Department of Animal Development, University of Belgrade-Faculty of Biology, Belgrade, Serbia.
Department of Algology, Mycology, and Lichenology, University of Belgrade-Faculty of Biology, Belgrade, Serbia.
PLoS One. 2019 Jan 3;14(1):e0209999. doi: 10.1371/journal.pone.0209999. eCollection 2019.
Members of the millipede order Julida rely on dominantly quinonic defensive secretions with several minor, non-quinonic components. The free radical-scavenging activities of ethanol, methanol, hexane, and dichloromethane extracts of defensive secretions emitted by Pachyiulus hungaricus (Karsch, 1881) and Megaphyllum unilineatum (C. L. Koch, 1838) were investigated using the ABTS, DPPH, and total reducing power (TRP) tests. The obtained extracts were also tested for inhibition of acetylcholinesterase and tyrosinase activity. Finally, the antifungal potential of both julid extracts was evaluated against seven Fusarium species. Secretions of both species showed activity against free radicals, acetylcholinesterase, tyrosinase, and all of the selected fungal species. The secretions of P. hungaricus exhibited a more potent antioxidative effect than did those of M. unilineatum, while there were no significant differences of antiacetylcholinesterase activity between the tested extracts. Only the hexane extract of M. unilineatum showed an effect on tyrosinase activity stronger than that of P. hungaricus. Fusarium sporotrichioides, F. graminearum, and F. verticillioides were the fungi most resistant to secretions of both julids. The Fusarium species most susceptible to the secretion of P. hungaricus was F. avenaceum, while the concentrations of M. unilienatum extracts needed to inhibit and completely suppress fungal growth were lowest in the case of their action on F. lateritium. Our data support previous findings that julid defensive secretions possess an antimicrobial potential and reveal their antioxidative and antineurodegenrative properties. Bearing in mind the chemical complexity of the tested defensive secretions, we presume that they can also exhibit other biological activities.
千足虫目 Julida 成员主要依赖醌类防御分泌物，还有几种次要的非醌类成分。使用 ABTS、DPPH 和总还原能力（TRP）试验研究了 Pachyiulus hungaricus（Karsch，1881）和 Megaphyllum unilineatum（C. L. Koch，1838）防御分泌物的乙醇、甲醇、己烷和二氯甲烷提取物的自由基清除活性。还测试了获得的提取物对乙酰胆碱酯酶和酪氨酸酶活性的抑制作用。最后，评估了这两种 julid 提取物对七种镰刀菌属真菌的抗真菌潜力。两种物种的分泌物均对自由基、乙酰胆碱酯酶、酪氨酸酶和所有选定的真菌物种表现出活性。与 M. unilineatum 的分泌物相比，P. hungaricus 的分泌物显示出更强的抗氧化作用，而测试提取物之间的抗乙酰胆碱酯酶活性没有显著差异。只有 M. unilineatum 的己烷提取物对酪氨酸酶活性的影响强于 P. hungaricus。Fusarium sporotrichioides、F. graminearum 和 F. verticillioides 是对两种 julid 分泌物最具抗性的真菌。对 P. hungaricus 分泌物最敏感的镰刀菌属真菌是 F. avenaceum，而 M. unilienatum 提取物抑制和完全抑制真菌生长所需的浓度在其对 F. lateritium 的作用下最低。我们的数据支持以前的研究结果，即 julid 防御分泌物具有抗菌潜力，并揭示了它们的抗氧化和神经退行性特性。考虑到测试防御分泌物的化学复杂性，我们推测它们还可以表现出其他生物活性。
