Malterud K E, Diep O H, Sund R B
Department of Pharmacognosy, University of Oslo, Norway.
Pharmacol Toxicol. 1996 Feb;78(2):111-6. doi: 10.1111/j.1600-0773.1996.tb00190.x.
A number of isomeric or chemically closely related C-methylated dihydrochalcones, which is a rare substance class, has been isolated from the fruit exudate of Myrica gale L. and subjected to the following tests: 1) inhibition of lipid peroxidation induced by tert-butyl hydroperoxide or bromotrichloromethane in isolated rat hepatocytes, 2) inhibition of peroxidation induced by Fe2+ ions in a cell free system with linolenic acid as substrate, 3) scavenging activity against the diphenylpicrylhydrazyl radical, and 4) inhibition of enzymatic lipid peroxidation in linoleic acid by soybean 15-lipoxy-genase. One of the compounds (myrigalone B = MyB; 2',6'-dihydroxy-4'-methoxy-3',5'-dimethyldihydrochalcone) showed good activity in all tests whereas the others were inactive or slightly active, except that myrigalone A (MyA; 3-(1-oxo-3-phenylpropyl)-1,1,5-trimethylcyclohexane-2,4,6-trione)) like its synthetic analogue MyA* (the polar part of MyA) was nearly as active as MyB in 4). The antioxidant properties of MyB are probably due to its radical scavenging activity and may be related to its conformation, which differs from that of the other compounds.
从杨梅（Myrica gale L.）的果实渗出物中分离出了多种同分异构体或化学结构相近的C-甲基化二氢查耳酮，这是一类稀有物质，并对其进行了以下测试：1）在分离的大鼠肝细胞中抑制叔丁基过氧化氢或溴三氯甲烷诱导的脂质过氧化；2）在以亚麻酸为底物的无细胞体系中抑制Fe2+离子诱导的过氧化；3）对二苯基苦味酰基自由基的清除活性；4）抑制大豆15-脂氧合酶对亚油酸的酶促脂质过氧化。其中一种化合物（杨梅酮B = MyB；2',6'-二羟基-4'-甲氧基-3',5'-二甲基二氢查耳酮）在所有测试中均表现出良好的活性，而其他化合物则无活性或活性较弱，不过杨梅酮A（MyA；3-(1-氧代-3-苯基丙基)-1,1,5-三甲基环己烷-2,4,6-三酮）与其合成类似物MyA*（MyA的极性部分）在4）中几乎与MyB活性相当。MyB的抗氧化特性可能归因于其自由基清除活性，并且可能与其构象有关，其构象与其他化合物不同。
