organic media on the pH of the aqueous solution from which it was recovered is bell-shaped, with the maximum coinciding with the pH optimum of the enzymatic activity in water. The catalytic power exhibited by the lipases in organic solvents is comparable to that displayed in water. In addition to transesterification, lipases Can catalyze several other processes in organic media.