Occurrence of patulin in conventional and organic fruit products in Italy and subsequent exposure assessment.

The occurrence of patulin was investigated in 100 conventional and 69 organic fruity foodstuffs samples commercially available in Italy by using an HPLC method with a limit of quantification of 0.5 microg kg(-1). Patulin was detected in 26 (26%) conventional and 31 (45%) organic products with a significantly higher (p<0.01) mean concentration in the organic products (4.78 vs. 1.15 microg kg(-1)). Mean patulin concentrations in conventional apple juices, pear juices, other juices and fruits purees were 3.14, 0.22, 0.19, 0.11 microg kg(-1), respectively, and 7.11, 11.46, 2.10, 0.18 microg kg(-1) in the relevant organic products. Four samples of juices (one conventional and two organic apple, and one organic pear) contained patulin at concentrations above the limit of 50 microg kg(-1), four at concentrations between 10 and 25 microg kg(-1), and the remaining ones below 10 microg kg(-1). Patulin was detected (<1 microg kg(-1)) in only three of the 23 fruity baby food samples tested (homogenized fruits, 11 conventional and 12 organic). Based on the available data on Italian intakes of fruit juices, the estimated daily intakes of patulin, were 0.38 and 1.57 ng kg(-1) body weight (bw) from conventional and organic products, respectively. Estimated daily intakes of patulin for children were higher, 3.41 ng kg(-1) bw from conventional and 14.17 ng kg(-1) bw from organic products, but largely below the provisional maximum tolerable daily intake (PMTDI) of 400 ng kg(-1) bw. Patulin was also found in two samples of organic apple vinegar (<5 microg kg(-1)) and in fresh apples with rotten spots (12 out of 24 samples) with maximum levels at 16,402 and 44,572 microg kg(-1) for conventional and organic apples, respectively.     

水果及其制品中展青霉素的研究进展

展青霉素是一种毒性极强的真菌毒素,广泛存在于水果及其制品中,严重危害人类健康。本文综述了近年来水果及其制品中的展青霉素的研究进展,介绍了展青霉素的相关性质,分析了展青霉素的生物合成及降解机制,并论述了展青霉素的检测方法及相关微生物对展青霉素的脱除效果。      

Patulin biodegradation by marine yeast Kodameae ohmeri

Patulin contamination of fruit- and vegetable-based products had become a major challenge for the food industry. Biological methods of patulin control can play an important role due to their safety and high efficiency. In this study, a strain of marine yeast with high patulin degradation ability was screened. The yeast was identified as Kodameae ohmeri by the BioLog identification system and partial 26S rRNA gene sequencing. The degradation products of patulin were identified as (E)- and (Z)-ascladiol through HPLC and LC-TOF/MS. High patulin tolerance at 100 μg ml^–1 and a high degradation rate at 35°C at a pH between 3 and 6 indicates the potential application of K. ohmeri for patulin detoxification of apple-derived products.     

Co-occurrence of patulin and citrinin in Portuguese apples with rotten spots

Patulin and citrinin are mycotoxins produced by certain fungi mainly belonging to Penicillium and Aspergillus and may be detected in mouldy fruits and fruit products. The data presented here refer to the simultaneous occurrence of patulin and citrinin in 351 samples of seven different varieties of apples with small rotten areas (Casanova, Golden Delicious, Red Delicious, Reineta, Richared, Rome Beauty, Starking). A rapid multidetection thin layer chromatography (TLC) method was used. The minimum detectable concentrations of patulin and citrinin were 120-130 and 15-20 μg kg^-1 respectively. The percentage contamination with patulin only was higher (68.6%) than that with citrinin only (3.9%). Patulin and citrinin (19.6%) were also detected simultaneously. The highest mean patulin content was 80.50 mg kg^-1 for the Richared variety, but the mean level of citrinin was lower. The lowest mean contaminations of patulin were found in Rome Beauty, Red Delicious and Reineta, ranging from 3.06 to 5.37 mg kg^-1. All analysed apples varieties had low citrinin contamination, ranging from 0.32 to 0.92 mg kg^-1. These findings indicate that there may be a risk of human exposure to patulin through the consumption of juices and jams manufactured with apples with small rotten areas.     

食品中展青霉素的研究进展

展青霉素是由曲霉菌和青霉菌等真菌产生的次级代谢产物, 是广泛存在于水果(特别是霉变水果)、水果制品(果汁、果酱、果脯等)及谷物等食品中的天然污染物, 可以通过食物摄取的方法进入机体。展青霉素不仅具有免疫毒性和致畸性, 而且对人体多种器官都有毒害作用。展青霉素污染的食品(尤其是水果及水果制品)不仅会对人类健康造成严重的威胁, 而且会严重危害我国经济和食品加工业的发展。为了探讨食品中展青霉素的研究进展, 本文主要从展青霉素的基本性质、毒性与危害、检测方法和脱除方法等部分进行论述, 以期为展青霉素的毒性研究提供的理论参考。     

棒曲霉素的生物合成、调控机制及其控制技术研究进展

棒曲霉素(patulin)是一种真菌的次生代谢产物。它对人和动物具有急性和慢性毒性,是污染水果及其加工制品的最重要的真菌毒素之一。食品中的棒曲霉素污染是一个全球性的问题,受到世界各国的关注,100多个国家和地区对果汁等水果加工制品中棒曲霉素的最高含量做了限定。棒曲霉素主要由青霉属、曲霉属、拟青霉属和丝衣霉属中的部分真菌产生。其中,扩展青霉(Penicillium expansum)是生产上棒曲霉素最重要的产生菌,因此成为研究棒曲霉素生物合成和调控机制的模式材料。近年来,随着食品安全问题越来越被人们重视,水果及其加工制品的真菌毒素污染问题也受到越来越多的关注,相关领域的研究逐渐成为热点。本文主要阐述了棒曲霉素的生物合成途径、分子基础、内外源调控因子和分子调控机制以及控制技术等方面的最新研究进展,并展望了棒曲霉素相关研究未来的重点。     

食品中展青霉素脱除方法研究进展

展青霉素由多种真菌产生,毒性极强,广泛存在于水果及其制品中,并通过食物链在人体富集,严重危害人类健康。本文综述了近年来物理、化学和生物方法去除和降解食品中展青霉素的研究进展,并对降解产物及其安全性进行了探讨。     

Detection of patulin in apple juices marketed in the Tohoku district, Japan

Patulin is a mycotoxin mainly produced by Penicillium and Aspergillus. We investigated the incidence of patulin contamination in 179 samples of apple juice and 9 samples of mixed juice (containing apple juice concentrate as an ingredient) commercially available in the Tohoku district of Japan. Patulin was detected in 3 of 143 samples containing domestic fruits and in 6 of 45 samples containing imported products and products produced in Japan using imported apple juice concentrate. Patulin analyses were carried out using high-pressure liquid chromatography with a detection limit of 4 microg/liter. The patulin content of contaminated domestic samples (three samples with concentrations ranging from 6 to 10 microg/liter), imported samples (one sample with a concentration of 15 microg/liter), and domestic samples produced containing imported concentrate (five samples with concentrations ranging from 6 to 9 microg/liter) was lower than the maximum limit of 50 microg/liter currently adopted by many countries, including Japan.     

Potential of two Metschnikowia pulcherrima (yeast) strains for in vitro biodegradation of patulin

Patulin contamination of apple and other fruit-based foods and beverages is an important food safety issue, as consumption of these commodities throughout the world is great. Studies are therefore necessary to reduce patulin levels to acceptable limits or undetectable levels to minimize toxicity. This study was undertaken to investigate the efficacy of two Metschnikowia pulcherrima strains (MACH1 and GS9) on biodegradation of patulin under in vitro conditions. These yeast strains were tested for their abilities to degrade patulin in liquid medium amended with 5, 7.5, 10, and 15 μg/ml patulin and a yeast cell concentration of 1 × 10(8) cells per ml at 25°C. Of the two strains tested, MACH1 completely (100%) reduced patulin levels within 48 h, and GS9 within 72 h, at all concentrations of patulin. MACH1 effectively degraded the patulin within 24 h by 83 to 87.4%, and GS9 by 73 to 75.6% at 48 h, regardless of concentration. Patulin was not detected in yeast cell walls. This indicates that yeast cell walls did not absorb patulin, and that they completely degraded the toxin. Patulin had no influence on yeast cell concentration during growth. Therefore, these yeast strains could potentially be used for the reduction of patulin in naturally contaminated fruit juices. To our knowledge, this is the first report regarding the potential of M. pulcherrima strains for patulin biodegradation.     

Long-term survey of patulin in apple juice concentrates produced in Turkey.

A liquid chromatographic method described by us elsewhere was evaluated for a long-term survey of patulin in apple juice concentrates. Patulin was separated on a reversed phase C18 LC column with water-acetonitrile (99:1) as the mobile phase and quantitated with a photodiode array (PDA) detector. Relatively low amounts of patulin (< 5 micrograms/l for single strength juice at 11.2 degrees Bx) were detected in apple juice concentrates and confirmed by PDA detector, comparing the corresponding UV spectra with that of patulin standard. Four hundred and eighty two apple juice concentrates produced through 1996-99 were analysed for their patulin contents. Year-to-year variations in patulin levels of apple juice concentrates were found out to be statistically significant. Patulin contamination levels of apple juice concentrates tended to decrease through the years and averaged 63, 43, 19 and 31 micrograms/l in 1996, 1997, 1998 and 1999, respectively. Percentages of concentrates exceeding the maximum permitted concentration of 50 micrograms/l were 52%, 34%, 8% and 8% for 1996, 1997, 1998 and 1999, respectively.     

苹果及其制品中展青霉素生物防治研究进展

展青霉素是一种由真菌产生的次级代谢产物,普遍存在于腐烂的蔬菜、水果中,特别是苹果及其制品中。展青霉素具有广泛的生理及细胞毒性,对人的健康和安全构成了严重的威胁。近年来,采用生物防治方法控制苹果及其制品中展青霉素的污染已成为国际学术界研究的热点。本文综述生物防治方法控制苹果及其制品中展青霉素的研究进展,并论述展青霉素的生物防治机制,为推动生物防治方法在展青霉素控制方面的应用提供参考。     

Incidence of patulin in apple juices marketed in Turkey.

The purpose of this study was to investigate the patulin contamination of apple juices consumed by the Turkish population. Patulin was detected using high-performance liquid chromatography (HPLC) with a UV detector at 280 nm, and the identification of patulin was further confirmed by thin-layer chromatography (TLC). Using HPLC, the recoveries were 79.9 +/- 6.7% and 83.7 +/- 4.6%, and the coefficients of variation were 8.4 and 5.5% for apple juices spiked with the known amounts of patulin (60 and 120 microg/liter. respectively). The minimum patulin level detected was 5 ng in a standard solution and 5 microg/liter in apple juices. The TLC method was used only to confirm patulin levels higher than 20 microg/liter (100 ng/spot) in apple juices. The total number of samples was 45. Patulin was present in detectable levels in 60% of apple juices at concentrations ranging from 19.1 to 732.8 microg/liter. Forty-four percent of the apple juice samples had patulin contamination levels higher than 50 microg/ liter, which is the allowable upper limit in Turkey.     

Factors affecting patulin production by Penicillium expansum

Patulin, a mycotoxin produced by Penicillium spp. during fruit spoilage, is a major concern with regard to human health because exposure can result in severe acute and chronic toxicity, including carcinogenic, mutagenic, and teratogenic effects. In this study, we investigated the effects of Penicillium expansum isolate, apple cultivar, storage temperature and time, and pH on the production of patulin. Patulin was analyzed by a previously developed micellar electrokinetic capillary electrophoresis method. P. expansum isolates originating from across Ontario produced widely differing levels of patulin, ranging from 0 to >6 mg/g by dry mycelial weight. The highest patulin levels were those for isolates displaying aggressive growth (characterized by rapidly increasing acidity) accompanied by profuse mycelial development. Distinct patterns in fungal growth rates and patulin production were evident among isolates grown in McIntosh, Empire, and Mutsu ciders. Extensive fungal growth and higher patulin levels (538 to 1,822 microg/ml on day 14) in apple ciders were associated with incubation at room temperature (25 degrees C), although potentially toxic patulin levels (75 to 396 microg/ml on day 24) were also found in refrigerated ciders (4 degrees C) inoculated with P. expansum.     

Cold and ambient deck storage prior to processing as a critical control point for patulin accumulation

Patulin, a mycotoxin produced primarily by Penicillium expansum, is currently of great concern because of its undesirable effects in human health. It has been proven that patulin can damage organs and tissues in animals and some studies revealed carcinogenic and teratogenic effects. Patulin is found mainly in low quality apples diverted to production of apple by-products. Apples from cold storage or recently harvested (usually ground harvested or low quality apples) are stored under ambient conditions (deck storage) until they are processed. The present assay studies the consequences of this type of storage in development of lesions and patulin accumulation. The assayed factors were the size of lesions when apples were taken out from cold storage, time the apples stayed at room temperature after cold storage (as a simulation of deck storage) and intraspecific differences between 2 isolates of P. expansum. A sublot of P. expansum inoculated apples was cold stored until lesions achieved concrete sizes. Then, apples were either transferred to a 20 degrees C storage room for 0 to 5 days or were analysed for patulin immediately. The rest of the apples were directly stored at 20 degrees C. Each treatment had three replicates. Increase of lesion size with time at 20 degrees C depended on initial lesion size after cold storage. Bigger lesions were always achieved in apples with bigger initial lesion size. Initial lesion size and time at 20 degrees C significantly influenced patulin accumulation. No significant amounts of patulin were found in apples with lesions up to 2 cm after cold storage. Patulin amounts significantly increased on the 2nd day at 20 degrees C day and remained constant until the 5th day. Patulin accumulation tended to be higher when initial lesions were bigger. The assay showed the influence of apple quality (measured as overall lesion size) after cold storage on patulin accumulation during deck storage, as well as the importance of duration of deck storage. Quality of apples entering the processing plant should be assessed in order to program deck storage and minimise patulin accumulation. Predictive models of patulin accumulation as a function of time at room temperature and apple quality should be a useful tool to elaborators.     

A quantification and confirmation method of patulin in apple juice by GC/MS

A sensitive and selective method for quantification and confirmation of patulin in apple juice by GC/MS was developed. By this method, patulin was precisely determined and confirmed down to the level of 1 and 5 microg/kg in samples, respectively. Patulin was extracted with ethyl acetate from a sample and then hexane was added to the concentrated extract solution. Significant amounts of insoluble impurities were filtered off, followed by further clean-up by solid-phase extraction with combined silica gel and Florisil cartridges. The filtration step in a low-polarity condition was very effective to remove the impurities in the sample extract solution. The eluate from the cartridges was evaporated to dryness under reduced pressure and patulin was determined and confirmed by GC/MS after derivatization with 2.5% N,O-bis(trimethylsilyl)trifluoroacetamide ethyl acetate solution. Patulin was determined in the selected ion monitoring mode (m/z 226) and confirmed in the SCAN mode (m/z 40-340). The recovery from apple juice spiked with 10-500 microg/kg ranged from 93.4 to 100%. The limits of detection and quantification were 0.1 (S/N = 3) and 1 microg/kg (S/N = 30) of patulin in samples, respectively. Levels down to 5 microg/kg of patulin in sample were readily confirmed.     

展青霉素检测方法的研究进展

展青霉素是由部分曲霉、青霉产生的有毒的代谢产物,主要污染水果及其制品。对目前常见的展青霉素的检测方法薄层色谱法、气-质相联机色谱法、液相色谱法、免疫学检测方法进行了综述,讨论了4种方法的优缺点,指出免疫检测方法是检测展青霉素的发展方向。     

Patulin distribution in Fuji and Golden apples contaminated with Penicillium expansum

This work assesses the extent of patulin contamination in Penicillium expansum-infected apples stored at room temperature for short periods of time and its relationship with apple variety (Golden or Fuji), degree of ripeness and size of lesions. Inoculated apples were incubated at 20°C. Patulin was determined in both sound and decayed tissue from cylindrical samples taken around the lesions and cut into 0.5-cm thick sections. Higher accumulation of patulin occurred in Golden apples, with less ripened apples showing higher concentrations. Total accumulated patulin was similar or higher in 4-cm compared to 2-cm lesioned apples, although a decrease in patulin concentration was observed in older lesion sections. Patulin accumulation occurred over a short period of time at room temperature, thus the stand-by period before processing should be minimised. Of total patulin, 2-6% migrated to the surrounding sound tissue, thus trimming tissue around the rotten part may be a good preventive practice for apple derivative production.     

食品中展青霉素的产生机制及污染防控策略

展青霉素是由真菌产生的一种聚酮类次级代谢产物,是污染水果及其加工制品的最重要的真菌毒素之一。食品中污染的展青霉素主要由扩展青霉(Penicillium expansum)产生。P.expansum是常见大宗和特色果品的主要采后病原菌,其在引起果实腐烂的同时产生大量的展青霉素,伴随鲜食流通和加工过程进入食物链,危害消费者的健康。展青霉素可侵害人和动物的多个器官,引起急性和慢性症状。由展青霉素污染引起的食品安全问题越来越得到重视,展青霉素的相关研究逐渐成为热点。对展青霉素的产生和调控机制研究进行了系统的总结,介绍了展青霉素生物合成基因簇的组成,生物合成途径中不同步骤的催化酶,展青霉素生物合成和中间产物转运的分子路径;从合成途径特异性调控因子,光、pH值、碳源、硫源等环境信号-全局性调控因子,以及参与组蛋白甲基化和乙酰化修饰的表观遗传因子等不同层次归纳了展青霉素生物合成的复杂调控网络。从源头防控和直接脱除2个方面阐述了食品中展青霉素污染的防控策略,分别概述了基于物理、化学和生物原理的主要防控技术,并讨论了不同防控策略的优缺点。最后,讨论了展青霉素产生机制研究与污染防控技术研发的关系,并指出绿...     

Contamination of food products with patulin

Based on the method for patulin determination designed by the authors the rate and level of contamination of fruit, vegetables and foods manufactured from them (juices, purees, jams) with this mycotoxin were studied. Patulin was found in 8 out of 160 samples of fruit and vegetables, the highest concentration of patulin was identified in the berries of sea buckthorn (up to 54 000 micrograms/kg). Patulin was found in 28 out of 185 samples of foods manufactured from fruit. The concentration of patulin in juices did not exceed the allowable concentrations on the average. Patulin was largely identified in apple, sea buckthorn and plum juices.     

Stability of patulin at ph 6.0-8.0 and 25 degrees c.

Patulin was tested for stability at pH values of 6.0, 6.5, 7.0, 7.5, and 8.0, using S?rensen's phosphate buffer at 25 degrees C. Patulin was determined by high-performance liquid chromatography. When the percentage of patulin remaining was plotted versus reaction time, apparent first-order reaction plots were obtained. Reaction rate constants for disappearance of patulin ranged from 1.1 x 10(-2) h at pH 8.0-5.3 x 10(-4) h at pH 6.0. Values for half-life were calculated and ranged from 64 h at pH 8.0 to 1310 h at pH 6.0.