Oxygen activation by photoexcited protoberberinium alkaloids from Mahonia aquifolium

Abstract

Protoberberinium salts, i.e. berberine (I), palmatine (II) and jatrorrhizine (III) prepared from Mahonia aquifolium (Pursh) Nutt. belong to isoquinoline alkaloids possessing interesting biological activity (e.g. antibacterial, antimalarial, antitumor). The characteristic UV/Vis absorption band maxima of I-III iodide salts were found in regions 350 and 425 nm in dimethylsulfoxide (DMSO) and ethanol solvents, and were only negligibly influenced by substitution changes on the C-2 and C-3 positions. The fluorescence intensity of protoberberinium salts monitored in ethanol solutions was significantly lowered by iodide counter-ions, and decreased in the order berberine > palmatine > jatrorrhizine. EPR spectroscopy supplied evidence of the formation of super-oxide anion radicals and singlet oxygen upon irradiation of berberine in oxygenated DMSO solvent. The photochemical generation of O(2) (.-) and (1)O(2) in DMSO solutions of palmatine and jatrorrhizine was substantially lower, and probably reflected the replacement of a photolabile methylenedioxy group at C-2 and C-3 positions in the berberine molecule by two methoxy groups in palmatine, and methoxyl (C-2) and hydroxyl (C-3) substitution in jatrorrhizine. Additionally, the powder EPR spectra of protoberberinium iodides I-III measured at 290 K revealed the presence of single-line EPR signals (g(eff) = 2.0044), which were attributed to hydroperoxidic structures produced by the autoxidation process. The photochemical reactions of protoberbenium salts producing reactive oxygen species after UVA excitation should be integrated in biological activity investigations, as well as in their applications in skin disorder treatment.

UPLC‐MS/MS Profile of Alkaloids with Cytotoxic Properties of Selected Medicinal Plants of the Berberidaceae and Papaveraceae Families

“…Methyl-hernovine was detected for the first time in G. flavum and columbamine in B. thunbergii . According to literature data, columbamine occurs in C. cava [ 24 ] and M. aquifolium [ 25 ] which was not confirmed in this study. Methyl-corypalmine was detected in F. officinalis for the first time.…”

“…In this study, the presence of fumarophycine [ 26 ] and corydamine [ 27 ] in this plant material was confirmed. The presence of jatrorrhizine in M. aquifolium [ 25 ] and corydaline in C. cava [ 28 , 29 ] was also confirmed, but not in F. officinalis [ 27 ]. Corydine and tetrahydropalmatine were found in this study only in C. cava but were not in other investigated plant species.…”

Transcriptional profile of theShigella flexneriresponse to an alkaloid: berberine

“…Alkaloids are photosensitive molecules that can induce the production of superoxide and singlet oxygen upon irradiation in the UVA region (Hudson & Towers, 1991; Brezova et al ., 2004). Although artificial light sources emitting UVA were not used in our experiment, we found that a variety of superoxide‐inducible genes were upregulated by BC (Table S2).…”

Antiinflammatory effect of the ethanol extract of Berberis koreana in a gerbil model of cerebral ischemia/reperfusion

“…Various isoquinoline alkaloids are used as traditional medicines in the Orient because of their immunomodulatory, antiinflammatory and antibacterial effects (Brezová et al, 2004;Jantan et al, 2006). In addition, they decrease the activity of elastase reductions in which are known to be associated with inflammatory disease and the development of arthritis (Tanaka et al, 1993).…”