CHAPTER 1

INTRODUCTION

The genus Indigofera Linn. is a large genus of about 700 species of flowering plants belonging to the sub-family Papilionoideae in the family Fabaceae / Leguminosae. They occur throughout the tropical and subtropical regions of the world. Burkill (1995) recognized 60 species while Soladoye and Lewis (2003) recorded 60 species in Nigeria with over 60% abundance in the Northern region of the country with 27 species distributed across the South Western area of the country. Indigofera in Greek means indigo dye which is famous for the natural blue colors obtained from the leaflets and branches of this herb. The most important of the species are Indigoferaarrecta and Indigofera tinctoria.

Indigofera spp. display excellent adaptation to a range of environments, and possess diverse morphological and agronomic attributes, significant to their use as forage and cover crops (Hassen et al., 2006). Some of these species, Indigofera tinctoria and Indigofera suffruticosa are used to produced indigo dyes while some have medicinal values such as Indigofera articulate used for the treatment of toothache,

Indigofera oblongifolia, Indigofera suffruticosa and Indigofera aspalthoides are used as anti–inflammatories for treatment of insect stings, snake bites and swellings (Shahjahan et al., 2005); and Indigofera arrecta extract is used to relieve ulcer pain.

The stem of Indigofera tinctoria is chewed to cure cough and decoction of leaves is used to cure chest pains, epilepsy, nervous disorders, asthma, bronchitis, fever and complaints of stomach, liver, kidney and spleen- especially in Cameroon (Takawira-Nyenya and Cardon, 2005). The twine paste cures dislocation. Also the warm leaves dismiss bruises (Ibe and Nwufo, 2005). Phytochemical investigation of Indigofera species shows that they are rich in organic and fatty acids, flavonoids such as carotenoids and coumarins (Yinusa et al., 2007).