• 한국환경과학회지
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• 제15권8호
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• pp.785-797
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• 2006

The formation characteristics of trihalomethanes (THMs) and haloacetic acids (HAAs) were investigated in chlorination of raw water of different organic mallet characteristics. The samples used in this study were hydrophobic (N-HPO) and hydrophilic fraction (N-HPI) (which were concentrated and separated from Nakdong river water), and humic acid (HA) (which is known as a strong hydrophobic acid) as a reference organic matter, the specific UV absorbance (SUVA) of which was 2.19, 1.15 and 7.92, respectively. With increasing chlorine contact time, THMFP and HAAFP (the formation potential of THMs and HAAs) increased, but their increase was different depending on the organic mallet characteristics (i.e., for N-HPI, THMFP was higher than HAAFP, but the inverse result was obtained for N-HPO and HA and the ratio between them was greater for HA), and the mainly formed chemical species were CHCI$_3$ in case of THMs and dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) in case of HAAs for N-HPO and HA (and the ratios of CHCI$_3$ to total THMs and DCAA and TCAA to total HAAs for HA were higher than those for N-HPO), but for N-HPI, the ratio of brominated THMs was a little higher than that of CHCI$_3$ and the ratio of DCAA and TCAA to total HAAs was lower than that of N-HPO, although they are main chemical species in case of HAAs. Comparing THMFP and HAAFP with the increase in bromide concentration added with those in not adding it, the former increased greatly and its increase was higher for the organic mallet with stronger hydrophobicity, but the latter was lower for N-HPO and N-HPI and was similar for HA. The main chemical species with increasing bromide concentration were CHBt$_3$ in case of THMs regardless of organic matter characteristics, and dibromoacetic acid (DBAA) for N-HPO and N-HPI, DBAA and tribromoacetic acid (TBAA) for HA in case of HAAs. With increasing reaction temperature and pH, THMFP and HAAFP increased for the former, but for the latter, THMFP increased and HAAFP decreased, although the rate of increase or decrease was different with organic mallet characteristics.

• 한국식품영양과학회지
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• 제36권8호
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• pp.1022-1030
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• 2007

붉은 대게 가공부산물로 이용도가 낮은 자숙액을 이용하여 효소 가수분해물의 제조를 시도하였고, 아울러 이의 맛, 영양 및 건강기능에 대한 특성을 조사하였다. 붉은 대게 자숙액은 일반성분 및 안전성면에서 식품가공소재로 이용하여도 아무런 문제가 없었다. 1단 가수분해물의 경우 TCA soluble index(TSI), ACE 저해능 및 항산화능을 고려하는 경우 Alcalase로 2.0시간 반응시켜 제조하는 것이 가장 적절하였다. 붉은 대게 자숙액 유래 Alcalase 1단 가수분해물을 기질로 하여 Flavourzyme, Neutrase 및 Protamex로 각각 2시간씩 연속적으로 가수분해시킨 2단 가수분해물의 ACE 저해능 및 항산화능은 1단 가수분해물에 비하여 유사하거나 약간 우수하여 2단 가수분해의 필요성이 인정되지 않았다. 붉은 대게 자숙액에 비하여 이를 Alcalase 처리한 가수분해물의 경우 일반성분 및 색조는 차이가 없었으나, glutamic acid 및 aspartic acid와 같은 맛에 관여하는 유리아미노산의 경우 증가하였다. 붉은 대게 유래 Alcalase 처리 가수분해물의 아미노산 함량은 11,859.6 mg/100 mL이었고, 주요 아미노산으로는 glutamic acid(10.2%), proline(10.1%) 및 glycine (10.7%) 등이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권10호
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• pp.1460-1468
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• 2003

An experiment was conducted to quantify the flow of soluble non-ammonia nitrogen (SNAN) in the liquid phase of ruminal (RD) and omasal digesta (OD), and to investigate diurnal pattern in SNAN flow in OD. Five ruminally cannulated Finnish-Ayrshire dairy cows in a $5{\times}5$ Latin square design consumed a basal diet of grass silage and barley grain, and that supplemented with four protein feeds (kg/d DM basis) as follows: skimmed milk powder (2.1), wet distiller' solubles (3.0), untreated rapeseed meal (2.1) and treated rapeseed meal (2.1). Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 1.0 h interval during a 12 h feeding cycle. Both RD and OD were acidified, centrifuged to remove microbes and precipitated with trichloroacetic acid followed by centrifugation. The SNAN fractions (free amino acid (AA), peptide and soluble protein) in RD and OD were assessed using ninhydrin assay. Free AA, peptide and soluble protein averaged 60.0, 89.4 and 2.1 g/d, respectively, for RD, and 81.8, 121.5 and 2.5 g/d, respectively, for OD. Although free AA flow was relatively high, mean peptide flow was quantitatively the most important fraction of SNAN, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis. Diurnal pattern in flow of peptide including free AA in OD during a 12 h feeding cycle peaked 1 h post-feeding, decreased by 3 h post-feeding and was relatively constant thereafter. Protein supplementation showed higher flow of peptide including free AA immediately after feeding compared with no supplemented diet. There were no differences among protein supplements in diurnal pattern in flow of peptide including free AA in OD.

• Asian-Australasian Journal of Animal Sciences
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• 제8권2호
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• pp.135-138
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• 1995

Soybean meal was fermented by Aspergillus usami in order to reduce phytate content. Aflatoxin B1 was not detected in the fermented soybean meal. The contents of crude protein, crude fiber, ether extract and crude ash were slightly increased following fermentation with a concomitant reduction in nitrogen free extract. Though the fermentation partly degraded proteins in the soybean meal, there was small difference in amino acid composition between the soybean meal and the fermented soybean meal. The results showed that the fermentation did not affect nutritional value of protein in soybean meal. Approximately 55% of phosphorus extracted by trichloroacetic acid was inositol hexaphosphate (phytate) in the soybean meal. The content of inositol tetra to hexaphosphates was not detected in the fermented soybean meal. These results indicated that the fermentation almost completely eliminated phytate in soybean meal. Phytase activity was not detected in the unfermented soybean meal. However, the enzyme activity in the fermented soybean meal was 167.7 U/g. When the fermented soybean meal in supplemented in formula feeds, phytase in the fermented soybean meal might partly degrade the phytate in other ingredients in the digestive tract. The fermented soybean meal is possibly used as a phytate-free protein source of feed, which contains high available phosphorus.

• 한국동물학회지
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• 제27권4호
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• pp.199-212
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• 1984

대장균의 세포질내에 존재하는 단백질 분해효소(protease Ci)를 추출하여 그 성질을 조사하였다. 이 효소는 insulin, glucagon 및 bovine growth hormone을 분해시키나, bovine serum albumin, casein 및 globin 등은 분해시키지 않는다. 이 효소의 native 한 상태에서의 분자량은 120,000이며, 54,000 dalton의 동일한 2개의 subunit로 구성되어 있다. Protease Ci의 최적 pH는 7.5이며 등전점은 5.5이다. 이 효소는 o-phenanthroline에 의해 저해되며, $Mn^++나 Co^++$와 같은 metal 이온들에 의하여 활성화되므로 metalloprotease임을 알 수 있다. 이 효소는 p-hydroxymercuribenzoate에 의해서 크게 저해되나 sulfhydryl protease의 specific한 저해제인 Ep475와 leupeptin에 의해서는 영향을 받지 않는다. 대장균 세포내에서는 또 다른 insulin 분해효소 (protease Pi)가 존재하는데, 이 효소는 periplasm에 존재하므로 protease Ci와는 다르다.

• Environmental Analysis Health and Toxicology
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• 제12권3_4호
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• pp.23-29
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• 1997

The main reason of applying chlorination is to sterilize microbes existing in the drinking water treatment. But chlorination could lead to the formation of disinfection by-products (DBPs) by the reaction of free chlorine with humic substance in the water. Especially the DBPs including trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), and haloketones (HKs) exist in the tap water. The US environmental protection agency (US EPA) defines that trihalomethanes, dichloroacetic acid, trichloroacetic acid, and dichloroacetonitrile among DBPs are probable/possible human carcinogens. US EPA suggests maximum contaminant levels (MCLs) for THMs (80$\mu$g/L) and HAAs (60$\mu$g/L) in drinking water. In Korea, THMs in drinking water has been surveyed but DBPs in general has not been studied in drinking water practically. Therefore only THMs have been regulating as criteria compounds since 1990 but neither HAAs nor HANs. Researches on HAAs are yet to be found. HAA formation potentials(HAAFPs) have not been practiced. HAAs depends on the characteristics of water sources by chlorination. In this study, HAAFPs from three distinct sources were investigated by laboratory chlorination experiments. This study was performed to measure the level of HAAs in drinking water in Seoul area. At April 1996, after collecting the raw waters from the three sites with the different properties, the water samples were chlorinated at various conditions(pH 5.5, pH 7.0 and without pH adjustment) in the state of raw water to have 0. 5mg/L of residual chlorine concentration. And the raw water, treated water, and tap water of water treatment were collected to measure the HAAs concentration. The quantitative analysis of HAAs was conducted by US EPA methods.

• 한국환경과학회지
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• 제24권4호
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• pp.541-547
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• 2015

Formation of disinfection by-products (DBPs) including trihalomethans (THMs) and haloacetic acids (HAAs) from chlorination of six different species (Chlorella vulgaris, Scenedesmus sp., Anabaena cylindrical, Microcystis aeruginosa, Asterionella formosa and Aulacoseira sp.) of algal extracellular organic matter (EOM). The EOM characteristics evaluation of six algal species reaching at the stationary phase in the growth curve showed most of its SUVA254 showed below 1 and this means hydrophilic organic matter is much higher than hydrophobic organic matter. Chloroform formation potential (CFFP), dichloroacetic acid formation potential (DCAAFP) and trichloroacetic acid formation potential (TCAAFP) were mainly composed of THMFP and HAAFP in the EOM of various algal species. In the case of THMFP/DOC and HAAFP/DOC values, EOM of blue-green algae has appeared highest and EOM of green algae and diatom in order. THMFP/DOC was higher than HAAFP/DOC in EOM of blue-green algae. In comparison of formation potential by unit DOC composed of HAAFP in algal species EOM, DCAAFP/DOC was 1.5 times to 7.5 time higher than TCAAFP/DOC in the EOM of blue-green algae, while DCAAFP/DOC was found to be relatively high compared to TCAAFP/DOC in the EOM of green algae and diatom.

• 대한환경공학회지
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• 제28권11호
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• pp.1135-1140
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• 2006

국내 정수장에서 염소소독시 발생하는 소독부산물인 트리할로메탄(THMs), 할로아세틱에시드(HAAs)의 발생농도와 각각의 종별 분포현황을 조사하였다. 조사대상은 일반적인 정수처리공정으로 구성된 한강, 금강, 섬진강, 낙동강 수계의 1개 정수장씩 총 4개소였다. THMs의 발생농도는 평균 26.9 ppb, 최대 46.7 ppb, 최소 11.0 ppb였으며, $HAA_5$의 발생농도는 평균 25.4 ppb, 최대 57.1 ppb, 최소 9.7 ppb였다. 계절적으로는 동절기에 농도가 낮았고 하절기에 높았다. THMs의 종별 분포를 조사한 결과 클로로포름의 비율이 평균 77%로 가장 높았고 다음으로는 브로모디클로로메탄(20%)이 높게 검출되었으며, 브로모포름의 농도는 정량한계 미만이었다. $HAA_5$의 경우 디클로로아세틱에시드(DCAA)와 트리클로로아세틱에시드(TCAA)의 합이 $HAA_5$의 97%를 차지하는 것으로 조사되었다. 그러나 한강수계의 경우는 이 비율이 평균 90%로 다소 낮았으며, 특히 겨울철에 비율이 가장 낮았다. 한편, 하절기를 제외하고는 DCAA가 TCAA보다 높은 것으로 조사되었다.

• 대한환경공학회지
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• 제32권5호
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• pp.523-530
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• 2010

14종의 합성유기질소 화합물들에서의 염소 소독부산물 생성 특성을 조사한 결과, 단위 DOC당 THM 생성능은 $Br^-$첨가 유무에 관계없이 3-aminobenzoic acid, 2-aminophenol, aniline, anthranilic acid 및 4-nitroaniline에서 높게 나타났다. 단위 DOC당 HAA 생성능 조사결과, $Br^-$ 첨가 유무에 관계없이 단위 DOC당 THM 생성능과 유사한 생성특성을 보였으나 특이하게 p-nitrophenol에서 가장 높은 생성능을 나타내었으며, 생성된 HAAFP의 대부분이 TCAAFP로 나타났다. 단위 DOC당 HAN 생성능은 3-aminobenzoic acid, 2-aminophenol, aniline 및 anthranilic acid에서 $Br^-$ 첨가 유무에 관계없이 높은 생성능을 나타내었고 다른 합성유기질소 화합물들에 비해 aniline에서 높은 생성능을 보였으며, 반응성이 높은 4종의 합성유기질소 화합물들에서 생성되는 HAN 구성종의 대부분은 DCAN으로 나타났다. 단위 DOC당 chloral hydrate와 chloropicrin의 생성능을 조사결과에서 3-aminobenzoic acid와 2-aminophenol에서 생성능이 높은 것으로 나타났고, 전체적으로 10 $mg/{\mu}g$ 이하의 비교적 낮은 생성능을 보였다. 염소 소독부산물 생성능이 높은 6종의 합성유기질소 화합물들과 시판 humic acid에서의 $Br^-$ 첨가 유무에 따른 단위 DOC 당 총 DBP 생성능을 조사한 결과에서 $Br^-$를 첨가한 경우는 anilin e> anthranilic acid> 3-aminobenzoic acid> 4-nitroaniline> humic acid> p-nitrophenol> 2-aminophenol 순으로 나타났고, $Br^-$를 첨가하지 않은 경우는 anthranilic acid> aniline> p-nitrophenol> humic acid> 4-nitroaniline> 3-aminobenzoic acid> 2-aminophenol 순으로 조사되었다. 또한, aniline, anthranilic acid, 4-nitroaniline 및 p-nitrophenol의 경우는 염소와의 반응성이 아주 높은 것으로 조사되었다.

• Journal of Dairy Science and Biotechnology
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• 제33권4호
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• pp.237-245
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• 2015

본 연구는 원유로부터 면역효능이 우수한 젖산균 Streptococcus macedonicus LC743을 분리하였고, 이 균으로 제조한 모짜렐라 치즈와 상업균주로 제조한 모짜렐라 치즈에 대해 이화학적 특성을 비교시험하였다. S. macedonicus LC743을 이용한 치즈의 일반성분 결과, 수분 53.16%, 단백질 26.42%, 지방 20.52%였다. S. macedonicus LC743을 이용한 치즈의 질소화합물 중 수용성 질소는 0.384%, 비단백태질소 0.051%, 아미노태질소는 0.060 Nmg/g으로서 상업균주를 이용한 치즈에 비해 수용성 질소 및 아미노태질소의 함량은 적은 반면, 비단백태 질소 함량은 높았다. 각 치즈에 존재하는 유기산 분석 결과 상업균주로 제조한 치즈가 809.80 mg/mL로서 가장 많은 함량을 나타낸 반면, S. macedonicus LC743으로 제조한 치즈는 668.09 mg/mL로 가장 낮은 함량을 보였다. S. macedonicus LC743을 이용한 치즈의 총 아미노산은 Ctysteine을 제외하고는 모든 아미노산에서 상업균주를 이용한 치즈에 비해 높은 함량을 차지하였다. S. macedonicus LC743 균주로 제조된 모짜렐라 치즈는 상업용 스타터로 제조된 모짜렐라 치즈, 시중 제품 및 외국제품에 비해 면역분비능이 높은 것으로 나타났으며, S. macedonicus LC743 균주를 상업균주와 혼합하여도 면역활성능이 우수한 것으로 나타났다.