• Clinical and Experimental Pediatrics
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• 제59권1호
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• pp.8-15
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• 2016

Purpose: Nephrogenesis is normally accompanied by a tightly regulated and efficient vascularization. We investigated the effect of angiotensin II inhibition on angiogenesis in the developing rat kidney. Methods: Newborn rat pups were treated with enalapril (30 mg/kg/day) or vehicle (control) for 7 days after birth. Renal histological changes were checked using Hematoxylin & Eosin staining. We also investigated the intrarenal expression of vascular endothelial growth factor (VEGF)-A, VEGF receptor 1 (VEGFR1), VEGFR2, platelet-derived growth factor (PDGF)-B, and PDGF receptor-${\beta}$ with Western blotting and immunohistochemical staining at postnatal day 8. Expression of the endothelial cell marker CD31 was examined to determine glomerular and peritubular capillary density. Results: Enalapril-treated rat kidneys showed disrupted tubules and vessels when compared with the control rat kidneys. In the enalapril-treated group, intrarenal VEGF-A protein expression was significantly higher, whereas VEGFR1 protein expression was lower than that in the control group (P<0.05). The expression of VEGFR2, PDGF-B, and PDGF receptor-${\beta}$ was not different between the 2 groups. The increased capillary CD31 expression on the western blots of enalapril-treated rat kidneys indicated that the total endothelial cell protein level was increased, while the cortical capillary density, assessed using CD31 immunohistochemical staining, was decreased. Conclusion: Impaired VEGF-VEGFR signaling and altered capillary repair may play a role in the deterioration of the kidney vasculature after blocking of angiotensin II during renal development.

• 보존과학연구
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• 통권19호
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• pp.3-22
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• 1998

The effect of pH on degradation of paper by some fungi, which able to degrade cellulose, was investigated. Trichoderma koningii, Aspergillus nigerand Penicillium nigulosum were cultured at $28^{\circ}C$ for 16 days in the selective medium (PH3, PH4, PH5, PH6, PH7, PH8, PH9, PH10, PHC) containing paper as substrate. Each paper was pretreated with each pH buffer (pH 3∼pH 10, D.W.)prior to addition to the selective medium. Enzyme activities in the each culture medium were measured spectroph to metrically using C.M.C., Avicel, PNPG as the substrates for endoglucanase, exoglucanase and $\beta$-glucosidase, respectively. In all experimental fungi, the enzyme activities of PH3 and PH9 medium were usually much higher than those of other experimental groups. However in the PH6medium, enzyme activity was lower than other groups. To analyze the concentration and pattern of protein in the each culture medium, the medium was concentrated by lyophilization. The protein concentration of PH3 and PH9 medium were relatively high (T.koningii; 6.31mg, 6,19mg, A.niger; 1.62mg, 1.96mg, P.nigulosum;2.50mg, 2.73mg, respectively), but that of PH6 was relatively low. The protein pattern of each medium was analyzed by using SDS-PAGE and VDS Image Master Analysis Program. The concentrations of bands in the each lane were usually high at lane2 (PH3) and lane8 (PH9) and low at lane5 (PH6). Therefore, the incresed cellulolytic activity of fungus against acidified paper could be result of structural change and deterioration of paper caused by being acidified.

• 보존과학회지
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• 제36권1호
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• pp.1-14
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• 2020

This study investigates the crystallinity distribution of ancient silk. Owing to the inherent multi-hierarchical structure of silk protein and the complicated structural changes that occur due to various burial environments, it is challenging but worthwhile to study ancient silk ageing behavior, which is based on the fact that ageing begins with a single fiber and then spreads to a whole fabric. Crystallinity was one of the most effective indicators found to reveal the ageing status of silk. Therefore, a synchrotron radiation-based X-ray diffraction(SR-XRD) method was employed to study the crystallinity distribution of single fibers of ancient silk unearthed from seven archaeological sites in China from historical periods including the warring states, Han dynasty, Song dynasty, and Ming dynasty. In comparison, the conventional X-ray diffraction method, which uses large amounts of samples, was also performed to determine the integral crystallinity of ancient silk. Thermal stability experiments by thermogravimetry(TG) as well as morphology observations by scanning electron microscopy(SEM) and optical microscopy(OM) all confirmed the deterioration of ancient silk. Moreover, the ageing mechanism of ancient silk was proposed with the assistance of an artificial ageing study. The results confirmed the effectiveness of SR-XRD as an ageing indicator, revealing the crystallinity distribution. This research could provide motivation to determine the deterioration status of ancient silk, and would also aid in explaining the fragility of ancient silk due to ageing.

• 한국식품영양학회지
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• 제12권4호
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• pp.409-414
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• 1999

In order to investigate the changes of rice qualities during 4 years storage of paddy stored in ware-house of normal temperature condition. Temperature in warehouse was changed more than 3$0^{\circ}C$ under the influence of average temperature outside of a warehouse. Water content of paddy was not increased over 15% But as average temperature in warehouse was gone up 18$^{\circ}C$ from June to September every years it was supposed that these periods were to be deterioration of rice quality. On investigation of change in paddy it was supposed that these periods were to be deterioration of rice quality. On investigation of change in paddy components during the long term storage, reducing, sugar, amylose, crude protein were increased 0.24%, 19.23%, 7.02% at enterance time to 0.5%, 20.31% 7.46% 4 years later respectively. Max viscosity final visocity and set back value by amylograph were increased 449B,U 610B.U, 161B.U to 493B.U, 715B,U 222B.U but breakdown was decreased 125B.U to 76B.U with the increase of storage period. Gel consistency of rice stored was decreased 44.7mm at enterance time to 39,9mm 4years later. Fatty acid was increased remarkably 4.5KOHmg/100g to 24.4KOHmg/100g. Germination ratio and germ activity of paddy during long-term storage were decreased 97%, 100% to 0%, 0.4% respectively, With the increase of storage period contaminated paddy by molds increased and its by bacteria decreas-ed.

• 한국식품과학회지
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• 제41권3호
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• pp.265-271
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• 2009

본 연구에서는 냉동반죽의 동결장해와 동결손상으로 제빵성이 저하되는 것을 막기 위한 방법의 하나로 단백질-다당류 혼합물(protein-polysaccharide mixtures, 1:1)을 냉동반죽에 첨가하여 빵을 제조하여 품질 특성을 조사하였다. CA 첨가 빵이 총 부피와 비용적에서 가장 높았고 냉동-해동 cycle별 비용적은 첨가 빵이 대조 빵보다 감소율이 작았다. 빵의 저장중 수분함량의 변화는 첨가 빵이 대조 빵보다 감소율이 작아 수분 보유력에 효과가 있음을 알 수 있었다. Crumb 색도는 첨가 빵이 대조 빵보다 $L^{\ast}$값은 높았으나 $a^{\ast}$와 $b^{\ast}$값은 낮았다. Crust 색도는 CA와 CK 첨가 빵은 $L^{\ast}$, $a^{\ast}$, $^{\ast}b$값 모두 대조 빵보다 낮았지만 WK 첨가 빵은 $^{\ast}L$값이 높았다. 저장 기간중 텍스쳐는 대조 빵과 첨가 빵 모두 견고성과 탄력성이 저장중 증가하였다. 응집성은 저장에 따라 WK 첨가 빵이 대조 빵보다 높았고 씹힘성은 $20^{\circ}C$에서 4일간 저장에서만 대조 빵이 CA, CK, WA 첨가 빵보다는 높았다. 관능 평가 결과, 단백질-다당류 혼합물 첨가 빵이 내부 평가와 외부 평가에서 높은 경향을 보였으나 향, 맛, 전체적인 기호도에서는 유의적인 차이를 보이지 않았다. 위의 결과들을 통해 단백질-다당류 혼합물을 첨가할 경우 제빵 적성을 향상시켜주며 CA와 WA를 냉동반죽 제조 시 첨가하면 동결손상으로 인한 제빵성의 저하를 억제할 수 있으며 빵의 노화를 지연시켜 저장수명을 연장시킬 수 있을 것으로 생각된다.

• 한국축산식품학회지
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• 제31권5호
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• pp.710-718
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• 2011

The effects of organic acids mix (0.4%) and modified atmosphere packaging (MAP) on the storage quality of sliced bacon were investigated. Pork bellies were treated with or without organic acids at the curing stage. The organic acids mix comprised 35% sodium acetate, 25% salt, 15% calcium lactate, 11% trisodium citrate, 7% ascorbate, and 7% citric acid. The cured pork bellies were smoked and packaged with 50% $CO_2$ + 50% $N_2$ (50% $CO_2$-MAP) and 100% $N_2$ (100% $N_2$-MAP), and stored at $5^{\circ}C$ for 14 d. The 50% $CO_2$-MAP showed a higher pH value (p<0.05) up to 10 d, a lower protein deterioration (p<0.05) as measured by volatile basic nitrogen (VBN) from 6 to 14 d, and a higher color value of lightness (CIE $L^*$) compared to 100% $N_2$-MAP. The development of lipid oxidation measured by thiobarbituric acid reactive substance (TBARS) values seemed to be effectively controlled throughout the storage period in both 50% $CO_2$-MAP and 100% $N_2$-MAP regardless of the application of organic acids. The 50% $CO_2$-MAP inhibited the growth of aerobic and anaerobic bacteria (p<0.05) both in non-added and bacon added with organic acids mix. The 50% $CO_2$-MAP alone seemed to be effective in delaying the growth of bacteria since the use of organic acids mix gave no additional effects. The addition of organic acids mix lowered the pH value (p<0.05), effectively retarded the protein deterioration (p<0.05), and showed a higher color value of lightness (CIE $L^*$) value (p<0.05) and lower color value of redness (CIE $a^*$) value (p<0.05). In conclusion, 50% $CO^2$-MAP showed better quality and self-life of sliced bacon during storage. However, the beneficial effect of organic acids mix was not noticed in the concentration used in this experiment.

• 한국축산식품학회지
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• 제33권6호
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• pp.737-743
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• 2013

The aim of this research is to evaluate the effects of cooking time and storage temperature on the quality of home-made retort pouch packed Chuncheon Dakgalbi. The leg meat of broiler is being cut into cubes and is mixed with the Dakgalbi sauce and vegetables. Around 200 g of Chuncheon Dakgalbi is being stuffed into a retort pouch and then vacuumed. The retort pouch packed Chuncheon Dakgalbi is subjected to cooking (autoclaving) at $110^{\circ}C$ and 0.75 Kgf for 10, 20 or 30 min and then transferred to the chilling room at $2^{\circ}C$ for rapid cooling procedures. Subsequently, the samples are stored at $4^{\circ}C$ or $25^{\circ}C$ for 4 wk. According to results of sensory evaluation, the highest sensory scores were found in Chuncheon Dakgalbi which was cooked for 30 min (p<0.05). Prolonged cooking time tends to decrease the pH, CIE $L^*$ and CIE $a^*$ levels, and slightly promote the lipid oxidation and protein deterioration. The Chuncheon Dakgalbi being cooked for 10 min promoted the lipid oxidation and protein deterioration during storage at $25^{\circ}C$. Moreover, the total aerobic and anaerobic bacteria in Chuncheon Dakgalbi being cooked for 10 min started to grow after 3 wk of storage at $25^{\circ}C$. Cooking (autoclaving) at $110^{\circ}C$ for 30 min is able to maintain the quality and shelf-life of retort pouch packed Chuncheon Dakgalbion the market.

• 한국식품조리과학회지
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• 제31권5호
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• pp.565-573
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• 2015

항산화 활성을 갖는 렌틸(0%, 5%, 10%)과 백년초(0%, 3%)의 첨가로 인해 나타나는 소시지의 저장 기간 중 안정성을 알아보기 위해 발색과 Clostridium Botulinum 증식 억제 등을 위해 첨가하는 아질산염을 첨가하지 않았으며 총 폴리페놀, DPPH 라디칼 소거능, pH, 산가, 과산화물가, VBN, 총균수를 측정하였다. 1. 렌틸과 백년초는 첨가량 증가에 따라 소시지의 총 폴리페놀과 DPPH 라디칼 소거능은 유의적으로 높아졌다. 백년초 보다 렌틸에 의한 효과가 더 크게 나타났으며 혼합첨가에 의해 효과가 상승하였다. 저장기간이 경과함에 따라 총 폴리페놀과 DPPH 라디칼 소거능은 유의적으로 감소하였다. 2. 렌틸과 백년초 첨가에 의한 지방산패 억제효과는 렌틸과 백년초 첨가량 증가에 따라 유의적으로 높아졌다. 저장기간이 경과함에 따라 산가와 과산화물가는 증가하였으나 대조군에 비해 첨가군의 지방산패 억제효과는 크게 나타났다. 3. 단백질 변패여부를 알 수 있는 VBN은 저장기간이 경과함에 따라 VBN 함량이 증가하였으나 대조군에 비해 첨가군의 증식이 억제되었다. 렌틸과 백년초는 지방산패 억제효과와 마찬가지로 단백질 변패 억제효과도 나타났다. 4. 렌틸과 백년초 첨가에 따른 일반세균에 대한 유의차가 없었다. 저장기간이 경과함에 따라 일반세균은 유의적으로 증가하였으나 백년초 첨가군의 세균증식이 적게 나타나 백년초 에탄올 추출물이 항균효과가 있음을 알 수 있었다. 따라서 렌틸과 백년초의 첨가는 소시지의 지방산패 및 단백질 변패 억제, 미생물 증식 억제 등의 효과를 나타내어 30일 저장 기간 중 안정성을 확보할 수 있었으며 첨가량이 많을수록 효과는 크게 나타났다.

• 한국초지조사료학회지
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• 제14권2호
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• pp.132-141
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• 1994

본 시험은 reed canarygrass silage의 품질을 향상시키고 호기적 변패를 방지시킬 목적으로 재료를 약 1.5cm 길이로 절단하여 formic acid, caproic acid 및 두가지 산을 혼합하여 첨가한 silage를 9개의 처리구로 나누어 실험용 silo에 제조하였으며, silage의 품질분석을 위해서 두께 0.1mm, 용량 50kg의 vinyl bag을 이용하였다. 또한 호기적 상태에서의 온도변화, 질소 함량 변화 및 변패방지를 위한 silage의 안정성 시험은 지름 25cm$\times$높이 30cm의 plastic용기를 이용하여 개봉 직후와 7일간의 호기적 조건에서 실시한 결과를 요약하면 다음과 같다. 2. Silage의 화학적 조성에서 개봉 직후의 조단백질과 NFE함량은 formic acid와 caproic acid를 혼합 첨가함으로서 높았으며(P<0.01), 7일간의 호기적 상태에서는 혼합 첨가를 함으로서 조섬유와 ADF함량이 낮게 나타났다.(PM0.01). 2. Silage의 온도변화는 formic acid를 첨가함으로서 개봉 2일에 최고온도($34.4^{\circ}C$)에 도달했으며, caproic acid의 첨가와 formic acid + caproic acid의 혼합첨가를 함으로서 온도상승을 방지할 수 있었다. 3. 호기적 상태에서 silage의 pH변화는 formic acid를 첨가할 경우에는 효과가 없었으나, caproic acid를 첨가함으로서 silage의 pH는 안정되었다. 4. 총 질소에 대한 암모니아태 질소의 함량비율은 formic acid첨가구>caproic acid 첨가구>혼합첨가구 순으로 유의적으로 나타났다(P<0.01) 5. Caproic acid 1.2%첨가와 formic acid의 혼합 첨가(1.2%+1.2%)를 함으로서 mould의 성장을 억제하는 효과가 크게 나타났다.

• 한국축산식품학회지
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• 제35권4호
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• pp.557-563
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• 2015

The present study was carried out to investigate the effects of soy protein hydrolysates (SPHs) addition on the quality characteristics of pork patties. The SPHs was prepared by subcritical water process (SWP) at 180℃ without holding time and mixed with the pork patty components at varying concentrations (0-3%), and the patties were stored at 4℃ for 14 d. As quality parameters, instrumental color, thiobarbituric acid-reactive substances (TBARS), pH, water holding capacity (WHC) and shear force were measured at the end of storage. Regardless of SPHs concentration, the addition of SPHs significantly manifested low L* and high a* values compared to those of untreated control (p<0.05). For b* value, addition of SPHs in the 0.5-1.5% was unaffected, while >2.0% of SPHs caused significantly lower b* than control (p<0.05). The color changes in pork patties with and without SPHs were also identified in visual appearance where the pork patties containing 0.5-2.0% showed bright red color which was comparable to brownish color of control and patties containing >2.5% SPHs. Lipid oxidation was delayed by the addition of 0.5-1.5% SPHs, while it was accelerated by the addition of 3% SPHs. The pH of patties increased with increasing concentration of SPHs, whereas there were no significant differences in WHC and shear force of patties. Consequently, the results indicated that the addition of 0.5-1.5% SPHs had a potential advantage in suppressing oxidative deterioration of fat-containing meat products during chilled storage.