a r t i c l e i n f o Background: The production of algal-derived oil has been recognized as an expanding new industry. Algal oil recovery and quality are impacted by both biological (algal cell type, growth physiology) and technical (recovery and extraction methodologies) constraints. Unfortunately, and unlike other well-established food and oil commodities , presently no universal reference s...

The vast majority of nanotoxicity studies measures the effect of exposure to a toxicant on an organism and ignores the potentially important effects of the organism on the toxicant. We investigated the effect of citrate-coated silver nanoparticles (AgNPs) on populations of the freshwater alga Chlamydomonas reinhardtii at different phases of batch culture growth and show that the AgNPs are most ...

The influence of irradiance and iron (Fe) supply on phytoplankton processes was investigated, north (47øS, 142øE) and south (54øS, 142øE) of the Subantarctic Front in austral autumn (March 1998). At both sites, resident cells exhibited nutrient stress (Fv/ F m < 0.3). Shipboard perturbation experiments examined two light (mean in situ and elevated) and two Fe (nominally 0.5 and 3 nM) treatments...

Most phylloid algal mounds are currently interpreted as no more than accumulations of leaf-like thalli supported by mud. We report here phylloid algae from the Upper Pennsylvanian (Late Carboniferous) Frisbie Limestone Member in Kansas, USA, which built small mounds with recognizable primary topographic relief. Cup-shaped algal thalli, growing closely packed and juxtaposed near and above one an...

A closed-system algal toxicity test with no headspace was applied to evaluate the toxicity of chlorophenols to Pseudokirchneriella subcapitata. The dissolved oxygen production and the growth rate based on cell density were the response endpoints. Phenol and seven chlorophenols were tested using the above test technique. Median effective concentrations (EC50) range from 0.004 to 25.93 mg/l (base...

The present work describes the optimization of a short-term assay, based on the inhibition of the esterase activity of the alga Pseudokirchneriella subcapitata, in a microplate format. The optimization of the staining procedure showed that the incubation of the algal cells with 20 μmolL fluorescein diacetate (FDA) for 40 min allowed discrimination between metabolic active and inactive cells. Th...

Lake Dianchi is a shallow and turbid lake, located in Southwest China. Since 1985, Lake Dianchi has experienced severe cyanabacterial blooms (dominated by Microcystis spp.). In extreme cases, the algal cell densities have exceeded three billion cells per liter. To predict and elucidate the population dynamics of Microcystis spp. in Lake Dianchi, a neural network based model was developed. The c...

Coccomyxa acidophila is an extremophile eukaryotic microalga isolated from the Tinto River mining area in Huelva, Spain. Coccomyxa acidophila accumulates relevant amounts of β-carotene and lutein, well-known carotenoids with many biotechnological applications, especially in food and health-related industries. The acidic culture medium (pH < 2.5) that prevents outdoor cultivation from non-desire...

Biosorption of heavy metals using dried algal biomass has been extensively described but rarely implemented. We contend this is because available algal biomass is a valuable product with a ready market. Therefore, we considered an alternative and practical approach to algal bioremediation in which algae were cultured directly in the waste water stream. We cultured three species of algae with an...