| Abstract: | 本研究申請案之目的在深入探討基隆山藥,台農二號及民間長紅山藥機能成份存在之部位,以及探討以較低劑量之山藥濃縮成分調節血脂及腸道功能之可能性.本研究將先制定山藥水溶性萃取物之快速製備方法,再評估飼料中加入5%生山藥水溶性萃取物(內含可溶性多醣及diosgenin配糖體等物質)對血脂質(三酸甘油脂、總膽固醇、LDL膽固醇、HDL膽固醇)、糞便特性(溼份、粒數、短鏈脂肪酸)、腸道菌相(利用PCR技術)、結腸末端黏膜細胞型態等營養生理功能.結果發現各組間每日攝食量、增重及飼料效率、消化器官及肝臟重量並無顯著不同,顯示山藥冷水萃取物中已去除山藥全可食部之抗營養成分,且山藥冷水萃取物並無顯著刺激盲腸及大腸重量增加之效果.在脂質方面,台農二號及基隆山藥顯著降低血漿總膽固醇及低密度膽固醇及提高高密度膽固醇;然而民間長紅顯著降低血漿三酸甘油脂.三種山藥水溶性萃取物皆降低肝臟三酸甘油脂三種,山藥在每日糞便量上,食用民間長紅及台農二號山藥冷水萃取物組有效提高濕重、乾重、糞便顆數及保水度.顯示民間長紅及台農二號山藥冷水萃取物可能比基隆山藥冷水萃取物含較多不消化物質.在小腸黏膜酵素方面,maltase, sucrase及leucine aminopeptidase活性不受山藥冷水萃取物影響.
Chinese yam (Dioscorea spp.) has been used traditionally as medicine for treating diarrhea and has shown beneficial effects on bowel function. It is known that Chinese yam contains several ingredients such as mucilage, diosgenin and dopamine, which may exert special physiological and theraputical effects. The aim of this study was to investigate effects of yam diets (containing 5% water-soluble fraction w/w) on lipid metabolism, activities of endogenous digestive enzymes, stool characteristics, intestinal microflora, cecal and fecal short chain fatty acid concentrations and the morphology of the mucosa cells in the distal colon. We found growth and feed efficiency were not hampered by the yams. All varieties of yams investigated in this study effectively lower the plasma cholesterol, LDL-cholesterol, phospholipid levels and enhance the plasma HDL-cholesterol levels. The hepatic triglyceride levels were significantly decreased by yam water extracts as compared to the control diet. The intestinal hydrolase activites were not influenced by either yam extract. Among all yams, D. alata was the better substrates to increase the colonic fermentation and increase the population of Bif. longum. Therefore, water extract of yam maintained the lipid-modulatory effects of raw yam in Balb/c mice without influencing the growth of mice. However, the extent of colonic fermentation caused by water extract of yam were fewer than that caused by the raw yam. |
