Zeolitic imidazolate frameworks (ZIFs) along with carbon nanofibers and polyaniline composite have been explored as an electrochemical sensing platform in nitrite measurement at trace level. Owing to their topology, high surface area and porous structure, these metal–organic frameworks (MOFs) find widespread utility in different application domains. Nitrites are widely used as preservatives in dairy, meat products, and packaged food stuffs. They form N-nitrosamines, which are potential carcinogens and cause detrimental health effects. These ZIF-based MOFs along with carbon nanofibers and polyaniline have emerged as an efficient electrochemical sensing material. The composite has been characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and BET surface area studies. The electrochemical performance of the composite has been evaluated by forming as a thin film of composite on the surface of glassy carbon electrode and studying its impedance as well as electrochemical sensing behavior. The sensor exhibited good analytical response in nitrite measurement with a limit of detection of 8.1 μM. The developed sensing platform has been successfully applied to quantify the nitrite levels from water samples. The results obtained are in good agreement with the results of standard protocol.

In the present study, an innovative electrochemical sensing platform was established for sensitive detection of NO2 —. This sensor was developed using CoFe alloy encapsulated in nitrogen-doped carbon nanocubes (named as CoFe@NC-NCS), synthesized through the calcination of polydopamine-coated CoFe Prussian-blue analogues (CoFe-PBA@PDA). The morphological and electrochemical characterization reveals that the CoFe@NC-NCS possesses high electrocatalytic activity for electrochemical quantitation of NO2 —, ascribed to the huge surface area and plentiful active positions, benefiting from the porous, hollow, and core–shell structure of CoFe@NC-NCS. Under the optimal conditions, CoFe@NC-NCS/GCE possessed remarkable sensing performance for NO2 — with wide liner ranges and a detection limit of 0.015 μM. NO2 — recovery experiments in real samples exhibited recoveries in the range of 98.8–103.5%. Hence, the CoFe@NC-NCS shows great promise for the construction of electrochemical sensor with more potential application.

This work describes the facile synthesis of silver nanoparticle-decorated zinc oxide nanocomposite through a simple glycol reduction method. The silver nanoparticle-decorated zinc oxide nanocomposite-based pencil graphite electrode has been validated as a perceptive electrochemical sensing podium towards nitrite. The morphology of the prepared nanocomposite has been characterized via specific spectroscopic and electrochemical techniques. The sensor exhibits a notable enhancement in the cyclic voltammetric response to nitrite oxidation at an ideal peak potential of 0.76 V in pH 6.0 acetate buffer. Under optimum conditions of nitrite directly expanded with their concentration in the range from 30 to 1400 μM with a detection limit of 14 μM.

This study investigated various levels of sodium nitrite and probiotics (SNPro) combination as an alternative to zinc oxide on the growth performance, immune response, intestinal microflora, and morphology of weaned pigs. One hundred and ninety-two weaned pigs (Landrace×Yorkshire×Duroc) with an average body weight of 6.51±0.15 kg were randomly assigned to four treatments(n=6) on the basis of their initial body weight. Experimental period was divided into phase 1 and 2 (each 14 days). The dietary treatments were: 1) Basal diet (control), 2) SNPro1 (control+0.01% SNPro), 3) SNPro2 (control+0.02% SNPro), 4) SNPro3 (control+0.03% SNPro). The average daily gain when SNPro was added to the diet was 288, 309, 319, 324 g in phase 1, 355, 387, 410, 407 g in phase 2 and 321, 348, 364, 366 g in the overall. The concentration of interleukin-8 and interleukin-10 in serum when SNPro was added to the diet were 15, 13.5, 13, 12.8 ng/ml and 165, 162, 155, 145 ng/ml (p<0.05) but toll-like receptor 4 and immunoglobulin G levels in serum were no significantly different. The colonization of Escherichia coli in the ileum and Salmonella spp. in the caecum were significantly decreased as SNPro level increased (p<0.05). However, the population of Lactobacillus spp. did not differ among the groups. Although villus height and villus height to crypt depth ratio were not significantly affected by the treatments, crypt depth in the jejunum was 599, 586, 615, 599 ㎛ as SNPro level increased (p<0.05). In conclusion, SNPro had beneficial effects on growth performance, immune response, intestinal microflora and morphology weaned pigs. Therefore, SNPro not only can be considered as an alternative for the pharmacological level of zinc oxide in weaning pigs but also ideal dietary SNPro level was 0.02%.

본 실험에서 아질산 급성노출은 대왕범바리의 혈액학적 성상 및 혈장성분에 유의적 변화를 나타내었다. 혈액학적 성상인 Hct와 Hb는 아질산 노출에 의한 유의적 감소를 확인하였다. 혈장 성분인 glucose, cholesterol, GPT 및 ALP는 아질산 노출에 의해 유의적으로 변화를 나타냄을 확인 하였다. 본 실험의 결과 아질산 노출 100 mg L-1 이상의 농도는 대왕범바리의 혈액 성상 및 혈장 성분의 유의적 영향을 미치며, 800 mg L-1의 아질산 급성 노출은 대량 폐사를 유발할 수 있으나, 기존 국내 양식 대상종인 Olive flounder, P. Olivaceus는 171.043 mg L-1 (Kim et al. 2018), Yellow tail, Seriola quinqueradiata는 147 mg L-1 (Sugiyama et al. 1991)에 비해 상대적으로 높은 값을 보여 아질산 내성이 상대적으로 강함을 확인할 수 있었다.

This study investigated the antioxidant properties of the Radix isatidis extract and the effect of substituting it with sodium nitrite (SN) in a pork patty. The antioxidant activity of the Radix isatidis water extract (RIWE) was compared to those of the methanol and chloroform extracts (RIME and RICE, respectively). Patties were prepared with five different treatments: (1) a control with no RIWE and SN, (2) T1 with 150 ppm SN, (3) T2 with 100 ppm SN + 0.1% RIWE, (4) T3 with 50 ppm SN + 0.3% RIWE, and (5) T4 with 0.5% RIWE. They were used to compare the oxidation stability for 12 days at 4℃. The extraction yield of RIWE was 3.2 and 18.7 times higher (p<0.05) than those of RIME and RICE, respectively, but RIWE had the lowest (p<0.05) 1,1`-diphenyl-2-picrylhydrazyl radical scavenging activity, superoxide dismutase-like activity, and total reducing ability. Patties with RIWE and SN exhibited lower (p<0.05) pH values after 12 days, compared to the control. After 4 days, the 2-thiobarbituric acid reactive substances content was lower (p<0.05) in T1, T2, T3, and T4 than in the control. The oxidation-reduction potential value was the lowest (p<0.05) in T3 and T4 after 4 days (p<0.05). T1, T2, T3, and T4 had a lower (p<0.05) volatile basic nitrogen content after 12 days, compared to the control. These findings suggest that RIWE has an antioxidant effect similar to that of SN, but further research on its antimicrobial effect may be required to determine if it is a good substitute for SN.

To investigate effects of starvation on physiological changes, stress response, and survival of cobitid loach (Misgurnus anguillicaudatus) exposed to sodium nitrite (NaNO2), a 4- week experiment was conducted. Fewer fish survived in the starved group than those in the fed group during the experiment. Starvation resulted in growth retardation, leading to differences in body length and body depth between fed and starved groups. The fed gorup continued to grow and remained in good condition. Blood chemical analysis (plasma cortisol and glucose) showed significant differences in stress response to nitrite exposure between fed and starved groups (p < 0.05). These results suggest that all parameters employed in this study to assess effects of starvation with NaNO2 stress are useful information for researching nutritional status in cobitid loach.

본 연구는 아질산나트륨 및 비타민 C의 대체로 첨가한 수벌번데기 분말이 유화형 소시지의 이화학적 품질 특성에 미치는 영향을 구명하고자 하였다. 시료는 아질산염, 비타민 C 및 수벌번데기 분말의 첨가 수준에 따라 각각 아질산나트륨 150 ppm+비타민 C 200 ppm(대조구), 아질산나트륨 75 ppm+ 비타민C 100 ppm+수벌번데기 분말 6.015%(T1) 또는 수벌번데기 분말 12.03%(T2)을 첨가하여 제조한 후 4℃에 30일 동안 저장하였다. pH는 수벌번데기 분말의 첨가 수준이 증가함에 따라 현저하게 감소하였다(p<0.05). 일반성분 함량은 수벌번데기 분말의 첨가 수준이 높은 소시지에서 낮은 수분 및 조단백질 함량과 높은 조지방 및 조회분 함량을 보였다 (p<0.05). 지방산 조성은 T1과 T2가 대조구에 비해 포화지방산 함량이 높았으나(p<0.05), 불포화지방산 및 다가불포화지 방산 함량은 낮았다(p<0.05). 색깔은 T1과 T2가 대조구보다 현저하게 낮은 명도(L*) 및 적색도(a*)와 높은 황색도(b*) 및 hue-angle(h°)을 보였으며(p<0.05), T2의 경우 가장 낮은 chroma(C*)를 나타내었다(p<0.05). 지방산화물(TBARS) 함량은 T2가 가장 높았으며(p<0.05), 특히, 대조구보다 2배 이상 높았다. 조직감은 T1과 T2가 저장기간 동안 대조구에 비해 단단한 특성을 보였다(p<0.05). 따라서 유화형 소시지에서 수벌번데기 분말의 첨가는 색깔, 지방산화안정성 및 조직감에 부정적인 영향을 미치는 것으로 나타나, 아질산나트륨 및 비타민 C 대체 효과가 없었다

Nitrite and nitrates are usually used in the production of meat products as food additives even though they pose a secondary risk. In this study, the residues of nitrite and nitrate ions in 366 processed meat products distributed in Seoul were analyzed using ion chromatographs and UV spectrophotometers. In all tested products, the residues of nitrite were below 70 mg/kg, which met the processing standard and component specification for livestock products. Evaluation of nitrite ions, revealed a mean concentration of 7.1 - 11.9 mg/kg in hams, sausages, and bacons, while higher ratios of nitrite were found in other types of products. Among the studied processed meat products, at least 60% of hams and sausages had indications of nitrite, as did 90% of bacons and dry meats. No spiced meat and less than 10% of crushed meat had indications of nitrite. However, all dried meats showed below 1 mg/kg, regardless of whether they had indications of nitrite. Up to 9.7 mg/kg of nitrite was detected in the products with no indication of nitrite, and 14.6% of all products had at least 1 mg/kg of nitrite. This can be attributed to the reduction of residual nitrate ions in the products into nitrite ions. A review of the concentrations of nitrate ions in processed meat products by type suggests that the mean concentration was 22.3 (maximum 110.2) mg/kg in hams, 31.8 (maximum 89.5) mg/kg in sausages, 16.4 (maximum 28.2) mg/kg in bacons, 16.8 (maximum 61.1) mg/kg in spiced meats, 20.2 (maximum 99.4) mg/kg in crushed meats, and 121.0 (maximum 216.5) mg/kg in dried meats. Therefore, dried meats showed much higher nitrate ion concentrations than other types of meat products; however, the residue of nitrite ions in actual dried meats was found to be lower than 1 mg/kg, suggesting that the concentrations of nitrate ions do not affect those of nitrite ions. However, a certain concentration of nitrate ions was observed even when nitrate ions were not used in the products, as nitrite ions were transformed into nitrate ions and nitrite ions were detected even the products with no indication of nitrite ions. Therefore, continuous monitoring and preparation of relevant standards of the use of nitrate in processed meat products are necessary.

This study was performed to evaluate physicochemical properties of model sausages with various levels of pressed cherry fruit extracts alone or in combination with tomato powders as a partial replacement of sodium nitrite. In study 1, physicochemical properties of model sausages were not affected by the addition of pressed cherry fruit extracts(p>0.05), except for Hunter L(lightness) and Hunter a(redness). Model sausages containing pressed cherry fruit extract(T1, 0.5% and T2, 1.0%) decreased lightness, whereas redness of REF(156 ppm sodium nitrite) was not different from T2(p>0.05). However, those with cherry fruit extract at 1% were proper to improve the hunter color values, especially redness values. In study 2, physicochemical properties of model sausages were not affected by the addition of pressed cherry fruit extract and tomato powders in selected nitrite contents, except for color and cooking loss(p>0.05). In color values, REF was the highest level, and T2, T4, and T5 was significantly low level in lightness (Hunter L). T2 was the highest value in cooking loss(%) among other treatments. The redness values(Hunter a) of T5(75ppm, nitrite, 1% pressed cherry fruit extract and 0.5% tomato powder) were not different from REF which had highest redness values(P<0.05). In conclusion, the combination of pressed cherry fruit and tomato powder might be considered as an alternative method to partially replace with sodium nitrite in pork model sausages.

영지버섯과 기타 약용버섯류를 에탄올 용매로 추출하여 농축한 뒤, 100 μg/ml의 농도로 처리하여 아질산염 소거 능을 실험한 결과 양성대조구인 Ascorbic acid는 25%의 소거능을 보이는데 반해 영지버섯 중 ASI 7080은 40%이 상 소거하는 것으로 나타났으며, 그 다음으로는 상황버섯 이 37%를 보였다. ASI 7002도 양성대조구보다 높게 나 타났.고, 그 이외의 다른 실험구는 양성대조구인 Ascorbic acid보다 낮은 아질산염 소거능을 보였다. NO assay 실험을 한 결과, 양성대조구로 쓰인 Ascorbic acid는 항염증 효능이 55%인데 반해 ASI 7002는 78.5% 로 가장 높은 항염증 효능을 보였으며, 그 다음으로 ASI 7063이 67.5%를 보였다. 기타 약용버섯류인 동충하초는 71.2%로 가장 높게 나타났으며, 노루궁뎅이 버섯은 59.7%의 소거능을 보였다. 영지버섯 ASI 7002를 에탄올 용매로 추출하여 농축한 뒤, 농도별(10, 50, 100 μg/ml)로 처리하고 LPS 10 μg/ml 처리한 RAW 264.7 cell 에서 RNA를 추출하여 cDNA를 합성한 후 Real-time PCR kit 를 이용하여 염증 관련 유전자인 iNOS와 COX-2와 TNF-a의 primer를 Table 1과 같이 제작하였고, iNOS와 COX-2와 TNF-a의 발현정도를 본 결과 세 유전자 모두 농도 의존적으로 발현이 억제되는 것을 확인할 수 있었다.

본 연구에서는 축산물 및 축산가공품에서 천연적으로 유래되는 질산염과 아질산염의 함유량을 조사하였다. 식육223건, 식육가공품 51건, 원유 30건, 유가공품 142건, 알류 5건 및 알가공품 7건으로 총 458건에 대해 이온크로 마토그래피(IC)를 이용하여 질산염과 아질산염을 분석하였다. 이 때, 축산물 가공기준 및 성분규격의 전처리법과 기기조건을 이용하여 분석하였으며 축산물 및 축산가공품에 적용하여 시험법 검증(직선성, 검출한계, 정량한계, 회수율, 재현성 및 측정불확도)을 실시한 결과, 모두 양호한값으로 나타났다. 총 458건을 분석한 결과, 질산염이 167건에서 아질산염이 40건에서 검출되어 질산염이 아질산염에 비해 검출된 건수가 많았다. 질산염의 경우, 조제분유류에서 ND~40.23 mg/kg으로, 양념육류에서 ND~37.97 mg/kg으로, 가공치즈류에서 ND~32.40 mg/kg으로, 알가공품에서 4.92~31.50 mg/kg으로, 분유류에서 ND~27.73 mg/kg으로, 소시지류에서 ND~22.45 mg/kg으로, 베이컨류에서 ND~22.45 mg/kg으로, 자연치즈류에서 ND~21.55 mg/kg으로, 햄류와 발효유류에서 ND~20.82 mg/kg으로, 알류에서 ND~13.57 mg/kg으로, 버터류에서 ND~12.77 mg/kg으로, 우유류에서 ND~9.31 mg/kg으로, 식육류에서 ND~3.88 mg/kg의 순으로 나타났다. 한편, 아질산염은 알가공품에서 1.84~17.35 mg/kg으로 나타났으며 식육류에서는 ND~1.92 mg/kg의 범위로 검출되었다.

This study was to conducted to investigate the antioxidative activity of 70% ethanol extracts of kiwi of three different colors (gold, green and red) by measuring DPPH, ABTS radical scavenging activity, tyrosinase inhibitory effect, metal chelating effect, reducing power, and nitrite scavenging activity. Total polyphenol contents were: gold kiwi, 3.09 mg GAE/g, green kiwi 2.71 mg GAE/g, and red kiwi 4.59 mg GAE/g, respectively. Red kiwi showed higher antioxdidant activity than gold and green kiwi. DPPH and ABTS radical scavenging activity, and nitrite scavenging activity of red kiwi exhibited 94.83, 99.57, and 97.88%, respectively, at a concentration of 20 mg/mL, which were equal to those of ascorbic acid (positive control). Metal chelating effect of red kiwi was superior to that of ascorbic acid. Therefore, the availability of red kiwi will be increased in the field of functional material for food additives and value added products.

This study was conducted to examine the antioxidative effect and nitrite scavenging ability of extract from Acanthopanax cortex shoot. The total phenolic compound and flavonoids contents of extract from Acanthopanax corex shoot were 116.33±6.09 ㎎ GAE/g and 65.07±4.10 ㎎ RE/g, respectively. Antioxidative activities were measured by various in vitro models such as DPPH radical scavenging activity, FRAP, reducing power, ABTS radical scavenging activity, ORAC assay. This results showed that the extract of Acanthopanax cortex shoot was effective in scavenging radicals and protecting oxidation when assessed various in vitro systems. Similarly, the nitrite scavenging ability of extract was increased in a dose dependent manner. Moreover, ORAC value at a concentration of 0.1 ㎎/㎖ was 103.4±5.6μM TE/g. Considering high consumer demand beneficial health effects, Acanthopanax cortex shoot can be utilized to develop functional food health-promoting and natural antioxidant agents.