Bioactivity-monitored isolation of antibacterial principles of Treculia africana stem bark

Treculia africana Decne (Moraceae), commonly known as African breadfruit (Yoruba: Afon) is a plant food native to tropical West and parts of East Africa. It is an unbuttressed large tree 24 – 37 m high with a fluted bole up to 3 m in girth. The bark is smooth and exudes abundant latex on slashing. Ethno-medicinally, it is used as a vermifuge, febrifuge galactogogue and laxative (Irvine,1961). The root bark hydro-acetone extract, solvent-partition fractions were evaluated for antibacterial activities using the TLC-bioautographic assay technique and B. subtilis spore suspension as the test organism. Bioactivity-monitored fractionation of the active ethyl-acetate-soluble fraction revealed that only fractions VI and VIII were active out of the nine pooled column chromatographic (Silica gel, hexane: ethylacetate mixtures) fractions. Reversed phase preparative thin layer chromatography of chromatographic fraction VIII resulted in the isolation of licoagrochalcone A and a coumarin derivative identified as bergapten (IR, NMR, MS). The results provide some justifications for the use of T. africana in folkloric medicine for treatment of infectious diseases in the tropics.

Keywords: Treculia africana, Moraceae, licoagrochalcone A, antibacterial activity

References:

[1] Irvine F R (1961) Woody Plants of Ghana, Oxford University Press.