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After the lipid contents in 7 strains of Rhodosporidium toruloides were determined, R. toruloides 21167 among them was found to be able to produce the highest amount of lipid in its cells. Many ions, such as Mn 2+ , Ca 2+ , Zn 2+ and Fe 3+ had positive effects on lipid accumulation by R. toruloides 21167. After the yeast was cultivated in the medium containing 8.0% cassava starch hydrolysate for 144 h at flask level, cell mass, lipid content, residual reducing sugar and residual total sugar in the culture reached 18.5 g m −3 , 63.2% (w/w), 15.0 g m −3 and 3.2 g m −3 , respectively, while after it was grown in the same medium by 2-l fermentation for 192 h, cell mass, lipid content, residual reducing sugar and residual total sugar in the culture reached 22.0 g m −3 , 63.4% (w/w), 5.4 g m −3 and 0.5 g m −3 , respectively. The results also showed that most of the sugar added to the medium was utilized by R. toruloides 21167 for cell growth and lipid accumulation. Over 96.8% of the fatty acids from the yeast strain 21167 was C 16:0 , C 18:0 , C 18:1 and C 18:2 , especially C 18:1 (53.34%). The biodiesel obtained from the produced lipid could be burnt well.

In this work, the anti-Escherichia coli activity of the bioactive substances produced by Bacillus amyloliquefaciens R3 was examined. A new and cheap medium for production of the anti-E. coli substances which contained 20.0 g L(-1) soybean powder, 20.0 g L(-1) wheat flour, pH 6.0 was developed. A crude surfactant concentration of 0.48 mg mL(-1) was obtained after 27 h of 10-L fermentation, and the diameter of the clear zone on the plate seeded with the pathogenic E. coli 2# was 23.3 mm. A preliminary characterization suggested that the anti-E. coli substances produced by B. amyloliquefaciens R3 were the biosurfactins (F1, F2, F3, F4, and F5) with amino acids (GLLVDLL) and hydroxy fatty acids (of 12-15 carbons in length). It was found that all the strains of the pathogenic E. coli showed resistance to several different antibiotics, suggesting that they were the multi-drug resistance and all the strains of the pathogenic E. coli were sensitive to the biosurfactins, indicating that the biosurfactins produced by B. amyloliquefaciens R3 had a broad spectrum of antibacterial activity against the pathogenic E. coli with multi-drug resistant profiles. After the treatment with the purified biosurfactin (F1), the cell membrane of both the whole cells and protoplasts of the E. coli 2# was damaged and the whole cells of the bacterium were broken.

In this work, the antibacterial activity of the lipopeptides produced by Bacillus amyloliquefaciens M1 was examined against multidrug-resistant Vibrio spp. and Shewanella aquimarina isolated from diseased marine animals. A new and cheap medium which contained 1.0 % soybean powder, 1.5 % wheat flour, pH 7.0 was developed. A crude surfactant concentration of 0.28 mg/ml was obtained after 18 h of 10-l fermentation and diameter of the clear zone on the plate seeded with Vibrio anguillarum was 34 mm. A preliminary characterization suggested that the lipopeptide N3 produced by B. amyloliquefaciens M1 was the main product and contained the surfactin isoforms with amino acids (GLLVDLL) and hydroxy fatty acids (of 12–15 carbons in length). The evaluation of the antibacterial activity of the lipopeptide N3 was carried out against S. aquimarina and nine species of Vibrio spp.. It was found that all the Vibrio spp. and S. aquimarina showed resistance to several different antibiotics, suggesting that they were the multidrug resistance. It was also indicated that all the Vibrio spp. strains and S. aquimarina were sensitive to the surfactin N3, in particular V. anguillarum. The results demonstrated that the lipopeptides produced by B. amyloliquefaciens M1 had a broad spectrum of action, including antibacterial activity against the pathogenic Vibrio spp. with multidrug-resistant profiles. After the treatment with the lipopeptide N3, the cell membrane of V. anguillarum was damaged, and the whole cells of the bacterium were disrupted.

The bacterium Bacillus amyloliquefaciens anti-CA isolated from mangrove system was found to be able to actively kill Candida albicans isolated from clinic. The bacterial strain anti-CA could produce high level of bioactive substance, amylase and protease in the cheap medium containing 2.0 % soybean meal, 2.0 % wheat flour, pH 6.5 within 26 h. After purification, the main bioactive substance was confirmed to be a cyclic lipopeptide containing a heptapeptide, L-Asp→L-Leu→L-Leu→L-Val→L-Val→L-Glu→L-Leu and a 3-OH fatty acid (15 carbons). In addition to C. albicans, the purified lipopeptide can also kill many yeast strains including Metschnikowia bicuspidata, Candida tropicalis, Yarrowia lipolytica and Saccharomyces cerevisiae. After treated by the purified lipopeptide, both the whole cells and protoplasts of C. albicans were destroyed.

Because RST's ablity of data reduction, feature subset selection was translated into the process of data reduction. The condition attributes and decidation attributes of the diagnosis system were reducted, and we received the best training swatch which were cleared up the information of redundance and repetition. Greedy algorithm is a method of discretion and a algorithm of attribute reduction. In the article, fault diagnosis data of roller bearing was discreted and was reducted its attribute. The simple and reliable diagnosis rulers were received, and testing samples ralidated the reliability of the rulers.