• Asian-Australasian Journal of Animal Sciences
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• 제17권9호
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• pp.1255-1259
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• 2004

The objective of this study was to evaluate the effects of halogenated compounds, organic acids, unsaturated fatty acids and their mixtures on in vitro methane production and fermentative characteristics of mixed rumen microorganisms. Agents used in two in vitro experiments were bromoethanesulfonic acid (BES) and pyromellitic diimide (PMDI) as halogenated compound, fumarate and malate as organic acid, and linoleic acid and linolenic acid as unsaturated fatty acid sources. Ruminal fluid collected from a Holstein steer fed tall fescue and concentrate mixtures was incubated at $39^{\circ}C$ for 48 h with addition of those materials. Single supplementation of halogenated compounds, organic acids or unsaturated fatty acids decreased in vitro methane production (p<0.05). The second experiment was designed to investigate effects of combination of one of halogenated compounds and either organic acids or fatty acids on methane production. Lower concentration of methane and lower A:P ratio were observed with PMDI compared with BES (p<0.01). In general medium pH, VFA, total gas and hydrogen production, and dry matter degradability were affected by addition of the same compounds. In addition, PMDI+malate treatment resulted in the highest molar proportion of propionate, and lowest A:P ratio and methane production (p<0.01). Hydrogen production was highest in PMDI+linolenic acid and lowest in BES+malate treatment (p<0.01). PMDI+malate combination was the most recommendable in reducing methane production without too much influence on digestibility under conditions of present studies.

• 한국연초학회지
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• 제6권1호
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• pp.84-93
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• 1984

Six kinds of sugars (Maltose, Sucrose, Glucose, Fructose, Mannose and Lactose) and four kinds of organic acids (Malic, Tartaric, Lactic and Citric) were added by 2-10% for the former and 0.2-1.8% for the later in quantitatively to the inferior quality of Flue-cured leaf tobaccos, and treated at 135$^{\circ}C$ for 10 minutes to examine the effect on deliveries of tar and nicotine in smoke, variation of smoke pH and smoking taste. The results obtained are as follows. Tar and nicotine deliveries in smoke of tobacco show a great reduction with 5-6% addition of sugars. Reduction of nicotine delivery was to be 19% with addition of Glucose. Tar in smoke was, however, increased by 5-8% with 4% addition of Sucrose or Lactose. On the other hand, 4% addition of Glucose and Fructose gave 1 % reduction of tar delivery, but the reduction rate became to be small with increase of adding quantity. The smoking taste by the addition of Glucose and Fructose tobacco was found to be milder than by the other sugars. Tar and nicotine deliveries show a decreasing trend with the addition of organic acid, and Tartaric acid, among the organic acids described above, had greater effect than the other acids. 1% addition of Tartaric acid gaves 10-11% reduction in tar and nicotine delivery, and a fall of smoke pH, from 6.40 to 6.05, was found. Smoking taste by the addition of Lactic and Tartaric acid had milder than the others. And heat treatment for 10 minutes at $135^{\circ}C$ gave also better on smoking taste. The addition of mixture of sugars and organic acids, (Glucose 4%+Lactic acid 0.8% + Tartaric acid 0.2%) and then the successive heat treatment for 10 minutes at $135^{\circ}C$ improved greatly the quality of Fluecured leaf tobacco, and nicotine were reduced to 16-29%, and pH was changed from 6.46 to 6.14.

• 한국응용과학기술학회지
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• 제20권1호
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• pp.64-71
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• 2003

Squid ink was added to the low salt fermented squid by 4% of concentration and ripened at 10$^{\cric}C$ for 6 weeks and at 20$^{\cric}C$ for 28 days. The effect of the squid ink on the non-volatile organic acids of low salt fermented squid were investigated. The results are as follows; The non-volatile organic acid in the salt fermented squid without addition of the squid ink was examined and the result showed that lactic and acetic acids were the major organic acids even if very small amount of citric and oxalic acids were detected. In the squid ink added to the low salt fermented squid, total quantity of non-volatile organic acid in the latter part of the ripening was lower than no treatment groups.

• Applied Biological Chemistry
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• 제41권4호
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• pp.241-245
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• 1998

Two oxidation states of chromium commonly occur in natural soil/water systems, Cr(III) and Cr(VI). The oxidized form, Cr(VI), exists as the chromate ion and is more mobile and toxic than Cr(III). Therefore oxidation of Cr(III) by various Mn-oxides in natural systems is a very important environmental concern. Organic substances can inhibit the Cr(III) oxidation by binding, Cr(III) strongly and also by dissolving Mn-oxides. Most of Cr(III) oxidation studies were carried out using in vitro systems without organic substances which exist in natural soil/water systems. In this study effect of organic acids - oxalate and pyruvate - on Cr(III) oxidation by $birnessite({\delta}-MnO_2)$ was examined. The two organic acids significantly inhibited Cr(III) oxidation by birnessite. Oxalate showed more significant inhibition than pyruvate. As solution pH was lowered in the range of 3.0 to 5.0, the Cr(III) oxidation was more strongly depressed. Addition of more organic acids reduced the Cr(III) oxidation mare extensively. Different inhibition effects by the organic acids could be due to their ability of reductive dissolution of Mn-oxides and/or Cr(III) binding. Organic acids dissolved Mn-oxide during the Cr(III) oxidation by the oxide, Dissolution by oxalic acid was much greater than that by pyruvate, and the dissolution was more extensive at lower pH. Inhibition of Cr(III) oxidation was parallel to the dissolution of Mn-oxide by organic acids. Although the effect of Cr(III) binding by organic acids on Cr(III) oxidation is not known yet, Mn-oxide dissolution by organic acids could be a main reason for the inhibition of Cr(III) oxidation by Mn-oxide in presence of organic acids. Thus oxidation of Cr(III) to Cr(VI) by various Mn-oxides in natural systems could be much less than the oxidation estimated by in vitro studies with only Cr(III) and Mn-oxides.

• 생명과학회지
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• 제22권10호
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• pp.1324-1329
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• 2012

본 연구의 목적은 organic acids를 첨가하여 in vitro 상의 반추위 발효성상과 반추위 내 메탄 억제에 미치는 영향에 대한 효과를 알아보고자 하였다. 반추위액은 순천대학교 부속목장의 반추위 cannula가 시술된 Holstein에서 채취하였고, organic acids는 반추위액과 버퍼의 혼합액에 첨가하여 배양하였다. 그 결과 pH 값은 lactic acid, malic acid 및 succinic acid첨가구에서 6.69에서 6.16 정도로, 대조구와 다른 첨가구보다 낮았다. 총 가스 발생량은 배양 48시간에 aspartic acid, malic acid 및 succinic acid첨가구에서 유의적(p<0.05)으로 높았고, 메탄 발생량은 lactic acid 첨가구에서 대조구보다 낮았다. 총 VFA와 propionic acid의 농도는 배양 12시간에 모든 첨가구가 대조구에 비해 높았다. 반추위 미생물 측정 결과에서는 Fumaric acid와 malic acid의 bacteria수가 대조구에 비해 유의적으로 증가하였으며(p<0.05), protozoa수는 유의적(p<0.05)으로 감소되었다. 이상의 실험 결과를 종합해 보면, organic acids의 첨가는 반추위 내 pH를 감소시키고 가스 발생량, 반추위 미생물 성장량 및 propionic acid 모두 증가시켰으며, 특히 lactic acid는 메탄생성을 억제하였다. 앞으로 Organic acid와 다른 메탄억제 물질과 혼합하여 반추위 내 메탄생성 억제에 관한 구체적인 연구가 필요한 것으로 사료된다.

• Macromolecular Research
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• 제17권1호
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• pp.14-18
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• 2009

The acceleration effect of various organic acids, such as methanesulfonic acid (MSA), ethanesulfonic acid (ESA), 4,4'-sulfonyldibenzoic acid (SDA), diphenylacetic acid (DPAA), and $\rho$-toluenesulfonic acid (TSA), on the rate of styrene bulk polymerization with 2,2,6,6-tetramethylpiperidinyloxy (TEMPO) and benzoyl peroxide (BPO) was investigated. The addition of organic acids significantly accelerated the rate. Among these organic acids, DPAA showed an efficient rate-accelerating effect with living nature of polymerization. When DPAA was used as a rate-accelerating additive for TEMPO-mediated living free radical polymerization (LFRP), the rate of polymerization was dramatically enhanced, the linearity of reaction kinetics was successfully maintained, and the polydispersity was effectively controlled.

• Journal of Ginseng Research
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• 제20권3호
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• pp.307-317
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• 1996

This study was undertaken to examine the effects of fresh ginseng addition on the chemical and sensory properties of dongchimi juice fermented under various conditions. The contents of free sugars in dongchimi juice during fermentation increased at the initial stage, but decreased at the palatable stage and then increased again thereafter. Free sugars were higher in dongchlml juice with 4% of ginseng addition than with Soye ginseng and without ginseng addition. Analyses of organic acid contents showed that all three groups contained relatively high amounts of citric, lactic and malic acids. It was also found that, as fermentation progressed, the amounts of tactic and acetic acids in- creased, while that of malic acid decreased at the palatable stage and increased again thereafter. Total saponins were highest in dongchimi juice fermented at 4$^{\circ}C$ with 4% of ginseng addition and panax atrlol ginsenosldes were found more than panaxadiol ginsenosides in dongchimi juice The results of sensory evaluation revealed that dongchimi juice prepared with the addition of $4^{\circ}C$ and 4% ginseng was lower in sour taste and moldy off flavor than the control, thus scoring high In total acceptability. Dongchimi juice with 4% of ginseng addition was best in most sensory characteristics.

• 한국축산식품학회지
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• 제31권5호
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• pp.710-718
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• 2011

The effects of organic acids mix (0.4%) and modified atmosphere packaging (MAP) on the storage quality of sliced bacon were investigated. Pork bellies were treated with or without organic acids at the curing stage. The organic acids mix comprised 35% sodium acetate, 25% salt, 15% calcium lactate, 11% trisodium citrate, 7% ascorbate, and 7% citric acid. The cured pork bellies were smoked and packaged with 50% $CO_2$ + 50% $N_2$ (50% $CO_2$-MAP) and 100% $N_2$ (100% $N_2$-MAP), and stored at $5^{\circ}C$ for 14 d. The 50% $CO_2$-MAP showed a higher pH value (p<0.05) up to 10 d, a lower protein deterioration (p<0.05) as measured by volatile basic nitrogen (VBN) from 6 to 14 d, and a higher color value of lightness (CIE $L^*$) compared to 100% $N_2$-MAP. The development of lipid oxidation measured by thiobarbituric acid reactive substance (TBARS) values seemed to be effectively controlled throughout the storage period in both 50% $CO_2$-MAP and 100% $N_2$-MAP regardless of the application of organic acids. The 50% $CO_2$-MAP inhibited the growth of aerobic and anaerobic bacteria (p<0.05) both in non-added and bacon added with organic acids mix. The 50% $CO_2$-MAP alone seemed to be effective in delaying the growth of bacteria since the use of organic acids mix gave no additional effects. The addition of organic acids mix lowered the pH value (p<0.05), effectively retarded the protein deterioration (p<0.05), and showed a higher color value of lightness (CIE $L^*$) value (p<0.05) and lower color value of redness (CIE $a^*$) value (p<0.05). In conclusion, 50% $CO^2$-MAP showed better quality and self-life of sliced bacon during storage. However, the beneficial effect of organic acids mix was not noticed in the concentration used in this experiment.

• 공업화학
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• 제32권2호
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• pp.190-196
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• 2021

저품질 석회석의 탈황 성능 개선을 알아보기 위해 초산, 젖산, 개미산 등 3종의 유기산 첨가제를 사용하여 기포형 반응기에서 탈황 반응을 수행하였다. 유기산이 첨가되지 않은 석회석 슬러리는 pH 5.2 이하에서 초기 탈황 효율의 저하가 일어났다. 반면, 유기산이 첨가된 석회석 슬러리는 pH 4.2~4.5에서 안정된 초기 탈황 효율을 나타내었다. 슬러리 pH 4 이하에서 유기산이 첨가된 석회석 슬러리의 탈황 성능은 유기산의 해리에 의해 생성된 음이온의 양과 연관될 수 있다. 슬러리 중 유기산의 음이온 양이 많으면 슬러리 pH의 완충 기능 저하가 급격히 일어나지 않았다. 이와 같은 결과들은 유기산의 산성도 및 해리도에 기인하였다. 3종의 유기산 첨가에 따른 저품질 석회석 슬러리의 탈황 성능 증가율은 초산(2.6%) < 젖산 (6.4%) < 개미산 (16.7%) 순으로 나타났다.

• 대한화학회지
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• 제41권9호
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• pp.471-482
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• 1997

기체크로마토그래피/질량분석법(GC/MS)을 이용하여 소변 내에 존재하는 유기산들을 동시에 분리 정량분석할 수 있는 최적의 분석조건을 확립하기 위해 액체-액체추출법을 이용하여 분리하였고 이 때 pH의 영향 및 역추출방법과 그리고 옥심화 과정 첨가의 효과를 알아보았다. 그 결과 옥심화 과정 없이 pH가 0.5일 때 회수율이 좋았고 RSD값은 0.3-12.4%로 가장 적었다. 역추출과정을 통하여 방해물질이 제거되어 15-16분대의 머무름 값을 갖는 몇가지 유기산 검출이 확실시 되었다. 이를 토대로 51종의 유기산들에 대한 검량곡선을 작성하여 한국 정상어린이(n=16) 요시료 중의 유기산 함량분포를 얻었다.