Kaempferitrin: A Flavonoid Marker to Distinguish Camellia oleifera Honey

C. oleifera is an economically important oilseed crop and medical plant. However, as a characteristic honey resource, the standard protocol used to identify the composition of C. oleifera honey has not been established yet. Previously, distinctive flavonoid has been shown as an effective marker to trace the botanical origin of honey. In this study, we examined the flavonoid types in C. oleifera honey and nine other monofloral honeys by using liquid chromatography tandem-mass spectrometry (LC-MS/MS) and compared the differences and identified eight distinct flavonoids in C. oleifera honey. Then, comparing the 8 flavonoids with the 14 flavonoids common to C. oleifera honey and nectar, two distinct flavonoids were identified in C. oleifera honey and nectar. Finally, we identified kaempferitrin as the distinct flavonoid marker in C. oleifera honey using the degree of influence of the partial least-squares discriminant analysis (PLS-DA) model on C. oleifera honey and ployfloral honey.