Modified Mutation Method for Screening Low Citrinin-ProducingStrains of Monascus purpureus on Rice Culture

微生物四微生物四鄭宇倫鄭宇倫

9213401992134019

secondary metabolitessecondary metabolites

Monascus Monascus speciesspecies 的二級代謝產物的二級代謝產物 (i) pigments(i) pigments (ii) antihypercholesterolemic agents(ii) antihypercholesterolemic agents

monacolin Kmonacolin K hypotensive agent, hypotensive agent, γγ-aminobutyric acid (GABA)-aminobutyric acid (GABA)

(iii) antioxidant compounds(iii) antioxidant compounds dimerumic aciddimerumic acid 3-hydoxy-4-methoxy-benzoic acid3-hydoxy-4-methoxy-benzoic acid

(iv) antibacterial activity compound(iv) antibacterial activity compound pigmentpigment citrinin (monascidin)citrinin (monascidin)

CitrininCitrinin Monascus Monascus speciesspecies 首先於首先於 19311931 從從 Penicillium citrinumPenicillium citrinum 發現；隨後在發現；隨後在 AspeAspe

rgillum rgillum spp.spp. 與與 Monascus Monascus spp.spp. 發現發現 mycotoxinmycotoxin LDLD5050=67 mg/kg=67 mg/kg 影響影響

Antimicrobial inhibitory effectsAntimicrobial inhibitory effects Phytotoxic inhibitory effectsPhytotoxic inhibitory effects Cytotoxic inhibitory effectsCytotoxic inhibitory effects Hypocholesterolemic inhibitory effectsHypocholesterolemic inhibitory effects Enzyme inhibitory effectsEnzyme inhibitory effects

目的目的

建立簡單快速篩選方式，篩選低建立簡單快速篩選方式，篩選低 citrinincitrinin 產產生的突變株生的突變株

原理原理

CitrininCitrinin 具有抑制具有抑制 Bacillus subtilisBacillus subtilis 生長，在生長，在MonascusMonascus strain strain 的菌落周圍形成 的菌落周圍形成 inhibition inhibition

zonezone

步驟步驟 -- 紅麴菌的培養紅麴菌的培養500g 長粒米浸潤 8h

過篩去水

放入 koji-dish 中，滅菌釜 20min

接種孢子

30 °C 培養 10 天

壓碎榨乾

spores suspension

步驟步驟 -- 突變與篩選突變與篩選

spores suspension

UV Irradiation (death rate 90%) Spread PDA plate(B. subtilis)

Clear zone selection

共同培養 3 天

結果結果 綜合綜合 citrinincitrinin 、、 monacolin Kmonacolin K 和和 GABAGABA 的結果的結果

The mutant strain The mutant strain M. purpureusM. purpureus N 301 N 301 0.23 ±0.01 ppm citrinin0.23 ±0.01 ppm citrinin （降低（降低 50%50% ） ） 481.29 ±7.98 ppm monacolin K481.29 ±7.98 ppm monacolin K （（ 91%91% 產率）產率） 5000 ppm GABA content 5000 ppm GABA content （沒有顯著改變）（沒有顯著改變）

The mutant strain The mutant strain M. purpureusM. purpureus N 310 N 310 0.27 ±0.01 ppm citrinin0.27 ±0.01 ppm citrinin （降低（降低 41%41% ）） 526.29 ±5.54 ppm monacolin K526.29 ±5.54 ppm monacolin K （沒有顯著改變）（沒有顯著改變） 5000 ppm GABA content 5000 ppm GABA content （沒有顯著改變）（沒有顯著改變）

The results showed that the method could be used to sThe results showed that the method could be used to select red mold rice with low citrinin production.elect red mold rice with low citrinin production.