• 미생물학회지
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• 제31권3호
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• pp.218-223
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• 1993

Conditions for the release and regeneration of protoplasts form Rhizopus oryzae and intergeneric protoplast fusion between Rhizopus oryzae and Aspergillus oryzae were studied. High yields of protoplast fusion between Rhizopus oryzae and Aspergillus oxyzae were studied. High yield of protoplasts from young germilings of R. oryzae were obtained by using lytic enzymes containing chitosanase (3 mg/ml), chitinase (3 mg/ml) and Novozym 234 (5 mg/ml). 0.5M glucose was used as the osmotic stabilizer and optimum pH of buffer was determined to be pH 7.5-8.0. Under these conditions, protoplasts were formed after about 3-4 hrs incubation. Approximately, 1.0%-4.9% of these protoplasts were formed after about 3-4 hrs incubation. Approximately, 1.0%-4.9% of these protoplasts regenerated on solid medium with a soft agar overlay. We have also carried out protoplasts fusion between R. oryzae and A. oryzae and have succeeded in obtaining three types of intergeneric fusants. In these experiments, 35% PEG-4000 and 10 mM CaCl$_{2}$ were used as fsogenic agents, and auxotrophic properties were used as a genetic marker to select fusants. Complementation frequency be protoplasts fusion of A. oxyzae and R. oryzae was 4.4% * 10$^{-5}$ . The fusant strains of the first type were prototrophs showing an Aspergillus type morphology with dark-yellow sporulation, those of the second type were also Apergillus type morphology but showed no sporulation. And the strains of the third type stopped growing when fusion products grown on regeneration minimal medium were transferred to fresh minimal medium. The formation of fusion products was observed by fluorescent vital stains for complementary labelling of protoplats from R. oryzae and A. oryzae. Rhodamine 6G and fluorescein diacetate wer useful complementary vital stains of Rhizopus and Aspergillus protoplasts for visualization of requency and type (dicell, multicell) of fusion.

• 한국식품과학회지
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• 제28권5호
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• pp.870-876
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• 1996

가시발새우 껍질을 부가가치가 높은 자원으로 활용하기 위하여, 이들로부터 키틴과 키토산을 제조하여 물리화학적 특성을 살펴 보았다. 가시발새우 껍질에서 추출한 키틴의 일반성분은 질소 6.84%, 지방 0.57%, 회분 0.32%였으며, 수율은 15.7%였다. 키토산은 질소함량이 7.52%였으며 지방과 회분함량은 각각 0.13%와 0.33%였다. 그리고 탈아세틸화도는 67.5%, 분자량은 $9.1{\times}10^5$이었으며 수율은 75%를 나타내었다. 키틴 및 키토산의 잔류 아미노산은 각각 2.64mg/g과 1.39mg/g 검출되었고, 그 중 lysine이 가장 높게 나타났다. 한편 키틴과 키토산의 IR 스펙트럼과 고체상태 $^{13}C-NMR$ 스펙트럼 data는 분자구조를 확인하는데 도움이 되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권4호
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• pp.486-495
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• 2012

Twenty four periparturient cows were used to determine the effects of DCAD on acid-base balance, plasma and urine mineral concentrations, health status, and subsequent lactation performance. Each group of 12 cows received either a diet containing -100 DCAD or +100 DCAD for 21 d prepartum. Both anionic and cationic groups were divided into two groups, one received a +200 DCAD and the other +400 DCAD diet for 60 d postpartum. Prepartum reduction of DCAD decreased DMI, urinary and blood pH, urinary concentrations of Na or K and increased plasma and urinary Ca, Mg, Cl and S. Also cows fed -100 DCAD diet consumed the most dry matter in the first 60 d after calving. Postpartum +400 DCAD increased milk fat and total solid percentages, urinary and blood pH and urinary Na and K concentrations, but urinary Ca, P, Cl and S contents decreased. Greater DMI, FCM yields were observed in cows fed a diet of +400 DCAD than +200 DCAD. No case of milk fever occurred for any diets but feeding with a negative DCAD diet reduced placenta expulsion time. In conclusion, feeding negative DCAD in late gestation period and high DCAD in early lactation improves performance and productivity of dairy cows.

• 한국지역사회생활과학회지
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• 제21권4호
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• pp.481-488
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• 2010

The objective of this study was the development of the preparation method of fermented turnip juice. The yields and soluble solids of fermented turnip juice were 41.2, 52.8, 56.4 and 57.4%, and 34.3, 42.4, 48.6 and 54.7 $^{\circ}Brix$ with 40, 60, 80 and 100% addition rate of turnip quantity, respectively. The major organic acids in turnip juice were succinic acid, isobutyric acid and fumaric acid, and these organic acids were decreased after fermentation. On the other hand, lactic acid, formic acid, acetic acid, propionic acid and butyric acid were produced during the fermentation. Soluble solid and pH value in fermented turnip decreased by time-dependently. Free radical scavenging activity was increased by fermentation of turnips and nitrate scavenging effects were the highest in pH 3 and increased with adding Omija or Japanese apricot. The best preparation method of fermented turnip juice was fermentation at $24^{\circ}C$ 12-15 days after adding 40% of sucrose to total quantity. As adding Omija, organic acid contents were increased and sensory evaluation was improved in fermented turnip juice.

• 한국작물학회지
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• 제41권1호
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• pp.109-114
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• 1996

논토양에서 경운방법과 시비수준을 달리하여 화성벼를 5년간 동일포장에서 재배했을 때 벼수량과 토양특성 변화를 조사분석한 결과는 다음과 같다. 1. 기종별 경운효율은 경운기 로타리구가 74.8％로서 제일 높고 트랙타 경운구가 59.0％로서 가장 낮았다. 2. 벼 이앙후 무경운구의 감수심이 가장 많았으며 벼 생육중기보다는 생육초기에서 많았다. 3. 벼 수량은 무경운 관행시비에 비해 경운기 로타리 농토배양시비구가 가장 많은 17％가 증수되었고 경운처리를 하므로서 벼수량은 6∼17％ 증수되었다. 연차간에는 2연차에서 수량이 가장 많았고 4년차에서 가장 낮았다. 4. 경운하지 않은 무경운구의 용적밀도와 고상률이 가장 높았으며 토양의 화학성 변화는 처리간에 일정한 경향이 없었다.

• 한국식품과학회지
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• 제20권3호
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• pp.441-446
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• 1988

마른 멸치를$0{\sim}0.5N$의 NaOH 용액과 함께 마쇄한 뒤 $60^{\circ}C$에서 $0{\sim}6$시간까지 처리시키면서 원심분리 하여 얻어진 멸치 추출액의 고형분 수율과 몇몇 물리적 품질과 관능적 품질의 변화를 측정하였다. 그 결과 NaOH의 농도와 처리시간이 증가 할수록 고형분과 단백질의 수율은 증가하였으며 고유점도는 급격히 증가하여 최고 값에 도달하였다가 서서히 감소하였다. Hunter값으로 표시된 추출액의 색의 변화는 'L'값이 반응초기에 증가하여 색이 밝아졌다가 그 후 강소하였으며 'a'값과 'b'값은 약간 증가하는 경향을 보여 주었다. 알칼리 처리가 멸치추출액의 맛과 냄새에 미치는 영향은 알칼리 농도와 처리시간이 가할수록 맛과 냄새의 강도가 현저히 상승 하였으며 맛과 냄새 중 소라맛, 쓴맛 그리고 소라냄새, 바닷물 냄새에서 특히 높은 강도를 보여 주었다.

• Journal of Photoscience
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• 제5권3호
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• pp.105-109
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• 1998

By using the liquid -phase-deposition (LPD) process, which has a potetnial of preparing organic inorganic composite materials, samples doped with benzo[f]quinoline (BfQ)into silica thia films wre prepared. We observed the fluorescene and fluorescene excitation spectra of the samples, as well as the fluorescence lifetimes and time-resoluved fluorescence spectra. The comparison of thefluorescence spectra in pH-controlled buffer solutions yields the results that the dominant species of BfQ in the LPD silica films is a protonated one. The fluorescence band assigned to a hydrogen-bonded species was observed on the samples prepared from the dipping solutions of 3 and 2 M hexafluorosilicic acid. The band assignment was confirmed by the fluorescence lifetime measurement. The FT-IR M hexaflurosilicic acid. The band assignment was confirmed by the flurescence lifetime meausurement. The FT-IR data proved the existence of included water in silica films prepared from the LPD process. The appearance of the band corresponding to the hydrogen-bonded species within LPD silica phases was explained by the proesence of included water. Depending on the preparation conditions of LPD silica films, the band assigned to protonated species shows bad shifts in a wavenumber region between the peak of hydrogen-bonded and typical protonated species. This implies that there is some distribution of steric conformation of protonated species of BfQ interacting with adsorbing sites of LPD silica. The time -resolved fluorescence spectra suggest that some relaxation process is involved in the conformation of BfQ doped into the solid phase of LPD silica.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.947-953
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• 2011

A fungal strain, Aspergillus terreus strain GA2, isolated from an agricultural field cultivating sweet sorghum, produced feruloyl esterase using maize bran. In order to obtain maximum yields of feruloyl esterase, the solid state fermentation (SSF) conditions for enzyme production were standardized. Effective feruloyl esterase production was observed with maize bran as substrate followed by wheat bran, coconut husk, and rice husk among the tested agro-waste crop residues. Optimum particle size of 0.71-0.3 mm and moisture content of 80% favored enzyme production. Moreover, optimum feruloyl esterase production was observed at pH 6.0 and a temperature of $30^{\circ}C$. Supplementation of potato starch (0.6%) as the carbon source and casein (1%) as the nitrogen source favored enzyme production. Furthermore, the culture produced the enzyme after 7 days of incubation when the C:N ratio was 5. Optimization of the SSF conditions revealed that maximum enzyme activity (1,162 U/gds) was observed after 7 days in a production medium of 80% moisture content and pH 6.0 containing 16 g maize bran [25% (w/v)] of particle size of 0.71-0.3 mm, 0.6% potato starch, 3.0% casein, and 64 ml of formulated basal salt solution. Overall, the enzyme production was enhanced by 3.2-fold as compared with un-optimized conditions.

• Journal of Microbiology and Biotechnology
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• 제23권3호
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• pp.364-374
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• 2013

Monacolin K and yellow pigment, produced by Monascus sp., have each been proven to be beneficial compounds as antihypercholesterolemic and anti-inflammation agents, respectively. However, citrinin, a human toxic substance, was also synthesized in this fungus. In this research, solidstate fermentation of M. purpureus TISTR 3541 was optimized by statistical methodology to obtain a high production of monacolin K and yellow pigment along with a low level of citrinin. Fractional factorial design was applied in this study to identify the significant factors. Among the 13 variables, five parameters (i.e., glycerol, methionine, sodium nitrate, cultivation time, and temperature) influencing monacolin K, yellow pigment, and citrinin production were identified. A central composite design was further employed to investigate the optimum level of these five factors. The maximum production of monacolin K and yellow pigment of 5,900 mg/kg and 1,700 units/g, respectively, and the minimum citrinin concentration of 0.26 mg/kg were achieved in the medium containing 2% glycerol, 0.14% methionine, and 0.01% sodium nitrate at $25^{\circ}C$ for 16 days of cultivation. The yields of monacolin K and yellow pigment were about 3 and 1.5 times higher than the basal medium, respectively, whereas citrinin was dramatically reduced by 36 times.

• Preventive Nutrition and Food Science
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• 제13권3호
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• pp.212-218
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• 2008

We extracted red ginseng with various alcohol concentrations and evaluated total carbohydrate, uronic acid, polyphenols compounds and ginsenoside contents, and yields of alcohol extract. The water extraction (0% alcohol extraction) showed a high level of total carbohydrate content. 10% and 20% alcohol extraction showed the highest uronic acid contents (7,978.8 and $7,872.7\;{\mu}g/mL$ of extract, respectively). The efficiency order of the red ginseng extract (RGE) preparations in liberating polyphenols was: $0{\sim}50%$ alcohol${\geq}\;60%$ alcohol> $70{\sim}90%$ alcohol. Solid contents in RGE were decreased with increased alcohol concentration; the same tendency as with the results of total carbohydrate content. Total ginsenoside contents in $20{\sim}50%$ alcohol extracts showed similar levels ($442,962.9{\sim}47,930.8\;{\mu}g/mL$ of extract). Water extraction showed the lowest ginsenoside content ($14,509.4\;{\mu}g/mL$ of extract). The ginsenoside contents at above 60% alcohol were decreased with increased alcohol concentration. Generally, ginsenoside (Rg2, Rg1, Rf, Re, Rd, Rb2, Rc and Rb1) contents were increased with increased alcohol concentrations. However, Rg3 content was decreased with increases in alcohol concentration.