Flavonoids, synthesized by plants across all families and therefore found in a huge variety, possess a diverse range of pharmacological properties. Direct antibacterial and synergistic activities as well as the inhibition of several bacterial virulence factors are known. Besides the mode of action, it is important to understand the structure-activity relationship to identify key structural characteristics.

This study aimed to identify biflavonoids with antibacterial activity from Schinus terebinthifolius Raddi fruits. The purified biflavonoids were characterized in terms of their antibacterial effects. We found that the activity of biflavonoids, including agathisflavone (AGF), amentoflavone (AMF), dihydroamentoflavone (DHAF) and tetrahydroamentoflavone (THAF), was dependent on their chemical configuration and degree of oxidation, with THAF showing the highest activity on planktonic cells. Additionally, biofilm formation and composition were strongly influenced by THAF.

Even slight differences in the chemical structure have fundamental effects on the activity of isolated biflavonoids. This suggests a specific binding of these substances in bacteria and thus enables detailed investigations of the mode of action in the future.

黄酮类化合物由所有科室的植物合成，因此种类繁多，具有多种药理特性。直接的抗菌和协同活性以及对几种细菌毒力因子的抑制是已知的。除了作用方式外，重要的是了解结构与活性的关系，以识别关键的结构特征。

这项研究的目的是从中华绒螯蟹（Schinus terebinthifolius Raddi）果实中鉴定具有抗菌活性的双黄酮类化合物。纯化的类黄酮具有抗菌作用。我们发现双黄酮类化合物的活性取决于龙虾的化学构型和氧化程度，包括agathisflavone（AGF），amentoflavone（AMF），dihydroamentoflavone（DHAF）和tetrahydroamentoflavone（THAF），其中THAF对浮游细胞的活性最高。此外，生物膜的形成和组成受到THAF的强烈影响。

化学结构即使有微小差异，对分离出的双黄酮类化合物的活性也有根本影响。这表明这些物质在细菌中具有特异性结合，因此可以在将来对作用方式进行详细研究。