Sophoraflavanone G (5,7,2',4'-tetrahydroxy-8-lavandulylflavanone) has been referred as a phytochemical with the intensive antibacterial activity. To elucidate the pharmacological mechanism underlying an antibacterial action, sophoraflavanone G was isolated from Sophora exigua, thereafter its effect on membrane fluidity was studied using model membranes and compared with less active naringenin lacking 8-lavandulyl and 2'-hydroxyl groups. Highly purified sophoraflavanone G of 0.05-5 microg/ml, corresponding to the minimum growth inhibitory concentrations against various bacteria, significantly increased fluorescence polarization of the liposomes prepared from 1,2-dipalmitoyl-L-alpha-phosphatidylcholine and 1-palmitoyl-2-oleoyl-L-alpha-phosphatidylcholine. Such increases were found in both liposomes measured with two fluorescent probes to indicate an alteration of membrane fluidity in hydrophilic and hydrophobic regions, suggesting that sophoraflavanone G reduces the fluidity of outer and inner layers of membranes. Although naringenin also showed the membrane effect, it needed concentrations over 2.5 microg/ml to induce a significant reduction of membrane fluidity. Sophoraflavanone G is considered to exert an antibacterial effect by reducing the fluidity of cellular membranes.

中文翻译：

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分离自Sophora exigua的抗菌素Sophoraflavanone G降低膜的流动性。

槐黄酮G（5,7,2'，4'-四羟基-8-薰衣草酮基黄酮）被称为具有强抗菌活性的植物化学物质。为了阐明抗菌作用的药理机制，从槐豆中分离出槐黄酮G，然后使用模型膜研究其对膜流动性的影响，并与缺乏8-lavandulyl和2'-羟基的不太活跃的柚皮素进行比较。0.05-5 microg / ml的高纯度槐豆黄酮G（对应于针对各种细菌的最小生长抑制浓度）显着提高了由1,2-二棕榈酰基-L-α-磷脂酰胆碱和1-棕榈酰基-2-制备的脂质体的荧光偏振油酰基-L-α-磷脂酰胆碱。在用两种荧光探针测量的两种脂质体中均发现了这种增加，表明亲水性和疏水性区域的膜流动性发生了变化，这表明槐豆黄酮G降低了膜外层和内层的流动性。尽管柚皮苷还显示出膜作用，但它需要超过2.5微克/毫升的浓度才能引起膜流动性的显着降低。槐花黄酮G被认为通过减少细胞膜的流动性而发挥抗菌作用。5 microg / ml导致膜流动性显着降低。槐花黄酮G被认为通过减少细胞膜的流动性而发挥抗菌作用。5 microg / ml导致膜流动性显着降低。槐花黄酮G被认为通过减少细胞膜的流动性而发挥抗菌作用。