Antimicrobial spectrum of Alchornea cordifolia leaf extract.

The 50% aqueous ethanol extract of Alchornea cordifolia (Schum and Thonn) Muell. Arg. leaf was screened for activity against 74 microbial strains representing aerobic, facultative and anaerobic bacteria as well as fungi. The panel of test strains included organisms from culture collections as well as clinical and environmental isolates. A concentration of 5 mg/mL of extract inhibited 36.5% of the isolates and 95.9% were inhibited by a concentration of 20 mg/mL. Only three strains, all filamentous fungi, were not susceptible to 40 mg/mL of the extract, the highest concentration tested. The extract showed the best activity against gram-positive bacteria and yeasts with inhibitory concentrations against these organisms being under 5 mg/mL. The results demonstrate that the A. cordifolia extract has a very broad spectrum of activity and suggests that it may be useful in the treatment of various microbial infections.

High-performance liquid chromatographic method for the determination of drotaverine in human plasma and urine.

A simple and sensitive HPLC method for the determination of drotaverine in human plasma and urine has been developed. Alkalinized plasma or urine was extracted with organic solvent and the basic components in the organic phase were back-extracted into 0.1 M HCl. An aliquot of the aqueous layer was injected onto the column and the eluent was monitored at 254 nm. Separation was performed on a C18-column with 0.02 M sodium dihydrogen phosphate-methanol (30:70, v/v) containing perchlorate ion at pH 3.2 as mobile phase. Drotaverine was well resolved from the plasma constituents and internal standard. An excellent linearity was observed between peak-height ratios and plasma concentrations and the intra- and inter-assay coefficients of variation were always < 10%. The lowest limit of detection (signal-to-noise ratio 3:1) was 6 ng/ml. The method is suitable for therapeutic monitoring and pharmacokinetic studies of drotaverine in humans as well as in animal models.

Quantitative analysis of 1-naphthol in urine of neonates exposed to mothballs: the value in infants with unexplained anaemia.

In Nigeria, severe NNJ is common in babies exposed to mothballs and other icterogenic agents. High-performance liquid chromatographic (HPLC) method was employed for quantitative analysis of 1 and 2-naphtol in the urine of 50 neonates aged one to 19 days. Five of the 25 babies who had a history of exposure to mothballs, and none of the babies without a history of exposure had 1-naphtol in their urine. The value of 1-naphtol ranged between 0.75 and 11.69 micrograms/ml with mean of 5 +/- 5 micrograms/ml. The overall correlation coefficient (r) between bilirubin values and 1-naphtol was 0.1 while it was 1 in the three G-6-PD deficient infants. The procedure will be very useful in the evaluation of infants with unexplained NNJ, anaemia, acute haemolytic jaundice and haemoglobinuria if naphthalene poisoning is suspected.

Smooth muscle relaxing flavonoids from Alchornea cordifolia.

Alchornea cordifolia (Schum. & Thonn.) Muell. Arg. (Euphobiaceae) is widely distributed throughout tropical Africa, where it is used extensively in traditional medicine. Conditions for which the plant has enjoyed wide use are: coughs, gonorrhoea, yaws, ulcer, rheumatic pains, fever and bronchial troubles. This paper reports isolation of smooth muscle relaxing flavonoids from the leaves of the plant.

Phenolic analogues of reversed esters of pethidine.

The preparation and stereochemical characterization of phenolic analogues of the reversed ester of pethidine, alpha- and beta-prodine and a 1-phenethyl congener are described. All the compounds were weakly active or inactive as agonists in rodent antinociceptive tests and failed to antagonize fentanyl in rats. The results substantiate the view that the morphine and 4-phenylpiperidine groups of analgesics differ in their modes of interaction with opiate receptors, except possibly when the piperidine derivative carries a C-4 carbon substituent.