食品工业用红曲菌株产桔青霉素能力的研究

为筛选出低产或不产桔青霉素的红曲霉菌株 ,选用 3 5株食品发酵工业用红曲霉 ,研究不同的培养条件对其产桔青霉素能力的影响。结果显示 ,所有菌株在大米培养基上均产桔青霉素 ,3 0个株菌 (85 71% )在液体培养基上产毒 ;两种培养基上的产毒范围分别为 0 2 8～ 2 458 80mg kg和 0 0 9～ 55 65mg kg ,毒素产量均数分别为 2 0 1 60mg kg和 11 99mg kg ,中位数分别为 61 99mg kg和 3 51mg kg ,同一菌株在大米培养基上产桔青霉素能力高于液体培养基。色价测定结果表明 ,菌株在大米培养基上的色素产量也高于液体培养基 (3～ 50 9倍 ,平均 93倍 )。本研究筛选出一株在大米培养基上色素产量最高 (113 4U g)而桔青霉素产量较低、适用于食品发酵工业用的红曲霉菌株。研究结果提示 ,用于生产食品或保健食品的红曲菌种在使用前必须进行安全性评价 ,并在全国范围内定期对生产厂家、菌种保藏单位使用和保藏的菌种进行产桔青霉素能力调查 ,对红曲发酵产品中桔青霉素污染水平进行监测 ,建立我国红曲制品中桔青霉素的限量标准迫在眉睫

Study on the production of citrinin by Monascus strains used in food industry

In order to screen strains with less or nearly no production of citrinin, thirty-five Monascus strains used in food industry were selected to investigate the effect of cultivation condition and the medium composition on citrinin production. The results from the study indicated that all strains produced citrinin on the rice with the levels ranging from 0.28 to 2458.80 mg/kg (201.60 mg/kg for the average and 61.99 mg/kg for the median, respectively), while 30 strains (85.71%) yielded this toxin on the submerged culture with the concentration between 0.09 and 55.65 mg/kg (11.99 mg/kg for the average and 3.51 mg/kg for the median, respectively). Therefore, citrinin production in rice in this study was higher than that in the liquid. In addition, the red pigment production in rice was 3-509 (average 93) times higher than that in the liquid. One strain with the highest color value (1134 U/g) but lower citrinin production in rice was obtained. These results suggested that it is necessary to make the safety evaluation of microorganisms for the production of foods and food ingredients, to investigate the ability of citrinin production by Monascus strains preserved by either the food manufacturer or the national culture collection units and, to survey the citrinin contamination in Monascus products countrywide. It is urgent for China to establish the tolerance limit of citrinin in foods fermented by Monascus species.