镰刀菌单端孢霉烯族毒素的生物合成及分子调控研究进展

单端孢霉烯族毒素主要是由镰刀菌属等丝状真菌产生的一类有毒的次级代谢产物,对人类和动物的健康造 成威胁。本文对镰刀菌单端孢霉烯族毒素的生物合成基因、生物合成途径及编码酶、分子调控分别进行了阐释, 其中生物合成至少涉及到3 个基因家族,分别为Tri5基因簇、Tri1～Tri16基因簇和Tri101基因簇,包括编码单端孢霉 二烯合酶的Tri5,编码P450单加氧酶的Tri4、Tri11和Tri13,编码转录调控因子的Tri6和Tri10,编码乙酰基转移酶的 Tri7、Tri3、Tri16和Tri101,编码酯酶的Tri8,编码羟化酶的Tri1,编码毒素输出泵的Tri12。生物合成起始于反式法 尼基焦磷酸环化形成单端孢霉二烯,再经过一系列的加氧、异构化、环化和酯化反应,最终形成不同结构的毒素, 毒素形成的差异主要是由代谢途径和基因差异决定的。生物合成除了受TRI6和TRI10特异的转录调控因子调控之 外,还受到与外界环境相关的全局性调控因子Pac和VeA的调控。本文旨在为食品、饲料等农产品的毒素防控、毒 素脱除提供理论依据。     

真菌毒素快速检测技术

<正>真菌毒素,又称霉菌毒素,是真菌在食品或饲料里生长所产生的代谢产物,对人类和动物都有害。真菌毒素可通过饮食进入人或动物体内,引起人或动物的急性或慢性中毒,进而损害机体,造成肝脏、肾脏及神经组织等的伤害。真菌毒素主要包括黄曲霉毒素、呕吐毒素、玉米赤霉烯酮赭曲霉毒素等。1960年,英国10万多只火鸡因食用被黄曲霉毒素污染的饲料而死亡,此事件发生后,真菌毒素才逐渐引起人们的重视。受全球气候变暖、干旱等因素的影响,食用和饲用农产品受真菌毒素污染的现象日趋严重,世界各地对于真菌毒     

禾谷镰刀菌脱氧雪腐镰刀菌烯醇生物合成及其分子调控研究进展

禾谷镰刀菌是感染小麦、玉米等主要粮食作物的一种重要的病原真菌，在引发严重小麦赤霉病害的同时，可分泌产生脱氧雪腐镰刀菌烯醇（DON），污染食品后不易被清除，严重威胁人和动物的健康。禾谷镰刀菌产DON的生物合成路径及分子调控机制一直是国内外的研究热点、焦点和难点，也是防控DON的基础。本文综述了禾谷镰刀菌DON生物合成过程中涉及产毒基因簇TRI的各个基因、编码蛋白及其生物学功能，以及目前对禾谷镰刀菌中对呕吐毒素生物合成调控机制的研究进展。这些基础信息将直接为安全控制主要粮食及其制品中真菌毒素污染提供有价值的参考资料。     

改性蒙脱石消减黄曲霉毒素B1的研究进展

真菌毒素污染严重威胁食品、农产品和饲料产业高质量发展和人民生命健康.黄曲霉毒素B1是污染广,毒性最大的一种真菌毒素,具有强致癌性和致畸性.天然蒙脱石可通过离子-偶极子、羰基氧配位及静电引力等方式与黄曲霉毒素B1结合,因此有一定的吸附脱除作用.但天然蒙脱石在吸附黄曲霉毒素的同时可能会影响基质中的矿物质、维生素与其他营养组...     

基于先进材料的纸基传感器在多毒素联合检测中的应用

农产品、食品和饲料等常因霉菌侵染而被多种真菌毒素污染，研发高通量真菌毒素快速检测产品是热点研究领域之一。目前主流的真菌毒素快检产品中，传统纸基传感器大多以胶体金作为信号标记物用于单一毒素检测，获得信息相对有限。多毒素纸基传感器常常偶联多种真菌毒素抗原，成本更低，耗时更短，然而检测灵敏度因测试样液量变化而受到影响。近年来，在真菌毒素快检领域引入贵金属纳米粒子、量子点、碳纳米材料、上转换粒子、镧系金属纳米粒子等先进材料，可以改善传感器的检测性能。笔者总结了多毒素纸基传感器的检测原理和组成，综述近年来文献报道中基于先进材料的纸基传感器同时检测多种真菌毒素的研究与应用，分析多毒素纸基传感器未来的研究趋势，以期为多种真菌毒素快速高通量检测相关研究提供参考。     

基于基因测序鱼露发酵橘青霉YL-1鉴定及安全性评价

目的：为弥补传统方法在检测菌株产毒素上的不足,用基因组方法分析橘青霉YL-1（Penicillium citrinum YL-1,P. citrinum YL-1）物质生物合成途径及关键基因,以此评价P. citrinum YL-1在鱼露发酵生产过程中的安全性。方法：应用ITS基因测序鉴定菌株,利用Illumina平台Hiseq测序技术对菌株YL-1进行基因组survey测序,通过生物信息分析产青霉毒素、黄曲霉毒素及典型丝状真菌毒素的非核糖体多肽合成代谢、聚合酮酶代谢、聚合酮酶-非核糖体多肽联合代谢、萜类化合物代谢和氨基酸相关代谢途径及基因,考察菌株YL-1产真菌毒素能力,判断其是否存在产真菌毒素的潜在危害。结果：ITS鉴定菌株YL-1与P. citrinum同源性99%,survey测序结果表明P. citrinum YL-1全基因组大小为31.92?Mb,GC为46.27%。利用Maker2基因预测技术得到预测基因11?980?个。其中,被KOG注释基因5?417?个,被COG注释基因4?946?个;比对KEGG数据库被注释通路323?条,注释基因3?525?个。代谢分析表明,注释到可能产真菌毒素相关的代谢途径有5?条,仅注释到1?种产黄曲霉毒素代谢途径的同源基因Afld及其他5?种相关基因,但并未注释到其完整代谢途径。结论：ITS基因测序鉴定菌株YL-1为P. citrinum,P. citrinum YL-1基因注释存在1 种产黄曲霉毒素的同源基因及其他5?种相关基因,虽不存在完整代谢链,但P. citrinum YL-1运用于鱼露及相关产品的发酵安全性仍值得进一步考察。     

粮油加工副产物中真菌毒素消减技术研究进展

真菌毒素是一些真菌在生长繁殖过程中产生的有毒有害代谢物，其对粮油加工产业、畜牧业和食品工业造成经济损失的同时亦会威胁人类健康。粮油加工副产物中真菌毒素的污染率相对较高，这些污染的副产物用于畜牧业生产，会严重影响畜禽生产性能。对畜禽危害严重的真菌毒素主要有：黄曲霉毒素（aflatoxin，AF）、脱氧雪腐镰刀菌烯醇（又称呕吐毒素，Deoxynivalenol ，DON）、赭曲霉毒素（ochratoxin，OTA）、玉米赤霉烯酮（zenralenone，ZEN）、T-2毒素（属于单端孢霉烯族毒素）、伏马毒素（fumonisin，FB）等。受真菌毒素污染的饲料和谷物颜色、气味及营养成分会发生变化，导致适口性变差，营养价值降低，还会造成畜禽生长缓慢、免疫力降低、生殖障碍甚至死亡。我国《食品卫生标准（GB2761-2017）》对粮油食品中主要真菌毒素的限量有相应的控制标准。《饲料卫生标准（GB13078-2017）》也明确规定粮油加工副产物用作饲料时其中主要六种真菌毒素的限量标准。目前常用的真菌毒素脱毒方法有物理脱毒法、化学脱毒法、脱霉剂脱毒法等。在处理霉变畜禽饲料时，前两种方法都有一定的缺陷，通常采用添加真菌毒素脱霉剂来降低其对畜禽的危害。本文阐述了饲料中常用脱霉剂吸附剂和降解菌/酶以及脱霉剂体外和体内评估方法，总结了现有吸附剂和降解菌/酶对控制粮油副产物中真菌毒素的作用效果以及使用中存在的问题，并对真菌毒素消减技术的发展方向进行了展望，以期为解决资源浪费问题，促进粮油加工副产物的高效利用提供一定的参考价值。     

有关“黄曲霉毒素”

一、了解黄曲霉毒素的重要性 自从1960年英国十万只火鸡因黄曲霉毒素中毒死亡事件之后,许多国家对黄曲霉毒素进行研究,特别是近十年对黄曲霉毒素的污染、毒性、代谢、作用机理、生物合成及防霉去毒等方面都进行了大量的研究;并对粮食、食品和饲料中黄曲霉毒素含量作了特定的限制。我国有关部门也极为重视,多次修改制定在粮食、食品和饲料中黄曲霉毒素最大可允许限量     

农产品中真菌毒素的微生物脱除研究进展

农产品中的真菌毒素污染,不仅造成农业产业的巨大经济损失,而且直接危害人类的身体健康。虽然物理法与化学法在早期真菌毒素脱除中发挥了一定的作用,但是通过微生物脱除真菌毒素,作为一种安全、高效、经济的方式越来越受到认可。本文综述微生物对农产品中常见真菌毒素的两种主要脱除方式（吸附和降解）,前者主要包括乳酸菌及酵母,以菌体吸附的方式,对黄曲霉毒素、玉米赤霉烯酮、脱氧雪腐镰刀菌烯醇、赭曲霉毒素、T2毒素、伏马毒素B1、展青霉素等真菌毒素的脱除效果较好;后者则集中体现在红球菌、芽孢杆菌、假单胞菌及酵母,依靠微生物代谢的方式对上述毒素进行降解。通过对研究报道的归纳和总结,概述了常见的真菌毒素脱除菌株及其代谢机制的研究进展,以及其在农产品真菌毒素脱毒方面的创新性变革。     

曲霉属真菌毒素的毒性研究进展

曲霉属真菌产生的真菌毒素是最早被发现并被重视的一类真菌毒素,多污染食品、饲料和中药,其种类繁多,且对人体的危害性巨大。近年来,国内外对此类真菌毒素的毒性研究愈加关注,本综述总结了曲霉菌属真菌产生的_13种主要真菌毒素(黄曲霉毒素B_1、黄曲霉毒素B_2、黄曲霉毒素G_1、黄曲霉毒素G_2、黄曲霉毒素M_1、黄曲霉毒素M_2、黄曲霉毒素P_1、赭曲霉毒素A、赭曲霉毒素B、赭曲霉毒素C、赭曲霉毒素α、杂色曲霉素和O-甲基-杂色曲霉素)近40年来体内、体外毒性研究资料,对其各项毒性进行归纳,主要涵盖急性毒性、慢性毒性的致癌性、生长生殖毒性、致突变和基因毒性、免疫毒性、神经毒性、细胞毒性及血液毒性。同时对黄曲霉毒素B_1、赭曲霉毒素A及其他常见毒素间的协同毒性也进行了概述。由于各国对食品药品的安全性要求越来越高,对真菌毒素毒性的总结,可进一步加深对毒素的认识,并为食品、饲料及中药安全性方面相关的法律法规制订提供重要依据。     

Advanced synchrotron-based and globar-sourced molecular (micro) spectroscopy contributions to advances in food and feed research on molecular structure,mycotoxin determination,and molecular nutrition

ABSTRACT

Mycotoxin contamination has been a worldwide problem for food and feeds production for a long time. There is an obviously increased focus of the food and feed industry toward the reduction of mycotoxin concentration in both the raw materials and finished products. Therefore, both effective qualitative and quantitative techniques for the determination of mycotoxins are required to minimize their harmful effects. Conventional wet chemical methods usually are time-consuming, expensive, and rely on complex extraction and cleanup pretreatments. Synchrotron-based and globar-based molecular spectroscopy have shown great potential to be developed as rapid and nondestructive tools for the determination of molecular structure, molecular nutrition and mycotoxins in feed and food. This article reviews the common types of mycotoxins in feed and food, their toxicity, as well as the conventional detection methods. The principle of advanced molecular spectroscopy techniques and their application prospects for mycotoxin detection are discussed. Recent progress in food and feed research with molecular spectroscopy techniques is highlighted. This review provides a potential and insight into how to determine the structure and mycotoxins of feed and food on a molecular basis with advanced Synchrotron-based and globar-based molecular (micro) spectroscopy.     

Molecular biology of Fusarium mycotoxins

As the 20th century ended, Fusarium mycotoxicology entered the age of genomics. With complete genomes of Fusarium graminearum and F. verticillioides and several Fusarium gene expression sequence databases on hand, researchers worldwide are working at a rapid pace to identify mycotoxin biosynthetic and regulatory genes. Seven classes of mycotoxin biosynthetic genes or gene clusters have been identified in Fusarium to date; four are polyketide synthase gene clusters for equisetin, fumonisins, fusarins, and zearalenones. Other Fusarium mycotoxin biosynthetic genes include a terpene cyclase gene cluster for trichothecenes, a cyclic peptide synthetase for enniatins, and a cytochrome P450 for butenolide. From the perspective of the United States Department of Agriculture, the ultimate goal of research on Fusarium molecular biology is to reduce mycotoxins in cereal grains. With this goal in mind, efforts have focused on identifying aspects of mycotoxin biosynthesis and regulation that can be exploited for mycotoxin control. New information on fungal and plant genomes and gene expression will continue to provide information on genes important for fungal-plant interactions and to facilitate the development of targeted approaches for breeding and engineering crops for resistance to Fusarium infection and mycotoxin contamination.     

Review of mycotoxin reduction in food and feed: from prevention in the field to detoxification by adsorption or transformation

Mycotoxins are secondary metabolites present worldwide in agricultural commodities and produced by ?lamentous fungi that cause a toxic response (mycotoxicosis) when ingested by animals. Prevention of mycotoxicoses includes pre- and post-harvest strategies. The best way to reduce the mycotoxin content in food and feed is the prevention of mycotoxin formation in the ?eld, but this is often not sufficient, so other methods are needed. To decontaminate and/or detoxify mycotoxin-contaminated food and feed, the most prevalent approach in the feed industry is the inclusion of sorbent materials in the feed thus obtaining more or less selective removal of toxins by adsorption during passage through the gastrointestinal tract. Another reliable approach is to add enzymes or microorganisms capable of detoxifying some mycotoxins. Through a comprehensive review of published reports on the strategies for mycotoxin removal, this present work aims to update our understanding of mycotoxin removal. It provides an insight into the detoxification of mycotoxin present in food and feed. In the future, more emphasis needs to be placed on adsorption of mycotoxins in the gastrointestinal tract. Concerning the enzymatic transformation of mycotoxins, further efforts are required in understanding detoxification reactions, the toxicity of transformation products and in the characterization of enzymes responsible for transformations.     

镰孢菌毒素的主要类型及其收获前后的生物防控方法

镰孢菌毒素是镰孢菌属真菌产生的多种有毒性的次级代谢产物的总称,在自然界中分布极为广泛,是常见的污染粮食和饲料的真菌毒素种类,严重威胁人畜健康。近年来镰孢菌毒素污染粮食和饲料的问题日益严重,已成为普遍关注的食品安全和饲料安全热点问题之一。由于农产品收获后的物理、化学的脱毒方法存在着脱毒不彻底、营养成分流失和化学试剂残留对人畜健康的不确定性等问题;因此以生物技术为基础的综合防控镰孢菌及其毒素危害的方法成为了近年来的研究热点之一。本文将重点介绍镰孢菌毒素的主要类型及其对动植物的危害,阐述农产品收获前后生物防治镰孢菌及其毒素危害的方法,并探讨各种防控方法的优缺点以及未来可能的研究方向,以期为镰孢菌毒素综合防控策略的制定提供参考。     

A review of postharvest approaches to reduce fungal and mycotoxin contamination of foods

Contamination of agricultural and food products by some fungi species that produce mycotoxins can result in unsafe food and feed. Mycotoxins have been demonstrated to have disease‐causing activities, including carcinogenicity, immune toxicity, teratogenicity, neurotoxicity, nephrotoxicity, and hepatotoxicity. Most of mycotoxins are heat stable and cannot be easily destroyed by conventional thermal food processing or domestic cooking methods. Postharvest approaches to prevent growth of mycotoxin‐producing fungi and detoxify mycotoxins from contaminated food are important topics in food safety research. Physical, chemical, and biological methods have been applied to prevent fungal growth or mycotoxin production, or to reduce mycotoxin content in the postharvest period and contribute toward mitigating against the effects of mycotoxins on human health. This literature review aims to evaluate postharvest approaches that have been applied to control both fungi growth and mycotoxin content in food and discuss their potential for upscaling to industrial scale.     

Novel non-thermal food processing techniques and their mechanism of action in mycotoxins decontamination of foods

This review describes the major food and feed contaminating mycotoxins and provides a thorough insight about non-thermal food processing techniques and their mycotoxin detoxification mechanisms. Cold plasma, pulsed light, pulsed electric field, high pressure processing, and electron beam irradiation are among the techniques discussed. Mycotoxins decontamination is usually achieved through the release of reactive species and inactivation of toxin-producing microorganisms through alteration of cell membrane integrity and genetic makeup. Destruction of the molecular structure of mycotoxins responsible for toxicity also occurs during these processes. These non-thermal methods are effective in decontaminating mycotoxins with varying degrees of efficiency, and some of the methods do complete decontamination of mycotoxins with minimal processing. Despite their promising efficacy in decontaminating mycotoxins, the feasibility of most of these methods requires scale-up with future potential for commercialization and acceptance. Efforts should be made to increase the scalability and adoption of the technologies, especially in low-income countries where mycotoxin contamination is prevalent.     

Molecular strategies for detection and quantification of mycotoxin‐producing Fusarium species: a review

Fusarium contamination is considered a major agricultural problem, which could not only significantly reduce yield and quality of agricultural products, but produce mycotoxins that are virulence factors responsible for many diseases of humans and farm animals. One strategy to identify toxigenic Fusarium species is the use of modern molecular methods, which include the analysis of DNA target regions for differentiation of the Fusarium species, particularly the mycotoxin‐producing Fusarium species such as F. verticillioides and F. graminearum. Additionally, polymerase chain reaction assays are used to determine the genes involved in the biosynthesis of the toxins in order to facilitate a qualitative and quantitative detection of Fusarium‐producing mycotoxins. Also, it is worth mentioning that some factors that modulate the biosynthesis of mycotoxins are not only determined by their biosynthetic gene clusters, but also by environmental conditions. Therefore, all of the aforementioned factors which may affect the molecular diagnosis of mycotoxins will be reviewed and discussed in this paper. © 2014 Society of Chemical Industry     

Impact of nonthermal food processing techniques on mycotoxins and their producing fungi

Mycotoxins are a significant threat to food safety and quality. Over the years, mycotoxins have been detected in almost all food and feed crops without any regional barrier. Conventional techniques for decontamination of mycotoxin involve physical, chemical, and biological methods, but these technologies often impact the quality of food in terms of changes in nutritional and sensory attributes. We examined the effects of nonthermal techniques on mycotoxins and their producing fungi to remove or reduce mycotoxin levels in food products without compromising food quality. Nonthermal technologies employ different lethal agents (including ozone, cold plasma, light, pressure, radiation, ultrasound, electric field, and magnetic field) to degrade mycotoxins while minimising product thermal exposure. However, the degradation pathway and toxicology of treated products need further research for a better understanding. With such food process development and optimisation efforts, food processors can employ various nonthermal technologies as tools for delivering consumer-desired mycotoxin-free food products with intact nutritional and sensory quality.     

Natural Occurrence of Mycotoxins in Food and Feed: Pakistan Perspective

Fungi are commonly present in the environment and can grow under favorable conditions on an extensive variety of substrates. During harvesting, handling, storage, and distribution, agricultural commodities are subjected to infection by toxigenic molds, which may cause spoilage and produce toxic metabolites called mycotoxins. Fungal contamination of various food commodities with consequent exposure of the community to mycotoxins is a hazard that may exist depending on environmental factors, crop health, and soil conditions. Mycotoxins represent serious consequences due to substantial economic loss and risk to health. The environmental conditions of Pakistan with its mostly warm temperature are conducive to growth of toxigenic fungi resulting in mycotoxin production in different food items. Moreover, the poor conditions of storage and deficiency in regulatory measures in food quality control worsen the situation in the country. This review encompasses mycotoxin contamination of food and feed in Pakistan. High concentrations of mycotoxins are found in some commodities that are used on a daily basis in Pakistan, which may be a concern depending on dietary variety and health conditions of individuals in the population. Therefore, the mycotoxin contamination of foodstuff with exceeding levels represents a serious health hazard for the local population. There is a need to conduct more studies to analyze mycotoxin occurrence in all types of food commodities throughout the country. For consumer safety and the country's economy, the regulatory authorities should take into account this issue of contamination, and control strategies should be implemented and the quality control system of food improved.     

天然植物成分防控农产品中真菌毒素的研究进展

真菌毒素是真菌生长过程中产生的次生代谢产物,其对农产品的污染直接威胁人类和动物的生命健康。真菌毒素的预防和脱除是实现食品和饲料工业高质量发展亟待解决的关键问题之一。目前研究者采用了多种策略来防控真菌毒素污染避免健康问题和经济损失,包括抑制真菌生长及真菌毒素生成、去除和降解污染农产品中的真菌毒素、降低真菌毒素生物活性等。利用天然植物成分（Natural plant compounds,NPC）防控真菌毒素污染表现出稳定性强、安全性好和抑制效率高等优势,业已成为研究新趋势。本文综述了近年来NPC防控农产品中真菌毒素污染的不同策略,讨论了相应的作用机制,分析了现阶段采用NPC防控真菌毒素的优势和不足,并展望了在食品工业的应用前景,为开发新的真菌毒素防控试剂提供科学参考。