Table 1: Antimicrobial activity of different extracts of stem-bark of C. procera tested on Gram-positive and Gram-negative bacteria at 100  𝜇 g/mL concentration and their cytotoxic potential was evaluated against human macrophage (U-937) cell lines by XTT assay at 2000, 1000, 500, 250, 100, 50, 25, and 12.5  𝜇 g/mL doses.

Crude extractsPhytochemical screeningYieldE. coli E. aerogenesP. vulgaris P. mirabilis P. aeruginosa S. aureus Cytotoxicity ( 𝜇 g/mL)

(1) HexaneFlovanoids5.36 gm 1 1 ± 0 . 9 4 7 ± 0 . 1 9 ± 0 . 0 6 8 ± 0 . 1 2 <250
(2) Ethyl acetateSteroids3.42 gm 1 8 ± 0 . 0 6 1 7 ± 0 . 2 7 1 5 ± 0 . 2 2 5 ± 0 . 0 6 <500
(3) DichloromethanePolyphenols4.78 gm 1 2 ± 0 . 4 8 ± 0 . 2 3 1 1 ± 0 . 4 8 1 3 ± 0 . 2 1 <500
(4) MethanolTerpenoids5.98 gm 1 4 ± 0 . 3 1 1 9 ± 0 . 2 2 3 ± 0 . 4 2 0 ± 0 . 6 8 ± 0 . 1 2 2 7 ± 0 . 0 6 >2000
(5) AqueousGlycosides; Tannins; saponins7.15 gm 1 1 ± 0 . 1 4 2 2 ± 0 . 7 2 5 ± 1 . 3 2 0 ± 0 . 1 2 9 ± 0 . 2 3 2 8 ± 0 . 1 5 >2000
(6) ChloramphenicolStandard antibiotic30  𝜇 g 2 1 ± 0 . 3 4 2 4 ± 0 . 3 2 3 ± 0 . 1 2 2 6 ± 0 . 2 3 1 0 ± 0 . 3 5 2 9 ± 0 . 1 2

Clinical isolates of Gram-positive and Gram-negative bacteria were used. Values are mean ± SD of three replicates ( 𝑛 = 3 ), inhibition zones in diameters (mm) produced by the extract around the discs. Size of disc was 6 mm. Absence of bacterial inhibition denoted by (—), that is, no inhibition zone around the disc by crude extract of plants.