Bioactive potential of Rosa micrantha Borrer ex Sm. and Castanea sativa Mill. flowers as functional food ingredients: antioxidant and antifungal activity
Conference Paper
Overview
Overview
abstract
Natural products represent a rich source of biologically active compounds and are an
example of molecular diversity, with recognized potential in drug discovery and
development. Particularly, the plant kingdom offers a wide range of natural
antioxidants, recognized by having remarkable medicinal properties [1,2]. These
beneficial effects could be related to the high content in phenolic compounds, known
for being strong scavengers of free radicals, which have key roles in ageing and various
diseases, such as coronary heart disease, cancer or neurodegenerative diseases [3].
Phenolic compounds of Castanea sativa Mill. and Rosa micrantha Borrer ex Sm.
flowers from Northeastern Portugal were characterized by our research group using
HPLC-DAD-ESI/MS. Furthermore, it was performed a screening of their antifungal
potential against Candida species (C. albicans, C. glabrata, C. parapsilosis and C.
tropicalis) and the antioxidant activity was accessed by four in vitro assays: scavenging
effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals, reducing power (ferricyanide
Prussian blue assay), inhibition of β-carotene bleaching and inhibition of lipid
peroxidation in brain cell homogenates by TBARS (thiobarbituric acid reactive
substances) assay. The detailed results and all the authors that contributed to the studies
are available in references [1-3].
Hydrolysable tannins (e.g. tri and digalloyl HHDP glucose) were the main group of
phenolic compounds in C. sativa, while flavonoids (e.g. (+)-catechin and procyanidin
dimers and trimers) were the most abundant group in R. micrantha. Thus, the stronger
effect showed by this latter against all the Candida species and, particularly its fungicide
effects in C. glabrata, might be related to the mentioned flavonoids that were
inexistence in C. sativa sample. Otherwise, C. sativa showed the highest antioxidant
activity (EC50 values between 30-110 μg/mL of extract).
Therefore, these flowers may be incorporated as functional ingredients in food matrices
to promote health benefits, but also to increase the products shelf life, through the
observed antioxidant and antifungal properties.
