We used four strains (Y1, Y2, M1 and M2) to screen out the high lipid production strains. We first adopted cell morphology and cytochemical methods (Sudan III dyeing technique) to observe intracellular characteristics. Observation results indicated that M2 strain had the potential lipid accumulation capacity. To prove this, lipid content of these strains was determined by soxhlet extraction. One strain (M2) was found to produce lipids up to 53.09%. In order to increase the production of oleaginous microorganism, the effects of hydrolysate concentration, nitrogen source, pH, fermentation temperature and time on cell growth and lipid accumulation were studied. The optimal fermentation conditions were obtained as follows: corn starch byproduct hydrolysate concentration at 10(o) Bx as carbon source; NaNO3 as nitrogen source at 0.2%; initial pH of 6.0; temperature at 28 degrees C, cultivated for 6 d. Under these conditions, M2 strain accumulated lipids up to 75.21% on a cellular biomass basis with biomass yield of 30.40 g/L, and the corresponding lipid production reached 22.86 g/L. GC analysis demonstrated that the fatty acid composition of the lipid was similar to that of vegetable oil, which mainly contained 16-and 18-carbon fatty acids. Thus, microbial lipid is a promising material for biodiesel production, and its unsaturated fatty acid content reached around 68%. These unsaturated fatty acids show great potential applications in food, medicine and cosmetics industries.
Biomass ; Culture Media ; Fatty Acids ; analysis ; biosynthesis ; Fermentation ; Hydrogen-Ion Concentration ; Industrial Microbiology ; Starch ; metabolism ; Temperature ; Yeasts ; growth & development ; metabolism

Biomass carbohydrates assimilation and lipid accumulation by Mortierella isabellina M2 strain were investigated. Corn fiber hydrolysate was specially studied. The results showed M. isabellina M2 strain achieved growth and lipid accumulation while glucose, xylose, mannose and arabinose were introduced as single carbon source, respectively. When M. isabellina M2 strain was cultivated on corn fiber hydrolysate with 6% sugars concentration, the biomass reached 18.2 g/L, the lipid content of dry mycelia was 45.7%, and the lipid yield achieved 8.3 g/L. It provided a promising perspective for microbial oils production with biomass hydrolysates.
Biomass ; Carbohydrate Metabolism ; Carbon ; metabolism ; Fermentation ; Industrial Microbiology ; methods ; Lipids ; biosynthesis ; Mortierella ; metabolism ; Zea mays ; metabolism

BACKGROUNDCluster of differentiation 44 (CD44) is a family of transmembrane glycoproteins. As cell surface hyaluronate receptor, it has been found to be widely expressed in a variety of cells. The aim of this study is to assess the relationship among CD44 expression, DNA content, proliferation index (PI) and apoptosis in female adenocarcinoma of the lung.

METHODSThe expression of CD44, DNA index (DI), PI and apoptotic rate were studied in 61 cases of female adenocarcinoma of the lung, paracancerous tissues and 45 cases of benign lesions by flow cytometry.

RESULTSThe percent of DNA aneuploidy was 75.41% in adenocarcinoma. The expression of CD44, DI and PI in adenocarcinoma were significantly higher than those in paracancerous and benign controls (P < 0.01), however the apoptotic rate was obviously lower in adenocarcinoma than that in paracancerous and benign controls (P < 0.01). There was a positive correlation between CD44 and DI (P < 0.01), and a negative correlation between apoptosis and DI in adenocarcinoma (P < 0.01).

CONCLUSIONSThe expression of CD44, DNA content, proliferation and apoptosis may play important regulating roles in oncogenesis, development and metastasis of female adenocarcinoma of the lung.