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Flavonoids are one of the most popular antioxidants in plants. Their varied pharmacological activities are important for these com)pounds in order to add and to complement conventional therapy. Alcesefoliside and mauritianin are rare flavonol triglycosides, isolated from the overground part of A. monspessulanus subsp. monspessulanus. The aim of the study was to examine the in vitro effects of the isolated flavonoids on the contractility of a. basilaris. Administered alone, at concentration 10 µM, alcesefoliside and mauritianin did not influence the vascular tone of segment of a. basilaris. The combination of both compounds, at 10 µM, revealed an increased response of the vascular tone of a. basilaris. These effects of the flavonoids suggest their possible beneficial effect as further candidates in the complex therapy of neurodegenerative disease. [ABSTRACT FROM AUTHOR]

Effects of increased concentration of calcium chloride on growth and production of flavonoids in newly established shoot and callus Gypsophila glomerata cultures were studied. The highest impact of CaCl2 on the growth index was determined in callus cultures (GI = 0.92), while in shoot cultures calcium treatment reduced the amount of biomass (GI = 0.38). Total flavonoids in shoot cultures grown on MS medium and MS medium supplemented with double amount of CaCl2 were 0.36 mg/g d. w. In both callus cultures, 2 mg/g d. w. total flavonoids were quantified. Shoots and callus grown on non-modified media accumulated 0.02 mg/g d. w. quercetin derivatives. Unlike these, both shoots and callus grown on calcium-enriched media accumulated 0.03 and 0.05 mg/g d. w. of isorhamnetin derivatives. In vitro shoot cultures grown on MS medium enriched in twice the amount of CaCl2 accumulated the highest amount of saponarin (0.138 mg/mg d. w.). [ABSTRACT FROM AUTHOR]

Astragalus hamosus contains valuable biologically active compounds, incl. flavonoids. The possibility for in vitro cultivation of the species as a source of important flavonoids was studied. Shoot and callus cultures were established and successfully cultivated on different nutrition media, complemented or not with growth regulators. An ultra-high performance liquid chromatography – high-resolution electrospray ionisation mass spectrometry (UHPLC-HRESIMS) qualitative and quantitative analysis of non-purified methanol extracts of these cultures was performed. It was found that the cultures produced rutin in comparable quantity. Interestingly, both shoots and callus cultures accumulated the rare triglycosides alcesefoliside and mauritianin. The quantity of mauritianin, biosynthesized in shoots, was significantly higher to that in callus cultures. Alcesefoliside, was in lower quantity, compared to mauritianin. In addition, callus cultures produced alcesefoliside trice as the shoots, besides their lower level of differentiation. These findings could serve as initial research to establish the value of in vitro cultures from A. hamosus as an alternative mean of production of pharmaceutically important flavonol glycosides. [ABSTRACT FROM AUTHOR]

A new tetracyclic saponin, 17(R),20(R)-3β,6α,16β-trihydroxycycloartanyl- 23-carboxylic acid 16-lactone 3-O-β-D-glucopyranoside (1) together with one known flavonoid, camelliaside A (2) were isolated from the aerial parts of Astragalus glycyphyllos L. Their structures were determined by chemical, HRESIMS and NMR methods. On 6-hydroxydopamine in vitro model on isolated rat brain synaptosomes, compounds 1-2 had statistically significant neuroprotective activity similar to that of Silibinin, tested at 100 lM. Saponin 1 possessed the most prominent neuroprotective and antioxidant effects in this in vitro model. On human recombinant monoamine oxidase type B enzyme compound 1 displayed strong inhibiting activity, compared to Selegiline (1 lM). It could be concluded that the new epoxycycloartane saponin 1 could be a promising leading structure in respect of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

This study investigated the possible hepato- and neuroprotective effects of flavoalkaloids and flavonoids isolated from Astragalus monspessulanus ssp. monspessulanus and ssp. illyricus. Rat hepatocytes obtained by in situ two-stepp collagenase perfusion, and rat brain synaptosomes obtained by multiple centrifugation and Percoll gradient were used. Administered alone, on hepatocytes, all of the compounds increased statistically significantly the lactate dehydrogenase (LDH) activity and malondialdehyde (MDA) production and decreased the reduced glutathione (GSH) level, compared to the control (non-treated hepatocytes). Some of the compounds (1–7) had lower toxicity on the exam parameters than silybin. The main structural features accounting for the lower hepatotoxicity (evaluated by quantitative structure–activity relationship (QSAR) studies) are the increased number of hexoses and the number of aromatic OH groups. On the two in vitro toxicity models, all the 13 compounds had statistically significant hepato- and neuroprotective activities. They preserved the hepatocyte and synaptosome viability, as well as the GSH level and decreased the LDH leakage and MDA production. On isolated rat hepatocytes, in tert-butyl hydroperoxide- and on isolated rat synaptosomes, in 6-OH-dopamine-induced oxidative stress, flavoalkaloids and flavonoids isolated from A. monspessulanus ssp. monspessulanus and ssp. illyricus, were effective hepato- and neuroprotectors, as well as antioxidants. The observed higher hepato- and neuroprotective effects of 1, 2, 4, 7 and eight may be assigned to the different substituents present in either the aglycone or the sugar moieties. [ABSTRACT FROM AUTHOR]