Advanced Materials Research Vols. 518-523

Abstract: Genetic diversity of 11 intestinal aerobic bacteria isolated from Dendrolimu. kikuchii was analysed, using PCR and ARDRA which used enzyme digestion of cloned 16S rRNA gene sequences. The results showed that 11 strains could be divided into 6 groups on 84% similarity level, it indicated that the intestinal aerobic bacteria genetic diversity was abundant. Sequencing the 6 representative strains’ 16S rDNA and submitting to GenBank, the accession number being JQ308104 to JQ308109 respectively. The 6 strains belonged to Klebsiella sp., Lysinibacillus sp., Brevibacillus sp., Bacillus subtilis, Gamma Proteobacterium and Brevibacillus limnophilus.

Abstract: The thermostability and catalytic activity of endoglucanase from thermophilic Thermotoga maritima were improved by evolutionary molecular engineering. The cel12B gene from Thermotoga maritima was cloned and expressed, and the expressed Cel12B protein was purified by His-tag affinity chromatography. The constructed plasmids were screened on LB plate with ampicillin using Escherichia coli BL21 (DE3) as a host. The results showed that both the enzyme activity and yield of the Cell12B protein expressed in pET15b-cel12B were 2 times as that of the protein expressed in pET20b-cel12B.

Abstract: Cytochrome P450 monooxygenases are enzymes which are capable of oxidising saturated and unsaturated substrates. P450BM3 from Bacillus megaterium is one of this family. For the first time, the cyp gene for coding P450BM3 from B. megaterium ALA2 has been cloned and expressed in Escherichia coli. The recombinant enzyme is 120 kDa, containing 1049 aa. The highest activity of purified enzyme is 14.8 U/mg towards palmitic acid by monitoring the NADPH oxidation. The optimal pH and temperature were 9.0 and 40°C. The enzyme has higher activity towards linoleic acid, and 2-Methyl-7-octadecene can also be catalyzed which is a precursor of displar.

Abstract: Under hydroponics, shoots of the copper (Cu) accumulator Elsholtzia haichowensis after 100 μM CuSO4 treatment 6 day were additionally treated with different inhibitors, then the effects of Cu and inhibitors on antioxidant enzyme activities in leave cells of E. haichowensis were investigated. Our results showed that Cu treatment significantly increased the activities of plasma membrane–bound NADPH oxidase, apoplastic peroxidase, apoplastic superoxide dismutase (SOD), symplastic SOD and symplastic ascorbate peroxidase in leaves of E. haichowensis. When additional treatment with N-N-diethyldithiocarbamate as an inhibitor of SOD, NaN3 as an inhibitor of peroxidase, diphenyleneiodonium as an inhibitor of NADPH oxidase and1,2-dihydroxybenzene-3,5-disulphonic acid as an O2•– scavenger, the activities of Cu-induced antioxidant enzymes in leave cells of E. haichowensis were significantly inhibited. The results showed that Cu-induced increase in the activities of various antioxidant enzymes in different cell compartments may represent a defense mechanism against oxidative stress.

Abstract: Caragana Korshinskii Kom is a widely grown deciduous shrub in the region of inner magnolia. A full utilization of its useful components holds great potential for cellulosic ethanol production in an efficient and economic way. The remaining residues after protein extraction contain 29.02% cellulose and 19.61% hemicellulose, offers a potential feedstock for cellulosic ethanol production. Fermentable capability of hydrolysate derived from pretreated biomass is strongly dependent on pretreatment methods. In this work, three hydrolysis methods (alkaline hydrolysis, acid hydrolysis and acid-alkali hydrolysis) were compared by its digestibility. Alkali pretreatment could help greatly to cellulose degradation. The conversion percentage of cellulose and hemicellulose was increased to 1.43% and 13.01%, respectively. Without any nutrient addition, hydrolysate from alkaline pretreated biomass showed relative fermentable capability by Candida Tropicalis with a final ethanol concentration of 5.4 g/L. A mass balance of the whole process integrating protein extraction and cellulosic ethanol production indicated that 1000kg C. Korshinskii Kom leaves will produce 154 kg crude proteins, and the residues will produce 18 kg ethanol.

Abstract: Molecule structures of poly(γ-glutamic acid) (γ-PGA) were modified by ultrasonic, UV and 60Co γ-rays irradiation treatments, which might be used to prepare the polymer with low molecular weight. When 10 g/l γ-PGA solution was sonicated 60 times (400W, working time 3 s and interval 4 s) or that of 20 g/l solution was irradiated from 2 kGy to 10 kGy, the long-chain molecules were broken into smaller fragments. But, as the same solution of 10 g/l was irradiated by UV rays for 10 min, the molecular aggregates were observed in the solution so that the molecular weight distribution of γ-PGA became narrower compared with the control through the analysis of SDS-PAGE. These results would have a reference of the modification of γ-PGA molecules and the production of low molecular weight γ-PGA.

Abstract: Antioxidant activities of acetone and methanol extracts from stems and leaves of Camellia japonica L, one of traditional Chinese medicine consumed in the eastnorth region of China, were examined by a DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical-scavenging assay and a β-carotene-linoleic acid test. In the DPPH system, the antioxidant activity of the acetone extracts was superior to that of the methanol extracts, with IC50 values were 246.56 and 320.17μg/mL, respectively. In the β-carotene-linoleic acid test, the inhibition ratio of the acetone extracts was found to be the higher, compared with the methanol extracts, with IC50 values were 258.19 and 396.88 μg/mL In general, the methanol extract showed greater activity than the acetone extract in both systems, such results might be attributed to the effects of the components of the methanol extract. It was concluded that Camellia japonica L might be a potential natural source of antioxidants.

Abstract: The roles of alfalfa(Lolium multiflorum L ) on remediation of B[a]P contaminated soil，the growth of alfalfa were studied in a pot experiment. The results showed that B[a]P content in soil decreased with culture time during 75d culture period. Alfalfa promotes this decrease. 75 days pot experiment showed that the concentration of B[a]P in soil grown alfalfa was significantly lower than that without plant grown ( P < 0. 05) .Under 1 ,10 and 100mg kg-1 B[a]P treatments, B[a]P biodegradability amounted to 69.5%, 75.2% and 79.1% respectively. While that of soil without plant growth were 47.4%，60.2% and 61.8%, respectively. The activity of soil urease are increasing in soil with plant grown and were obviously higher than those plant growing in uncontaminated soil(p < 0.05), which improved soil degradation ability of soil microbial and plants. There is also inhibition of high contamination on enzyme. Alfalfa makes little contribution to the removal of soil B[a]P. Though soil itself can biodegrade B[a]P, alfalfa could improve bioremediation role of B[a]P contaminated soil. Therefore, increasing alfalfa biomass, enhancing the activity of soil enzymes, creating a good environment condition can enhance the plants ability to remediate B[a]P contaminated soil.

Abstract: In this paper, the antitumor activity in vitro of a series of ionic organotin(IV) complexes synthesized was tested, results of activity of in vitro antitumor for A-549, HCT-8 and Bel-7402 of the compounds were summed up. The results showed that some of these compounds have good anti-tumor activity in vitro.The sdudy of the paper has made useful explorations for the biological activit of metal organic compound.

Abstract: To investigate the efficacy of the compound preparation named KZY-2 which include the effective group formula of anemarrhena asphodeloides bunge and rhizoma coptidis on the fluconazole and ifraconazo resistant strains of Candida albicans respectively in vitro. The fluconazole and ifraconazo resistant strains of Candida albicans were sieved by drug sensitive scrip test and the diameter of inhibition zone was measured adopting the method of agar plate diffusion, reference to the M27-A recommended by the United States National Laboratory Standards Committee (NCCLS), the minimal inhibitive concentration(MIC,mg/m1) of KZY-2 against the the standard strain(ATCC32354) and the fluconazole and ifraconazo resistant strains of candida albicans was measured respectively. Results showed that the 12 fluconazole and ifraconazo resistant strains which named RC1 to RC12 were sieved from the 20 strains Candida albicans isolated from clinic, the diameters of inhibited zone of KZY-2 against ATCC32354 was 32mm and against RC1～RC12 was between 12mm and 28mm, the MIC of KZY-2 against ATCC32354 was 312.5μg/m1 and against RC1～RC12 was between 625μg /m1 and 5000μg /m1. These results indicate that KZY-2 has good antifungi efficacy on the standard strain and the fluconazole and ifraconazo resistant strains of Candida albicans in vitro.