In vitro Study on the Functionality in Digestive Tract of Chitin and Chitosan from Crab Shell

게껍질 Chitin 및 Chitosan의 소화관내 기능성에 관한 in vitro 연구

Chitin and chitosan samples prepared from crab's shells under different conditions were compared for their physicochemical properties; and functionality in gastrointestinal tract by in vitro test. Their bulk density was in the range of $127{\sim}208\;mg/ml$, and their viscosity was $80{\sim}581\;cP$ in 0.1 chitin and $80{\sim}3,670\;cP$ in 0.5% chitosan solution, showing a wide variation. The degree of deacetylation in chitosan samples as determined by IR spectral analysis was relatively high, showing $81{\sim}93%$. At the same alkali concentration and reaction temperature, a longer reaction period gave an increased degree of deacetylation and lower viscosity. The water holding capacity of chitic substance became greater at higher soaking temperature; chitosan D at $37^{\circ}C$ showed the greatest value. Chitic substance with lower bulk density showed the higher water holding capacity. The retardation effect toward glucose absorption was higher in critic substances of lower density and higher water holding capacity; chitosan D showed the highest value of 38%. The retardation index toward bile acid absorption after 1 hour dialysis was $15{\sim}34%$ in chitic substances, 39% in pectin and 9% in cellulose. The retarding effect showed the highest value of 34% in chitosan D at 3% concentration.

반응 조건을 달리하여 게껍질에서 chitin을 추출하고 이를 탈아세틸화하여 chitosan을 제조하였으며, 이들의 물리, 화학적 특성과 소화관내 기능성을 in vitro법으로 실시하였다. 이들 chitin질의 bulk density는 $127{\sim}208\;mg/ml$, 점도는 0.1% chitin의 경우 $80{\sim}581\;cP$, 0.5%, chitosan은 $80{\sim}3,670\;cP$로 다양한 수치를 나타냈으며, chitosan의 탈아세틸화도는 $81{\sim}93%$로 비교적 높았다. Chitosan 제조시의 알칼리 농도와 반응 온도가 일정할 때 반응 시간이 경과할수록 탈아세틸화도는 증가하였고, 점도는 감소하는 경향을 보였다. Chitin질의 보수력은 온도 상승에 따라 약간 상승하였고, $37^{\circ}C$에서 chitosan D가 가장 높았으며, bulk density가 낮을수록 높은 보수력을 나타냈다. Glucose 흡수 억제 효과는 bulk density가 낮고 보수력이 큰 chitin길이 더 컸고 chitosan D가 가장 높은 38%를 나타냈다. Chitin질의 bile acid 흡수 억제 효과는 투석 1시간 후에 $15{\sim}34%$를 나타냈고, pectin은 39%, cellulose는 9%를 나타냈으며 chitosan D는 3% 농도에서 34%의 가장 높은 억제 효과를 나타냈다.