In vitro evaluation of the quality of essential drugs on the Tanzanian market

We evaluated the in vitro availability and its stability under simulated tropical conditions of variousformulations of four essential drugs marketed in Tanzania. We obtained 22 formulations (containingparacetamol, acetylsalicylic acid, chloroquine or sulphadoxine/pyrimethamine) from wholesalepharmacies in Dar es Salaam and the Medical Stores Department (Tanzania). The drug content, in vitroavailability (dissolution) and its stability under simulated tropical conditions were determined usingmethods specified in the United States Pharmacopoeia (USP) 24 monograph of the respective drugs. Allformulations passed the pharmacopoeia requirements for the drug content. However, sevenformulations (three acetylsalicylic acid, two sulphadoxine/pyrimethamine and two paracetamol) failedto meet the USP 24 tolerance limits for dissolution. Another five formulations (three paracetamol andtwo chloroquine) failed to meet the dissolution tolerance limits after being subjected to an acceleratedstability test under simulated tropical conditions (75% RH/40 ?C) for 6 months. The study hasdemonstrated the presence on the Tanzanian market of essential drug formulations that met potencyrequirements and yet had unsatisfactory in vitro availability as they were not robust enough to withstandstorage under simulated tropical conditions.

Broccoli isothiocyanates content and in vitro availability according to variety and origin

Broccoli is considered one of the healthiest vegetables own to its high content of beneficial biologically active compounds – the breakdown products of the glucosinolates, the isothiocyanates. The aim of this work was to characterize the production of isothiocyanates (sulforaphane and iberin and related metabolites) from different sources of glucosinolates by means of comparison between different broccoli cultivars and commercial samples, investigating their composition and in vitro bioavailability. Differences in the major intact glucosinolates were observed between the different experimental and commercial samples showing lower concentrations of glucosinolates the latest. The simulation of digestion reduced the concentration of parental phytochemicals (glucosinolates) producing the hydrolysis to biologically active isothiocyanates. The commercial samples showed lower levels of ITCs than experimental broccoli cultivars. Measurement of the glucosinolates ingested by UPLC-QqQ-MS/MS has allowed an exact quantifying of these compounds, particularly isothiocyanates, which will help to futures cancer chemoprevention studies.