Polygonum odoratum essential oil inhibits the activity of mushroom derived tyrosinase
Polygonum odoratum essential oil inhibits the activity of mushroom derived tyrosinase
复制标题
DOI：
10.1016/j.heliyon.2019.e02817
复制
发表时间：
2019-11-01
期刊：
影响因子：
4
通讯作者：
Kubo, Isao
中科院分区：
文献类型：
--
作者：
Murray, Anne Frances;Satooka, Hiroki;Kubo, Isao
植物衍生化合物因其在食品保鲜等领域的广泛应用而成为长期研究的热点。植物化学物质在这一领域至关重要的一个关键方式是扰乱酶的功能。采用水蒸气蒸馏法从玉竹(俗称越南香菜)的鲜叶中提取挥发油，并对香菇酪氨酸酶(EC1.14.18.1)催化的L-3，4-二羟基苯丙氨酸(L-DOPA)氧化具有明显的抑制作用。通过GC-MS分析，从挥发油中鉴定出25个化合物。挥发油中含量最丰富的化合物是烷醛-十二醛(55.49%)和正十二醛(11.57%)-其次是大茴香醛(6.35%)，通过单一化合物筛选分别考察了这些化合物的抑制活性。UV-Vis光谱和耗氧实验表明，前三个最丰富的化合物均能抑制酪氨酸酶催化的L-多巴的氧化。当与酪氨酸酶预先孵育时，主要化合物的抑制活性增强，并且没有显著的额外耗氧量，表明K(CAT)类型的失活不参与。主要烷烃的头部和尾部成分的相互作用可能会破坏酶的三级结构，呈现潜在的抑制机制。
Plant derived compounds are a source of long term research focus due to their applications in a variety of fields, particularly food preservation. One key way in which phytochemicals are crucial in this area is by disrupting enzyme functionality. In this work, essential oil was extracted by steam distillation from the fresh leaves of Polygonum odoratum (Polygonaceae), commonly known as Vietnamese coriander, and shown to effectively inhibit the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) catalyzed by mushroom tyrosinase (EC1.14.18.1). Using GC-MS analysis, twenty five compounds were identified in the essential oil. The most abundant compounds in the essential oil were Alkanals - dodecanal (55.49%), and decanal (11.57%) - followed by anisaldehyde (6.35%); these compounds were individually investigated for inhibitory activity by performing single-compound screening. Each of the top three most abundant compounds inhibited the tyrosinase-catalyzed oxidation of L-DOPA, as identified by UV-VIS spectroscopy and oxygen consumption assays. The inhibitory activity of the major compounds increased when pre-incubated with tyrosinase and without significant additional oxygen consumption, suggesting k(cat)-type inactivation is not involved. Interactions of the head and tail components of the major alkanals may disrupt the tertiary structure of the enzyme, presenting a potential inhibitory mechanism.