Isolation of endo-1,4-b-D-glucanase producing Bacillus subtilis sp. from fermented foods and enhanced enzyme production bydeveloping the mutant strain

Seo, Jakyeom,Park, Eunhye,Leek, Sung Sill,Kim, Byeongwoo,Shin, Teaksoon,Cho, Byungwook,Cho, Seongkeun,Cho, K. J.,Ha, Jong K. Agricultural Research Communication Center 2017 Indian journal of animal research Vol.51 No.-

<P>Cellulolytic bacteria living in food can be applied to microbial feed additives to improve fiber digestion in animal feeds. In this study, a cellulase-producing bacteria was isolated from salted clam and treated with physical or chemical agents to enhance their enzyme production. The bacteria was identified as a strain of Bacillus subtilis on the basis of 16S rRNA analysis. Endo-1,4-beta-D-glucanase (endoglucanase) was produced by the wild type using 0.4% carboxy-methyl-cellulose as a carbon source with maximal activity (0.04 U/mL) after 24 h incubation. Insoluble cellulose and oat spelt xylan were also used as carbon sources for investigation of exoglucanase and xylanase,however, these enzymes were not found in the culture supernatant. Maximum endoglucanase activity of Bacillus subtilis sp. was measured at 50 degrees C and pH 5, respectively. Then, the strain was subjected to classical mutagenesis (UV-irradiation and chemical treatment) to improve endoglucanase production. A mutant strain, Pll treated with ethyl methyl sulfonate was finally selected. Mutant Pll was sub-cultured and tested for endoglucanase production, which was 0.05 U/mL after 24 h growth. The significant difference of endoglucanase production between wild type and mutant Pll was prolonged to 10th generation. Thus, the mutant strain was found to have enhanced endoglucanase production.</P>

RESEARCH : Open Access ; Meta-analysis of factors affecting milk component yields in dairy cattle

( Jun Sung Lee ),( Jakyeom Seo ),( Se Young Lee ),( Kwang Seok Ki ),( Seong Won Seo ) 한국동물자원과학회(구 한국축산학회) 2014 한국축산학회지 Vol.56 No.5

The objectives of this study were thus to identify most significant factors that determine milk component yield (MCY) using a meta-analysis and, if possible, to develop equations to predict MCY using variables that can be easily measured in the field. A literature database was constructed based on the research articles published in the Journal of Dairy Science from Oct., 2007 till May, 2010. The database consisted of a total of 442 observed means for MCY from 118 studies. The candidate factors that determine MCY were those which can be routinely measured in the field (e.g. DMI, BW, dietary forage content, chemical composition of diets). Using a simple linear regression, the best equations for predicting milk fat yield(MFY) and milk protein yield (MPY) were MFY = 0.351 (±0.068) + 0.038 ( 0.003) DMI (R2 = 0.27), and MPY = 0.552 (±0.071) + 0.031 (±0.002) DMI - 0.004 (±0.001) FpDM (%, forage as a percentage of dietary DM) (R2 = 0.38), respectively. The best equation for predicting milk fat content (%) explained only 12% of variations in milk fat content, and none of a single variable can explain more than 5% of variations in milk protein content. We concluded that among the tested variables, DMI was the only significant factor that affects MFY and both DMI and FpDM significantly affect MPY. However, predictability of linear equations was relatively low. Further studies are needed to identify other variables that can predict milk component yield more accurately.

Meta-analysis of factors affecting milk component yields in dairy cattle

Lee, Junsung,Seo, Jakyeom,Lee, Se Young,Ki, Kwang Seok,Seo, Seongwon Korean Society of Animal Sciences and Technology 2014 한국축산학회지 Vol.56 No.2

The objectives of this study were thus to identify most significant factors that determine milk component yield (MCY) using a meta-analysis and, if possible, to develop equations to predict MCY using variables that can be easily measured in the field. A literature database was constructed based on the research articles published in the Journal of Dairy Science from Oct., 2007 till May, 2010. The database consisted of a total of 442 observed means for MCY from 118 studies. The candidate factors that determine MCY were those which can be routinely measured in the field (e.g. DMI, BW, dietary forage content, chemical composition of diets). Using a simple linear regression, the best equations for predicting milk fat yield(MFY) and milk protein yield (MPY) were $MFY=0.351({\pm}0.068)+0.038({\pm}0.003)$ DMI ($R^2=0.27$), and $MPY=0.552({\pm}0.071)+0.031({\pm}0.002)DMI-0.004({\pm}0.001)$ FpDM (%, forage as a percentage of dietary DM) ($R^2=0.38$), respectively. The best equation for predicting milk fat content (%) explained only 12% of variations in milk fat content, and none of a single variable can explain more than 5% of variations in milk protein content. We concluded that among the tested variables, DMI was the only significant factor that affects MFY and both DMI and FpDM significantly affect MPY. However, predictability of linear equations was relatively low. Further studies are needed to identify other variables that can predict milk component yield more accurately.

High-level dietary crude protein decreased backfat thickness and increased carcass yield score in finishing Hanwoo beef cattle (Bos taurus coreanae)

( Seoyoung Jeon ),( Mingyung Lee ),( Jakyeom Seo ),( Jeong-hoon Kim ),( Dong-Keun Kam ),( Seongwon Seo ) 한국축산학회 2021 한국축산학회지 Vol.63 No.5

Recently, a high level of dietary crude protein (CP) has become of interest as a possible practice to improve the carcass quality of beef cattle, and its level has been increasing in the field. However, there is little scientific evidence that supports this. This study was conducted to test whether a high dietary CP level would improve growth performance, body metabolism, and carcass traits in Hanwoo beef cattle. A total of 32 Hanwoo finishing beef cattle (18 multiparous cows, six heifers, and eight steers) participated in a 12-weeks feeding trial. Two kinds of total mixed rations were prepared to contain two different CP; 156 g/kg for the control (CON) and 173 g/kg of CP for the treatment (HCP), while maintaining a similar level of metabolizable energy. The experiment was ended when more than half of the steers reached the target body weight (730 kg). Blood was collected at the end of the experiment. After harvesting, the carcass trait was evaluated at the slaughterhouse according to Korean standards. The carcass yield score and grade were also calculated based on revised criteria. Overall, dry matter intake, average daily gain, blood metabolites concentration, and the carcass traits, except for backfat thickness and the yield score, did not differ between the treatments. The HCP had lower backfat thickness than those of CON. There was no difference in the carcass yield grade, but the yield score was higher in the HCP treatment. According to the newly revised carcass grading criteria, both yield score and grade were higher in HCP than in CON. Increasing CP supply decreased the carcass’s backfat thickness without altering growth performance and body metabolism, resulting in improved yield score and grade. Therefore, feeding a high CP diet may be beneficial in the farm income, although it may also increase feed cost and nitrogen excretion to the environment.

Short Communication: Negative association between high temperature-humidity index and milk performance and quality in Korean dairy system: big data analysis

Dongseok Lee,Daekyum Yoo,Hye Ran Kim,Jakyeom Seo 한국축산학회 2023 한국축산학회지 Vol.65 No.3

The aim of this study was to investigate the effects of heat stress on milk traits in South Korea using comprehensive data (dairy production and climate). The dataset for this study comprised 1,498,232 test-day records for milk yield, fat- and protein-corrected milk, fat yield, protein yield, milk urea nitrogen (MUN), and somatic cell score (SCS) from 215,276 Holstein cows (primiparous: n = 122,087; multiparous: n = 93,189) in 2,419 South Korean dairy herds. Data were collected from July 2017 to April 2020 through the Dairy Cattle Improvement Program, and merged with meteorological data from 600 automatic weather stations through the Korea Meteorological Administration. The segmented regression model was used to estimate the effects of the temperature-humidity index (THI) on milk traits and elucidate the break point (BP) of the THI. To acquire the least-squares mean of milk traits, the generalized linear model was applied using fixed effects (region, calving year, calving month, parity, days in milk, and THI). For all parameters, the BP of THI was observed; in particular, milk production parameters dramatically decreased after a specific BP of THI (p < 0.05). In contrast, MUN and SCS drastically increased when THI exceeded BP in all cows (p < 0.05) and primiparous cows (p < 0.05), respectively. Dairy cows in South Korea exhibited negative effects on milk traits (decrease in milk performance, increase in MUN, and SCS) when the THI exceeded 70; therefore, detailed feeding management is required to prevent heat stress in dairy cows.

Development of a novel endolysin, PanLys.1, for the specific inhibition of Peptostreptococcus anaerobius

Joonbeom Moon,Hanbeen Kim,Dongseok Lee,Jakyeom Seo Asian Australasian Association of Animal Productio 2023 Animal Bioscience Vol.36 No.8

Objective: The objective of this study was to develop a novel endolysin (PanLys.1) for the specific killing of the ruminal hyper-ammonia-producing bacterium Peptostreptococcus anaerobius (P. anaerobius). Methods: Whole genome sequences of P. anaerobius strains and related bacteriophages were collected from the National Center for Biotechnology Information database, and the candidate gene for PanLys.1 was isolated based on amino acid sequences and conserved domain database (CDD) analysis. The gene was overexpressed using a pET system in Escherichia coli BL21 (DE3). The lytic activity of PanLys.1 was evaluated under various conditions (dosage, pH, temperature, NaCl, and metal ions) to determine the optimal lytic activity conditions. Finally, the killing activity of PanLys.1 against P. anaerobius was confirmed using an in vitro rumen fermentation system. Results: CDD analysis showed that PanLys.1 has a modular design with a catalytic domain, amidase-2, at the N-terminal, and a cell wall binding domain, from the CW-7 superfamily, at the C-terminal. The lytic activity of PanLys.1 against P. anaerobius was the highest at pH 8.0 (p<0.05) and was maintained at 37℃ to 45℃, and 0 to 250 mM NaCl. The activity of PanLys.1 significantly decreased (p<0.05) after Mn²⁺ or Zn²⁺ treatment. The relative abundance of P. anaerobius did not decrease after administration PanLys.1 under in vitro rumen conditions. Conclusion: The application of PanLys.1 to modulate P. anaerobius in the rumen might not be feasible because its lytic activity was not observed in in vitro rumen system.

반추위 삽입 센서를 활용한 육성기 홀스타인 거세우의 생리 상태 변화 평가

왕준호 ( Junho Wang ),유대겸 ( Daekyum Yoo ),서자겸 ( Jakyeom Seo ) 한국축산학회 2022 축산기술과 산업 Vol.9 No.1

In the last decade, the wireless biosensor technologies for cattle have been widely spread over the world. The objective of this study was to evaluate the changes of physiological state in Holstein growing steers using the rumen bolus sensor. A total of thirty-two Holstein young steers (219.48 ± 16.61 kg, 7.25 ± 0.40 months of age) were used and the rumen bolus was orally administered to each steer before conducting this experiment. The rumen bolus used in this study (Smart alyacⓇ, Hankook Iot Corp, Gimcheon, Korea) can measure not only body temperature (BT) but also moving behavior which was expressed as indices (moving index, MI). All steers equipped with the bolus sensor were housed in pens (4 animals per pen) and the sensor data were collected for 29 days. During experimental period, the average MI for the day (day: 0700-1900, night: 2000-0600) was significantly higher than that for the night (day: 111.10, night: 98.53, p < 0.0001), but the result of average BT was opposite (day: 39.04℃, night: 39.62℃, p < 0.0001). The average MI in animals having low average daily gain (ADG) was higher than those having high ADG (low ADG: 105.46, high ADG: 103.66, p < 0.0001) and average BT was the same (low ADG: 39.41℃, high ADG: 39.33℃, p < 0.0001). When the steers exposed to several stresses, the average MI was significantly lower than that in normal condition (normal: 117.40, stress: 109.88, p < 0.01). Stressed steers also showed increased BT compared to steers in normal condition (normal: 38.78℃, stress: 39.50℃, p < 0.0001). In conclusion, rumen bolus sensors, which generally used in cows to detect estrus, can be applied even to steers to detect the physiological changes rapidly in stressful environment.

Contribution analysis of Hanwoo carcass traits on unit price in national slaughter house

Seung-Hoon Eum,Hu-Rak Park,Jakyeom Seo,Seong-Keun Cho,Byeong-Woo Kim 충남대학교 농업과학연구소 2016 Korean Journal of Agricultural Science Vol.43 No.4

Analysis of environmental effects affecting reproductive traits of primiparous and multiparous Hanwoo

Seung-Hoon Eum,Hu-Rak Park,Jakyeom Seo,Seong-Keun Cho,Byeong-Woo Kim 충남대학교 농업과학연구소 2016 Korean Journal of Agricultural Science Vol.43 No.3

Contribution analysis of carcass traits on auction price for Hanwoo in Gyeonggi province

Jewoong Yun,Yoseph Kim,Jieun Lee,Tae Hun Kang,Myunghoo Kim,Jakyeom Seo,Seong-Keun Cho,Byeong-Woo Kim 충남대학교 농업과학연구소 2021 Korean Journal of Agricultural Science Vol.48 No.3