Antimicrobial properties of Lawsonia inermis (henna): A review

Naphthoquinones are compounds present in various families of plants; their molecular structures endow them with redox properties which confer activity in various biological oxidative processes. In ethnomedicine, plants containing naphthoquinones have been employed for treatment of a number of diseases including cancer. Lawsonia inermis (henna) is widely cultivated and used in many oriental, Middle Eastern and northern African countries. It is best known for its colouring matter contained in the leaves. Henna extract contains lawsone (C10H6O3), the active ingredient and a naturally occurring naphthoquinone. The development of new antimicrobial agents is a research area of utmost importance. Antimicrobial resistance among key microbial pathogens continues to grow at an alarming rate worldwide. The challenge of synthesising derivatives of natural antimicrobial naphthoquinones to improve their pharmaceutical properties has been accepted by several laboratories. In this review we describe the antimicrobial activity of Lawsonia inermis Linn as a natural resource of naphthoquinones. Work in our laboratory in this area will also be elucidated.