Summary:
In the context of the research, it was chosen to study the juice of a particular variety of bergamot coming from the island of Kefalonia, from the Vlachata region. The phytochemical analysis of the ethanolic extract of the juice was performed by various chromatographic techniques, such as centrifugal partition chromatography, molecular exclusion chromatography, preparative thin layer chromatography, and high
performance liquid chromatography. This procedure led to the isolation of 14 metabolites that were identified by NMR (1D & 2D) and UHPLC-HRMS spectroscopy.
Seven of them (naringin, neoeriocitrin, neohesperdin, eriodictyol-7-O-glucoside,
pinocembrin-7-O-neoesperidoside, 6’’-malonylnaringin and melitidin) belong to the flavonoid compounds and more precisely they are derivatives of glycosylated flavanones. In addition, two furanocoumarins (bergaptol and 6’-7’-dihydroxybergamottin) as well as three triterpenes (limonin, nomilin and nominilic acid) were indentified. Two others phenolic
derivaties (Picraquassioside A and Abscisic acid) were also indentified.
Finaly, bioligical assays, DPPH (antioxidant activity) and tyrosinase inhibition (whitening activity), were performed, both to the total ethanolic extracts as well as pure molecules. The antibacterial activity of some fractions were also tested against Gram (+) (Micrococcus luteus, Bacillus subtilis, Staphyloccocus aureus) and Gram (-) (Escherichia coli) strains.
Overall this work has shown that two molecules, neoerocitrin anderiodictyol-7-O-glucoside, showed moderate activity against free DPPH, with IC50 = 90.8 μM and 114.4 μM respectively, while the whitening effect did not show any remarkable results. As for the
antimicrobial study, two fractions showed an obvious antimicrobial effect, that are under further investigation.
Bergamot form Kefalonia is a promising source of bioactive compounds and can be further exploited.
Keywords:
Citrus bergamia, bergamot, flavonoids, limonoids, furanocoumarins
