• Korean Journal of Weed Science
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• v.32 no.2
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• pp.85-97
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• 2012

To investigate the usefulness of freshwater alga Water-net (Hydrodictyon reticulatum, HR) as resources for production of fermentable sugars, the easiness of enzymatic saccharification was evaluated at first. When 6 plant materials (HR, Spirulina, Chlorella, Scenedesmus, Cladophora, Corn stover) were enzymatically hydrolyzed with 2% solid loading at the same condition, HR showed the highest ratio of saccharification based on glucose production. No milled HR was also completely saccharified at the amounts of optimal enzyme mixture. Glucose yield was not changed though the citrate buffer strength for saccharification was decreased from 0.1 M to 0.1 mM. Only about 10% yield reduction was observed compared to that of $120^{\circ}C$ treatment when HR was enzymatically hydrolyzed at room temperature. The saccharification was normally occurred at $37^{\circ}C$ and pH 6.5 which is general growth condition of fermentable microrganisms, suggesting that HR have a biomass characteristics applicable for the simultaneous saccharification and fermentation. The saccharification was occurred by more than 70~80% of one of the best condition although the supplied enzyme amounts was reduced to 1/10 volume. And the glucose yield by enzymatic hydrolysis was not decreased by 10% HR solid loading and began to decrease at more than 15% solid contents. Above these results show that HR is an interesting algal biomass which is relatively easy to be saccharified by hydrolyzing enzymes. In addition, HR is a flilamentous alga and very easy to be collected. Therefore, HR seems to be an useful and valuable resources in the economical production of fermentable sugars for manufacture of bio-chemical products.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.187-193
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• 2014

As a result of the cost of grains, the replacement of grains by co-products (i.e. DDGS) in feedlot diets is a common practice. This change produces diets that contain a lower amount of starch and greater amount of fibre. Hypothetically, combining feed grade urea (U) with slow release urea (Optigen) in this type of diet should elicit a better synchrony between starch (high-rate of digestion) and fibre (low-rate of digestion) promoting a better microbial protein synthesis and ruminal digestion with increasing the digestible energy of the diet. Four cannulated Holstein steers ($213{\pm}4$ kg) were used in a $4{\times}4$ Latin square design to examine the combination of Optigen and U in a finishing diet containing different starch:acid detergent fibre ratios (S:F) on the characteristics of digestive function. Three S:F ratios (3.0, 4.5, and 6.0) were tested using a combination of U (0.80%) and Optigen (1.0%). Additionally, a treatment of 4.5 S:F ratio with urea (0.80% in ration) as the sole source of non-protein nitrogen was used to compare the effect of urea combination at same S:F ratio. The S:F ratio of the diet was manipulated by replacing the corn grain by dried distillers grain with solubles and roughage. Urea combination did not affect ruminal pH. The S:F ratio did not affect ruminal pH at 0 and 2 h post-feeding but, at 4 and 6 h, the ruminal pH decreased as the S:F ratio increased (linear, p<0.05). Ruminal digestion of OM, starch and feed N were not affected by urea combination or S:F ratio. The urea combination did not affect ADF ruminal digestion. ADF ruminal digestion decreased linearly (p = 0.02) as the S:F ratio increased. Compared to the urea treatment (p<0.05) and within the urea combination treatment (quadratic, p<0.01), the flow of microbial nitrogen (MN) to the small intestine and ruminal microbial efficiency were greater for the urea combination at a S:F ratio of 4.5. Irrespective of the S:F ratio, the urea combination improved (2.8%, p = 0.02) postruminal N digestion. As S:F ratio increased, OM digestion increased, but ADF total tract digestion decreased. The combination of urea at 4.5 S:F improved (2%, p = 0.04) the digestible energy (DE) more than expected. Combining urea and Optigen resulted in positive effects on the MN flow and DE of the diet, but apparently these advantages are observed only when there is a certain proportion of starch:ADF in the diet.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.1
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• pp.103-109
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• 2011

The objective of this study was to investigate the effect of enzymolytic products of soybean meal (ESBM), as one of the protein sources in the diet, on the growth performance, nutrient digestibility and immune function of weaned piglets. Soybean meal produced by bioprocessing with fermentation and enzymolysis contains reduced anti-nutritional factors and improved protein utilization. A total of 240 weaned piglets (Duroc${\times}$Landrace${\times}$Yorkshire, $9.01{\pm}0.22\;kg$ body weight) were randomly allocated to 4 treatments with 6 pens per treatment and 10 piglets per pen. The diets were based on corn-soybean meal and ESBM partially replaced soybean meal and soybean protein isolate at the inclusion level of 5, 10 or 15% in the basal diet. Feed intake and body weight were measured weekly. On days 24 to 27, faeces of each replicate were proportionally collected to determine the nutrient digestibility. On day 28 of the experiment, one piglet from each replicate was slaughtered humanely to collect immune organs. The results showed that inclusion of ESBM increased (p<0.05) the final weight, daily feed intake and daily gain of weaned pigs compared with the control diet, and ESBM at the inclusion levels of 10 and 15% improved (p<0.05) the feed/gain compared with the control diet. There were no differences (p>0.05) in daily feed intake among the levels of ESBM, but increasing the levels of ESBM from 5 to 15% improved (p<0.05) the final weight, average daily gain of pigs and feed/gain. The inclusion of ESBM at 5 to 15% increased (p<0.05) the digestibility of crude protein (CP) by 5 to 16%, and ESBM at 15% increased (p<0.05) the digestibility of digestible energy (DE), Ca and P compared with the control diet. ESBM increased (p<0.05) the relative weights of thymus and mandibular lymph nodes by 57.7 and 29.6%, respectively. The percentages of T lymphocytes, CD4+ and CD8+ in peripheral blood of weaned piglets were also increased (p<0.05) by feeding ESBM. The results suggest that ESBM can be a better protein source in improving growth performance, nutrient digestibility and immune function of weaned piglets.

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.308-313
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• 1999

Direct seeding is a cultivation method of Korean ginseng which can cut down production cost and increase productivity. This study was conducted to obtain detailed information about this method and to aid the development of it in Korea. Major pre-crops before ginseng cultivation were rice, corn and rye, and organic matters, such as rice straw, rye straw and poultry feces were used for basal fertilization. In direct seeding of the ginseng field, seeding density was 196 to 210 seeds per $3.3m^2$ and germination ratio was 67%. Survival ratio of 4-year-old ginsengs which were products of direct seeding was 51%, and more than 100 plants per $3.3m^2$ survived. The most critical diseases in the directly seeded ginseng field were grey mold, damping off, and stem diseases including stem spot disease. Plant growth of the ginseng cultivated by the direct seeding method was not different from the ginseng cultivated by transplanting method. But the root of the ginseng cultivated by the direct seeding method took the shape of a shorter main root compared to the ginseng cultivated by the transplanting method. Root yield per $3.3m^2$ of the direct seeding ginseng field was larger compared to the field of the transplanting cultivation.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.288-292
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• 2017

BACKGROUND: Silicon tetrachloride reacts with moisture in the atmosphere to generate hydrogen chloride, which affects the environment. Since silicon tetrachloride and its by-products are dispersed in the atmosphere in a short time after the silicon tetrachloride release into the atmosphere, it is difficult to directly assess the extent of environmental impact. In the present study, the exposure test of silicon tetrachloride or hydrogen chloride was examined in order to establish the criterion of the range affected by the silicon tetrachloride release, and the actual crops in the area exposed to silicon tetrachloride leakage were analyzed. METHODS AND RESULTS: For the experiment of exposure to silicon tetrachloride or hydrogen chloride, the leaves of red-pepper and corn were used in glass sealed containers. In the actual accident area, 59 samples from 10 different kinds of crops were collected. The pretreatment of the sample was performed by freezing and grinding, and then extracted using distilled water. The pH and concentration of chloride ($Cl^-$) ion of the extracted solution were measured using pH meter and ion chromatograph, respectively. CONCLUSION: Exposure to silicon tetrachloride caused visible damage, increasing the concentration of chloride ion, and decreasing the pH as well as hydrochloric acid. In the actual crops of the affected area, the tendency was the same as the result of the laboratory test, and the range of influence could be estimated through the concentration of $Cl^-$ ion over 2,000 mg/kg, and the correlation evaluation between the concentration of $Cl^-$ and pH. Therefore, the concentration of $Cl^-$ ion and the correlation between $Cl^-$ and pH would be considered as the factors to estimate the influence range of silicon tetrachloride release.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.119-124
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• 2001

In Conventional process, sugaring and seasoning step were combined during seasoning process of Changran-Jeotgal. While, in the case of Improved process, sugaring and seasoning step were separated and agitation was employed in order to control moisture content and improve taste. The addition of $20\%$ of corn syrup and agitation with 10 rpm for 4 hours at $20^{\circ}C$ were carried out to optimize the seasoning process in Changran-Jeotgal. From above results, quality estimation of Changran-Jeotgal manufacturing process, such as chemical and microbiological changes, there were little difference for salinity, pH, VBN value, crude fat and crude protein between Improved process and Conventional one, However water activity of Changran-Jeotgal produced by the Improved process was lower with 0.82 than that of Conventional one with 0.90. And the sensory evaluation showed that Improved process produced more favorable products; By regional groups, Seoul residents favored them more than Busan ones and by age, teen-aged like them best.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.9
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• pp.511-516
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• 2015

On this study, we investigated the removal characteristics of residual chlorine and DBPs in tap-water during boiling. Also we investigated the releasing characteristics of essential minerals in infusion tea. While recent studies focused on removal mechanisms of harmful heavy metals in infusion tea, this study tried to suggest the way to drink tap-water healthier and safer by examining releasing mechanisms of essential minerals in infusion tea. As a result, residual chlorine(initial conc. was 0.7 mg/L) was all removed in 20 minutes after heating and DBPs (the sum of THMs, HAAs and CH) were removed up to 65%. 6 kinds of essential minerals (Ca, K, Na, Mg, S, P) were released from 5 kinds of infusion tea (barley tea, corn tea, brown rice tea, cassia seed tea, solomon's seal tea) on the market. In cassia seed tea, the amount of essential minerals released from tea showed the highest values, 9.6 mg/g, and brown rice tea was the lowest, 1.6 mg/g. Particularly, the released amounts of potassium, playing a key role in human body in maintaining normal blood pressure, cell metabolism and enzyme action, showed relatively high. Through this study, we got to know that essential minerals can be obtained up to 40% of recommended nutritional intake for Korean by boiling tap-water with infusion tea.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.964-969
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• 2000

Di-(2-ethylhexyl) adipate(DEHA) has been used extensively as a plasticizer in the manufacture of plastic products such as PVC films. Though, phthalate esters plasticizers have been known to induce endocrine system-mediated responses, few studies have been conducted for the screening of estrogenic activity of DEHA, an adipate plasticizer. This study was initiated to evaluate the estrogenic activity of DEHA by in vitro E-screen assay and in vivo uterotrophic assay. MCF-7 human breast cancer cells were treated with $DEHA(5{\times}10^{-9}{\sim}5{\times}10^{-4}\;M)$, for 144 hr, and cell proliferation was determined by sulforhodamine B(SRB) assay. DEHA dissolved in corn oil was administered subcutaneously to ovariectomized(OVX) female Sprague-Dawley rats at dosage levels of 0, 2, 20 and 200 mg/kg/day for three consecutive days. Rats were sacrificed 24 hr after final treatment and vagina and uterus(wet and blotted) weights were obtained. E-screen assayed DEHA did not generate cell proliferation at treated concentrations$(5{\times}10^{-9}{\sim}5{\times}10^{-4}\;M)$, whereas 17 ${\beta}-estradiol$(E2), the positive control, induced cell proliferation at low concentrations$(5{\times}10^{-14}{\sim}5{\times}10^{-9}\;M)$. In the uterotrophic assay, DEHA did not change vagina and uterus(wet and blotted) weights at dosage levels up to 200 mg/kg/day treatment. These results demonstrated that DEHA did not exhibit the estrogenic activity as determined by in vitro E-screen assay and in vivo uterotrophic assay.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.407-414
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• 2020

To replace the sawdust in the growth medium of oyster mushroom to utilize its by-product spent mushroom substrates (SMS) as feed for ruminant, we performed cultivation test using cotton seed hull pellet (CSHP), corn stalk pellet (CSP), corncob (CC), and analyzed the feed chemical properties of those SMS. As a result of cultivation test, CC and CSHP treatment took 27 days for spawn run, 4 days for primordium formation, and 3 days for development fruiting bodies, resulting in a total cultivation period of 34 days. The yield per bottle was 134 g for CC treatment, similar to 130 g for control, while CSHP treatment (112 g) and CSP treatment (68 g) were lower than that of control. The highest biological efficiency (BE) was shown in CC treatment as 80.1%, which was 11.4% higher than 68.7% of control. The SMS of CC treatment had a relatively low content of neutral detergent fiber and acid detergent fiber, and in particular, lignin content was the lowest and crude protein content was the highest among other treatments. Therefore, CC as a substitute material for sawdust was capable of stable mushroom production and excellent nutritional value as a feed for its by-products.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.283-296
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• 2003

Emulsion-type sausages were manufactured to investigate the effects of CLA-vegetable oils and CLA-lard on quality characteristics of emulsion-type sausage. Each treatments replaced pork back fat with CLA-corn oil (CLA-CO), CLA-safflower seed oil (CLA-SSO) and CLA-lard (CLA-LD) were stored during 1, 7, 14, 21 and 28 days at 4$^{\circ}C$. The changes in physico-chemical properties, texture, thiobarbituric acid reactive substances (TBARS), fatty acid composition and CLA content of each treatments were measured during 1, 7, 14, 21 and 28 days at 4$^{\circ}C$. During storage, pH of control showed higher pH value than that of CLA-vegetable and CLA-lard treatments. The pH values of all treatments was significantly low at storage 14 days (p<0.05). The color L* and a*-value of all the treatments was not significantly changed with the storage periods. Color b*-value of CLA-treatments was higher than that of control during the storage period. Fatty acids composition was changed by addition of CLA-vegetable oils and CLA-lard. All kinds of fatty acids composition were decreased with CLA replacements than that of the control. Whereas linolenic acid content extremely increased by replacement of CLA-vegetable. CLA content of CLA-treatments was extremely increased than that of the control. The cohesiveness, springness, gumminess and brittleness of CLA-LD treatment was significantly higher (P<0.05) than that of the other treatments. The TBARS value of all treatments were significantly increased (P<0.05) as the storage period was passed. TBARS of sausage products containing CLA-CO was the lowest. Summing up the a forementioned results, emulsion-type sausage manufacturing with CLA-vegetable oil and CLA-lard was not affected in physico-chemical properties and texture characteristics. Also, it may be assumed that the high quality sausage can be manufactured with the extent of storage period and CLA accumulation.