Subject(s)
Humans , Female , Middle Aged , Seroma/complications , Seroma/diagnosis , Seroma/microbiology , Lymphopenia/complications , Lymphopenia/physiopathology , Lymphopenia , Geotrichum/isolation & purification , Geotrichum/pathogenicity , Abdominal Pain/etiology , Amoxicillin-Potassium Clavulanate Combination/therapeutic use , Seroma/physiopathology , Seroma , Geotrichum/radiation effects , Geotrichum/ultrastructure , Diagnosis, DifferentialABSTRACT
This study evaluates the application of low magnetic field (LMF) on inulinase enzyme production by Geotrichum candidum under solid state fermentation (SSF) using leek as potential carbon source. First, the fermentation conditions were optimized using normal magnetic field grown microorganism. Among eight G. candidum isolates, the most effective strain called G. candidum OC-7 was selected to use in further experiments. In the second part of the study, SSF was carried out under different LMFs (4 and 7 mT). The results showed that inulinase activity was strongly affected by LMF application. The highest enzyme activity was obtained as 535.2 U/g of dry substrate (gds) by 7 mT magnetic field grown G. candidum OC-7. On the contrary, the control had only 412.1 U/gds. Consequently, the use of leek presents a great potential as an alternative carbon source for inulinase production and magnetic field treatment could effectively be used in order to enhance the enzyme production.
Subject(s)
Geotrichum/metabolism , Geotrichum/radiation effects , Glycoside Hydrolases/biosynthesis , Magnetic Fields , Onions/microbiology , Analysis of Variance , Bioreactors/microbiology , Fermentation/radiation effects , Geotrichum/enzymology , Glycoside Hydrolases/metabolismABSTRACT
To obtain an industrial strain with high lipid yield, the wild strain G0 of Geotrichum robustum was mutated by means of nitrogen ions implantation. Mutagenic effects of strain G0 by low energy N+ ion implantation were studied. The experimental results indicated that the survival rate curve took a "saddle" shape, and the positive mutation rate was increased to 22.00 percent at the dose of nitrogen ions 2.0 x 10(15) ions/cm² when the survival rate was 28.60 percent. By repeated screening, a high lipid producing strain G9 was obtained. The biomass, lipid content and lipid yield of the mutant can reach 40.25 g/L, 71.14 percent and 28.63 g/L after cultured in a 5L fermenter for 8 days, increasing by 52.81 percent, 68.82 percent and 157.93 percent to those of wild strain, respectively. Analysis results on fatty acids composition and relative content by gas chromatography and mass spectrometry showed that the lipid in strain G9 was mainly composed of 16-carbon and 18-carbon fatty acids, including 37.360 percent oleic acid, 23.631 percent palmitic acid, 4.458 percent linoleic acid and 26.465 percent stearic acid. Such compositional features were quite similar to plant oil. Geotrichum robustum strain G9 may be an ideal high lipid producing strain for biodiesel production.
