Rice, a staple food for more than half of the global population, undergoes multiple processing stages-such as harvesting, dehulling, milling, and polishing-before it reaches consumers. However, these processes not only alter the physical and nutritional characteristics of rice but may also affect the distribution and concentration of contaminants, thereby posing potential safety and quality risks. In this study, a total of 231 unhusked rice samples were collected from three provinces(Jiangsu, Anhui, and Fujian)in China between 2016 and 2018, along with 11 white rice samples purchased from supermarkets in 2018, and analyzed for the presence of ustiloxin A and D. After dehulling, 31.6% and 5.6% of the brown rice samples were found to be contaminated with ustiloxin A and D, respectively, while neither toxin was detected in the 11 white rice samples obtained from the market. The occurrence of ustiloxin A and D was higher in middle-late rice ecotypes than in the early rice ecotype, with the highest frequency observed in japonica-type rice. Geographically, Jiangsu Province had the highest incidence of ustiloxin A, whereas Anhui Province showed the highest occurrence of ustiloxin D. Importantly, the concentrations of both ustiloxins were higher in unhusked rice than in brown rice and white rice, underscoring that processing can significantly reduce, though not completely eliminate, contamination risks. These findings highlight the importance of continuous monitoring and further investigation into the transfer dynamics of contaminants during rice processing to ensure the safety of the final product.

Rice plays an important role in the daily diet in China and therefore its quality and safety have been of great concern. However, few systematic studies have investigated Fusarium community and toxins in rice grains. Here, we collected 1381 rice samples from Jiangsu Province in eastern China and found a higher frequency of zearalenone (ZEN), deoxynivalenol (DON), fumonisins (FBs), and beauvericin (BEA). The positive samples were individually contaminated with a minimum of one and a maximum of ten toxins. Fusarium was isolated and identified as the major fungus, which exhibited temporal and geographical distribution. The most prevalent species complexes within this genus were Fusarium incarnatum-equiseti species complex (FIESC), Fusarium fujikuroi species complex (FFSC), and Fusarium sambucinum species complex (FSAMSC). Nevertheless, the amplicon sequence analysis revealed a low relative abundance of Fusarium in the rice panicles, and the fungal community exhibited an irregular change along with the symptom's emergence. In vitro toxigenic profiles of Fusarium strains showed significant complexity and specificity depending on the type and content. FIESC strains were non-pathogenic to wheat heads and weakly pathogenic to maize ears, respectively, accumulating lower amounts of toxins than F. asiaticum and F. fujikuroi. There was no significant variation in the ability to cause panicle blight in rice among the various species tested. Our study provides detailed information about the contamination of Fusarium toxins and community in rice after harvest. This information is valuable for understanding the relationship between Fusarium and rice and for developing effective control strategies.

Herbal medicines are widely used for clinical purposes worldwide. These herbs are susceptible to phytopathogenic fungal invasion during the culturing, harvesting, storage, and processing stages. The threat of fungal and mycotoxin contamination requires the evaluation of the health risks associated with these herbal medicines. In this study, we collected 138 samples of 23 commonly used herbs from 20 regions in China, from which we isolated a total of 200 phytopathogenic fungi. Through morphological observation and ITS sequencing, 173 fungal isolates were identified and classified into 24 genera, of which the predominant genera were Fusarium (27.74%) and Alternaria (20.81%), followed by Epicoccum (11.56%), Nigrospora (7.51%), and Trichocladium (6.84%). Quantitative analysis of the abundance of both Fusarium and Alternaria in herbal medicines via RT-qPCR revealed that the most abundant fungi were found on the herb Taraxacum mongolicum, reaching 300,000 copies/μL for Fusarium and 700 copies/μL for Alternaria. The in vitro mycotoxin productivities of the isolated Fusarium and Alternaria strains were evaluated by using liquid chromatography–tandem mass spectrometry (LC-MS/MS), and it was found that the Fusarium species mainly produced the acetyl forms of deoxynivalenol, while Alternaria species mainly produced altertoxins. These findings revealed widely distributed fungal contamination in herbal medicines and thus raise concerns for the sake of the quality and safety of herbal medicines.

[目的]分析长三角地区市场小麦、玉米、稻谷、番茄和桃等常见农产品中真菌毒素的污染水平和特征,为农产品安全监管提供科学依据.[方法]于2019年从长三角地区三省一市(江苏、浙江、安徽和上海)的超市、农家和农贸市场等抽样采集农产品720份,包括120份小麦、150份玉米、150份稻谷、150份番茄和150份桃.谷物样品先后经水和含1％(V/V)甲酸的乙腈溶液提取,果蔬样品经含1％(V/V)甲酸的乙腈溶液提取.提取液通过氯化钠和无水硫酸镁盐析后,采用超高效液相色谱串联质谱法准确测定其中40种重要真菌毒素的含量.分别采用卡方检验和单因素方差分析对农产品中真菌毒素的检出率和含量进行比较,采用Spearman相关对农产品中真菌毒素的含量与产地温、湿度的相关性进行分析.[结果]720份农产品中共检测到36种真菌毒素,主要包括黄曲霉毒素、赭曲霉毒素、链格孢霉毒素、伏马毒素、脱氧雪腐镰刀菌烯醇(DON)及其修饰物和玉米赤霉烯酮(ZEN)等,总检出率为75.3％.其中,伏马毒素B1(FB1)检出率最高(49.0％),其次为细交链孢菌酮酸(TeA)(37.5％)、伏马毒素B2(FB2)(35.7％)、腾毒素(Ten)(29.6％)、伏马毒素B3(FB3) (29.3％)、ZEN(22.6％)、DON(21.4％)、3-乙酰基-脱氧雪腐镰刀菌烯醇(3-ADON)(10.7％)、赭曲霉毒素A(OTA)(10.4％),赭曲霉毒素B(OTB)(8.1％)、脱氧雪腐镰刀菌烯醇-3-葡萄糖苷(D3G)(7.2％)、赭曲霉毒素C(OTC)(6.4％)、黄曲霉毒素B2(AFB2)(5.8％)和15-乙酰基-脱氧雪腐镰刀菌烯醇(15-ADON)(5.4％).59.5％的农产品样品受到2种或2种以上真菌毒素污染,同一份样本中被检出毒素数量最多达到23种.根据GB 2761-2017《食品安全国家标准食品中真菌毒素限量》,有1份玉米样本黄曲霉毒素B1(AFB1)超标,1份稻谷样本OTA超标,6份小麦和2份玉米样本ZEN超标,总超标率为1.4％,整体污染水平不高.农产品中真菌毒素的污染水平表现出一定的类型和地区差异.小麦中,Ten、TeA和DON污染最严重;玉米中,伏马毒素污染较普遍;稻谷中则主要为Ten、TeA和伏马毒素;果蔬中伏马毒素、赭曲霉毒素和链格孢毒素等真菌毒素检出较多.从地区来看,浙江省小麦样品中DON和ZEN污染水平最严重,安徽省玉米样品FB1污染浓度较高,而江苏省稻谷样品中DON和ZEN的检出率和浓度水平均显著高于其他地区.相关性分析表明,谷物中Ten、TeA、FB1、DON和ZEN等毒素的含量与产地温、湿度存在一定的相关性,而果蔬中毒素的含量与温、湿度均无相关性.[结论]长三角地区市场农产品被多种真菌毒素污染,总体污染水平相对较低,但单一样品受到多种毒素混合污染的情况较多,应引起一定的重视.

Species belonging to the Fusarium fujikuroi species complex (FFSC) are of vital importance and are a major concern for food quantity and quality worldwide, as they not only cause serious diseases in crops but also produce various mycotoxins. To characterize the population structure and evaluate the risk of poisonous secondary metabolites, a total of 237 candidate strains were isolated from rice, maize, and soybean samples in Jiangsu Province, China. Species identification of the individual strain was accomplished by sequencing the translation elongation factor 1α gene (TEF-1α) and the fumonisin (FB) synthetic gene (FUM1). The distribution of Fusarium species among the different crops was observed. The maize seeds were dominated by F. proliferatum (teleomorph, Gibberella intermedia) and F. verticillioides (teleomorph, G. moniliformis), whereas F. fujikuroi (teleomorph, G. fujikuroi) was the most frequently isolated species from rice and soybean samples. In addition, phylogenetic analyses of these strains were performed, and the results suggested clear groups showing no obvious relationship with the origin source. FFSC species pathogenicity and toxigenicity were studied. All of the species reduced the rice seed germination rate, with no significant differences. F. fujikuroi showed two distinct patterns of influencing the length of rice seedlings, which were correlated with FBs and gibberellic acid synthesis. FBs were mainly produced by F. verticillioides and F. proliferatum. F. proliferatum and F. fujikuroi also produced moniliformin and beauvericin. The toxigenicity of F. andiyazi (teleomorph, G. andiyazi) was extremely low. Further analysis indicated that the sequence variations in TEF-1α and the differences in the expression levels of the toxin synthesis genes were associated with the diversity of secondary metabolites in F. fujikuroi strains. These findings provide insight into the population-level characterization of the FFSC and might be helpful in the development of strategies for the management of diseases and mycotoxins.

目的 建立超高效液相色谱-串联质谱(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)同时检测小麦、玉米、稻谷、番茄和桃等常见农产品中40种真菌毒素含量的分析方法 .方法 谷物样品先后经水和含1%(V/V)甲酸的乙腈溶液提取, 果蔬样品经1%(V/V)甲酸的乙腈溶液提取,氯化钠和无水硫酸镁盐析后, 取上清液氮吹至干, 残渣经5 mmol/L醋酸铵水溶液-乙腈(80:20, V/V)复溶, 过膜后上机测定, 通过基质匹配标准曲线进行定量分析.结果 40种真菌毒素在各自的线性范围内线性关系良好,相关系数(r2)≥0.99, 检出限和定量限分别为 0.2～10.0 μg/kg 和 0.5～20.0 μg/kg.在低、中、高3个添加水平下, 5 种农产品基质中 40 种真菌毒素的平均加标回收率为 71.8%～118.6% 精密度为 1.2%～16.9%(n=5).结论 本方法 操作简单、灵敏度高、实用性强, 适用于小麦、玉米、稻谷、番茄和桃等常见农产品中40种真菌毒素的同时检测分析.

近年来,以脱氧雪腐镰刀菌烯醇等为主的镰刀菌毒素在我国长江中下游等部分小麦主产区污染形势严峻,严重影响我国小麦产品质量安全及小麦产业健康发展.本文分析了我国小麦镰刀菌毒素污染现状,对镰刀菌毒素污染发生的主要影响因素进行了详细评述,以期提高人们对镰刀菌毒素污染的认识,促进我国小麦镰刀菌毒素污染控制与治理.

Pyruvate dehydrogenase kinase (PDK) is a mitochondrial enzyme in a variety of eukaryotes, including the plant pathogen Fusarium graminearum. This enzyme can reduce the oxidation of glucose to acetyl-coA by phosphorylation and selectively inhibits the activity of pyruvate dehydrogenase (PDH), which is a kind of pyruvate dehydrogenase complex (PDC). In this study, we investigated the F. graminearum pyruvate dehydrogenase kinase encoded by FgPDK2, which is a homologue of Neurospora crassa PDK2. The disruption of the FgPDK2 gene led to several phenotypic defects including effects on mycelial growth, conidiation, pigmentation, and pathogenicity. The mutants also showed decreased resistance to osmotic stress and cell membrane/wall-damaging agents. The FgPDK2 deletion mutant exhibited reduced virulence. All of these defects were restored by genetic complementation of the mutant with the complete FgPDK2 gene. Overall, the results demonstrated that FgPDK2 is crucial for the growth of F. graminearum and can be exploited as a potential molecular target for novel fungicides to control Fusarium head blight caused by F. graminearum.

A colloidal gold (ICS) test was developed for rapid detection of zearalenone (ZEN) in wheat samples. The mAb against ZEN was prepared in our laboratory and labelled with colloidal gold as a probe for the ICS test. The conditions were optimized and 30 nm colloidal gold nanoparticles were chosen for optimal performance. Millipore 135 was chosen as the NC membrane for its level of sensitivity. The optimum amount of coated antigen ZEN-OVA and anti-ZEN mAb was 0.5 mg/mL and 8 μg/mL, respectively. The ICS test, which has a detection limit of 15 ng/mL for ZEN, could be completed in 5 min. Analysis of ZEN in 202 wheat samples over three consecutive years revealed that data obtained from the ICS test were in a good agreement with LC-MS/MS data. This result demonstrated that the ICS test could be used as a qualitative tool to screen on-site for ZEN.

以提高溶液中抗黄曲霉毒素B1单克隆抗体纯度为目的,采用来自小鼠腹水、经辛酸-饱和硫酸铵法提取的粗品单抗溶液为原料,通过单因次和响应面优化试验,建立了两步超滤法的纯化工艺.第一次超滤采用200 kD截留分子量的超滤膜.第二次超滤采用50 kD截留分子量的超滤膜,超滤温度25℃、超滤压力0.12 MPa、浓缩倍数6倍.取两步超滤的中间截留液,单抗纯度可达80.5％,而提取率仅下降8.7％.纯化工艺对单抗效价没有影响,基本脱除了溶液中的硫酸铵.该工艺可用于大规模制备高质量的抗AFB1单克隆抗体.

通过分析国际食品法典委员会(Codex Alimentarius Commission,CAC)框架下食品安全风险分析过程中的食品安全风险交流机制,并分析食品安全风险交流的基本特性,明确其基本概念、风险交流形式及基本原则,同时探讨CAC食品安全风险交流的监管工作及风险交流的注意事项,以期从风险交流的主体、参与平台以及国际合作多个角度为我国食品安全监管中风险交流工作提供参考.

镰刀菌毒素是污染我国粮食作物的主要毒素之一.本文针对食品和饲料中的主要污染镰刀菌毒素,就其限量和分析方法标准进行了梳理,比较国内外的差异,为不断补充和完善我国农产品中镰刀菌毒素检测标准体系工作提供参考.

Deoxynivalenol (DON), a notorious mycotoxin mainly found in Fusarium-contaminated crops, causes great loss in livestock farming and severe safety risks to human health. Here we report the isolation of a Gram-negative bacterial strain with effective biodegrading abilities on DON and its derivatives including 3-acetyl-DON and 15-acetyl-DON. The strain was identified as Devosia insulae A16 on the basis of morphological and physiological characteristics and 16S rRNA-based phylogenetic analysis. D. insulae A16 was able to degrade 88% of 20 mg/l DON within 48 h under aerobic conditions at 35 degrees C and neutral pH. The major degradation product of DON and its derivatives was 3-keto-DON by the oxidation of the hydroxyl group at C-3. Both 3-acetyl-DON and 15-acetyl-DON underwent a deacetylation reaction to generate DON prior to the degradation to 3-keto-DON. The results provide the potential use of D. insulae A16 as a biodegradation agent to control DON contamination in cereals.

Zearalenone (ZEN) is a mycotoxin produced mainly by various Fusarium species which occur naturally in many crops worldwide. ZEN causes reproductive disorders and hyperestrogenic syndromes in animals and humans. This study aimed to isolate ZEN-degrading bacteria to develop strategies for detoxifying ZEN contamination in cereal crops. We screened approximately 1000 colonies for degrading ability and found four strains were capable of degrading ZEN. We selected one strain ZDS-1 for further study because it showed the high ZEN-degrading ability. On the basis of morphological, physiological and phylogenetic analysis of its 16SrRNA, gyrA gene sequences, strain ZDS-1 was identified as Bacillus amyloliquefaciens. The optimal conditions for the biodegradation of ZEN by ZDS-1 were temperature; 30 degrees C, pH; 6.0-7.0, and cell concentration; 5 x 10(8) cfu/mL. ZDS-1 could degrade ZEN efficiently with the concentration from 1 mg/L to 100 mg/L. ZDS-1 not only could remove ZEN in the culture medium, but also could degrade ZEN in wheat. The ZEN removal by ZDS-1 was not due to binding or absorption, and during the process of ZEN degradation, no ZEN derivatives of ZEN were produced. These results suggested that Bacillus amyloliquefaciens ZDS-1 would be explored further for its ability to degrade ZEN in field trials. (c) 2016 Elsevier Ltd. All rights reserved.

近年来,小麦赤霉病在我国小麦产区高频率流行,尤其在长江中下游、淮河流域以及黄淮南部,导致小麦中镰刀菌毒素严重污染,不仅影响小麦产量,还危害人畜健康.镰刀菌毒素包括脱氧雪腐镰刀菌烯醇(DON,又称呕吐毒素)、玉米赤霉烯酮(ZEN)、雪腐镰刀菌烯醇(NIV)以及伏马毒素(FB)等,可以引起动物消化、神经、免疫以及生殖系统异常,有的还具有致癌作用.本文对我国小麦镰刀菌毒素的发生情况与影响因素进行了分析,同时对镰刀菌毒素的风险评估与防控研究的迫切性进行了探讨,以期提高人们对小麦镰刀菌毒素污染的认识,保障我国小麦产业的健康发展.

研究含水量分别为11．5％、12．8％、15．7％的小麦在4℃冷库、25℃恒温室、常温库、地下仓库4种环境下储藏0～90 d镰刀菌毒素DON、NIV含量的变化情况，并对不同储存环境下小麦含水量变化情况进行分析。结果表明：90 d内，3种含水量的小麦在4℃冷库和25℃恒温室条件下，DON、NIV毒素均未发生显著变化。储存在常温库和地下仓库2种不可控环境下的3种含水量小麦在60 d后DON毒素含量降低，NIV毒素含量未发生显著变化。

The strain A16, capable of degrading deoxynivalenol was isolated from a wheat field and identified preliminarily as Devosia sp. Here, we present the genome sequence of the Devosia sp. A16, which has a size of 5,032,994 bp, with 4913 coding sequences (CDSs). The annotated full genome sequence of the Devosia sp. A16 strain might shed light on the function of its degradation.

菌株AF0907是从土壤中分离到的1株对小麦赤霉病菌具有显著拮抗作用的枯草芽孢杆菌,该菌株不仅对小麦赤霉病菌具有很好的拮抗活性,对其他多种植物病原菌都具有很好的拮抗效果.为了明确菌株AF0907对赤霉病菌的抑菌机理,本研究首先使用平板对持法对拮抗物质进行定位,结果表明该菌分泌的拮抗物质主要位于细胞上清液中.采用不同饱和度的硫酸铵沉淀细胞上清液,确定了60％的硫酸铵饱和度是沉淀该拮抗物质的最佳条件;分别研究了温度、pH值、蛋白酶K、氯仿对该拮抗物质活性的影响,结果表明该拮抗物质在低温下比较稳定,在60℃以上的高温下,活性迅速降低;在酸性或碱性条件下不稳定;该拮抗物质分别加入蛋白酶K和氯仿作用后拮抗活性分别下降了60.68％、80.07％,因此,初步判断该拮抗物质为蛋白质.利用DEAE-52离子交换柱层析法分离纯化了该拮抗蛋白并进行了SDS-PAGE电泳,结果显示该拮抗蛋白的分子量为48 kDa;利用PPSQ-31A蛋白自动测序仪测定拮抗蛋白N-末端15个氨基酸序列为:His-Glu-Phe-Pro-Thr-Tyr-Lys-His-Met-Tyr-Gln-Val Met-His-Leu.