Swine dysentery and necrotic enteritis are a bane to animal husbandry worldwide. Some countries have already banned the use of antibiotics as growth promoters in animal production. Surfactin is a potential alternative to antibiotics and antibacterial agents. However, the antibacterial activity of Bacillus species-derived surfactin on Brachyspira hyodysenteriae and Clostridium perfringens are still poorly understood. In the current study, the antibacterial effects of surfactin produced from Bacillus subtilis and Bacillus licheniformis on B. hyodysenteriae and C. perfringens were evaluated. Results showed that multiple surfactin isoforms were detected in B. subtilis, while only one surfactin isoform was detected in B. licheniformis fermented products. The surfactin produced from B. subtilis exhibited significant antibacterial activity against B. hyodysenteriae compared with surfactin produced from B. licheniformis. B. subtilis-derived surfactin could inhibit bacterial growth and disrupt the morphology of B. hyodysenteriae. Furthermore, the surfactin produced from B. subtilis have the highest activity against C. perfringens growth. In contrast, B. licheniformis fermented product-derived surfactin had a strong bacterial killing activity against C. perfringens compared with surfactin produced from B. subtilis. These results together suggest that Bacillus species-derived surfactin have potential for development as feed additives and use as a possible substitute for antibiotics to prevent B. hyodysenteriae and C. perfringens-associated disease in the animal industry.

中文翻译：

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芽孢杆菌属表面活性素对猪痢疾短螺旋体和产气荚膜梭菌的抗菌活性

猪痢疾和坏死性肠炎是全世界畜牧业的祸根。一些国家已经禁止在动物生产中使用抗生素作为生长促进剂。Surfactin是抗生素和抗菌剂的潜在替代品。但是，尚不了解芽孢杆菌属来源的表面活性素对猪痢疾短螺旋体和产气荚膜梭状芽胞杆菌的抗菌活性。在当前的研究中，评估了枯草芽孢杆菌和地衣芽孢杆菌产生的表面活性素对猪痢疾短螺旋体和产气荚膜梭菌的抗菌作用。结果表明，在大肠杆菌中检测到多种表面活性素同工型。枯草芽孢杆菌，而在地衣芽孢杆菌发酵产物中仅检测到一种表面活性素同工型。从制得的表面活性的枯草芽孢杆菌显示出显著抗菌活性对猪痢疾短螺旋与来自产生表面活性相比地衣芽孢杆菌。枯草芽孢杆菌衍生的表面活性素可以抑制细菌生长并破坏猪痢疾短螺旋体的形态。此外，枯草芽孢杆菌产生的表面活性素对产气荚膜梭菌的生长具有最高的活性。相反，地衣芽孢杆菌发酵产物衍生的表面活性素对产气荚膜梭菌与枯草芽孢杆菌生产的表面活性素相比。这些结果一起表明，芽孢杆菌属物种衍生的表面活性素具有作为饲料添加剂的发展潜力，并可以用作抗生素的预防动物工业中猪痢疾短螺旋体和产气荚膜梭菌相关疾病的替代品。