논문 상세보기
pp.138-146
흑목이 버섯의 자실체로부터 열수추출에 의해 흑갈색 색소를 함유한 조다당(crude polysaccharide)을 분획하였고, 이 조다당 분획의 흑갈색 색소 성분을 탈색 제거하기 위해 활성탄을 이용한 흡착공정을 검토하였다. 흡착 평형은 10분 이내의 빠른 시간에 도달하였으며, 최적의 흡착 조건은 pH 7.0 및 온도 40oC에서 조다당 용액 1 mL당 활성탄 16.7 mg을 첨가하였을 때 얻어졌다. 이 때의 최대 흡착효율은 약 80%이었고, 색소 성분의 제거로 다당은 정제되어 1.25배의 정제율을 나타내었다.
한편, 활성탄에 의한 색소의 등온흡착은 Langmuir 등온식에 따랐으며, 흡착속도는 2nd order model 식으로 나타낼 수 있었다. 또, 흡착은 확산을 통해 조절되는 물리적 흡착공정인 것으로 나타났다. 흑목이 버섯 조다당으로부터의 활성탄에 의한 색소흡착 공정은 그동안 보고된 바 없으며, 경제적이고 간편하여 향후 흑목이 버섯 조다당의 색소 제거와 정제 및 이에 의한 다당 정제공정으로서의 가능성이 있는 것으로 판단하였다.
The crude polysaccharide fraction from fruit body of Auricularia auricula were obtained by using hot water extraction and ethanol precipitation. As the crude polysaccharide fraction contained the brownish dark colored compounds, the adsorption study of pigments from the crude polysaccharide using activated carbon was carried out. The pigment compounds showed an absorption characteristic with λmax of 230 nm and the absorbance at 230 nm was taken as color intensity. Adsorption capacity of pigment depended on increase of the activated carbon to sample loading ratio. The adsorption capacity increased with increase of pH and temperature in the pH range of 3.0-7.0 and temperature range of 25-40oC, but decreased in the temperature range of 40-70oC. The optimum capacity was obtained at addition of 16.7 mg activated carbon per mL sample solution (concentration = 3 mg/mL) at pH of 7.0 and temperature of 40oC. Treatment for 10 min was sufficient to achieve the 80% decolorization and 1.25 fold purification of polysaccharide. Langmuir isotherm and pseudo second-order kinetic model provided the best fitting for adsorption of the brownish dark colored compounds onto powdered active carbon. The activation energies of adsorption from the Langmuir isotherm parameter in the ranges of 25-40oC and 40-70oC was -2.54 and 4.38 kcal/g, respectively. The results of low activation energy also indicated that the adsorption process was a physical adsorption which was controlled by diffnsion.
