An axenically cultured isolate of single-celled freshwater microalgae (Chlorella sp.) metabolized toxic selenate to volatile dimethylselenide at exceptionally high rates when transferred from mineral-nutrient solution to water for 24 h. The Se-volatilization rates were orders of magnitude higher than those similarly measured for wetland macroalgae and higher plants. Ninety percent of 20 micro m...

A one-step process was applied to directly converting wet oil-bearing microalgae biomass of Chlorella pyrenoidosa containing about 90% of water into biodiesel. In order to investigate the effects of water content on biodiesel production, distilled water was added to dried microalgae biomass to form wet biomass used to produce biodiesel. The results showed that at lower temperature of 90°C, wate...

Chlorella vulgaris (Chlorophyta, Chlorophyceae) has received a particular attention in the programmes of microalgae utilisation in biotechnology. Enzymatic hydrolysis of cell proteins represents a very promising method to increase protein digestibility and thus, for obtaining hydrolysates with improved nutritional and functional properties. However, this technology has been little approached an...

Nitrogen starvation is an efficient environmental pressure for increasing lipid accumulation in microalgae, but it could also significantly lower the biomass productivity, resulting in lower lipid productivity. In this study, green alga Chlorella sp. A2 was cultivated by using a minimal nitrogen supply strategy under both laboratory and outdoor cultivation conditions to evaluate biomass accumul...

Nitrogen (N) and sulphur (S), being essential macronutrients, have important roles in microalgae metabolism. Effects of Nor S-shortage were investigated in the green microalgae Chlorella sorokiniana subjected to 24 h of starvation, by measuring the glutamine synthetase (GS) and O-acetylserine(thiol)lyase (OASTL) activities, proteins and amino acids levels. To test possible metabolic impact rela...

To contribute the biological mean of CO2 fixation, more than 200 microalgal isolates were screened from lakes, ponds, sediments, hog wastewater, paddy fields, hot springs, and seawater in Taiwan. Two unicellular microalgae, Chlorella sp. NTU-H15 and Chlorella sp. NTU-H25, were isolated from hog wastewater. In the laboratory, they were able to grow up even in aeration containing CO2 up to 40% an...

Rice straw hydrolysate was used as lignocellulose-based carbon source for Chlorella pyrenoidosa cultivation and the feasibility of in situ biodiesel production was investigated. 13.7 g/L sugar was obtained by enzymatic hydrolyzation of rice straw. Chlorella pyrenoidosa showed a rapid growth in the rice straw hydrolysate medium, the maximum biomass concentration of 2.83 g/L was obtained in only ...

From the ethyl acetate extract of the strain Streptomyces sp. isolate GW23/1540, besides 16 known products, several 1H-quinazolin-4-one derivatives were isolated. (SR)-2-(1-Hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (4) and (RR)-2-(1-hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (5) are new natural products. 2-Methyl-3H-quinazolin-4-one (2) and 1H-quinazoline-2,4-dione (3) ...

Current toxicity tests with microalgae are often criticized as being overly sensitive to metals because algae are cultured in metal-deficient media. If such bioassays overestimate copper toxicity in surface waters, the relevance of water quality guidelines derived from these tests is questionable. In this study, the effect of acclimation to copper at environmentally relevant concentrations, on ...