Abstract Penicillium nordicum, an ochratoxin A (OTA) producer, widely contaminates the surface of dry-cured fermented sausages. Although the meat industry uses antifungal synthetic compounds during ripening, consumers' preferences currently stand up for natural preservatives. The aim of this study was to evaluate the antifungal effect of spices commonly added to dry-cured fermented sausages during their processing on P. nordicum for establishing their value as an alternative strategy to synthetic compounds. The mould strain was grown on a dry-cured fermented sausage-based medium containing oregano, rosemary or thyme. Moreover, an antifungal commercial preparation containing potassium sorbate and natamycin was tested alone and in combination with the spices. The growth rate, OTA accumulation and relative expression of genes involved in OTA biosynthesis (otapks and otanps) and some stress pathways (Hog1 and Rho1) were evaluated. In the growth assessment, the oregano alone or in combination with the antifungal preparation significantly reduced the growth rate. Different patterns were observed at both sampling times for the OTA production and gene expression analyses, and even differences between treatments at the same incubation period were observed. Regarding OTA accumulation, significant reductions were found when adding oregano or rosemary in the presence and absence of the antifungal compounds. While a stimulation of the expression of most of the tested genes was obtained at the initial stages, a repression was generally found at the end of the incubation. This makes sense since the mycotoxin accumulation was usually higher at the initial stages than at the end of the incubation. Accordingly, such spices would allow satisfying the current consumers’ demand for natural preservatives minimising the hazard associated with the OTA presence in cured meats at the same time.

中文翻译：

---

香料对干腌发酵香肠培养基中赭曲霉毒素a产生及相关基因表达的体外抗真菌作用

摘要 Penicillium nordicum 是赭曲霉毒素 A (OTA) 的生产者，广泛污染干腌发酵香肠的表面。尽管肉类工业在成熟过程中使用抗真菌合成化合物，但目前消费者对天然防腐剂的偏好仍然存在。本研究的目的是评估通常添加到干腌发酵香肠中的香料在对北欧松进行加工过程中的抗真菌作用，以确立其作为合成化合物替代策略的价值。霉菌菌株在含有牛至、迷迭香或百里香的干燥发酵香肠培养基上生长。此外，单独测试了含有山梨酸钾和游霉素的抗真菌商业制剂并与香料组合进行了测试。增长率，评估了参与 OTA 生物合成（otapks 和 otanps）和一些应激途径（Hog1 和 Rho1）的基因的 OTA 积累和相对表达。在生长评估中，牛至单独或与抗真菌制剂组合显着降低了生长速度。在 OTA 生产和基因表达分析的两个采样时间都观察到不同的模式，甚至在同一潜伏期的处理之间也观察到了差异。关于 OTA 积累，在抗真菌化合物存在和不存在的情况下添加牛至或迷迭香时发现显着减少。虽然在初始阶段获得了大多数测试基因表达的刺激，但通常在孵化结束时发现了抑制。这是有道理的，因为霉菌毒素在初始阶段的积累通常比孵化结束时要高。因此，此类香料将允许满足当前消费者对天然防腐剂的需求，同时最大限度地减少与腌制肉类中存在的 OTA 相关的危害。