Abstract The present study describes a method for simultaneous analysis of cocaine, benzoylecgonine and cocaethylene in urine samples. After solid phase extraction, Gas Chromatography-Mass Spectrometry was used for identification and quantification. The calibration curves were linear at 20 - 3000 ng/mL, r2 0.9997 for benzoylecgonine, 15 - 2000 ng/mL, r2 0.9985 and r2 0.9993 for cocaine and cocaethylene, respectively. Accuracy values: cocaine: 93,5 - 102,1%; benzoylecgonine: 97,5 - 104,8%; cocaethylene: 90,6 - 101,5%. Precision values: cocaine: C.V 5,4 - 14,6%; benzoylecgonine: C.V 7,8 - 12,3%; cocaethylene: C.V 5,9 - 12,3%. Detection and quantification limit values: cocaine and cocaethylene:10 ng/mL and 15 ng/mL, respectivalty; benzoylecgonine:15 ng/mL and 20 ng/mL, respectivaley. Recovery values: cocaine: 78,0 - 85,8%; benzoylecgonine: 74,0 - 79,8%; cocaethylene: 83,0 - 91,5%. The method described is advantageous compared to others, as it simultaneously detects the major analytes found in urine samples due to cocaine use and has been successfully validated.

The essential oil (EO) of Ocimum gratissimum inhibited Staphylococcus aureus at a concentration of 0.75 mg/ml. The minimal inhibitory concentrations (MICs) for Shigella flexineri, Salmonella enteritidis, Escherichia coli, Klebsiella sp., and Proteus mirabilis were at concentrations ranging from 3 to 12 <FONT FACE="Symbol">m</FONT>g/ml. The endpoint was not reached for Pseudomonas aeruginosa (>=24 mg/ml). The MICs of the reference drugs used in this study were similar to those presented in other reports. The minimum bactericidal concentration of EO was within a twofold dilution of the MIC for this organism. The compound that showed antibacterial activity in the EO of O. gratissimum was identified as eugenol and structural findings were further supported by gas chromatography/mass spectra retention time data. The structure was supported by spectroscopic methods.