Abstract：
Fungi outbreaks in water will include a series of processes, including spore aggregation, germination, biofilm, and finally present in a mixed state in the aquatic environment. More attention is paid to the control of dispersed fungal spores, however, there was little knowledge of the control of germinated spores. This study investigated the inactivation kinetics and mechanism of ultraviolet (UV) treatment for fungal spores with different germination percentages compared with dormant spores. The results indicated that the inactivation rate constants (k) of spores with 5%-45% germination were 0.0278-0.0299 cm2/mJ for Aspergillus niger and 0.0588-0.0647 cm2/mJ for Penicillium polonicum, which were lower than those of dormant spores. It suggested that germinated spores were more tolerant to UV irradiation than dormant spores, and it may be due to the defensive barrier (upregulated pigments) and some reductive substance (upregulated enoyl reductase) by absorbing UV or reacting with reactive oxygen species according to transcriptome analysis. Compared to dormant spores, the k-UV of germinated spores decreased by 18.17%-26.56% for Aspergillus niger, which was less than k-chlorine (62.33%-69.74%). A slighter decrease in k-UV showed UV irradiation can efficiently control fungi contamination, especially when dormant spores and germinated spores coexisted in actual water systems. This study indicates that more attention should be paid to germinated spores.
摘要：
水中的真菌爆发将包括一系列过程，包括孢子聚集，发芽,生物膜，最后在水生环境中以混合状态存在。更多的关注分散真菌孢子的控制，然而,对发芽孢子的控制知之甚少。本研究研究了与休眠孢子相比，紫外线（UV）处理对具有不同发芽率的真菌孢子的失活动力学和机理。结果表明，黑曲霉萌发率为5％-45％的孢子的失活速率常数（k）为0.0278-0.0299cm2/mJ，波兰青霉为0.0588-0.0647cm2/mJ。低于休眠孢子。这表明发芽的孢子比休眠的孢子更耐受紫外线照射，这可能是由于防御屏障（上调色素）和一些还原性物质（上调烯酰还原酶）通过吸收紫外线或根据转录组分析与活性氧反应。与休眠孢子相比，黑曲霉萌发孢子的k-UV降低了18.17%-26.56%,低于k-氯(62.33%-69.74%)。k-UV的轻微下降表明UV照射可以有效地控制真菌污染，特别是当休眠孢子和发芽孢子共存于实际水系统中时。这项研究表明，应更加重视发芽的孢子。
