Developing a water emulsion bioacaricide from Lippia sp. essential oil for smallholder farmers in Kenya

About the project

UK-registered Partner: University of Lincoln – Dr Bukola Onarinde
Africa-registered Partner: Keola Products Ltd – Brian Langat

The aim of the project was to develop a bioacaricide from a locally available plant, Lippia citriodora, to help tackle anasplasmosis in rural dairy farming in Kenya. L. citriodora is often called lemon verbena, because of the lemon-like aroma emitted from its leaves. This plant was indigenous to South America but introduced into Africa and has many ethnomedicinal uses, but more importantly the antimicrobial, fumigant, contact toxicity and repellent effects of its essential oil have been evaluated.

In this study we successfully extracted and determined the chemical composition using GCMS of essential oils from the leaves of L. citriodora and two indigenous Lippia species, L. javanica and L. kituensis, and Tagetes minuta to be used as positive control. From the resulting L. citriodora essential oil, an emulsifiable concentrate was prepared. This product, that incorporated a bioacide and antifreeze as envisaged, was tentatively named KEOLATIX with ca.20% limonene, hence KEOLATIX 20EC, and was used for efficacy studies.

In vitro studies against blueticks, bruchid beetles and its antibacterial effects against Enterococcus faecium in broth culture was assessed. The product was effective in killing blue ticks and bruchid beetles and inhibiting growth and survival of E. faecium. Therefore, in this study, we successful developed a L. citriodora essential oil-based in emulsifiable concentrate, which has the potential to combat blue ticks, with additional benefits for surface cleaning due to its 99.99% kill rate of E. faecium.

Learn more about the project in this recording from our recent GCRF AgriFood Africa Project Showcase event.