Flavonoids and xanthones from Maclura cochinchinensis (Lour.) Corner. and their antibacterial activity

Maclura cochinchinensis (Lour.) Corner. has been used widely in traditional medicine, especially for the treatment of rheumatism, hepatitis, and neuralgia [1]. Previous phytochemical investigations of M. cochinchinensis resulted in the identification of a number of isoflavones, flavanones, and xanthones; many of these compounds exhibited interesting biological activities [1], [2]. As part of an ongoing investigation for bioactive compounds from Thai medicinal plants, the fruit and leaf extracts of M. cochinchinensis were examined and these showed good antimicrobial activities with minimum inhibitory concentration (MIC) values in the range of 10 – 160 µg/mL. This prompted us to further investigate their phytochemicals and antimicrobial activities. The leaf and fruit extracts of M. cochinchinensis (Lour.) Corner were separately subjected to silica gel column chromatography to afford four new isoflavones, one new flavone, and 24 known compounds [3]. The structures of the new compounds were characterized by spectroscopic methods and mass spectrometry. All new isoflavones were 5,7,4′-oxygenated isoflavones containing a modified isoprenyl unit at C-8 except for macluracochinone A has a modified isoprenyl unit at C-6. A new flavone was a 2,5,7, 4′-oxygenated flavone, which contained an oxyisoprenyl unit at C-7 and an isoprenyl unit C-5'. All known compounds were eighteen isoflavones, one flavone, one flavanone, and four xanthones. Most of these compounds had one or two isoprenyl units. The antimicrobial activities of 12 of these compounds were evaluated. Of these, gancaonin M, lupiwighteone, lupalbigenin, warangalone, auriculatin, and millexatin F displayed good antibacterial activities against Gram-positive bacteria with MIC values in the range of 1 – 8 µg/mL [3].

Publikationsverlauf

Artikel online veröffentlicht:
12. Dezember 2022

• References

• 1 Nakashima K, Tanaka T, Murata H. et al. Xanthones from the roots of Maclura cochinchinensis var. gerontogea and their retinoic acid receptor-α agonistic activity. Bioorg Med Chem Lett 2015; 25: 1998-2001
• 2 Chien TV, Anh NT, Thanh NT. et al. Two new prenylated isoflavones from Maclura cochinchinensis collected in Hoa Binh province Vietnam. Nat Prod Res 2019; 33: 212-218
• 3 Polbuppha I, Suthiphasilp V, Maneerat T. et al. Macluracochinones A–E, antimicrobial flavonoids from Maclura cochinchinensis (Lour.) Corner. Phytochemistry 2021; 187: 112773