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1.
ABSTRACT

A reliable, fast and simple method using UHPLC-MS/MS was developed for the determination of aflatoxins B1 (AFB1), G1 (AFG1), B2 (AFB2) and G2 (AFG2), ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEA), HT-2 toxin and T-2 toxin in crude extracts of biscuits with fruit filling, cookies, dried fruits and fruit jams. The method was successfully demonstrated on 39 samples of biscuits with fruit filling, 34 cookies, 14 dried fruits and 10 fruit jams. The mycotoxins detected in biscuits samples were ZEA, OTA, T-2 and AFB1 with an average concentrations of positive samples of 2.64, 4.10, 8.13 and 1.32 µg kg?1, respectively; while the mycotoxins detected in jam samples were AFB1, OTA, T-2 and AFB2 with an average concentrations of positive samples of 2.00, 17.7, 4.37 and 1.15 µg kg?1, respectively. The results showed that the majority of samples were in compliance with relevant regulations. However in eight samples of biscuits and three samples of fig jam the contents of OTA were higher than the existing OTA limits. The combined dietary exposure of selected mycotoxins was estimated for the first time for children, adolescents and adults. The estimated combined dietary exposures were all lower than the proposed value assumed to predict a possible risk scenario.  相似文献   

2.
A new method for the simultaneous quantification of 12 mycotoxins was developed and optimized using reverse phase high performance liquid chromatography (RP-HPLC) with a photodiode array (PDA) and fluorescence detector (FLD), a photochemical reactor for enhanced detection (PHRED) and post-column derivatization. The mycotoxins included aflatoxins (AFB(1), AFB(2), AFG(1), and AFG(2)), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisins (FB(1), FB(2), and FB(3)), T-2 and HT-2 toxins. A double sample extraction with a phosphate-buffered saline solution (PBS) and methanol was used for co-extraction of mycotoxins, and a multifunctional immunoaffinity column was used for cleanup. Optimum conditions for separation of the mycotoxins were obtained to separate 12 mycotoxins in FLD and PDA chromatograms with a high resolution. The method gave recoveries in the range 72-111% when applied to spiked corn samples. The limits of detection (LOD) were 0.025 ng/g for AFB(1) and AFG(1), 0.012 ng/g for AFB(2) and AFG(2), 0.2 ng/g for OTA, 1.5 ng/g for ZEA, 6.2 ng/g for FB(1), FB(3) and HT-2 toxin, 9.4 ng/g for FB(2) and T-2 toxin, and 18.7 ng/g for DON. In addition, the limits of quantification (LOQ) ranged from 0.04 ng/g for AFB(2) and AFG(2) to 62 ng/g for DON. The method was successfully applied to the determination of these mycotoxins in 45 cereal samples obtained from the Malaysian market. The results indicated that the method can be applied for the multi-mycotoxin determination of cereals.  相似文献   

3.
Contamination of barley by moulds and mycotoxins results in quality and nutritional losses and represents a significant hazard to the food chain. The presence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) and ochratoxin A (OTA) in stored barley in Spain has been studied. Species-specific PCR assays were used for detection of Aspergillus flavus, A. parasiticus, A. ochraceus, A. steynii, A. westerdijkiae, A. carbonarius and A. niger aggregate in mycotoxin-positive barley samples at different incubation times (0, 1 and 2 days). Classical enumeration techniques (CFU/g) in different culture media for evaluation of Aspergillus in sections Flavi, Circumdati and Nigri were also used. One hundred and five barley kernel samples were collected in Spanish grain stores from 2008 to 2010, and analyzed using a previously optimized method involving accelerated solvent extraction, cleanup by immunoaffinity column, liquid chromatographic separation, post-column derivatization with iodine and fluorescence detection. Twenty-nine samples were contaminated with at least one of the studied mycotoxins. AFB1, AFB2, AFG1, AFG2, and OTA were detected in 12.4%, 2.9%, 4.8%, 2.9%, and 20% of the samples, respectively. Aflatoxins and OTA co-occurred in 4.8% of the samples. Maximum mycotoxin levels (ng/g) were 0.61 (AFB1), 0.06 (AFB2), 0.26 (AFG1), 0.05 (AFG2), and 2.0 (OTA). The results of PCR assays indicated the presence of all the studied species, except A. westerdijkiae. The PCR assays showed high levels of natural contamination of barley with the studied species of Aspergillus which do not correspond to the expected number of CFU/g in the cultures. These results suggest that a high number of non-viable spores or hyphae may exist in the samples. This is the first study carried out on the levels of aflatoxins and OTA in barley grain in Spain. Likewise, this is the first report on the presence of aflatoxigenic and ochratoxigenic Aspergillus spp. in barley grain naturally contaminated with those mycotoxins using a species-specific PCR approach.  相似文献   

4.
The aim of this study was to determine the co-occurrence of aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA) in paprika and chilli samples purchased in Spain, using HPLC with fluorescence detection. The occurrence of mycotoxin in 64 paprika samples was 59% for AFs, 98% for OTA and 39% for ZEA, whereas in the 35 chilli samples, the contamination was 40% for AFs, 100% for OTA and 46% for ZEA. None of the samples had AFs levels higher than the legally allowable limits. Regarding the co-occurrence of mycotoxins, 75% of paprika samples and 65% of chilli samples contained more than one mycotoxin. Chilli samples generally had lower concentrations of AFB1, AFB2, total AFs and OTA than had paprika samples. The high incidence of OTA contamination suggests that additional legislation may be required to for these kinds of spices.  相似文献   

5.
Method validation for quantitative analysis of aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA) in cereals using HPLC with fluorescence detector (FLD) is described. Mycotoxins were extracted with methanol?:?water (80?:?20) and purified with a multifunctional AOZ immunoaffinity column before HPLC analysis. The validation of the analytical method was performed to establish the following parameters: specificity, selectivity, linearity, limits of detection (LOD) and quantification (LOQ), accuracy, precision (within- and between-day variability), stability, robustness, measurement of performance, and measurement of uncertainty. Calibration curves were linear (r?>?0.999) over the concentration range, from the LOQ to 26, 40 and 400?ng/g for AFs, OTA and ZEA, respectively. LOD and LOQ were 0.0125 and 0.05?ng/g for aflatoxin B1 (AFB1) and G1 (AFG1), 0.0037 and 0.015?ng/g for aflatoxin B2 (AFB2) and G2 (AFG2), as well as 0.05 and 0.2?ng/g for OTA and 0.5 and 2?ng/g for ZEA, respectively. The mean recovery values were 77–104% for different concentrations of AFs, OTA and ZEA in spiked cereal samples. Both intra- and inter-day accuracy and precision were within acceptable limits. This method was successfully applied for the simultaneous determination of mycotoxins for 60 cereal samples collected from Malaysian markets. Fifty per cent of the cereal samples were contaminated with at least one of these mycotoxins, at a level greater than the LOD. Only one wheat sample and two rice samples were contaminated with levels greater than the European Union regulatory limits for AFs and OTA (4 and 5?ng/g). The means and ranges of mycotoxins obtained for the cereal samples were 0.4?ng/g and 0.01–5.9?ng/g for total AFs; 0.18?ng/g and 0.03–5.3?ng/g for OTA; and 2.8?ng/g and 2.4–73.1?ng/g for ZEA, respectively. The results indicate that the method is suitable for the simultaneous determination of AFs, OTA and ZEA in cereals and is suitable for routine analysis.  相似文献   

6.
Method validation for quantitative analysis of aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA) in cereals using HPLC with fluorescence detector (FLD) is described. Mycotoxins were extracted with methanol : water (80 : 20) and purified with a multifunctional AOZ immunoaffinity column before HPLC analysis. The validation of the analytical method was performed to establish the following parameters: specificity, selectivity, linearity, limits of detection (LOD) and quantification (LOQ), accuracy, precision (within- and between-day variability), stability, robustness, measurement of performance, and measurement of uncertainty. Calibration curves were linear (r > 0.999) over the concentration range, from the LOQ to 26, 40 and 400 ng/g for AFs, OTA and ZEA, respectively. LOD and LOQ were 0.0125 and 0.05 ng/g for aflatoxin B1 (AFB1) and G1 (AFG1), 0.0037 and 0.015 ng/g for aflatoxin B2 (AFB2) and G2 (AFG2), as well as 0.05 and 0.2 ng/g for OTA and 0.5 and 2 ng/g for ZEA, respectively. The mean recovery values were 77-104% for different concentrations of AFs, OTA and ZEA in spiked cereal samples. Both intra- and inter-day accuracy and precision were within acceptable limits. This method was successfully applied for the simultaneous determination of mycotoxins for 60 cereal samples collected from Malaysian markets. Fifty per cent of the cereal samples were contaminated with at least one of these mycotoxins, at a level greater than the LOD. Only one wheat sample and two rice samples were contaminated with levels greater than the European Union regulatory limits for AFs and OTA (4 and 5 ng/g). The means and ranges of mycotoxins obtained for the cereal samples were 0.4 ng/g and 0.01-5.9 ng/g for total AFs; 0.18 ng/g and 0.03-5.3 ng/g for OTA; and 2.8 ng/g and 2.4-73.1 ng/g for ZEA, respectively. The results indicate that the method is suitable for the simultaneous determination of AFs, OTA and ZEA in cereals and is suitable for routine analysis.  相似文献   

7.
The efficiency of three extraction solvents and three clean-up procedures was compared for simultaneous extraction and purification of aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), and zearalenone (ZEA) from spiked cereal samples. The best recovery rates for all mycotoxins were achieved using methanol: water (80:20) as the extraction solvent and AOZ multi-functional immunoaffinity column (IAC), as clean up method with recovery values of 61–89%, while that of Oasis HLB and MycoSep 226 were 37–67% and 44–78%, respectively. Then, five variables in the IAC clean-up conditions, including primary conditioning with phosphate buffer saline (PBS) (0–10 mL) (X1), extract load up volume (10–20 mL) (X2), washing volume with PBS (10–20 mL) (X3), and eluting solution volumes with methanol (1–3 mL) (X4) and acetic acid (0–1.5 mL) (X5), were optimized for the specific purification and enrichment of the mycotoxins. Results showed that primary conditioning and PBS washing did not have a significant effect on the recovery responses of mycotoxins. Optimized conditions were selected as 0, 15, 10, 1.3, and 1.5 mL for X1–X5, respectively. The recovery rates of AFB1, AFB2, AFG1, AFG2, OTA and ZEA were within 93–104% in spiked rice, under optimal conditions. LOD and LOQ were 0.0125 and 0.05 ng/g for AFB1 and AFG1, 0.0037 and 0.015 ng/g for AFB2 and AFG2, 0.05 and 0.2 ng/g for OTA, and 0.5 and 2 ng/g for ZEA, respectively. Extraction of spiked cereal samples with methanol: water (80:20) and clean up using AOZ IAC column in optimal condition provided recovery range of 77–104% for all targeted mycotoxins.  相似文献   

8.
A fast and simple UHPLC-FLD method has been developed for the simultaneous determination in barley of aflatoxins (B1, G1, B2 and G2), ochratoxin A (OTA) and zearalenone (ZEA), some of the most important mycotoxins due to their toxicity and occurrence. The procedure is based on the extraction of the six mycotoxins with a mixture of acetonitrile and water, and the purification of the extract with immunoaffinity columns before analysis. Detection of AFB1 and AFG1 is improved using a photochemical reaction. The method has been validated with satisfactory results. Limits of detection were 340 ng kg−1 for ZEA, 13 ng kg−1 for OTA and varied from 0.5 to 15 ng kg−1 for aflatoxins. Recovery percentages were between 78.2% and 109.2%. After being validated, the method has been successfully applied to 20 barley samples cultivated in a region of northern Spain (Navarra).  相似文献   

9.
ABSTRACT

Occurrence of aflatoxins (AFs) AFB1, AFB2, AFG1, AFG2 and ochra toxin A (OTA) was studied in 65 samples of stored and freshly harvested wheat, barley and maize collected in Tunisia. The mycotoxins were simultaneously extracted and quantified by high performance liquid chromatography. Determination of AF-producing (section Flavi) and OTA-producing Aspergillus species (sections Nigri and Circumdati) was conducted in these samples by species-specific polymerase chain reaction (PCR). Results showed that most of maize samples were contaminated with AFs, data after storage showing lower values than those collected at harvest. All contaminated maize samples contained AFG1 and AFG2, among which 27.78% also had AFB1 and AFB2. This AFs pattern was consistent with the A. parasiticus toxin profile. A. flavus however showed the highest frequency in maize but was also found in barley and wheat where no AFs were detected. In contrast, OTA was neither found in maize nor in barley and only one wheat sample contained OTA. A. niger was the only OTA-producing species detected.  相似文献   

10.
针对市场在售的调和油、玉米油、大豆油、花生油和菜籽油等食用植物油,随机购买20种共290份食用植物油样品。采用液相色谱法测定AFB_(1)、AFB_(2)、AFG_(1)、AFG_(2)以及OTA、OTB真菌毒素的含量,对食用植物油中黄曲霉毒素和赭曲霉毒素的污染水平和分布特征进行分析。结果表明:20种290份食用植物油样品中,有16种共67份样品存在不同程度的真菌毒素污染,总污染率达到23.1%,不同种类食用植物油污染呈现“多种类、共分布”的特点,其中AFG_(1)污染率(14.8%)最高,其次为OTA(13.4%)。绝大多数阳性样本受1~4种真菌毒素污染,仅有少数阳性样本受真菌毒素污染数量达到5种。总体上食用植物油样品受到多种真菌毒素的混合污染情况比较严重,应引起一定的重视。  相似文献   

11.
目的 了解重庆地区辣椒、花椒和八角中真菌毒素污染状况。方法 采用随机抽样方法,在重庆地区盘溪、菜园坝和江津三个市场,抽取180批次香辛料样品,采用HPLC-MS/MS检测黄曲霉毒素(AFB1、AFB2、AFG1和AFG2)、赭曲霉毒素A(OTA)和伏马毒素(FB1和FB2)。结果 重庆地区辣椒、花椒和八角中的真菌毒素总检出率分别为60.0%、100%、96.7%。AFs和OTA是三种香辛料最主要的污染毒素,其中AFG2是最主要的黄曲霉代谢产物。盘溪市场的AFs污染总体情况稍好,菜园坝市场AFs污染最严重;江津市场的OTA污染最为严重。结论 香辛料中存在真菌毒素污染,有必要建立香辛料中真菌毒素的限量标准。  相似文献   

12.
杨琳  张宇昊  马良 《食品科学》2010,31(24):250-254
建立粮谷类食品中黄曲霉毒素(B1、B2、G1 和G2)和赭曲霉毒素A 的同时检测方法。样品经过甲醇- 水(80:20,V/V)提取,液液萃取净化和富集后,三氟乙酸衍生,采用Agilent ZORBAX SB-C18 色谱柱(4.6mm ×250mm),以乙腈和体积分数2% 冰醋酸溶液为流动相梯度洗脱,在线变换波长荧光检测。根据3 倍信噪比的峰 响应值,确定黄曲霉毒素(B1、B2、G1 和G2)和赭曲霉毒素A 检出限分别为0.06、0.03、0.18、0.05μg/kg 和0.51μg/kg,上述5 种毒素分别在质量浓度0.05~100、0.125~25.00、0.05~100、0.125~25.00μg/L 和0.05~50.00μg/L 范围内呈线性相关,相关系数r 分别为0.9998、0.9998、0.9998、0.9996 和0.9998;在玉米、大米、小麦3 类样品中加标回收率平均为71.73%~115.37%,相对标准偏差为3.00%~9.88%,方法学验证结果表明,黄曲霉毒素和赭曲霉毒素A 5 种毒素同时检测结果与现行国标的单独检测方法检测结果无显著性差异(P > 0.05)。  相似文献   

13.
Mycotoxins are products of moulds that frequently contaminate maize. In this study the presence of mycotoxins fumonisin B1 (FB1), fumonisin B2 (FB2), zearalenone (ZEA) and ochratoxin A (OTA) was determined in 49 maize grain samples collected in autumn 2002. The most frequent finding was that of FB1(100%), followed by ZEA (84%) and OTA (39%), while FB2 was found only in three samples. The co-occurrence of two and three mycotoxins was found in 55 and 37% of samples, respectively. The concentrations (mean ± SD) of FB1, ZEA and OTA in positive samples were 459.8 ± 310.7, 3.84 ± 6.68 and 1.47 ± 0.38 µg kg-1, respectively, and the concentrations of FB2 in three positive samples were 68.4, 109.2 and 3084.0 µg kg-1. Although such low concentrations of mycotoxins are not a significant source of exposure in countries with a European diet, a few samples with extreme values indicate that thorough control is needed.  相似文献   

14.
This survey examined 60 samples of sorghum and 30 samples of sorghum products from three states (Khartoum, Kordofan and Gadarif) of Sudan for aflatoxin B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2), ochratoxin A and B (OTA, OTB) and zearalenone (ZEN), using high performance liquid chromatography with fluorescence detection. The limits of detection and limits of quantification were in the range 0.01–0.6 µg kg–1 and 0.03–2.0 µg kg?1, respectively. The frequency of contaminated samples with AFB1 from Khartoum, Gadarif and Kordofan state was 38.1%, 22.2% and 23.8%, respectively. Only two samples of sorghum from Khartoum state were contaminated with OTA (3.3%). Concentrations of OTA and OTB were low and may not cause problems. No sample of sorghum or sorghum products was contaminated with ZEN. Some sorghum samples contained AFB1 concentrations above the European Union regulatory limits. The highest contaminated samples were found in Khartoum state.  相似文献   

15.
A methodology was developed to quantify the efficiency of yeast-based products for adsorption of three mycotoxins: zearalenone (ZEA), aflatoxin B(1) (AFB(1)), and ochratoxin A (OTA). Eight products were tested (yeast cell wall or inactivated yeast). The described experimental protocol based on in vitro tests provided reliable isotherms for each mycotoxin. The most suitable models were the Hill model for ZEA, the Langmuir model for AFB(1), and the Freundlich model for OTA. From these models, original mathematical affinity criteria were defined to quantify the product adsorption performances for each mycotoxin. The best yeast product, a yeast cell wall from baker's yeast, can adsorb up to 68% of ZEA, 29% of AFB(1), and 62% of OTA, depending on the mycotoxin concentrations. The adsorption capacity largely depended both on yeast composition and mycotoxin, but no direct correlation between yeast composition and adsorption capacity was found, confirming that adsorption of mycotoxin on yeast-based products involves complex phenomena. The results of this study are useful for comparing the adsorption efficiency of various yeast products and understanding the mechanisms involved in adsorption.  相似文献   

16.
A simple and sensitive method has been developed for simultaneous determination of aflatoxins (AFB1, AFB2, AFG1, and AFG2) and ochratoxin A (OTA) in bee pollen. The analytes in the sample were extracted with a mixture of acetonitrile/water (60:40, v/v), using low temperature for fat precipitation, followed by immunoaffinity column cleanup of extracts. The mycotoxins were quantified using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with an electrospray ionization (ESI) and a triple quadrupole (QqQ) analyzer. Matrix effect, accuracy, and precision were evaluated and achieved good results calculated by matrix-matched calibration standards which reduced the influence of matrix effect. Recoveries at three levels were in the range of 74.3–96.5 % with RSD less than 10.0 %. The correlation coefficients (r 2) of the five mycotoxins were higher than 0.997. The method showed high sensitivity with LOD below 0.05 μg/kg.  相似文献   

17.
This report presents data on the occurrence of aflatoxins (AF) and ochratoxin A in different types of flour marketed in Serbia. A total of 114 samples of wheat, buckwheat, rye, oat, barley, rice, millet and corn flour were collected in the period 2012–2016 and analysed using high performance liquid chromatography with fluorescence detection. Among flours other than corn, AFB1 was quantified only in rice, while ochratoxin A (OTA) was found in 29% of the samples. In corn flours the percentage of positive samples varied greatly over the years: AFB1 7.1–80.0%, OTA 30.0–40.6%, with a co-occurrence of 7.1–34.4%. Overall 5.2% of flours other than corn and 10.7% of corn flours exceeded the maximum levels (MLs) for AFB1 and/or OTA. The highest recorded levels were 8.80 μg kg?1 of AFB1 (corn) and 23.04 μg kg?1 of OTA (rye). Overall mean contamination levels of corn flours were 0.53 μg kg?1 of AFB1 and 0.46 μg kg?1 of OTA.  相似文献   

18.
Sorghum samples (n = 60) from Tunisian markets were analysed for the occurrence of 22 of both traditional and emerging mycotoxins. Samples were extracted with a QuEChERS-like method and mycotoxins were detected by LC-MS/MS. This method was validated and adequate analytical parameters were obtained. All samples had contamination with mycotoxins and several samples had higher contamination levels than European Union legislative limits (MLs). The most frequently found mycotoxins were ENB (100%), OTA (98%), ENA1 (63%), ENB1 (56%), BEA (48%), AFB1 (38%) and STG (33%). Mean contaminations were 30.7, 1.93, 33.2, 51.0, 15.4, 1.49 and 20.5 µg kg–1, respectively. While two samples were contaminated with FB2 and FB3 at mean values of 16.2 and 45.9 µg kg–1, respectively, one sample was contaminated with AFB2 and ZEA at levels of 0.82 and 45.0 µg kg–1, respectively. The results were used to estimate the daily intake of mycotoxins through sorghum consumption with regard to normal consumers (low-risk population) and high consumers such as babies (high-risk consumers) who are facing an alarming situation.  相似文献   

19.
Aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) were extracted by matrix solid-phase dispersion with C18 silica and acetonitrile as the eluting solvent, analysed by liquid chromatography with fluorescence detection and confirmed by liquid chromatography with mass spectrometry using an electrospray interface in 58 samples grouped as cereals, dried fruits, herbs and spices, pulses, snacks, and nuts and nut products collected from local markets and supermarkets in Valencia, Spain. All samples analysed by the proposed method were previously studied with an enzyme-linked immunosorbent assay as a screening protocol for the fast detection of mycotoxins. The samples containing residues (3/58) were hazelnut (0.42 and 0.52 μg kg-1 for AFB1 and AFG1, respectively), nut cocktail (0.29 and 0.47 μg kg-1 for AFB1 and AFG1, respectively) and pinhol (0.30 μg kg-1 for AFG1). Such values were below the legislated maximum residue levels for the European Union.  相似文献   

20.
丁学妍  邵瑞婷  张涵璐 《食品科学》2022,43(24):325-334
运用基质分散固相萃取净化,建立牛奶中24 种真菌毒素(黄曲霉毒素B1、黄曲霉毒素B2、黄曲霉毒素G1、黄曲霉毒素G2、黄曲霉毒素M1、赭曲霉毒素A、玉米赤霉烯酮、玉米赤霉酮、α-玉米赤霉烯醇、β-玉米赤霉烯醇、α-玉米赤霉醇、β-玉米赤霉醇、T-2毒素、HT-2霉素、伏马毒素B1、伏马毒素B2、伏马毒素B3、脱氧雪腐镰刀菌烯醇、3-乙酰脱氧雪腐镰刀菌烯醇、15-乙酰脱氧雪腐镰刀菌烯醇、交链孢霉单甲基醚、交链孢酚、腾毒素、细交链孢菌酮酸)多残留检测的超高效液相色谱-串联质谱检测方法。样品经80%乙腈溶液(体积分数)提取,通过基质分散固相萃取净化,氮吹至近干,1 mL 50%乙腈溶液(体积分数)复溶,采用超高效液相色谱-串联质谱进行测定。经ACQUITY UPLC HSS T3反相柱(2.1 mm×100 mm,1.8 μm)分离,梯度洗脱,采用电喷雾离子源-多反应监测模式采集。24 种目标物的相关系数(R2)均大于0.985,加标回收率为71.0%~123.0%,相对标准偏差均小于10%。该方法具有操作简单、重复性好、灵敏度高、杂质干扰小等特点,可以用于牛奶中24 种真菌毒素的检测。  相似文献   

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