Isoflavones from Calpurnia Aurea subsp. aurea and their anticancer activity

Area of Science:

• Phytochemistry
• Pharmacology
• Ethnomedicine

Background:

• Calpurnia aurea is an African medicinal plant with documented antibacterial, antioxidant, and insecticidal properties.
• Traditional use in Africa spans various medical conditions, necessitating scientific validation.
• Previous research indicated bioactivity, prompting further investigation into its chemical constituents.

Purpose of the Study:

• To isolate and identify phytochemical constituents from Calpurnia aurea stem and bark.
• To evaluate the in vitro anticancer activity of isolated compounds against human cancer cell lines.
• To provide a scientific rationale for the ethnomedicinal use of Calpurnia aurea.

Main Methods:

• Extraction of plant material using organic solvents of varying polarity.
• Separation and purification of compounds via column chromatography.
• Identification of compounds using Nuclear Magnetic Resonance (NMR) spectroscopy.
• In vitro anticancer screening against breast (MCF7), renal (TK10), and melanoma (UACC62) cell lines.

Main Results:

• Five isoflavones (1-5), a pterocarpan, and a quinolizidine alkaloid (calpurnine) were isolated.
• Isoflavone 5 (3',7-dihydroxy-4',8-dimethoxyisoflavone) exhibited the highest activity across all tested cancer cell lines.
• Isoflavone 2 (7,3'-dihydroxy-5'-methoxyisoflavone) also displayed significant anticancer effects.

Conclusions:

• The isolated isoflavones demonstrated moderate in vitro anticancer activity against renal, melanoma, and breast cancer cell lines.
• Isoflavones 2 and 5 were the most potent among the tested compounds.
• These findings support the ethnomedicinal use of Calpurnia aurea and suggest potential for synergistic effects with existing anticancer therapies.