A Study on the Antioxidant and Antimicrobial Properties of the Aerial Parts Extract of Lagerstroemia indica L.

This research aimed to investigate the antioxidant and antimicrobial properties of the extract of the medicinal plant Lagerstroemia indica L. against bacteria, including Staphylococcus aureus, Escherichia coli, Salmonella typhi murium, Streptococcus mutans, and fungi, including Aspergillus flavus and Candida albicans. The study also evaluated the extract's activities in inhibiting the free radical DPPH, total phenols and flavonoids. The L. indica L. plant was collected from the medicinal plant garden of the Islamic Azad University, Ayatollah Amoli branch. In this research, two varieties with purple and pink flowers, and their leaves were used for extraction. The extraction process was performed using the maceration method and a rotary evaporator. The extract's antimicrobial and antioxidant activities were found to be higher in the extract of purple flowers compared to pink flowers. S. aureus and Aspergillus flavus showed the highest sensitivity to the extract of purple flowers compared to other extracts, with a minimum inhibitory concentration of 12.5 and 25 g/ml for antimicrobial activity and a minimum concentration of 25 and 50 g/ml for fungicidal activity, respectively. The average total phenol content in the extract of purple flowers was 369.23 mg of gallic acid equivalent per gram of extract. The average flavonoid content in this extract was 24.1 mg of gallic acid equivalent per gram of extract. In the investigation of the percentage of DPPH free radical scavenging activity, concentrations of 400 g/ml of purple flower extract had the highest average inhibition percentage of 83.97%, while concentrations of 6.25 g/ml had the lowest average inhibition percentage of 22.481%. Given its high antioxidant activity and rich content of phenolic compounds, it can be said that extracts derived from this plant exhibit inhibitory and bactericidal effects against the studied microorganisms and can be used as an antimicrobial compound.

A Study on the Antioxidant and Antimicrobial Properties of the Aerial Parts Extract of Lagerstroemia indica L. Keywords:

Lagerstroemia indica L , Antimicrobial , Antioxidant , total phenol , flavonoid