Prevalence and Effect of Obesity on Mobility According to Different Criteria in Polio Survivors.

OBJECTIVE: Obesity is a major and functionally important problem in polio survivors. The aim of this study was to investigate the prevalence of obesity using body mass index and percentage body fat in polio survivors and to analyze the relationship between obesity and mobility. DESIGN: Eighty-four polio survivors were included. Anthropometric parameters, knee extensor strength, and the Short Physical Performance Battery were evaluated. A questionnaire was used to explore the late effects of poliomyelitis. Obesity was determined using both body mass index and percentage body fat. RESULTS: The prevalence of obesity in polio survivors was 39.3% and 81.5% using the body mass index and percentage body fat criteria, respectively. The Short Physical Performance Battery scores were significantly different between the obese and nonobese groups as determined by percentage body fat (P < 0.05). Only percentage body fat was significantly associated with mobility after controlling for the confounding variables in obese polio survivors (P < 0.05). CONCLUSIONS: Obesity in polio survivors was underestimated when the body mass index criteria were used. Percentage body fat was a significantly associated factor for mobility in obese polio survivors. Obesity determined by percentage body fat criteria is useful to address obesity-related problems in polio survivors.

Effective screening of Scenedesmus sp. from environmental microalgae communities using optimal sonication conditions predicted by statistical parameters of fluorescence-activated cell sorting.

The effects of the sonication parameters, including the power and time, were investigated for the effective isolation of Scenedesmus sp. from environmental microalgae communities when using fluorescence-activated cell sorting (FACS). The selectivity, defined as the percentage of Scenedesmus sp. successfully isolated and grown in microplates, appeared as peaks in contour plots spanned by the sonication power and time. For fast screening of the optimal sonication conditions, correlations between the selectivity and the statistical parameters from the FACS analysis were investigated. A graphical comparison analysis of the contour plots showed a pattern similarity of over 82% between the coefficients of variation for the side scatter (SSC-CV) and the selectivity. This predictability of the optimal sonication conditions enabled a Scenedesmus sp. selectivity of ca. 2 times using only one-third of the sonication condition sets arbitrarily chosen around the peaks of the SSC-CV, thereby saving resources and time for subsequent processes.

Selection of microalgae for lipid production under high levels carbon dioxide.

To select microalgae with a high biomass and lipid productivity, Botryococcus braunii, Chlorella vulgaris, and Scenedesmus sp. were cultivated with ambient air containing 10% CO(2) and flue gas. The biomass and lipid productivity for Scenedesmus sp. with 10% CO(2) were 217.50 and 20.65 mg L(-1)d(-1) (9% of biomass), while those for B. braunii were 26.55 and 5.51 mg L(-1)d(-1) (21% of biomass). With flue gas, the lipid productivity for Scenedesmus sp. and B. braunii was increased 1.9-fold (39.44 mg L(-1)d(-1)) and 3.7-fold (20.65 mg L(-1)d(-1)), respectively. Oleic acid, a main component of biodiesel, occupied 55% among the fatty acids in B. braunii. Therefore, the present results suggested that Scenedesmus sp. is appropriate for mitigating CO(2), due to its high biomass productivity and C-fixation ability, whereas B. braunii is appropriate for producing biodiesel, due to its high lipid content and oleic acid proportion.

Comparison of several methods for effective lipid extraction from microalgae.

Various methods, including autoclaving, bead-beating, microwaves, sonication, and a 10% NaCl solution, were tested to identify the most effective cell disruption method. The total lipids from Botryococcus sp., Chlorella vulgaris, and Scenedesmus sp. were extracted using a mixture of chloroform and methanol (1:1). The lipid contents from the three species were 5.4-11.9, 7.9-8.1, 10.0-28.6, 6.1-8.8, and 6.8-10.9 g L(-1) when using autoclaving, bead-beating, microwaves, sonication, and a 10% NaCl solution, respectively. Botryococcus sp. showed the highest oleic acid productivity at 5.7 mg L(-1)d(-1) when the cells were disrupted using the microwave oven method. Thus, among the tested methods, the microwave oven method was identified as the most simple, easy, and effective for lipid extraction from microalgae.