다시마 Laminaria iaponicus 알긴산의 분자량 분포에 미치는 가수분해 온도의 영향

Abstract

To prepare oligouronic acids from high-molecular-weight alginates prepared from sea tangle (Laminaria japonica), the alginates were hydrolyzed at various temperatures for 1 hr at pH 5.0. The effects of hydrolysis temperature <TEX>$(H_{Temp})$</TEX> on the average molecular weight (AMW) and distribution ratio of MW (DR) in the hydrolyzed alginates were investigated. As <TEX>$(H_{Temp})$</TEX> increased, the AMW of the alginates decreased exponentially; in addition the DR of the alginates with MW>500 kDa decreased exponentially, while the DR of those with MW=50-100 and MW<50 kDa increased exponentially. For the alginates with MW=300-500 and MW=100-300 kDa the DR increased exponentially until <TEX>$H_{Temp}$</TEX> reached <TEX>$80^{\circ}C$</TEX>, and then decreased exponentially at above <TEX>$80^{\circ}C$</TEX>. AS <TEX>$H_{Temp}$</TEX> increased, the MW cutoff size and AMW Of the alginates fraction With the highest DR both decreased. For <TEX>$H_{Temp}<60^{\circ}C$</TEX>, the MW cutoff size with the highest DR was MW>500 kDa; the DR was 39-67% and the AMW 1,000-1,300 kDa. For <TEX>$H_{Temp}$</TEX> <TEX>$80^{\circ}C$</TEX>, the MW cutoff size with the highest DR was MW=300-500 kDa and the DR was about 33% and the AMW about 400 kDa. For <TEX>$H_{Temp}\;100-121^{\circ}C$</TEX>, the MW cutoff size with the highest DRs was MW=50-100 kDa, with a DR of 39-44% and an AMW of 70-80 kDa.