Phytochemical profiling and quantification of bioactive constituents in lyophilized khat (Catha edulis Forsk) leaf extract from central Uganda

Background Phenols, flavonoids, alkaloids, tannins, glycosides and volatile oils are only a few bioactive phytochemicals found in most plants including Catha edulis Forsk which is consumed daily in most regions of Uganda. Objective This study aimed to analyze and quantify the bioactive constituents in lyophilized leaf extract of Catha edulis (‘ Kasenge ’ variety) from central Uganda. Methods Total alkaloids, flavonoids, phenolic and saponins contents were determined using spectrophotometric techniques. The bioactive compounds in the Catha edulis leaves were putatively identified using high-performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC-MS). Result The total alkaloids, phenolics, flavonoids and saponins contents were 0.0063 mg/g atropine equivalent, 0.099 mg/g gallic acid equivalent, 0.047 mg/g quercetin equivalent and saponins 0.69 mg/g diosgenin equivalent. Thirty-four characteristic phytochemical peaks were detected by HPLC and twenty-one possible phytochemical compounds were identified by GC-MS analysis, with 35.01% being 9,12,15-Octadecatrienoic acid, 2,3-dihydroxypropyl ester (Z, Z, Z), and over 21% being hexadecanoic acid, ethyl ester and methyl ester, respectively, followed by phytol (10.38%), butyl 9,12-octadecadienoate (7.58%) and 2,4-Di-tert-butylphenol (3.22%). Conclusions The results of this study will be used as baseline data for future phytochemical and pharmacological studies of the lyophilized variety of Catha edulis from Central Uganda, and will generate a comprehensive phytochemical characterisation of the plant. More analyses with validated analytical techniques and bioactivity assays are needed to confirm compound identities and describe their biological characteristics.