• Journal of Microbiology and Biotechnology
• /
• v.34 no.5
• /
• pp.1040-1050
• /
• 2024

To isolate and analyze bacteria with Verticillium wilt-resistant properties from the fermentation residue of kitchen wastes, as well as explore their potential for new applications of the residue. A total of six bacterial strains exhibiting Verticillium wilt-resistant capabilities were isolated from the biogas residue of kitchen waste fermentation. Using a polyphasic approach, strain ZL6, which displayed the highest antagonistic activity against cotton Verticillium wilt, was identified as belonging to the Pseudomonas aeruginosa. Bioassay results demonstrated that this strain possessed robust antagonistic abilities, effectively inhibiting V. dahliae spore germination and mycelial growth. Furthermore, P. aeruginosa ZL6 exhibited high temperature resistance (42℃), nitrogen fixation, and phosphorus removal activities. Pot experiments revealed that P. aeruginosa ZL6 fermentation broth treatment achieved a 47.72% biological control effect compared to the control group. Through activity tracking and protein mass spectrometry identification, a neutral metalloproteinase (Nml) was hypothesized as the main virulence factor. The mutant strain ZL6ߡNml exhibited a significant reduction in its ability to inhibit cotton Verticillium wilt compared to the strain P. aeruginosa ZL6. While the inhibitory activities could be partially restored by a complementation of nml gene in the mutant strain ZL6CMߡNml. This research provides a theoretical foundation for the future development and application of biogas residue as biocontrol agents against Verticillium wilt and as biological preservatives for agricultural products. Additionally, this study presents a novel approach for mitigating the substantial amount of biogas residue generated from kitchen waste fermentation.

• The Korean journal of internal medicine
• /
• v.39 no.3
• /
• pp.399-412
• /
• 2024

Antimicrobial stewardship programs (ASPs) can lower antibiotic use, decrease medical expenses, prevent the emergence of resistant bacteria, and enhance treatment for infectious diseases. This study summarizes the stepwise implementation and effects of ASPs in a single university-affiliated tertiary care hospital in Korea; it also presents future directions and challenges in resource-limited settings. At the study hospital, the core elements of the ASP such as leadership commitment, accountability, and operating system were established in 2000, then strengthened by the formation of the Antimicrobial Stewardship (AMS) Team in 2018. The actions of ASPs entail key components including a computerized restrictive antibiotic prescription system, prospective audit, post-prescription review through quantitative and qualitative intervention, and pharmacy-based interventions to optimize antibiotic usage. The AMS Team regularly tracked antibiotic use, the effects of interventions, and the resistance patterns of pathogens in the hospital. The reporting system was enhanced and standardized by participation in the Korea National Antimicrobial Use Analysis System, and educational efforts are ongoing. Stepwise implementation of the ASP and the efforts of the AMS Team have led to a substantial reduction in the overall consumption of antibiotics, particularly regarding injectables, and optimization of antibiotic use. Our experience highlights the importance of leadership, accountability, institution-specific interventions, and the AMS Team.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.6
• /
• pp.665-672
• /
• 2013

This study was conducted to evaluate the effects of a chelating agent on cucumber growth and changes in soil nutrients availability in polytunnel greenhouse fields. Diethylene triamine penta acetic acid (DTPA) was selected as a chelating agent. Two experiments were carried out as follows: i) For field experiment in the autumn season of 2010, each plot was treated by varying the concentration and the number of times being applied with DTPA; [DTPA (0.5 mM, 1 time/3 months), DTPA (0.06 mM, 1 time/1 week), DTPA (0.13 mM, 1 time/2 weeks), DTPA (0.06 mM, 1 time/1 week)+N]. Conventional practice was also investigated. ii) In the spring and summer seasons of 2011, each plot was treated by varying the concentration (0, 0.06, 0.13, 0.19 mM) of DTPA, chemical fertilizers (NPK), and combination of chemical fertilizers and DTPA 0.06 mM. The fruit yields of cucumber and soil chemical properties had no significant differences between treatments. However, in the spring season of 2011, DTPA 0.06 mM plot added 1 time per 2 weeks increased the yield of cucumber, but caused the reduction of yield in next cultivation season. This result showed that excess use of DTPA can cause the damage of crop growth. The inorgainc contents such as Ca and Mg absorbed by cucumber plant had significant differences between DTPA 0.19 mM (2 times/1 week) and fertilizers plus DTPA treatments [DTPA 0.06 mM (2 times/1 week) + 1/2 NPK, DTPA 0.06 mM (2 times/1 week) + NPK]. The input cost of fertilizers was saved when the concentration and the number of times added with DTPA was 0.06 mM and 1 time a week, respectively. This treatment used 67% less of applied fertilizers cost than the plot of conventional practice did. Thus, this research suggested that the application of DTPA 0.06 mM by 1 time a week can be effective for sustainability of crop production and reduction of fertilizers usage in polytunnel greenhouse.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.10
• /
• pp.1715-1719
• /
• 2004

In order to help the preservation of the unshiu orange and pear, antimicrobial paper incorporating grapefruit seed extract and zeolite was applied to pack fruits. Unshiu orange was packed in a box (24${\times}$24${\times}$22 cm) attached with antimicrobial paper and then stored respectively at l$0^{\circ}C$. Pears were wrapped individually before storage at l$0^{\circ}C$. During the storage, weight loss, pH, total acidity, soluble solid content, microbial load and decay were measured as quality indices. Steady pH increase in unshiu orange was observed to slightly decrease total acidity during the storage with little difference between the packaging treatments. The microbial loads of total aerobic bacteria, and yeast/mold counts were suppressed during storage by the antimicrobial paper packaging, which also contributed to reducing the decayed unshiu orange. Limited reduction of total aerobic bacteria and yeast/mold counts was observed only for initial storage period for the pears wrapped with 9 and 12% antimicrobial agent-added papers. Antimicrobial paper was useful for the reduction of microbial load in unshiu orange and pear without other quality deterioration.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.20 no.5
• /
• pp.452-460
• /
• 2008

Anti-foaming agents and foam fences have been used to remove the foam at the outfall of power plants, but there are some problems as consumption of maintenance costs and insufficiency of effect. Therefore, development of the methods how to remove the foam by stable coastal structure has been required. In this study, numerical simulation of air entrainment was carried out to design the submerged outlet structure for reducing foam using curtain walls. The air entrainment rate and the discharge of entrained air change according to the shape of weir and curtain wall. Hence, it is necessary to design the optimum section through comparison of each case. The optimum section which has the maximum rate of foam reduction was determined by the simulation results. In addition, it was found that the flow velocity at the submerged outlet is to be smaller than 1 m/s and the submerged depth of curtain wall is to be taller than height of the submerged outlet section.

• Journal of Korean Society of Environmental Engineers
• /
• v.28 no.2
• /
• pp.191-196
• /
• 2006

The injection of ozone, produced by dielectric barrier discharge, into the exhaust gas gives rise to a rapid oxidation of NO that is the main component of nitrogen oxides($NO_x$) in most practical exhaust gases. Once NO is converted into $NO_2$, it on readily be reduced to $N_2$ in the next step by a reducing agent such as sodium sulfide and sodium sulfite. The reducing agents used ca also remove $SO_2$ effectively, which makes it possible to treat $NO_x\;and\;SO_2$ simultaneously. The present two-step process made up of an ozonizing chamber and an absorber containing a reducing agent solution was able to remove about 95% of the $NO_x$ and 100% of the $SO_2$, initially contained in the simulated exhaust gas. The formation of $H_2S$ from sodium sulfide was prevented by using a strong basic reagent(NaOH) together with the reducing agent. The removal of $NO_x$\;and\;SO_2$ was more effective for $Na_2S$ than $Na_2SO_3$.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.28 no.2
• /
• pp.15-29
• /
• 2020

The aims of this study is to improve physical properties of the sewage sludge and the process sludge generated in the leachate treatment by mixing the dry fuel, to develop the neutral solidifing agents that reduce oder, and to recycle the sewage and the process sludges as landfill cover materials. The mixing ratio (W/W) of sludges and dry fuel was appropriate at about 1:1, and the mixed materials were shown to be homogeneous at that ratio. We could know that when the sludges were mixed with dry fuel, moisture contents and viscosities are reduced, and air passages are formed between particles and particles. The various mixing tests and odor tests showed that the neutral solidifing agent was effective for the odor reduction. The main ingredient of the solidifing agent is the ash of sewage sludge, enabling it competitive in waste recycling and production costs. The landfill cover, using developed neutral solidification agent, improved physical properties to satisfy the quality standards and to increase the compressive strength. It also proved to reduce the value of complex oder and the usage of solidification agent to 1/3 (3,000 to 1,000) and to 1/8 (50% to 6%), respectively, from the comparative study with alkaline solidified landfill cover. Further research is under way to prove that this can be mixed with general soil to be used as a soil improvement agent for plant cultivation.

• Journal of Distribution Science
• /
• v.10 no.10
• /
• pp.25-33
• /
• 2012

Purpose - The Garak agricultural wholesale market ('Garak Market') plays a central role in the distribution of agricultural products in Korea and is important in connecting consumers with producers. However, problems regarding inefficiencies and the high-cost structure of the wholesale market's distribution/logistical system are being raised in relation to severe competition among retailers. Furthermore, the service needs of retailers and market users are not being fulfilled due to the inconsistency of the wholesale market's functions and facilities, thus reducing the competitiveness of the market. In this regard, innovative changes are being requested of the agricultural wholesale market according to changes in the agricultural product distribution environment. In particular, the lack of unloading facilities and the outdated unloading system of the wholesale market must be improved to enhance system efficiency. Research design, data, and methodology - This study observed the problems of the unloading system of the agricultural wholesale market in order to present relevant measures for improvement. The need for unloading auctions was also researched in this study. The survey of 70 forwarders belonging to the producing district distributor association of the Garak market was conducted by post. Additionally, 20 auction dealers and 59 shippers and transporters were individually interviewed. The survey on the need for unloading auctions used five-point Likert Scales. The statistical analysis was conducted with SPSS WIN 12.0 software. Results - First, the wholesale market must employ members of the unloading labor union to allow these employees to directly manage the unloading process. Second, it is crucial to revise regulations to ensure that the principal agent pays the unloading cost according to the standard unloading cost system. Third, the vehicle auction carried out for certain vegetable products must be converted to the unloaded auction system. According to the related interviews with the wholesale market's distribution agents, whereas shippers and transporters recognized the need for unloaded auctions, auction dealers tend to have a negative view of this system. Furthermore, the stated reasons in favor of unloaded cabbage, radish, and other vegetable auctions were prevention of constraint, creation of transparent trade conditions, and reduction of corrected seller tickets. Many of the respondents answered that the transport cost reduction rate in unloaded auctions must be below 20%. Fourth, the unloading system must be mechanized and a detailed, reasonable plan must be provided to settle the existing conflict with the unloading labor union. Conclusions - The proposals in this study are expected to play an important role in improving the cargo handling system of the wholesale agricultural product market in the future. Improving the system is expected to help shore up the competitiveness of the industry. If all the related bodies closely cooperate with each other and work harder, taking advantage of the synergies created by the facility modernization project, the Garak market will play a pivotal role in the distribution of agricultural products.

• Journal of Korean Society of Environmental Engineers
• /
• v.27 no.3
• /
• pp.286-292
• /
• 2005

This study is to investigate the industrial boiler which can be significantly affected by the restriction of NOx. Note that the application of SNCR method to industrial boiler is usually blown as not feasible due to the insufficient residence time for proper mixing. The purpose of this study is to investigate the applicability of the SNCR system application to the industrial boiler, which produces 40 tons of steam per hour using heavy oil. For the industrial boiler with 3-D rectangular coordinate, the general coding are made fur various turbulence modeling such as turbulent flow, turbulent fuel combustion, thermal NO formation and destruction together with the NO reaction with reducing agents. Further, the incorporation of drop trajectory model is successfully made in 3-D rectangular coordinate with Lagrangian frame and the main swirl burner effect on the characteristics of flame is considered. As expected a short flame was created and thereby NOx is removed more efficiently by increasing the proper region of temperature for NO reduction reaction. The validation of program was made successfully by the comparison of experimental data. Based on the reliable calculation results, the SNCR method in a industrial boiler shows the possibility as one of viable NO reduction method by the use of well designed mixing air of reducing agent.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.14
• /
• pp.5635-5641
• /
• 2015

Background: Cirrhosis is regarded as a possible end stage of many liver diseases, including viral infection. It occurs when healthy liver tissue becomes damaged and is replaced by scar tissue and finally may lead to hepatocellular carcinoma. Interferons (IFNs)are two general categories, type I and II. Type I includes one beta interferon and over 20 different alpha interferons. Alpha interferons are very similar in how they work, interacting with other proteins on cells like receptors. The main objective of this study was to compare Mx gene productivity post different cell line treatment with imported and Egyptian biosimilar locally produced IFNs, as well as the efficacy of those tested IFNs. Also, an assessment was made of sensitivity of different cell lines as alternatives to that recommended for evaluation of antiviral activity. Materials and Methods: Different cell lines (Vero, MDBK and Wish) were employed to evaluate cytotoxicity using the MTT assay. Antiviral activity was evaluated compared with standard IFN against VSV, Indiana strain -156, on tested rh-IFNs (imported; innovated and Egyptian biosimilar locally produced IFNs) in the pre-treated cell lines previously mentioned. The virus was propagated in the Wish cell line as recommended. Finally we estimated up-regulation of the Mx gene as a biomarker. Results: Data recorded revealed that test IFNs were safe in test cell lines. Viability was around 100%. Locally tested interferon did not realize the international potency limits, while the imported one was accepted compared with the standard IFN. These results were the same either using infectivity titer reduction assay or crystal violet staining of residual non- infected cells. Mx protein production was cell type related and confirmed by the detected Mx gene expressed in imported and locally produced IFN pre-treated cell lines. The expression of the gene was arranged in the order of Vero> wish > MDBK for the imported IFN, while for the Egyptian biosimillar locally produced one it was MDBK> Vero> wish. With regard to the antiviral activity there was a significant difference of imported IFN potency compared with the locally produced IFN (P<0.05), the IFN potential (antiviral activity) was not cell line related and showed non-significant difference for each separate product. Conclusions: Vero cells can be used as an alternative cell line for evaluation of IFN potency in case of unavailable USP recommended cell lines. Alternative potency evaluation assay could be used and proved significant difference in IFN potency in case of local and imported agents. Evaluation of antiviral activity could be used in parallel to viral infectivity reduction assay for better accuracy. Mx gene can be used as a marker for IFN potential.