• Applied Biological Chemistry
• /
• v.42 no.3
• /
• pp.193-198
• /
• 1999

The optimal culture condition of Bacillus sp. P16 was investigated for production of an extracellular endo-splitting chitosanase. The best carbon and nitrogen sources for the chitosanase production were chitosan and tryptone, respectively. The best condition for the maximum activity was at $37^{\circ}C$ in a medium containing 0.5% powdered chitosan, 1% tryptone, and 1% NaCl(at initial pH 7.0) in a rotary shaker(200 rpm). In a jar fermenter, the culture duration shortened to $6{\sim}12$ hr for maximum activity and the enzyme activity increased about 100% compared with that of flask culture.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.11 no.4
• /
• pp.13-16
• /
• 1982

The hydrolytic conversion of sawdust was studied by sulfuric acid-enzymatic and sodium hydroxide-enzymatic treatments. Sugars were identified by paper chromatography and quantified colorimetrically. Sawdust yielded dextrose and xylose in concentrations ranging from 3.01 to 3.64 and 3.48 to 6.61 grams per 100g. Under optimum conditions, the total concentration of sugars was 10.7 grams per 100 grams.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.4
• /
• pp.635-641
• /
• 2000

In order to utilize the protein source from a fish proessing by-product, cod was hydrolyzed with various enzymes such as tuna pyloric caeca crude enzyme (TPCCE), a-chymotrypsin, trypsin, papain and pronase E. The TPCCE hydrolysate acquired the highest sensory properties on taste, odor and color. The resultant cod rfame protein hydrolysate (CFPH) which was hydrolyzed with TPCCE, was separated through a series of ultrafiltration membranes with molecular weight cut-off (MWCO) of 30, 10, 5 and 1 kDa, and four types of permeates in cluding 30 K (permeate from 30 kDa membrane), 10 K (permeate from 10 kDa membrane), 5 K (permeate from 5 kDa membrane) and 1 K (permeate from 1 kDa membrane) were obtained. The natural sauces were prepared with 30 K, 10 K, 5 K and 1 K hydrolysate, and the sauce prepared with 1 K hydrolysate was the best score in sensory evaluations. In addition the mixed sauce prepared with 1 K hydrolysate and commercial soy sauce was similar to commercial sauce in sensory properties. These results suggest that the mixed sauce would be utilized as the substitute of acid-hydrolysis sauce.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.114.2-114.2
• /
• 2010

Fisher-Tropsch 반응을 통하여 생성되는 왁스는 황 또는 질소 성분을 포함하지 않으며 또한 방향족 및 중금속 성분이 없기 때문에 청정 수송유로써 사용이 가능하다는 장점이 있다. 그러나 Fisher-Tropsch 왁스는 그 분자량이 매우 큰 사슬형 탄화수소이기 때문에 수소첨가 분해반응을 통하여 중질유 range의 탄소수를 갖는 탄화수소로의 전환 기술이 반드시 필요하다. 이러한 수소첨가 분해반응에 사용되는 촉매는 강한 산점을 지니고 있는 양이온 교환 지르코니아가 대표적이라 할 수 있는데 최근 들어 강한 산점과 높은 산밀도, 그리고 기공의 모양과 크기에 따라 특정 반응이 제어되거나 활성화되는 형상선택성을 가지고 있기 때문에 다양한 반응에 촉매로 사용되는 제올라이트에 Pt 등의 귀금속을 담지한 촉매를 사용하여 Fisher-Tropsch 왁스의 전환율 및 중질유분의 선택도를 높이는 기술에 대한 연구가 활발히 진행되고 있다. 따라서 본 연구에서는 다양한 제올라이트 촉매에 귀금속을 담지하여 촉매를 제조하고 1L 급 고압 배치형 반응기를 이용하여 Fisher-Tropsch 왁스의 수소첨가 분해반응에 의한 중질유 제조 실험을 수행하고 그 결과를 고찰하였다.

• Korean Journal of Microbiology
• /
• v.24 no.4
• /
• pp.389-393
• /
• 1986

From the soil and river samples, some bacterial strains degrading chlorinated aromatic hydrocarbons were isolated and identified. Of the isolates, seven strains of Pseudomonas sp. harbouring plasmids were selected for their prominent degradative ability to 2-methyl-4-chlorophenoxyacetic acid. By agarose gel electrophoresis and curing experiment it was found that the genes for 2-methyl-4-chlorophenoxyacetic acid degradaiton were encoded on the plasmids in these selected strains. Antobiotic resistance and degradative ability for other herbicides of the strains were tested.

• Korean Journal of Food Science and Technology
• /
• v.23 no.1
• /
• pp.62-67
• /
• 1991

The characteristics of Tongjinbyeo(Japonica) and Samgangbyeo($J{\times}Indica$) rice starches including physicochemical properties, differential scanning calorimetry and enzymatic digestion of lintnerized starches were investigated. Degree of hydrolysis of Tongjinbyeo starch with 2.2N HCI for 48 hr was higher than that of Samgangbyeo starch. Apparent first order reaction of starches was slow reaction for first period, and fast reaction second period on the datum point of acid treatment 24 hr. Absorbance at ${\lambda}_{max}$ and 680 nm, and ${\lambda}_{max}$ of iodine stained starch and amylose content decreased upon acid treatment. But water binding capacity, swelling power and solubility considerably increased as hydrolysis progressed. Relative crystallinity of two starches increased with acid treatment, and that of Tongjinbyeo starch was higher than that of Samgangbyeo starch. Differential scanning colorimetry(DSC) data continuously decreased for lintnerization periods, and those of Tongjinbyeo starch have higher than those of Samgangbyeo starch. The onset temperature of starch by DSC continuously decreased by treatment, but conclusion temperature increased until 24 hr and then decreased. The enthalpy for gelatinization decreased for both starches. Degree of hydrolysis of lintnerized Tongjinbyeo starch with glucoamylase was slightly higher than that of Samgangbyeo starch.

• Korean Journal of Food Science and Technology
• /
• v.21 no.1
• /
• pp.1-8
• /
• 1989

Ten cultivars of malting barley grown at four locations were malted and assayed for six enzymes involved in the degradation of nucleic acids. Among these enzymes were deoxyrinonuclease, ribonuclease, phosphodiesterase, 3'- and 5'- nucleotidases and phosphomonesterase. Activities of all enzymes in five-day malts were significantly affected by variety and location of growth. The average levels of ribonuclease, deoxyribonuclease, 3'-nucleotidase and 5'-nucleotidase of 80 five-day malts were 11.2, 5.7, 5.6 and 1.2 units per gram of malt, respectively. Six-rowed barley malts contained higher levels of deoxyribonuclease, phosphodiesterase and 3'-nucleotidase than those of two-rowed barley malts, while two-rowed barley malts contained significantly higher ribonuclease levels than those of six-rowed barley malts.

• Korean Journal of Food Science and Technology
• /
• v.14 no.3
• /
• pp.236-243
• /
• 1982

In order to remove the high content of malic acid (0.48%) in freshly fermented apple wine by applying malo-alcoholic fermentation(MAF) using malate-decomposing yeasts, Schizosaccharomyces japonicus var. japonicus or Schizosaccharomyces pombe, some factors which influenced malic acid decomposition in apple wine by malate-decomposing yeasts were investigated. By incubating the apple wine with these yeasts, 80% of initial malic acid was decomposed in 13 days at $20^{\circ}C$, whereas only 32% reduction in malic acid was observed in 40 days when MAF was not induced. For malic acid decomposition, Schizosaccharomyces pombe was superior to Schizosaccharomyces japonicus var. japonicus in natural medium such as apple wine, whereas Schizosaccharomyces japonicus var. japonicus was superior to Schizosaccharomyces pombe in synthetic medium. The optimum temperature for the MAF using these yeasts was between $20\;to\;30^{\circ}C$ and no adverse effect was detected by the addition of $SO_2$ up to 200ppm. Additions of $Mg^{2+}$ or certain amino acids such as alanine, aspartic acid to the wine could enhance the composition of malic acid.

• KSBB Journal
• /
• v.15 no.1
• /
• pp.72-75
• /
• 2000

The hydrolysis characteristics of each fatty acid composing the fish oil by means of the lipase from Candida cylindracea was investigated. The saturated fatty acids, C14:0, C16:0 and C18:0, and the unsaturated fatty acids with one double bond, C16:1, C18:1(n-7), C18:(n-9), C20:1 and C22:1 were more easily hydrolyzed than the $\omega$-3 polyunsaturated fatty acids. when the number of carbon of the $\omega$-3 fatty acids was same but that of double bond was different, the hydrolysis of the $\omega$-3 fatty acids having lower number of double bond was more rapidly carried out. When the degree of polyunsaturation was same but the number of carbon was different, the lipase acted more rapidly upon the $\omega$-3 fatty acids with lower number of carbon. Docosahexaenoic acid(DHA) was most highly concentrated in the glyceride mixture after 120hr hydrolysis among the various $\omega$-3 polyunsaturated fatty acids. The weight percentage of DHA to the $\omega$-3 fatty acids in the fish oil was 31.87% but that in the glyceride mixture after 120hr hydrolysis was 51.89%.

• The Korean Journal of Food And Nutrition
• /
• v.22 no.4
• /
• pp.639-643
• /
• 2009

In this study, the antineoplastic effects of chitosan hydrolysates were assessed. The chitosan hydrolysates showed no cytotoxicity in in vitro trials using the normal cell line, Vero E6(Africa green monkey kidney cells). The $IC_{50}$ value of the chitosan hydrolysates on Vero E6 was 1,107.95 ${\mu}g/m{\ell}$. The hydrolysates exhibited in vitro antineoplastic activity in five human tumor (lung carcinoma, bladder carcinoma, colon carcinoma, stomach carcinoma, breast carcinoma) cell lines. The $IC_{50}$ values of the hydrolysates on A549, J82, SNU-C4, SNU-1, and ZR75-1 cells were 421.06, 417.99, 445.54, 380.65 and 460.49 ${\mu}g/m{\ell}$, respectively.