a School of Marine Science and Technology , Harbin Institute of Technology , Weihai , Shandong , China.
b Key Laboratory of Marine Biogenetic Resources , Third Institute of Oceanography, State Oceanic Administration , Xiamen , China.
Bioengineered. 2019 Dec;10(1):13-22. doi: 10.1080/21655979.2019.1586055.
The deep-sea bacterium strain FA13 was isolated from the sediment of the South Atlantic Ocean and identified as Bacillus circulans based on 16S ribosomal DNA sequence. Through liquid fermentation with five media, the cell-free supernatant fermented with ISP2 showed the highest inhibition activities against mycelial growth of Aspergillus parasiticus mutant strain NFRI-95 and accumulation of norsolorinic acid, a precursor for aflatoxin production. Based on ISP2, uniform design was used to optimize medium formula and fermentation conditions. After optimization, the inhibition efficacy of the 20-time diluted supernatant against A. parasiticus NFRI-95 mycelial growth and aflatoxin production was increased from 0-23.1% to 100%. Moreover, compared to the original protocol, medium cost and fermentation temperature were significantly reduced, and dependence on seawater was completely relieved, thus preventing the fermentor from corrosion. This is the first report of a deep-sea microorganism which can inhibit A. parasiticus NFRI-95 mycelial growth and aflatoxin production.
从南大西洋海底沉积物中分离到一株深海细菌 FA13，根据 16S 核糖体 DNA 序列鉴定为环状芽孢杆菌。通过五种培养基的液体发酵，ISP2 发酵的无细胞上清液对产黄青霉突变株 NFRI-95 的菌丝生长和黄曲霉素前体桔青霉素的积累表现出最高的抑制活性。基于 ISP2，采用均匀设计对培养基配方和发酵条件进行了优化。优化后，20 倍稀释上清液对 A. parasiticus NFRI-95 菌丝生长和黄曲霉毒素产生的抑制率从 0-23.1%提高到 100%。此外，与原始方案相比，培养基成本和发酵温度显著降低，完全摆脱了对海水的依赖，从而防止了发酵罐的腐蚀。这是首次报道一种能抑制产黄青霉 NFRI-95 菌丝生长和黄曲霉毒素产生的深海微生物。
