Abstract
Anchusa italica
Retz has been used for a long time in phytotherapy. The aim of the present study was to determine the antioxidant and antibacterial activities of extracts from the leaves and roots of
Anchusa italica
Retz. We first determined the content of phenolic compounds and flavonoids using Folin–Ciocalteu reagents and aluminum chloride (AlCl
3
). The antioxidant activity was determined using three methods: reducing power (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant capacity (TAC). The antimicrobial activity was investigated against four strains of
Escherichia coli,
two strains of
Klebsiella pneumoniae
and coagulase-negative
Staphylococcus,
and one fungal strain of
Candida albicans.
The results showed that the root extract was rich in polyphenols (43.29 mg GAE/g extract), while the leave extract was rich in flavonoids (28.88 mg QE/g extract). The FRAP assay showed a strong iron reduction capacity for the root extract (IC
50
of 0.11 µg/mL) in comparison to ascorbic acid (IC
50
of 0.121 µg/mL). The DPPH test determined an IC
50
of 0.11 µg/mL for the root extract and an IC
50
of 0.14 µg/mL for the leaf extract. These values are low compared to those for ascorbic acid (IC
50
of 0.16 µg/mL) and BHT (IC
50
0.20 µg/mL). The TAC values of the leaf and root extracts were 0.51 and 0.98 mg AAE/g extract, respectively. In vitro, the extract showed inhibitory activity against all strains studied, with diameters of zones of inhibition in the range of 11.00–16.00 mm for the root extract and 11.67–14.33 mm for the leaf extract. The minimum inhibitory concentration was recorded for the leaf extract against
E. coli
(ATB:57), corresponding to 5 mg/mL. Overall, this research indicates that the extracts of
Anchusa italica
Retz roots and leaves exert significant antioxidant and antibacterial activities, probably because of the high content of flavonoids and polyphenols.