Flavonol Glycosides in Currant Leaves and Variation with Growth Season, Growth Location, and Leaf Position

Abstract

Flavonol glycosides (FG) were analyzed in the leaves of six currant cultivars (Ribes spp.) with HPLC-DAD, HPLC-MS/MS, and NMR. The average amounts of the 12 major, identified FG constituted 86-93% (9.6-14.1 mg/g DW) of the total of 27 FG found. Quercetin and kaempferol were the major aglycones with trace amounts of myricetin. Quercetin-3-O-(2,6-α-dirhamnopyranosyl-β-glucopyranoside), quercetin-3-O-(2-β-xylopyranosyl-6-α-rhamnopyranosyl-β-glucopyranoside), and kaempferol-3-O-(3,6-α-dirhamnopyranosyl-β-glucopyranoside) were identified for the first time in currant leaves and existed in a white currant cultivar 'White Dutch' only. Kaempferol-3-O-β-(6'-malonyl)glucopyranoside was also a new compound existing in abundance in five cultivars but not in the white one. The results show the primary importance of the genetic background of the cultivars. The content of malonylated FG of special importance in cardiovascular health decreased regularly during summer. Time of collection and leaf position were more prominent factors affecting the composition than were the year of harvest or the growth latitude. Randomly collected leaves differed in their FG profiles from those collected from the middle position of new branches.

Phenolic compounds in black currant leaves – an interaction between the plant and foliar diseases?

“…All these compounds have been previously reported in the leaves of black currant (Oszmiański et al 2011;Vagiri et al 2012). The results here agree with previous findings of black currant leaves being a rich source of bioactive phenolic compounds, particularly hydroxycinnamic acids, and flavonols as well as procyanidins (Tabart et al 2006;Ehrhardt et al 2013;Vagiri et al 2015;Yang et al 2015). As to specific phenolic compounds, particularly epigallocatechin, chlorogenic acid, quercetin-3-6-malonylglucoside, quercetin-3-O-glucoside, quercetin-3-O-rutinoside and kaempferol-malonylglucoside were among the most abundant in this study.…”

Non‐targeted metabolite profiling highlights the potential of strawberry leaves as a resource for specific bioactive compounds

“…Agricultural and food industry by‐products constitute an abundant resource of bioactive and functional ingredients, including natural antioxidants and antimicrobial compounds that are potentially applicable in products of the food, pharmaceutical and cosmetic industries . Leaves are one of the largest side streams of berry fruit production, and their enhanced utilization level would be beneficial in improving the sustainability of agricultural practices . Furthermore, intelligent utilization of this ‘waste material’ may bring added value at both ends of the production chain: from primary production of crops to functional food or non‐food applications.…”

“…strawberry ( Fragaria × ananassa ), currants ( Ribes spp. ), raspberry ( Rubus ideaus ), honeysuckle ( Lonicera kamtschatica ), lingonberry ( Vaccinium vitis‐idaea ), apple ( Malus domestica ), chokeberry ( Aronia melanocarpa ), cranberry ( Vaccinium macrocarpon ), bilberry ( Vaccinium myrtillus ) and saskatoon ( Amelanchier alnifolia ) …”

“…Cultivation, storage and processing conditions, harvesting season as well as the genetic background of the plant source affect the chemical composition of by‐product‐based raw materials . Hence product standardization sets a real challenge, especially when the plant material represents varying cultivars and is collected from several locations .…”

“…1 -3 Leaves are one of the largest side streams of berry fruit production, and their enhanced utilization level would be beneficial in improving the sustainability of agricultural practices. 3 Furthermore, intelligent utilization of this 'waste material' may bring added value at both ends of the production chain: from primary production of crops to functional food or non-food applications. It has been reported that leaves of berries and fruits are rich in putatively bioactive polyphenols: high concentrations of polyphenols have been measured from leaves of e.g.…”