探討Chitinibacter tainanensis醱酵條件及其對植物病原菌之拮抗效果

Study on "Chitinibacter Tainanensis" Fermentation Conditions and its Antagonistic Effect against Plant Pathogens

陳志義(Chih-I Chen) ； 黃功銘(Gong-Ming Huang)

《修平學報》 26期 (2013/03) Pp. 65-78

摘要

本研究使用Chitinibacter tainanensis菌種進行發酵，生產幾丁質酵素與N-乙醯葡萄糖胺酶，並評估對植物病原菌的拮抗作用。結果發現，當使用yeast extract 為氮源時，添加碳酸鈣當做緩衝鹽類，菌量將達到2.54克/ L。同時，利用幾丁質為碳源，產出幾丁質酵素 13.2mU/mL、N-乙醯葡萄糖胺酶558.3mU/mL，分別在醱酵液之上清液可穫得。由實驗結果知，醱酵液沉澱仍然保留幾丁質酵素和N-乙醯葡萄糖胺酶的活性。因此，使用的50 mM Tris-HCl 緩衝液（pH7.4），從沉澱細胞洗滌出殘餘酶的活性。結果顯示，在超音波震盪10 分鐘後，幾丁質酵素7.17 mU/ml 與N-乙醯葡萄糖胺酶558.3mU/ml。收集醱酵液及緩衝洗滌液，進行測試對植物病原菌的拮抗作用影響；在各種微生物測試結果發現醱酵上清液對水稻秧苗立枯病有明顯之抑菌能力，但含酶緩衝洗滌液沒有拮抗作用。這結果證明，醱酵上清液的拮抗作用，是來自一些未知的化學品，非屬幾丁質酵素和N-乙醯葡萄糖胺酶。它需進一步的研究，顯示了真正的化合物與發酵液的拮抗作用機制。

關鍵字

幾丁質酵素 ； N-乙醯葡萄糖胺酶 ； 水稻秧苗立枯病 ； 拮抗作用 ； 病原菌

並列摘要

In this study, the fermentation of Chitinibacter tainanensis was carried out to produce chitinase and N-acetyl-glucosaminidase and to evaluate their antagonistic effects against plant pathogens. It was found that when using yeast extract as the nitrogen sources and calcium carbonate as the buffer salt, the cell mass would reach 2.54 g/L. Meanwhile, by using chitin as the carbon source, the chitinase and N-acetyl-glucosaminidase would reach 13.2 mU/mL and 558.3 mU/mL respectively in the supernatant of the harvested broth.It was observed that the cell precipitate of the broth still reserved chitinase and N-acetyl-glucosaminidase activities. Accordingly, 50 mM Tris buffer( pH7.4) was used to wash out the residual enzymes activities from the cells. The result showed that 7.17 mU/ml of chitinase and 558.3 mU/ml of N-acetyl-glucosaminidase can be obtained under a 10-min sonication. To test the effect of these collected solutions to the antagonistic effects against plant pathogens, various microorganisms were used in the tests. It was found that the supernatant displayed a significant inhibitive effect on Scherotium rolfsii. Whereas, the washing-out buffer containing enzymes showed no antagonistic effect. This result proved that the antagonistic effect of the broth was due to some unknown chemicals and not from chitinase and N-acetyl-glucosaminidase. Further investigations should be performed to reveal the real compounds and mechanism about this antagonistic effect of the fermentation broth.

並列關鍵字

chitinase ； N-acetyl-glucosaminidase ； Chitinibacter tainanensis ； antagonism ； Sclerotium rolfsii

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