• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.594-601
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• 2010

Azotobacter chroococcum H23 (CECT 4435), Azotobacter vinelandii UWD, and Azotobacter vinelandii (ATCC 12837), members of the family Pseudomonadaceae, were used to evaluate their capacity to grow and accumulate polyhydroxyalkanoates (PHAs) using two-phase olive mill wastewater (TPOMW, alpeorujo) diluted at different concentrations as the sole carbon source. The PHAs amounts (g/l) increased clearly when the TPOMW samples were previously digested under anaerobic conditions. The MNR analysis demonstrated that the bacterial strains formed only homopolymers containing $\beta$-hydroxybutyrate, either when grown in diluted TPOMW medium or diluted anaerobically digested TPOMW medium. COD values of the diluted anaerobically digested waste were measured before and after the aerobic PHA-storing phase, and a clear reduction (72%) was recorded after 72 h of incubation. The results obtained in this study suggest the perspectives for using these bacterial strains to produce PHAs from TPOMW, and in parallel, contribute efficiently to the bioremediation of this waste. This fact seems essential if bioplastics are to become competitive products.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.127-133
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• 2001

It can be known that from leachate generated in the initial stage of landfill there are a lot of undecomposed orgainc materials, its sulfur component reduces to sulfide ion by sulfur reducing microorgarnisms as an anaerobic digestion proceeds, the sulfide ion makes the leachate discolor to black by forming metal sulfide sol, on condition that much more equivalent of sulfide ion than that of metal ion is present, and the metal sulfide sol can be generated to the precipitates by forming black-colored particulates. Therefore, we can confirm the important possibility for the economic and efficient treatment of leachate that it can be passivated, provided that much more equivalent of sulfide ion is present in the reaction of sulfide ion and metal ion.

• Journal of Korean Society on Water Environment
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• v.25 no.6
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• pp.872-878
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• 2009

Advanced Phase Isolation Ditch (APID) process was studied to develop economic retrofitting technology, for the plants where retrofitting of common activated sludge process is required. In this study, to develop and apply the modified intermittently aeration mode as process control conditions for treating municipal wastewater, a demonstration plant was installed and operated in the existing sewage treatment plant of P city. During this study, the average effluent $BOD_5$, SS, T-N, and T-P concentrations were 6.3, 4.5, 10.0, and 1.3 mg/L. The modified mode decreased the nitrification capability more than the conventional mode in the application period. Nitrate in the anaerobic condition can have a negative effect on biological phosphorus removal. In the decreasing nitrate levels, the modified mode increased the biological ability of removal phosphorus more than the conventional mode in this study. Therefore, newly developed APID process with modified intermittent aeration mode can be one of the useful processes for stable organic matter and nutrients removal.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.417-430
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• 2009

A BNR comprehensive performance evaluation (BNR CPE) system was established employing system-oriented evaluation methodology for biological nutrient removal (BNR) processes based on the CPE techniques developed by U.S. EPA for evaluation of conventional biological processes. The BNR CPE system applied to five domestic BNR plants adopting $A^2/O$ process confirmed that all target plants except the smallest one had not any serious defective performance and process stability was enhanced with increasing plant size. The system also clearly verified relatively poor performances in anoxic reactors without exception mainly due to influent carbon limit rather than functional defect. Consistent good performances were confirmed even during both winter season and wet weather generally known to be difficult to achieve satisfactory removals. Presentation of evaluation results by modified radar chart system simplified and clarified the evaluation and analysis procedures. The BNR CPE system could not only discover readily the causes of present and prospective poor performances but also facilitate the suggestion of their optimization options. Mutual effect and cause-and-effect among operation parameters and unit processes were also found easily using the evaluation system. The system justified that the adverse effect of defective operating parameters could be compensated by other favorable parameters, especially in anaerobic and anoxic reactors as well as during the winter season.

• Water for future
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• v.22 no.1
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• pp.117-125
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• 1989

This study deals with the performance of an acivated sludge system which is modified by the researcher to function without any additional chemical or internal recyle in removing organics, nitrogen, and phosphorus from synthetic wastewater. To improve the nutrient removal efficiency, the researcher utilized the anoxic, anaerobic, and aerobic reactor sequences with a single sludge return, whiched to nitrification/denitrification and phosphorus release/overplus accumulation. A bench scale system was operated with a view to investigating the reaction characteristics of each reactor, and to measuring the biological kinetic coefficients(Y, $K_d$, k, $K_s$) for theremoval of COD in relation to the mean cell residence time at five different MLSS concentrations, 5000, 4200, 3300, 2600, and 1900 mg/l. The results of the research showed that organic substance and nutrient were removed simultaneously by this modified activated sludge process. And the process kad 66%-99% ortho-p removal efficiency.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.567-578
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• 2013

A microbial fuel cell (MFC) is a bio-electrochemical device that converts chemical energy in the chemical bonds in organic compounds to electrical energy through catalytic reactions of microorganisms under anaerobic conditions. Power density and Coulombic efficiency are significantly affected by the types of microbe in the anodic chamber of an MFC, configurations of the system and operating conditions. The achievable power output from MFC increased remarkably by modifying their designs such as the optimization of MFC configurations, the physical and chemical operating conditions, and the choice of biocatalysts. This article presents a critical review on the recent advances made in MFC research with the emphasis on MFC configurations, optimization of important operating parameters, performances and future applications of MFC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.279-286
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• 1994

Anthocyanins were isolated and identified from grape peels which were wasted much in Korea, and their characteristics were as follows .Isolated pigments from grape peels were 11 varieties such as 5 varieties of 3, 5-diglucoside (DG), 6 varieties of 3-monoglucoside (MG), and acylated pigment was 2 varieties of them. Malvidin was 4 varieties , petunidin , peonidin and delphinidin 2 varieties in each, and cyanidin 1 variety of 11 vareities. Malvidin -3, 5-diglucoside and peonidin -3, 5-diglucoside of anthocyanins were above 48% in total anthocyanins content of 114.99mg/g in dried skins. Breakdown of anthocyanins was higher become intimate neutral pH, but stable to stroage period for 7-days. Hyperchromic effects were showed when sugars were added in pigment extract of grape peels, the highest value was glucose and the next ordor was fructose and sucrose. Breakdown velosity of anthocyanins was higher when ascorbic acid was added, but its velocity was reduced in anaerobic state . Absorption degree by organic acid treatment was higher than control, and anthocyanins were stable to storage period for 7 days.

• Advances in environmental research
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• v.5 no.4
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• pp.237-249
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• 2016

The management of municipal solid waste (MSW) is essential for every community; and, it is currently a major challenge in Nigeria. This paper provides an overview of the current MSW management trends in Nigeria and proposes new sustainable MSW management systems. Across Nigerian cities, MSW management is characterized by inefficient collection and transportation to disposal sites. Collection services do not reach some unplanned areas and slums due to poor street network. Even some planned areas are not reached by collection services. The informal sector contributes to waste collection, resource recovery and recycling; however, their activities are not recognized by the governments. Markets exist for recovered materials but more efforts need to be geared towards intensive recovery of materials and expansion of these markets. Despite the high proportion of putrescible matter in MSW, the only form of treatment commonly used currently is open burning for volume reduction. The high organic fraction presents a great opportunity for composting and anaerobic digestion. Ultimate disposal is currently done in open dumpsites. This needs to be upgraded to engineered landfills that are properly sited and adequately operated by well trained personnel. There is an emerging waste stream of concern, electronic-waste (e-waste), that requires urgent sustainable management as e-waste are currently co-disposed with other waste streams or burnt in the open posing detrimental health impacts.

• YAKHAK HOEJI
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• v.13 no.4
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• pp.101-110
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• 1969

The isozyme alteration of lactic dehydrogenase in the tissues of albino rat inhaled SO$_{2}$ were studied in vivo and in vitro, with the following results: (1) The H-type of LDH activity relatively dominated in the normal brain, heart and kidney tissues of rat, M-type in the normal lung, liver, and muscle tissues of the animal. (2) When rats inhale SO$_{2}$ in the concentration of 250 ppm, it appears that the M-type tends to predominate in the anaerobic tissues such as liver, kidney and muscle tissues and the H-type in the aerobic tissues such as brain and heart tissues. (3) When 5% SO$_{2}$ is introduced into tissue homogenates, LDH activities in the heart, lung, liver and muscle tissues are increased more than that of introducing room-air only. With sam treatment, LDH activity is decreased in the kidney tissue and no alteration is observed in the brain tissue. (4) Although, after the aeration of SO$_{2}$, the oxygen tension seems to bring decreases in the level of LDH activity in the anerobic tissues such as liver and muscle tissues, while, on the other hand, increases in the level of the activity in the aerobic tissues, such as the brain, heart and lung tissues. (5) Accordinglly, SO$_{2}$ affects LDH activities, its isozyme pattern of each organs, and their metabolic pathway by its absorption of the gas.

• Environmental Engineering Research
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• v.15 no.1
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• pp.3-7
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• 2010

To better understand the ecology of tetrade forming organisms (TFOs) floating in a large amount of dairy wastewater treatment plant (WWTP) effluent (sequencing batch reactor [SBR]) during the inefficient phosphorus (P) removal process of an enhanced biological P removal system, the TFOs from the effluent of a full scale WWTP were separated and attempts made to culture the TFOs in presence/absence of oxygen. The intact TFOs only grew aerobically in the form of unicellular short-rods. Furthermore, to identify the intact TFOs and unicellular short-rods the DNAs of both were extracted, analyzed using their denaturing gradient gel electrophoresis (DGGE)-profiles and then sequenced. The TFOs and unicellular short-rods exhibited the same banding pattern in their DGGE-profiles, and those sequencing data resulted in their identification as Acinetobacter sp. The intact TFOs appeared in clumps and packages of tetrade cells, and were identified as Acinetobacter sp., which are known as strict aerobes and efficient P-removers. The thick layer of extracellular polymeric substance surrounding Acinetobacter sp. may inhibit phosphate uptake, and the cell morphology of TFOs might subsequently be connected with their survival strategy under the anaerobic regime of the SBR system.