• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.91-103
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• 1994

The floristic characteristics and ecological conservation measures for the plant resources of the Tokyusan National Park. Chollapuk-do, Korea were discussed. The field works was done for three times in nine major areas from April to July, 1993. The total number of vascular plants in this area were summarized as 97 families, 297 genera, 469 species and 541 kinds. The nineteen kinds of artificially planted, twelve kinds of Korean endemics and sixteen kinds of Korean rare and endangered species in the area were revised and compiled in the list. The flora of the area were categorized into the Southern part of the Korean Region, where the species such as Quercus serrata. Fraxinus sieboldiana, Ilex macropoda, Lindera erythrocarpa, Lindera glauca, Rubus coreanus, Taxus cuspidata, Cephalotaxus koreana and Abies koreana were roled as major floristic components in the Korean Region and endemized in the southern part of Korea. The natural communities such as Adonis amurensis Community, Taxus cuspidata Community, Betula ermanii Community, Hemerocalis spp. Community, Rhododendron tschnoskii Community, Rhododendron schlippenbachii Community, Disporum ovale Community, Tricyrtis dilatata Community, and present natural distribution of Abies koreana, and swamp vegetation in Tumunsan areas, as well as upland grassland at the summit of Hyangchokpong were represented for their floristic values in the area. The fifteen kinds of medicinal plants such as Gastrodia elata, seven kinds of ornamental plants such as Adonis amurensis, and thirteen kinds of edible plants such as Ligularia fischeri are faced potentially in endangered from the outrageous collections by the local peoples. The Action Plan for the conservation management of the area which enables sustainable use by the local peoples must be established in the near future.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.216-222
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• 2006

This study was carried out to select the lactic acid bacteria producing ${\beta}-galactosidase$ (lactase) and investigate the properties of the ${\beta}-galactosidase$. About 100 strains of lactic acid bacteria showing blue colony on the MRS agar medium containing X-gal were isolated from several kinds of Kimchi. Among them, 2 strains were selected as potential ${\beta}-galactosidase$ producers. The selected strains, ET-1 and LA-12, were identified as Lactobacillus fermentum and L. acidophilus, respectively by the analysis of 16S rDNA sequences. They showed relatively high ${\beta}-galactosidase$ activity and cellular viability. Their ${\beta}-galactosidase$ showed the highest activity at $55^{\circ}C$. And the optimum pHs of the enzymes produced by ET-1 and LA-12 were pH 5.5 and pH 7.0, respectively. They were also highly resistant to artificial gastric juice and bile. Two selected strains showed little change of viable cell number for 3 hr incubation in artificial gastric juice, and maintained the viable cell number at $10^8CFU/ml$ for 24 hr in 0.3% oxgall after incubation for 2 hours in artificial gastric juice. Based on these results, ET-1 and LA-12 are expected to be applied in dairy industry.

• Food Science and Preservation
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• v.24 no.5
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• pp.707-713
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• 2017

The objective of this study was to select yogurt starter from Korean traditional fermented foods. The 2 strains (KM24, KM32) among 50 strains of isolated lactic acid bacteria selected as starter based on milk clotting ability, antimicrobial activity against various pathogens, tolerance in artificial gastric and bile juice and growth in 10 % skimmed milk. The strains were identified as Lacobacillus plantarum (KM32) and Pediococcus pentosacesus (KM24) by 16S rRNA gene sequencing. Viable cell number of yogurt fermented with mixed strains (KM24 and KM32) was 9.66 log CFU/mL after fermentation for 48 h and maintained $10^9CFU/mL$ during fermentation for 72 h at $37^{\circ}C$. The pH and titratable acidity of mixed cultured yogurt were 4.25% and 0.83% after fermentation for 48 h at $37^{\circ}C$, respectively. The physico-chemical characteristics of mixed cultured yogurt after fermentation for 48 h were $38.45{\mu}g/mL$ (polyphenol content), 48.57% (DPPH radical scavenging activity) and 465.40 cp (viscosity), respectively. The mixed cultured yogurt maintained $10^9CFU/mL$ of lactic acid bacteria during storage 10 days at $4^{\circ}C$. The viable cell number of yogurt prepared with mixed culture(KM32+KM24) maintained higher and than that of control (L. casei) during storage. These results indicated the potential use of selected strains (KM32+KM24) isolated from kimchi as a yogurt starter with strong acid tolerance and probiotics properties.

• Restorative Dentistry and Endodontics
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• v.33 no.6
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• pp.507-517
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• 2008

There are considerable in vitro and in vivo evidences for remineralization and demineralization occurring simultaneously in incipient enamel caries. In order to "heal" the incipient dental caries, many experiments have been carried out to determine the optimal conditions for remineralization. It was shown that remineralization is affected by different pH, lactic acid concentrations, chemical composition of the enamel, fluoride concentrations, etc. Eighty specimens from sound permanent teeth without demineralization or cracks, 0.15 mm in thickness, were immersed in lactic acid buffered demineralization solutions for 3 days. Dental caries with a surface zone and subsurface lesion were artificially produced. Groups of 10 specimens were immersed for 10 or 12 days in lactic acid buffered remineralization solutions consisting of pH 4.3 or pH 6.0, and 100, 50, 25, or 10 mM lactic acid. After demineralization and remineralization, images were taken by polarizing microscopy (${\times}100$) and micro-computed tomography. The results were obtained by observing images of the specimens and the density of the caries lesions was determined. 1.As the lactic acid concentration of the remineralization solutions with pH 4.3 was higher, the surface zone of the carious enamel increased and an isotropic zone of the subsurface lesion was found. However, the total decalcification depth increased at the same time. 2.In the remineralization solutions with pH 6.0, only the surface zone increased slightly but there was no significant change in the total decalcification depth and subsurface zone. In the lactic acid buffer solutions with the lower pH and higher lactic acid concentration, there were dynamic changes at the deep area of the dental carious lesion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.749-755
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• 2014

Exopolysaccharides (EPSs) have been widely used in the food industry as viscofying, stabilizing, and emulsifying agents as well as in the pharmaceutical industry for their immunomodulatory, anti-tumor, and anti-inflammatory effects. A total of 458 lactic acid bacteria (LAB) strains isolated from several kinds of soybean pastes were screened for the production of homo-EPS (HoPS). LAB isolates were primarily screened using thin layer chromatography (TLC) and further screened polymerase chain reaction (PCR) targeting genes involved in HoPS production. Six LAB isolates producing high amounts of HoPS were identified by TLC. Among these isolates, glucansucrase gene was amplified in two strains (JSA57, JSB22), whereas the fructansucrase gene was detected in three strains (JSA57, JSB22, JSB66). After isolating the strains, their morphological characteristics and 16S rDNA sequences were determined. Six species were identified as L. alimentarius HSB15, L. plantarum JSA22, L. pentosus JSA57, L. brevis JSB22, L. alimentarius JSB66, and L. parabrevis JSB89. To evaluate the potential probiotic properties of these LAB, their survival rates against a simulated intestinal environment were determined. After 2 hr of incubation in artificial gastric juice, survival rates of JSA57, JSB90, JSB22, and JSB66 were all greater than 50%. After 2 hr of incubation in bile juice, viable cell count of JSB22 was similar with initial vial cell counts. Growth of the six LAB was screened in arabino-oligosaccharide (AOS)-containing MRS broth. Results showed that growth of the isolates selectively increased after culture in AOS-containing media. Strain JSB22 (6 hr), JSB66 (6 hr), HSB15 (20 hr), and JSA22 (29 hr) showed maximum growth rate. Especially, JSB22 showed the highest growth rate. These results suggest that EPS-producing LAB isolated from Deonjang could be applied as synbiotics.

• Women's Health Nursing
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• v.18 no.4
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• pp.279-289
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• 2012

Purpose: The purpose of this study was to explore the influence in a planned pregnancy of alcohol related family variables, knowledge and recognition of the effects of alcohol use during pregnancy on actual alcohol use during pregnancy. Methods: The participants were 284 women who had experienced a pregnancy at some time in their lives. The data were collected from December 2011 to January 2012 and the method of data collection was self-report questionnaires. The instruments for this study were AUDIT-K, Knowledge of alcohol use during pregnancy, and Recognition of alcohol use during pregnancy. Results: There were higher incidences of alcohol use during pregnancy when alcohol consumption was a problem, when there was a family member with an alcohol problem, or after having had an artificial abortion. There was no correlation in alcohol use during pregnancy with knowledge, but a correlation with recognition was found. Conclusion: The results of this study suggest that the main factor in alcohol use during pregnancy is recognition of the effects of alcohol use during pregnancy.

• Journal of Korean Academy of Nursing
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• v.3 no.2
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• pp.53-65
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• 1973

In order to explore the present status of induced abortion, a survey was conducted on 578 married women : 320 employed women, 165 urban and 93 rural housewives, during the period form June, 1972 to september, 1972. The results were as follows: 1. The rates of induced abortion in urban housewives, employed women and rural housewives were 50.3%, 30.3% and 1l.8%, respectively. 2. With regard to the duration of marital life, the rate of induced abortion was higher group of 11-16 and 17-22 years of duration than those of less than 4 years ana more than 23 years. 3. There were significant differences between housewives and the employed women. and also between urban and rural housewives in the rates of induced abortion. 4. The mean number of pregnancies was 4.9 and 4.8 for the rural and urban housewives while for the employed women was 2.1. 5. The mean number of live births was 4.5 and 3.2 for the rural and urban housewives while for the employed women was 2.1. 6. Average number of living children of the women who had experienced induced abortions was 4.8 and 3.1 for the rural and urban housewives while for the employed . women was 2.5. 7. There was a significant correlation between induced abortions and social class or educational level. The higher their level of education or social class, the more frequently women were experienced induced abortions. 8. There was a significant correlation between experience of induced abortions and family planning practice, vis., the women who had experienced induced abortions made more use of family planning practices.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.604-619
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• 2012

According to the concept of woodland aesthetic in Germany and forest design in United Kingdom, artificial forest should be restore ecologically step by step in National Park, Korea. This study was carried out to provide the density criterion of thinning for the inducement of the ecological succession by analysing of vegetational structure in Artificial Forest, National Parks. Eleven plots(size is $20m{\times}20m$) were set up in the artificial forest such as Pinus koraiensis forest, Abies holophylla forest, Chamaecyparis obtusa forest, Populus tomentiglandulosa forest, and Larix kaempferi forest and in the natural forest such as Pinus densiflora community, Pinus densiflora-Quercus serrata community, and Quercus serrata community in Chiaksan, Songnisan, Deogyusan, and Naejangsan National Parks, Korea. We classified the artificial forest into undeveloped type of succession, type of alien young trees developing, and early phase type of succession based on the vegetational structure. According to the index of Shnnon's diversity(unit: $400m^2$), undeveloped type of succession was ranged from 0.9681 to 1.1323, type of alien young trees developing was ranged from 1.0192 to 1.1870, early phase type of succession was ranged from 1.3071 to 1.3892, and natural vegetation was ranged from 1.2202 to 1.3428, therefore early phase type of succession forest and natural vegetation are more higher than simple-layered artificial forest with one needle leaf tree species. The limit for the step-by-step thinning was in the range of 30~60%. In case of undeveloped type of succession, we should thin out from large trees throughout three phases, because alien species dominated high value 88~90% in canopy layer. In case of type of alien young trees developing, we should thin out from alien young trees such as Populus tomentiglandulosa throughout one or two phases, because alien species dominated high value 60~97% and young trees with saplings growing up in understory and shrub layer. In case of early phase type of succession, we should thin out from alien trees that compete with native species throughout one or two phases, because alien species dominated less than value 30%.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.106-112
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• 2006

Fifty four acid-resistant and bile-resistant isolates of lactic acid bacteria were initially isolated from the faces of Korea native cattle and Holstein using MRS agar and LAPT agar, and ten strains with superior activity against bile salt were finally selected LS1, LS15, and LL6 isolates showed survival of 66.5%, 82.6% and 80.7% against the simulated stomach liquid(pH 2.5), respectively. LL6 and LL7 isolates had the highest inhibitory activities against the pathogenic bacteria such as Salmonella typhimurium, Staphylococcus aureus, and Clostridium perfringens. By using API 50 CHL kit LS1, LS2 and LM1 isolates were identified as a L. fermentum. LL6 and LL7 isolates as a L. acidophilus, and LS3 isolate as a L. plantarum. The other four isolates belong to genus Lactobacillus. All the isolates tested were sensitive to some antibiotics such as ampicillin, amoxicillin and erythromycin, but resistant to colistin and ciprofloxacin. LB1, LL6 and LL7 isolates were resistant to gentamicin and neomycin. Especially, the LL6 isolate showed the highest resistance to both of the simulated stomach liquid and bile salt, in addition to the highest inhibitory activities against Sal. typhimurium, Staph. aureus and Cl. perfringens.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.626-636
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• 2003

Pediococcus pentosaceus K1270 was isolated from naturally fermented kimchi and identified based on the 16S rDNA sequence as well as cultural and biochemical characteristics. This strain strongly inhibited the formation of biofilm by Streptococcus mutans Ingbritt. K1270 also showed antibacterial activity against S. mutans Ingbritt. It was observed that K1270 strain produced hydrogen peroxide on MRS agar supplemented with 3, 3, 5, 5-tetramethylbenzidine (TMB) and peroxidase and the inhibitory effect of K1270 strain on the biofilm formation was reversed by the addition of catalase in part. Culture supernatant of K1270 inhibited the biofilm formation and the multiplication of S. mutans Ingbritt. This inhibitory effect of culture supernatant was decreased slightly by the addition of catalase and abolished by heat or trypsin treatment. Thus, this study suggests that P. pentosaceus K1270 inhibit the biofilm formation through the inhibition of the replication of S. mutans Ingbritt by producing hydrogen peroxide and bacteriocin.