Abstract
This work was designed as basic studies on the development of diet for the treatment of obesity. The effect of alginic acid which is the major component of brown algae was investigated by comparing with agar, cellulose, carboxymethylcellulose (CMC), chitin, and lignin as dietary fibers. These dietary fibers ($10\%$) supplemented to basic diet were fed ad libitum to Sprague Dawley rat for 4 weeks, and the inhibitory effects on obesity were evaluated by measuring body weight gain and feed efficiency, the content of glucose and cholesterol in serum, lipase activity in serum, lipid content in liver, adipose tissue around epididymis and ovarium, and Lee index etc. Among the inhibitory effect of these dietary fibers on obesity, lignin was the most effective (p<0.001), followed by Na-alginate (p<0.01) for body weight gain, but lignin was the most effective, followed by CMC, and followed by Na-alginate for feed efficiency (p<0.001). In the inhibitory effects on lipid accumulation in liver and adipose tissue around epididymis and ovarium, lignin and Na-alginate group among these dietary fibers were more effective than others, but there was no significant difference between male and female. The inhibitory effect on obesity evaluated by Lee index was effective in the order of Na-alginate>lignin>CMC>chitin>cellulose (p<0.001). The decreasing effects of lipid content in liver by dietary fibers were found in the order of agar>CMC>cellulose>Na-alginate>chitin>lignin (p<0.001). Glucose content in serum was significantly decreased in cases of CMC, lignin and Na-alginate, whereas a slight difference was found in chitin, but cholesterol content in serum was decreased for all dietary fibers examined except cellulose group. The increasing effect of lipase activity in plasma was found in cases of Na-alginate and chitin, while cellulose, CMC and lignin groups were decreased.
비만치료식 개발을 위한 기초연구로서, 해조류, 특히 미역, 다시마 등 갈조류에 $20{\sim}30\%$ 함유하고 있는 알긴산의 비만에 미치는 영향을 이미 연구되어있는 agar, cellulose, CMC, chitin, lignin 등의 식물섬유의 비만억제작용과 비교하기 위하여 margarine으로 비만을 유도시킨 흰쥐를 사용, 이들 식물섬유들의 비만억제작용에 미치는 영향을 비교, 검토하여 몇 가지 유의성있는 결과를 얻었다. 이들 식물섬유첨가($10\%$)의 비만억제효과를 체중증가량으로 보면 lignin이 가장 효과적이었고 (P<0.001). 그다음이 Na-alginate 였으며(P<0.01), 사료효율로 보면 lignin이 가장 효과적이었고, 그 다음이 CMC, Na-alginate의 순이었다(P<0.001). 간장과 부역환 및 난소 주위의 지방조직에 있어서 지방축적억제효과는 lignin이 가장 효과적이었고, 그 다음이 Na-alginate, cellulose, CMC의 순이었다(P<0.001). 또 Lee index에 의한 비만억제효과를 비교하여 보면 Na-alginate>lignin>CMC>chitin>cellulose의 순이었으며(P<0.001), 간장의 지질함양 분석에 의한 지방축적억제효과를 비교하여 보면 agar>CMC>cellulose>Na-alginate>chitin>lignin의 순으로 효과적임을 알 수 있었다(P<0.001). 식물섬유 첨가에 의한 혈청 glucose 감소효과는CMC가 가장 효과적이었고, 그 다음이 Na-alginate, lignin의 순이었으며(P<0.001), 혈청 cholesterol 저하작용은 Na-alginate가 가장 효과적이었고 그 다음이 lignin, cellulose의 순이었으며 그밖에 chitin을 제외한 대부분이 효과가 있었다. 또한 lipase 활성의 상승작용을 보면 Na-alginate가 가장 효과적이었고 그 다음이 chitin이었다. 따라서 lignin은 목질소로서 나무의 목질부의 주성분이기 때문에 실제 식품으로서 섭취가 쉽지 않기 때문에 미역, 다시마 등 갈조류의 $20-30\%$ 함유하고 있는 알긴산이 비만의 예방과 치료에 가장 효과적인 것으로 생각된다.