In vitro antioxidant and inhibitory activity of water decoctions of carob tree (Ceratonia siliqua L.) on cholinesterases, α-amylase and α-glucosidase

Abstract

This work reports the in vitro inhibitory activity of water decoctions of leaves, germ flour, pulp, locust bean gum and stem bark of carob tree on α-amylase, α-glucosidase, acetylcholinesterase and butyrylcholinesterase. The antioxidant activity and the chemical characterisation of the extracts made by spectrophotometric assays and by high-performance liquid chromatography are also reported. Leaves and stem bark decoctions strongly inhibited all the enzymes tested, had significant antioxidant activity and the highest total phenolics content. The major compounds were identified as gallic acid in the leaves and gentisic acid in the stem bark.

Keywords::

• anti-hyperglycaemic
• carob tree
• diabetes
• neurological disorders

Acknowledgement

The authors thank DANISCO Portugal Industrias de Alfarroba, LDA for providing the germ flour samples.

Additional information

Funding

This work was partially supported by CICYT [grant number CTQ2006-03794/BQU]; Instituto de Salud Carlos III [grant number CB06-01-0074], [grant number PI060624]; the Generalitat de Catalunya [grant number 2005SGR 00662]; the Institute for Research in Biomedicine, and the Barcelona Science Park. L. Custódio thanks the Portuguese Foundation for Science and Technology (Portugal) for a post-doctoral grant [grant number SFRH/BPD/20736/2004].