• Korean Journal of Ecology and Environment
• /
• v.54 no.3
• /
• pp.156-169
• /
• 2021

Traditional morphological identification difficulties, such as phenotypic plasticity, misidentification of cryptic species, and larval stage species, can be compensated for by using DNA analysis techniques, such as DNA barcoding, in surveying zooplankton populations, including species identification. Recently, the rapid development of DNA sequencing techniques has allowed DNA-based community analysis not only for zooplankton assemblages in various aquatic ecosystems but also for the gut contents of zooplankton that are limited by conventional methods such as visual and microscopic identification. Therefore, the application of DNA sequencing can help understand biological interactions through the analysis of zooplankton food sources. The present paper introduces the major DNA-based approaches in zooplankton research topics, including taxonomic approaches by DNA barcoding, community-level approaches by metabarcoding, and gut content analyses, summarizes the analysis methods, and finally suggests the methodological topics that need to be considered for future applications.

• Journal of Soil and Groundwater Environment
• /
• v.14 no.3
• /
• pp.57-67
• /
• 2009

In soil and sediment environment, microorganisms play major roles in biochemical cycles of ecological significant elements. Because of its ecological significance, microbial diversity and community structure information are useful as indexes for assessing the quality of subsurface ecological environment and bioremediation. To achieve more accurate assessment, it is requested to gain sufficient yield and purity of DNA extracted from various soil and sediment samples. Although there have been a large number of basic researches regarding soil and sediment DNA extraction methods, little guideline information is given in literature when choosing optimal DNA extraction methods for various purposes such as environmental ecology impact assessment and bioremediation capability evaluation. In this study, we performed a thorough literature review to compare the characteristics of the current DNA extraction methods from soil and sediment samples, and discussed about considerations when selecting and applying DNA extraction methods for environmental impact assessment and bioremediation capability evaluation. This review suggested that one approach is not enough to gain the suitable quantity and yield of DNA for assessing microbial diversity, community structure and population dynamics, and that a careful attention has to be paid for selecting an optimal method for individual environmental purpose.

• Journal of Environmental Science International
• /
• v.23 no.3
• /
• pp.483-492
• /
• 2014

DNA damage such as genotoxicity was identified with comet assay, which blood cell of a marine parrot fish (Oplegnathus fasciatus) was exposed to an acidified seawater, lowered pH gradient making of $CO_2$ gas. The gradient of pH were 8.22, 8.03, 7.81, 7.55 with control as HBSS solution with pH 7.4. DNA tail moment of fish blood cell was $0.548{\pm}0.071$ exposed seawater of pH 8.22 condition, on the other hand, DNA tail moment $1.601{\pm}0.197$ exposed acidified seawater of pH 7.55 lowest condition. The approximate difference with level of DNA damage was 2.9 times between highest and lowest of pH. DNA damage with decreasing pH was significantly increased with DNA tail moment on blood cell of marine fish (ANOVA, p < 0.001). Ocean acidification, especially inducing the leakage of sequestered $CO_2$ in geological structure is a consequence from the burning of fossil fuels, and long term effects on marine habitats and organisms are not fully investigated. The physiological effects on adult fish species are even less known. This result shown that the potential of dissolved $CO_2$ in seawater was revealed to induce the toxic effect on genotoxicity such as DNA breakage.

• Environmental Mutagens and Carcinogens
• /
• v.9 no.1
• /
• pp.23-32
• /
• 1989

Chinese hamster ovary (CHO)-K1 cells echibited a differential sensitivity in the process of DNA repair synthesis induced by ethyl methanesulfonate (EMS) or bleomycin (BLM) in relation to cell cycle. Two assays were employed in this study: alkaline elution and unscheduled DNA synthesis. The post-treat-ment with aphidicolin (APC), an inhibitor of DNA polymerase alpha, inhibited DNA repair synthesis induced by EMS in G2 phase, while APC did not show any effect on BLM-induced DNA repair synthesis in all phases. On the other hands, the 2', 3'-dideoxythymidine (ddTTP), an inhibitor of DNA polymerase beta, inhibited DNA repair synthesis induced by EMS or BLM in both of G1 and G2 phases. These results suggested that the involvement of DNA polymerase alpha and beta in DNA repair was dependent on cell stage or used chemical agent.

• Environmental Mutagens and Carcinogens
• /
• v.19 no.1
• /
• pp.34-38
• /
• 1999

Fumonisin B1 is a secondary metabolite of Fusarium moniliforme, a contaminant of corn and corn product. Fumonisin B1 has been shown to be responsible for major toxicological effects of the fungus in rats, horses, and pigs. Fumonisin B1 induced λ DNA fragmentation, which was increased with incubation time, reducing agent NADPH and metal ion (Cu2+). The DNA damage was inhibited by dimethyl sulfoxide (DMSO) or mannitol as radical scavenger for free radicals. DNA fragmentation, induced by fumonisin B1 in the presence of 1 mM NADPH and 0.1 mM CuCl2, was inhibited by 100 mM DMSO. By the in vitro reaction of fumonisin B1 with supercoiled plasmid pBR322 DNA, plasmid DNA was relaxed, eventually linearized in the agarose gel electrphoresis. From rifampicin sensitive E. coli CSH138 in bacterial mutagenesis system, the rifampicin resistant E. coli mutants were obtained by fumonisin B1. These results suggest that fumonisin B1 may be a possible environmental mutagen in bacterial mutagen assay system.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.10 no.1
• /
• pp.95-110
• /
• 2015

Most innovation related theories including entrepreneurship theory regard the CEO's innovative competencies as the starting point of innovation. The study was investigated the relationship between CEO's innovation DNA and Innovation and the effects of environmental fit in their relation. For the empirical test, the sample was collected from 110 manufacturing companies in Daegu and Gyeongbook region. The results as follows: First, Innovation DNA has generally significant positive effect on innovation. The effect of discovery DNA is stronger than operating DNA to the product innovation, but the operating DNA stronger than the discovery DNA to the process innovation. The fit between CEO's innovative DNA and exogenous environmental turbulence make a strength innovation. The supplementary fit between discovery DNA and technology turbulence and complementary fit between discovery DNA and market turbulence reinforce product innovation. Process innovation were strengthen by the complementary fit between operating DNA and market turbulence.

• Journal of Korean Society on Water Environment
• /
• v.24 no.6
• /
• pp.817-822
• /
• 2008

In order to identify various Cryptosporidium species in environment, nested PCR-RFLP and DNA sequencing method were used. The sensitivity of nested PCR-RFLP based on 18s rRNA gene was shown to 1 oocyst. Therefore, we applied nested PCR-RFLP method to environmental samples. As a result, only 4 samples out of 8 samples confirmed as Cryptosporidium parvum by standard method of Cryptosporidium were identified as Cryptosporidium parvum by nested PCR-RFLP and DNA sequencing method. The rest of 4 samples among 8 samples were identified as Cryptosporidium muris, Cryptosporidium bailey. Therefore, in addition to standard method of Cryptosporidium, supplementary verification through nested PCR-RFLP and DNA sequencing should be needed to give more accurate information about risk of Cryptosporidium.

• Korean Journal of Medicinal Crop Science
• /
• v.23 no.6
• /
• pp.489-499
• /
• 2015

Background : Plants belonging to 5 species of the genus Eleutherococcus are currently distributed in the Korean peninsula. The traditional medicine 'Ogapi', derived from Eleutherococcus sessiliflorus and other related species, and 'Gasiogapi', derived from Eleutherococcus senticosus, are frequently mixed up and marketed. Therefore, accurated identification of their origins in urgently required. Methods and Results : Candidate genes from nuclear ribosomal DNA (nrDNA) and chloroplast DNA (cpDNA) of Eleutherococcus plants were analyzed. Whereas the nrDNA-internal transcribed spacer (ITS) regions were useful in elucidating the phylogenetic relationships among the plants, the cpDNA regions were not as effective. Therefore, a combined analysis with nrDNA-ITS was performed. Various combinations of nrDNA and matK were effective for discriminating among the plants. However, the matK and rpoC1 combination was ineffective for discriminating among some species. Based on these results, it was found that OG1, OG4, OG5, OG7, GS1, GS2, and GS3 were derived from E. sessiliflorus. In particular, it was confirmed that GS1, GS2, and GS3 were not derived from E. senticosus. However, more samples need to be analyzed because identification of the origins of OG2, OG3, OG6 and GS4 was not possible. Conclusion : The ITS2, ITS5a, and matK combination was the most effective in identifying the phylogenetic relationship among Eleutherococcus plants and traditional medicines based on Eleutherococcus.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.22 no.6
• /
• pp.125-138
• /
• 2019

This study aims to highlight the possibility in identifying species composition of fish communities using the environmental DNA (eDNA) metabarcoding technique, from both of the technical introduction and the pilot test at urban ecological streams. This new emerging survey technique using eDNA is getting popular in the world as a compensating way for the conventional field survey. However, the application to the domestic cases has yet to be studied. We attempted to use this technique for identifying fish species observed at four survey points in Hwangguji-chon, Suwon City. As a result, the detected number of species by eDNA sampled once in May was significantly matched with the total number of observed species in annual field surveys. Additionally eDNA results indicated the presence possibility of the unobserved species in field last year, even though the validation may be required. This survey technique seems to be more efficient and applicable to diverse situations of the fields and species, thereby needs to be studied further. We discussed the pros and cons of the application and summarized the research directions in future.

• Proceedings of the National Institute of Ecology of the Republic of Korea
• /
• v.3 no.1
• /
• pp.54-65
• /
• 2022

Species distribution models are a useful tool for predicting future distribution and establishing a preemptive response of invasive species. However, few studies considered the possibility of habitat for the aquatic organism and the number of target sites was relatively small compared to the area. Environmental DNA (eDNA) is the emerging tool as the methodology obtaining the bulk of species presence data with high detectability. Thus, this study applied eDNA survey results of Micropterus salmoides and Lepomis macrochirus to species distribution modeling by seasons in the Anyang stream network. Maximum Entropy (MaxEnt) model evaluated that both species extended potential distribution area in October compared to July from 89.1% (12,110,675 m²) to 99.3% (13,625,525 m²) for M. salmoides and 76.6% (10,407,350 m²) to 100% (13,724,225 m²) for L. macrochirus. The prediction value by streams was varied according to species and seasons. Also, models elucidate the significant environmental variables which affect the distribution by seasons and species. Our results identified the potential of eDNA methodology as a way to retrieve species data effectively and use data for building a model.