Melianone, the protolimonoid (24, 25-epoxyflindissone), was isolated from the medicinal tree species, Swietenia mahagoni (L.) JACQ (Meliaceae). The compound isolated from petroleum ether leaf extracts (5.39%) was quantified using high-performance thin-layer chromatography (HPTLC) method. In antimicrobial assays melianone inhibited Salmonella ser. Typhi with an MIC of 0.053 µM. Induced Fit Docking (IFD) of the ligand, melianone, with proteins involved in anaerobic virulence of the pathogen, revealed that it binds with FocA (a transport protein of formate ions) at its “periplasmic opening” with a glide energy of − 51.8576 kcal mol⁻¹. Melianone altered the overall conformation of the protein (protomer A) by 0.347 Å RMSD. It induced a notable protein topology (Ω loop region) shift in the channel from an intermediate-open to a closed-state conformation and was supported by molecular dynamic simulations performed. FocA, a protein that contributes to its survival under anaerobic conditions, was further evaluated experimentally, after exposure of Salmonella ser. Typhi to melianone, resulting in the altered homeostasis of formate.

Melianone 是一种原柠檬苦素 (24, 25-epoxyflindissone)，是从药用树种Swietenia mahagoni (L.) JACQ（楝科）中分离出来的。使用高效薄层色谱 (HPTLC) 方法对从石油醚叶提取物中分离出的化合物 (5.39%) 进行定量。在抗菌测定中，melianone 抑制沙门氏菌。伤寒杆菌的 MIC 为 0.053 µM。配体 melianone 与参与病原体厌氧毒力的蛋白质的诱导契合对接（IFD）显示，它在其“周质开口”处与 FocA（甲酸离子转运蛋白）结合，滑动能量为 − 51.8576 kcal摩尔^-1 。 Melianone 使蛋白质（原体 A）的整体构象改变了 0.347 Å RMSD。它诱导通道中显着的蛋白质拓扑结构（Ω环区域）从中间开放构象转变为闭合状态构象，并得到分子动力学模拟的支持。 FocA 是一种有助于其在厌氧条件下生存的蛋白质，在接触沙门氏菌血清后，通过实验进一步评估了 FocA。伤寒菌转化为二甲酮，导致甲酸的稳态改变。