3.5. Total flavonoid contents of 23 edible flowers
As shown in Table 4, the total flavonoid contents varied from
0.45 ± 0.01 to 71.49 ± 0.86 mg RE/g with the difference of 158.86-
fold in the initial flavonoid contents. Osmanthus fragrans
(Thunb.) Lour had the highest total flavonoid content, followed
by Lavandula angustifolia Mill, Rosmarinus officinalis
L, Perennial chamomile, and Chamomilia. Gomphrena globosa
Linn had the lowest total flavonoid content among the tested
flowers. Following the gastric phase of the in vitro digestion
model, there was a significant (P < 0.05) decrease in total flavonoid
content of 20 edible flowers. The greatest decrease was
observed in Osmanthus fragrans (Thunb.) Lour with a decrease
from 71.49 ± 0.86 to 46.51 ± 0.89 mg RE/g. After gastric
phase of digestion, although Osmanthus fragrans (Thunb.)
Lour’s total flavonoid content was significantly decreased
(P < 0.05) it still exhibited the highest total flavonoid content
among the tested flowers. Redartfulplum tea was the only one
that had significantly increased total flavonoid content after
the gastric phase of in vitro digestion. After the duodenal phase
of digestion, the total flavonoid contents of 3 edible flowers were
significantly increased (P < 0.05) compared with initial total phenolic
contents, while the total flavonoid contents of 19 edible
flowers were decreased significantly (P < 0.05)