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1.
The presence of Aspergillus section Flavi and aflatoxin (AF) contamination was investigated in 112 samples of peanuts, almonds and dried figs collected in Algeria. The occurrence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) in different commodities has been determined with a sensitive method based on high performance liquid chromatography (HPLC) coupled with fluorescence detection with post-column photochemical derivatisation. Analytical results indicated that 28 samples of peanuts, 16 samples of almonds and 26 samples of dried figs contained detectable levels of AFs. A total of 69 samples (61.6%) were contaminated with AFB1 ranging from the limit of quantification to 174 µg kg?1. AFB2 was found in 12 samples (10.7%) and varied from 0.18 to 193 µg kg?1. Seven samples revealed AF concentrations lower than the limit of quantification. Eleven peanut and fourteen dried fig samples exceeded the European maximum limits for AFB1.  相似文献   

2.
Mycoflora, the mycotoxigenic properties of moulds, and natural contamination with mycotoxins such as aflatoxins (AFs), cyclopiazonic acid (CPA), fumonisin B(1) (FB(1)) and ochratoxin A (OTA) were investigated in dried figs. Dry fig samples were collected from orchards during the drying stage in the Aegean Region of Turkey. Fungal isolates were identified using morphological, chemical as well as molecular methods. Mycotoxigenic characteristics of moulds were assessed by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Mycotoxins except CPA (by TLC) were determined by HPLC. All the fig samples were contaminated with moulds and 94.7% contained one or more mycotoxigenic species. The most prevalent moulds present in dried figs belong to the Aspergillus section Nigri members, being 93.9% positive for the samples, followed by Fusarium spp., Aspergillus section Flavi and Penicillium spp. On the other hand, Fusarium spp. had the highest count and the number of fumonisin producing Fusarium was also high. A total of 48% of 115 dried fig samples contained OTA (range = 0.1-15.3 ng g(-1)), 74.7% of the samples had FB(1) (range = 0.05-3.65 mg kg(-1)), 10.0% of the samples had aflatoxin (range = 0.1-763.2 ng g(-1)) and 24.3% of the samples were tentatively identified as being contaminated with CPA (range = 25-187 ng g(-1)). Dried fig samples were contaminated with one (33.0%), two (47.0%), three (5.2%) and four mycotoxins (3.5%). A total of 11.3% of dried fig samples were not contaminated with any of the four mycotoxins. To the best of our knowledge, CPA and fumonisin have been found for the first time in dried figs.  相似文献   

3.
Dried figs for export from Turkey from crop years 2003 through 2006 were tested for aflatoxin B1 and total aflatoxins. For export to the European Union, consignments of 0.5 to 10 tonnes of dried figs were sampled according to European Commission regulations, and high-pressure liquid chromatography (HPLC) was used to determine concentrations of aflatoxins Bl, B2, G1, and G2. For each consignment of dried figs, a 30-kg sample (comprising 100 subsamples) was divided into three 10-kg subsamples, which were separately blended and analyzed with HPLC. This monitoring effort was conducted for figs from 2003, 2004, 2005, and up to June 2006, for a total of 10,396 30-kg samples (28,489 analyses). The incidence of contamination with aflatoxin B1 at higher than 2 ng/g was on average 0.6, 2.0, 4.0, and 2.4% for 2003, 2004, 2005, and up to June 2006, respectively, whereas contamination with total aflatoxins at higher than 4 ng/g was 2.6, 3.0, 5.1, and 2.7%. There was significant variability in contamination between replicate 1-kg samples, indicating small numbers of individual contaminated figs were probably responsible. There were also substantial differences in the relative proportions of aflatoxins B1, B2, G1, and G2 among samples, suggesting different contributing fungal sources.  相似文献   

4.
Samples of dried figs and fig pastes from Turkey supplied voluntarily by UK importers and retailers during the period November 1988 to January 1989 showed both a high incidence and high levels of contamination with aflatoxins. In the samples tested, 24% had total aflatoxin concentrations above 10 micrograms/kg, with the highest level being 165 micrograms/kg. More rigorous monitoring of the 1989 fig harvest was undertaken on bulk consignments for all figs from Turkey entering the UK. For whole dried figs 20 kg samples were taken (as 20 sub-samples), and for fig paste 5 kg samples were taken (again as 20 sub-samples). Figs were minced, blended with water and mixed prior to sub-sampling for analysis. Analysis was by immunoaffinity column clean-up with HPLC determination of aflatoxins with fluorescence detection. Examination showed that 11% of 112 consignments of fig paste and 9% of 93 consignments of whole dried figs were contaminated with total alfatoxin concentrations above 10 micrograms/kg, with the highest level of contamination being 40 micrograms/kg. As a result of this surveillance programme 14 consignments of figs were refused entry into the United Kingdom.  相似文献   

5.
Dried figs of three different categories, palatable, fluorescent, and cull, were investigated for their contents of aflatoxins (B(1), B(2), G(1) and G(2)), patulin, and ergosterol. Samples were obtained from four fig processing plants located in a major fig producing area in the Aegean Region in Turkey. Affinity column clean-up methods were employed for aflatoxins. All aflatoxins, patulin, and ergosterol were determined using high performance liquid chromatography. Palatable figs contaminated with trace amounts of aflatoxins, patulin, and ergosterol, so they posed no risk for the consumer when national and/or international regulatory limits were considered. Fluorescent figs were contaminated with high (117.9-471.9 ppb) aflatoxin levels and cull figs with high patulin (39.3-151.6 ppb) and ergosterol (4.5-18 ppm) levels. The total aflatoxins content was significantly correlated with the patulin content (r(2) = 0.813, p < 0.002) and the ergosterol content (r(2) = 0.920, p < 0.002) only in fluorescent figs. However there was no significant correlation between patulin and ergosterol contents of fluorescent figs. Furthermore, there were no significant correlations between the contents of any two of the three substances in cull figs. This is the first report on the presence of patulin and its co-occurrence with aflatoxin in dried figs.  相似文献   

6.
Mycoflora, the mycotoxigenic properties of moulds, and natural contamination with mycotoxins such as aflatoxins (AFs), cyclopiazonic acid (CPA), fumonisin B1 (FB1) and ochratoxin A (OTA) were investigated in dried figs. Dry fig samples were collected from orchards during the drying stage in the Aegean Region of Turkey. Fungal isolates were identified using morphological, chemical as well as molecular methods. Mycotoxigenic characteristics of moulds were assessed by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Mycotoxins except CPA (by TLC) were determined by HPLC. All the fig samples were contaminated with moulds and 94.7% contained one or more mycotoxigenic species. The most prevalent moulds present in dried figs belong to the Aspergillus section Nigri members, being 93.9% positive for the samples, followed by Fusarium spp., Aspergillus section Flavi and Penicillium spp. On the other hand, Fusarium spp. had the highest count and the number of fumonisin producing Fusarium was also high. A total of 48% of 115 dried fig samples contained OTA (range?=?0.1–15.3?ng?g?1), 74.7% of the samples had FB1 (range?=?0.05–3.65?mg?kg?1), 10.0% of the samples had aflatoxin (range?=?0.1–763.2?ng?g?1) and 24.3% of the samples were tentatively identified as being contaminated with CPA (range?=?25–187?ng?g?1). Dried fig samples were contaminated with one (33.0%), two (47.0%), three (5.2%) and four mycotoxins (3.5%). A total of 11.3% of dried fig samples were not contaminated with any of the four mycotoxins. To the best of our knowledge, CPA and fumonisin have been found for the first time in dried figs.  相似文献   

7.
Aflatoxin B1-contaminated fruits were sorted out from 250 kg dried figs (five Turkish and three Greek batches) by bright-greenish-yellow fluorescence under UV light. The aflatoxins of the fluorescent figs were extracted by simple soaking in methanol. Aflatoxin B1 was determined by thin-layer chromatography. Parallel to this, an extraction for the determination of aflatoxin B1 was developed by a competitive ELISA and the two methods were compared with each other. In a highly contaminated batch of Turkish figs, statistically there was one fig among 350 which had a high aflatoxin content (greater than 100 ng/g fig) and one fig amongst 140 fruits with an aflatoxin B1 content of greater than 10 ng B1/g fig.  相似文献   

8.
Mould growth and mycotoxin (aflatoxins and ochratoxin A) formation were examined in the 1993 dried figs crop. The relationships between mould/mycotoxin contamination and orchard conditions, different harvesting techniques, harvesting time and intactness of fruits were investigated. The fruits were examined during drying and effects of different pretreatments, sun drying and solar drying on the mould and mycotoxin contamination in figs were also studied. Aflatoxins (B1, B2, G1 and G2) were not present in the firm or shrivelled ripe figs. Among the samples examined during drying, only one of the 32 samples was found to be aflatoxin positive. Ochratoxin A was not detected in any of the samples analysed. The moisture content, aw and pH values of full ripe and shrivelled fruits were suitable for mould growth and mycotoxin formation while these parameters in pretreated and dried fruits were found to be too low to allow such outcome. It was observed that harvesting the fruit by hand-treating with different solutions and application of solar drying were effective in reducing contamination level.  相似文献   

9.
A survey was carried out to determine the co-occurrence of ochratoxin A and aflatoxin B1 in dried figs from Turkey. Samples from two seasons of crops (2003 and 2004) intended for export to the European Union and the 2004 crop obtained from the domestic Turkish market were analyzed. Affinity column cleanup methods were employed for determining separately ochratoxin A and aflatoxin B1, but for ochratoxin A an alkaline extraction procedure was employed (in contrast to the conventionally employed acidic extraction), which gave consistently higher toxin recovery. In-house validation of the ochratoxin A method gave a limit of detection of 0.15 ng/g and a limit of quantification of 0.5 ng/g with a repeatability of 5.8% in the range 5 to 10 ng/g (with a mean recovery of 94% for spiked samples). Positive results for ochratoxin A were confirmed by liquid chromatography-mass spectrometry. For the 2003 export figs (58 samples), 7 samples contained only aflatoxin B1, 2 samples contained only ochratoxin A, and 2 samples contained both toxins (with maximum concentrations of 35.1 ng/g for aflatoxin B1 and 13.0 ng/g for ochratoxin A). Similarly for the 2004 export figs (41 samples), 16 samples contained only aflatoxin B1, 4 samples contained only ochratoxin A, and 2 samples contained both toxins (with maximum concentrations of 20.6 ng/g for aflatoxin B1 and 26.3 ng/g for ochratoxin A). Of 20 retail samples of dried figs from Turkey, only one sample contained ochratoxin A (2.0 ng/g) and none were contaminated with aflatoxin B1. This survey revealed a 14 to 15% incidence of occurrence of ochratoxin A for 2 years, which is higher than previously reported.  相似文献   

10.
Dried figs are sensitive commodities to aflatoxin contamination. Although preventive methods are the logical solution to aflatoxin problems, once the product is contaminated, decontamination procedures are inevitable. In this study, the effectiveness of a procedure consisted of acidification/alkalization, and heat treatment in degradation of aflatoxins was evaluated. The pH of dried fig extracts was adjusted to 3.1, 3.5, 6, 8 or 10 by adding acid or base. Extracts were heated at 50, 75 or 98C for 1 or 2 h, and then the residual aflatoxin B1, B2, G1 and G2 were determined. The highest level of degradation for aflatoxin B1 (97  ±  1%) and B2 (87  ±  1%) were observed at pH 10 in samples heated at 98 and 50C, respectively. Some treatments resulted in 100% degradation of aflatoxin G1 and G2 so that they could not be detected.

PRACTICAL APPLICATIONS


Aflatoxin contamination is a serious problem for a number of processed and non-processed foods, including dried figs. This not only presents severe risks to human and animal health but also causes economic problems for countries such as Turkey, U.S.A., Greece and Spain, which produce and export dried figs. It is clear that detoxifying studies are unavoidable when the amount of crop contaminated by toxins is considered. Therefore, the food industry is in search of applications that are effective in mycotoxin detoxification and adaptable to food processes. This is the first report on degradation of aflatoxins in naturally contaminated dried figs by such a promising method.  相似文献   

11.
To determine differences in mean aflatoxin contamination and subsample variance from dry and slurry homogenizations, 10 kg of six different, naturally contaminated dried fig samples were collected from various exporting companies in accordance with the EU Commission Directive. The samples were first dry-mixed for 5 min using a blender and sub-sampled seven times; the remainder was slurry homogenized (1 : 1, v/v) and sub-sampled seven times. Aflatoxin B1 and total aflatoxin levels were recorded and coefficient of variations (CV) computed for all sub-samples. Only a small reduction in sub-sample variations, indicated by the lower CV values, and slight differences in mean aflatoxin B1 and total aflatoxin levels were observed when slurry homogenization was applied. Therefore, 7326 dried figs, destined for export from Turkey to the EU and collected during the 2008 crop year, were dry-homogenized and tested for aflatoxins (B1, B2, G1 and G2) by immunoaffinity column clean-up using RP-HPLC. While 34% of the samples contained detectable levels of total aflatoxins (0.20–208.75 µg kg?1), only 9% of them exceeded the EU limit of 4 µg kg?1 in the range 2.0–208.75 µg kg?1, respectively. A substantial increase in the incidence of aflatoxins was observed in 2008, most likely due to the drought stress experienced in Aydin province as occurred in 2007.  相似文献   

12.
Fresh and dried figs are important components of the Mediterranean diet. In Cilento (Southern Italy), figs belonging to cultivar “Dottato” are used for the production of “PDO Cilento white figs,” as dried figs. In this article, we reported the characterization of the phenolic compounds in 19 fig samples: 9 fresh figs cultivar “Dottato” from Cilento (Italy), 10 dried fig samples from Cilento (2), Turkey (6), and Greece (2). The following phenolic compounds were identified and quantified by high‐performance liquid chromatography (HPLC)/UV‐DAD: chlorogenic acid, protocatechuic acid, vanillic acid, luteolin‐3,7‐di‐O‐glucoside, luteolin 7‐glucoside, apigenin‐7‐O‐rutinoside, rutin, quercetin‐3‐glucoside, and cyanidin‐3‐O‐rutinoside. A discriminative analysis between the peel and pulp of the samples was carried out. The 1st crop (“breba”) and the 2nd one (full crop) from Dottato figs were considered, as well as the effect of fig pollination. The majority of the phenolic compounds were predominant in the fig peel. Significant quantitative differences were found among fresh figs, whereas also some qualitative differences were obtained between fresh and dried figs from the same origin in Dottato cultivar, and among dried figs from different origins. Breba crop resulted richer in phenolics than figs of the 2nd crop. Considering the dried figs, the Turkish ones had the highest concentration in phenolic compounds. Other compounds such as the aminoacids tyrosine and tryptophan were also detected by HPLC‐DAD analysis in Dottato figs, probably due to the similarity of their chemical structure.  相似文献   

13.
Two hundred and fourteen unprocessed corn samples (1997-98 harvest), collected at wholesale markets in different regions in Brazil, were surveyed for the occurrence of mycotoxins. The samples were analysed for aflatoxins B 1 , B 2 , G 1 , G 2 , zearalenone and fumoni1sin B 1 using in-house validated methods. The occurrence of aflatoxin B 1 , zearalenone and fumonisin B 1 was found in 38.3, 30.4 and 99.1% of the samples, respectively. Aflatoxin B 1 , zearalenone and fumonisin B 1 contamination levels varied from 0.2 to 129, 36.8 to 719, and 200 to 6100 μg/kg, respectively. The cooccurrence of the two carcinogenic mycotoxins aflatoxin B 1 and fumonisin B 1 was observed in 100% of the aflatoxin-contaminated samples (82 samples). Cooccurrences of aflatoxin B 1 : zearalenone: fumonisin B 1 and aflatoxin B 1 : aflatoxin B 2 : fumonisin B 1 were found in 18 and 43 samples, respectively.  相似文献   

14.
The mold flora of 50 dried fig samples consumed in Turkey was examined and the aflatoxigenic ones were determined. Among 127 fungi isolated, 74 were Aspergillus, 24 were Trichoderma, 16 were Fusarium and 13 were Acremonium. Of the isolates, 17 were aflatoxigenic and four of them were capable to produce aflatoxin, three of which were characterized as A. flavus and one as A. parasiticus. Aflatoxin production of four strains was confirmed by high pressure liquid chromotography. The effect of UV irradiation on mold count and aflatoxin quantity was also tested. It was found that UV irradiation led to a decrease in the mold count and aflatoxin quantity.

PRACTICAL APPLICATIONS


Studies have shown that the concentration of aflatoxins may exceed the determined limits in dried figs. Its presence can be a potential threat to the health of consumers. Dried figs are one of the major agricultural export products of Turkey ( Senyuva et al. 2005 ). The effects of UV irradiation on mold flora of dried figs and aflatoxins have been examined. The Aspergillus flavus and parasiticus agar (AFPA) medium is used for detection of aflatoxigenic species, and coconut agar medium (CAM) is used to detect the aflatoxin-producing ability of aflatoxigenic strains. It was found that the reproduction of the molds in dried figs, consequently the aflatoxigenic mold strains, can be depressed by UV irradiation. It was found that increasing time of UV irradiation led to a decrease in the mold count in dried figs. In addition, a UV irradiation applied for 90 min, was found to decrease the aflatoxin quantity in dried figs in an amount of 25%. Because of inexpensiveness and easiness of the application it was concluded that the UV irradiation can be used as a practical application.  相似文献   

15.
周丽  杨清山  连运河  王磊  张晓芳 《食品科学》2016,37(14):165-168
利用免疫亲和层析净化高效液相色谱法对印度辣椒和新疆辣椒及其辣椒提取物中的黄曲霉毒素(B1、B2、G1、G2)进行检测及迁移规律分析。结果表明,不同来源的辣椒和辣椒提取物中存在不同程度的黄曲霉毒素B1(0.93~51.53 μg/kg)污染,在辣椒生产过程中,黄曲霉毒素部分迁移到辣椒油树脂当中,辣椒红中几乎没有。这一结果说明生产过程中黄曲霉毒素污染主要来源于辣椒原料且易迁移到辣椒油树脂中。在生产中要控制产品中黄曲霉毒素的污染,首要的是做到控制好原料。  相似文献   

16.
We conducted a survey of aflatoxin B1, B2, G1, and G2, ochratoxin A, and fumonisin B1, B2, and B3 contamination in various foods on the retail market in Japan in 2004 and 2005. The mycotoxins were analyzed by high-performance liquid chromatography, liquid chromatography-mass spectrometry, or high-performance thin-layer chromatography. Aflatoxins were detected in 10 of 21 peanut butter samples; the highest concentration of aflatoxin B1 was 2.59 microg/kg. Aflatoxin contamination was not found in corn products, corn, peanuts, buckwheat flour, dried buckwheat noodles, rice, or sesame oil. Ochratoxin A was detected in oatmeal, wheat flour, rye, buckwheat flour, green coffee beans, roasted coffee beans, raisins, beer, and wine but not in rice or corn products. Ochratoxin A concentrations in contaminated samples were below 0.8 microg/kg. Fumonisins were detected in popcorn, frozen corn, corn flakes, and corn grits. The highest concentrations of fumonisins B1, B2, and B3 in these samples were 354.0, 94.0, and 64.0 microg/kg, respectively.  相似文献   

17.
A survey was carried out to detect aflatoxins and isolate aflatoxigenic moulds contaminating fresh and processed meat products. The fungal contamination was examined in 215 samples of fresh and processed meat products and 130 samples of spices used in the meat industry collected from different local companies in Cairo, Egypt. Processed meat products such as beefburger, hot-dog, kubeba, sausage, luncheon meat had the highest count of moulds as compared with fresh and canned meat. Out of 150 samples of meat products and 100 samples of spices, aflatoxin B1 was detected in five samples of beefburger, (8 micrograms/kg), four samples of black pepper (35 micrograms/kg), and four samples of white pepper (22 micrograms/kg). Aflatoxins B1 and B2 were detected in one sample of kubeba (150 micrograms B1/kg and 25 micrograms B2/kg); hot-dog (5 micrograms B1/kg and 2 micrograms B2/kg) sausage (7 micrograms B1/kg and 3 micrograms B2/kg) and luncheon meat (4 micrograms B1/kg and 2 micrograms B2/kg). Also, aflatoxins B1 and G1 were detected in two samples of turmeric (12 micrograms B1/kg and 8 micrograms G1/kg) and coriander (8 micrograms B1/kg and 2 micrograms G1/kg). Aspergillus flavus (24 isolates), and Aspergillus parasiticus (16 isolates) were the predominant aflatoxin-producing moulds isolated from both processed meat products and spices. Aflatoxins were absent in fresh meat, canned meat, salami, beefsteak and minced meat. The contamination of processed meat with aflatoxin was shown to correlate with the addition of spices to fresh meat.  相似文献   

18.
The carry-over of aflatoxins to fig molasses produced by using two different processing techniques from contaminated dried figs (> 1000 ppb of total aflatoxins) were examined by using a HPLC technique. The effects of extraction, bleaching and concentration steps on the reduction of aflatoxin levels were also investigated. The reductions in total aflatoxin levels in fig molasses produced by using the two techniques were detected to be 62 and 38%, respectively. Extraction, bleaching and concentration steps were observed to cause 22% reduction in total aflatoxin levels.  相似文献   

19.
In this study, in order to evaluate the in vitro bioaccessibility of fresh and sun‐dried figs, total antioxidant capacity (TAC), total proanthocyanidin content (TPA) and the major phenolic compounds were determined at different phases of simulated gastrointestinal (GI) tract digestion for Sarilop and Bursa siyahi fig varieties. Four major phenolic compounds (chlorogenic acid, rutin, cyanidin‐3‐glucoside (C3G) and cyanidin‐3‐rutinoside (C3R)) were investigated for GI tract digestion. The results of in vitro GI tract digestion revealed that the dialysed fraction (IN) represented 9–26% and 1–22% of the initial TAC of the whole‐fresh yellow and purple figs, respectively. Moreover, in case of 2,2‐azinobis(3‐ethylbenzothiazoline)‐6‐sulphonic acid (ABTS), TPA and chlorogenic acid contents, drying caused an increase in the IN fraction of yellow figs (38, 140, 50%, respectively). The bioaccessibility of C3G and C3R were quite low for fresh figs (0–5% of the initial values), whereas for dried figs, anthocyanins were not detected at all in the IN fraction.  相似文献   

20.
Aflatoxin contents in 12 types of herbal teas were determined by high performance liquid chromatography (HPLC) with fluorescence detector using immunoaffinity column clean-up. Forty eight samples were collected from four local herbal shops in Manisa, Turkey. Of the 48 samples analyzed, 43 were aflatoxin positive. The highest concentration of aflatoxin (34.18 µg/kg) was determined in a sample of camomile tea. The occurrence of AFB1, B2, G1 and G2 was found in samples at levels of 54, 29, 71 and 46 %, respectively. Aflatoxin B1, B2, G1 and G2 contamination levels varied from 0 to 14.2, 0 to 12.4, 0 to 13.5 and 0 to 28.7 µg/kg, respectively. Aflatoxin was not detected in five samples consisting of linseed, lime and fennel tea.  相似文献   

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