山藥冷凍乾燥粉對大鼠28天餵飼之安全性評估

Safety evaluation of feeding yam tuber powder to rats by gavage for 28 days

"本研究主要探討冷凍乾燥山藥粉單次劑量及28天連續餵飼大鼠之安全性。以單次最高限制劑量5,000 mg/kg BW山藥粉，經胃管強迫餵飼大鼠並連續觀察14天，結果顯示，經胃管強迫餵飼高劑量之山藥粉並未造成大鼠急性中毒或死亡。進一步選擇以500, 1,000及2,000 mg/kg BW山藥粉，每日胃管強迫餵飼大鼠連續28天，結果顯示，山藥粉經長期餵飼後並未引起大鼠慢性中毒或死亡。試驗期間檢查眼球底部，在2,000 mg/kg BW高劑量處理組與對照組之大鼠無明顯異常。除在高劑量組之雄鼠體重僅在第4週有增重外，其他各組雄鼠及雌鼠均不受影響。飼料消耗量方面，在處理組雌、雄鼠亦無明顯減少。另外，分析各處理組大鼠之血液相及血清生化檢查，雖然部份檢查項目與對照組比較有差異，但並無臨床病理學上顯著意義。唯實驗中發現，餵飼山藥粉大鼠之血清膽固醇、三酸甘油酯及總蛋白含量，均比對照組上升，推測山藥粉具有促進體內蛋白質生成，並改善營養狀態之效果，其中膽固醇與體內類固醇及其他荷爾蒙合成有關。試驗結束後，所有大鼠經大體解剖觀察，評估體內臟器之肉眼及組織病理變化，各處理組均無明顯毒性病理變化。綜合以上結果，餵飼山藥粉對大鼠不具口服急毒性及28天餵飼毒性，由此推估，山藥粉對大鼠餵飼28天之無毒害作用劑量（NOAEL）大於2,000 mg/kg BW，山藥長期食用對哺乳動物安全性高。"

"The objective of this study is to evaluate the single high dose and the 28-day consecutively feeding toxicity of yam tuber powder in Sprague Dawely (SD) rats. For the acute single dose oral toxicity, SD rats were gavaged by gastric tube with the maximum test threshold dose of 5,000 mg/kg body weight (BW) of yam tuber powder. Results showed that the dose of 5,000 mg/kg BW of yam tuber powder caused no death or toxic effect in rats. It appeared the acute oral LD50 of this compound was greater than 5,000 mg/kg BW in rats. In addition, the yam tuber powder was administrated daily by gavage to each treated group consisting of 10 male and 10 female rats with different doses of 0, 500, 1,000, and 2,000 mg/kg BW for 28 days. Rats were observed daily for clinical sign, and body weight and food consumption measured weekly. Before and the end of experiment, ophthalmology was performed on the control and high dose groups. At termination of treatment, all rats were subjected to hematology, blood biochemistry, organ weighing, urinary analyses, autopsy, and pathological examination. No dose-related toxic effect was found in clinical sign, body and organ weight, food consumption, hematology, urinary analyses, and autopsy after yam tuber powder consecutive supplement for 28 days. However, rats treated with yam tuber powder showed the increase in serum cholesterol, triglyceride and total protein levels in both sexes. This finding suggested that yam tuber powder intake might relate to increase in protein and hormones related synthesis, and improve the nutrition status. Evaluation of clinical observation, mortality, body and organ weight, food consumption, ophthalmology, hematology, biochemistry and pathology data revealed no significant change related to the yam tuber powder consecutive supplement for 28 days. According to the result, the no observed adverse effect level (NOAEL) of yam tuber powder in the 28-day feeding toxicity (by gavage) is greater 2,000 mg/kg BW in rats, as well as the long-term supplement of yam tuber powder is safe in mammalian."