ABSTRACT

Koji mold, which belongs to the Aspergillus section Nigri, is used in the production of shochu. The section Nigri is composed of very morphologically similar members that in some cases produce mycotoxins, which rises concerns as to whether the presence of mycotoxin-producing fungi in shochu producing sites can compromise consumer safety. Thus, we examined the presence of mycotoxin-producing sec. Nigri fungi in six shochu factories (named A–F) in Japan. Airborne fungal levels in the factories were determined, and a traditional koji called “kona-koji” made from the mold naturally present in factory C (Aogashima village) was analyzed. Isolates of sec. Nigri fungi were identified morphologically and confirmed via cytochrome b gene analysis. In factory A (Nago city), airborne fungal levels of sec. Nigri were 4,000 and 100 cfu/m³ in the koji-making and fermentation rooms, respectively. In factories B, C, and D, the levels were 40, >10⁴ cfu/m³, and 100 cfu/m³, respectively. In factory F (Iki city), there were high levels of airborne white-koji mold (a white mutant of Asp. luchuensis). The most dominant fungal species of sec. Nigri was isolated and identified as Asp. luchuensis via genetic analysis. This is likely to have originated from the commercial fermentation culture used. Asp. niger and Asp. luchuensis were isolated from kona-koji. Mycotoxin production (ochratoxin and fumonisin B2) by Asp. luchuensis (eight strains) and Asp. niger (three strains) was virtually inexistent; only one strain of Asp. niger was positive for fumonisin B₂. This study clearly shows that mycotoxin-producing fungi are not dominant in the fungal flora present in the shochu factories examined and therefore, that the liquor can be safely fermented.

Implications:

In this study, we examined the presence of mycotoxin-producing Aspergillus sec. Nigri fungi in six shochu (Japanese distilled beverage) factories. The most dominant fungal species of sec. Nigri was isolated and identified as Aspergillus luchuensis (black-koji mold). The proportion of mycotoxin-producing Aspergillus niger and Aspergillus carbonarius was very small. In addition, the Asp. niger isolated from koji mold did not have the ability to produce ochratoxins or fumonisin B. This study clearly shows that shochu can be safely fermented.

摘要

酒曲霉菌，属于曲霉属部Nigri，在生产烧酒的使用。本节Nigri由很形态相似的成员，在某些情况下产生霉菌毒素，其上升的担忧为霉菌毒素生产菌的烧酒制作网站的存在是否会危及消费者的安全。因此，我们检查了产生真菌毒素秒的存在。日本六个烧酒工厂（名为A–F）的Nigri真菌。确定了工厂中的空气传播真菌水平，并分析了由工厂C（青岛村）中自然存在的霉菌制成的传统koji-“ kona-koji ”。隔离秒。尼格里通过形态学鉴定真菌，并通过细胞色素b基因分析确认。在工厂A（名护市）中，空运真菌水平为sec。在酒曲制作室和发酵室中，Nigri分别为4,000 cfu / m ³和100 cfu / m ³。在工厂B，C和D中，该水平分别为40，> 10 ⁴ cfu / m ³和100 cfu / m ³。F工厂（壹岐市）的空气传播的白曲霉菌（芦笋的白色突变体）水平很高。秒的最主要真菌种类。Nigri被隔离并鉴定为Asp。琉球通过遗传分析。这很可能源自所用的商业发酵培养物。天冬氨酸 尼日尔和Asp。从kona-koji分离出luchuensis。Asp产生的霉菌毒素（och曲霉毒素和伏马毒素B2）。luchuensis（八株）和Asp。尼日尔（三株）实际上不存在；只有一株Asp。尼日尔伏马毒素B ₂呈阳性。这项研究清楚地表明，在检查过的烧酒工厂中存在的真菌菌群中，产真菌毒素的真菌并不占主导地位，因此可以安全地发酵白酒。

含义：

在这项研究中，我们检查了产生霉菌毒素的曲霉菌的存在。在六个烧酒工厂生产的Nigri真菌。秒的最主要真菌种类。Nigri被分离并鉴定为luchuensis（黑曲霉）。霉菌毒素生产的比例黑曲霉及黑炭黑是非常小的。另外，Asp。从曲霉中分离出的尼日尔不具有产生曲霉毒素或伏马毒素B的能力。这项研究清楚地表明，烧酒可以安全地发酵。