Detection of glucosamine as a marker for Aspergillus niger: a potential screening method for fungal infections.

Several species of fungus from the genus Aspergillus are implicated in pulmonary infections in immunocompromised patients. Broad screening methods for fungal infections are desirable, as cultures require a considerable amount of time to provide results. Herein, we developed degradation and detection methods to produce and detect D-glucosamine (GlcN) from Aspergillus niger, a species of filamentous fungus. Ultimately, these techniques hold the potential to contribute to the diagnosis of pulmonary fungal infections in immunocompromised patients. In the following studies, we produced GlcN from fungal-derived chitin to serve as a marker for Aspergillus niger. To accomplish this, A. niger cells were lysed and subjected to a hydrochloric acid degradation protocol. Products were isolated, reconstituted in aqueous solutions, and analyzed using hydrophilic interaction liquid chromatography (HILIC) in tandem with electrospray ionization time-of-flight mass spectrometry. Our results indicated that GlcN was produced from A. niger. To validate these results, products obtained via fungal degradation were compared to products obtained from the degradation of two chitin polymers. The observed retention times and mass spectral extractions provided a two-step validation confirming that GlcN was produced from fungal-derived chitin. Our studies qualitatively illustrate that GlcN can be produced from A. niger; applying these methods to a more diverse range of fungi offers the potential to render a broad screening method for fungal detection pertinent to diagnosis of fungal infections.

The impact of implementation of the Canadian regulatory requirements on the quality of natural health products: the glucosamine case.

PURPOSE: We investigated whether the recent implementation of the regulatory requirements for the entry to the Canadian market of natural products has resulted in improved quality of the available glucosamine products. METHODS: Eleven available products, of which 8 had been tested in 2002 (7 had contained substantially lower than the label claim of the active ingredient), and a European pharmaceutical grade tablet were assayed for their glucosamine content. The potassium and sodium contents of the products were also tested. RESULTS: Nine of the 11 Canadian products and the European tablet had more than 91% of the label claim of the active ingredient, hence, met the criterion. Two products contained 71 and 78% label claim. The electrolyte contents were very variable but constituted only a small fraction of the daily requirements. CONCLUSION: Most tested glucosamine products passed the Health Canada requirements. This improvement is likely due to the publicity regarding the low quality of the products in the past and also a result, at least in part, of the introduction of the new regulatory requirements. The sub-standard quality of a few tested products is still of concern.

The use of glucosamine, devil's claw (Harpagophytum procumbens), and acupuncture as complementary and alternative treatments for osteoarthritis.

Osteoarthritis is one of the most common chronic inflammatory conditions seen in the general population. Current pharmacological treatments focus on reduction of pain and increased mobility to improve overall quality of life. However, the relief afforded by current standard care is often insufficient and can be associated with significant side effects. Many patients, therefore, seek the option of non-standard therapies, such as nutritional and herbal supplements, acupuncture, and exercise regimens. Glucosamine, Harpagophytum procumbens, and acupuncture are among the most commonly used complementary and alternative medicine approaches utilized by patients suffering from osteoarthritis. Their clinical relevance, safety, and potential mechanisms of action are discussed in this review.

A new expert systems (SeDeM diagram) for control batch powder formulation and preformulation drug products.

The new SeDeM Method is proposed for testing the batch-to-batch reproducibility of the same active pharmaceutical ingredient (API) in powder form. The procedure describes the study of the galenic properties of substances in powder form in terms of the applicability of direct compression technology. Through experimental determination of the SeDeM Method parameters, and their subsequent mathematical treatment and graphical expression (SeDeM Diagram), three batches of the same API were analysed to determine whether it was suitable for direct compression. Batch-to-batch reproducibility of the results was verified. It was concluded that the SeDeM Method is suitable for testing batch-to-batch reproducibility of characteristics in powdered APIs substances. The results obtained confirm that the SeDeM Method is a useful, effective tool for drug-preformulation studies providing the pharmacotechnical data required when formulating a drug in tablet form. In addition, the results were effective for defining the most appropriate manufacturing technology.

Chondroitin product selection for the glucosamine/chondroitin arthritis intervention trial.

OBJECTIVE: To select a high-quality chondroitin dosage form and/or an appropriate source of sodium chondroitin for the National Institutes of Health's Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT). DESIGN: Controlled experimental trials. SETTING: Laboratory. PATIENTS OR PARTICIPANTS: Not applicable. INTERVENTIONS: Commercially available chondroitin products were reviewed, and purified sodium chondroitin from two suppliers was evaluated through tests (infrared and near-infrared identification, moisture content, pH, optical rotation, color and clarity of aqueous solutions prepared from the powders, protein contamination, total residue following ignition and nitrogen content, determination of sodium chondroitin molecular weight, disaccharide analysis, and measurement of chondroitin, sodium, and total glycosaminoglycan content) and an onsite supplier audit. MAIN OUTCOME MEASURES: Purity, potency, and quality of sodium chondroitin powders. RESULTS: No commercially available chondroitin product was deemed appropriate for use in GAIT. Samples of sodium chondroitin powder from two suppliers exhibited similar disaccharide and glycosaminoglycan content. Each contained approximately 2% hyaluronic acid and 8%-9% unsulfated disaccharide. Potency was inconsistent across groups, which might have resulted from different analytical methods and choice of reference standard. Mean potency obtained by five separate methods ranged from 82.2% to 95.5% for one supplier, 92.5% to 110.1% for another, and 95.1% to 112.5% for a commercially obtained reference standard. Critical issues raised by the results include choice of reference standard, selection of assay method, and the consistent appearance of an unidentifiable contaminant present in all three lots from one supplier. CONCLUSION: This blinded study determined methods to identify acceptable agents and provided results, which, in addition to regulatory compliance supplier audits, formed the basis for chondroitin product selection in GAIT.

Active ingredient consistency of commercially available glucosamine sulfate products.

OBJECTIVE: To assess the content of active ingredient in over-the-counter (OTC) glucosamine sulfate (GLS) preparations. METHODS: We analyzed in a coded, blind manner 14 commercially available capsules or tablets of GLS, plus one herbal mixture as a control. We used a high performance liquid chromatography system as described. RESULTS: The amount of free base varied from 41 to 108% of the mg content stated on the label; the amount of glucosamine varied from 59 to 138% even when expressed as sulfate. CONCLUSION: If GLS is used as a therapeutic agent, it is important that the products conform to a standard in their description. The content is probably best expressed in terms of free base.