• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.236-243
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• 2009

The halophyte Leymus chinensis (Trin.) is a perennial rhizome grass (tribe Gramineae) that is widely distributed throughout China, Mongolia and Siberia. This study was conducted to investigate an optimal condition for plant regeneration from mature seeds, leaf base segments, and root segments in L. chinensis. Plant growth regulators affecting embryogenic callus induction and plant regeneration were investigated by four-factor-three-level [L9 (34)] orthogonal test in this study. The effects of explants types (mature seeds, leaf base segments and root segments), callus types, medium types were examined in this study. Wild type (WT) and Jisheng No. 1 plants (JS) were used for primary callus induction. A clear explants difference was seen during callus induction; mature seeds were considered as the preferred explants; and the highest frequency of callus induction was obtained in Medium 6 using mature seeds as explants in WT. Plant regeneration ability was evaluated by frequencies of green callus forming, shooting, rooting, and shooting with roots. Effect of α-naphthalene acetic acid (NAA) on shoot regeneration was remarkable with the highest frequency of 70.8% in WT after 2-month culture. The medium with 0.2- 0.5 mg/L NAA was found to have the highest shoot induction. All regenerated shoots were successfully rooted when transferred on half-strength Murashige and Skoog (MS) basal medium. The acclimatized plantlets were grown to mature with flowering and seeds setting in green house conditions.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.184-190
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• 2004

The influences of impeller types on morphology and protein expression were investigated in a submerged culture of Aspergillus oryzae. The impeller types strongly affected mycelial morphology and protein production in batch and fed-batch fermentations. Cells that were cultured by propeller agitation grew in the form of a pellet, whereas cells that were cultured by turbine agitation grew in a freely dispersed-hyphal manner and in a clumped form. Pellet-grown cells showed high levels of protein production for both the intracellularly heterologous protein (${\beta}$-glucuronidase) and the extracellularly homologous protein (${\alpha}$-amylase). The feeding mode of the carbon source also influenced the morphological distribution and protein expression in fed-batch fermentation of A. oryzae. Pulsed-feeding mainly showed high protein expression and homogeneous distribution of pellet whereas continuous feeding resulted in less protein expression and heterogeneous distribution with pellet and dispersed-hyphae. The pellet growth with propeller agitation paralleling with the pulsed-feeding of carbon source showed a high level of protein production in the submerged fed-batch fermentation of recombinant A. oryzae.

• Journal of Ecology and Environment
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• v.35 no.2
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• pp.79-89
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• 2012

This study was conducted with the intention of clarifying the effects of land-use types on a species of ground beetle's richness, abundance, and composition; the study focused on urban landscapes. We also selected the potential bioindicators classifying land-use types; eleven sites were selected from an urban landscape in Korea. Overall, land-use types in urban landscapes did not appear to cause significant decrease in species richness or the abundance of total ground beetle assemblage. According to habitat preferences, several land-use types and distances from the forest significantly affected the species richness and abundance, while the open-habitat species were not affected by these variables. Land-use types were classified into two major groups, forest and non-forest areas, based on ground beetle assemblage; several indicators, such as $Dolichus$ $halensis$ $halensis$ and subfamily Carabinae species, were of particular consideration. In conclusion, environmental change by anthropogenic disturbance can cause different effects on ground beetle assemblages, and forest specialists can be negatively affected.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.635-642
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• 2002

To effectively investigate the identification and distribution of the lactic acid bacteria in Kimchi, polyphasic methods, including a PCR, SDS-PAGE of the whole-cell proteins, and 16S rRNA gene sequence analysis, were used. In various types of Kimchi fermented at 20$\^{C}$, the isolate KHU-31 was found to be the predominant lactic acid bacteria. This isolate was identified as Lactobacillus sake KHU-31, based on SDS-PAGE of the whole-cell proteins and a 165 rRNA gene sequence analysis, which provided accurate and specific results. Accordingly, the approach used in the current study demonstrated that Lactobacillus sake KHU-31, together with Leuconostoc mesenteroides, were the most predominant lactic acid bacteria in all types of Kimchi in the middle stage of fermentation at 20$\^{C}$.

• Journal of People, Plants, and Environment
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• v.24 no.1
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• pp.63-73
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• 2021

Background and objective: This study was conducted to investigate the effects and preferences of horticultural therapy programs for stress relief according to MBTI personality types (Judging and Perceiving types) of female undergraduate students. Methods: The participants were divided into 15 Judging and 15 Perceiving types based on lifestyle preferences of the MBTI personality test, and a total of 30 participants participated in the horticultural therapy programs for 6 sessions. Results: Both Judging and Perceiving types showed a significant decrease in stress after participating in the horticultural therapy programs. Among the 8 life stress subfactors, Judging types showed significant stress relieving effects in 5 subfactors (relationship with the opposite sex, relationship with family, economic problems, future problems, value problems), while Perceiving types showed stress relieving effects in only 3 subfactors (relationship with family, economic problems, future problems). However, the changes in stress relief of 8 subfactors were not significantly different between the two personality types. The most preferred program for the Judging types was 'Making a flower basket', while the most preferred ones for the Perceiving types were 'Planting monstera', and 'Making preserved lemons with marigold', suggesting that the preferences varied depending on personality types. Conclusion: Therefore, it is necessary to develop suitable horticultural therapy programs for different subjects based on their personality types to enhance the effect of the programs on the subjects.

• Molecules and Cells
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• v.21 no.2
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• pp.302-307
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• 2006

Two Epstein-Barr virus (EBV) types, type 1 and type 2, maintain the same allelic specificity at four genomic loci encoding the EBNA2, -3A, -3B, and -3C proteins. We have previously described 16 EBV-transformed B-lymphoblastoid cell lines derived from Korean cancer patients, and the EBNA2 types of the EBV isolates therein. In this study, the allelic types of the EBNA2, -3A, -3B, and -3C genes of these EBV isolates were determined. We report the identification of two distinct types of naturally occurring intertypic recombinants, one with genotype EBNA2 type1/EBN3A, -3B, -3C type 2 and the other with genotype EBNA2, -3A type 1/EBNA3B, -3C type 2. The existence of these intertypic recombinants indicates that various intertypic EBV strains may be circulating in the human population, in addition to typical EBV-1 and EBV-2 strains.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1227-1235
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• 2007

Lactic acid bacteria (LAB) provide several potential health and nutritional benefits, including improving the nutritional value of food, controlling serum cholesterol levels, and controlling some types of cancer. Numerous in vitro, in vivo, human, and epidemiological studies have provided evidence of the chemopreventive effects of LAB on colon, bladder, liver, breast, and gastric cancers. These effects act via diverse mechanisms, including alteration of the gastrointestinal micro flora, enhancement of the host's immune response, and antioxidative and antiproliferative activities. This review discusses the recent progresses on the chemopreventive effects of LAB on specific cancer types and the underlying molecular mechanisms.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1814-1818
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• 2006

Vibrio cholerae O1 El Tor isolates (n=242), collected in Korea between 1991 and 2002, were classified by NotI-digested pulsed-field gel electrophoresis (PFGE). The major types were Al before 1998 and B after 1999, among both domestic and imported cases. The prevalent PFGE types among domestic cases were consistent with the prevalent types among imported cases in the same year. These results suggest a close relationship between the domestic and imported cases of cholera in Korea.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.270-276
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• 2016

Extended-spectrum β-lactamases (ESBLs), particularly those of the CTX-M types, are the predominant resistance determinants of Escherichia coli that are rapidly spreading worldwide. To determine CTX-M types, E. coli isolates were collected from retail chickens (n = 390) and environmental samples from chicken farms (n = 32) and slaughterhouses (n = 67) in Korea. Fifteen strains harboring bla_CTX-M genes were isolated from 358 E. coli isolates. The most common CTX-M type was eight of CTX-M-15, followed by six of CTX-M-1 and one of CTX-M-14. The bla_CTX-M genes were identified in the isolates from retail chickens (n = 9), followed by feces, water pipes, floors, and walls. Conjugations confirmed the transferability of the plasmids carrying bla_CTX-M genes to the recipient E. coli J53 strain. Furthermore, eight addiction systems carried by the replicons in CTX-M types were confirmed. The dominant system was identified as ccdAB, vagCD, and pndAC in donor strains and transconjugants. The clonal relationship between the two strains carrying bla_CTX-M genes indicates that E. coli may transmit from the farm to retail chickens, suggesting a possible public health risk. Our findings demonstrate that the detection of CTX-M types in E. coli isolates is important for tracking ESBL production in animals, and suggest linkage of multiple addiction systems in plasmids bearing bla_CTX-M genes.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.291-294
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• 2006

Clostridium perfringens strains were isolated from swine diarrhea in Korea. Three out of nineteen (15.8%) isolates of C. perfringens were found to be enterotoxigenic by PCR analysis. PCR-based genotyping of the three enterotoxigenic isolates of C. perfringens revealed that they were types A, C and D, respectively. These results suggest that various types of enterotoxigenic C. perfringens can cause swine diarrhea, and that the presence of enterotoxigenic type A strain, known to be strongly associated with food poisoning, may cause public health problem in Korea.