a solid state fermentation method was used to utilize wheat straw as substrates for citric acid production by using aspergillus niger atcc 9142. the plackett burman design (pbd) of experiments was used to test the relative importance of the variables affecting production such as moisture content, age of spore, inoculum size, initial ph of substrate, methanol concentration, incubation temperatur...

Increasing demand for plant oil for food, feed, and fuel production has led to food-fuel competition, higher plant lipid cost, and more need for agricultural land. On the other hand, the growing global production of biodiesel has increased the production of glycerol as a by-product. Efficient utilization of this by-product can reduce biodiesel production costs. We engineered Yarrowia lipolytica...

Twenty-seven Yarrowia lipolytica strains as well as five strains from three other species of the Yarrowia clade (Aciculoconidium aculeatum, andida hispaniensis and Candida bentonensis) were screened for citric acid production with pure glycerol as the carbon source. The cultures were rown under nitrogen-limited conditions. None of the non-Yarrowia strains produced citric acid, although they wer...

Fungi isolated from various rotten fruits and vegetables were screened for the capability of producing citric acid. Aspergillus niger (A. niger) was obtained in the decayed onion peels and denoted as KON13 and this fungi strain was used in the production of citric acid by submerged fermentation. Critical process parameters affecting the fermentative citric acid production were investigated, inc...

The possible use of cotton waste as a carbohydrate source of citric acid production by Aspergillus niger was examined. No citric acid was produced when A. niger was grown on cotton waste as a sole carbon source. In two-stage fermentations, however, mycelium obtained from surface cultures in cotton waste medium yielded more citric acid when transferred to sucrose-containing media than when direc...

The mutant strain of Aspergillus niger NG-110 was evaluated for the present investigation of citric acid production. The cultural conditions optimized during the course of study were pH and K4Fe(CN)6, K2HPO4 and CaCl2 concentrations. Cane-molasses was utilized as the basal fermentation medium. The mutant NG-110 produces maximal amount of citric acid when the pH of the medium was 6. When the con...

S t e i n b e r g (1935) and L u n d (1953) found that the growth of Aspergillus niger is influenced by copper. O r 1 o v et al. (1968) have further observed that 10.0% solution of copper sulphate increases markedly the yield of citric acid when molasses is employed as substrate. T o m l i n s o n et al (1950) studied the influence of Zn, Fe, Mn and Cu on the production of citric acid and obser...

BACKGROUND C4-dicarboxylic acids, including malic acid, fumaric acid and succinic acid, are valuable organic acids that can be produced and secreted by a number of microorganisms. Previous studies on organic acid production by Aspergillus carbonarius, which is capable of producing high amounts of citric acid from varieties carbon sources, have revealed its potential as a fungal cell factory. Ea...

The possibility of using glycerol and glycerol-containing waste from biodiesel manufacture as a carbon and energy source for microbiological production of citric acid has been studied. Acid formation on the selective media had previously been tested in 66 yeast strains of different genera (Candida, Pichia, Saccharomyces, Torulopsis and Yarrowia). Under growth limitation by nitrogen, 41 strains ...