Biosorption of Uranyl Ions from Aqueous Solution by Parachlorella sp. AA1.

In the present study we investigated the ability of the microalgal strain Parachlorella sp. AA1 to biologically uptake a radionuclide waste material. Batch experiments were conducted to investigate the biosorption of uranyl ions (U(VI)) in the 0.5-50.0 mg/L concentration range by strain AA1. The results showed that AA1 biomass could uptake U(VI). The highest removal efficiency and biosorption capacity (95.6%) occurred within 60 h at an initial U(VI) concentration of 20 mg/L. The optimum pH for biosorption was 9.0 at a temperature of 25 °C. X-ray absorption near edge structure analysis confirmed the presence of U(VI) in pellets of Parachlorella sp. AA1 cells. The biosorption methods investigated here may be useful in the treatment and disposal of nuclides and heavy metals in diverse wastewaters.

The LAMMER kinase is involved in morphogenesis and response to cell wall- and DNA-damaging stresses in Candida albicans.

Dual specificity LAMMER kinase has been reported to be conserved across species ranging from yeasts to animals and has multiple functions. Candida albicans undergoes dimorphic switching between yeast cells and hyphal growth forms as its key virulence factors. Deletion of KNS1, which encodes for LAMMER kinase in C. albicans, led to pseudohyphal growth on YPD media and defects in filamentous growth both on spider and YPD solid media containing 10% serum. These cells exhibited expanded central wrinkled regions and specifically reduced peripheral filaments. Among the several stresses tested, the kns1Δ strains showed sensitivity to cell-wall and DNA-replicative stress. Under fluorescent microscopy, an increase in chitin decomposition was observed near the bud necks and septa in kns1Δ cells. When the expression levels of genes for cell wall integrity (CWI) and the DNA repair mechanism were tested, the kns1 double-deletion cells showed abnormal patterns compared to wild-type cells; The transcript levels of genes for glycosylphosphatidylinositol (GPI)-anchored proteins were increased upon calcofluor white (CFW) treatment. Under DNA replicative stress, the expression of MluI-cell cycle box binding factor (MBF)-targeted genes, which are expressed during the G1/S transition in the cell cycle, was not increased in the kns1 double-deletion cells. This strain showed increased adhesion to the surface of an agar plate and zebrafish embryo. These results demonstrate that Kns1 is involved in dimorphic transition, cell wall integrity, response to DNA replicative stress, and adherence to the host cell surface in C. albicans.

Beneficial effects of fresh and fermented kimchi in prediabetic individuals.

BACKGROUND: With the increased incidence of diabetes mellitus, the importance of early intervention in prediabetes has been emphasized. We previously reported that fermented kimchi, a traditional Korean food, reduced body weight and improved metabolic factors in overweight participants. We hypothesized that kimchi and its fermented form would have beneficial effects on glucose metabolism in patients with prediabetes. METHODS: A total of 21 participants with prediabetes were enrolled. During the first 8 weeks, they consumed either fresh (1-day-old) or fermented (10-day-old) kimchi. After a 4-week washout period, they switched to the other type of kimchi for the next 8 weeks. RESULTS: Consumption of both types of kimchi significantly decreased body weight, body mass index, and waist circumference. Fermented kimchi decreased insulin resistance, and increased insulin sensitivity, QUICKI and disposition index values (p = 0.004 and 0.028, respectively). Systolic and diastolic blood pressure (BP) decreased significantly in the fermented kimchi group. The percentages of participants who showed improved glucose tolerance were 9.5 and 33.3% in the fresh and fermented kimchi groups, respectively. CONCLUSIONS: Consumption of kimchi had beneficial effects on glucose metabolism-related and anthropometric factors in participants with prediabetes. Fermented kimchi had additional effects on BP and insulin resistance/sensitivity. The percentage of participants who showed improvement in glucose tolerance was high in the fermented kimchi group.