Papers by Keyword: Heterotrophic

Abstract: The impact of glucose on the growth under heterotrophic and mixotrophic conditions for Monoraphidium sp. FXY-10 as well as its lipid content was investigated through the Andrew equation. The results demonstrated that the subsaturation constant of Monoraphidium sp. FXY-10 under heterotrophic condition to glucose was smaller than that of Monoraphidium sp. FXY-10 under mixotrophic condition, indicating that Monoraphidium sp. FXY-10 is more sensitive to glucose under heterotrophic condition. Furthermore, the biomass productivity, lipid productivity and lipid content of Monoraphidium sp. FXY-10 all reached the peak at 10 g L-1 of glucose concentration under both heterotrophic and mixotrophic conditions. Compared with other Chlorella sp., the Monoraphidium sp. FXY-10 represented higher lipid productivity (131.79 mg L^-1 d^-1).

Abstract: Nostoc flagelliforme is a kind of terrestrial cyanobacterium with high economic value. Dissociated cells, which separated from a natural colony of N. flagelliforme, could be cultivated heterotrophically in the darkness on xylose and glucose under fed-batch culture conditions. Growth and extracellular polysaccharides (EPS) production in different cultures are investigated. At harvest time, the cultures contain 1.215 g•L-1 of biomass and 122.5 mg•L-1 of EPS respectively. The gravimetric EPS production rate is 17.5 mg•g-1•day-1, which is 1.65 times higher than previously reported results for heterotrophic Nostoc flagelliforme grown on xylose batch culture.

Abstract: Identifying influential factors in the bacterial leaching of nickel laterites using a mixed culture of chemolithotrophic micro-organisms was explored using the approach of statistical design of experiments. In a series of experiments, pH, particle size, pulp density, type of substrate and inoculum size were statistically combined using a quarter fractional factorial designs 2 5−2 III and tested for their influence on nickel recovery using chemolithotrophic microorganisms. The results indicated that inoculum size was not statistically significant while the rest of the factors were statistically significant. Under the ranges studied the interaction between the variables was found to be weak. The results also showed that recovery was maximized at low pH and low pulp density. In the range studied, particles of less than 38μm had a negative influence on nickel recovery. Sulphur substrate also showed better effects than pyrite.