Purpose: To characterise the phytochemical profile of whole plants of
Centaurea balsamita
, C.
depressa
and
C. lycopifolia with LC-ESI-MS/MS, and as well as their antioxidant, anticholinesterase and
antimicrobial activities.
Methods: Organic and aqueous extracts of the three
Centaurea
species were evaluated for DPPH free
radical, ABTS cation radical scavenging and cupric reducing antioxidant capacity (CUPRAC). Acetyland
butyryl-cholinesterase enzyme inhibition abilities of the extracts using petroleum ether, acetone,
methanol and water were studied to determine anticholinesterase activity, while antimicrobial activity
was determined by disc diffusion method using appropriate antimicrobial standards and organisms. The
phytochemical components of the methanol extracts were assessed by LC-MS/MS.
Results: The methanol extract of
C. balsamita exhibited much higher DPPH free and ABTS cation
radicals scavenging activities (with IC
50 of 62.65 ± 0.97 and 24.21 ± 0.70 mg/ml, respectively) than the
other extracts. The petroleum ether extracts of the plant species exhibited moderate inhibitory activity
against butyrylcholinesterase enzymes while the acetone extract of
C. balsamita showed good
antifungal activity against Candida albicans. Quinic acid (17513 ± 813 μg/g, 63874 ± 3066 μg/g and
108234 ± 5195 μg/g) was the major compound found in the methanol extracts of
C. balsamita,
C.
depressa and
C. Lycopifolia, respectively.
Conclusion: These results indicate quinic acid is the major compound in the three plant species and
that
Centaurea balsamita has significant antioxidant, anticholinesterase and antimicrobial properties.
Further studies to identify the compounds in the extracts responsible for the activities are required.
