Analysis of iron- and sulfur-oxidizing bacteria in a treatment plant of acid rock drainage from a Japanese pyrite mine by use of ribulose-1, 5-bisphosphate carboxylase/oxygenase large-subunit gene

Iron- and sulfur-oxidizing bacteria in a treatment plant of acid rock drainage (ARD) from a pyrite mine in Yanahara, Okayama prefecture, Japan, were analyzed using the gene (cbbL) encoding the large subunit of ribulose-1, 5-bisphosphate carboxylase/oxygenase (RubisCO). Analyses of partial sequences of cbbL genes from Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Acidithiobacillus caldus strains revealed the diversity in their cbbL gene sequences. In contrast to the presence of two copies of form I cbbL genes (cbbL1 and cbbL2) in A. ferrooxidans genome, A. thiooxidans and A. caldus had a single copy of form I cbbL gene in their genomes. A phylogenetic analysis based on deduced amino acid sequences from cbbL genes detected in the ARD treatment plant and their close relatives revealed that 89% of the total clones were affiliated with A. ferrooxidans. Clones loosely affiliated with the cbbL from A. thiooxidans NB1-3 or Thiobacillus denitrificans was also detected in the treatment plant. cbbL gene sequences of iron- or sulfur-oxidizing bacteria isolated from the ARD and the ARD treatment plant were not detected in the cbbL libraries from the treatment plant, suggesting the low frequencies of isolates in the samples.     

Production of Lipase from Candida rugosa Using Cheese Whey through Experimental Design and Surface Response Methodology

The present work investigates the production of lipases from Candida rugosa in a culture medium containing cheese whey and also determines the importance of the components of the used culture medium using two experimental design and surface response methodology. When pure cheese whey was used as culture medium, the lipolytic activity measured in the broth, after 120 h of fermentation, was 5.18 U/mL. From the first experimental design, it was possible to conclude that the combination of brewery co-product, yeast and malt extract, Tween 80, and olive oil with cheese whey provided an average increase of 15 U/mL in the enzymatic activity, which represented 287.5% in relation to the activity obtained using only with cheese whey as substrate. Nevertheless, this essay did not provide a predictive model for the lipase production using the studied components. From the second experimental design, with suppression of yeast and malt extract, the best values of enzymatic activity were, on average, 28% lesser than the observed in the first optimization, but yet 180% higher than the obtained values when only cheese whey was present as substrate. A second-order model correlating the used components could be achieved, indicating that high concentrations of brewery co-product and Tween 80 enhanced the production of C. rugosa lipases in a medium incorporating cheese whey, which, at high concentrations, can substitute olive oil that may have its concentration diminished in this condition.     

Formation of ethyl carbamate in umeshu (plum liqueur)

Samples of umeshu, a Japanese plum liqueur made from unripe plums, shochu and crystal sugar, were stored under fluorescent light, in the dark and in the refrigerator. The amount of ethyl carbamate formed in umeshu exposed to light or room temperature was larger than that in the dark or at low temperature. The amount of ethyl carbamate formed in umeshu to which cyanide had been added was larger than that in the absence of added cyanide. Thus, the amount of ethyl carbamate formed in the umeshu was increased by not only light and higher temperature, but also cyanide. Samples of model alcoholic beverages were stored under various conditions using red, yellow and blue cellophanes. The amount of ethyl carbamate formed in the model alcoholic beverage with blue cellophane was larger than in the cases of red and yellow cellophanes. It was found that the amount of ethyl carbamate formed in the model alcoholic beverage was increased by light in the wavelength range of 375-475 nm.     

Structural enhanced information and its application to improved visualization of self-organizing maps

In this paper, we propose structural enhanced information for detecting and visualizing main features in input patterns. We have so far proposed information enhancement for feature detection, where, if we want to focus upon components such as units and connection weights and interpret the functions of the components, we have only to enhance competitive units with the components. Though this information enhancement has given favorable results in feature detection, we further refine the information enhancement and propose structural enhanced information. In structural enhanced information, three types of enhanced information can be differentiated, that is, first-, second- and third-order enhanced information. The first-order information is related to the enhancement of competitive units themselves in a competitive network, and the second-order information is dependent upon the enhancement of competitive units with input patterns. Then, the third-order information is obtained by subtracting the effect of the first-order information from the second-order information. Thus, the third-order information more explicitly represents information on input patterns. With this structural enhanced information, we can estimate more detailed features in input patterns. For demonstrating explicitly and intuitively the improved performance of our method, the conventional SOM was used, and we transformed competitive unit outputs so as to improve visualization. The method was applied to the well-known Iris problem, an OECD countries classification problem and the Johns Hopkins University Ionosphere database. In all these problems, we succeeded in visualizing the detailed and important features of input patterns by using the third-order information.     

Optimization of power‐efficient wireless mesh networks in outdoor and indoor environments in Japan

This paper proposes the optimization of power‐efficient wireless mesh networks in outdoor and indoor environments, particularly for gas metering in Japan. We investigate the effect on total power consumption by changing the output power and allocated frequency band of a gas metering system. From the simulation results, we show that these changes are effective in achieving low power consumption. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

A STUDY OF BEER STALING USING CHEMILUNINESCENCE ANALYSIS

The chemiluninescence (CL) analysis has been used to study beer staling. Several types of commercial Japanese beers were stored at 37°C and their CL development analysed at 60°C. The CL level in beer developed as the beer was stored to reach a maximum level and then decreased. The sum of the CL intensities for the first 1 hour showed a good relationship with staling degree as assessed in mean panel scores. It is postulated that the deterioration rates of beers might be assessed from the CL producing patterns in the fresh beers before storage. The presence of sulfite in beer depressed the CL production during its storage indicating that there is some contribution of sulfite to flavour stability due to its inhibitory effect on radical reactions in beer.     

Antimicrobial and antioxidant activities of carvacrol microencapsulated in hydroxypropyl-beta-cyclodextrin

Carvacrol is a hydrophobic compound that exhibits high antimicrobial and antioxidant activities. Cyclodextrins are used to increase solubility and dissolution through water-insoluble compounds inclusion into their hydrophobic cavities. Hence, this study aimed to characterize carvacrol inclusion complexes with hydroxypropyl-beta-cyclodextrin (HPBCD) by establishing the physico-chemical properties and evaluate their antimicrobial and antioxidant properties. Inclusion complexes were prepared by kneading (KN) and freeze-drying (FD) methods. Entrapment efficiency was 78.09 ± 1.24% for KN, and 83.74 ± 1.15% for FD. Polydispersity index was greater than 0.2 for both methods. Particle size for KN and FD were 0.360 ± 0.003 and 0.377 ± 0.007 μm, respectively. Carvacrol–HPBCD antimicrobial activity was higher (P < 0.05) than for free carvacrol for both bacteria, Escherichia coli K12 and Salmonella enterica serovar Typhimurium LT2, indicating that HPBCD increased water solubility and consequently increased contact between carvacrol and bacteria in medium. Antioxidant activity was lower (P < 0.05) for inclusion complexes indicating HPBCD makes carvacrol less available to react with free radical. The stability study indicated that light did not affect (P > 0.05) degradation, indicating that the microparticles were stable throughout storage. Therefore, carvacrol–HPBCD complexes may have important applications in the food industry as stable antimicrobial systems.     

Existence of a tungsten-binding protein in Acidithiobacillus ferrooxidans AP19-3

A tungsten-binding protein was purified from a plasma membrane preparation of the iron-oxidizing bacterium, Acidithiobacillus ferrooxidans AP19-3 in an electrophoretically homogenous state. The protein was composed of two subunits with apparent molecular masses of 12 and 20.7 kDa. The molecular mass of the native protein was estimated to be 26.4 kDa in the presence of 1.5% 1-o-octyl-D -glucopyranoside (OGL), indicating that the native tungsten-binding protein is a heterodimeric protein. The amounts of tungsten bound to 1 mg of plasma membranes of A. ferrooxidans AP19-3 and the purified tungsten-binding protein at pH 3.0 were 191 and 1506 mug, respectively. In contrast, the amounts of tungsten bound to 1 mg of albumin, aldolase, catalase, chymotrypsinogen A, ferritin, and ferredoxin at pH 3.0 were 13.1, 18.6, 12.8, 16.6, 11.4, and 6.1 mug, respectively. Incubation of the tungsten-binding protein for 1 h with 10 mM Na(2)WO(4) plus 10 mM metal ion, such as NaVO(3), Na(2)MoO(4), CuSO(4), NiSO(4), MnSO(4), CoSO(4), or CdCl(2), did not markedly affect the amount of tungsten bound to the tungsten-binding protein, suggesting that the protein specifically binds tungsten.     

Effect of thrombopoietin on proliferation of blasts from CD7-positive acute myelogenous leukaemia

We investigated the effect of thrombopoietin (TPO) on the growth of leukaemic blasts from 30 acute myelogenous leukaemia (AML) patients according to the surface expression of CD7 and CD34: 10 patients were CD7 positive (CD7+), nine were CD7 negative/CD34+ (CD7-/CD34+) and the remaining 11 were CD7-/CD34-. Significant growth response of leukaemic blasts to TPO was observed in 10/10 CD7+, 5/9 CD7-/CD34+ and 2/11 CD7-/CD34- AML cases using 3H-thymidine incorporation. Synergistic stimulatory effects of TPO with stem cell factor (SCF), interleukin-3 (IL-3), granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor were observed in both TPO-responding cases (9/17) and TPO-non-responding cases (8/13). In a leukaemic blast colony assay. significant growth response to TPO was observed in 5/6 CD7+ and 4/17 CD7-AML cases examined. However, the effect of TPO on the growth of CD7+ leukaemic blasts was not so potent as that of IL-3 and SCF, both of which support the proliferation of primitive haemopoietic progenitors. Expression of c-mpl (TPO receptor) was significantly higher in CD7+ AML cases than in CD7- cases, suggesting a relationship between expression of c-mpl and proliferative response to TPO. These data indicate that CD7+ leukaemic blasts express functional TPO receptors and proliferate in response to TPO. These observations also imply that CD7 expression on AML blasts may indicate involvement of leukaemic progenitors at an early stage of multipotent haemopoietic stem cells.