该研究测定了蜡样芽孢杆菌 (Bacillus cereus) XZ30-2对黑曲霉的抑制活性，制备XZ30-2的发酵液并分析其稳定性，进一步研究发酵液冻干粉对小麦感染黑曲霉的防治效果，并开展发酵液的动物安全性评价。结果表明：蜡样芽孢杆菌XZ30-2对黑曲霉有较强的抑制活性，拮抗带宽5.32 mm，发酵液抑菌率为54.31%；XZ30-2发酵液对紫外光、日光、pH为5~9时具有较强的耐受性，当温度升高到70 ℃时发酵液的抑菌活性开始下降；每100 mL发酵液可制备150 mg冻干粉；利用冻干粉对郑麦366进行黑曲霉防治测定，与对照组相比，处理组无明显可见的黑曲霉菌落，显示XZ30-2发酵液具有良好的防霉效果。发酵液对小鼠的安全性评价中，采用5000 mg/kg·bw最大剂量灌胃14 d内发现小鼠体态正常、体重增加正常、未出现行为异常和死亡现象; 解剖并检查对照组和处理组小鼠的脏器，均未发现可见病变，脏器指数和血清学生理指标均差异不显著，初步确定XZ30-2发酵液的动物安全性。研究结果可为蜡样芽孢杆菌XZ30-2发酵液作为食品防霉剂的进一步开发应用提供理论参考。

The inhibitory activity of Bacillus cereus XZ30-2 against Aspergillus niger was evaluated and the stability of its fermentation supernatant was analyzed. The control effect of lyophilized powder prepared from the fermentation supernatant against A. niger was also studied, and its safety was evaluated in mice. B. cereus XZ30-2 strongly inhibited A. niger growth. The antagonistic bandwidth was 5.32 mm and the inhibitory rate of the fermentation supernatant was 54.31%. The XZ30-2 fermentation supernatant was stable under conditions of ultraviolet light irradiation, sunlight, and pH 5~9. Its antifungal activity began to decrease at 70 ℃. A total of 150 mg lyophilized powder could be prepared from 100 mL fermentation supernatant. The biocontrol efficacy of the lyophilized powder was evaluated using Zhengmai 366. In comparison with the control group, there was no obvious formation of A. niger colonies in the treatment group, indicating good antifungal properties of the XZ30-2 fermentation supernatant. The safety evaluation revealed that even after 14 days of XZ30-2 fermentation supernatant administration by gavage (maximum dose: 5000 mg/kg body weight), the mice demonstrated normal behavior and posture, normal weight gain, no signs of behavioral abnormalities, and no death. No pathological changes were noted in the organs harvested from the mice of the control and treatment groups. The organ and serological physiological indices were also comparable. Thus, XZ30-2 fermentation supernatant appeared to be safe. Collectively, these results provide theoretical basis for the further development and application of B. cereus XZ30-2 fermentation supernatant as an antifungal agent in food.

国家自然科学基金资助项目（81973417）；河南工业大学创新基金支持计划专项资助项目（2020ZKCJ23）