Identification of kaempferol from the leaves of Diospyros kaki and its antimicrobial activity against Streptococcus mutans

Abstract

This paper describes the isolation and identification of an antimicrobial compound against Streptococcus routaris from the leaves of Diospyros kaki. After repeated chromatography of the weakly acidic fraction of acetone extracts, an antimicrobial compound against S. mutans was isolated. The chemical structure of the active compound was elucidated by spectroscopic methods, and identified as kaempferol. Kaempferol is an aglycone of astragalin (kaempferol 3-O β -D-glucopyranoside) which has been isolated from the leaves of D. kaki. The minimum inhibitory concentrations of kaempferol against Streptococcus mutans, Escherichia coli, Bacillus subtilis, and Staphylococcus aureus were estimated.