• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.4
• /
• pp.514-522
• /
• 2017

Objective: The study aimed to assess the N use efficiency (NUE) of pig slurry (in comparison with chemical fertilizer) for each regrowth yield and annual herbage production and their nutritive value. Methods: Consecutive field experiments were separately performed using a single application with a full dose of N (200 kg N/ha) in 2014 and by four split applications in 2015 in different sites. The experiment consisted of three treatments: i) control plots that received no additional N, ii) chemical fertilizer-N as urea, and iii) pig-slurry-N with five replicates. Results: The effect of N fertilization on herbage yield, N recovery in herbage, residual inorganic N in soil, and crude protein were significantly positive. When comparing the NUE between the two N sources (urea and pig slurry), pig slurry was significantly less effective for the earlier two regrowth periods, as shown by lower regrowth dry matter (DM) yield, N amount recovered in herbage, and inorganic N availability in soil at the 1st and 2nd cut compared to those of urea-applied plots. However, the effect of split application of the two N sources was significantly positive at the last two regrowth periods (at the 3rd and 4th cut). The two N sources and/or split application had little or no influence on neutral detergent fiber (NDF) content, acid detergent fiber (ADF) content, and in vitro DM digestibility, whereas cutting date was a large source of variation for these variables, resulting in a significant increase in in vitro DM digestibility for the last two regrowth periods when an increase in NDF and ADF content occurred. Split application of N reduced the N loss via nitrate leaching by 36% on average for the two N sources compared to a single application. Conclusion: The pig slurry-N was utilized as efficiently as urea-N for annual herbage yield, with a significant increase in NUE especially for the latter regrowth periods.

• Membrane Journal
• /
• v.20 no.2
• /
• pp.142-150
• /
• 2010

A series of anion exchange composite membranes were prepared and characterized for electrodialysis processes used in the removal of nitrate nitrogen and ions in groundwater. The membranes were prepared as follows; first, fabric substrates were fully impregnated with monomer mixtures of vinylbenzylchloride (VBC), divinylbenzene (DVB), Styrene (ST) and $\alpha,\alpha$-Azobis(isobutyronitrile) (AIBN). Second, they were thermally polymerized to yield crosslinked poly (VBCST- DVB)/fabric composite membranes. Finally, the membranes were treated with trimethylamine (TMA) / acetone to give $-N^+(CH_3)_3^-$-containing poly(VBC-ST-DVB)/fabric membranes. The basic membrane properties such as ion exchange capacity (IEC), electric resistance and water content of the resulting membranes were measured as a function of VBC/DVB and TMA/Acetone content. As a result, the composite membranes showed lower electric resistance and higher IEC than commercial anion exchange membranes (AMX, Astom). Electrodialysis tests using the prepared membranes were carried out for the removal of various ions such as $NaNO_3$, $MgSO_4$ and NaF for 60 minutes. The results showed that the ions were removed below 1 mg/L within about 15 minutes which indicates that the anion exchange membranes prepared here could be applied to the electrodialysis process. as can be seen in the following that the ion conductivity values were almost no change after 15 minutes electrodialysis.

• Journal of Life Science
• /
• v.27 no.3
• /
• pp.339-345
• /
• 2017

Carotenoids are natural lipid-soluble pigments, which are produced primarily by bacteria, algae, and plants. Many studies have focused on the identification, production, and utilization of natural sources of astaxanthin from algae, yeast, and crustacean byproducts as an alternative to the synthetic pigment, which is mostly used today. The aim of the present study was to identify a mutant of Paracoccus haeundaensis by exposure to UV and ethyl methanesulfonate (EMS). The mutant was then exposed to nutrient stress conditions to isolate an astaxanthin-hyperproducing strain, followed by characterization of the mutant. The survival rate decreased in accordance with an increase in the UV exposure time and an increase in the EMS concentration. A mutant of the original P. haeundaensis strain was identified that showed hyperproduction of astaxanthin following exposure to UV irradiation (20 min) and EMS treatment (0.4 M concentration). The optimal culture conditions for the PUE mutant were $25^{\circ}C$, pH 7-8, and 3% NaCl. The effects of various carbon and nitrogen sources on the growth and astaxanthin production of PUE were examined. The addition of 1% raffinose and 3% potassium nitrate influenced cell growth and astaxanthin production. The selected mutant exhibited an increase of 1.58 folds in astaxanthin content compared to initial wild type strain. A genetically stable mutant strain obtained using mutagen (UV irradiation and EMS treatment) may be a suitable candidate for further industrial scale production of astaxanthin.

• Korean Journal of Environmental Agriculture
• /
• v.17 no.2
• /
• pp.132-135
• /
• 1998

This study was conducted to obtain basic information for soil improvement in flower crop cultivating greenhouse soil through survey on the chemical and physical properties of greenhouse soils. Total of 85 Flowcultivating farms were surveyed and analysis was done on the soil characteristics, amounts of chemical fertilizer and soil amendmentuse. The result are as follows: In soil properties of flower cultivating greenhousees, silt clay loam was 51%and 68% of the surveyed soils had good drainage condition. Ground water table was over 90-120cm which was optimum range for flower cultivation. Flower cultivating farms had problem with accumulation of fertility. Nitrate nitrogen was accumulated in Gypsophila paniculate farms and available phosphorus, and exchangeable postassium were significantly higher in greenhouse soils about 2 times than in open field soil. Application amount of chemical feltilizers in greenhouses were nitrate 211,phosphorus 135, and potassium 132kg/ha, respectively. Amount of organic matter used in greenhouse were high in order of cattle manure> compost> organic fertilizer> poultry manure> swine manure and their application amounts were69, 103, 32, 20, and 43 MT/ha, respectively.

• The Korean Journal of Mycology
• /
• v.39 no.2
• /
• pp.91-98
• /
• 2011

Oudemansiella mucida, an edible and medicinal mushrooms belonging to Tricholomataceae of Basidiomycota, has been known to produce antifungal substances to inhibit the mycelial growth and spore germination of the plant pathogenic fungi. To produce good amount of antifungal substances from culture media, the optimal culture conditions of O. mucida were investigated. The most favorable conditions for the mycelial growth were $25^{\circ}C$ and pH 5 in potato dextrose agar. The most favorable carbon and nitrogen sources promoting mycelial growth were maltose and calcium nitrate, respectively. The optimum C/N ratio was about 20 : 1 in case that 3% glucose was supplemented to the basal medium as a carbon source. The optimal mycelial growth of O. mucida was found in the Hennerberg medium. The crude extract from submerged culture of potato dextrose broth exhibited inhibition of mycelial growth of Colletotrichum acutatum, Botrytis cinerea and Pyricularia oryzae but, fungicidal activity is not good enough to compared with commercially available fungicides tested. Therefore, the antifungal substances extracted from submerged culture of O. mucida might have a potential to be used for biocontrol agent of fungal diseases of plants.

• Journal of Life Science
• /
• v.17 no.1 s.81
• /
• pp.137-142
• /
• 2007

For the production of natural pigments with microbe, the strains which produced monascus pigment were isolated, and then culture condition and extraction condition were investigated. These results are summarized as follows; The strain which ran produce monascus natural pigment was isolated from natural microbial sources and we made mutant of this strain with UV($235_{nm}$, 30 second) irradiation. The mutant was identified as Monascus sp. MK2-2. The optimal culture conditions were investigated optimal medium containing 0.3% rice powder, 0.2% yeast extract, 0.3% $NH_4H_2PO_4$ and $30^{\circ}C$ in a rotary shaker (120 rpm) for 5 days (initial pH 5.0), while the pigment production was determined at 24 hr intervals. The effective carbon sources were wheat flour > rice powder > fructose, and effective nitrogen sources were sodium nitrate > $KNO_3$ for production of the monascus natural pigment. The pigment capacity is good from 17 to 22 in C/N ratio. The production amount of monascus natural pigment was 0.38 g per 1 kg of rice. Also, extract of red yeast rice had anti-thrombosis activity like a degree of aspirin.

• Korean Journal of Microbiology
• /
• v.41 no.1
• /
• pp.1-7
• /
• 2005

Methylophaga aminosulfidovorans SK1 (KCTC 10323 BP) can utilize trimethylamine as a sole carbon, nitrogen, and energy source. The bacterial flavin-containing monooxygenase (bFMO) gene was identified in the strain and the recombinant enzyme expressed in E. coli oxidized trimethylamine. To study the function and regulation of the bfmo, over 8,000 nucleotide sequences of the neighboring regions including the bfmo were determined. Three open reading frames proceeding to the bfmo gene encoded analogues to highly conserved nitrate/nitrite sensing two-component system regulators and a methyl accepting protein. Two small open reading frames just downstream of the bfmo gene showed no similar proteins of known functions but the sequences were conserved among other bacteria. Reverse transcription-polymerase chain reaction analysis showed that the six putative genes consisted of three transcription units. The three regulatory genes located upstream of the bfmo gene formed two separate transcription units. The bfmo and the two downstream genes were transcribed from a single promoter.

• Journal of Environmental Science International
• /
• v.11 no.3
• /
• pp.183-189
• /
• 2002

Investigation was carried out to observe the dominant bacteria and the effect of metals(Cd ＆ Zn) and its nitrate compound on growth of bacteria isolated from the three tributaries and lower reach of the Nakdong River. Mean CFU(log$_{10}$) level was highest in Kumho River(8.30 CFU), Nam River, Hwang River, and Mulgum followed. Staphylococcus xylosus, Staph. lentus, Pasteurella pneumotropica, Aeromonas hydrophilla were dominant species in each study site. Cadmium powder and Zinc powder showed strong effect to inhibit the growth of Micrococcus spp., Pasteurella pneumotropica, Aeromonas hydrophilla. But, nitrate compounds of Cd and Zn(Cd(NO$_3$)$_2$4$H_2O$, Zn(NO$_3$)$_2$6$H_2O$) did not clearly show the strong effect to inhibit the growth of dominants.s.

• KSBB Journal
• /
• v.8 no.3
• /
• pp.193-199
• /
• 1993

To find out the optimum conditions for indigo cell culture in air-lift bioreactor, effects of media composition including nutrients and precursors of the indigo colorants on the cell growth and characteristics of the cell growth under various cultural conditions were analyzed. Optimum cultural conditions were tested and the growth characteristics were analyzed in external and internal loop type air-lift bioreactors during 14-day culture. Better cell growth was obtained when the inoculum size was higher in the range of 0.5∼2.5% packed cell volume tested. In the sucrose concentration of 2 to 4%, the cell growth was better when the sucrose concentration was 4% (w/w) in both types of reactors. Sucrose was used up in the early stage of exponential phase of growth At the optimum concentration of a Precursor tryptophan at 1 U UW was 3.8 g/l in internal loop bioreactor, and 3.5 g/l in external one after 14 days of cultivation. Addition of indole showed negative effect on cell growth of suspension culture in air-lift biorector culture and cell mass of 2.5 g/l and 2.2 g/l were obtained in external and internal loop bioreactor, respectively. Selected inorganic nitrogen source potassium nitrate showed about 110% increase in cell growth than that of control. DCW was 16.34 g/l under optimum conditions during 14-day cultivation in internal loop bioreactor.

• Journal of Bio-Environment Control
• /
• v.6 no.1
• /
• pp.27-33
• /
• 1997

This experiment was carried out to investigate the effects of limited nutrient supply during 21 days before and after pollination stage on the growth, fruit quality and nutrient uptake of muskmelon in rockwool culture. Muskmelon, cv. Earl's Favorite seeds sowed on rockwool cube and transplanted on rockwool slab($90\times15\times7.5cm$) when 2 to 3 true leaf appeared on Sep. 6, 1991. Three kinds of nutrient composition recommended by Shizuoka university, combinated with the composition of Otsuka house A and composition Shizuoka III. One half of calcium nitrate(Ca(NO$_3$)$_2$.4$H_2O$) for limiting nitrogen supply during 21 days was treated and then fertigated the nutrient composition recommended by Shizuoka university up to harvest time. Trickling nozzles(Netafim Co. Israel) were used for fertigation of nutrient solution and noncirculating system was employed. Temperature was maintained $18^{\circ}C$ in night but 23 to $25^{\circ}C$ for 10 days after pollination for softening the fruit. The drainage ratio of nutrient solution was adjusted 20 to 30 percent. Fertigated and drained amount, and the pH and EC of nutrient solution were recorded. The concentrations of mineral elements including N, P, K, Ca, and Mg were analyzed and compared among treatments. In both autumn and winter cultivation, the limitation of nutrient supply by adjustment of nutrient composition(NO$_3$-N : 8meㆍ$\ell^{-1}$) caused the nutrient deficiency in muskmelon plant due to the limited nutrient supply. After pollination nutrient limitation by the lowering the nitrate retarded the over thickening of upper leaves of muskmelon but plant height and fresh weight of fruit were higher in the plot of nonlimited nutrient supply. The phenomena were attributed to the differences of the amount of nutrient uptake due to the limited time of nutrient solution, duration of nutrient supply and concentration of nutrient solution. These results suggested that increasing nutrient supply in the pollination stage was favorable for better appearance of fruit and improving fruit quality. Further trials would be required for the incre-ment of sugar degree of muskmelon grown in rockwool.