• Animal Bioscience
• /
• 제37권1호
• /
• pp.105-115
• /
• 2024

Objective: A study was conducted to determine the chemical composition of barley and co-products from barley, corn, and wheat produced in South-East Asia or Australia, and to test the hypothesis that production area or production methods can impact the chemical composition of wheat co-products. Methods: Samples included seven barley grains, two malt barley rootlets, one corn gluten feed, one corn gluten meal, one corn bran, eight wheat brans, one wheat mill mix, and four wheat pollards. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid hydrolyzed ether extract, ash, minerals, starch, and insoluble dietary fiber and soluble dietary fiber. Malt barley rootlets and wheat co-products were also analyzed for sugars. Results: Chemical composition of barley, malt barley rootlets, and corn co-products were in general similar across countries. Wheat pollard had greater (p<0.05) concentrations of tryptophan, magnesium, and potassium compared with wheat bran, whereas wheat bran had greater (p<0.05) concentration of copper than wheat pollard. There were no differences in chemical composition between wheat bran produced in Australia and wheat bran produced in Thailand. Conclusion: Intact barley contains more starch, but fewer AA, than grain co-products. There were only few differences in the composition of wheat bran and wheat pollard, indicating that the two ingredients are similar, but with different names. However, corn gluten meal contains more protein and less fiber than corn bran.

• Archives of Pharmacal Research
• /
• 제14권3호
• /
• pp.255-260
• /
• 1991

Chitinase was partially purified from Allium fistulosum L (green onion_. Protein fraction precipitated from ammonium sulfate was passed through CM-Sepharose and Sephacryl HR-200. The specific activity of the chitinase was 6.4 units/mg and total recovery was 6.3%. The analysis of the products from the digestion of N-acetychitohexaose indicated that chitinase was endo in action, with oligerms from N-acetylchitobiose to chitotetraose. N-Acetylglucosaminidase from the same species hydrolyzed oligomers obtained from chitinase reaction to lower oligosaccharides. These data demonstrated that chitinolytic system exists in green onion.

• 한국축산식품학회지
• /
• 제31권1호
• /
• pp.129-138
• /
• 2011

본 논문에서는 리보오스와 저염 및 저 Glu 소맥글루텐산 가수분해물을 기본 기질로 하여 기존의 시스테인, 메티오닌, 티아민 등의 전구체로 반응시킨 육류향과 이를 버섯분말 및 지질전구체 등으로 대체하여 반응시킨 육류향의 관능적 특성을 비교하여 천연 육류 향미제를 개발하고자 하였다. 기본 기질로 식물단백 가수분해물은 염농도에 따른 소맥글루텐 산 가수분해물과 저 Glu 소맥글루텐 산 가수분해물을 사용하였으며 향 특성을 검토하였을 때 염 7%의 저 Glu 소맥글루텐 산 가수분해물을 사용하는 것이 적합하였으며 황화물 채소로 마늘 분말을 기본 기질로 하였다. 기존의 synthetic meat flavor의 전구체를 omission test에 의해 검토하였을 때 시스테인은 육류향의 기여도가 컸으며 메티오닌과 티아민 및 레시틴은 영향이 적어 다른 소재로의 대체 가능성을 나타내었다. Natural meat flavor의 전구체로 효모 자가분해물 적용시 이취가 강하여 적합하지 않았으며 마늘 분말 대신 마늘 착즙 분말로 대체가 가능하였다. 버섯분말의 경우 표고버섯을 protease로 효소처리하여 건조시킨 분말이 육류향 생성에 적합하였으며 느타리버섯은 고유의 향긋한 향미가 감소되어 적합하지 않았다. 지질전구체의 경우 라드를 적용하였을 때 다른 지질에 비해 느끼한 향 특성이 적당하고 1%의 농도에서 육류향과 황내의 향 특성이 조화로웠다. 지질인 라드와 인지질인 레시틴을 첨가하여 비교하였을 때 레시틴 첨가와 라드와 레시틴의 혼합 첨가보다 1% 농도의 라드를 단독 첨가하는 것이 좋은 육류향을 생성하였다. 따라서 기본 기질로 소맥글루텐 산 가수분해물을 저염 및 저 Glu화 하였으며, 기존의 육류향 생성에 사용되었던 메티오닌 티아민 및 레시틴의 전구체를 마늘 착즙 분말과 버섯분말 및 라드로 대체하였을 때 상대적으로 전체적인 향의 강도는 낮았으나 느끼하고 짠향이 감소되어 부드러운 육류향을 생성할 수 있었다.

• Journal of Dairy Science and Biotechnology
• /
• 제38권1호
• /
• pp.1-18
• /
• 2020

Lactose intolerance is a pathophysiological phenomenon caused by a deficiency of the enzyme lactase present in human intestines. Changes in intestinal digestion and colon fermentation after the intake of lactose-containing products cause diarrhea and other clinical discomforts. Therefore, lactose intolerance can be easily ameliorated by consuming lactose hydrolyzed milk and dairy products. In the recent years, lactose-free dairy products have provided lactose intolerant consumers with several options, due to an improvement in the quality and an increase in the variety of products. Currently, the manufacturing of lactose-free products also represents the fastest growing sector in the dairy industry. This review, thus, aims to provide an overview of the current availability and prospects of lactose-free dairy products, and also discuss the potential benefits of the development of a variety of lactose-free dairy foods.

• 대한화학회지
• /
• 제44권1호
• /
• pp.24-29
• /
• 2000

요쿠르트는 항암 및 다양한 건강 증진효과를 나타내는 것으로 알려져 있다. 요쿠르트 유산균에 의하여 생성되는 다당류(polysaccharides)가 그러한 효과를 나타내는 것으로 믿어진다. 본 연구에서는 시중에 판매되는 요쿠르트 제품중 주요한 몇 가지를 선택하여 그 속에서 다당류를 추출하고 완전산분해하여 단당류 조성비를 결정하였다. 요쿠르트 제품을 원심분리 후, 거르고 1M 황산으로 완전 산가수분해한 후 중화시켜 당용액을 얻어내었다. 이 당용액으로부터 일정량을 분취하여 증발건조시킨 후 TMSl(trimethylsilylimidazole)로 유도체화시켜 GC/MS로 분석하였다. 이번 연구에서 요쿠르트의 단당류는 fructose와 glucose 그리고 galactose로 구성되었음을 확인하였으며, 요쿠르트 제품에 따라 각기 다른 단당류 조성비 결과를 주었다.

• 생명과학회지
• /
• 제8권5호
• /
• pp.497-503
• /
• 1998

GTase와 CDase를 함께 분비$\cdot$생산하는 B. stearother-mophilus KJl6 균주의 CDase를 ammonium sulfate 침전, DBAE-cellulose, Sephadex G-100 column chromatogra-phy, 및 FPLC로 수율 7%, 비활성 12.4 units/mg, 정제도 87.6배로 정제된 CDase를 얻었으며 SDS-PAGE 상 단일 band를 확인하였다. 정제된 CDase의 분자량은 약 68,000 dalton 이었고 활성 최적 pH와 온도는 6.0와 55$^{\circ}C$였다. pH 안정성은 5.5~8.5의 범위에서 비교적 안정하였으며, 온도 안정성은 5$0^{\circ}C$에서 2시간까지는 안정하였고, 7$0^{\circ}C$에서 1시간 전처리하여도 80% 이상의 잔존활성을 나타내었다. 효소 활성은 $Cu^{+2}$와 $Hg^{+2}$와 같은 금속이온과 p-chlorome-rcuribenzoate, N-bromosuccinimide, mercaptoethanol, dithiothreitol에 의해서 효소활성이 강하게 저해되었다. 기질에 대한 반응 특이성은 $\gamma$ -CD를 가장 잘 분해하였으며, 그 외에 soluble starch나 amylose, amylopectin 등의 기질도 잘 분해하나 이들의 분해속도는 $\gamma$-CD에 비해서는 늦었다. 이들 기질의 최종 분해산물은 maltose였으며, maltose는 거의 분해되지 않았다.

• 한국미생물·생명공학회지
• /
• 제10권4호
• /
• pp.259-265
• /
• 1982

Bacillus circulans F-2 $\alpha$-amylase에 의한 각종 oligosaccharide의 분해산물을 조사하고, Bacillus circulans F-2 $\alpha$-amylase, Bacillus amyloliquefaciens $\alpha$-amylase, Rhizopus niveus glucoamylase에 의한 각종 생전분의 분해율을 비교 검토한 결과를 요약하면 다음과 같다. 1. 공시 oligosaccharide중 Bacillus circuians F-2 $\alpha$-amylase는 maltose와 maltotriose를 분해시키지 못하였으나 meltotetraose이상의 oligosaccharide는 분해시켰다. maltotetraose, maltopentaose, maltoheraose, maltoheptaose, maltooctaose중 maltotetraose의 분해가 가장 미약하였다. 2. soluble starch, amylopectin, amylose, oyster glycogen중 oyster glycogen의 분해율이 약간 낮았다. 3. corn starch의 분해율은 진탕반응이 정치반응보다 높았으나 potato starch에 대하여는 효소의 종류에 따라 일정치 않았다. 4. corn, rice, arrowroot, high amylose corn, banana, sago, yam, potato starch에 대하여 Bacillus circulans F-2 $\alpha$-amylase가 Bacillus amyloquefaciems $\alpha$-amylase, Rhizopus niveus glucoamylase보다 월등하게 높은 분해율을 나타내었다.

• 한국미생물·생명공학회지
• /
• 제23권6호
• /
• pp.710-716
• /
• 1995

$\beta $-1, 4-D-arabinogalactanase isolated from alkalophilic Bacillus sp. HJ-12, approximate Mw 42 kDa, was generally stable in the range of pH 6-10 and below 50$\circ$C and its highest activity was observed at 60$\circ$C with pH 7-9. The isolated $\beta $-1, 4-D-arabinogalactanase specifically hydrolyzed $\beta $-1, 4-galactosyl linkage that is the major structure of soybean arabinogalactan (SAG) but not $\beta $-1, 3-galactosyl linkage of the other polysaccharides. K. was estimated as 0.67 mg/ml by the method of Hanes-Woolf plot. No metals and chemical reagents inhibited the enzyme activity but urea did. The active site of this enzyme assumed to be tryptophan residue. The hydrolysis products from SAG, assayed by gel chromatography, TLC and HPLC, were predominantly galactotetraose (Gal$_{4}$) and triose (Gal$_{3}$) with a small portion. $\beta $-1, 4-D-arabinogalactanase hydrolyzed ONPG as well as SAG, and the degree of hydrolysis of SAG was 15% which is lower than that by the other $\beta $-1, 4-galactanases from different sources. SAG treated with this enzyme resulted in the reduction of specific viscosity up to 70%.

• 한국환경과학회지
• /
• 제15권11호
• /
• pp.1061-1067
• /
• 2006

Photodegradation of endosulfan alpha, beta, and sulfate known as the most toxic substance among organochlorine pesticides by UV irradiation was studied at experimental conditions such as different pH aqueous solution and reaction time. The initial concentration of endosulfan alpha, beta, and sulfate in aqueous solution was 500 ppb, respectively. The experiment of photodegradation was conducted in a quartz reactor equipped with a low pressure mercury lamp (100 W, 240 nm). The samples were withdrawn from the photo reactor at intervals of 0, 10 min, 30 min, 1 hr, 2 hr, and 4 hr. Endosulfan sulfate was never hydrolyzed and photodegraded in wide range of pH. At pH 5 and reaction time (240 min), endosulfan alpha was photodegraded up to 67%. Both endosulfan alpha and beta were started to photodegrade at pH 6.5 with the lapse of time, resulting in approximately 99.9% and 87.2% of photodegradation efficiency, respectively. Furthermore, at pH 9, endosulfan alpha and beta was partially hydrolyzed and photodegraded to 99.5% at 120 min of reaction time. During the photolysis, any photo-products of endosulfan alpha, beta, and sulfate were not observed.

• 한국세라믹학회지
• /
• 제26권1호
• /
• pp.100-108
• /
• 1989

Aluminum hydroxides were prepared by the alkoxide hydrolysis method using Al-isopropoxide as a starting material and NH4OH as a catalytic agent. When Al-isopropoxide was hydrolyzed in a H2O-NH3 system, only Al(OH)3 was obtained over all pH values. However, AlOOH was formed besides Al(OH)3 when Al-isopropoxide was hydrolyzed in a H2O-NH3-isopropyl alcohol system. The AlOOH/Al(OH)3 ratio was increased as the isopropyl alcohol content was increased. The hydroxides, Al(OH)3 and AlOOH, obtained in this study and the commerical products, $\alpha$-Al2O3 and AlOOH were subjected to the carbothermal reduction and nitridation reaction to product AlN powder, using carbon black as a reducing agent under N2 atmosphere at various temperatures. AlN was synthesized from the obtained Al(OH)3 and the commercial AlOOH at 145$0^{\circ}C$, however, synthesized from the obtained AlOOH and the commercial alpha-alumina at 135$0^{\circ}C$. The temperature difference is assumed to be attributed to the reactivity of those powders. AlN powder prepared from the Al-isopropoxide was observed to have the narrower particle size distribution than that prepared from the commercial $\alpha$-Al2O3 or AlOOH.