In conclusion, this study systematically investigated the
phenolic composition of 28 pigmented edible bean coats and their
antioxidant and antibacterial effects. These bean coat extracts had
relatively high level of total phenolics and antioxidant effect, and
most of them also exhibited antibacterial effects, generally higher
than phenol and with specificity against gram-positive bacteria.
Flavonoids and proanthocyanidins should be the main polyphenols
in these pigmented bean coats and responsible for their
antioxidant and antibacterial effects. As a result, pigmented bean
coats rich in polyphenols can be a good source of natural antioxidant
and antibacterial agents with potential application as food
preservatives