• Title/Summary/Keyword: Cultures

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Effect of Hydrocarbon Uptake Modes on Oil Degradation Rate by Mixed Cultures of Petroleum Degraders (Hydrocarbon Uptake Modes에 따른 유류분해 미생물 혼합체의 원유분해능)

  • 고성환;이홍금;김상진
    • KSBB Journal
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    • v.13 no.5
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    • pp.606-614
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    • 1998
  • In this study, biodegradation rate of Arabian light crude oil by mixed cultures of selected petroleum-degraders was determined. Their modes of hydrocarbon uptake were then observed to determine whether there are differences in biodegradation rate by the mixed cultures. By the mixed cultures of petroleum-degraders having same modes of hydrocarbon uptake, such as strain US1 and K1 (using pseudo-solubilized hydrocarbons by a biosurfactants), K2-2 and P1(using hydrocarbons by direct contact), CL 180 and IC-10 (mixed type of uptake modes), the biodegradation rates of aliphatics in the crude oil were increased more than those by their pure cultures, about 40%, 25% and 20%, respectively. Biodegradation rate of strain KH3-2 (using only water- dissolved hydrocarbons) was increased by mixed cultures with strain K1, CL180 or IC-10 possessing high emulsifying activity. However, the biodegradation rate of the crude oil was decreased about 20%-40% by the mixed cultures of petroleum-degraders having different mode of hydrocarbon uptake, such as addition of strain US1 or K1 in the cultures of K2-2 or P1. Biosurfactants produced by US1 or K1 seems to enhance the emulsification of crude oil in aqueous phase but inhibit the attachment of K2-2 or P1 to crude oil. As same phenomena, the addition to Triton X-100 into the culture of strain US1, K1, CL180, IC-10 or KH3-2 increased the biodegradation rate, but the addition in the culture of strain K2-2 or P1 decreased the biodegradation rate. The mixed culture made of CL180, IC-10 and KH3-2 degraded 61.5% of aliphatics and 69% of aromatics in 3% (v/v) of Arabian light crude oil added.

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A Study on East Asia Cultural Diversity in Geography Education: Centered on "Human Relationship and Living-Habit" Culture (동아시아 상호 이해를 위한 문화 다양성 교육의 시론적 연구 -"인간관계와 생활습관" 문화를 중심으로-)

  • Kim, Da-Won
    • Journal of the Korean Geographical Society
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    • v.46 no.1
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    • pp.100-114
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    • 2011
  • The purpose of this study is to suggest the contents for geography education about East Asian cultural diversity. I chose "Human Relationship and Living-Habit" culture among East Asian diverse cultures and fixed 4 themes: family cultures, traditional cultures, friendship cultures and relationship cultures with other people. For making the lesson contents for East Asian cultural diversity, I analysed Geography 2009 Revised Curriculum and presented specific contents differently depending on grades. Until now, static and homogeneous cultures in East Asia have been emphasized mostly at school but cultures that are dynamic and related to students$^{\circ}{\phi}$ life are proposed in this study. Through understanding the differences of the East Asian cultures, it will be possible to expand mutual understandings among the East Asian people. This study will be a good alternative and paving the way for enhancing cooperations in East Asia.

Studies on the Enhanced Physiological Activities of Mixed Lactic Acid Bacteria Isolated from Fermented Watery Kimchi, Dongchimi (발효된 물김치인 동치미에서 분리한 혼합 젖산균의 생리활성 증진에 대한 연구)

  • Choi, Moon-Seop;Kim, Dong-Min;Oh, Kye-Heon
    • KSBB Journal
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    • v.30 no.5
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    • pp.245-252
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    • 2015
  • The aim of this study was to investigate the efficacy of enhanced physiological activities in cultures isolated from Korean fermented watery Kimchi, Dongchimi, of single lactic acid bacteria (LAB), and when these three are mixed LAB as probiotics. Using the BIOLOG system and 16S rRNA sequencing, the isolates were characterized, and identified and assigned to Leuconostoc mesenteroides DK-3, Leuconostoc dextranicum DK-6, and Lactobacillus curvatus DK-13, respectively. Growth rate and pH changes, production of organic acids as metabolites, and physiological activities of the single and mixed LAB cultures, were monitored and compared. In mixed LAB cultures after 72 h of incubation, the maximum concentrations of lactic acid and acetic acid were approximately 340.5 mM and 191.9 mM, respectively, and pH changed from 7.00 to 3.62. Mixed LAB cultures were able to eliminate 96.3% of nitrite. Activities of antioxidant and ${\beta}$-galactosidase were 60.3% and 16.8 units/mg, respectively. Significant antibacterial activity of the concentrated supernatants was demonstrated against several food-poisoning bacteria. Physiological activities obtained from the mixed LAB cultures have been shown to be considerably higher than those of single LAB cultures. In conclusion, these studies demonstrate that compared to the single cultures, all physiological activities in mixed LAB cultures are significantly enhanced.

A report on the Salmonella cultures isolated in Korrea(1974) (1974년(年) 한국(韓國)에서 분리(分離)된 쌀모넬라 균(菌)에 관(關)한 보고(報告))

  • Kim, Yong-Ja;Chung, Kyung-Suck;Chun, Nam-Ho;Ryu, Young-Hat
    • The Journal of the Korean Society for Microbiology
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    • v.10 no.1
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    • pp.9-12
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    • 1975
  • The authors identified 717 Salmonella cultures among 1504 suspectable cultures collected from all over the country in 1974. According to the results obtained from the physical and biochemical tests, and the antigenic formula analysis, seven cultures of S. paratyphi A, one culture of S. paratyphi B, Six cultures of S. typhimurium, one culture of S. thompson, four cultures of S. enteritidis and six hundred and ninty eight cultures of S. typhi were confirmed. The results of antibiotics-sensitivity test on Salmonella cultures revealed that chloramphenicol, gentamycin and ampicilin were considered to be the drugs of choice according to the results from the In Vitro test performed.

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Changes in the Growth and Biochemical Composition of Nannochloropsis sp. Cultures Using Light-Emitting Diodes (LED (Light Emitting Diode)를 이용한 Nannochloropsis sp.의 성장 및 생화학적 조성 변화)

  • Park, Jin-Chul;Kwon, O-Nam;Hong, Sung-Eic;An, Heui-Chun;Bae, Jea-Hyun;Park, Mi-Sun;Park, Heum-Gi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.3
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    • pp.259-265
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    • 2013
  • The marine microalgae Nannochloropsis sp. was cultured under a metal halide lamp (MH) or light-emitting diodes (LEDs) of various wavelengths (blue, LB; red, LR; yellow, LY; green, LG; white, LW); changes in growth, total carotenoid, chlorophyll a, amino acid and fatty acid profiles were investigated. LB-exposed cultures exhibited the highest specific growth rate (SGR) (0.32), whereas LY-exposed cultures showed the lowest SGR (0.18). After cultivation for 9 days, the maximum dry cell weight (g/L) of LB-exposed cultures was significantly higher than that of those exposed to other light conditions (LB>MH>LW$${\geq_-}LG{\geq_-}$$LR>LY). The essential amino acid (EAA, %) contents of cultures exposed to LG, LB, LR and MH were higher than those exposed to LY and LW (P<0.05). Eicosapentaenoic acid and n-3 highly unsaturated fatty acid levels were significantly higher in MH-exposed cultures compared to those exposed to LY (P<0.05), with no marked difference compared to those exposed to LB, LG, LR and LW (P>0.05). The total carotenoid content was highest in LR-exposed cultures (18.0 mg/L), whereas MH showed the lowest (11.8 mg/L; P<0.05). Chlorophyll a content was highest in cultures exposed to LR compared to other light sources. These results suggest consistent differences in growth and biochemical composition after exposure to light of different wavelengths.

The Role of Enzymes Produced by White-Rot Fungus Irpex lacteus in the Decolorization of the Textile Industry Effluent

  • Shin, Kwang-Soo
    • Journal of Microbiology
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    • v.42 no.1
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    • pp.37-41
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    • 2004
  • The textile industry wastewater has been decolorized efficiently by the white rot fungus, Irpex lacteus, without adding any chemicals. The degree of the decolorization of the dye effluent by shaking or stationary cultures is 59 and 93%, respectively, on the 8th day. The higher level of manganese-dependent peroxidase (MnP) and non-specific peroxidase (NsP) was detected in stationary cultures than in the cultures shaken. Laccase activities were equivalent in both cultures and its level was not affected significantly by the culture duration. Neither lignin peroxidase (LiP) nor Remazol Brilliant Blue R oxidase (RBBR ox) was detected in both cultures. The absorbance of the dye effluent was significantly decreased by the stationary culture filtrate of 7 days in the absence of Mn (II) and veratryl alcohol. In the stationary culture filtrate, three or more additional peroxidase bands were detected by the zymogram analysis.

Understanding negotiating dynamics across cultures by Indian businessmen (성공적인 국제거래를 위한 인도상인과의 협상전략에 관한 연구)

  • Park, Yang-Sup
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.43
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    • pp.457-480
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    • 2009
  • The objective of this study is to understand negotiating dynamics across cultures by Indian businessmen and suggest proper negotiating strategies to Korean businessmen when they make a deal with Indian firms. The study proposes, as a result, twelve countermeasures as effective negotiating strategies against negotiating cultures of Indian businessmen. Better understanding on business cultures of the country with which Korea makes international transactions leads more fruitful outcome in concluding the international agreement. So cross-cultural studies are very much required for successful negotiations. Recently many Korean firms want to try to penetrate into Indian market and do successful operation because India becomes a compulsory subject for most of Korean firms. To increase possibilities of success in India, such Korean firms may consider applying the suggested negotiating strategies to the Indian business fields.

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