Exposure to narrowband violet-blue light around 405 nm wavelength can induce lethal oxidative damage to bacteria and fungi, however effects on viruses are unknown. As photosensitive porphyrin molecules are involved in the microbicidal inactivation mechanism, and since porphyrins are absent in viruses, then any damaging effects of 405 nm light on viruses might appear unlikely. This study used th...

Dissolved nutrient concentrations in natural waters may at times be controlled by interactions between particulate and solution phases. Effects of Zn [O-l PM total Zn(II)] and orthophosphate (8-12 PM total P) additions on growth indices for the chlorophyte Selenastrum capricornutum Printz were examined in a synthetic growth medium containing 50 mg liter-l colloidal titania. Over the Zn(H) conce...

Cellular nutrient ratios are often applied as indicators of nutrient limitation in phytoplankton studies, especially the so-called Redfield ratio. For periphyton, similar data are scarce. We investigated the changes in cellular C : N : P stoichiometry of benthic microalgae in response to different levels and types of nutrient limitation and a variety of abiotic conditions in laboratory experime...

Indigenous acidophilic bacteria separated from mine-waste can be used in return for the addition of the reagents like sulfuric acid. Among the tailings bacteria, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans are of the most-studied ones for the bioleaching and bioremediation of elements. In this work, the isolation and characterization of the mentioned bacteria are studied by...

phosphorus induces flowering and helps seed formation, but there is a big gap between phosphorus supply from natural sources and agriculture and industry demand. in order to investigate phosphorus feeding over long time from iran regions' apatites on rose plants characteristics, var. black magic in zeoponic culture, an experiment was conducted as factorial on the basis of completely random...

Background: Cell ability to recover from radiation damage is of great relevance in cancer treatment. It is often believed that the inhibition of cell ability to the liquid holding recovery (LHR) may be an indicator of the overall suppression of cell ability to recover from potentially lethal radiation damage. However, the literature contains no experimental evidence whether the LHR inhibition m...

Catalases are efficient scavengers of H2O2 and protect cells against H2O2 stress. Examination of the H2O2 stimulon in Saccharomyces cerevisiae revealed that the cytosolic catalase T (Ctt1) protein level increases 15-fold on H2O2 challenge in synthetic complete media although previous work revealed that deletion of the CCT1 or CTA1 genes (encoding peroxisomal/mitochondrial catalase A) does not i...