• Clean Technology
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• v.29 no.2
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• pp.95-101
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• 2023

An experiment was conducted to produce vaterite-type precipitated calcium carbonate from waste oyster shells in order to use them as recyclable resources. Calcined oyster shells containing calcium oxide as their main component were prepared at a temperature of 800℃ for 24 h. The oyster shells were dissolved in nitric acid or hydrochloric acid solution to make 0.1 M calcium nitrate or calcium chloride aqueous solution, and a carbonation reaction was performed using a 0.1 M sodium carbonate aqueous solution under various experimental conditions, which included varying the amount of aspatic acid additive, the amount of NH₄OH added, the reaction time, the reaction temperature, the stirring speed, and the type of dissolved acid. The XRD, SEM, and size distributions were analyzed and the vaterite content was calculated. Spherical precipitated calcium carbonate with a vaterite content of 95.9% was synthesized by adding 0.1 mol aspatic acid/1 mol CaO and 2 cm³ of NH₄OH, and reacting for 1 h at 25℃ while stirring at 600 rpm. The average particle diameter was found to be 12.11 ㎛. Calcium carbonate contatining high vaterite is used as high value added calcium carbonate for medical, food, inke additiver, etc.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.875-884
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• 2011

The purpose of this study was to examine the qualities of optimized muffins with germinated brown rice soaked in mycelial culture broth of Phellinuslinteus (GBRP) using response surface methodology. Firstly, general compositions of optimized muffins with GBRP were higher than that of control and total sugar contents were similar. However, the total free amino acid and constitutional amino acid contents except for GABA were lower than those of control. Starch hydrolysis in control was higher than in optimized muffins with GBRP, whereas protein digestibility and protein efficiency ratio were not. The weights of optimized muffins with GBRP were higher than that of control (p<0.01), whereas height (p<0.01) and pH (p<0.001) were similar. The hardness (p<0.05) and chewiness (p<0.05) of optimized muffins with GBRP were higher compared to control; adhesiveness, springiness, and gumminess were similar, but cohesiveness (p<0.01) was not. The flavor (p<0.05) and taste (p<0.01) of optimized muffins with GBRP were higher than those of control; appearance, texture and overall acceptability were similar, but color (p<0.05) was not. The total polyphenol contents (p<0.01), DPPH radical scavenging activity (p<0.01), and superoxide dismutase-like activity (p<0.05) of optimized muffins with GBRP were higher than those of control, but nitrite scavenging activity was similar.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 1997.06b
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• pp.11-12
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• 1997

니트로소디메틸아민이 발암성 물질이라는 것이 1954년 Barnes와 Magee에 의해 발견된 이래 이것이 지금까지 학자들에게 관심의 대상이 되고 있는 이유는 발암력이 강하여 극미량으로도 생체내에 암을 유발시킬 수 있을 뿐만 아니라, 대부분의 발암성 물질이 신체의 특정기관에 발암작용을 나타내는데 비해 이 물질은 신체의 여러 부위에 암을 유발시킬 수 있다는 점 그리고 이 물질이 햄, 소시지, 베이컨, 알코올음료, 김치 및 어류 가공품 등 어려 가지 식품에 널리 분포되어 있다는 사실 등을 들 수 있다. 니트로소 화합물은 구조로 보아 티트로소아민과 니트로소아미드로 구분되는데 전자는 제 2급 아연이 산화질소 유도체와 반응하여 생성된 니트로소 유도체이과 후자는 오소, 아미드 등이 치환된 니트로소 유도체로서 화학적인 성질이나 생물학적인 작용이 상이하다. 즉 니트로소아민은 식품에서 안정한 화합물인 반면에 대부분의 니트로소아미드는 불안정하다. 지금까지 연구된 바에 의하면 3백 여종의 니트로소 화합물에 대하여 동물실험을 행한 결과 발암성이 90% 이상 인정되었다. 식품 중 니트로소 화합물의 전구물질 중 질산염과 아질산염은 식품의 가공 저장 및 조리과정 중 니트로화의 된 전구물질인데 이는 육가공품의 색소고정, Cl. Botulinum에 의한 식중독 방지 및 풍미의 향상을 위하여 수 세기 동안 식품첨가제를 사용되어 왔으며, 유럽이나 미국 등지에서는 아직도 육가공품에 아질산염의 첨가가 논란의 대상이 되고 있다. 식품 중 니트로소 화합물에 대한 북유럽 식품 3천여 점을 분석한 결과 검출된 니트로소 화함물은 니트로소디메틸아민이 대부분이며 맥주에서 66%로 검출률이 가장 높았고 다음으로 염지육 및 치즈의 순 이었다. 조리한 일본산 해산 식품 중에 니트로소디메틸아민이 최고 313$\mu$g/kg, 캐나다산 해산 건조 식품에서는 67$\mu$g/kg, 홍콩산 염건어에는 1,400 $\mu$g/kg , 훈연어류에는 N-nitrosothiazolidine이 13,700 $\mu$g/kg , 우리 나라 해산 식품 중 니트로소디메틸아민은 건조가오리, 동결건조명태, 건조오징어, 굴비 및 소건새우 등에서 2.8~86.0 $\mu$g/kg 으로서 비교적 높은 양이 검출되었을 뿐 아니라 이들 식품을 조리할 경우 3.6~13배 증가하였다. 또한 김치와 젓갈류 중에서도 니트로소디메틸아민이 검출된다는 연구가 있다. 식품 중 니트로소 화합물의 생성율 억제시키기 위하여 최근 20여년간 연구된 바를 요약하면 아스코르브산과 같은 억제제의 첨가, 가공방법 및 조리방법의 개선이 비교적 바람직한 방법으로 인정되고 있다. 위의 방법을 적용하여 베이컨을 조리한 결과 낮은 온도에서 오랜 시간 가열하는 것이 높은 온도에서 짧은 시간 가열한 것보다 니트로화 반응이 훨씬 낮았고 또 마이크로웨이브로 조리하는 것이 니트로소아민을 최소화 시키는 방법이었다. 염지육은 아스코르브산이나 토코페롤 등의 니트로화 억제제를 첨가할 경우 니트로소 화합물이 현저히 감소 하였는데 이는 산화질소의 소거 능력이 우수하기 때문인 것으로 밝혀졌다. 가공방법의 개선으로서는 가공시 식품을 공기에 노출시킬 경우 특히 직화로 가열된 공기에 노출되면 니트로소아민의 생성이 매우 높은 것으로 보고되어 있는데 그 대표적인 예로 맥아를 직화로 건조할 경우 맥주 중에 니트로소 화합물이 훨씬 높은 양이 검출된다고 보고되어 있다. 대체로 식품의 가공 조리 및 저장 중 니트로소화합물에 대한 메커니즘은 상세히 밝혀져 있으나 생체내에서의 생성이나 억제 등에 대한 연구는 아직도 미흡한 실정이라이 분야에 대한 연구가 절실히 요구된다.

• Journal of the Korea Concrete Institute
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• v.26 no.4
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• pp.517-524
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• 2014

Nitrite-Type hydrocalumite (calumite) is a material that can adsorb chloride ions ($Cl^-$) that cause corrosion of reinforce bars and liberate the nitrite ions ($NO_2{^-}$) that inhibit corrosion in reinforced concrete. In this study, polymer-modified mortars using two types of epoxy resin with calumite are prepared with various polymer binder-ratios of 0, 5, 10, 15, 20% and calumite contents of 0, 5%. The specimens are tested for chloride ion penetration, carbonation, drying shrinkage and corrosion inhibition. As a result, the chloride ion penetration and carbonation depth of PMM using epoxy resin somewhat increases with increasing calumite contents, but those remarkably decreases depending on the polymer-binder ratios. The 28-d drying shrinkage shows a tendency to decrease with increasing polymer-binder ratio and calumite content. Unmodified mortars with calumite content of 5% did not satisfy quality requirement by KS. However, it was satisfied with KS requirement by the modification of epoxy resin in cement mortar. On the whole, the carbonation and chloride ion penetration depth of epoxy-modified mortars with calumite is considerably improved with an increase in the polymer-binder ratio regardless of the calumite content, and is remarkably improved over unmodified mortar. And, the replacement of the portland cement with the calumite has a marked effect in the corrosion-inhibiting property of the epoxy-modified mortars.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.41-48
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• 2015

Juvenile banded catfish(Pseudobagurus fulvidraco, mean length $10.4{\pm}0.37cm$ and mean weight $14.5{\pm}0.46g$) were exposed to several nitrite(${NO_2}^-$) concentrations for 96h at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$. The result showed that cumulative mortalities of fish to ${NO_2}^-$ levels of 12.4, 19.8, 33.9 and 53.6 mg/L at pH levels of $6.18{\pm}0.54$ were 20, 25, 40 and 85%, respectively. At pH $6.5{\pm}0.54$, mortalities to ${NO_2}^-$ 22.4, 36.4, 45.3 and 63.2 mg/L were 25, 35, 50 and 100%, respectively. At pH $7.07{\pm}0.22$, mortalities to ${NO_2}^-$ 25.5, 45.7, 56.3 and 66.4 mg/L were 0, 55, 70 and 100%, respectively. The 96h-$LC_{50}$(median lethal concentration, $LC_{50}$) of fish to several ${NO_2}^-$ concentrations at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$ were assessed in these experiments. 96h-$LC_{50}$ at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$ were 32.68, 40.49 and 45.85 mg/L, respectively. It indicated that acute toxicity of ${NO_2}^-$ to juvenile banded catfish increased with low levels of pH and lengthening of exposure time to ${NO_2}^-$. In particular, smaller fish(mean weight $14.5{\pm}0.46g$) were more sensitive to ${NO_2}^-$ than larger fish(mean weight $81.7{\pm}1.42g$; not published). The 96h-$LC_{50}$ of juvenile banded catfish to ${NO_2}^-$ would be primary guideline for water quality management in the intensive culture system such as RAS and BFT.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.481-486
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• 2010

The nutraceutical role of omija (Schizandra chinensis Baillon) water extract (OWE) was determined through the analysis of antioxidant activity, nitrite scavening activity, and xanthine oxdiase and $\alpha$-glucosidase inhibitory effects. Antioxidant activity of OWE was measured by using 2,2-diphenyl-1-picryl-hydrazyl (DPPH) free radical scavenging activity and superoxide dismutase-like activity (SODA). DPPH radical scavenging activity and SODA increased in a dose-dependent manner, and was about 49.0% at 2.5 mg/mL and 69.2% at 5 mg/mL, respectively. The xanthine oxidase and $\alpha$-glucosidase inhibitory activities of OWE were about 88.8% and 86.2% at 1 mg/mL, respectively. Nitrite scavenging activity of OWE was about 54.9%, 42.4%, and 34.2% on pH 1.2, 3.0, and 6.0 at 1 mg/mL, respectively. These results suggest that OWE has a strong antioxidant activity, and xanthine oxidase and $\alpha$-glucosidase inhibitory effects.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.1-8
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• 2003

The purpose of this study was to investigate the effects of the sausage containing mulberry leaf(0.04%, 0.08%) and persimmon leaf powder(0.04%, 0.08%) on lipid oxidation(Thiobarbituric Acid Reactive Substances, TBARS), nitrite, volatile basic nitrogen(VBN) and fatty acid composition. The TBARS values of sausage containing mulberry leaf and persimmon leaf powder were not significantly different(p > 0.05) as compared to control during 45 days of storage, but TBARS values of sausage containing 0.04% mulberry leaf and persimmon leaf powder were significantly lower than those of control at 60 days of storage. The nitrite scavenging ability of sausage containing mulberry leaf and persimmon leaf powder was higher than that of control. The VBN content of all treatments significantly increased(p < 0.05) during the storage periods. In fatty acid compositions, the percentages of PUFA/SFA of sausage containing mulberry leaf and persimmon leaf powder were significantly higher as compared to control. In conclusion, sausage containing mulberry leaf and persimmon leaf powder was a more effective natural resource on the basis of the lipid oxidation and nitrite scavenging ability of sausage.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.129-135
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• 2019

Juvenile Paralichthys olivaceus (mean weight 685.3±36.7 g) were raised in different and closed recirculating bio-floc system (control, bio-ball, and shelter) for 7 months. The water environment such as water temperature, dissolved oxygen, salinity, pH, and alkalinity according to the difference of closed recirculating system remained stable during the rearing period. No significant changes were observed in dissolved inorganic nitrogen such as ammonia, nitrite, and nitrate were observed in different closed recirculation system. The final weights according to the difference of closed recirculating were 1,524 g (control), 1,674 g (bio-ball), and 1,630 g (shelter). The survival rate was higher than 98%, and the final FCRs (Feed coefficient ratio) were 1.2, 1.1, and 1.2. The results of this study indicated high growth and survival rate in all systems.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.741-747
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• 2011

Gardenia fructus has been reported to have bioactivities of lowering blood glucose, antitumor, antithrombosis, repression of neogenesis of blood vessels, antioxidant and antibiosis. However, the nitrite scavenging activity and utilization in meat products have not been studied. The substitution effect for nitrite and antibiosis of Gardenia fructus extract (GFE) were investigated by measuring the residual nitrite contents and storage properties of pork patties prepared with nitrite (50, 100, and 150 ppm) and GFE (0, 0.25, 0.5%). The CIE $L^*$ and CIE $a^*$ of pork patties decreased, while CIE $b^*$ increased as the addition of GFE increased. Patties with more GFE added tended to be lower in pH when stored at $4^{\circ}C$ for 6 wk, but TBARS and VBN were not affected by the addition of GFE. Residual nitrite in patties was lowered as the storage period was lengthened and as the GFE addition was increased. During the storage at $4^{\circ}C$, Escherichia coli was not detected, and the total aerobic bacterial count was decreased as more GFE was added, showing the substitution effect of GFE for nitrite in antimicrobial activity. In conclusion, the results show that GFE has nitrite scavenging and antibiotic activities in meat products, suggesting its potential use in healthy and sustainable foods with diverse biofunctionalities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.512-519
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• 2013

The antioxidant activities of ethanolic extracts obtained from medicinal plants (Scutellaria baicalensis Georgi, Acanthopanax sessiliflorum Seeman, Pueraria lobata Ohwi, Portulaca oleracea Linne, Crataegus pinnatifida Bunge var. typica Schneider, Euonymus alatus Apterus, Hovenia dulcis Thunberg, Prunus yedoensis Matsumura, Albizzia julibrissin Durazz., Chrysanthemum indicum Linne) were evaluated for total phenolic content, total flavonoid content, DPPH radicals, nitrites, $Superoxide^-$ radicals, $ABTS^+$ radical scavenging activity, and reducing power. Antioxidant capacities were the highest in Prunus yedoensis Matsumura for DPPH radical scavenging activity ($IC_{50}$ $5.39{\mu}g/mL$), reducing power (2.72, $A_{700}$), and nitrite scavenging activity ($IC_{50}$ $167.94{\mu}g/mL$). Hovenia dulcis Thunberg and Acanthopanax sessiliflorum Seeman were effective for their nitrite scavenging activities (over 90% at 1 mg/mL). The $Superoxide^-$ radical scavenging activity of Prunus yedoensis Matsumura ($IC_{50}$ $43.39{\mu}g/mL$) was stronger than tannic acid ($IC_{50}$ $46.51{\mu}g/mL$). Five samples (Prunus yedoensis Matsumura, Acanthopanax sessiliflorum Seeman, Hovenia dulcis Thunberg, Crataegus pinnatifida Bunge var. typica Schneider, Scutellaria baicalensis Georgi) were effective for their $ABTS^+$ radical scavenging activity (more than 90% at 0.5 mg/mL). These results suggest that the ethanolic extracts of Prunus yedoensis Matsumura could be used as a functional ingredient in food products.