• Journal of Applied Biological Chemistry
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• 제58권4호
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• pp.369-375
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• 2015

Meat from black pigs (BP) is in high demand compared with that from modern white pig (WP) breeds such as Landrace pigs owing to its high quality. However, the growth rate of black pigs is slower than that of white pig breeds. We investigated differences in the fecal microbial composition between white and black pigs to explore whether these breeds differed in the composition of their gut microbial communities. The swine gut microbiota was investigated using Illumina's MiSeq-based sequencing technology by targeting the V4 region of the 16S rRNA gene. Our results showed that the composition of the gut microbiota was significantly different between the two pig breeds. While the composition of the WP microbiota shifted according to the growth stage, fewer shifts in composition were observed for the BP gut microbiota. In addition, the WP gut microbiota showed a higher Firmicutes/Bacteroidetes ratio compared with that of BP. A high ratio between these phyla was previously reported as an obesity-linked microbiota composition. Moreover, the WP microbiota contained a significantly higher abundance of cellulolytic bacteria, suggesting a possibility of higher fiber digestion efficiency in WP compared to BP. These findings may be important factors affecting growth performance and energy-harvesting capacities in pigs. Our findings of differences in the gut microbiota composition between the two breeds may provide new leads to understand growth rate variation across pig breeds.

• The Plant Pathology Journal
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• 제33권6호
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• pp.529-542
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• 2017

Control of plant diseases is largely dependent on use of agrochemicals. However, there are widening gaps between our knowledge on plant diseases gained from genetic/mechanistic studies and rapid translation of the knowledge into target-oriented development of effective agrochemicals. Here we propose that the time is ripe for computer-aided drug discovery/design (CADD) in molecular plant pathology. CADD has played a pivotal role in development of medically important molecules over the last three decades. Now, explosive increase in information on genome sequences and three dimensional structures of biological molecules, in combination with advances in computational and informational technologies, opens up exciting possibilities for application of CADD in discovery and development of agrochemicals. In this review, we outline two categories of the drug discovery strategies: structure- and ligand-based CADD, and relevant computational approaches that are being employed in modern drug discovery. In order to help readers to dive into CADD, we explain concepts of homology modelling, molecular docking, virtual screening, and de novo ligand design in structure-based CADD, and pharmacophore modelling, ligand-based virtual screening, quantitative structure activity relationship modelling and de novo ligand design for ligand-based CADD. We also provide the important resources available to carry out CADD. Finally, we present a case study showing how CADD approach can be implemented in reality for identification of potent chemical compounds against the important plant pathogens, Pseudomonas syringae and Colletotrichum gloeosporioides.

• 한국해양바이오학회지
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• 제3권1호
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• pp.31-37
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• 2008

Off the 1,572 km long coastline of Namibia lies known as the Benguela upwelling system, a very rich source of marine life supporting traditional and modern forms of fishery. Commercial fishing and fish processing is one of the fastest-growing sectors of the Namibian economy in terms of employment, export earnings, and contribution to GDP. The fishing industry has grown to the extent that it is currently Namibia's second biggest export earner of foreign currency after mining (90% of national output is marketed for export). In 2005, Namibia harvested about 552,164 tonnes of fish. The final value of processed products (export value) that year was around US$ 376.0 million. Besides the marine captured fisheries, Namibia also has a small but vibrant aquaculture sector. Inland captured fisheries exist in the north-east and north-west of Namibia where as commercial freshwater aquaculture of tilapia and catfish is also undertaken. The inland fisheries are mainly subsistence based and typically labour intensive, with low catch per unit effort. However the subsistence fisheries from these regions play a significant role in the lives of rural community. The domestic market for marine fish products is extremely limited due to the small size of the population (2 million). The fishing industry is a source of considerable employment for many Namibians. Huge potential to increase production exists in Namibia, unpolluted high quality marine waters, high natural primary productivity of the seawater, availability of inexpensive fish by-products from established fish processing sector for inclusion in wet aqua-feeds and well-established processing, packaging and marketing systems due to the marine capture fisheries that can be adopted for aquaculture purpose.

• Journal of Microbiology and Biotechnology
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• 제33권6호
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• pp.760-770
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• 2023

Continuous cropping obstacles have become a serious factor restricting sustainable development in modern agriculture, while companion planting is one of the most common and effective methods for solving this problem. Here, we monitored the effects of companion planting on soil fertility and the microbial community distribution pattern in pepper monoculture and companion plantings. Soil microbial communities were analyzed using high-throughput sequencing technology. Companion plants included garlic (T1), oat (T2), cabbage (T3), celery (T4), and white clover (T5). The results showed that compared with the monoculture system, companion planting significantly increased the activities of soil urease (except for T5) and sucrase, but decreased catalase activity. In addition, T2 significantly improved microbial diversity (Shannon index) while T1 resulted in a decrease of bacterial OTUs and an increase of fungal OTUs. Companion planting also significantly changed soil microbial community structures and compositions. Correlation analysis showed that soil enzyme activities were closely correlated with bacterial and fungal community structures. Moreover, the companion system weakened the complexity of microbial networks. These findings indicated that companion plants can provide nutrition to microbes and weaken the competition among them, which offers a theoretical basis and data for further research into methods for reducing continuous cropping obstacles in agriculture.

• 한국가금학회지
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• 제44권4호
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• pp.245-251
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• 2017

A dose-response experiment was conducted to determine the lysine requirement for broiler breeder hens during pre-peak production. Totally, one hundred and twenty-six flock 23-week-old Ross 308 broiler breeder hens with similar body weight were selected ($2,188{\pm}32g$) for a 6-week experiment. Hens were fed with a basal diet of corn-wheat-soybean meal formulated to achieve the Ross 308 breeder nutrient specifications (2016), except for lysine. The 7 graded, daily lysine intake levels used in this experiment were 732, 785, 838, 891, 944, 997, and 1,050 mg, and hens were restricted to 133 g of feed throughout this experiment. Pen based egg production were recorded once a day and all eggs were weighed daily. Age at sexual maturity was determined when the hens attained age at 25% production. Body weight at 23~29 weeks of age was not affected (P>0.05) by lysine levels. By fitting a linear-plateau model, the daily lysine requirements for feed conversion ratio, total produced egg weight, and age at sexual maturity at 23~29 weeks of age were estimated as 865, 907, and 891 mg, respectively. Using a quadratic-plateau model, the daily lysine requirement at 23~29 weeks of age were estimated as 974, 964, and 950 mg for feed conversion ratio, total produced egg weight, and age at sexual maturity, respectively. These results suggested that the daily lysine requirement for modern broiler breeder hens according to the National Research Council (1994) are insufficient for higher total produced egg weight, sexual maturity, and feed efficiency, and 120% of the NRC recommendation level would improve hen productivity when data are fitted under linear- and quadratic-plateau models.

• 한국미생물·생명공학회지
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• 제31권2호
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• pp.95-102
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• 2003

미세포류는 다양한 서식환경, 분류군, 종조성 등의 특징을 갖는 미생물군이며 , 이들은 각종 유용물질을 생산하는 것으로 알려지고 있다. 따라서 지금까지 유용물질 생산을 위하여 집중적으로 연구되었던 세균, 곰팡이 등과 함께 미래의 유용한 물질생산의 보고로 간주되고 있다. 미세조류 배양의 가장 큰 장점은 대부분의 작물생산에 적합하지 않는 높은 염도, 강한 알카리 등의 극한 환경에서도 성장하는 조류가 있다는 점이다. 최근 유용 미생물 탐색, 미생물 배양, 유용물질 탐색기술 등의 기반 기술이 크게 발달하면서 미세조류 배양 및 물질생산 비용은 점차 저렴해지고 있다. 또한 최근 급격히 발달된 생명공학기술을 이용한 유전공학적 조류주 개량 등으로 유용물질 생산 효율도 크게 증가시킬 수 있게 되었다. 한편 전 세계적으로 지구환경문제가 중요 쟁점으로 등장하였으며, 동시에 생물다양성협약 등 생물자원의 보존 및 확보가 무엇보다도 중요한 시점이라 할 수 있다. 미세조류의 대량배양 시 배지로서 축산폐수를 이용한다면 유용물질의 생산과 동시에 폐수의 고차처리, 대기 중 이산화탄소의 고정화 등 당면한 환경문제를 해결할 수 있는 환경친화적 기술로 평가되고 있다. 따라서 미세조류의 대량배양을 통하여 biomass로부터 건강보조식품, 천연색소, 의약용 물질 등의 고부가 유용물질을 생산하여 경제적 가치를 창출할 수 있다. 또한 미세조류의 대량배양은 부수적으로 생물학적 이산화탄소 고정화를 통한 대기 중 농도감소 등의 지구환경문제의 해결에도 기여할 수 있다. 즉, microalgal biotechnolog는 생물산업의 활성화와 함께 횐경산업의 발전을 도모할 수 있는 유망한 미래 산업으로서 앞으로 큰 발전이 기대된다. 수 있음을 보인다.옥천비변성대의 고생대 지층에서도 보고된 바 있기 때문에 옥천대에 광역적으로 일어난 것으로 생각된다.didn′t have purchase intention of apparel on Internet shopping malls were summarized and labeled as: difficulty of decision making due to virtual shopping environment, insufficiency of diverse apparels, users′ unease handling, risk of incredible apparel quality, unfamiliarity of Internet shopping and risks of unsecurity. Difficulty of decision making due to virtual shopping environment was determined as the most important factor of reasons that respondents didn′t have purchase intention of apparels in website.previous experience" in both cases. The rural housewives bought clothes when they had any "event" and urban housewives bought them when they had "extra money or sale".ng about the real environmental damage of the vehicles. In the paper we describe "how should the

• 한국미생물·생명공학회지
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• 제29권1호
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• pp.1-11
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• 2001

Lactic acid bacteria (LAB) are widely used for various food fermentation. With the recent advances in modern biotechnology, a variety of bio-products with the high economic values have been produced using microorganisms. For molecular cloning and expression studies on the gene of interest, E. coli has been widely used mainly because vector systems are fully developed. Most plasmid vectors currently used for E, coli carry antibiotic-resistant markers. As it is generally believed that the antibiotic resistance markers are potentially transferred to other bacteria, application of the plasmid vectors carrying antibiotic resistance genes as selection markers should be avoided, especially for human consump-tion. By contrast, as LAB have some desirable traits such that the they are GRAS(generally recognized as safe), able to secrete gene products out of cell, and their low protease activities, they are regarded as an ideal organism for the genetic manipulation, including cloning and expression of homologous and heterologous genes. However, the vec-tor systems established for LAB are stil insufficient to over-produce gene products, stably, limiting the use of these organisms for industrial applications. For a past decade, the two popular plasmid vectors, pAM$\beta$1 of Streptococcus faecalis and pGK12 theB. subtilis-E. coli shuttle vector derived from pWV01 of Lactococcus lactis ssp. cremoris wg 2, were most widely used to construct efficient chimeric vectors to be stably maintained in many industrial strains of LAB. Currently, non-antibiotic markers such as nisin resistance($Nis^{r}$ ) are explored for selecting recombi-nant clone. In addition, a gene encoding S-layer protein, slp/A, on bacterial cell wall was successfully recombined with the proper LAB vectors LAB vectors for excretion of the heterologous gene product from LAB Many food-grade host vec-tor systems were successfully developed, which allowed stable integration of multiple plasmid copies in the vec-mosome of LAB. More recently, an integration vector system based on the site-specific integration apparatus of temperate lactococcal bacteriophage, containing the integrase gene(int) and phage attachment site(attP), was pub-lished. In conclusion, when various vector system, which are maintain stably and expressed strongly in LAB, are developed, lost of such food products as enzymes, pharmaceuticals, bioactive food ingredients for human consump-tion would be produced at a full scale in LAB.

• 한국산림과학회지
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• 제85권4호
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• pp.667-679
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• 1996

최근에 임목의 영양번식체계나 우량묘목을 양성하기 위하여 임목의 체세포배를 이용해서 "인공종자" 형태로 보관하거나 연속배양기를 사용하여 계속적으로 체세포배를 생산하는 방법은 매우 중요한 기법에 속한다. 이러한 체세포 배양기법은 임목의 생물공학 뿐만아니라 체세포배 발생학, 세포 및 분자생물학 연구에 있어서 중요한 역할을 한다. 현재 침엽수 체세포 배양에 대한 복잡한 기작이 많이 밝혀지고 있으나 이러한 기초적 지식이 현실적으로 잘 응용되지 못하는 점이 임목생물공학의 발전을 저해하는 요소로 지적되고 있다. 본 총설에서는 이러한 기초적 지식을 침엽수 체세포배 배양의 응용적 연구에 이용하는데 초점을 맞추었다.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.442-455
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• 2010

식물공장 (plant factory)은 파종에서 재배 및 수확까지 실내에서 종합적으로 관리 제어되는 공장식 식물생산기술로 현대농업의 결정체이다. 식물공장은 청결한 환경에서 안전성 높은 농산물을 연중 생산할 수 있고, 작업환경이 좋아 노동력 확보가 수월하다. 선진국들은 수 십년 전부터 식물공장의 산업적 경제적 효과를 예측하고 이 분야에 많은 관심을 가지고 적극적으로 투자해 왔다. 최근 우리나라도 우수한 기술력과 인력을 적극 활용하여 국제 경쟁력이 있는 식물공장 시스템을 개발하고자 활발히 연구개발을 진행하고 있다. 식물공장은 초기투자비용의 과다, 전용 품종의 재배기술 부족, 운영비 절감 등의 문제점이 아직 해결되지 않아 기존 농업과 경쟁하기 어렵다. 그러나 식물생명공학 분야의 전문가들이 식물공장 시스템 개발에 적극 참여한다면 여러 문제점이 개선될 것이다. 환경변화에 의한 농작물 경작의 어려움에 당면하고 있는 농촌과 농업에 식물공장을 잘 활용한다면 농산물 경작의 문제점을 해결하고, 식량문제와 환경문제를 해결하는데 큰 역할을 할 수 있을 것이다.

• ALGAE
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• 제37권2호
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• pp.105-121
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• 2022

Modern seaweed farming relies heavily on seedlings from natural beds or vegetative cuttings from previous harvests. However, this farming method has some disadvantages, such as physiological variation in the seed stock and decreased genetic variability, which reduces the growth rate, carrageenan yield, and gel strength of the seaweeds. A new method of seedling production that is sustainable, scalable, and produces a large number of high-quality plantlets is needed to support the seaweed farming industry. Recent use of tissue culture and micropropagation techniques in eucheumatoid seaweed production has yielded promising results in increasing seed supply and growing uniform seedlings in large numbers in a shorter time. Several seaweed species have been successfully cultured and regenerated into new plantlets in laboratories using direct regeneration, callus culture, and protoplast culture. The use of biostimulants and plant growth regulators in culture media increases the seedling quality even further. Seedlings produced by micropropagation grew faster and had better biochemical properties than conventionally cultivated seedlings. Before being transferred to a land-based grow-out system or ocean nets for farming, tissue-cultured seedlings were recommended to undergo an acclimatization process to increase their survival rate. Regular monitoring is needed to prevent disease and pest infestations and grazing by herbivorous fish and turtles during the farming process. The current review discusses recent techniques for producing eucheumatoid and other valuable seaweed farming materials, emphasizing the efficiency of micropropagation and the transition from laboratory culture to cultivation in land-based or open-sea grow-out systems to elucidate optimal conditions for sustainable seaweed production.