• 농업과학연구
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• 제48권3호
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• pp.505-514
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• 2021

Among non-timber forest products, Tricholoma matsutake is a high value added item. Many countries, including Korea, China, and Japan, are doing research and technology development to increase artificial cultivation and productivity. However, the production of T. matsutake is on the decline due to global warming, abnormal temperatures and pine tree pest problems. Therefore, it is necessary to identify trends in domestic and foreign research on T. matsutake, respond to preemptive research and development to preserve the genetic resources of T. matsutake and increase its productivity. Based on the correlation between keywords in the high frequency keywords, it was observed that microbial clusters of T. matsutake are mainly found in Korea. The main focus in China has been the pharmacology studies on the ingredients of T. matsutake. The main focus in Japan has been on preserving the genetic diversity and species of T. matsutake. Thus, future domestic studies of T. matsutake will require pharmacological studies on the ingredients of T. matsutake and on its genetic diversity and species conservation. In addition, unlike China and Japan, genetic keywords did not appear in Korea at high frequency. Therefore, Korea will have to proceed with research using modern molecular biology techniques.

• 한국환경복원기술학회지
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• 제27권2호
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• pp.29-42
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• 2024

As a global response to climate and biodiversity challenges, there is an emphasis on the conservation and restoration of ecosystems that can simultaneously reduce carbon emissions and enhance biodiversity. This study comprised a text analysis and keyword extraction of 1,100 research papers addressing nature restoration in Korea, aiming to provide a quantative and systematic evaluation of domestic research trends in this field. To discern the major research topics of these papers, topic modeling was applied and correlations were established through network analysis. Research on nature restoration exhibited a mainly upward trend in 2002-2022 but with a slight recent decline. The most common keywords were "species," "forest," and "water". Research topics were broadly classified into (1) predictions of habitat size and species distribution, (2) the conservation and utilization of natural resources in urban areas, (3) ecosystems and landscape managements in protected areas, (4) the planting and growth of vegetation, and (5) habitat formation methods. The number of studies on nature restoration are increasing across various domains in Korea, with each domain experiencing professional development.

• Journal of Ecology and Environment
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• 제48권2호
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• pp.144-151
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• 2024

Background: This study focused on the diet of Clithon retropictum, level II endangered species in Korea. Since the development of brackish water zones has led to a decline in the population of this species, to obtain information on the ecology of C. retropictum required for its conservation and restoration. To investigate the actual preys of C. retropictum in south coast of Korea, we conducted high-throughput sequencing and metabarcoding techniques to extract DNA from gut contents and periphyton in their habitats. Results: Total 118 taxonomic groups were detected from periphyton samples. 116 were Chromista and Cyanobacteria dominated in the most samples. In gut contents samples, 98 taxonomic groups were detected. Similar to the results of periphyton, 96 were Chromista and Cyanobacteria dominated in the most samples. In the principal component analysis based on the presence/absence of taxonomic groups, gut content composition showed more clustered patterns corresponding to their habitats. Bryophyta was the most crucial taxonomic group explaining the difference between periphyton and gut contents compositions of C. retropictum. Conclusions: Our finding suggests that C. retropictum may not randomly consume epilithic algae but instead, likely to supplement their diet with Bryophyta.

• 농업생명과학연구
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• 제46권4호
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• pp.21-30
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• 2012

본 연구는 요인분석을 통해 수종간의 관계 및 수종 구성에 영향을 미치는 요인 등을 파악하고, 군집분석을 이용하여 두타산 일대 천연림을 대상으로 산림유형을 분류하기 위해 수행되었다. 상관관계분석을 통해 주요 수종들의 상호관계를 나타내었고, 요인분석을 통해 수종구성에 영향을 미치는 세 가지 요인을 알아보았으며 요인점수를 바탕으로 군집분석을 실시하여 산림유형을 분류하였다. 마지막으로 분산분석을 실시하여 군집분석의 결과를 평가하였다. 수종간 상관관계분석 결과와 요인분석 결과는 밀접한 관련이 있는 것으로 나타났으며, 수종 구성에 미치는 첫 번째 요인은 산림천이과정에 의한 소나무의 쇠퇴현상이었다. 두 번째 요인과 세 번째 요인은 각각 계곡의 생육환경과 산복의 생육환경이었다. 두타산 일대 산림의 수종구성에 영향을 미치는 3가지 요인을 바탕으로 군집분석을 실시하여 산림유형을 분류하였고 분산분석을 통해 분류 결과를 검증한 결과, 총 4가지의 산림유형(신갈나무-고로쇠나무-물푸레나무군집, 신갈나무군집, 신갈나무-피나무군집, 소나무군집)으로 분류되었다.

• 생태와환경
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• 제56권3호
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• pp.229-241
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• 2023

멸종위기 야생생물 I급 종인 여울마자는 분포 및 개체수가 지속적으로 감소하여 현재는 낙동강수계 남강 및 일부 지류 하천에만 제한적으로 출현하고 있다. 절멸이 임박한 여울마자의 복원을 위해서는 감소원인 파악을 통한 적절한 계획 수립이 중요하지만 자료 및 연구 부족으로 인해 진행이 미흡한 상황이다. 따라서 본 연구에서는 여울마자에 분포지역을 대상으로 현장조사와 문헌조사를 통해 현재출현지역과 과거출현지역의 이화학적, 생물학적, 사회학적 서식환경에 대한 차이를 분석하였다. 현장조사 결과 현재출현지점과 과거출현지점에 전기전도도에 차이가 있었으며, 동서종 군집 또한 차이가 있는 것으로 확인되었다. 문헌 연구자료를 활용한 분석에서도 전반적으로 과거 출현지점들의 이화학적 환경이 양호하지 않은 것으로 나타났으며, 이로 인해 영향을 받은 생물학적 요인의 부정적 결과가 유발되었다. 특히, 도시화로 인한 영향이 여울마자 서식환경에 주요한 영향을 주고 있는 것으로 파악되었다. 멸종위기종인 여울마자의 복원을 위해서는 서식지의 안정화가 중요하다. 과거 서식하던 지역들에서는 하천 공사, 보 건설과 같은 교란이 하천을 물리적, 이화학적으로 변화시키면서 여울마자에 영향을 주었기 때문에 향후 여울마자의 서식지 관리 및 복원을 위해서는 하천의 연결성 회복 및 이화학적 환경을 함께 고려한 종합적인 계획인 필요한 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제2권4호
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• pp.293-296
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• 1992

Increased concentrations of yeast extract led to increased growth yields and faster growth rates of the newly isolated Clostridium thermobutyricum. This species produced butyrate as its main fermentation product from glucose as well as from yeast extract. In the presence of peptone or tyrptone and during growth on agar, up to 70% of the cells sporulated. Growth yields were 30 and 55 g per mole glucose in the presence of 0.05 and 2.0% yeast extract, respectively. The Arrhenius graph was biphasic, exhibiting an intermediary plateau around $38^{\circ}C$ with a concomitant change in the Arrhenius energy. The optimum temperature was $55^{\circ}C$. An unusually sharp decline in the growth rate occurred above $59^{\circ}C$ .

• 한국균학회지
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• 제46권3호
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• pp.205-211
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• 2018

Fungal endophytes are defined as fungi inhabiting plant tissues, causing no apparent disease. As the agricultural and ecological importance of endophytes has increased, many studies have been performed on various aspects, ranging from basic identification, taxonomy, and evolution to secondary metabolites with potential for human use. In the Korean Peninsula, conifers are the most commonly found evergreen trees, with approximately 30 to 60 reported taxa. Studies on the effect of conifer-associated endophytes on the host plants are required for the preservation and conservation of coniferous forests which decline by climate change and deforestation. This review summarizes the diversity of endophytic fungi in coniferous trees of Korea and their relationship with host plants.

• Journal of Applied Biological Chemistry
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• 제42권2호
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• pp.57-61
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• 1999

Seven numerically dominant 2-methyl-4-chlorophenoxyacetic acid (MCPA)-degrading bacteria were isolated from agricultural soils. The isolates utilized the herbicide MCPA as a sole carbon source, producing significant biomass in MCPA mineral medium. They exhibited diverse herbicide degradation capabilities, but most of them grew very slowly in mineral medium containing herbicide. The chromosomal DNA patterns of the isolates obtained by polymerase chain reaction amplification of repetitive extragenic palindromic sequences were distinct from each other. One isolate, SH3, which was identified as Sphingomonas species by fatty acid methyl ester analysis, was able to degrade 5 different phenoxyacetic acid herbicides within 4 days. This strain contains two plasmids, and the smaller one has a crucial role in herbicide degradation. MCPA treated into agricultural soils without indigenous MCPA-degraders persisted for a long time, but the application of the isolate SH3 resulted in rapid decline of MCPA concentration in the soil.

• Toxicological Research
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• 제25권1호
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• pp.9-15
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• 2009

Historically, research in toxicology has utilized non-human mammalian species, particularly rats and mice, to study in vivo the effects of toxic exposure on physiology and behavior. However, ethical considerations and the overwhelming increase in the number of chemicals to be screened has led to a shift away from in vivo work. The decline in in vivo experimentation has been accompanied by an increase in alternative methods for detecting and predicting detrimental effects: in vitro experimentation and in silico modeling. Yet, these new methodologies can not replace the need for in vivo work on animal physiology and behavior. The development of new, non-mammalian model systems shows great promise in restoring our ability to use behavioral endpoints in toxicological testing. Of these systems, the zebrafish, Danio rerio, is the model organism for which we are accumulating enough knowledge in vivo, in vitro, and in silico to enable us to develop a comprehensive, high-throughput toxicology screening system.

• BMB Reports
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• 제54권5호
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• pp.253-259
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• 2021

Aging is characterized by a functional decline in most physiological processes, including alterations in cellular metabolism and defense mechanisms. Increasing evidence suggests that caloric restriction extends longevity and retards age-related diseases at least in part by reducing metabolic rate and oxidative stress in a variety of species, including yeast, worms, flies, and mice. Moreover, recent studies in invertebrates - worms and flies, highlight the intricate interrelation between reproductive longevity and somatic aging (known as disposable soma theory of aging), which appears to be conserved in vertebrates. This review is specifically focused on how the reproductive system modulates somatic aging and vice versa in genetic model systems. Since many signaling pathways governing the aging process are evolutionarily conserved, similar mechanisms may be involved in controlling soma and reproductive aging in vertebrates.