Advanced Materials Research Vols. 518-523

Abstract: Pseudomonas putida is a safety gammaproteobacterium that plays an important role in bioremediation. Twenty nine mobile genomic islands were accurately localized in four strains of P. putida, six in P. putida F1, six in P. putida GB-1, nine in P. putida KT2440, and eight in P. putida W619, respectively. The integration sites include the tRNA gene, such as tRNAMet gene, tRNASer gene, tRNALeu gene, tRNAGly gene, tRNAThr gene, tRNACys gene, tRNAPro gene, and some structural genes, such as arsenate reductase gene, DNA mismatch repair protein MutS gene, thymidylate synthase gene, and 6-pyruvoyl tetrahydropterin synthase gene. 6-pyruvoyl tetrahydropterin synthase gene was firstly determined as the integration site of the genomic islands. The action sites of the lambda integrases are the stem-loop sequence, and the action sites of the P4 integrase are the asymmetric sequence. KT2440GI-5 can produce R2-type pyocin particle that is a bacteriocin and can kill sensitive bacterium. KT2440GI-9 can code ectoine-induced proteins that cause the cells to survive in high salt concentration.

Abstract: A Gram-positive, strictly aerobic and moderately halophilic bacterial strain HSD was obtained from the sea water sample collected from International Sea Water Bathing Place in Weihai, a city on the shore of the Yellow Sea. Strain HSD was bacillus. The optimum growth temperature was 32~37°C and the optimum pH was 6.0~9.0. It could grow well at 100 g•L-1 salt mass concentration. The G+C mole fraction of its genomic DNA was 37.5%. 16S rRNA gene sequence indicated a close relationship to Alkalibacillus halophilus (DQ359731) with similarity of 99%. However, they had obvious difference in whole-cell main fatty acid components, cell size, cell morphology, motility, oxidase, gelatine liquefication, nitrate reduction, NaCl tolerance range, pH tolerance range, G+C mole fraction, sole carbon source, sole nitrogen source, antibiotic sensitivity and a source of the strain isolation. Comparing of these taxonomic characters of strain HSD with those of other type strains of the genus Alkalibacillus, the differences were more obvious. In view of multiple identification results, it was proposed that strain HSD was classified as the type strain of a new species of the genus Alkalibacillus under the name Alkalibacillus huanghaiensis sp.nov..

Abstract: A Gram-positive, strictly aerobic, spore-bearing and moderately halophilic bacterial strain HNPHT was obtained from the sea mud sample collected from Jinhaitan Park in Weihai, a city on the shore of the Yellow Sea. Strain HNPHT was bacillus. The optimum growth temperature was 30-36°C and the optimum pH was 6.5-9.5. It could grow well at 5-20% salt concentration. The G+C content of its genomic DNA was 37.0%. 16S rRNA gene sequence indicated a close relationship to Alkalibacillus halophilus (DQ359731) and Alkalibacillus salilacus (AY671976) with similarity of 99%. However, they had obvious difference in whole-cell main fatty acid components, cell size, cell morphology, colony color, motility, oxidase, gelatine liquification, nitrate reduction, NaCl tolerance range, pH tolerance range, G+C mole fraction, sole carbon source, sole nitrogen source, antibiotic sensitivity and a source of the strain isolation. A comparison of these taxonomic characters of strain HNPHT with those of some type strains of the genus Alkalibacillus indicated that the strain could be distinguished from A. halophilus and A. salilacus. In view of multiple identification results, it was proposed that strain HNPHT was classified as the type strain of a new species of the genus Alkalibacillus under the name Alkalibacillus weihaiensis sp. nov..

Abstract: In this paper, the effects of the culture water of three types of higher landscape plants Typha latifolia L, Canna indica L and Iris tectorum Maxim on the growth of Chlorella pyrenoidosa have been investigated. The results show that Iris culture water promoted the growth of Chlorella pyrenoidosa, which was facilitated at low contentions and inhibited at high concentrations by the culture water of Canna indica L. Moreover, inhibitory effect of the culture water of Typha latifolia L was the strongest with the rate of 50.7%. Differences of the effects of the three plants on the chlorophyll a contents of Chlorella pyrenoidosa were significant (P Iris tectorum Maxim was utilized, whereas the content was lowest at merely 41% of that of the control group when treated with 80% of the culture water of Typha latifolia L.

Abstract: Although heptachlor epoxide is one of the most persistent organic pollutants (POPs) that cause serious environmental problems, there is very limited information of the biodegradation of heptachlor epoxide by microorganisms, and no systematic study on the metabolic products and pathway of endrin by microorganisms has been conducted. Wood-decay fungi can degrade a wide spectrum of recalcitrant organopollutants, including polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated biphenyls (PCBs). In this study, 18 wood-decay fungi strains of genus Phlebia were investigated for their ability to degrade heptachlor epoxide, and Phlebia acanthocystis, Phlebia brevispora, Phlebia lindtneri and Phlebia aurea removed about 16, 16, 22 and 25% of heptachlor epoxide, respectively, after 14 days of incubation. Heptachlor diol and 1-hydroxy-2,3-epoxychlordene were detected in these fungal cultures as metabolites by gas chromatography and mass spectrometry (GC/MS), suggesting that the hydrolysis reaction in the epoxide ring and substitution of chlorine atom with hydroxyl group in C1 position occur in bioconversion of heptachlor epoxide by selected wood-decay fungi, respectively. This is the first report describing the metabolites of heptachlor epoxide by microorganisms.

Abstract: Bio-drying is an important method to reduce the excess sludge which use the inner biomass of sludge itself to generate heat for a water discharging has a broad prospects in sludge treatment. However, our research in this field is still very limited. In order to better mastering and promoting sludge bio-drying technology, this paper summarized the advantages of bio-drying, initially described the microbial mechanism of spontaneous heat generation and the heat and mass transfer phenomena in a bio-drying process, then build a macro heat conservation formula based on material conservation.

Abstract: In this paper, simulated experiments were performed in pots by using soil materials in different conditions of film remnant. Based on the research on soil microorganism quantity trends of soil enzyme activities were analyzed systematically: soil without film remnant, soil with film remnant for 5, 10, 15 and 20 years. By analyzing crop progress, the relationship with soil material was studied, in order to provide scientific basis for the variation laws between different conditions of film remnant and the activity of soil enzyme.

Abstract: Chromium(Ⅵ) is hazardous to environment. It can be efficiently removed by chromate resistant bacterial consortium. In this study five bacterial strains were isolated and cultured in liquid media containing Cr(Ⅵ) ions. The result shows that they grew better after culturing 24h than 48h and 72h. In the assay removing Cr(Ⅵ) by these strains, all of them presented excellent bioaccumulation abilities. When inital Cr(Ⅵ) ions concentration was 650mg/l, strain 2-7 displayed a best removal potential of 85.8% removal and 24.83 mg/g•h^-1 uptake rate. However, it seemed that the resistance and the removal potential of heavy metal had no direct connection.

Abstract: Heavy metals and atmosphere pollutants that caused the soil pollution and low air quality are main environmental problems in cities which located in the industrialized regions. Different tree species in urban forest ecosystem have absorption ability to heavy metals in the soil and atmosphere pollutant and ameliorate environmental pollution. However, the influence of different tree species on the absorption ability of different pollutant is not yet clear, and this held up selection suitable tree species in urban forest plantations to improve urban environment. In the study we compered pollution absorption ability of 13 tree species in Shenyang, Northeast China. The results showed that, the adsorption capacity of different tree species on pollutants are different. The highest value of Cu was 9.32 mg kg^-1 found in Berberisthumbergii cv. Atropurpurea, Zn was 51.461 mg kg^-1 in Pinus bungeana, Pb was 7.459 mg kg^-1 in Malus pumila Mill, Cr was 9.841 mg kg^-1 in Buxus microphylla, S was 8916.07 mg kg^-1 in Salix babylonica, Zn was 4678.388 mg kg^-1 in Buxus microphylla. Pollutant concentrations in the same plant species are different in 3 different sample sites. This indicate the contaminated degree of 3 sample sites were different. In our study, Huigong square pollution degree is serious than the Beiling Park and Huishan ecological park. Significant correlation was found between Cu and Cr, Cu and Cl, S and Zn, Cr and Cl (P<0.01) and that between Cu and Zn, Cu and Pb at 0.05 level. The relationship between heavy metals and atmosphere pollutant (S and Cl) indicated that traffic activities could be one of the dominant roles of heavy metal and atmosphere pollution in Shenyang City.