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Production of Fructooligosaccharides by an Amyloglucosidase (Amyloglucosidase에 의한 Fructooligosaccharides의 생산)

  • 윤종원;이민규송승구
    • KSBB Journal
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    • v.9 no.2
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    • pp.127-132
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    • 1994
  • A new method of fructooligosaccharides production was investigated by an amyloglucosidase using sucrose as a substrate. Optimum reaction conditions were as follows: sucrose concentration, 700g/$\ell$; pH 5.5; temperature, $55^{\circ}C$; enzyme dosage, 48 units per gram sucrose. At the optimized reaction conditions, 41.5% of fructooligosaccharides were produced after 25 hours. A hydrolyzing activity was stronger than transfructosylting activity at low sucrose concentrations, resulting in low production rate of fructooligosaccharides. The optimum pH and temperature in both transfructosylating(pH 5.5, $60^{\circ}C$) and hydrolyzing activity(pH$4.75^{\circ}C$)were significantly different from each other. The amyloglucosidase also utilized fructooligosaccharides as a substrate and glucose seemed to be an inhibitor.

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Microscopic Anatomy of Male Reproductive Organ in the Long Arm Octopus Octopus minor (Cephalopoda: Octopodidae) (낙지 Octopus minor 수컷 생식기관의 미세해부학적 구조)

  • Seong Jin Kim;Hyeon Jin Kim;So Ryung Shin;Myeong Gyo Seo;Pyeong Woo Kim;Eun Ha Kim;Jung Sick Lee
    • Journal of Marine Life Science
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    • v.8 no.2
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    • pp.178-185
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    • 2023
  • This study was described the microscopic anatomy of male reproductive organs and spermatophore necessary for understanding the reproductive ecology of the long arm octopus Octopus minor. The long arm octopus was a species that has sexual dimorphism that can distinguish between sex based on the presence of hectocotylus. Male reproductive organs consisted of testis, primary spermatic duct, spermatic gland, secondary spermatic duct, spermatophoric gland and spermatophoric sac. Histologically, the testis was testicular tubule type and male germ cells showed a layered arrangement. The primary spermatic duct was a tube connecting the testis and spermatic gland, and consisted with epithelial layer and connective tissue. The spermatic gland was located between the primary and secondary spermatic duct, and the epithelial layer was composed of epithelial cells and mucous cells. Mucous cells reacted blue in the AB-PAS (pH 2.5) reaction and purple in the AF-AB (pH 2.5) reaction. The secondary spermatic duct was a short tube connecting spermatic gland and spermatophoric gland, and folds were developed in lumen. The spermatophoric gland consisted of numerous tubular glands and secretory cells had eosinophilic granules. The spermatophoric sac was shape of pouch, folds were developed in lumen, and vacuolar secretory cells were present in the epithelial layer. The spermatophore was 83.5 mm long and consisted of cap thread in anterior portion, ejaculatory apparatus and cement body in medial portion, sperm mass in posterior portion.

A Convergence Study on the Effects of Improving Buckwheat Dietary Fiber in Mice with Hyperlipidemia and Oxidative Stress (고지혈증과 산화적 스트레스가 유도된 생쥐에서 메밀 식이섬유의 개선 효과에 대한 융합 연구)

  • Lee, Kwang Yeon;Bae, In Young
    • Journal of the Korea Convergence Society
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    • v.12 no.10
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    • pp.105-112
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    • 2021
  • The effect of buckwheat dietary fiber (BDF) as hypolipidemic and antioxidant agent were determined in C57BL/6 mice fed a high fat diet (HFD) with different doses of 500 (low, BDF-L) or 1,000 (high, BDF-H) mg/kg of body weight, compared with the HFD-diet control group (HFD). The negative control group (ND) was fed the basal diet. Body weights in the BDF-L and BDF-H groups were significantly decreased as compared to those in the HFD group (p<0.05). BDF also improved the lipid profile in a dose-dependent manner; serum lipid profiles and levels of insulin, glucose, and free fatty acid were significantly decreased in the BDF-L and BDF-H groups, whereas HDL-C and adiponectin significantly increased as compared to the HFD group (p<0.05). Meanwhile, BDF lowered serum malondialdehyde (MDA) in comparison with the HFD group (p<0.05). The results demonstrate that the intake of BDF might prevent obesity and its related metabolic disorders by inducing dyslipidemia and oxidative stress.

Fermentative Properties and Immunomodulating Activity of Low-sodium Kimchi Supplemented with Acanthopanax senticosus and Glycyrrhizae uralensis Extracts (가시오가피와 감초 추출물을 첨가한 저 나트륨 김치의 발효특성과 면역 활성능)

  • Yu, Kwang-Won;Suh, Hyung-Joo;Hwang, Jong-Hyun
    • The Korean Journal of Food And Nutrition
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    • v.25 no.4
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    • pp.878-887
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    • 2012
  • This study investigated the fermentative characteristics and immunomodulating activity in Kimchi added with various salts (salt replacement and herb-salt with Acanthopanax senticosus and Glycyrrhizae uralensis) for the reduction of Na concentration in Kimchi. Kimchi using a salt replacement and herb-salt showed a higher level of acidity (0.8~0.84%) than that of the control (0.7%) at 7-day fermentation. Kimchi using a salt replacement and herb-salt showed a lower level of salinity (1.72~1.98%) than that of control (2.3~2.57%) during fermentation. The growth of Lactobacillus spp. and Leuconostoc spp. recorded the highest level ($2.3{\times}10^8$ and $2.8{\times}10^6cfu/g$, respectively) in control at 6 day-fermentation. However, those levels in Kimchi prepared with salt replacement and herb-salt were $3.5{\sim}5.4{\times}10^8$ and $6.1{\times}10^6cfu/g$, respectively. It is assumed that the high level of acidity of Kimchi prepared with salt replacement and herb-salt was caused by the increase in the growth of Lactobacillus spp. and Leuconostoc spp.. When the macrophage stimulating activity of salt replacement kimchi (Salt-R kimchi) supplemented with hot-water extract from Acanthopanax sentisus (AS) or Glycyrrhiza uralensis (GU) was investigated on aging period, Salt-RA kimchi with AS 5% at 6 days (2.78-fold of saline control at $100{\mu}g/m{\ell}$) and Salt-RG kimchi with GU 5% at 9 days (2.02-fold) significantly increased compared to the Salt-RA kimchi without AS or GU. In addition, Salt-RAG kimchi with AS 3% and GU 3% improved the bitter taste of Salt-RA and potently stimulated the macrophage at 6 days (1.28-fold of Salt-R kimchi) even though its activity was lower than Salt-RA (5%, 1.39-fold).

Emulsifying Properties of Whey Protein Hydrolysates (유청 단백질 가수분해물의 유화특성)

  • 양희진;이수원
    • Food Science of Animal Resources
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    • v.23 no.1
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    • pp.63-69
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    • 2003
  • This experiment was carried out to study changes in solubility and emulsifying properties of whey protein. Whey protein hydrolysates were obtained from tryptic hydrolysis of whey protein concentrate at pH 8.0 and 37$^{\circ}C$ for 6 hours. Emulsifying activity of whey protein hydrolysate was highest at 4 hours of hydroysis and at 5.50% of DH. During hydrolysis of whey protein concentrate with trypsin, ${\alpha}$-lactalbumin was not easily broken down. But ${\beta}$-lactoglobulin was hydrolysed rapidly from the early stage of hydrolysis, producing several low molecular weight peptides, which have to participate in increasing emusifying activity. The solulbility of hydyolysates tended to increase depending on hydrolysis time; however, there was a gradual decrease after 5 hours. The hydrolysate had a minimum solubility near the isoelectric point range (pH 4∼5). The more hydrolysed the whey protein concentrates, the more soluble they are near the pl. They aye also more soluble above pH 6. Emulsifying activity of hydrolysates showed similar results to solubility. Creaming stability gradually increased when hydrolysis increased, increasing rapidly above pH 8 after 4 hours of hydrolysis.

Effect of Citrate and Phosphate on the Inhibition of Browning in Minimally Processed Potatoes (최소가공 처리 감자에 대한 Citrate 및 Phosphate의 갈변저해 효과)

  • Jung, Hur
    • Culinary science and hospitality research
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    • v.13 no.2
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    • pp.254-259
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    • 2007
  • The control of enzymic browning in potato slices by the use of citrate and phosphate buffer at different pH values and concentration was investigated. Minimally processed potatoes were stored at $5^{\circ}C$ and $20^{\circ}C$ followed by dipping in distilled water, citrate buffer (pH $3.0{\sim}5.0$) and phosphate buffer (pH $5.0{\sim}7.0$). The color characteristic was measured after storage at $5^{\circ}C$ and $20^{\circ}C$ for 24 hours. Treatment effectiveness was greatly improved by reducing pH and temperature. The citrate buffer was more effective than phosphate buffer in the browning inhibitory capacity. The citrate buffer (pH 3.0) showed the most anti-browning effect in this condition and more effective inhibition of browning by increasing concentration of treatment solution. The phosphate buffer (pH 5.0) treatment showed more effectiveness than concentration of 0.5 M of citrate buffer treatment.

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A Study on the Extratropical Cyclones in the North Pacific Ocean during the Winter Season for Safe Navigation of Ships (선박의 안전항해를 위한 겨울철 북태평양의 온대저기압에 관한 연구)

  • Ko, Nan-Young;Seol, Dong-Il
    • Journal of Navigation and Port Research
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    • v.44 no.6
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    • pp.447-452
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    • 2020
  • Extratropical cyclone in winter season is very important in safe operation of ships because it is a major cause of marine accidents due to its strong power. In this study, we used meteorological data, to analyze extratropical cyclones occurring near the 1st Pacific polar front from December 2019 to February 2020. The analysis results are as follows. During those three months, we recorded 41 extratropical cyclones, 8 of which were remarkably developed. The central pressure of the strongest cyclone was 947hPa. The highest number of cyclones were generated in the East P acific Ocean around J apan (16), followed by the areas around Korea, the East China Sea, and the southern Sea of J apan. The cyclones followed five major tracks with a common northeast pattern. We thus concluded that the optimal route for a ship encountering an extratropical cyclone in the North P acific in winter would be south of the cyclone's center traveling eastbound and north of the center traveling westbound.

Influence of Artificial Acid Rain on the Growth of Soybean Irradiated with Low Dose Gamma Radiation (저선량 감마선이 조사된 대두작물의 생육에 미치는 산성강우 효과)

  • Kim, Jae-Sung;Lee, Eun-Kyung;Lee, Young-Keun;Lee, Young-Bok
    • Korean Journal of Environmental Agriculture
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    • v.18 no.3
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    • pp.245-249
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    • 1999
  • This study was carried out to investigate the influence of artificial acid rain on the growth of soybean irradiated with the low dose gamma radiation. The growth patterns of Hwangkumkong and Bangsakong were not dependent on the acid rain treatment and the period of seed storage but the radiation dose. In Hwangkumkong, the optimal irradiation dose for the growth promotion was lower in the acid rain treatment group than the control group. The symptom of acid rain damage appeared broadly around pH 2.20, were higher in Hwangkumkong than in Bangsakong, and were more effective in the seeds of 1997 than 1995. But the damage symptom of Bangsakong was not dependent on the acid rain treatment and the irradiation of gamma radiaiton.

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A Study on Chemical Resistance of Cement Mortar Blended with Thermally Activated Diatomite containing Heavy Metals form EAF Dust (EAF Dust사의 중금속을 함침한 활성 규조토가 혼합된 시멘트 모르터의 내화학성에 관한 연구)

  • 류한길;임남웅;박종옥
    • Magazine of the Korea Concrete Institute
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    • v.9 no.1
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    • pp.143-151
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    • 1997
  • Chemical resistance of the cement mortar containing the Thermally Activated Diaomite(TAD) and H.M.(Heavy Metals) has been studied. The H.M.. extracted from EAF(Electrica1 Arc Furnace) Dust. were saturated with diatomite. The diatomite was then thermally activated at $750{\circ}C$ for 30minutes and powdeled. The powder was mixed with a portland cement on a weight basis from 0%. 2.5%. 5.0%. 10%. 20%. The optimum mixture. after those mixtures were subjected to compressive strength(7 and 28days) and leaching bchaviour of H.M.. was tested for its experiment on Wet/Dry cycles and chemical resistance(e.q. imrncrsion in 5%(Conc.) of H2S04, CaC12 and hlgSO4. It was shown that the cement, mortar containing 10% of' P.D. gave a rise to the remarkable increase in compressive strength. The compressive strength was generally decrease beyond the addition of 10% of P.D. The maximum $496kgf/cm^2$ of 28days compressive strength was acheiveti when 10% of P.D. was added to the cement mortar.

Design of H.264 deblocking filter for the Low-Power Portable Multimedia (저전력 휴대용 멀티미디어를 위한 H.264 디블록킹 필터 설계)

  • Park, Sang Woo;Heo, Jeong Hwa;Park, Sang Bong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.8 no.4
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    • pp.59-65
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    • 2008
  • This paper proposed a H.264 deblocking filter for the portable low-power multimedia. In H.264 deblocking filter, total 8 input pixels in filtering operations needs own filtering operation process respectively, and each filtering process has common structures for each filtering operation. By sharing common filter coefficients and registers, we have designed and implemented an smaller gated module, and moreover filtering operations are skipped on some or whole pixels what if we use some specific condition to operate filtering modules that need lots of operations. In the core of filtering modules, we achieve 33.31% and 10.85% gate count reduction compared with those of filtering modules of the conventional deblocking filter papers. The proposed low-power deblocking filter is implemented by using samsung 0.35um standard cell library technology, the maximum operationh frequency is 108MHz, and the maximum throughput is 33.03 frames/s with CCIR601 image format.

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