Phytochemicals, Tannins Characterization and Antimicrobial Analyses of Dried Carrot Greens Extracts

In spite of the richness in nutritive values, minerals and vitamins content of chlorophyll which is highly contained in carrot greens, these greens are usually cut and thrown away as waste, these underutilizations of the carrot greens instigated the investigation for biological compounds of medicinal importance. This research is focus on the investigation of tannins in carrots greens and its biological activity, via extraction in 70 % acetone and partitioning in diethyl ether and distilled water. The extract was subjected to phytochemical screening, thin layer chromatography (TLC), column chromatography (CC) and antimicrobial activity test. The isolation of the tannins was carried out by preparative thin layer chromatography (PrepTLC). The isolated tannin was further analysed by TLC using ethylacetate-ethanol-water (8:2:1.5) as solvent system along with standard tannins, high performance liquid chromatography (HPLC) and fourier tranform infra-red spectroscopy. The plant extract gave a percentage extract of 5.45, 2.24 of aqueous and 3.22 of diethyl ether fractions after partitioning. The phytochemical screening of the crude gave tannins, alkaloids, flavonoids, saponins, cardiac glycosides and phenols. The TLC result of the isolated tannin revealed three (3) different tannins out of which two (2) matched with standard gallic acid and catechol according to similarity in Rf values (0.47 and 0.76 respectively). The HPLC analysis of the tannin also confirmed the appearance of three different tannins peaks eluting at retention times 2.199, 2.967 and 4.944 mins. The FT-IR supports the presence of the suspected compounds by showing broad absorptions peaks at 3348cm-1 for OH stretch, a medium peak at 1643cm-1 resulting from C=C aromatic stretch, and C-O absorption at 1211cm-1. Both crude and aqueous fraction of the extract show positive activity on some gram-positive organism. The activity on Streptococcus pneumoniae of the tannin fraction is concentration dependant and these indicated that it can be used as remedy in respiratory tract infections such as those caused or aggrevated by S. pneumoniae. The appreciable quantity of flavonoids and tannins indicates they can be responsible for healings of wounds, inflamed mucous membranes, venous ulcers and exhibit radical scavenging activities.