Antimicrobial activity of some Alnus species.

OBJECTIVE: The increasing prevalence of resistant microorganisms forced scientists to find new antimicrobial substances from different sources like medicinal plants. The aim of this study was to determine the antimicrobial activities of leaf extracts of some Alnus sp. against some bacteria and a yeast. MATERIALS AND METHODS: Aqueous and ethanolic leaf extracts of A. glutinosa subsp. glutinosa, A. orientalis var. orientalis, A. orientalis var. pubescens were screened for their antimicrobial activities against Staphylococcus aureus ATCC 25923, S. aureus ATCC 43300 (MRSA), Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Candida albicans ATCC 10231. Broth dilution method was used to determine the antimicrobial activities of plant extracts. RESULTS: Ethanolic extracts of tested species exhibited better antimicrobial activity than aqueous extracts. Ethanolic extracts of tested species possessed activity having MIC values of 0.125-0.250 mg/ml against the tested microorganisms. No antibacterial activity was observed against B. subtilis, E. coli, P. aeruginosa for all the aqueous extracts. Except these aqueous extracts, the others possessed activity having MIC value of 1.000 mg/ml against the tested microorganisms. CONCLUSIONS: To our knowledge, this is the first investigation on the evaluation of antimicrobial activities on aqueous and ethanolic leaf extracts of these species. This study provides significant information about antimicrobial activities of leaf extracts of A. glutinosa subsp. glutinosa, A. orientalis var. orientalis, A. orientalis var. pubescens. It is conceivable that one of the reason for the usage of Alnus glutinosa, in treatment of wound healing in folk medicine, is because of its antimicrobial activity.

HPLC method for the analysis of harmol, harmalol, harmine and harmaline in the seeds of Peganum harmala L.

A simple and sensitive method for separation and determination of harmol, harmalol, harmine and harmaline has been developed and validated. Harmol, harmalol, harmine and harmaline were separated using a Metasil ODS column by isocratic elution with flow rate 1.5 ml/min. The mobile phase composition was Isopropyl alcohol-Acetonitrile-Water-Formic acid (100:100:300:0.3) (v/v/v/v) and pH adjusted 8.6 with triethylamine. Spectrophotometric detection was carried out at 330 nm. The linear range of detection for harmol, harmalol, harmine and harmaline were between 9.375-250, 30.750-246, 31.250-500 and 31.000-248 microg/ml, respectively. The method described was suitable for the determination of harmol, harmalol, harmine and harmaline in the seeds of Peganum harmala L.

LC determination of atropine sulfate and scopolamine hydrobromide in pharmaceuticals.

An accurate, simple, reproducible and sensitive method for the determination of atropine sulfate and scopolamine hydrobromide has been developed and validated. Atropine sulfate and scopolamine hydrobromide were separated using a microBondapack C(18) column by isocratic elution with flow rate 1.0 ml/min. The mobile phase composition was methanol, water, formic acid (165:35:1; v/v/v) and pH adjusted 8.3 with triethylamine. The samples were detected at 230 nm using photo-diode array detector. The linear range of detection for atropine sulfate (I) and scopolamine hydrobromide (II) were between 10.38 and 1038 microg/ml with a limit of quantification (LOQ) of 10.38, 10.00 and 1034 microg/ml with an LOQ of 10.00 microg/ml respectively. The linearity, range, peak purity, selectivity, system performance parameters, precision, accuracy, robustness and ruggedness for (I) and (II) were also shown acceptable values.

The rapid quantitative analysis of phenprobamate and acetaminophen by RP-LC and compensation technique.

For the analysis of phenprobamate and acetaminophen in combination, the main analytical methods used were spectrophotometric compensation technique and Vierordt's method with high performance liquid chromatography, used as an analytical reference method. The first procedure for the simultaneous quantitative determination phenprobamate and acetaminophen by high performance liquid chromatographic (HPLC) method was proposed. The method was standardized using a LiChrosorb RP18-5 column, methanol-water-formic acid (120:80:1 v/v), apparent pH 4.25 with triethylamine, as mobil phase and UV detection at 254 nm. The peak area response versus concentration was linear in a concentration range from 4 to 28 microg ml(-1) of phenprobamate and from 4 to 30 microg ml(-1) for acetaminophen. The correlation coefficients were 0.9999 for phenprobamate and 0.9987 for acetaminophen. The second procedure, based on the compensation technique, is presented for the derivative spectrophotometric determination of binary mixtures with overlapping spectra. The proposed methods, which give thoroughly comparable data, are simple and rapid and allow precise and accurate results.

LC method for the analysis of acetylsalicylic acid, caffeine and codeine phosphate in pharmaceutical preparations.

An accurate, simple, reproducible and sensitive method for the determination of acetylsalicylic acid, caffeine and codeine phosphate has been developed and validated. Acetylsalicylic acid, caffeine and codeine phosphate were separated using a microBondapack C(8) column by isocratic elution with flow rate 1.0 ml/min. The mobile phase composition was 125/125/250/0.5 (v/v) isopropyl alcohol, acetonitrile, water and o-phosphoric acid. The samples were detected at 215 nm using photo-diode array detector. The linear range of detection for acetylsalicylic acid, caffeine and codeine phosphate were between 0.40 and 1000, 0.25 and 250, and 0.48 and 96 microg/ml, respectively. The linearity, range, selectivity, system performance parameters, precision, accuracy, and ruggedness for acetylsalicylic acid, caffeine and codeine phosphate were also shown to have acceptable values.

Spectrophotometric resolution of metronidazole and miconazole nitrate in ovules using ratio spectra derivative spectrophotometry and RP-LC.

Metronidazole and miconazole nitrate in ovules was determined by ratio spectra derivative spectrophotometry and by high-performance liquid chromatography (HPLC). The first method depends on ratio spectra first derivative spectrophotometry, by utilizing the linear relationship between substances concentration and ratio spectra first derivative peak amplitude. The ratio first derivative amplitudes at 242.6 [(1)DD(242.6)], 274.2 [(1)DD(274.2))] 261.8 [(1)DD(261.8))] 273.5 [(1)DD(273.5))]and 281.5 [(1)DD(281.5)] nm were selected for the assay of metronidazole and miconazole nitrate, respectively. The second method is based on high-performance liquid chromatography on a reversed-phase column using a mobile phase of methanol-water-phosphoric acid (30:70:0.20 v/v) (pH 2.8) with programmable detection at 220.0 nm. The minimum concentration detectable by HPLC was 0.9 microg ml(-1) for metronidazole and 0.3 microg ml(-1) for miconazole nitrate and by ratio derivative spectrophotometry 4.0 microg ml(-1) for metronidazole and 0.5 microg ml(-1) for miconazole nitrate. The proposed procedures were successfully applied to the simultaneous determination of metronidazole and miconazole nitrate in ovules with a high percentage of recovery, good accuracy and precision.