In the current study, 109 commercial nut samples were collected from different Korean markets and analyzed for the contamination of 5 different mycotoxins (aflatoxin, ochratoxin A, deoxynivalenol, zearalenone, and T-2 toxin) using ELISA kits. The results revealed that the most frequently detected mycotoxin was zearalenone (n=36, 33%), followed by aflatoxin (n=31, 28.4%) and ochratoxin A (n=30, 27.5%). Deoxynivalenol and T-2 toxin were also detected in 22 (20.3%) samples, respectively. Among 109 nut samples, 33 samples (30.3%) were contaminated only with one kind of mycotoxin, whereas 43 samples had at least 2 kinds of mycotoxins. Two samples were contaminated with as many as 4 different mycotoxins, and they were both walnuts. Although the monitoring results revealed the amount of aflatoxin contamination was under the safety criteria, there is no current safety guideline for other kinds of mycotoxins or multiple contaminations in Korea. Therefore, further studies should be performed to reveal the distribution of mycotoxin in different foods and propose appropriate safety guidelines for Korean markets.

Ochratoxin A (OTA) is one of the most important mycotoxins owing to its widespread occurrence and toxicity including nephrotoxicity and potential carcinogenicity to humans. Since OTA is stable under most food processing conditions, OTA has been detected not only in a wide range of agricultural commodities such as cereal grains but also their processed products. Nonetheless, it is known that significant reduction of OTA may be achieved under higher temperature and alkaline conditions. In this study, the effects of retorting cooking process on the stability of OTA in spiked (20 μg/kg of dry weight basis) rice and oat porridge (10% solid content; w/v) in the presence and absence of baking soda was investigated using a laboratory horizontal steam retort system. The samples were heated in a pot at 85°C central temperature until it becomes gelatinized, packed in retort pouched, and heat-processed in pressurized retort machine (at 121°C for 25 min) followed by drying in 50°C oven overnight. Samples were analyzed for OTA by high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The reduction of OTA in retorted rice and oat porridge were 54% and 17%, respectively, while greater reduction of OTA was observed at increased amount of baking soda. The reduction of OTA in retorted rice porridge with 0.5% and 1% baking soda were 55% and 66%, respectively. In the retorted oat porridge, reduction of OTA was also evident to result in 30% and 48% with 0.5% and 1.0% of added baking soda, respectively. These results suggest that OTA in rice and oat may be reduced significantly by retorting process. In addition, added baking soda may positively impact the reduction of OTA.

Ochratoxin A, which is frequently detected in cereals and infant diets worldwidely, is a mycotoxin to damage mainly the kidney and liver. Because ochratoxin A is highly thermostable compound. it is necessary to study ways of reducing level of ochratoxin A by controling processing steps. However, food processes, including extrusion, expansion, roasting, and steam cooking, which are used in order to mitigate the contents of ochratoxin A, are known to produce polycyclic aromatic hydrocarbons, which are generated from radicals decomposed by pyrolysis. Therefore, this study analyzed the levels of 4 polycyclic aromatic hydrocarbons, benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based products made in high pressure and heating process. Rice samples were finely ground, and homogenized samples were alkaline treatement with 1 M KOH/EtOH and extracted with liquid-liquid extraction method using n-hexane. The extracted solution was pretreated with a silica cartridge. The purified solution was dried with nitrogen gas and dissolved in 1 mL of dichloromethane and injected into GC/MSD. We had overall recoveries for 4 polycyclic aromatic hydrocarbons spiked into rice samples ranging from 92.8 to 110.2%. The limit of quantitations of benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based product were 0.19 ng/g, 0.38 ng/g, 0.51 ng/g, and 0.31 ng/g, respectively. However, these 4 polycyclic aromatic hydrocarbons in all processed rice samples were not detected.

Ochratoxin A (OTA) is one of the most important mycotoxins due to its prominent nephrotoxicity as well as potential carcinogenicity to human. OTA has been detected in a wide range of agricultural commodities including cereal grains and their processed products. OTA is stable under most food processing conditions while the reduction of OTA is more rapid and extensive under higher temperature and alkaline conditions. In this study, the effects of extrusion cooking on the stability of OTA in spiked (100 μg/kg) rice flour (moisture content, 16% wet weight basis) in the presence and absence of baking soda was investigated using a laboratory scale twin-screw extruder. The extrusion variables were temperature (120 and 150°C), screw speed (150, 200, and 250 rpm), and baking soda (0, 0.5, and 1%, w/w). Both unextruded and extruded samples were analyzed for OTA by high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The reduction of OTA was in the range of 78-82% with no added baking soda, whereas lesser reductions of 75-80% and 72-77% were observed at 0.5% and 1% baking soda, respectively. Both temperature and screw speed did not affect reduction of OTA during extrusion regardless of the presence or absence of baking soda. While the total color difference (ΔE) of extruded samples were increased with baking soda content, the radial expansion of extruded samples were decreased with baking soda content. These results suggest that OTA in rice flour may be reduced significantly by extrusion. In addition, added baking soda may negatively impact the reduction of OTA while its mechanism of action is unknown.

The objective of this study was to optimize analytical methods for ochratoxin A (OTA) and zearalenone (ZEA) in rice straw silage and winter forage crops using ultra-high performance liquid chromatography (UHPLC). Samples free of mycotoxins were spiked with 50 μg/kg, 250 μg/kg, or 500 μg/kg of OTA and 300 μg/kg, 1500 μg/kg, or 3000 μg/kg of ZEA. OTA and ZEA were extracted by acetonitrile and cleaned-up using an immunoaffinity column. They were then subjected to analysis with UHPLC equipped with a fluorescence detector. The correlation coefficients of calibration curves showed high linearity (R2 ≧ 0.9999 for OTA and R2≧0.9995 for ZEA). The limit of detection and quantification were 0.1 μg/kg and 0.3 μg/kg, respectively, for OTA and 5 μg/kg and 16.7 μg/kg, respectively, for ZEA. The recovery and relative standard deviation (RSD) of OTA were as follows: rice straw = 84.23~95.33%, 2.59~4.77%; Italian ryegrass = 79.02~95%, 0.86~5.83%; barley = 74.93~97%, 0.85~9.19%; rye = 77.99~ 96.67%, 0.33~6.26%. The recovery and RSD of ZEA were: rice straw = 109.6~114.22%, 0.67~7.15%; Italian ryegrass = 98.01~109.44%, 1.65~4.81%; barley = 98~113.53%, 0.25~5.85%; rye = 90.44~108.56%, 2.5~4.66%. They both satisfied the standards of European Commission criteria (EC 401-2006) for quantitative analysis. These results showed that the optimized methods could be used for mycotoxin analysis of forages.

돼지고기 중 5종의 곰팡이독소(아플라톡신 B1, B2, G1, G2 및 오크라톡신 A)를 분석하기 위해 0.1% 개미산을 함유한 50% 아세토니트릴용액으로 추출한 후 고체상추출칼럼을 이용하여 정제하고, LC-MS/MS로 동시 정량할 수 있는 시험법을 마련하였다. 분석조건으로 측정한 5종의 곰팡이독소 matrix-matched 표준곡선식에서 모두 상관계수 0.998이상의 상관관계를 나타내었다. 5종의 곰팡이독소 2배의 정량한계에서 10배의 정량한계로 첨가한 시료에서 평균 회수율은 72.1~109.9%로 실험 결과들이 EU 가이드라인에서 제시하는 유효성 확인을 위한 기준을 만족함으로써 시험법의 신뢰성을 확보할 수 있었다. 충청지역 유통되고 있은 돼지고기 20건에 대한 총아플라톡신 및 오크라톡신A에 대한 오염도 조사결과 정량한계 미만으로 조사되었다.

Ochratoxin A와 aflatoxin은 곰팡이 독소 생산 균주가 자연 발효되는 식품에 오염되거나 발표식품의 종균을 분별없이 선택했을 때 검출 될 수 있다. 본 연구에서는 다양한 배양 환경이 ochratoxin A와 aflatoxin의 생산에 주는 영향에 대해 연구하였다. Aspergillus usamii KFRI 999와 A. awamori KFRI 983의 배양 온도, 배양 배지, 배양 시간을 달리하여 ochratoxin A생산 정도를 분석하였다. 또한 초기 pH, 온도, 배양 시간, 배양 배지를 다르게 하였을 때 A. flavus KACC 41403와 A. oryzae KACC 46471가 생산하는 aflatoxin의 양을 평가하였다. Ochratoxin A와 aflatoxin의 양은 HPLC로 분석하였다. 연구 결과, 곰팡이 독소는 배양 온도에 큰 영향을 받는 것으로 나타났다. A. oryzae KACC 46471는 aflatoxin을 생산하지 않았다. 곰팡이 독소를 생산하는 균주는 모두 30℃에서 가장 높은 독소 생산량을 보였다. A. awamori KFRI 983은 PDA 배지에서 가장 적은 ochratoxin A 생산량을 보였다. 본 연구 결과는 다양한 식품의 ochratoxin A와 aflatoxin 저감화에 유용하게 활용 될 수 있다.

Mycotoxins such as aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEA) are widespread contaminants of food and feedstuffs. It is very likely, that humans and animals are always exposed to mixtures of mycotoxins rather than to individual compounds. Therefore, risk assessments should consider mixture toxicity data. In the present study the combination of AFB1, OTA and ZEA was tested for genotoxicity in rat bone marrow and blood leukocytes after 15, 30 and 60 days treatment. The level of DNA damage was determined by the comet assay. The tail intensity and Olive tail moment in leukocytes and bone marrow cells were significantly higher than in controls. At the same time, the level of DNA damage in bone marrow cells was higher than in leukocytes. The data suggests that prolonged exposure to mycotoxins combination through food consumption can induce DNA damage contributing to the harmful effects in vivo.

2012년 2월부터 11월까지 인천 지역에서 유통된 건고추 및 고춧가루 193건을 대상으로 아플라톡신 B1과 오크라톡 신 A의 오염도를 조사하였다. Immunoaffinity column 및 HPLC를 이용한 시험법은 모두 80% 이상의 회수율을 보였고, 아플라톡신 B1 및 오크라톡신 A의 검출한계는 각각 0.13 μg/kg, 0.30 μg/kg였다. 오염도 조사를 한 결과 아플라 톡신 B1은 17.1%의 검출율을 보였고 오크라톡신 A는 20.7% 의 검출율을 보였으며, 아플라톡신 B1의 검출농도는 0.14~ 9.67 μg/kg였고, 오크라톡신 A의 검출 농도는 0.31~3.31 μg/ kg였다. 이는 우리나라 식품공전 상의 기준인 10 μg/kg(아 플라톡신 B1), 7 μg/kg(오크라톡신 A)보다는 낮은 수치로 비교적 안전한 수준이었다.

아플라톡신 및 오크라톡신 A의 동시분석법을 확립하여보다 신속하고 경제적인 분석을 통해 아플라톡신과 오크라톡신 A를 효율적으로 관리하고자 하였다. 시료의 전처리는 80% methanol로 추출하고 면역친화성 컬럼을 이용하여 정제한 다음 trifluoroacetic acid를 이용하여 유도체화 한 후 HPLC-FLD로 분석하였다. 컬럼은 Capcell pak-C18(4.6 mm × 150 mm, 5 μm)을 사용하였으며, 이동상은water : acetonitrile : methanol (72 : 14 : 14) 용액과 acetonitrile: 0.1% phosphoric acid (50 : 50) 용액을 구배용매조성(gradient mode)으로 분석하였다. 형광검출기의 파장은 파장프로그램을 사용하여, 여기파장 360 nm, 검출파장 450 nm과 여기파장 330 nm, 검출파장 460 nm으로 분석하였다. 아플라톡신 B1, B2, G1, G2와 오크라톡신 A의 직선성을 검토한 결과 상관계수(R2) 0.9997~0.9998의 범위였고, 검출한계와 정량한계는 각각 0.05~0.18, 0.16~0.60 μg/kg이었다. 회수율은 아플라톡신 B1, G1, B2, G2, 오크라톡신 A 각각78.4~101.5%, 73.3~102.1%, 81.7~106.7%, 67.0~104.6%,78.7~120.8%이었다. 확립된 동시분석법을 통한 국내 유통식품을 대상으로 모니터링을 실시한 결과 총 151건 중 13건에서 아플라톡신및 오크라톡신 A가 검출되었으며 검출 범위는 아플라톡신B1은 0.32~1.80 μg/kg, 오크라톡신 A는 0.97 μg/kg이었다. 이들 결과로부터 우리나라에서 유통 중인 조사한 식품 151건의 아플라톡신과 오크라톡신 A의 검출량은 모두 기준치 이하로 적합한 것으로 조사되었으며 안전한 수준임을알 수 있었다.

Aflatoxin (AF) and Ochratoxin A (OTA) are carcinogenic and possible carcinogenic mycotoxins respectively produced by Aspergillus spp or Penicillium spp. The study for contamination survey and proposal for reduction of mycotoxin in red pepper were carried out. 192 samples were collected at such various stages and markets as pre/post-harvest stages, internet shopping mall /super-market and small stakeholder mill/geographically indicated company. As only 2 samples were positive for aflatoxin, so contamination rate was 1.04%. In the meanwhile, contamination rate for ochratoxin A was 21.88% and a various amount of OTA was detected in 42 positive samples. 6 samples were found to be contaminated at higher level than 5 μgkg−1 for ochratoxin A, which was established recently as a maximum permissible limit in korea. There was no difference in degree of contamination with regard to cultivation type because any mycotoxin was not found at all in both organically and conventionally grown red pepper. But, there was statistically significant difference in the process of manufacturing. Finished products were OTA-contaminated at a level of 2.32 ± 6.54 μgkg−1(mean ± SD), even though OTA was not detected in deep frozen red peppers right after long term storage. And contamination for OTA was a level of 0.33 ± 0.91 μgkg−1(mean ± SD) in red paprika powder after uv sterilization, while the contamination for OTA was 2.78 ± 4.49 μgkg−1(mean ± SD) in non-uv sterilized powder. In addition, our investigation shows that higher OTA contamination occurred in some of famous brand products sold in super-market and domestic products than products collected through on-line shopping or from small stakeholder mills and imported products respectively, however, difference was not statistically significant.

Induction of DNA fragmentation of rat embryonic midbrain cells was studied to see whether apoptosis plays a role in OTA-induced microcephaly observed in cultured rat whole embryos during embryogenesis. We first cultured whole embryos (prepared from day 9.5 gestation rats) for 48 hrs with OTA and found that OTA induced microcephaly in cultured rat whole embryos. We also examined whether the microcephaly seen in cultured whole embryos is partially related to the increase of apoptosis of undifferentiated embryonic midbrain cells. Embryonic midbrain cells were prepared from day 12 gestation rat embryos, and cultured in the mixture media of Dulbecco's modified eagle's medium nutrient and Ham's F12 (1 : 1) containing 10% Nuserum, 100 ㎍/㎖ of streptomycin and 100 units/ml of penicillin for 96 hrs. Induction of DNA fragmentation was increased by 0.25-1 ㎍/㎖ OTA in a dose dependent manner in the embryonic midbrain cells. We also tested whether increase of apoptosis by OTA would be associated with change of apoptosis-related proteins (TNF-α and P^(53)) level in embryonic rnidbrain cells. OTA also increased TNF-α and P^(53) levels. These results show that OTA induced microcephaly in cultured whole embryos and this effect may be at least a part due to the induction of apoptosis and apoptosis-related protein levels of undifferentiated embryonic midbrain cells.

곰팡이 독소인 ochratoxin A(OA)는 신장독성, 최기형성, 발암성 및 면역독성을 나타내며, 식품, 곡류 및 정육 등에 잔류한다고 알려져 있다. 최근 우리나라의 된장, 간장등 발효식품에서도 OA가 검출되었다는 보고가 있어 OA에 대한 관심이 높아지고 있다. 본 연구에서는 OA의 전반적인 위해성 평가의 일환으로 OA의 독성 표적장기인 신장에 초점을 맞추어 신장독성 감소방법을 제시하고자 한다. 신장독성을 감소시키기 위한 대상물질로는 1) 기존에 독성감소 물질로 알려진 phenylalanine(Phe), 2) phenylalanine과 aspartic acid로 구성된 감미료인 아스파탐(Asp), 3) 녹차의 성분이며 free radical scavenger 및 antioxidant 작용이 있는 polyphenol(PP), 4) 최근 수명연장 효과가 있고 특히 신장질환에 대한 예방효과가 있다고 알려진 aloe 추출물(AE)을 선택하였다. 신장독성을 유발시키기 위하여 OA를 2.0 ㎎/㎏의 용량으로 2주간 연속 경구투여하였다. Phe(40 ㎎/㎏, i.p.)과 Asp(25 ㎎/㎏, p.o.)은 OA(2.0 ㎎/㎏, p.o.)와 병용투여하였으며, PP(200 ㎎/㎏, p.o.)는 OA 투여 2주전부터, AE(50 ㎎/㎏, i.v.)은 3일전부터 전처리하여 OA(2.0 ㎎/㎏, p.o.)와 2주간 병용투여하였다 신장독성의 확인은 혈청중 BUN, creatinine치 및 뇨중 γ-glutamyltranspeptidase와 N-acetyl-β-D-glucosarninidase의 활성을 측정하였고, 신장에 대한 조직병리 검사를 실시하였다. 실험결과, OA를 2주간 2.0 ㎎/㎏용량으로 투여한 결과 신장독성이 유발되었으며, 독성 감소물질로 사용한 4개의 화합물 모두 혈액 및 뇨중 신장독성 지표를 유의성있게 감소시켰다. 조직병리 검사결과 OA에 의하여 신장의 근위세뇨관에 변성이 유발되었으며, 4개의 화합물 처리군에서는 변성이 관찰되지 않았다. 이러한 결과로부터 Phe, Asp, PP및 An는 모두 OA에 의한 신장독성을 감소시킬 수 있으며, OA에 의한 신장독성 유발에는 Phe에 대한 경쟁작용 및 free radical생성이 관여되어 있음을 확인할 수 있었다

본 연구에서는 재래 방법에 따라 생산되고 있는 전통발효식품(된장, 간장, 고추장)에 함유되어 있는 Ochratoxin A(OT-A) 를 면역학적 정량분석법인 Enzyme-Linked Immunosorbent Assay (ELl SA)와 Chemiluminescence Immunoassay(CIA)법을 개발하여 훈석하였다. 각 가정에서 생산하여 소비되는 장류(된장 13종. 간장 12종. 고추장 14종)와 채래척언 방법으로 생산하여 국 내시장에서 유통되고 있는 장류(된장 17종, 간장 11총)로 나누어 분석올 실시하였다.OT-A 흘 정량 조사한 표준독션의 작성 결과 CIA나 ELISA 모두 sensiti까ty는 20 pg/assay 이었으며, 본 실험에서 사용한 면역분석법의 OT-A 회수율은 90% 이상이었다.OT-A 의 잔존량은 가정에서 생산하여 소비되는 시료의 경우 된장 7.1 :t 3.7 ng/g, 간장 2. l:t 2.6 ng/g 그리고 고추장이 4.0 :t 1.9 ng/g 이었으며, 반면 재래시장에 유통되고 있는 시료의 경우 된장이 비교척 잔존량이 높은 22.5 :t 14.0 ng/g, 간장이 16.9:t 4.1 ng/g으로 나타나 가정에서 생산되고 있는 전통발효식품의 경우 OT-A의 오염도가 아주 낮은 것으로 나타났다. 한편 OT-A 의 가옐안정생 시험에서는 60, 90, 121 "c 에서 120 분까지 가열 처리하여 OT-A의 잔존량올 조사하였던 바 121 "c 의 고압처리(1 20 min)에서도 안정하였다.