Flavonol quantification and stability of phenolics in fermented extracts from fresh Betula pendula leaves

Conversion of Phenolic Constituents in Aqueous Hamamelis virginiana Leaf Extracts During Fermentation

“…This observation indicated that flavonol glycosides are preferentially converted into their aglycones quercetin and kaempferol. This flavonol glycoside deconjugation has previously been described for fermented birch leaf extracts (Millet et al , ) as well as several other microbiological systems, e.g. deconjugation by colonic microorganisms (Jaganath et al , ; Selma et al , ), by lactic acid bacteria in sourdough (Svensson et al , ) or wine (Hernández et al , ).…”

“…After 7 days, the batch is stored at 15 C in the dark for further maturation (GHP, 2003). According to current conception, these processes are typically catalysed by lactic acid bacteria, especially during the first few days (Millet, 2010;Schwarzenberger et al, 2012). As a consequence, the batch undergoes acidification which leads to growth inhibition of the accompanying microbial flora (Schwarzenberger et al, 2012).…”

“…Aqueous fermented Hamamelis leaf extracts represent a preparation that is rich in tannins as well as flavonols (Duckstein and Stintzing, 2011). However, only scattered data on the fermentation of plant extracts by their own natural microflora exist (Bilia et al, 2007;Millet, 2010;Millet et al, 2010;Schwarzenberger et al, 2012). Therefore, the objective of this study was to monitor aqueous Hamamelis leaf extracts during a fermentation and maturation period of 6 months to expand the picture of fermentative conversion processes on phenolics, especially of hydrolysable tannins and flavonol glycosides.…”

Medicinal plants of the genus Betula—Traditional uses and a phytochemical–pharmacological review

“…Chemotaxonomic and ecological studies have been carried out using rhododendrin, platyphylloside, phenolics and flavonoids Lennart, 1996, 1997;Mämmelä, 2001;Valkama et al, 2003Valkama et al, , 2004Shults et al, 2005;Lahtinen et al, 2006;Stark et al, 2008;Millet et al, 2010;Muilenburg et al, 2011;Liimatainen et al, 2012b).…”

Identification of hyperoside metabolites in rat using ultra performance liquid chromatography/quadrupole-time-of-flight mass spectrometry

“…It was also detected in many plant species such as Abelmoschus manihot [2], Black Currant [3], Rosa agrestis [4], Ligularia fischeri [5][6][7][8][9]. Hyperoside was reported to have antioxidant effect [10][11][12], antidepressant-like effect [13], antiviral activity [14], antifungal activity [15].…”