• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.165-166
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• 2004

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.58-65
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• 2011

The bacterial uranium(VI) reduction and its resultant low solubility make this process an attractive option for removing U from groundwater. An impact of aqueous suspending iron phase, which is redox sensitive and ubiquitous in subsurface groundwater, on the U(VI) bioreduction by Shewanella putrefaciens CN32 was investigated. In our batch experiment, the U(VI) concentration ($5{\times}10^5M$) gradually decreased to a non-detectable level during the microbial respiration. However, when Fe(III) phase was suspended in solution, bioreduction of U(VI) was significantly suppressed due to a preferred reduction of Fe(III) instead of U(VI). This shows that the suspending amorphous Fe(III) phase can be a strong inhibitor to the U(VI) bioreduction. On the contrary, when iron was present as a soluble Fe(II) in the solution, the U(VI) removal was largely enhanced. The microbially-catalyzed U(VI) reduction resulted in an accumulation of solid-type U particles in and around the cells. Electron elemental investigations for the precipitates show that some background cations such as Ca and P were favorably coprecipitated with U. This implies that aqueous U tends to be stabilized by complexing with Ca or P ions, which easily diffuse and coprecipitate with U in and around the microbial cell.

• Food Engineering Progress
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• v.22 no.4
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• pp.386-391
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• 2018

Effects of a commercial scale intervention system combining ultraviolet (UV)-C and plasma treatments on the microbial decontamination of black pepper powder were investigated. The process parameters include treatment time, time for plasma accumulation before treatment, and water activity of black pepper powder. A significant reduction in the number of indigenous aerobic mesophilic bacteria in black pepper powder was observed after treatments lasted for ${\geq}20min$ (p<0.05) and the reduction was differed by powder manufacturer. The microbial reduction rates obtained by individual UV-C treatment, individual plasma treatment, and UV-C/plasma-combined treatment were 0.2, 0.5, and 1.0 log CFU/g, respectively, suggesting that the efficacy of the microbial inactivation was enhanced by treatment combination. Nonetheless, neither plasma accumulation time nor powder water activity affected the microbial inactivation efficacy of the combined treatment. The UV-C/plasma-combined treatment, however, decreased lightness of black pepper powder, and the decrease generally increased as operation time increased. The plasma accumulation time of 20 min resulted in significant reduction in both lightness and brown color. The results indicate that the commercial-scale intervention system combining treatments of UV-C and plasma has the potential to be applied in the food industry for decontaminating black pepper powder.

• Journal of Microbiology and Biotechnology
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• v.21 no.2
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• pp.187-191
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• 2011

Microbial fuel cells (MFCs) were successfully enriched using sludge contaminated with Cr(VI) and their characteristics were investigated. After enrichment, the charge of the final 10 peaks was 0.51 C ${\pm}$ 1.16%, and the anodic electrode was found to be covered with a biofilm. The enriched MFCs removed 93% of 5 mg/l Cr(VI) and 61% of 25 mg/l Cr(VI). 16S rDNA DGGE profiles from the anodic electrode indicated that ${\beta}$-Proteobacteria, Actinobacteria, and Acinetobacter sp. dominated. This study is the first to report that electrochemically active and Cr(VI)-reducing bacteria could be enriched in the anode compartment of MFCs using Cr(VI)-containing sludge and demonstrates the Cr(VI) removal capability of such MFCs.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.124-135
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• 2003

In order to prevent pollution from animal waste, the excretion of nutrients should be reduced through proper nutritional management. Among the many nutrients of concern, such as N, P, Cu, Zn and K, P is one of the most concerned nutrients to be managed. Seven feeding trials, three with layers and four with broilers, were conducted to determine if microbial phytase supplementation can reduce non-phytate phosphorus (NPP) level in diets and results in concomitant reductions of P excretion. The results showed that microbial phytase can be successfully used to achieve these purposes. Activity of natural phytase in certain plant feedstuffs is high enough to be considered in feed formulation. Three experiments have been conducted to study the characteristics of plant phytase and its application to feeding of broilers. Selected brands of wheat bran could be successfully used as a source of phytase in broiler feeding.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.16 no.1
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• pp.5-7
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• 2010

Two kinds of polymer coating (acrylic polymer and vinyl acetate ethylene copolymer) added with 5% nisin were fabricated on the paperboards and tested in their antimicrobial activity against Micrococcus flavus ATCC 10240 inoculated into water contacting the coating at $10^{\circ}C$. Vinyl acetate ethylene copolymer giving faster and higher nisin migration presented the greater reduction in the microbial count than the other coating, which endorsed that the migrated nisin is mainly responsible for the microbial inhibition or destruction. There was also a slight effect of the coating polymer itself in the microbial inhibition.

• Environmental Engineering Research
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• v.22 no.2
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• pp.157-161
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• 2017

Simultaneous treatment of food waste leachate and power generation was investigated in an air-cathode microbial fuel cell. A TCOD removal efficiency of $95.4{\pm}0.3%$ was achieved for an initial COD concentration of 2,860 mg/L. Maximum power density ranged was maximized at $1.86W/m^3$, when COD concentration varied between 60 mg/L and 2,860 mg/L. Meanwhile, columbic efficiency was determined between 1.76% and 11.07% for different COD concentrations. Cyclic voltammetric data revealed that the oxidation peak voltage occurred at -0.20 V, shifted to about -0.25 V. Moreover, a reduction peak voltage at -0.45 V appeared when organic matters were exhausted, indicating that reducible matters were produced during the decomposition of organic matters. The results showed that it was feasible to use food waste leachate as a fuel for power generation in a microbial fuel cell, and the treatment efficiency of the wastewater was satisfied.

• Preventive Nutrition and Food Science
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• v.6 no.4
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• pp.240-243
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• 2001

Fresh pasta was packaged in a modified atmosphere of 22% $CO_2$/78% $N_2$ and compared with a control air package for its quality changes during storage at 8$^{\circ}C$. The modified atmosphere packaging suppressed the microbial growth of total aerobic bacteria and yeasts/molds with a concomitant reduction in the rates of physical and chemical quality changes, and thus successfully extended the shelf life of fresh packs from 20 days of air packs to 40 days based on microbial criterion of 10$^{6}$ cfu/g. The shelf life extension was greater when the initial microbial quality of the product was better.

• Plant Resources
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• v.3 no.1
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• pp.59-65
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• 2000

The opening process of cut calla flower was faster at 30 t than at lower temperatures as it could be expected from its tropical origin. Gibberellin enhanced the flower opening, however, it also speeded up senescent. Silver thiosulfate was effective in prolonging the vase life of the cut calla flower. Silver thiosulfate reduced ethylene generation by the flower and inhibited microbial growth in the flower stalk. Reduction in ethylene generation and inhibition of microbial growth is thought to be responsible for the extension of the vase life of cut calla flowers by silver thiosulfate.

• Environmental Engineering Research
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• v.13 no.2
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• pp.51-65
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• 2008

The increasing demand for energy in the near future has created strong motivation for environmentally clean alternative energy resources. Microbial fuel cells (MFCs) have opened up new ways of utilizing renewable energy sources. MFCs are devices that convert the chemical energy in the organic compounds to electrical energy through microbial catalysis at the anode under anaerobic conditions, and the reduction of a terminal electron acceptor, most preferentially oxygen, at the cathode. Due to the rapid advances in MFC-based technology over the last decade, the currently achievable MFC power production has increased by several orders of magnitude, and niche applications have been extended into a variety of areas. Newly emerging concepts with alternative materials for electrodes and catalysts as well as innovative designs have made MFCs promising technologies. Aerobic bacteria can also be used as cathode catalysts. This is an encouraging finding because not only biofouling on the cathode is unavoidable in the prolonged-run MFCs but also noble catalysts can be substituted with aerobic bacteria. This article discusses some of the recent advances in MFCs with an emphasis on the performance, materials, microbial community structures and applications beyond electricity generation.