Comparative in vitro quality assessment of five brands of furosemide tablets marketed in Port Harcourt, Nigeria

Background: Medication failure, high morbidity and mortality resulting from the circulation and consumption of fake, adulterated and substandard medicines have been a worrisome issue to health practitioners, patients and drug regulatory agencies of Nigeria.Objective: This study aims at evaluating some brands of furosemide tablets that are marketed in Port Harcourt, Nigeria to know if they meet with their label claims and British Pharmacopoeia (BP) or the United States Pharmacopoeia (USP) set limits for such products.Materials and Methods: Five brands of furosemide tablets marketed in Nigeria were randomly collected from different retail pharmacy outlets and investigated for uniformity of tablet weight, disintegration, friability, hardness, and drug release profile using standard methods. Two assay methods based on titrimetry and spectrophotometry were employed for the determination of the content of furosemide in the tablet formulations or its bulk drug.Results: Results obtained showed tablet weight in the range of 174 mg ± 0.05% to 274 mg ± 0.01 %, hardness ranging from 3.20 ± 0.01 to 10.70 ± 1.70 kg/F, friability of < 1 %, disintegration time of 5.20 ± 0.88 to 9.30 ± 0.50 min, drug release of > 80 % within 30 min and assay of 86.45 to 100.80 % .Conclusion: Most of the tablet batches tested met with label claim in terms of the content of furosemide and also complied with acceptance limits of the British Pharmacopoeia (BP) or the United States Pharmacopoeia (USP) and were adjudged to be of good quality.Keywords: Furosemide, active pharmaceutical ingredient, British Pharmacopoeia, United States Pharmacopoeia

The Effects of Surfactant and Storage Conditions on the In-Vitro Release of Quinine Suppository Made from Witepsol Base

Background: The need to develop quinine suppository formulation as an alternative to the intravenous parenteral dosage form in severe cases of malaria necessitates this study. The aim is to demonstrate the effect of surfactant, polysorbate (Tween® 20), and storage conditions on the in-vitro release rate of quinine suppositories made from Witepsol H15 base.Methods: Different batches of quinine bisulphate suppositories were made from Witepsol HI5 base by fusion method incorporating Tween® 20, as a surfactant at 0, 0.5, 1.0, 2.0 and 4.0 % w/w concentrations. Some of these suppositories were stored at room temperature (30 ± 2 ˚C) while the rest were stored in the refrigerator (10 + 2˚C) for a period of 21 days and were then analyzed. The physicochemical properties of the suppositories were determined by several tests which include content uniformity, melting range test, hardness and in- vitro drug release rate.Results: The melting ranged from 20 – 30 min for suppositories without surfactant while those with the surfactant were from 3 – 12 min. Suppositories with surfactant had the same trend in hardness. For preparation containing 4% w/w of surfactant, (3800 - 4000 g pressure at room temperature and 3800 – 2600 g pressure in a refrigerator), respectively for days 1 and 12. The active constituent for 0, 0.5, 1.0, 2.0 and 4.0% w/w concentrations of incorporated Tween 20℗ were 98.00, 82.30, 77.60, 81.90 and 76.73 % respectively while the in-vitro release on day 1 after 60 min were 78.32 ± 0.34, 75.69 ± 0.66, 84.34 ± 0.35, 90.50 ± 0.10 and 98.10 ± 0.30 %.Conclusion: This study on day 1 reveals an enhanced effect of the surfactant on the in-vitro release of quinine bisulphate from the suppositories with the highest effect being at the concentration of 4.0 % w/w of Tween 20. Storage of the suppositories at room temperature and refrigeration had a surprising effect of increasing hardness and softening the suppositories, respectively with time.Keywords: Antimalarial; Quinine; Suppositories; Surfactant; Witepso

Chemical constituents from the stem bark of Pentaclethra macrophylla Benth (Fabaceae)

Background: Plants have served as source of lead discovery in drug development; there is the need to look into our ethnomedicinal plants for the purpose of identifying bioactive antibacterial agents to combat the growing antibacterial resistance to current drugs.Objective: The present study investigated the antibacterial activity of the extract and soluble fractions of Pentaclethra macrophylla against some selected pathogens and isolation of active constituents using chromatography and spectroscopic techniques.Materials and methods: The pulverized stem bark of P. macrophylla was extracted to exhaustion with 70% methanol and the combined crude methanol extract after removal of solvent was partitioned with ethyl acetate and n-butanol to give ethyl acetate and n-butanol soluble fractions. Antibacterial activity was evaluated on the crude methanol extract,ethylacetate and n-butanol fractions against five pathogenic bacteria using agar diffusion assay method. The active ethylacetate and n-butanol fractions were subjected to Column chromatography and subsequent purification over sephadex LH-20 afforded compounds I, II and III. The structures of these compounds were elucidated using NMR and MS and are reported in this plant for the first time.Results: Antibacterial activity showed that the extract and fractions at 10mg/mL showed activity against B. subtilis with zones of inhibition of 8.0 ± 2.89, 16.0 ±1.73 and 9.5 ± 1.78 respectively for 70% methanol extract, ethyl acetate, and n-butanol fractions. Ethyl acetate soluble fraction at (10mg/mL) had a good activity against B. subtilis and S. aureus with inhibition zones of 16.0 and13.5mm compared with Levofloxacin (1.5μg/mL) having zones diameter of 21.1 and 16.6mm, however, none of the extract or fractions showed activity against K. pneumonae. Compound I was identified as methyl gallate, compound II: Bergenin and compound III: 11-O-galloylbergenin. The structures of these compounds were elucidated using NMR and ESI-MS and compared with literature.Conclusion: Finding from this work showed that the ethylacetate fraction is the most active and compounds I, II were isolated from the fraction, while the n-butanol furnished compound III. These compounds are being reported for the first time in this plant and have been known to possess antibacterial activity, thereby given credence to the ethnomedicinal use of this plant against infections.Keywords: Pentaclethra macrophylla, Antibacterial, Methyl gallate, Bergenin, 11-O-galloylbergeni