• The Journal of Advanced Prosthodontics
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• 제13권1호
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• pp.24-35
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• 2021

PURPOSE. This study was to evaluate the effect of rinsing time on the accuracy of interim crowns fabricated by digital light processing. MATERIALS AND METHODS. The maxillary right first molar master die was duplicated using a silicone material, while a study die was produced using epoxy resin. Scans of the epoxy resin die were used in combination with CAD software to design a maxillary right first molar interim crown. Based on this design, 24 interim crowns were fabricated with digital light processing. This study examined the trueness and precision of products that were processed with one of the three different postprocessing rinsing times (1 min, 5 min, and 10 min). Trueness was measured by superimposing reference data with scanned data from external, intaglio, and marginal surfaces. Precision was measured by superimposing the scan data within the group. The trueness and precision data were analyzed using Kruskal-Wallis, nonparametric, and post-hoc tests, and were compared using a Mann-Whitney U test with Bonferroni correction (α=.05). RESULTS. The trueness of the external and intaglio surfaces of crowns varied significantly among the different rinsing times (P=.004, P=.003), but there was no statistically significant difference in terms of trueness measurements of the marginal surfaces (P=.605). In terms of precision, statistically significant differences were found among the external, intaglio, and marginal surfaces (P=.001). CONCLUSION. Interim crowns rinsed for 10 minutes showed high accuracy.

• 한국환경농학회지
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• 제39권4호
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• pp.352-359
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• 2020

BACKGROUND: The mulberry cultivars 'Daeshim' and 'Shimgang' were developed in RDA in 2014 and 2017, respectively. 'Daeshim' yields a fruit size bigger than that of other varieties and has a productivity of over 70%, whereas 'Shimgang' has a high yield and a special characterization against the mulberry popcorn disease. In our study, a compositional comparison of these popular cultivars in Korea was undertaken to explore the nutrient profiles of mulberry fruit and promote the development of the rich minerals and flavonoids in mulberry fruit as performing each other irrigation time. METHODS AND RESULTS: These two cultivars were collected from the Sericulture and Apiculture Division, RDA, in Korea to investigate their amounts, weights, minerals, and flavonoid content using each other instrument. After 6 h of irrigation treatment, the amount of fruit (kg/tree) from Daeshim and Shimgang increased by 17.5 and 15.2 kg/tree, respectively. The total flavonoid content from Daeshim and Shimgang was determined to be 132.9 mg and 36.3 mg, respectively, after the 6 h irrigation treatment. CONCLUSION: Appropriate irrigation treatment methods such as water scheduling and volume will help increase fruit quantities and farmer incomes. It would be interesting to conduct further in-depth research on these fruits so that consumers can benefit from them as a food additive.

• 접착 및 계면
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• 제21권4호
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• pp.135-142
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• 2020

최근 미세플라스틱과 같은 환경 문제로 석유계 플라스틱을 대체할 자연 유래 친환경 플라스틱에 대한 사람들의 관심이 증가하고 있다. 점·접착제 분야에서도 이런 추세에 맞추어 천연 유래 소재를 이용한 친환경 점·접착제들이 개발되고 있다. 그 중에서 엿당은 전분에서 유래한 천연 물질이며 식품 첨가제로 쓰이는 물엿의 주성분이다. 전분보다 낮은 분자량 때문에 물에 쉽게 녹고 무엇보다 이를 이용해 용액중합으로 다른 단량체와 공중합 될 수 있다는 가능성이 있다. 그러나 아직 엿당을 이용하여 점·접착제에 응용한 연구는 미비한 실정이다. 본 연구에서는 엿당을 아크릴 무수물로 개질한 후 FT-IR과 H-NMR을 통해 개질여부를 확인하였다. 그리고 개질한 엿당을 2종의 아크릴 단량체와 공중합 하였다. 합성한 수지의 접착 성능은 목재접착을 통해 조사하였다.

• Journal of Animal Science and Technology
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• 제63권1호
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• pp.16-24
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• 2021

The suppressive effect of monensin as an ionophore-feed additive on enteric methane (CH4) emission and renewable methanogenesis were evaluated. To clarify the suppressive effect of monensin a respiratory trial with head cage was performed using Holstein-Friesian steers. Steers were offered high concentrate diets (80% concentrate and 20% hay) ad libitum with or without monensin, galacto-oligosaccharides (GOS) or L-cysteine. Steers that received monensin containing diet had significantly (p < 0.01) lower enteric CH4 emissions as well as those that received GOS containing diet (p < 0.05) compared to steers fed control diets. Thermophilic digesters at 55℃ that received manure from steers fed on monensin diets had a delay in the initial CH4 production. Monensin is a strong inhibitor of enteric methanogenesis, but has a negative impact on biogas energy production at short retention times. Effects of the activity of coprophagous insects on CH4 and nitrous oxide (N2O) emissions from cattle dung pats were assessed in anaerobic in vitro continuous gas quantification system modified to aerobic quantification device. The CH4 emission from dungs with adults of Caccobius jessoensis Harold (dung beetle) and the larvae of the fly Neomyia cornicina (Fabricius) were compared with that from control dung without insect. The cumulative CH4 emission rate from dung with dung insects decreased at 42.2% in dung beetles and 77.8% in fly larvae compared to that from control dung without insects. However, the cumulative N2O emission rate increased 23.4% in dung beetles even though it reduced 88.6% in fly larvae compared to dung without coprophagous insects. It was suggested that the antibacterial efficacy of ionophores supplemented as a growth promoter still continued even in the digested slurry, consequently, possible environmental contamination with the antibiotics might be active to put the negative impact to land ecosystem involved in greenhouse gas mitigation when the digested slurry was applied to the fields as liquid manure.

• 치위생과학회지
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• 제21권1호
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• pp.38-44
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• 2021

Background: Dental caries and periodontal disease are bacterial infectious disease, mainly caused by plaque, a bacterial colony deposited on the tooth surface and gum tissue. Dental plaque disclosants easily stain the dental plaque, making them effective for scaling and tooth brushing education. As the erythrosine typically contained in dental plaque disclosants is highly cytotoxic, a low toxicity additive is needed. In this study, we aimed to examine the natural pigments with negligible cytotoxicity but can effectively stain the dental plaques for use in dental plaque disclosants. Methods: The pigmentation of eight types of natural pigments was tested on bovine tongue and teeth, as well as on head and neck tissue sections of experimental ICR mice. The cytotoxicity of gingival epithelial cells was measured via MTT assay. Pigmentation was performed on the bovine tongue and tooth surface. Pigmentation in the oral environment was observed in four mandibular incisors. A 2 Tone was used as a control. Results: Of the eight types of natural pigments, purple and blue pigments were effective in coloring dental plaques on the enamel surface as well as in the head and neck tissue sections. Additionally, purple and blue pigments were visible on the surface of the bovine tongue. Red, pink, orange, green, purple, and yellow pigments showed strong cytotoxicity, whereas brown and blue pigments had relatively low cytotoxicity. Blue pigment was effective in staining the dental plaque of four mandibular incisors. Conclusion: We suggest that the blue pigment derived from Gardenia jasminoides Ellis (Rubiaceae), which is effective for coloring dental plaques and has low cytotoxicity, is useful as a naturally derived dental disclosant.

• 농업과학연구
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• 제49권3호
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• pp.547-560
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• 2022

The present study investigated the effects of dietary supplementation of peanut shell extract on the growth performance and physiological properties of broiler chicks. Two diet energy levels (Positive and Negative) and four additives (0.0, 0.05, and 0.1% peanut shell extract and commercial antioxidant) were factorially arranged for eight treatments. The overall weight gain of the broilers was slightly improved at 0.05% for the antioxidant treatments regardless of the diet energy levels, but there was no statistical difference among the treatments (p > 0.05). The carcass characteristics of the broilers, such as cooking loss, crude protein content, antioxidant activity, and thiobarbituric acid reactive substances (TBARS) values, were improved by the feeding diets containing the 0.05% peanut shell extract. Furthermore, it was confirmed that the dietary supplementation of peanut shell extract did not have a negative effect on the immune responses of the broilers show by the lack of statistical differences in the liver and bursa Fabricious weight and cytokine level among the treatments. From the economic analysis, dietary supplementation of peanut shell extract significantly influenced the compensatory growth and food efficiency and, in turn, led to a decrease in the duration needed to reach 1.5 kg compared to the control. These results suggest the possibility that the peanut shell extract could be used as a functional feed additive by improving the growth performance and carcass characteristics with no detrimental effects on broilers.

• Journal of Microbiology and Biotechnology
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• 제34권2호
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• pp.436-456
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• 2024

Several thermostable proteases have been identified, yet only a handful have undergone the processes of cloning, comprehensive characterization, and full exploitation in various industrial applications. Our primary aim in this study was to clone a thermostable alkaline protease from a thermophilic bacterium and assess its potential for use in various industries. The research involved the amplification of the SpSKF4 protease gene, a thermostable alkaline serine protease obtained from the Geobacillus thermoglucosidasius SKF4 bacterium through polymerase chain reaction (PCR). The purified recombinant SpSKF4 protease was characterized, followed by evaluation of its possible industrial applications. The analysis of the gene sequence revealed an open reading frame (ORF) consisting of 1,206 bp, coding for a protein containing 401 amino acids. The cloned gene was expressed in Escherichia coli. The molecular weight of the enzyme was measured at 28 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The partially purified enzyme has its highest activity at a pH of 10 and a temperature of 80℃. In addition, the enzyme showed a half-life of 15 h at 80℃, and there was a 60% increase in its activity at 10 mM Ca²⁺ concentration. The activity of the protease was completely inhibited (100%) by phenylmethylsulfonyl fluoride (PMSF); however, the addition of sodium dodecyl sulfate (SDS) resulted in a 20% increase in activity. The enzyme was also stable in various organic solvents and in certain commercial detergents. Furthermore, the enzyme exhibited strong potential for industrial use, particularly as a detergent additive and for facilitating the recovery of silver from X-ray film.

• 한국식품영양과학회지
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• 제41권10호
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• pp.1402-1408
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• 2012

본 연구는 부산물로 버려지는 오디박의 식품 소재로서의 활용가능성을 위한 기초연구로 이화학적 품질 특성 및 항산화성을 분석하여 오디 및 오디 농축액과 비교하였다. 오디와 오디박은 동결건조 하여 사용하였고, 오디즙은 농축하여 사용하였으며, 수분함량은 건오디는 7.32%, 오디박은 6.0%이었고 농축액의 가용성 고형물 함량은 $24.7^{\circ}Brix$이었다. 환원당 함량은 건오디가 45.7%로 가장 높았으며, 오디박은 24.5%, 농축액은 30.9%이었다. pH는 건오디, 5.81, 오디박, 5.92, 오디농축액은 5.80이었으며, 산도는 건오디가 0.064%, 오디박이 0.035%, 오디 농축액이 0.080%이었다. 일반성분으로 탄수화물과 조회분은 건오디가 높았으며, 조단백, 조지방 및 조섬유는 건오디박이 높게 나타났다. 색도는 적색도를 나타내는 a값은 건오디가 4.7, 건오디박이 4.3으로 오디박은 오디와 유사하였다. 총 phenol 함량은 건오디가 0.039 mg/mL로 가장 높았고, 오디박은 0.026 mg/mL, 오디 농축액은 0.024 mg/mL였다. 총 flavonoid 함량은 건오디박이 0.48 mg/mL로 가장 높았고 건조오디는 0.26 mg/mL, 오디 농축액은 0.14 mg/mL였다. DPPH radical 소거능의 $IC_{50}$ 값(건오디: 5.89 mg/mL, 오디박: 7.86 mg/mL, 오디 농축액: 33.47 mg/mL) 및 hydroxyl radical 소거능의 $IC_{50}$ 값(오디: 20.50 mg/mL, 오디박: 22.59 mg/mL, 농축액: 52.94 mg/mL)은 농축액에 비하여 건조오디와 오디박이 높았다. ABTS radical 소거능은 건오디(6.92%)>오디박(4.53%)>농축액(3.27%)의 순이었고, FRAP은 건오디(0.036 mg/mL)>오디박(0.021 mg/mL)>농축액(0.011 mg/mL)의 순이었다. 이상의 결과로부터 오디농축액 제조 시 부산물로 얻어져 폐기되는 오디박은 색상이 우수하고, 당함량은 적고 식이섬유와 조단백이 풍부할 뿐 아니라, 총플라보노이드 및 페놀함량이 높아 항산화능이 우수하므로 가공식품 또는 건강기능 식품소재로 활용가치가 매우 높다고 사료된다.

• 한국식품과학회지
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• 제34권6호
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• pp.1048-1056
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• 2002

생강다대기의 저장중 가스 발생량의 변화를 살펴보면 무처리구는 가스가 급격하게 증가 하였지만 단독처리구와 종합처리구는 가스발생량이 경미하였다. 고액분리의 정도는 xanthan gum을 첨가한 단독처리구와 종합처리구가 고액분리에 대한 안정성을 나타내었으며 ${\Delta}E$값은 종합처리구가 저장 120일이 경과하여도 1.87에서 2.99사이로 저장 초기와 큰 차이를 보이지 않아 가장 안정적이었다. 다대기 제품의 저장중 pH 변화는 종합처리구만이 안정적인 경향을 나타내었고, 모든 처리구들의 총 유기산 함량 변화는 저장기간이 길어질수록 증가하는 경향을 보였으며, 이것은 유기산 중 lactic acid의 현저한 증가에 의한 것으로 나타났으며 무처리구와 비교하여 종합처리구는 증가율이 억제되어 저장 60일까지 가장 안정적이었다. 저장기간 동안의 유리 아미노산 함량 변화는 저장기간이 길어질수록 감소하는 경향을 나타내었지만 종합처리구는 일정한 수준을 유지하였고, 처리구별 총 유리당 함량의 감소율은 무처리구 > 종합처리구 > L-cysteine 처리구 > sodium bisulfite 처리구 순으로 증가하였다. 다대기 제품의 저장기간에 따른 관능적 특성으로 색깔, 이취, 전체적인 선호도는 종합처리구가 가장 우수한 제품으로 평가되었고, 저장 중 무처리구와 종합처리구간의 지방산 조성차이는 나타나지 않았다. 이상의 결과를 종합해 볼 때 생강 다대기를 $5^{\circ}C$에서 장기 저장하면서 발생하는 갈변, 가스발생, 고액분리 등을 효과적으로 억제하기 위해서는 갈변억제제인 L-cysteine 0.2%, 가스발생억제제인 sodium benzoate 0.1%와 NaCl 2% 그리고 고액분리억제제인 xanthan gum 0.1%를 단독으로 처리하는 것보다 이들 첨가물들을 혼합하여 종합적으로 처리하는 것이 우수한 품질의 생강 다대기를 제조, 유통하는데 필요하였다.

• 육가공
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• 통권34호겨울호
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• pp.14-25
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• 2007

본 연구는 3종의 식품 첨가제 미함유 그릴 돈육 햄 제품(T1; 등심, T2; 안심, T3; 뒷다리)에 대한 물리화학적, 미생물학적 및 관능적 품질특성의 변화를 조사하고자 실시하였다. 제품 제조 시 열처리는 그릴러에서 $60^\circC$ 30분간 저온가열, $150^\circC$ 50분간 고온가열 총 80분간 실시하였으며, 방냉 후 PA/PE 필름에 넣고 진공 포장하여 $4\pm$$1^\circC$에서 40일 저장하였다. pH 범위는 저장 초기 5.92(T1)~6.10(T3) 에서 저장 말기 6.28(T1)~6.60(T3)의 범위였다. 보수력은 T1은 85.99~93.24 %, T2 는 85.26~93.89%, T3는 89.11~94.67% 범위를 보였으며, T3가 다소 높은 경향이었다. 전단가는 T3 제품들이 전 저장기간 동안 높은 값을 나타내었다(p<0.05). TBARS와 VBN은 T2가 다른 처리구들보다 유의적으로 높았다(p< 0.05). 저장 40일까지 총 균수와 유산균수는 각각 1.93~3.48, 1.74~3.48 log10 CFU/g 수준으로 매우 양호한 편으로 $4\pm$$1^{\circ}C$에 보관 시 저장 40일까지 안전성을 확보하고 있었으며, 또한 저장 40일까지 전체적인 기호성이 5.0 이상을 유지하여 상품화 가능성이 입증되었다.