Bioactivity-guided isolation of compounds from Sophora flavescens with antibacterial activity against Acinetobacter baumannii

Abstract

Bioactivity-guided fraction of an extract of Sophora flavescens to identify antibacterial compounds against Acinetobacter baumannii, led to the isolation of two new compounds, (2″R)-5-methoxy-7-hydroxy-8-lavandulylchromone ( 13) and (2S,βS)-(-)-sophobiflavonoid CE (19), and 18 known flavonoids, (6aR,11aR)-(-)-maackiain (1), (2S)-(-)-8-prenylnaringenin (2), (2S)-(-)-exiguaflavanone K (3), (2S)-(-)-sophoraflavanone G (4), (2S)-(-)-leachianone A (5), (2S)-(-)-kushenol E (6), (2S)-(-)-leachianone G (7), (±)-kushenol F (8), (2S)-(-)-kurarinone (9), (2S)-(-)-kurarinol (10), (2R,3R)-(+)-3,7,4'-trihydroxy-5-methoxy-8-prenylflavanone (11), (2S)-(-)-isoxanthohumol (12), (2S)-(-)-2'-methoxykurarinone (14), (2R,3R)-(+)-kushenol I (15), calycosin (16), kuraridin (17), (2S)-(-)-kushenol A (18), and trifolirhizin (20). Their structures were elucidated based on NMR, MS, and CD spectroscopic analysis. Among them, 1, 2, 5, and 15 exerted modest antibacterial activity against A. baumannii, with MIC 95 of 128-256 μg/mL for 2 and 256-512 μg/mL for 1, 5 and 15.

A Novel Splice Variant of BCAS1 Inhibits β-Arrestin 2 to Promote the Proliferation and Migration of Glioblastoma Cells, and This Effect Was Blocked by Maackiain

“…MK is isolated from the traditional Chinese herbal medicine Kushen (dried roots of Sophora flavescens Aiton) [ 80 ]. MK has been reported to have multiple pharmacologic properties, such as anti-allergic [ 81 , 82 ], anti-inflammatory [ 44 , 83 ], anti-oxidative [ 44 ], anti-obesity [ 84 ], and antibacterial [ 85 ] activity in addition to neuroprotection [ 86 , 87 ]. In cancer therapy, MK can hinder the proliferation, migration, invasion, and foci formation of triple-negative breast cancer cells and thus has a significant inhibitory effect on tumor growth.…”

Antimicrobial activities of lavandulylated flavonoids in Sophora flavences against methicillin-resistant Staphylococcus aureus via membrane disruption

“…The root of Sophora flavescens , also known as Kushen (Radix Sophorae Flavescentis), is commonly used to treat skin diseases and bacterial diarrhea in China and other Asian countries [21] , [22] . Previous studies have found that S. flavescens contains abundant alkaloids and flavonoids, which showed excellent antibacterial activity [23] , [24] . Sophoraflavanone G (SFG) and kurarinone (KE) are two representative lavandulylated flavonoids with the highest content in S. flavescens .…”

“…Sophoraflavanone G (SFG) and kurarinone (KE) are two representative lavandulylated flavonoids with the highest content in S. flavescens . Both showed potent antibacterial activity with a minimum inhibitory concentration (MIC) or fractional inhibitory concentration (FIC) <10 μg/mL and have a synergistic effect with common antibiotics [24] , [25] , [26] , [27] . They have been reported to inhibit bacterial growth by reducing the fluidity of cell membranes [28] .…”