Abstract The hepatoprotective potential of alcesefoliside (AF) from Astragalus monspessulanus was investigated. Iron sulphate/ascorbic acid (Fe2+/AA) lipid peroxidation was induced in rat liver microsomes and pre-incubated with AF and silybin (100, 10 and 1 µmol). Pronounced effects were observed in 100 µmol. In vivo experiments were carried out on rats, challenged orally with carbon tetrachloride (CCl4) alone and after pre-treatment and followed by curative treatment with AF (10 mg/kg). The activity of the serum and antioxidant enzymes, together with reduced glutathione (GSH) levels and malonedialdehyde (MDA) quantity were measured. Microsomal incubation with Fe2+/AA increased MDA production. The pre-incubation with AF reduced the formation of MDA, comparable to silybin. These findings were supported by the in vivo study where CCl4-induced liver damage was discerned by significant increase in serum enzymes and in MDA production as well as by GSH depletion and reduced antioxidant enzymes activity. The AF pre-treatment and consecutive curative treatment normalizes the activity of the serum and antioxidant enzymes alike, as well as the levels of GSH and MDA. Histological examination of AF-treated livers showed a decrease in the abnormal accumulation of lipids in hepatocytes as well as reduced alterative changes in their structure in a model of CCl4-induced toxicity.

The phytochemical content of some Astragalus species distributed in Bulgarian flora has been previously studied. Among other compounds, flavoalkaloids, acylated flavonoids, flavonoid triglycosides and cycloartane saponins have been isolated so far. The composition of the rest of the representatives of this genus in Bulgaria is not explored yet. The aim of this study was to perform a screening for the presence of selected rare secondary metabolites (flavoalkaloids, acylated flavonoids, flavonoid triglycosides and cycloartane saponins) in selected Astragalus species. Samples were collected in different phenological stages and from different locations in the country. A novel and rapid ultra-high performance liquid chromatography – high resolution electrospray ionisation mass spectrometry (UHPLC-HRESIMS) method was developed and applied. For the first time a flavoalkaloid glycoside was determined from extracts of A. onobrychis var. chlorocarpus and A. glycyphylloides. From A. depressus an acylated derivative of kaempferol was newly identified. The flavonol triglycosides camelliaside A, alcesefoliside and mauritianin were proved in samples of A. glycyphylloides, A. onobrychis var. chlorocarpus and A. cicer for the first time as well.

ABSTRACT This study investigated the possible antioxidant and neuroprotective effects of alcesefoliside, isolated from Astragalus monspessulanus L., Fabaceae, against carbon tetrachloride (CCl4)-induced brain injury in Wistar rats. Iron sulphate/ascorbic acid lipid peroxidation was induced in rat brain microsomes and pre-incubated with alcesefoliside and silybin. Male rats were treated in vivo with alcesefoliside and with silymarin alone; animals challenged with CCl4; and pre-treated with alcesefoliside or silymarin in respective doses for 7 days, challenged with CCl4, followed by curative treatment (additional 14 days). The activity of acetylcholine esterase and the antioxidant enzymes: superoxide-dismutase, catalase, glutathione-peroxidase, glutathione reductase and glutathione-S-transferase as well as the biomarkers of oxidative stress malondialdehyde and reduced glutathione were measured. The alcesefoliside pre-treatment and consecutive curative treatment normalizes the activity of the antioxidant enzymes as well as levels of malondialdehyde and reduced glutathione. The observed effects on tissue level correlate with the histopathological observations of the brain. They were comparable to the effects of silymarin, used as a positive control. The results showed that alcesefoliside has a neuroprotective effect against CCl4-induced brain toxicity in rats.

Phytochemical studies of ethyl acetate extracts from the roots and aerial parts of Gypsophila trichotoma revealed the presence of stigmast-7-en-3-ol, stigmasta-7,22-dien-3-ol (spinasterol), ergost-7-en-3-ol, stigmasta-3,5dien7-one, β-sitosterol, 22,23-dihydrospinasterone, vitexin, orientin, homoorientin and hyperoside. The structures of the compounds were determined by GC/MS and HPLC analyses.

Nine flavonoids were identified in aerial parts of Astragalus corniculatus Bieb. (Fabaceae) by liquid chromatography coupled with ionspray mass spectrometry in the tandem mode (LC/MS/MS) with negative ion detection. Vitexin, orientin and eriodictyol-7-O-glucoside are obtained for the first time in genus Astragalus L, and isorhamnetin-3-O-glucoside in the species.