• Applied Biological Chemistry
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• v.50 no.4
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• pp.268-275
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• 2007

Diversity of the mud flat microbial population in Suncheon Bay was investigated by studying extracellular enzyme activities and 16S rDNA sequences. Four culturable bacterial strains with CMCase, xylanase and protease activities were isolated from the wetland and the mud flat. All the strains produced more xylanase activity than CMCase or protease activity, and the properties of the isolate enzymes from the wetland were similar to those from the mud flat. About 2,000 clones were obtained with the 16S rDNA amplified from the metagenomic DNA isolated from the mud samples. Based on the restriction pattern(s), seventeen clones were selected for base sequence analysis. Of the 17 clones, only 35% (6 clones) were found to be cultured strains and 65% (11 clones) to be uncultured strains. The similarities in the base sequences of the clones ranged from 91.0% to 99.9% with an average similarity of 97.3%. The clones could be divided into 7 groups, Proteobacteria (9 clones, 52.9%), Firmicutes (3 clones, 17.6%), Bacteroidetes (1 clone), Flavobacteria (1 clone), Verrucomicrobia (1 clone), Acidobacteria (1 clone), and Chloroflexi (1 clone). Most of the Proteobacteria clones were gamma Proteobacteria associated with oxidation-reduction of sulfur.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1328-1334
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• 2010

Low-trans spread fat (LTSF) was produced by lipase-catalyzed synthesis of canola (CO) and fully hydrogenated soybean oil (FHSBO) at 65:35 (w/w). Blend of CO and FHSBO with 65:35 ratio was interesterified using Lipozyme TLIM (immobilized Thermomyces lanuginosus, 20% of total substrate) in a 1 L-batch type reactor at $70^{\circ}C$ with 500 rpm for 24 hr. Then, physicochemical melting properties of LTSF were compared with commercial spread fat. At $20^{\circ}C$, solid fat contents (SFC) of commercial spread fat as a control and LTSF were similar, showing 19.1 and 18.1%, respectively. Major compositional fatty acids of LTSF were C18:0, C18:1 and C18:2 (29.2, 41.8 and 13.3 wt%, respectively). Trans fatty acid content of the LTSF (0.2 wt%) was lower than that of commercial spread fat (5.5 wt%). In the RP-HPLC analysis from LTSF, major triacylglycerol (TAG) molecules were SOL (stearoyl-oleoyl-linoleyl), SOO, POS/PSP, and SOS. Also, polymorphic form and x-ray diffraction of LTSF showed coexistence of $\beta$' and $\beta$ form crystals.

• Journal of Environmental Impact Assessment
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• v.27 no.2
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• pp.203-214
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• 2018

The purpose of this study is to estimate the concentrated distribution area of nutria (Myocastor coypus) and potential suitable habitat and to provide useful data for the effective management direction setting. Based on the nationwide distribution data of nutria, the cross-validation value was applied to analyze the distribution density. As a result, the concentrated distribution areas thatrequired preferential elimination is found in 14 administrative areas including Busan Metropolitan City, Daegu Metropolitan City, 11 cities and counties in Gyeongsangnam-do and 1 county in Gyeongsangbuk-do. In the potential suitable habitat estimation using a MaxEnt (Maximum Entropy) model, the possibility of emergency was found in the Nakdong River middle and lower stream area and the Seomjin riverlower stream area and Gahwacheon River area. As for the contribution by variables of a model, it showed DEM, precipitation of driest month, min temperature of coldest month and distance from river had contribution from the highest order. In terms of the relation with the probability of appearance, the probability of emergence was higher than the threshold value in areas with less than 34m of altitude, with $-5.7^{\circ}C{\sim}-0.6^{\circ}C$ of min temperature of the coldest month, with 15-30mm of precipitation of the driest month and with less than 1,373m away from the river. Variables that Altitude, existence of water and wintertemperature affected settlement and expansion of nutria, considering the research results and the physiological and ecological characteristics of nutria. Therefore, it is necessary to reflect them as important variables in the future habitable area detection and expansion estimation modeling. It must be essential to distinguish the concentrated distribution area and the management area of invasive alien species such as nutria and to establish and apply a suitable management strategy to the management site for the permanent control. The results in this study can be used as useful data for a strategic management such as rapid management on the preferential management area and preemptive and preventive management on the possible spreading area.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.398-410
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• 1982

Summer crops grown in uplands are greatly diversified and show a large variation in difference with year and location in Korea. The principal factor for the variation is weather, in which precipitation and temperature play a leading role and such a weather factors as wind, sun lights also influence production of the summer crops. Since artificial control of weather conditions as a main stress factor for crop production is almost impossible, it must be minimized only by an improvement of cultivation techniques and crop improvement. Precipitation plays a role as one of the most important factor for production of the summer crops and it is considered in two aspects, drought and excess moisture. This country, which belongs to monsoon territory, necessarily encounter one of this stress almost every year, even though the level is different. Therefore, the facilities for both drought and excess moisture are required, but actually it is not easy to complete for them. On this account, crops tolerant to drought, excess moisture and pests should be considered for establishing summer crops. For the districts damaged habitually every season, adequate crops should be cultured and appropriate method of planting, drainage and weed control should be applied diversely. Injuries by temperature is mainly attributed to lower temperature particularly in late fall and early spring, although higher temperature often causes some damages depending upon the kind of crops. Sometimes, lower temperature in summer season playa critical role for yield reduction in the summer crops. However, certain crops are prevented to some extent from this kind of stress by improving varieties tolerant to cold, hot weather or early maturing varieties. As is often the case, control of planting time or harvesting is able to be a good management for escaping the stress. Lodging, plant diseases and pests are considered as a direct or indirect damage due to weather stress, but these are characters able to be overcome by means of crop improvement and also controlled by other suitable methods. In addition, polytical supports capable of improving constitution of agriculture into modern industry is urgently required by programming of data for the damages, establishment of damage forecasting and compensation system.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.272-278
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• 2013

To evaluate the effect of surface contaminated with Escherichia coli O157:H7 (E. coli O157:H7) on the microbiological safety of lettuce, this study was conducted to investigate the attachment, biofilm producing, survival, and cross-contamination of E. coli O157:H7 on stainless steel and polyvinyl chloride (PVC). The attachment rate of E. coli O157:H7 on PVC was 10 times higher than that on stainless steel after exposure 1 h in cell suspension. However, there was not a difference between two types of surface after exposure for 6 h and 24h. The biofilm producing of E. coli O157:H7 was TSB > 10% lettuce extracts > 1% lettuce extracts > phosphate buffer. When two kinds of materials were stored at various conditions ($20^{\circ}C$ and $30^{\circ}C$, relative humidity (RH) 43%, 69%, and 100%), the numbers of E. coli O157:H7 at $30^{\circ}C$, RH 43% or RH 69% were reduced by 5.0 log CFU/coupon within 12 h regardless of material type. Conversely, the survival of E. coli O157:H7 at RH 100% was lasted more than 5 days. In addition, the reduction rate of E. coli O157:H7 was decreased in the presence of organic matter. The transfer efficiency of E. coli O157:H7 from the contaminated surface to lettuce was dependent upon the water amount of the surface of lettuce. Especially, the transfer rate of E. coli O157:H7 was increased by 10 times in the presence of water on the lettuce surface. From this study, the retention of E. coli O157:H7 on produce contact surfaces increase the risk cross-contamination of this pathogen to produce. Thus, it is important that the surface in post harvest facility is properly washed and sanitized after working for prevention of cross-contamination from surface.

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.128-137
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• 2004

For the purpose of making a functional drinkable yoghurt, new types of drinkable yoghurts were prepared from skim milk added with 0.25％ chlorella extract powder and 2.5-10.0％ chlorella extract liquid. Quality characteristics of the drinkable yoghurts were evaluated in terms of quality-keeping property(pH, titratable acidity, number of viable cells) and sensory properties. When the drinkable yoghurts containing chlorella extract(0.25％ chlorella powder and 2.5-10.0％ chlorella extract liquid) were kept at 4$^{\circ}C$ and 20$^{\circ}C$ for 15days, the pH(pH 4.13-4.27), titratable acidity(0.66-0.75％) and number of viable cell counts of the lactic acid(8.42-8.89 log CFU/$m\ell$) were not significantly changed for all drinkable yoghurts during the storage at 4$^{\circ}C$ for 15days, but the pH(pH 3.53-3.56) and titratable acidity(1.30-1.37％) and number of viable cell counts(9.15-9.45 log CFU/$m\ell$) were markedly changed for the storage at 20$^{\circ}C$ for 15days. Therefor the keeping quality of the drinkable yoghurts with addition of chlorella extract was relatively good at 4$^{\circ}C$ for 15days. The results of sensory evaluation of the drinkable yoghurts containing chlorella extract indicated that color, chlorella taste, aftertaste and overall acceptability of the drinkable yoghurt with no addition of chlorella extract showed higher preference than others. And also sensory scores of the yoghurt added with 20％ oligosaccharide were significantly higher than other groups in aftertaste and overall acceptability.

• Korean Journal of Poultry Science
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• v.29 no.3
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• pp.157-170
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• 2002

This experiment was conducted to investigate the change of egg qualify by the height of thick albumen of egg, storage temperature and storage period. The albumen index and Haugh unit were measured and compared among five different storage periods(0, 2, 4, 6, and 10 days), four different storage temperatures($15^{\circ}C$ , $20^{\circ}C$ , $25^{\circ}C$ and $30^{\circ}C$ ), and five different Parts(0, 3, 6, 9, and 12 mm) aparted from egg yolk. The albumen index and Haugh unit were as follows: the albumen index of eggs was significantly(P<0.01) different by the storage temperature and by the measuring position of thick albumen of eggs. It means that the albumen index can be differed by the measuring position of thick albumen even if eggs have a same qualify. For measuring egg qualify in this country, it should be announced that which Parts in thick albumen of eggs are measured. The albumen index of fresh eggs was 0.16. However, the index when measured at 3 hour after oviposition was lower than 0.16. Therefore, it indicates that the criterion of 0.06 lower than 0.16 is required to set for considering practical point during the marketing periods of eggs. When the criterion of albumen index puts 0.06, it is as 100%. Therefore, eggs can be kept the same quality for 6, 4 and 2 days when eggs were stored at $15^{\circ}C$ , $20^{\circ}C$ and 25 ~$30^{\circ}C$ , respectively. When the criterion of Haugh unit score puts 79 as 100%, the eggs can be maintained the quality for 6, 4, and 2 days when eggs are stored at $15^{\circ}C$ , $20^{\circ}C$ and 25~$30^{\circ}C$ , respectively. When the criterion of Haugh unit 55 as 100%, the eggs can be maintained the same quality for 10, 8 and 2 days when eggs are stored at $15^{\circ}C$ , $20^{\circ}C$ and 25~$30^{\circ}C$ , respectively. From the experimental results, it can be considered that calculathing egg quality by the height of thick albumin of eggs which was measured at the attachment Parts of thick albumin layer and yolk of eggs was most reasonable and suitable when considering the marketing periods of eggs.

• Korean Journal of Medicinal Crop Science
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• v.5 no.3
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• pp.225-231
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• 1997

This study was conducted to evaluate the growth and yield by sowing times and spacing using machine seeder on Coix Lachryma-jobi L. var ma-yuen $S_{TAPF}$. Adlay was seeded at four different dates (April 20, May 5, May 20 and June 5). Planting spaces were controlled by the seed roller of tractor drill seeder attached to tractor at three spacing ($60{\times}15cm,\;70{\times}15cm\;and\;80{\times}15cm$). The results were summarized as follows. Required days to emergence and days to anthesis were shortened as sowing date was late. But days to maturity were prolonged when sowing date was late. The accumulated temperature increased such as required periods increased. In growth characteristics, culm length was significantly different at different sowing times. But all growth characteristics was not affected by different spacings. In yield components, 1,000 grain weight and ripening rate were significantly different at different sowing times, also the number of tillers and branches was significantly affected at different spacings. Grain yield/ha was significantly different at different sowing times. But it was not significantly different at different spacings. Thus, in order to improve the yield of adlay using drill seeder, if it is not frost, sowing should be done as early as possible. As a result, suitable sowing time was April 20 with spacing at $60{\times}15cm$ using machine seeder in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.2
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• pp.118-126
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• 1986

Vibrio vulnificus is a recently recognized halophilic organism that nay cause serious human infections. Patients infected with V. vulnificus often have a history of exposure to the sea, suggesting that the organism may be common inhabitant of marine environment. The purpose of this experiment is to investigate the distribution and bacteriological characteristics of V. vulnificus. The strain used in this experiment was isolated from sea water and sea products such as common octopus (Octopus variabilis), ark shell (Anadara broughtonii), blue crab (Ericheir japonica), and sea squirt (Synthia roretzi) collected in Pusan area from July to October in 1985. V. vulnificus was frequently isolated in August when temperature of sea water was around $26^{\circ}C$ and rarely isolated in October when temperature of sea water was around $18.5^{\circ}C$. The distinctive biochemical characteristics of V. vulnificus were ONPG hydrolysis positive and fermented lactose and not grown in peptone water contained $8\%$ NaCl. The optical density at 660 nm of the growth of V. vulnificus was reached maximum level after 8 hours of culture at $35^{\circ}C$ in brain heart infusion broth but that of V. vulnificus was little increased at $15^{\circ}C$ for 14 hours. Optimum temperature and pH for the growth of V. vulnificus were around $35^{\circ}C$ and 8.0. The specific growth rate and the generation time of V. vulnificus isolated from the samples were $1.21\;hr^{-1}$, 34 min at $35^{\circ}C$ and $0.61\;hr^{-1}$, 69 min at $25^{\circ}C$, respectively. V. vulnificus did not grow on eosin-methylene-blue agar, salmonella-shigella agar, deoxycholate agar but grew well on Endo agar, xylose-lysine-deoxycholate agar and hektoen enteric agar. On Endo agar, the colonies of V. vulnificus were red and achieved a diameter of 2 to 4 mm as a feature enabling differentiation of V. vulnificus from other Vibrio spp. V. vulnificus grow well on TCBS agar forming green colonies. V. vulnificus refrigerated at $4^{\circ}C$ exhibited a linear decline of its viablity as 1 log cycle in every 16 hours storage, while V. vulnificus freezed at $-18^{\circ}C$ almost became extinct.

• Journal of the Korean earth science society
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• v.22 no.5
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• pp.405-414
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• 2001

Jecheon granite can be divided into two types; porphyritic granite (K-feldspar megacryst bearing) and medium-grained biotite granite. Porphyritic granite, host body of feldspar deposits, is 8${\sim}$11 km in diameter and about 80 $km^{2}$ in area. It mainly contains K-feldspar, plagioclase, biotite and quartz, and magnetite, zircon, sphene and apatite are accessary minerals. Enclosed minerals in K-feldspar megacryst with 3${\sim}$10 cm in diameter are hornblende, plagioclase, quartz, magnetite, apatite, sphene and zircon. Mafic enclaves mainly consisting of hornblende, plagioclase and quartz are frequently observed in porphrytic granite. Medium-grained biotite granite consists of K-feldspar, plagioclase, biotite and hornblende as main, and hematite, muscovite, apatite and zircon as accessary minerals. Core and rim An contents of plagioclase from porphyritic granite, medium biotite granite, K-feldspar megacryst, and mafic enclave are 36 and 21, 40 and 32, 37 and 32, and 43 and 36, respectively. $X_{Fe}$ values of hornblende are 0.57 at biotite granite, 0.51 at K-feldspar mehacryst and 0.45 at mafic enclave. $X_{Fe}$ values of biotite and hornblende are homogeneous without chemical zonation. K-feldspar megacryst shows end member of pure composition with exsolved thin lamellar pure albites. Characteristics of mineral compositions and petrography indicate porphyritic granite is igneous origin and medium-grained biotite granite comes from the same source of magma; biotite granite is initiated to solidly and from residual melt porphyritic granite can be formed. Possibly K-feldspar megacrysts are formde under H$_{2}$O undersaturation condition and near K-feldspar solidus curve temperature; growth rate is faster than nucleation rate. Mafic enclaves are thought to be mingled mafic magma in felsic magma, which is formed from compositional stratigraphy. Estimated equilibrium temperature and pressure for medium-grained biotite granite are about $800^{\circ}C$ and 4.83${\sim}$5.27 Kb, respectively.