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Antimicrobial and Antileishmanial Activities of Hypocrellins A and B. Guoyi Ma, 2004.Hypocrellins A and B were evaluated for in vitro antimicrobial and antileishmanial activities . Hypocrellin A exhibited promising activity against Candida albicans and moderate activity against Staphylococcus aureus, methicillin-resistant S . aureus, Pseudomonas aeruginosa, and Mycobacterium intracellulare . Hypocrellin B showed weak antimicrobial activities . Hypocrellin A exhibited potent antileishmanial activity, while hypocrellin B was only moderately active . These results of promising antifungal and antileishmanial activity of hypocrellin A may be useful for further structure-activity relationship and in vivo studies . Evaluation of Methods for Storage of Marine Macroorganisms with Optimal Recovery of Bacteria. Kathrin Siebert, 2004.Marine macroorganisms are a potential source for new bioactive substances . In many cases marine microorganisms—especially bacteria—associated with these macroorganisms are actually producing the bioactive substances . One often is not able to immediately isolate microorganisms from collected macroorganismic materials; we therefore evaluated different methods for storage of such material, e.g., on board research vessels . These methods were the following: storage of macerates in sintered glass beads and 5% trehalose at –20°C (SGT method); storage of sections in 5% dimethyl sulfoxide at –70°C (SD method); storage of macerates at –20°C using the commercial ROTI-STORE system (RS method); storage of macerates at –20°C in 50% glycerol (GC method); and storage of macerates covered by mineral oil at 4°C (MO method) . The SGT and SD methods resulted in numbers of and especially diversity of recoverable bacteria that were higher than for the other methods . Data for the RS method indicated its potential usefulness, too . The MO method resulted in growth during storage, thereby enriching a few selected microorganisms; the GC method resulted in a survival and diversity of recovered bacteria that was too low . Characterization of Coliphage PR772 and Evaluation of Its Use for Virus Filter Performance Testing. Scott Lute, 2004.Virus filtration is a key clearance unit operation in the manufacture of recombinant protein, monoclonal antibody, and plasma-derived biopharmaceuticals . Recently, a consensus has developed among filter manufacturers and end users about the desirability of a common nomenclature and a standardized test for classifying and identifying virus-retentive filters . The Parenteral Drug Association virus filter task force has chosen PR772 as the model bacteriophage to standardize nomenclature for large-pore-size virus-retentive filters (filters designed to retain viruses larger than 50 to 60 nm in size) . Previously, the coliphage PR772 (Tectiviridae family) has been used in some filtration studies as a surrogate for mammalian viruses of around 50 to 60 nm . In this report, we describe specific properties of PR772 critical to the support of its use for the standardization of virus filters . The complete genomic sequence of virulent phage PR772 was determined . Its genome contains 14,946 bp with an overall G+C content of 48.3 mol%, and 32 open reading frames of at least 40 codons . Comparison of the PR772 nucleotide sequence with the genome of Tectiviridae family prototype phage PRD1 revealed 97.2% identity at the DNA level . By dynamic light-scattering analysis, its hydrodynamic diameter was measured as 82 ± 6 nm, consistent with use in testing large-virus-retentive filters . Finally, dynamic light-scattering analysis of PR772 preparations purified on CsCl gradients showed that the phage preparations are largely monodispersed . In summary, PR772 appears to be an appropriate model bacteriophage for standardization of nomenclature for larger-pore-size virus-retentive filters . Enterococci as Indicators of Lake Michigan Recreational Water Quality: Comparison of Two Methodologies and Their Impacts on Public Health Regulatory Events. Julie Kinzelman, 2003.The frequency of poor-water-quality advisories issued in Milwaukee and Racine, Wisconsin, in the absence of identifiable sources of contamination brought into question the reliability of the present indicator organism, Escherichia coli . Enteroccoci have been suggested as an alternative to E . coli for freshwater monitoring due to their direct correlation to swimmer-associated gastroenteritis . The purpose of this research was threefold: (i) to explore enterococci as an alternative to E . coli for monitoring freshwater Lake Michigan beaches, (ii) to evaluate the impact of the two indicators on regulatory decisions, and (iii) to compare membrane filtration m-enterococcus agar with indoxyl-ß-D-glucoside to a chemical substrate technique (Enterolert) for the recovery of enterococci . Recreational water samples from Milwaukee (n = 305) and Racine (n = 153) were analyzed for the enumeration of E . coli and enterococci using IDEXX Colilert-18 and Enterolert . Correlation between the indicators was low (R2 = 0.60 and 0.69) . Based on U.S . Environmental Protection Agency bacterial indicator threshold levels of risk for full body immersion, using enterococci would have resulted in 56 additional unsafe-recreational-water-quality advisories compared to the total from using E . coli and the substrate-based methods . A comparison of the two enterococcal methods (n = 124) yielded similar results (R2 = 0.62) . This was further confounded by the frequent inability to verify enterococci from those wells producing fluorescence by the defined substrate test using conventional microbiological methods . These results suggest that further research is necessary regarding the use of defined substrate technology interchangeably with the U.S . Environmental Protection Agency-approved membrane filtration test for the detection of enterococci from fresh surface water .
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