Bioequivalence studies of cetirizine tablets using the urine excretion data of healthy Ghanaian male volunteers.

Background: In the wake of economic challenges, the role of generic medicines has become crucial in meeting the healthcare needs of people. Their use, however, can only be guaranteed if established to be bioequivalent to their corresponding innovator products. Aim: In this study, we assess the suitability of a generic brand of cetirizine hydrochloride tablet to be used in place of the innovator brand on the Ghanaian market through bioequivalence assessment. Method: An HPLC bioanalytical method was developed and validated for the detection and quantitation of cetirizine in a urine matrix. This was then used to quantify the amount of cetirizine excreted unchanged in urine samples of 12 healthy male volunteers collected over a 24-h period using a two-way crossover design approach. Results: Chromatographic separation was successfully achieved with an isocratic elution on a reverse-phase column. The mean retention time for cetirizine was 2.890 ± 0.243 min. The mean cumulative amounts of cetirizine in the reference and test drugs excreted were 5.69 ± 0.98 mg and 5.82 ± 1.96 mg respectively. Other pharmacokinetic parameters including mean relative Areas Under Curve (AUC0-24) of 13.32 and 13.05 µg/mL, and peak Concentration (Cmax) of 3.378 and 3.043 µg/mL at the times at which Cmax was observed (Tmax) being 7.25 and 7.42 min were established respectively for the reference and test drugs. The relative bioavailability was determined to be 102.28, making the locally manufactured brand bioequivalent to the innovator brand. Conclusion: The locally manufactured test Cetirizine drug was found to be bioequivalent with the innovator brand and could serve as a suitable alternative to the latter. Additionally, relevant pharmacokinetic parameters for cetirizine has been established using urinary excretion data.

Exposure of consumers to substandard antibiotics from selected authorised and unauthorised medicine sales outlets in Ghana.

OBJECTIVE: To assess the quality of antibiotics sampled from authorised sales outlets (ATs) (i.e. hospitals/health centres, pharmacies and licensed chemical shops) and unauthorised sales outlets (UATs) (mainly street vendors) in Ghana and to explore the health-seeking behaviour of medicine consumers. METHODS: The contents of 14 active pharmaceutical ingredients (APIs) in 348 sampled products were determined using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Data on health-seeking practices were collected through entry and exit interviews and field observations from ATs and UATs. RESULTS: It was observed that 66.38% of all sampled antibiotic products were substandard; they either contained less (<90%) or more API (>110%) than the label claim. Medicines from UATs recorded substantially less API contents than those from ATs (F(2,419)  = 43.01, P < 0.0001). For example, 90.54% of street vendor samples contained < 90% of the APIs. 75.93% of consumers often sought self-treatment with drugs without a prescription from UATs, as they perceived UATs as easily accessible, trustworthy and knowledgeable, and their medicines as inexpensive. These consumers rather thought of the formal healthcare providers as alternative sources. CONCLUSIONS: Consumers who purchase from UATs are at high risk of receiving substandard medicines. The quality of medicines in the national healthcare system, in the supply chain and in the distribution system needs to be monitored regularly to reduce the incidence of substandard medicines and their impact on antimicrobial resistance. The fight against substandard medicines needs to incorporate a full understanding of socioeconomic factors that drive consumer decisions regarding their health and choice of healthcare providers.

OBJECTIF: Evaluer la qualité des antibiotiques prélevés auprès des vendeurs autorisés (VA) (c'est-à-dire les hôpitaux/centres de santé, les pharmacies et les magasins de produits chimiques agréés) et des vendeurs non autorisés (VNA) (principalement les vendeurs de rue) au Ghana et étudier le comportement des utilisateurs de médicaments en quête de santé. MÉTHODES: Le contenu de 14 principes actifs (PA) pharmaceutiques dans 348 produits échantillonnés a été déterminé à l'aide d'une méthode validée de chromatographie liquide et de spectrométrie de masse en tandem (LC-MS/MS). Les données sur les pratiques de recherche de santé ont été collectées par le biais d'entretiens d'entrée et de sortie, et d'observations sur le terrain des VA et des VNA. RÉSULTATS: Il a été observé que 66,38% de tous les produits antibiotiques échantillonnés étaient inférieurs aux normes; ils contenaient soit moins (<90%), soit plus de PA (>110%) que ce qui était indiqué sur la notice. Les médicaments provenant des VNA ont enregistré une quantité de PA sensiblement inférieure à celle des VA (F(2,419)  = 43.01, P < 0,0001). Par exemple, 90,54% des échantillons de vendeurs de rue contenaient <90% de PA. 75,93% des utilisateurs ont souvent cherché à se soigner eux-mêmes avec des médicaments sans ordonnance des VNA, car ils ont perçu les VNA comme étant facilement accessibles, fiables et bien informés, et leurs médicaments comme étant peu coûteux. Ces utilisateurs considéraient également les prestataires de soins de santé officiels comme des sources alternatives. CONCLUSIONS: Les utilisateurs qui s'approvisionnent auprès des VNA courent un risque élevé de recevoir des médicaments de qualité inférieure. La qualité des médicaments dans le système national de santé, dans la chaîne d'approvisionnement et dans le système de distribution doit être contrôlée régulièrement pour réduire l'incidence des médicaments de qualité inférieure et leur impact sur la résistance aux antimicrobiens. La lutte contre les médicaments de qualité inférieure doit intégrer une compréhension complète des facteurs socioéconomiques qui déterminent les décisions des utilisateurs concernant leur santé et le choix des prestataires de soins de santé.

MALDI-HRMS imaging and HPLC-HRESI-MSn characterisation of kaurane diterpenes in the fruits of Xylopia aethiopica (Dunal) A. Rich (Annonaceae).

INTRODUCTION: Kaurane diterpenes, notably xylopic acid, have demonstrated important biological activities including analgesia, anti-oxidant, antimicrobial and cytotoxicity. The fruits of Xylopia aethiopica have been reported to be a rich source of kaurane diterpenes. OBJECTIVE: An analytical approach for detailed imaging and characterisation of selected kaurane diterpenes was developed using matrix-assisted laser desorption/ionisation high-resolution mass spectrometry (MALDI-HRMS) imaging techniques and high-performance liquid chromatography-high resolution electrospray ionisation-tandem mass spectrometry (HPLC-HRESI-MSn ) studies, respectively. METHODS: The images of the compounds were constructed based on selected ions from their HRESI-MS spectra. The matrix employed comprised a solution of α-cyano-4-hydroxycinnamic acid (HCCA) in acetonitrile-water with trifluoroacetic acid (TFA). HPLC-HRESI-MSn measurements were conducted on an LTQ-Orbitrap spectrometer equipped with a heated electrospray ionisation (HESI)-II source. RESULTS: The analytical strategy adopted showed the spatial distribution of the compounds in the fruits of X. aethiopica based on the dominant ions at m/z 301.2163 [M + H - HOCOCH3 ]+ and m/z 399.1932 [M + K]+ for xylopic acid, m/z 317.2111 [M + H]+ and m/z 355.1670 [M + K]+ for 15-oxo-ent-kaur-16-en-19-oic acid and m/z 303.2319 [M + H]+ for ent-kaur-16-en-19-oic acid. The fragmentation patterns of the compounds were proposed based on the HRESI-MSn measurements. CONCLUSIONS: The study revealed the spatial variability, differential behaviours and specificity of the selected kaurane diterpenes in the fruit, seed and pericarp. The compounds under study were predominantly restricted to the pericarp of the fruit with trace amounts in the seed.

Resistance Modulation Action, Time-Kill Kinetics Assay, and Inhibition of Biofilm Formation Effects of Plumbagin from Plumbago zeylanica Linn.

Antimicrobial resistance (AMR) is a threat to the prevention and treatment of the increasing range of infectious diseases. There is therefore the need for renewed efforts into antimicrobial discovery and development to combat the menace. The antimicrobial activity of plumbagin isolated from roots of Plumbago zeylanica against selected organisms was evaluated for resistance modulation antimicrobial assay, time-kill kinetics assay, and inhibition of biofilm formation. The minimum inhibitory concentrations (MICs) of plumbagin and standard drugs were determined via the broth microdilution method to be 0.5 to 8 µg/mL and 0.25-128 µg/mL, respectively. In the resistance modulation study, MICs of the standard drugs were redetermined in the presence of subinhibitory concentration of plumbagin (4 µg/mL), and plumbagin was found to either potentiate or reduce the activities of these standard drugs with the highest potentiation recorded up to 12-folds for ketoconazole against Candida albicans. Plumbagin was found to be bacteriostatic and fungistatic from the time-kill kinetics study. Plumbagin demonstrated strong inhibition of biofilm formation activity at concentrations of 128, 64, and 32 µg/mL against the test microorganisms compared with ciprofloxacin. Plumbagin has been proved through this study to be a suitable lead compound in antimicrobial resistance drug development.

Investigation of Acid-Base Indicator Property of Plumbagin from Plumbago zeylanica Linn.

There has been an increasing interest in the search for colour indicators of natural origin for titrimetric analysis. This is due to some challenges associated with the currently used synthetic ones. This study evaluates and validates the acid-base indicator property of plumbagin isolated from Plumbago zeylanica Linn. Plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) was isolated from the roots of Plumbago zeylanica Linn using silica gel chromatography and characterized using spectroscopic methods in comparison with those reported in the literature. Its acid-base indicator property was evaluated alongside phenolphthalein and methyl orange, after it was found to exhibit a sharp change in colour at various pH ranges. The plumbagin indicator was successfully used to assay ibuprofen powder and tablets (400 mg) using the British Pharmacopoeia (2013) method. Data obtained were analyzed statistically by Student's t-test and one-way ANOVA in GraphPad Prism (version 5.01, 2010). Analysis of the use of the plumbagin indicator in acid-base titrations between strong acids and strong bases and between weak acids and strong bases has been evaluated and validated according to the ICH guidelines. Plumbagin use in ibuprofen powder and tablets has also been verified. Plumbagin has been validated for use as an indicator suitable for different acid-base titrations and the analysis of ibuprofen.

Antibacterial secondary metabolites from an endophytic fungus, Fusarium solani JK10.

Extensive chemical investigation of the endophytic fungus, Fusarium solani JK10, harbored in the root of the Ghanaian medicinal plant Chlorophora regia, using the OSMAC (One Strain Many Compounds) approach resulted in the isolation of seven new 7-desmethyl fusarin C derivatives (1-7), together with five known compounds (8-12). The structures of the new compounds were elucidated by analysis of their spectroscopic data including 1D, 2D NMR, HRESI-MSn and IR data. The relative configuration of compounds 1/2 was deduced by comparison of their experimental electronic circular dichroism (ECD) and optical rotation data with those reported in literature. The absolute configuration of solaniol (10), a known compound with undefined absolute stereochemistry, was established for the first time by X-ray diffraction analysis of a single-crystal structure using Cu-Kα radiation. The antibacterial activities of the crude fungal extract and the compounds isolated from the fungus were evaluated against some clinically important bacterial strains such as Staphylococcus aureus and Bacillus subtilis, as well as an environmental strain of Escherichia coli and the soil bacterium Acinetobacter sp. BD4. Compounds 3/4 and 6 exhibited antibacterial efficacies against the soil bacterium Acinetobacter sp., comparable to the reference standard streptomycin. All the tested compounds (1-9) demonstrated antibacterial activity against the environmental strain of E. coli, whereas no antibacterial activity was observed against S. aureus and B. subtilis. The antibacterial activity of the isolated compounds typically against E. coli and Acinetobacter sp. provides further insight into the possible involvement of root-borne endophytes in chemical defense of their host plants in selected ecological niches.

Effects of an ethanol extract and the diterpene, xylopic acid, of Xylopia aethiopica fruits in murine models of musculoskeletal pain.

CONTEXT: Fruits of Xylopia aethiopica (Dunal) A. Rich. (Annonaceae) are used traditionally to manage arthritis, headache and other pain disorders. OBJECTIVE: The analgesic properties of the X. aethiopica ethanol fruit extract (XAE) and xylopic acid (XA) were evaluated in musculoskeletal pain models. MATERIALS AND METHODS: Acute muscle pain was induced in gastrocnemius muscle of Sprague-Dawley rats with 3% carrageenan (i.m.). Rats received XAE (30-300 mg/kg), XA (10-100 mg/kg) or morphine (1-10 mg/kg) after 12 h. Effects of XAE and XA on muscle pain were assessed by measuring post-treatment grip strength of the rats. Chronic muscle pain was similarly induced, but drug treatment was on the eighth day and effects of XAE and XA assessed with Randall-Selitto test for hyperlagesia. Acute-skeletal pain was induced in knee joints of rats with 3% carrageenan-kaolin mixture and effects determined 12-h later. Similar induction protocol was used for chronic knee pain with treatment and measurement as done for chronic muscle pain. RESULTS: XAE and XA significantly and dose-dependently ameliorated both acute muscle (ED50 mg/kg: XAE = 22.9; XA = 6.2) and skeletal hyperalgesia (XAE = 39.9; XA = 17.7) induced by 3% carrageenan. Similarly, chronic skeletal hyperalgesia was reduced by XAE and XA treatment similar to morphine (ED50: XAE = 13.0; XA = 4.6). This reduction was also seen in chronic muscle hyperalgesia (ED50: XAE = 79.1; XA = 42.7). XAE and XA significantly reduced the spread of hyperalgesia to contralateral limbs in both models of chronic hyperalgesia. CONCLUSION: These findings establish analgesic properties of the ethanol fruit extract of X. aethiopica and xylopic acid in musculoskeletal pain.

Prenylated 2-arylbenzofuran derivatives with potent antioxidant properties from Chlorophora regia (Moraceae).

Extracts of Chlorophora regia are frequently used in Ghana in traditional medicine. There is, however, no reported data on the chemical composition of the plant. Comprehensive phytochemical investigation of the stem bark of C. regia resulted in the isolation of three new prenylated 2-arylbenzofuran derivatives, regiafuran A-C (1-3), and one new prenylated flavonol (4), together with fifteen known compounds (5-19). Their structures were elucidated by combined spectroscopic analysis of their NMR and HRESI-MS(n) data. Compounds 1, 2, 5, 9 and 15 exhibited remarkable free radical scavenging properties with IC50 values of 1.9 µg/ml, 2.4 µg/ml, 2.2 µg/ml, 2.1 µg/ml and 1.8 µg/ml, respectively, compared to the standard trolox (IC50 1.1 µg/ml). The isolated compounds did not, however, show any anti-inflammatory potential when tested using a PGE2 (prostaglandin E2) competitive enzyme immunoassay.

Anti-allodynic and Anti-hyperalgesic effects of an ethanolic extract and xylopic acid from the fruits of Xylopia aethiopica in murine models of neuropathic pain.

BACKGROUND: Fruit extracts of Xylopia aethiopica are used traditionally in the management of pain disorders including headache and neuralgia. An animal model of vincristine-induced sensory neuropathy was developed after repeated intraperitoneal injection in rats and used in the present work to study the effects of the ethanolic extract of X. aethiopica (XAE) and its diterpene xylopic acid (XA) in vincristine-induced neuropathic pain. MATERIALS AND METHODS: Vincristine (0.1 mg kg(-1) day(-1)) was administered during two cycles of five consecutive days to induce chemotherapy-induced neuropathic pain. Static tactile anti-allodynic, anti-hyperalgesic, and cold anti-allodynic effects of XAE (30-300 mg kg(-1)) and XA (10-100 mg kg(-1)) were assessed using Von Frey filaments of bending forces of 4, 8, and 15 g, the Randall-Selitto paw pressure test, and cold water (4.5°C), respectively. RESULTS: Administration of vincristine caused the development of allodynia and hyperalgesia with no significant motor deficit, spontaneous pain, and foot deformity. XAE (30-300 mg kg(-1)) and XA (10-100 mg kg(-1)) exhibited anti-hyperalgesic, tactile, and cold anti-allodynic properties with XA exhibiting greater potency than XAE. Pregabalin (10-100 mg kg(-1)) used as control produced similar effect. CONCLUSION: These findings establish the anti-allodynic and anti-hyperalgesic effects of the ethanolic fruit XAE and its major diterpene XA in vincristine-induced neuropathtic pain.

An HPLC method for the direct assay of the serotonin precursor, 5-hydroxytrophan, in seeds of Griffonia simplicifolia.

5-Hydroxytryptophan (1) is a naturally occurring amino acid found in significant levels in seeds of Griffonia simplicifolia and used in the treatment of the numerous effects of serotonin deficiency syndrome. An HPLC method has been developed for the direct assay of 1 in seeds of G. simplicifolia which overcomes the problems associated with previous techniques. By optimising the solvent extraction procedures and the HPLC conditions, levels of 1 could be estimated following a single-step seed extraction. The chromatographic conditions, solvent system and the extraction technique developed make this method relatively simple, fast and efficient. Using the described methods, the highest ever levels of 1 (namely, 20.83% on a fresh weight basis) have been determined in seeds of G. simplicifolia obtained in Ghana.