Characterization of Sugar and Polyphenolic Diversity in Floral Nectar of Different ‘Oblačinska’ Sour Cherry Clones

Abstract

'Oblačinska' sour cherry, an autochthonous cultivar, is the most planted cultivar in Serbian orchards. Since fruit trees in temperate zone reward insects by producing nectar which 'quality' affects the efficiency of insect pollination, the aim of this study was analyzing of sugars and polyphenolics in floral nectar of 16 'Oblačinska' sour cherry clones with different yielding potential. The contents of sugars and sugar alcohols were analyzed by ion chromatography, while polyphenolic profile was established using liquid chromatography/mass spectrometry technique. Fourteen sugars and six sugar alcohols were detected in nectar samples and the most abundant were fructose, glucose, and sucrose. Eleven polyphenols were quantified using available standards, while another 17 were identified according to their exact masses and characteristic fragmentations. Among quantified polyphenols, rutin, naringenin, and chrysin were the most abundant in nectar. Principal component analysis showed that some polyphenol components (naringin, naringenin, and rutin) together with sugars had high impact of spatial distribution of nectar samples on score plot.

Phenolic Composition Influences the Health-Promoting Potential of Bee-Pollen

“…An Accela liquid chromatography (LC) system connected to a linear ion trap-Orbitrap hybrid mass spectrometer (LTQ OrbitrapXL, Thermo Fisher Scientific) with heated electrospray ionization (HESI) was used for the identification of flavonoid glycosides in bee-pollen samples. Chromatographic separation and mass spectrometry parameters were same as previously reported by Guffa et al [26].…”

The flavonoid rutin protects the bumble bee Bombus impatiens against cognitive impairment by imidacloprid and fipronil

“…During the first day, we randomly assigned each bee to one of two treatments: (i) 20 µl of 1 mol l −1 sucrose solution twice a day or (ii) 20 µl of 1 μmol l −1 rutin (600 ppb, 12 ng per bee; Sigma-Aldrich R5143) solution dissolved in 1 mol l −1 sucrose solution twice a day. This dosage of rutin (determined after L. M. García, J. J. Sutachan, C. F. Morantes-Ariza, V. Caicedo-Garzón, S. L. Albarracín and A.J.R., unpublished) is within or below the reported concentrations from the field, although there is enormous variation among plant species (1180 ppb in nectar reported by Guffa et al, 2017 ; Gullón et al, 2017 ). Bees received a total of six doses across three consecutive days.…”

Untargeted Metabolomics Analysis of the Orchid Species Oncidium sotoanum Reveals the Presence of Rare Bioactive C-Diglycosylated Chrysin Derivatives

“…The presence of chrysin in propolis and honey strongly suggests that many plant species accumulate chrysins in flowers, probably in the pollen and/or nectar [ 54 , 55 ]. Accordingly, we found that O. sotoanum accumulates high levels of glycosylated chrysins in flowers, reaching bulk levels of 10 mg/g FW.…”