Summary: | 碩士 === 國立臺灣海洋大學 === 食品科學系 === 104 === Stress cause death of live fish during transport. The aim of this study was to increase stress tolerance for Cyprinus carpio koi by adding Glycine tomentella root extract (GTE) as a natural anti-stress drops during transport. Biochemical indices : cortisol, glucose, hematological indices : erythrocyte count (RBC)、hematocrit (HCT)、hemoglobin (Hb) were measured and the histological structure of the gill tissue was examined under simulated commercail transportation of koi to determine the optimum anti-stress GTE drop. The effects of loading density of koi during 48 hours simulated transport in 90 g/L, 120 g/L and 150 g/L loading density showed survival rate of 100%, 70% and 7%, respectively. Thus, a loading density of 130 g/L corresponding to a 50% of survival rate was used for the following experiments with or without the addition of different drops of anti-stress adaptogen during transport. The survival rates were 100 % when GTE was added at 125 ppb, 250 ppb or 500 ppb being higher than the clove oil (100 μL/L) group (66.7%). GTE group showed a significant increase in dissolved oxygen, and decreased conductivity and turbidity. In hematological indices, the RBC and Hct values of clove oil group were significantly higher than the GTE 250 ppb and GTE 500 ppb groups. In the biochemical indices, the content of blood glucose in the GTE groups were significantly lower than the control group. The histological structure of the gill tissue of koi showed lub-shape in the clove oil group; while lifting of epithelial cell and proliferation of interlamella cell of gill tissue in GTE 250 ppb and 500 ppb groups were observed. The gill structure of the GTE 125 ppb group appeared healthy. In conclusion, GTE (125 ppb) lowered the transport stress in koi. Total polyphenols and total flavonoids were analyzed as indicators for the quality control of GTE drop. The validity period of the GTE group stored in a stock solution of 530 ppm at room temperature was 23 months. The difference of total polyphenols between refluxing for 4 hours and soaking-stirring extraction at room temperature for 42 hours was 1.56%. Thus, we recommend extraction of Glycine tomentella root at ambient temperature for industrial process.
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