• Korean Journal of Soil Science and Fertilizer
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• v.37 no.3
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• pp.177-183
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• 2004

The discharge of waste nutrient solution from greenhouse to natural ecosystem leads to the accumulation of excess nutrients that results in contamination or eutrophication. There is a need to recycle the waste nutrient solution in order to prevent the environmental hazards. The amount and kind of nutrients in waste nutrient solution might be enough to grow photosynthetic microorganisms. Hence in the present study, we examined the growth and mass cultivation of cyanobacteria in the waste nutrient solution with an objective of removing N and P and concomitantly, its mass cultivation. Four photosynthetic filamentous cyanobacteria (Anabaena HA101, HA701 and Nostoc HN601, HN701) isolated from composts and soils of the Chungnam province were used as culture strains. Among the isolates, Nostoc HN601 performed faster growth rate and higher N and P uptake in the BG-II ($NO_3{^-}$) medium when compared to those of other cyanobacterial strains. Finally, the selected isolate was tested under optimum conditions (airflow at the rate of $1L\;min^{-1}$. in 15 L reactor, initial pH 8) in waste nutrient solution from tomato hydroponic in green house condition. Results showed to remove 100% phosphate from the waste nutrient solution in the tomato hydroponics recorded over a period of 7 days. The growth rate of Nostoc HN601 was $16mg\;Chl-a\;L^{-1}$ in the waste nutrient solution from tomato hydroponics with optimum condition, whereas growth rate of Nostoc HN601 was only $9.8mg\;Chl-a\;L^{-1}$ in BG-11 media. Nitrogen fixing capacity of Nostoc HN601 was $20.9nmol\;C_2H_4\;mg^{-1}\;Chl-a\;h^{-1}$ in N-free BG-11. The total nitrogen and total phosphate concentration of Nostoc HN601 were 63.3 mg N gram dry weight $(GDW)^{-1}$ and $19.1mg\;P\;GDW^{-1}$ respectively. Collectively, cyanobacterial mass production using waste nutrient solution under green house condition might be suitable for recycling and cleaning of waste nutrient solution from hydroponic culture system. Biomass of cyanobacteria, cultivated in waste nutrient solution, could be used as biofertilizer.

• Research in Plant Disease
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• v.12 no.3
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• pp.254-259
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• 2006

Bacillus spp. isolated from mushroom medium wastes were evaluated for their biocontrol potentials on control of Sclerotinia rot of lettuce. The Bacillus isolates were more effectively obtained from waste suspension when directly added into nutrient agar(NA) medium than plating on the agar medium. Totally 42 isolates obtained from the wastes B23 and B42 showed highest antifungal activity against eight fungal pathogens such as Sclerotinia sclerotiorum, Rhizoctonia solani, Pythium ultimum, Phytophthora capsici, Fusarium oxysporum, Colletotrichum gloeosporioides, Cladosporium cucumerinum, and Botrytis cinerea and B23 and B42 were finally selected for further studies. Optimal concentration of the isolates was $10ml(10^7cfu/ml)$ to suppress the Sclerotinia rot of lettuce. Supplements such as starch, glycerol, and egg-yolk successfully maintained the bacterial population for 30 days in vitro and increased bio-control potentials against the disease. The bacterial isolate B23 alone showed 72% control value, furthermore it presented 95% control value when supplemented with 0.2% of starch, glycerol, and egg-yolk. The promising Bacillus isolates B23 and B42 were identified as Brevibacillus brevis and Bacillus stearothermophillus, respectively, based on morphological and physiological characteristics according to API database.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.151-158
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• 2010

TCM-KWG (tissue culture medium waste after harvest of Korean wild ginseng) (panax ginseng) is left over of tissue culture medium used to grow Korean wild ginseng (KWG). The present study was conducted to investigate the effect of TCM-KWG on meat quality and the possible of application as additives in broiler chickens. A day old broiler chickens randomized in 6 groups (n=60/groups) were administered orally with 2, 4, 8, 16, 32 mL/L TCM-KWG through drinking water with one untreated control group. After administration for five weeks, we analyzed chemical composition and meat quality. Crude ash increased approximately 20% in TCM-KWG treatment groups as compared to control group whereas the concentration of moisture, crude protein and crude fat did not show any significant difference. Crude ash is essential to enhance skeleton formation and physiological function. TCM-KWG treatment gradually decreased the pH value of breast meat whereas it did not change the purge loss and cooking loss. The pH value of meat is important for preservation of meat for longer periods and high durability strength. These results suggest that TCM-KWG treatment may improve the quality of meat and can be apply as food additives in chickens.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.149-154
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• 2012

The adsorption and desorption behavior of biofilter-medium was investigated on the performance of an adsorption column. Continuous flow-isothermal adsorption experiments were performed to treat waste air containing such a VOC as ethanol under the same condition of > 90% relative humidity as the condition of the feed to a biofilter process. In case of feeding waste air containing ethanol of 1,000 ppmv (or 2,050 mg ethanol/$m^3$) to the adsorption system at the rate of 2 L/min, the onsets of its breakthrough and reaching the state of dynamic equilibrium at the exit had been delayed 10 and 3 times, respectively, later than those at the 1st stage sampling port. Moreover, in case of 2,000 ppmv (or 4,100 mg ethanol/$m^3$), they had been delayed 9 and 3 times, respectively. Thus, regardless of feeding concentration, the ratios of delaying period were observed to be quite consistent each other at the exit of the adsorption column. With regard to the period of desorption, the ratios of delaying period were consistent each other to be 1.5 for both cases. In addition, the effect of microbial activity and sterilization-process was studied on adsorption equilibrium. The ethanol concentration in the vapor phase of vials packed with sterilized granular activated carbon (GAC) was quite consistent to that with unsterilized GAC. However, the ethanol concentrations in the vapor phase of vials packed with unsterilized compost and the unsterilized mixture of GAC and compost were higher than those with sterilized compost and the sterilized mixture of GAC and compost, respectively.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.529-532
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• 2001

Korean food waste, one of the abundantly available but environmentally problematic organic wastes in Korea, was utilized as solid-substrate by fungal strain Aspergillus niger ATcC 6275 for the production of enzymemixture containing amylase, cellulase and xylanase. The enzyme mixture can be used as high value-added animal feed. Solid-state fermentation method yielded a 84-fold enhancement in xylanase activity compared with submerged fermentation method. The effect of incubation period, incubation temperature, pH of medium, moisture content, inoculum size and enrichment of the medium with nitrogen and carbon sources were observed for optimal production of these enzymes The optimal amylase activity of 33.10 U/g, cellulase activity of 24.41 U/g, xylanase activity of 328.84 U/g were obtained at 8 days incubation with 50%(w/w) soy bean flake, with incubation temperature of $25^{\circ}C$, pH of 6.38, optimal moisture content of 55% and with inoculum size of $3.8{\times}10^6$spore/g. Enzyme activities were enhanced when ImM $CaSO_4$, 2% Malt extract and 2% galactose were added as mineral, nitrogen and carbon enrichment respectively.

• The Korean Journal of Mycology
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• v.9 no.2
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• pp.49-66
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• 1981

The objectives of this investigation were to produce artificially an antitumor constituent by submerged culture of the mycelium of Coriolus versicolor (Fr.) Quel., to characterize the influence of various modifications of the nutrient and culture conditions with respect to the pro­duction, to determine chemical composition of the antitumor constituent, and to examine effects of the constituent on the immune response of mice. Submerged agitation of the mycelium in flasks containing a nutrient solution showed its adequate growth. Especially the mycelial growth in the medium containing glucose and yeast extract was abundant. The addition of cotton seed flour or ginseng waste to the medium increased the yield of mycelial growth and the production of the antitumor constituent. The replacement of glucose with starch also yielded the adequate growth. The antitumor constituent extracted from the mycelium and isolated from the culture filtrate was a protein-bound polysaccharide. The analyses of this constituent by GLC and amino acid autoanalysis showed that it contained four monosaccharides and fifteen amino acids. The protein-free polysaccharide of the constituent was also found to exert greater antitumor activity against sarcoma-180 in mice than the entire constituent. The antitumor constituent was found to potentiate the immune response of mice against sheep red blood cell. The protein-bound polysaccharide exerted more favorable influence on the immunity than the protein-free moiety.

• Nuclear Engineering and Technology
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• v.21 no.4
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• pp.267-276
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• 1989

A numerical model for nuclide migration through fractured rock media has been developed. Nuclide transport with groundwater in rock fissures and the diffusion of nuclides into rock matrix are considered one-dimensionally . In the safety assessment of the repository for radioactive waste, this one-dimensional model by the finite-difference scheme, which enables us not only to use more realistic boundary conditions but also to model the nonhomogeneous rock medium as the multilayered media, can be used effectively with the analytical mode. The solution by the numerical model will be verified analytically, and then extended to the double-layered rock medium transport model.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.52-52
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• 2002

Chitosan is a key compound of shrimp waste. It is a biopolymer, which is widely used in the field of medical Sciences. Chitosan-TPP (Tripolyphosphate) complex has more or less similar physical properties as Ca-alginate which can be used for the production of synthetic seeds. Possibility of the use of Chitosan-TPP complex as a matrix for encapsulation of somatic embryos was tested against the Ca-alginate complex (2.5w/v Na-alginate, 100mM CaCl2 at pH 5.5). Somatic embryos grown in the induction medium (IM) were drawn into the viscous chitosan solution (1%) and mixed well by inverting the tube carefully. Then the mixture was dropped at regular intervals into the tripolyphosphate (TPP) solution kept on a magnetic stirrer for bead formation. Synthetic seeds formed were washed and transferred into the incubation medium, then allowed either to air-dry or freeze-dry.(중략)

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.6
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• pp.618-626
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• 2017

Conventional high temperature reformers are not suitable for hybrid fuel cell systems that use waste heat as a heat source. So, development of a low temperature type reformer is needed. However, the analysis was conducted in two ways to increase the thermal efficiency, because of low reforming rate due to the low heat source. First, it is a way to ger thermal gain from the outside through partial insulation. In the case of one heat source tube and several heat source tubes, we analyzed the effect of partial heat insulation in some cases. Second, we found the most efficient arrangement of the heat source tubes by changing the location of the heat source tubes. The interpretation was carred out using the COMSOL Mutiphysics program.

• Journal of agriculture & life science
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• v.44 no.3
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• pp.7-14
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• 2010

Alternative subirrigation way, capillary wick system (CWS) was tested to reduce labor cost, waste water, contamination of ground water, and use of fungicide compared to overhead irrigation system (OIS). CWS helped reduce remarkably the working hours for watering from 4 hours in OSI to just 5 minutes. Labor cost was saved 98% in CWS compared to OIS. By the physical characteristics of various growing media, 1 coconut coir+2 perlite (v/v) mixture was selected because it had an ideal distribution of three phase, e.g. 1 solid: 1 liquid: 2 gas phase. Medium mixture containing scoria had so high bulk and particle density to hurt root. In bark-containing medium, the liquid phase and the percent saturation of liquid phase with time elapsed was lower than that of other mixture. It meant that the mixture contained very low level of water. Application of CWS for cyclamen pot production played an important role in reducing the incident of fusarium wilt symptom from 18% in conventional over watering system to 4%. Cyclamen pot irrigated by capillary wick had shorter petiole and more leaves than those by overhead watering. As a result, this system was highly beneficial to get uniform pot products with high quality. It improved water and nutrient solution efficiency relative to conventional overhead irrigation system (OIS).