Search

With fossil fuel sources in limited supply, microalgae show tremendous promise as a carbon neutral source of biofuel. Current microalgae biofuel strategies typically rely on growing high-lipid producing laboratory strains of microalgae in open raceways or closed system photobioreactors. Unfortunately, these microalgae species are found to be sensitive to environmental stresses or competition by regional strains. Contamination by invasive species can diminish productivity of commercial algal processes. A potential improvement to current strategies is to identify high-lipid producing microalgae, which thrive in selected culture conditions that reduce the risk of contamination, such as low pH. Here we report the identification of a novel high-lipid producing microalgae which can tolerate low pH growth conditions. Lig 290 is a Scenedesmus spp. isolated from a low pH waterbody (pH = 4.5) in proximity to an abandoned lignite mine in Northern Ontario, Canada. Compared to a laboratory strain of Scendesmus dimorphus, Lig 290 demonstrated robust growth rates, a strong growth profile, and high lipid production. As a consequence, Lig 290 may have potential application as a robust microalgal species for use in biofuel production.

Neuraminidase was produced by 32.1% and 28.5% of Porphyromonas from dogs with and without periodontitis, respectively; and by 31.8% of bacteria from humans. The presence of neuraminidase in Porphyromonas spp. suggests that this enzyme can be involved with the pathogenesis of the periodontal disease, and the use of this assay to detect the neuraminidase production in oral Porphyromonas species is suggested., (© 2013.)

The occurrence of Porphyromonas gulae, Porphyromonas macacae, Fusobacterium nucleatum and Fusobacterium canifelinum in subgingival plaque from dogs with and without periodontitis as well as their antimicrobial susceptibility were evaluated. From 50 dogs with periodontitis were identified 38 P. gulae, 8 P. macacae, 26 F. nucleatum and 15 F. canifelinum, and from 50 dogs without periodontitis were identified 15 P. gulae, 12 F. nucleatum and 11 F. canifelinum. All strains were susceptible to most of the antibiotics tested, however, different resistance rates to clarithromycin, erythromycin and metronidazole among strains were observed. The role of P. gulae, P. macacae, F. nucleatum and F. canifelinum in periodontal disease of household pets needs to be defined to a better prevention and treatment of the canine periodontitis., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A rapid PCR approach was developed to detect Porphyromonas gulae strains from subgingival samples of dogs with and with periodontitis. The presence of P. gulae was observed in 92% and 56%, respectively, in dogs with and without periodontitis. The new primer pair was specific to detect this microorganism, and this technique could be used to evaluate a correlation between periodontitis and P. gulae in companion animals., (Copyright © 2011 Elsevier Ltd. All rights reserved.)