• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1266-1270
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• 2004

Humic substances include several biological active and inactive compounds that are commonly used for improving soil fertility. Use of humic substances in swine diets is a novel concept. Humic substances contain 8,700 mg/kg of iron but its bioavailability is unknown. This study was conducted to test the bioavailability of iron in humic substances for nursery pigs. One hundred twenty five pigs (Newsham, Colorado Springs, CO) were not given supplemental iron while nursing for 21 d. Pigs were weaned on d 21 and allotted to one of five treatments (four control treatments with different levels of supplemented iron; 0, 30, 70 and 88 mg/kg from ${FeSO}_4$ and one treatment with 70 mg/kg iron from humic substances). Pigs were fed diets for 5 wk ad libitum and water was accessible freely. Body weight and feed intake were measured weekly. Blood samples were taken from pigs on d 28 to measure the number of red blood cells and hemoglobin concentration. Pigs fed a diet with the humic substances grew faster (p<0.05) during the first week postweaning, but performance was not different during the entire 5 wk period. Feed intake and gain/feed were the same among treatments. The slope ratio technique was used to estimate relative iron bioavailability. The concentration of blood hemoglobin did not respond to dietary iron levels using this model. However, the number of red blood cells (106/$\mu$l) was modeled by 4.438+0.017${\times}$ 'ron (mg/kg) from ${FeSO}_4$'0.012${\times}$'ron (mg/kg) from the humic substances' Based on the comparison between the slopes (0.012 from humic substances and 0.017 from ${FeSO}_4$), iron in humic substances was 71% as available as the iron in ${FeSO}_4$. The slopes for dietary feed intake of ${FeSO}_4$ and the iron in humic substances did not differ (p>0.05). Humic substances can replace ${FeSO}_4$ as an alternative iron source for pigs at 71% relative bioavailability.

• Journal of Soil and Groundwater Environment
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• v.13 no.2
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• pp.44-53
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• 2008

The efficiences of mineral acid (HCl), neutral salts ($CaCl_2$), and chelating agent (citric acid and $Na_2$-EDTA) were tested for extracting heavy metals from open burning and open detonation (OBOD) site soil. The extraction efficiencies of Cd, Cu, Pb and Zn from soil for various extractants were in the order of HCl > citric acid > $Na_2$-EDTA > $CaCl_2$, HCl (1.0 M) extracted effectively 82%, 86%, 80%, and 46% of initial total concentrations of Cd, Cu, Pb, and Zn, respectively. Significant negative correlations were observed between pH of extractant and amount of extracted heavy metals. Initially, examined heavy metals were predominantly bound to carbonate and Fe, Mn-oxide fraction. Though the significant amount of carbonate and Fe, Mn-oxide bounded metals were removed but a significant amount remained metals shifted to exchangeable (more mobile) fraction by HCl and citric acid extraction. The increased mobility of remaining metals could be problematic for water resources, thus careful management is needed to control the movement of heavy metals.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.59-65
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• 2008

Objectives : HRHDT has been known as a useful prescription with antibiotic, anti-inflammatory, antioxidative and immunosuppressive activity. To evaluate anti-atopic dermatitis effect of HRHDT, we treated HRHDT in NC/Nga mice model skin induced contact hypersensitivity. Methods : Contact hypersensitivity, a local inflammatory response of skin, was induced by spreading the back skin of NC/Nga mice with 0.4${\sim}$1% DNCB. HRHDT was prepared by dissolving 3% HRHDT in solution and treated 3 weeks on the back skin. Results : HRHDT significantly reduced TEWL and erythema by 0.4${\sim}$1% of DNCB treatment compared to control group. HRHDT also reduced IgE on serum obtained from blood of DNCB-treated mice. Conclusions : These results showed that HRHDT could be used as a pharmaceutical material with anti-atopic dermatitis effect by reducing IgE in contact, hypersensitivity atopic dermatitis NC/Nga mice model by DNCB.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.137-146
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• 1998

Laboratory tests were carried out to evaluate the effect of several insecticides with insect growth regulator (IGR) properties on the larval development of housefly, Musca domestica, which was collected at a large pigpen in Hamyang, Gyeongnam, Korea in 1997. Commercial formulations of the chemicals were diluted with tap water into a range of concentrations, and mixed with larval media. In addition to the IGRs, imidacloprid 5% WP was tested, too. The IGRs treated at the 2nd instar stage induced higher larval mortalities than percentages of malformed pupae. The result were, however, opposite when the IGRs were treated at the 3rd instar stage. Overall mortality resulting from larval death and malformed pupae was dependent on concentration. Diflubenzuron, teflubenzuron, triflumuron, flufenoxuron, tebufenozide, and imidacloprid, treated to the 2nd instar larvae, showed mortality over 95 % at concentrations of 5 ppm, 3 ppm, 30 ppm, 5 ppm, over 1000 ppm, 1000 ppm, respectively. Higher concentrations were needed to get the same level. of mortality in the 3rd instar larvae as that in the 2nd larvae. Overall mortality over 95% at the 3rd instar could be get at concentrations of 100 ppm, 10 ppm, 300 ppm, 10 ppm of diflubenzuron, teflubenzuron, triflumuron, flufenoxuron, respectively. Tebufenozide (1,000 ppm) and imidacloprid (300 ppm) were less effective than the other chemicals, showing only 36.7% and 86.7% mortalities, respectively. The chemicals also affected pupal weight at high concentrations. Decrease of pupal weight was distinct at high concentrations of teflubenzuron, flufenoxuron, tebufenozide, imidacloprid. Diflubenzuron and triflumuron were less effective. From these results it could be concluded that the IGR insecticides can be used as control agents by interfering with moulting and pupation process of housefly, by reducing pupal weight which could be resulted in low fertility and less oviposition.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.36-44
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• 1998

To develope cost-effective new granular formulation of mixture with 7.0% chlomethoxyfen and 3.5% butachlor, this study was conducted by investigation of floatability, dispersibility or collapsability and released concentration of active ingredients in water and bio-efficacies of the granules formulated by different formulation methods compared to commercial pellet-extruded granules. They were formulated by coating on or impregnation into extruded pellets, sands and zeolites with two active ingredients, binders, friction reducer, dispersing agents and bentonite. Pellet-coated method showed similar floatability, collapsability and bio-efficacy to the commercial pellet-extruded one or better than that but unstable patterns of released concentration of chlomethoxyfen because of easy isolation of coated technical particles from the surface of granules. Sand-coated methods showed similar physical properties, released pattern of two active ingredients, and bio-efficacy to the commercial one. Liquid binders and/or dispersing agents are more important than powdered ones to control released concentration of active ingredients from the granule mixtures, to improve the floatability and dispersibility, and to show good bio-efficacy. Sand-coated one might be a suitable method if types and amount of liquid binders and dispersing agents are selected.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.28-35
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• 1998

An antimicrobial peptide producing bacterium, Bacillus subtilis A405, was screened and identified among 700 of antagonistic bacteria. The heat-resistant antimicrobial peptide, AMP-405, was purified from the broth culture of B. subtilis A405 through $20{\sim}40%$ ammonium sulfate precipitation and ultrafiltration. The AMP-405 exhibited strong antimicrobial activities against Botrytis cinerea, Cercospora sp., Fusarium oxysporum, Penicillium digitatum, Celletotrichum gloeosporioides, Rhizoctonia solani, Pythium ultimum, Pyricularia oryzae, Escherichia coli, Pseudomonas spp. and Candida albicans. The molecular weight of the peptide was about 3.0 kDa determined by SDS-PAGE, Native-PAGE and Tris-Tricine gradient electrophoresis, and composed of 9 kinds of amino acid such as aspartic acid, glycine, serine, glutamine, valine, leucine, isoleucine, proline, tyrocine. To determine the efficiency of AMP-405 as a potential maintenance of fruits freshness, cherry tomato was srored at $25^{\circ}C$ for 2 weeks after treatment with $50{\mu}g/ml$ of AMP-405 and $10^{5}$ spores/ml of Botrytis cinerea simultaneously. Treatment with AMP-405 resulted in significantly less infection by Botrytis cinerea, than the treatment with tap water as a control.

• Journal of Aquaculture
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• v.2 no.2
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• pp.91-106
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• 1989

Chlorella has been used as a very useful food for rearing rotifer which is an important live food for early stages of fish and crustancean larvae. But Chlorella does not grow well in higher or lower temperature such as during summer or winter season in this country. Therefore, cooling or heating facilities are needed for Chlorella culture during summer or winter, but it costs too much for the commercial scale fish farmers. To solve this problem, the growth rates of 34 different species of phytoplanktons were examined at the various levels of temperatures, salinites and light intensities to select suitable species as the food for rotifers for summer and that for winter. After the suitable species were selected, growth comparisons of rotifer groups which were fed the selected species of phytoplanktons against rotifer group fed Chlorella as a control were done. Fatty acid compositions of the selected phytoplanktons and rotifer groups which were fed these selected phytoplanktons were examined. It was revealed that Nannnochioris oculata was optimum for rotifers in summer season and Phaeodactylum tricornutum was suitable for that in winter season. The optimum temperature, salinity and light intensity for former phytoplankton were $28^{\circ}C$, $33\%_{\circ}$ and 5,000 lux and those for later were $10^{\circ}C$, $30\%_{\circ}$ and 8,000 lux, respectively. In the higher temperature condition, the growth of N. oculata fed rotifer group was better than Chlorella ellipsoidea fed group. In the lower temperature condition, however, the growth of Chlorella fed rotifer group was slightly better than P. tricornutum fed group. Between two selected phytoplanktons, N. oculata has the highest content of linolenic acid (18 : 3 $\omega$ - 3, $\omega$ - 6) which is essential fatty acid for marine fish larvae. A rotifer group which was fed this plankton also showed the highest linolenic acid content among the other rotifer groups.

• Herbal Formula Science
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• v.16 no.1
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• pp.131-145
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• 2008

With tablets and powder, decoction has been a widely-used method of medicine formula. However, for these formulas have unique bitter tastes and flavors of herbal component materials as it is, the compliance of herbal medicine is severly decreased especially for female and younger patients. Consequently, expected treatment effects can't be acquired completely. If loathsome tastes and flavors of decoction were effectively reduced while pharmacological activity were kept intact, the compliance could be promoted Chong-Myung-Tang has been widely prescribed for student patients with memory This study shows that Chong-Myung-Tang+chocolate have no difference from Chong-Myung-Tang in terms of pharmacological activity. Sensory difference with net chocolate was also surved. In order to observe the difference of Chong-Myung-Tang+chocolate and Chong-Myung-Tang, memory impairment was induced by intraventricular injection of $A{\beta}_{25-35}$ peptides on mice and Chong-Myung-Tang and Chong-Myung-Tang+chocolate were administered orally for 14 days. In water maze task, improvement of learning ability during acquisition period and significant increase of memory score during retention period resulted from the treatment of Chong-Myung-Tang and Chong-Myung-Tang+chocolate with respect to the $A{\beta}-injected$ control animals. Furthermore, the $A{\beta}_{25-35}$ toxicity on the hippocampus was assessed with immunohistochemistry (Bax, TUNEL), and differences in antioxidant activity was observed through TBARS and DPPH test. We employed sensory tests using chocolate flavor, herb flavor, and bitter taste & hardness as standards to show sensory differences with net chocolate. In this study, it is demonstrated that Chong-Myung-Tang+chocolate do not disturb the pharmacological activity of Chong-Myung-Tang, and have no sensory difference with net chocolate. Chong-Myung-Tang+chocolate can be used to enhance the compliance remarkably and thought of as an effective, functional formula to maximize expected treatment.

• Polymer(Korea)
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• v.32 no.4
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• pp.322-327
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• 2008

In this study, a multi-layered pellet was composed of a seed layer including a water-swellable agent and a drug layer containing doxazosin as a model drug, a porous membrane and a castor oil layer to control drug release. The pellet is prepared by a fluidized bed coating method. To confirm drug release from polymer blending in multi-layered pellet system, it is prepared by containing different ratio such as hydroxypropylmethylcellulose (HPMC) : ethyl cellulose (EC) in drug layer and cellulose acetate(CA) : Eudragit RS in membrane. Also, to confirm the effect of oil in drug release, castor oil is coated. As a result, we observed regularly spherical pellet with diameter of $1500{\mu}m$. Release pattern of drug is confirmed by dissolution tester in aqueous media. The more the ratio of EC in drug layer, CA in membrane, and castor oil layer in pellet, the less the drug release is observed. Formation and the amount of pores in membrane is observed by SEM.

• Polymer(Korea)
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• v.32 no.2
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• pp.103-108
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• 2008

Osmotic pellet, which consisted of water-swellable seed layer, drug layer, and porous membrane layer, has been widely utilized in oral drug delivery system. In this work, we describe the preparation of osmotic pellet with nifedipine as model drug and a mixture of cellulose acetate (CA) and Eudragit RS as membrane layer, and then examined the drug release behavior on the variation of the thickness change of membrane layer (CA and Eudragit RS) and release media. Furthermore, we examined the nifedipine release behavior using sodium alginate as a potential membrane candidate. Osmotic pellet was obtained in the quantitative yield by fluidized bed coater. Osmotic pellet exhibited the round morphology and the size ranging $1500{\sim}1700{\mu}m$ in SEM. The nifedipine release decreased as the thickness of membrane layer (CA and Eudragit RS) increased. In addition, it observed that there is difference of release amount in between intestinal juice (pH 6.8) and gastric juice (pH 1.2). In the case of osmotic pellet coated with sodium alginate, nifedipine release behavior depended on the crosslinking of sodium alginate layer. In conclusion, we found that various membrane layers could control the release amount of nifedipine.