Case report. Efficacy of Hoodia for weight loss: is there evidence to support the efficacy claims?

Increasing rates of adult obesity and its negative health consequences are likely to become an increasing burden to the Canadian health care system. Consumers are looking for treatment options and often try the natural health products that are heavily promoted as safe, fast and effective. In this case report, MH, a 57-year-old overweight female wanted advice regarding whether she should use the natural product Hoodia to help her attain her weight loss goals. A literature search was conducted using Medline, EMBASE, the Cochrane Library, Natural Medicines Comprehensive Database and IPA from inception to March 2009. The internet, files of the authors and bibliographies of articles were searched for additional references. No published, peer-reviewed randomized controlled trials examining efficacy of Hoodia were found. Unpublished data from two small trials reported promising results with no adverse events. However, this leaves many unanswered questions regarding the use of Hoodia for weight loss such as the appropriate dose and duration, short and long term safety and use in patients with concomitant diseases. Literature suggests that some commercial products may not actually contain Hoodia at all. Additionally, Hoodia is not yet listed in the Canadian Licensed Natural Health Products Database meaning products sold in Canada may not meet Canadian regulatory standards. Upon discussing this information, MH decided not to use Hoodia, and other evidence-based recommendations were discussed.

L-741,494, a fungal metabolite that is an inhibitor of interleukin-1 beta converting enzyme.

gamma-Pyrone-3-acetic acid (L-741,494) is a novel metabolite produced by a culture of the fungal genus Xylaria. This substance is a water-soluble, competitive, irreversible inhibitor of Interleukin-1 beta Converting Enzyme that is inactive against papain and trypsin. It has a mol wt of 154 and an empirical formula of C7H6O4. We propose the name xylaric acid for this compound.

Novel nematocidal agents from Curcuma comosa.

Curcuma comosa is a member of the economically important plant family, Zingiberaceae. A methanolic extract of C. comosa was shown to be nematocidal when tested against the free-living nematode Caenorhabditis elegans. Five diphenylheptanoids [1-5], one new and four known, have been isolated and shown to be responsible for the activity. This is the first report of three of these compounds [1, 2, 4] being isolated from a natural source.

The metabolism of muzigadial by microorganisms.

1. A total of 114 microorganisms were evaluated for their ability to metabolize the antifungal drimane sesquiterpene, muzigadial. 2. Cryptococcus neoformans was found to convert muzigadial to one major metabolite, identified as a hemiacetal. 3. Streptomyces platensis produced three metabolites: the hemiacetal, its corresponding lactone, and the epoxide of the hemiacetal. 4. Streptomyces spectabilis produced the hemiacetal as well as the epoxy hemiacetal. 5. The proposed structures of all of the metabolites were based on comparisons of the spectroscopic data (1H- and 13C-n.m.r. spectra and mass spectra) between the metabolites and the parent compound. 6. Antimicrobial evaluation of the microbial metabolites indicate that metabolism decreases antifungal activity.

Microbial production of a crisnatol metabolite.

Microbial metabolism studies of crisnatol (1), a new DNA intercalator, has resulted in the isolation and characterization of a major metabolite identified as the C-1 hydroxylated crisnatol (2). The structure of the metabolite was established by comparison of its spectral data to that of crisnatol. Complete 13C-NMR assignments for crisnatol and its C-1 hydroxylated metabolite were also made.

The metabolism of CGP-291: the use of microorganisms as models of mammalian metabolism.

CGP-291 is an investigational antiprotozoal agent with unknown metabolism. Microbial systems were utilized, as a model of mammalian metabolism, to predict the oxidative metabolic pathway of this nitroimidazole. Large-scale fermentation of CGP-291 with Beauvaria bassiana produced two major metabolites, IV and V. Structures of both were elucidated by comparing spectral data of metabolites to that of the starting material. The presence of two minor monohydroxylated metabolites was verified using LC-MS.