The extract of marine green algae Enteromorpha sp. was evaluated in vitro for inhibitory activity against mushroom tyrosinase enzyme. The principle active agents i.e. coumarin; 4-hydroxycoumarin (1) and two sterols; ergosta-5,7,22-trien-3β-ol (2) & ergosterol peroxide (3) were isolated for the first time, from a crude methanol extract of Enteromorpha sp. showing anti-tyrosinase activity. Their structures were elucidated by IR, extensive NMR spectroscopy, LC-ESI-MS, Single crystal X-ray diffraction techniques. Thus, Enteromorpha sp. can be an alternative edible anti-tyrosinase agent.

中文翻译：

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海藻肠小肠菌酪氨酸酶抑制剂的分离与鉴定

海洋绿藻Enteromorpha sp。的提取物。在体外评估了对蘑菇酪氨酸酶的抑制活性。主要的活性剂，即香豆素；4-羟基香豆素（1）和两种固醇; 首次从Enteromorpha sp。的甲醇粗提物中分离出了ergosta-5,7,22-trien-3β-ol（2）和麦角固醇过氧化物（3）。显示抗酪氨酸酶活性。通过红外，宽泛NMR光谱，LC-ESI-MS，单晶X射线衍射技术阐明了它们的结构。因此，Enteromorpha sp.。可以替代食用抗酪氨酸酶。