Untargeted metabolomics and in vitro functional analysis unravel the intraspecific bioactive potential of flowers from underexplored Camellia japonica cultivars facing their industrial application
The Camellia genus comprises a vast array of underexplored medicinal plants that merit a systematic valorization
to exploit their potential as natural sources of phytochemicals with associated health-promoting properties. In
this work, flower extracts from eight poorly characterized Camellia japonica L. cultivars were subjected to
polyphenol profiling through untargeted metabolomics combined with in vitro functional analysis. Anthocyanins,
mostly represented by cyanidin 3-O-glycosides, flavones, and flavonols, were found as the major constituents of
C. japonica flowers, together with hydroxycinnamic acids, tyrosols, alkylphenols, and stilbenes, which were
detected for the first time in this species. The application of multivariate statistics revealed a flower colordependent
fingerprint of C. japonica cultivars, featuring anthocyanins and other flavonoids as metabolite
markers associated with color-flowered cultivars with respect to white-flowered ones. The accumulation of anthocyanins,
especially reported in ‘Eugenia de Montijo’ flowers, was highly correlated with the cytotoxic and
anti-inflammatory properties of the derived extracts, including AGS, Caco-2, and MCF7 cancer cell lines.
Moreover, the flavones accumulation reported in ‘Carolyn Tuttle’ extracts was also associated with high rates of
free-radical scavenging activity, as well as a potent cytotoxicity against the Caco-2 cell line. In general,
C. japonica anthocyanin-enriched flower extracts were revealed as promising candidates for the industrial production
of polyphenols with associated biological activities of high interest for critical sectors in the food,
pharmaceutical, and cosmetic industries.
