Phytochemicals are chemical compounds often referred to as secondary metabolites. Thirty three
bioactive phytochemical compounds were identified in the methanolic extract of Citrullus colocynthis.
The identification of phytochemical compounds is based on the peak area, retention time molecular
weight and molecular formula. Gas chromatography-mass spectrometry (GC-MS) analysis of C.
colocynthis revealed the existence of the methyl 6-oxoheptanoate, hexanoic acid, 2-isopropyl-2-methyl-
5-oxo-, methyl ester, dodecanoic acid, 3-hydroxy, benzofuran,2,3-dihydro, 1,1-Cyclopropanedimethanol,
2-methyl-?-phenyl, 1,1-cyclopropanedimethanol, 2-methyl-?-phenyl, 12,15-octadecadiynoic acid, methyl
ester, (5?)pregnane-3,20?-diol, 14?,18?-[4-methyl-3-oxo-(1-oxa-4-azabutan, 3-(N,Ndimethyllaurylammonio)
propanesulfonate, 2H-1-benzopyran-3,4-diol,2-(3,4-dimethoxyphenyl)-
3,4dihydro-6-met, 11,13-dihydroxy-tetradec-5-ynoic acid, methyl ester,
Cyclopenta[1,3]cyclopropa[1,2]cycloheptan-3(3aH)-one,1,2,3b,6,7, 4-(2,4,4-trimethyl-cyclohexa-1,5-
dienyl)-but-3-en-2-one, 1-tetradecanamine,N,N-dimethyl, ?-D-glucopyranoside, O-?-D-glucopyranosyl-
(1,fwdarw.3)-?-D-fructo, acetamide, N-methyl-N-[4-(3-hydroxypyrrolidinyl)-2-butynyl]-, 9-
octadecenamide,(z)-, butyrophenone,2´,3,4´,6´-tetramethyl-, ethyl 5,8,11,14,-eicosatetraenoate, 9,12,15-
octadecatrienoic acid, 2,3,-dihydroxypropyl ester, (Z,Z,Z)-, 1H-cyclopropa[3,4]benz[1,2-e]ezulene -
5,7b,9,9a 476.241018tetrol,1a,1b,4,4a, 9,12,15-octadecatrienoic acid, 9,10-Secocholesta -5,7,10(19)-
triene-3,24,25,-triol,(3?,5Z,7E)-, 9,12,15-Octadecatrienoic acid,2,3-dihydroxypropyl ester, (Z,Z,Z)-,
triazido-(1,2,3,4,5-pentamethylcyclopenta-2,4-dienyl)-german, ethyl iso-allocholate, ?-N-Normethadol,
Octadecanoic acid, 2-hydroxy-1-(hydroxymethyl)ethyl ester, phthalic acid , decyl oct-3-yl ester, 1,2-
Benzenedicarboxylic acid , bis(8-methylnonyl)ester, phthalic acid, di(6-ethyl-3-octyl)ester, y-tocopherol,
1,4-ethanonaphthalene -6,9(4H)-dione,1,4a,5,8a-tetrahydro-4,5,7,10 and vitamin E. Methanolic extract of
bioactive compounds of C. colocynthis was assayed for in vitro antibacterial activity against Proteus
mirabilis, Escherichia coli, Pseudomonas aerogenosa, P. mirabilis, Staphylococcus aureus and
Klebsiella pneumonia by using the diffusion method in agar. The zone of inhibition was compared with
different standard antibiotics. The diameters of inhibition zones ranged from 4.91±0.260 to 1.03±0.200
mm for all treatments.