• 한국축산식품학회지
• /
• 제38권6호
• /
• pp.1144-1154
• /
• 2018

Both the calcium and collagen in bone powder are hard to be absorbed by the body. Although enzymatic hydrolysis by protease increased the bio-availability of bone powder, it was a meaningful try to further increase $Ca^{2+}$ release, oligopeptide formation and antioxidant activity of the sheep bone hydrolysate (SBH) by lactic acid bacteria (LAB) fermentation. Lactobacillus helveticus was selected as the starter for its highest protease-producing ability among 5 tested LAB strains. The content of liberated $Ca^{2+}$ was measured as the responsive value in the response surface methodology (RSM) for optimizing the fermenting parameters. When SBH (adjusted to pH 6.1) supplemented with 1.0% glucose was inoculated 3.0% L. helveticus and incubated for 29.4 h at $36^{\circ}C$, $Ca^{2+}$ content in the fermented SBH significantly increased (p<0.01), and so did the degree of hydrolysis and the obtaining rate of oligopeptide. The viable counts of L. helveticus reached to $1.1{\times}10^{10}CFU/mL$. Results of Pearson correlation analysis demonstrated that LAB viable counts, $Ca^{2+}$ levels, obtaining rates of oligopeptide and the yield of polypeptide were positively correlated with each other (p<0.01). The abilities of SBH to scavenge the free radicals of DPPH, OH and ABTS were also markedly enhanced after fermentation. In conclusion, L. helveticus fermentation can further boost the release of free $Ca^{2+}$ and oligopeptide, enhance the antioxidant ability of SBH. The L. helveticus fermented SBH can be developed as a novel functional dietary supplement product.

• Geomechanics and Engineering
• /
• 제17권4호
• /
• pp.367-374
• /
• 2019

This study concluded the results of a research on the features of cement based permeation grout, based on some important grout parameters, such as the rheological properties (yield stress and viscosity), coefficient of permeability to grout ($k_G$) and the inject ability of cement grout (N and $N_c$ assessment), which govern the performance of cement based permeation grouting in porous media. Due to the limited knowledge of these important grout parameters and other influencing factors (filtration pressure, rate and time of injection and the grout volume) used in the field work, the application of cement based permeation grouting is still largely a trial and error process in the current practice, especially in the local construction industry. It is seen possible to use simple formulas in order to select the injection parameters and to evaluate their inter-relationship, as well as to optimize injection spacing and times with respect to injection source dimensions and in-situ permeability. The validity of spherical and cylindrical flow model was not verified by any past research works covered in the literature review. Therefore, a theoretical investigation including grout flow models and significant grout parameters for the design of permeation grouting was conducted in this study. This two grout flow models were applied for three grout mixes prepared for w/c=0.75, w/c=1.00 and w/c=1.25 in this study. The relations between injection times, radius, pump pressure and flow rate for both flow models were investigated and the results were presented. Furthermore, in order to investigate these two flow model, some rheological properties of the grout mixes, particle size distribution of the cement used in this study and some geotechnical properties of the sand used in this work were defined and presented.

• Journal of Microbiology and Biotechnology
• /
• 제31권8호
• /
• pp.1154-1162
• /
• 2021

The transcriptional capacities of target genes are strongly influenced by promoters, whereas few studies have focused on the development of robust, high-performance and cross-species promoters for wide application in different bacteria. In this work, four novel promoters (P_k.rtufB, P_k.r1, P_k.r2, and P_k.r3) were predicted from Ketogulonicigenium robustum and their inconsistency in the -10 and -35 region nucleotide sequences indicated they were different promoters. Their activities were evaluated by using green fluorescent protein (gfp) as a reporter in different species of bacteria, including K. vulgare SPU B805, Pseudomonas putida KT2440, Paracoccus denitrificans PD1222, Bacillus licheniformis and Raoultella ornithinolytica, due to their importance in metabolic engineering. Our results showed that the four promoters had different activities, with P_k.r1 showing the strongest activity in almost all of the experimental bacteria. By comparison with the commonly used promoters of E. coli (tufB, lac, lacUV5), K. vulgare (Psdh, Psndh) and P. putida KT2440 (JE111411), the four promoters showed significant differences due to only 12.62% nucleotide similarities, and relatively higher ability in regulating target gene expression. Further validation experiments confirmed their ability in initiating the target minCD cassette because of the shape changes under the promoter regulation. The overexpression of sorbose dehydrogenase and cytochrome c551 by P_k.r1 and P_k.r2 resulted in a 22.75% enhancement of 2-KGA yield, indicating their potential for practical application in metabolic engineering. This study demonstrates an example of applying bioinformatics to find new biological components for gene operation and provides four novel promoters with broad suitability, which enriches the usable range of promoters to realize accurate regulation in different genetic backgrounds.

• Journal of Periodontal and Implant Science
• /
• 제52권6호
• /
• pp.437-454
• /
• 2022

Embryonic stem cells have been a popular research topic in regenerative medicine owing to their pluripotency and applicability. However, due to the difficulty in harvesting them and their low yield efficiency, advanced cell reprogramming technology has been introduced as an alternative. Dental stem cells have entered the spotlight due to their regenerative potential and their ability to be obtained from biological waste generated after dental treatment. Cell reprogramming, a process of reverting mature somatic cells into stem cells, and transdifferentiation, a direct conversion between different cell types without induction of a pluripotent state, have helped overcome the shortcomings of stem cells and raised interest in their regenerative potential. Furthermore, the potential of these cells to return to their original cell types due to their epigenetic memory has reinforced the need to control the epigenetic background for successful management of cellular differentiation. Herein, we discuss all available sources of dental stem cells, the procedures used to obtain these cells, and their ability to differentiate into the desired cells. We also introduce the concepts of cell reprogramming and transdifferentiation in terms of genetics and epigenetics, including DNA methylation, histone modification, and non-coding RNA. Finally, we discuss a novel therapeutic avenue for using dental-derived cells as stem cells, and explain cell reprogramming and transdifferentiation, which are used in regenerative medicine and tissue engineering.

• Geomechanics and Engineering
• /
• 제36권6호
• /
• pp.601-618
• /
• 2024

The joint probability distribution of uncertain geomechanical parameters of geotechnical strata is a crucial aspect in constructing the reliability functional function for roof structures. However, due to the limited number of on-site exploration and test data samples, it is challenging to conduct a scientifically reliable analysis of roof geotechnical strata. This study proposes a Copula method based on small sample exploration and test data to construct the intensity characteristics of roof geotechnical strata. Firstly, the theory of multidimensional copula is systematically introduced, especially the construction of four-dimensional Gaussian copula. Secondly, data from measurements of 176 groups of geomechanical parameters of roof geotechnical strata in 31 coal mines in China are collected. The goodness of fit and simulation error of the four-dimensional Gaussian Copula constructed using the Pearson method, Kendall method, and Spearman methods are analyzed. Finally, the fitting effects of positive and negative correlation coefficients under different copula functions are discussed respectively. The results demonstrate that the established multidimensional Gaussian Copula joint distribution model can scientifically represent the uncertainty of geomechanical parameters in roof geotechnical strata. It provides an important theoretical basis for the study of reliability functional functions for roof structures. Different construction methods for multidimensional Gaussian Copula yield varying simulation effects. The Kendall method exhibits the best fit in constructing correlations of geotechnical parameters. For the bivariate Copula fitting ability of uncertain parameters in roof geotechnical strata, when the correlation is strong, Gaussian Copula demonstrates the best fit, and other Copula functions also show remarkable fitting ability in the region of fixed correlation parameters. The research results can offer valuable reference for the stability analysis of roof geotechnical engineering.

• 한국자원식물학회지
• /
• 제27권5호
• /
• pp.556-566
• /
• 2014

연구에서는 사료자원 등 산업소재 사용분야가 넓고 $CO_2$ 흡수율이 일반작물의 5배 이상 되는 대표적 환경정화 식물로서 국내 활성화 가능성이 커지고 있는 케나프의 국내 도입 가능성을 확인하기 위하여 미국 등 10개국 유래 자원 29종을 수집하고 생태형 생육특성 수량과 사료가치 등을 비교 분석하였다. 수집자원은 개화시기에 따라 7월 상순에 개화하는 조생종과 8월 하순에서 9월 상순에 개화하는 중만생종 그리고 10월 하순에 개화하는 만생종으로 나누어졌는데 조생종은 국내 채종이 가능하나 수량이 떨어졌고(평균 7,895 kg/10a), 만생종은 수량은 높으나(평균 12,572 kg/10a) 국내에서 종자 결실이 되지 않았으며, 중만생종은 일정수준 이상의 수량(평균수량 11,207 kg/10a)이 확보되고 종자 결실이 가능하였다. 자원별로는 중국 수집종인 K12 (Hongma 300)와 인도 수집종 K25, 러시아 수집종 K22 그리고 중국 수집품종인 K21 (Khon kaen 60)이 10a당 13,500 kg 이상의 다수성 자원이었다. 수집자원별 사료가치 측정에서는 전체적으로 조생종이 우수하였으나 만생종 자원 중 다수성 자원인 K12, K21, K22 등은 가소화건물량(DDM)과 총가소화양분(TDN) 함량도 조생종보다도 높아 사료가치 항목을 종합하여 비교한 상대적 사료가치(RFV)가 K12는 102.5 K21은 116.2, K22는 120.2로 우수 자원으로 평가할 수 있었다. 그리고 우리나라 육성 품종인 'Jangdae'는 10a당 10,975 kg으로 수량과 12.5%의 조단백질함량 그리고 101.9의 상대적 사료가치(RFV) 등을 보이고 있어 수량성이 떨어지는 조생종 자원과 국내 종자결실이 불가능한 만생종 자원의 단점을 상호보완 할 수 있는 자원으로 금후에는 이러한 중만생종 자원의 수집과 선발에 좀 더 힘을 기울여야 할 것으로 보인다.

• Journal of Microbiology and Biotechnology
• /
• 제27권12호
• /
• pp.2156-2164
• /
• 2017

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered as an antitumor agent owing to its ability to induce apoptosis of cancer cells without imparting toxicity toward most normal cells. TRAIL is produced in poor yield because of its insoluble expression in the cytoplasm of E. coli. In this study, we achieved soluble expression of TRAIL by fusing maltose-binding protein (MBP), b'a' domain of protein disulfide isomerase (PDIb'a'), or protein disulfide isomerase at the N-terminus of TRAIL. The TRAIL was purified using subsequent immobilized metal affinity chromatography and amylose-binding chromatography, with the tag removal using tobacco etch virus protease. Approximately 4.5 mg of pure TRAIL was produced from 125 ml flask culture with a purification yield of 71.6%. The endotoxin level of the final product was $0.4EU/{\mu}g$, as measured by the Limulus amebocyte lysate endotoxin assay. The purified TRAIL was validated and shown to cause apoptosis of HeLa cells with an $EC_{50}$ and Hill coefficient of $0.6{{\pm}}0.03nM$ and $2.41{\pm}0.15$, respectively. The high level of apoptosis in HeLa cells following administration of purified TRAIL indicates the significance and novelty of this method for producing high-grade and high-yield TRAIL.

• Journal of the Korean Wood Science and Technology
• /
• 제13권3호
• /
• pp.41-48
• /
• 1985

In near future about 500,000 hectares of Japanese larch and pitch pine need thinning to improve crop-tree spacing and reasonable species composition in Korea. Although thinned trees show very little high quality wood, in fact, all the sawed products are suitable for construction and farming materials. Studies on the utilization of thinned small-diameter trees have been implemented in order to increase lumber yield and display the skeleton of farm buildings. The results obtained in this study were summarized as follows: 1. According to Korean Conifers Log Grading System, log grade 3 was 87.4 percent in Japanese larch bolts and 95.8 percent in pitch pine bolts from thinned trees. The ability to identify defects was essential for grading logs. 2. Cutting diagrams of sawing were developed for 1-sided sawing, 2-sided sawing and 3-sided sawing by small end diameter class of bolt and cutting sizes also were found to use effectively lumber with wane. 3. Lumber recovery of Pitch pine was a little higher than that of Japanese larch. The maximum lumber yields of pitch pine by sawing patterns were 87.2 percent for 1-sided sawing, 80.8 percent for 2-sided sawing an 64.1 percent for 3-sided sawing, up yield compared with 58.1 percent for 4-sided sawing. The lumber yield of 1, 2 and 3-sided sawing significantly was higher value than that of 4-sided sawing. 4. Lumber was inspected and graded. Lumber quality of diameter class 12cm was a little better than that of diameter class 8cm, but 90 percent of lumber in diameter c1ass 16cm fell into grade 3. The lumber grade was classified by Korean standard grades of confiers lumber. 5. Lumber from 1, 2 and 3-sided sawing was used to build the skeleton of a farm house ($53m^2$) and greenhouse ($60m^2$) in order to display more efficient use of small diameter trees from thinning 6. Total volume of timber for building a farm house was $8.1m^3$ of imported timber. Timber of $7m^3$, 70 percent of total volume would be substituted imported timber for domestic timber.

• Current Research on Agriculture and Life Sciences
• /
• 제6권
• /
• pp.105-112
• /
• 1988

질소원(窒素源)을 달리한 비료시용(肥料施用)이 대두(大豆)의 생육(生育), 수량(收量), 영양성분(營養成分) 및 단백질(蛋白質) 소화율(消化率) 등(等)에 미치는 비효(肥效)는 다음과 같다. 대두(大豆)의 생육상황(生育狀況)은 시비조건간(施肥條件間)에 대체로 유사(類似)하였으나 유안구(硫安區)와 무질소구(無窒素區)에 있어서 절수(節數)가 적었다. 근류수(根瘤數)와 무게는 유안구(硫安區)와 무질소구(無窒素區)가 낮았고 그 밖의 처리구(處理區)에 있어서는 차이가 보이지 않았다. 근류수(根瘤數) 당(當) 질소고정력(窒素固定力)은 생육초기(生育初期)와 개화기(開花期)에는 거의 비슷하였으나 pod 신장기(伸長期)에서는 개발복비구(開發複肥區)가 타처리구(他處理區)보다 비교적 높았다. 대두(大豆)의 100립중(粒重) 및 10a 당(當) 수량(收量)은 개발복비구(開發複肥區)가 타처리구(他處理區)보다 높았고 무질소구(無窒素區)는 질소원(窒素源) 비료(肥料)의 시용구(施用區)보다 대체로 낮았다. 또한 대두(大豆)의 조단백질(粗蛋白質) 함량은 질소원(窒素源) 비료(肥料)의 시용구(施用區)가 무질소구(無窒素區)에 비해 높았고 조지방(粗脂肪) 함량은 오히려 낮았다. 조회분(粗灰分) 함량은 시용구간(施用區間)에 대체로 비슷하였으나 조섬유(粗纖維) 함량은 기존복비구(旣存複肥區)가 타처리구(他處理區)에 비해 높았다. Ca, P, Na, K, Mg, Zn, Mn 및 Cu 함량은 시비조건간(施肥條件間)에 대체로 비슷하였으나 Fe 함량은 무질소구(無窒素區)가 질소원(窒素源) 비료(肥料)의 시용구(施用區)에 비(比)해 월등히 낮았으며, 단백질(蛋白質) 소화율(消化率)은 무질소구(無窒素區)에서 가장 높았다.

• 한국토양비료학회지
• /
• 제43권4호
• /
• pp.514-521
• /
• 2010

지속가능한 친환경농업을 위해서는 비료와 함께 식물생장촉진 미생물 또는 생장조절물질을 적절히 혼합 사용하는 것이 바람직하다. 본 연구에서는 Methylobacterium oryzae CBMB20의 근권토양접종과 메탄올 엽면살포에 따른 고추의 생육촉진 효과를 유기질 비료의 시용 수준별로 조사하였다. M. oryzae CBMB20의 근권토양접종과 메탄올 엽면살포는 각기 고추생육을 증대시켰다. 또한 이들을 동시에 혼합 처리하였을 경우에는 고추의 생장촉진 효과가 더욱 현저하게 나타났다. M. oryzae CBMB20의 근권토양접종과 메탄올 엽면살포에 따른 고추 생장촉진 효과는 유기질 비료의 시용수준이 낮은 경우에 더욱 현저하게 나타났다. M. oryzae CBMB20와 메탄올을 혼합 처리한 경우 권장시비수준 100%와 300% 처리 사이에 고추생육과 수량에서 유의성 있는 차이가 없었다. 시비량이 지나치게 많을 경우 생장촉진제의 처리효과를 거둘 수 없으며, 적정한 시비 수준에서 M. oryzae CBMB20와 메탄올을 혼합 처리함으로써 고추를 비롯한 작물의 생장과 수량을 유지하면서도 시비량을 크게 줄일 수 있을 것으로 판단된다.