Penicillium islandicum之生長與肝毒性黃米毒素之產生   全文下載

The Growth and Production of Hepatotoxic Luteoskyrin by Penicillium islandicum

本研究在探討影響Penicillium islandicum之生長與黃米毒素產生活性之許多種因素，結果黃米毒素與相關色素之產量是在真菌培養之後期為最高。以多種培養基培養時，菌絲生長及黃米毒素之產量在麥芽糖抽出物培養液中最高。在適當受質中黃米毒素之產量在第18天時為最高，另在靜置培養所得菌絲生長及黃米毒素產量較振盪培養為高，菌絲生長之最適pH值介於微酸性至中性之間。碳源中之澱粉，蔗糖，果糖，麥芽糖與葡萄糖均有促進菌絲生長與黃米毒素及相關色素之產生，其中以澱粉促進菌絲生長與果糖促進黃米毒素產生之活性為最強。乳糖雖能促進黃米毒素及相關色素之產生但抑制菌絲之生長。檸檬酸鹽，麩胺酸鹽，丙二酸鹽，琥珀酸鹽，延胡索酸鹽與乙酸鹽等均抑制菌絲生長。黃米毒素及相關色素之產生，以乙酸鹽之抑制作用最強。氮源中麥芽抽出物，酵母抽出物，蛋白?，酪蛋白氨基酸，天冬醯胺與麩胺醯胺等均可促進菌絲之生長，但是黃米毒素及相關色素產生方面，僅麥芽抽出物，天冬醯胺及麩胺醯胺等有促進作用。穀物中真菌生長與黃米毒素產量依序為糙米＞麥片＞小麥＞精白米＞黃皮玉米＞白皮玉米＞米穀。又精白米經不同方法處理時，烹煮者之產毒量高於乾炒，烘焙及油炸者，添加5%之蔗糖時不但增加米食中之含水量，也使其產毒量更高。 The maximal production of luteoskyrin and related pigments by Penicillium islandicum was obtained during the late phase of cultivation. Maximum growth of mycelial was observed in potato dextrose broth and the highest productivity of luteoskyrin in malt extract broth. In an optimal substrate, luteoskyrin production was the highest in the 18th day. Mycelial growth and luteoskyrin production were greater in stationary incubation than when shaken. The optimal pH for the mycelial growth was between weak acidity and neutrality. Mycelial growth and the production of luteoskyrin and related pigments were increased by supplying a carbon source such as starch, sucrose, fructose, maltose or glucose. Starch and fructose maximized mycelial growth and luteoskyrin production respectively. Lactose also enhanced luteoskyrin production but inhibited mycelial growth. The organic salts citrate, glutamate, malonate, succinate, fumarate and acetate inhibited mycelial growth and the production of luteoskyrin and related pigments. The acetate in particular displayed the strongest inhibitory effects in this test. Mycelial growth was enhanced by the following nitrogen sources: malt extract, yeast extract, peptone, casamino acid, asparagine and glutamine. However, the production of luteoskyrin and related pigments were only enhanced by malt extract, asparagine and glutamine. Potency of mycelial growth and luteoskyrin production in crops was found in the order of unpolished rice > oatmeal> wheat> polished rice> yellow corn> white corn> unhulled rice. A comparison of polished rice which had been subjected to various treatments showed boiled rice to be the best substrate for luteoskyrin production, especially in the presence of 5% sucrose."

The maximal production of luteoskyrin and related pigments by Penicillium islandicum was obtained during the late phase of cultivation. Maximum growth of mycelial was observed in potato dextrose broth and the highest productivity of luteoskyrin in malt extract broth. In an optimal substrate, luteoskyrin production was the highest in the 18th day. Mycelial growth and luteoskyrin production were greater in stationary incubation than when shaken. The optimal pH for the mycelial growth was between weak acidity and neutrality. Mycelial growth and the production of luteoskyrin and related pigments were increased by supplying a carbon source such as starch, sucrose, fructose, maltose or glucose. Starch and fructose maximized mycelial growth and luteoskyrin production respectively. Lactose also enhanced luteoskyrin production but inhibited mycelial growth. The organic salts citrate, glutamate, malonate, succinate, fumarate and acetate inhibited mycelial growth and the production of luteoskyrin and related pigments. The acetate in particular displayed the strongest inhibitory effects in this test. Mycelial growth was enhanced by the following nitrogen sources: malt extract, yeast extract, peptone, casamino acid, asparagine and glutamine. However, the production of luteoskyrin and related pigments were only enhanced by malt extract, asparagine and glutamine. Potency of mycelial growth and luteoskyrin production in crops was found in the order of unpolished rice > oatmeal> wheat> polished rice> yellow corn> white corn> unhulled rice. A comparison of polished rice which had been subjected to various treatments showed boiled rice to be the best substrate for luteoskyrin production, especially in the presence of 5% sucrose.