天然药物及产品真菌毒素研究概况

目的为开展中药中真菌毒素污染研究提供参考。方法对天然药物原料及产品的真菌毒素污染状况、检测方法进行概述。结果与结论真菌毒素作为天然药物的一种主要外源性污染物其危害性已受到普遍关注,不同国家地区的研究结果显示,天然药物真菌毒素污染普遍存在,如黄曲霉毒素、赭曲霉毒素、伏马毒素等多种毒素均有污染。     

真菌毒素快速检测方法研究进展

真菌毒素为真菌的次级代谢产物,具有极强的毒性,对农作物、植物及其副产品均有一定污染,严重威胁人类的健康,为了监测和控制真菌毒素的污染,其快速检测方法已成为近年的研究重点。文章对薄层色谱法、酶联免疫吸附法、胶体金免疫层析法、免疫生物传感器技术、蛋白芯片技术及分子印迹技术在真菌毒素的快速检测中的应用进行综述,并对分子印迹技术应用于真菌毒素快速检测中存在的问题和发展前景进行探讨。     

中药中真菌毒素污染问题

通过搜集有关文献报道。综述了常见真菌毒素（黄曲霉素、赭曲霉素、展青霉素、伏马菌素、玉米赤霉烯嗣）的理化性质、对人体的危害、限量标准、在植物药中的分布情况以及检测方法,指出了中药也应注意真菌毒素的污染,并建议中药也应参照食品建立常见真菌毒素的检测方法与限量标准。     

中药材中真菌毒素免疫检测技术的研究进展

目的 真菌毒素残留是引起中药材及其制品品质变化和用药安全的重要影响因素之一，为加强和提升中药材质量控制，需加强对中药材中的真菌毒素的检测。探讨中药材中真菌毒素免疫检测技术，为该领域的方法研究提供参考。方法 通过查阅国内外文献，总结梳理了不同类型免疫检测技术在中药材真菌毒素检测中的应用。结果 中药材中真菌毒素的免疫检测技术主要以免疫层析技术与酶联免疫吸附检测技术居多，荧光偏振免疫分析法、生物条形码免疫检测技术、电致化学发光免疫传感器、流式微球技术更多地处于科研阶段，产业化不多。结论 随着快速免疫检测技术的研究和发展，将会对未来中药材真菌毒素快速检验和筛查提供广阔的发展空间。     

中药中真菌毒素污染的现状及防控对策

真菌毒素是中药外源性有害残留物污染的一个主要方面.中药在种植、加工、生产、贮存到流通各环节均可能发生真菌毒素的污染,影响中药的用药安全.本文通过概述中药中真菌毒素的防控现状,分析比较国内外相关方面的控制标准及监管模式,系统梳理和剖析中药中真菌毒素污染的特点、规律以及存在的主要问题,提出科学有效防控中药中真菌毒素污染的对...     

150例住院自愿戒毒者脱毒情况分析

目的:了解住院自愿戒毒者脱毒动机,住院环境影响因素,完成脱毒情况调查。方法:统计2003年3月至2005年3月自愿戒毒住院者相关资料,两次以上住院者以一次计,脱毒完成标准以尿检吗啡阴性为准,对统计资料进行整理、分析。结果:平均住院脱毒成功率73%,96%的住院者入院时戒毒动机明确,62%的住院者戒毒决心与住院环境相关,脱毒成功与否主要取决于脱毒者自己的选择。结论:脱毒期的有效管理、心理辅导、行为矫正及不断清除环境中的不良因素影响,有利于脱毒者完成脱毒。     

25种常用中药饮片常见真菌毒素污染分布比较研究

目的 建立中药饮片10种真菌毒素的超高效液相色谱三重四极杆质谱联用方法,并对市售25批中药饮片的真菌毒素污染分布比较研究。方法 样品经70%甲醇超声处理,HLB固相萃取柱净化,Waters ACQUITY UPLC^®BEH C₁₈(2.1 mm×100 mm,1.7 μm)分离,流动相为乙腈-甲醇(1:1)和0.01%甲酸水溶液梯度洗脱,ESI离子源正离子扫描,通过多反应检测模式测定,外标法定量。结果 10种真菌毒素在0.31~250 ng·mL^-1内线性关系良好,相关系数均>0.991,平均加样回收率为83.60%~131.80%,RSD为2.35%~7.85%,10种真菌毒素的检出限为0.14~16.30 ng·kg^-1。25批中药材中,伏马毒素B2检出率最高(28%),其次为呕吐毒素(20%);黄曲霉素B2等4种真菌毒素未检出;果实种子类真菌毒素污染最严重(66.7%),动物类药材真菌毒素污染率最低(20%)。结论 本方法可用于中药饮片中10种真菌毒素的检测;除了黄曲霉毒素外,对于中药饮片中其他真菌毒素应加强监测,其中尤其应注意果实种子类中药的真菌毒素监测。     

穴位按摩对海洛因依赖者脱毒后垂体-甲状腺轴激素水平的影响

目的:观察穴位按摩对海洛因依赖者脱毒不同阶段血清促甲状腺激素(thyroid-stimulating hormone,TSH)、总三碘甲状腺原氨酸(total triiodothyronine,TT_3)与总四碘甲状腺原氨酸(total thyroxine,TT_4)水平的影响。方法:224名海洛因依赖者来自于强制隔离戒毒所,根据其脱毒不同时间段分为急性脱毒期、脱毒巩固期、脱毒康复期、回归社会期四个阶段,并将处于同一脱毒阶段的人员随机分为脱毒对照组与脱毒按摩组。脱毒按摩组人员接受穴位按摩干预12周,脱毒对照组不给予干预。所有被试者分别于干预前、干预8周和12周后接受血清TSH、TT_3、TT_4水平检测。将脱毒各期被试者干预前的血清检测结果与健康对照组进行统计学比较,将脱毒对照组与脱毒按摩组干预前后各指标的差值进行统计学比较。结果:与健康对照组相比,急性脱毒期人员血清TT_3、TT_4显著性降低(P<0.01)。急性脱毒期(女)、脱毒巩固期(男)、回归社会期(男)脱毒按摩组干预8周前后TSH差值与脱毒对照组相比,差异具有显著性(P<0.05);脱毒巩固期(女)脱毒按摩组干预8周前后TT_4、TSH差值与脱毒对照组相比,差异具有显著性(P<0.05);脱毒康复期(男)脱毒按摩组干预8周前后TT_4差值以及12周前后TT_3差值与脱毒对照组相比,差异具有显著性(P<0.05);脱毒康复期(女)脱毒按摩组干预8周前后TT_3、TT_4差值与脱毒对照组相比,差异具有显著性(P<0.05)。结论:海洛因依赖者急性脱毒期甲状腺激素减低;穴位按摩可促进海洛因依赖者脱毒早期TSH、TT_4恢复。该结果提示穴位按摩在戒毒中的作用值得进一步研究。     

脱毒灵胶囊用于海洛因依赖脱毒临床观察

目的:初步评价脱毒灵对海洛因依赖的脱毒效果及不良反应。方法:海洛因依赖戒断症状患者82例,按随机化方法,分为脱毒灵组42例和洛非西定组40例;对脱毒灵与洛非西定进行初步临床观察对照研究。结果:脱毒灵能全面迅速地控制海洛因依赖戒断症状。治疗d 5戒断症状总分减分率脱毒灵组为0.99±0.02,洛非西定组为0.36±0.18;治疗d 10戒断症状总分减分率脱毒灵组为1.00±0.01,洛非西定组为0.78±0.13。所有疗效观察项目脱毒灵组均显著优于洛非西定组,大部分项目P<0.001。脱毒灵组几乎未观察到不良反应和依赖性。结论:脱毒灵对海洛因依赖脱毒效果显著可靠,临床使用安全。     

脱毒灵胶囊3日疗法用于海洛因依赖脱毒临床观察

目的:评价脱毒灵3日疗法对海洛因依赖的脱毒效果及不良反应.方法:海洛因依赖患者123例,随机分为脱毒灵组62例和洛非西定组61例,脱毒灵疗程3日,洛非西定疗程10日,对脱毒灵与洛非西定做临床观察对照研究.结果:脱毒灵能全面迅速地控制海洛因依赖戒断症状.治疗d 3戒断症状总分减分率脱毒灵组为0.86±0.11,洛非西定组为0.24±0.18;治疗d 10戒断症状总分减分率脱毒灵组为1.00±0.01,洛非西定组为0.86±0.10.所有疗效观察项目脱毒灵组均显著优于洛非西定组.脱毒灵组未观察到不良反应.结论:脱毒灵3日脱毒法疗程短,效果显著可靠,临床使用安全.     

Possibilities for the Biological Control of Mycotoxins in Food and Feed

Seeking useful biological agents for mycotoxin detoxification has achieved success in the last twenty years thanks to the participation of many multidisciplinary teams. We have recently witnessed discoveries in the fields of bacterial genetics (inclusive of next-generation sequencing), protein encoding, and bioinformatics that have helped to shape the latest perception of how microorganisms/mycotoxins/environmental factors intertwine and interact, so the road is opened for new breakthroughs. Analysis of literature data related to the biological control of mycotoxins indicates the ability of yeast, bacteria, fungi and enzymes to degrade or adsorb mycotoxins, which increases the safety and quality of susceptible crops, animal feed and, ultimately, food of animal origin (milk, meat and eggs) by preventing the presence of residues. Microbial detoxification (transformation and adsorption) is becoming a trustworthy strategy that leaves no or less toxic compounds and contributes to food security. This review summarizes the data and highlights the importance and prospects of these methods.     

Mycotoxin Metabolism by Edible Insects

Mycotoxins are a group of toxic secondary metabolites produced in the food chain by fungi through the infection of crops both before and after harvest. Mycotoxins are one of the most important food safety concerns due to their severe poisonous and carcinogenic effects on humans and animals upon ingestion. In the last decade, insects have received wide attention as a highly nutritious, efficient and sustainable source of animal-derived protein and caloric energy for feed and food purposes. Many insects have been used to convert food waste into animal feed. As food waste might contain mycotoxins, research has been conducted on the metabolism and detoxification of mycotoxins by edible insects. The mycotoxins that have been studied include aflatoxins, fumonisins, zearalenone (ZEN), vomitoxin or deoxynivalenol (DON), and ochratoxins (OTAs). Aflatoxin metabolism is proved through the production of hydroxylated metabolites by NADPH-dependent reductases and hydroxylases by different insects. ZEN can be metabolized into α- and β-zearalenol. Three DON metabolites, 3-, 15-acetyl-DON, and DON-3-glucoside, have been identified in the insect DON metabolites. Unfortunately, the resulting metabolites, involved enzymes, and detoxification mechanisms of OTAs and fumonisins within insects have yet to be identified. Previous studies have been focused on the insect tolerance to mycotoxins and the produced metabolites; further research needs to be conducted to understand the exact enzymes and pathways that are involved.     

Bacterial tests as indicators for the detoxification of the mycotoxin penicillic acid by ammonia treatment

The detoxification of penicillic acid by reaction with ammonia was examined by means of a polymerase assay using two strains of Escherichia coli (pol A+ and pol A-1) and a recombination assay using two strains of Bacillus subtilis (rec+ and rec-). A 100-fold surplus of ammonia added to penicillic acid abolished the cytotoxic and genotoxic effects of penicillic acid towards the bacteria under the test conditions. The study presents the possibility of detoxifying mycotoxins in feeds by ammonia treatment and demonstrates the suitability of bacterial assays as indicators for mycotoxins.     

Detoxification of patulin and ochratoxin A, two abundant mycotoxins, by lactic acid bacteria.

Aim of the present study was to investigate the detoxification of two abundant mycotoxins, namely ochratoxin A (OTA) and patulin (PAT) which are frequently found in human foods, by lactic acid bacteria. The removal of the two mycotoxins from liquid medium by thirty different LAB strains was analyzed in a screening trial by the use of HPLC coupled with UV- or fluorescence detection. Two highly effective strains were identified; Lactobacillus acidophilus VM 20 caused a decrease of OTA by > or = 95% and Bifidobacterium animalis VM 12 reduced PAT levels by 80%. Subsequently experiments showed that the binding of these compounds depends on different parameters, i.e. the concentration of toxins, the cell density, the pH-value and on the viability of the bacteria. To proof that the decrease of the toxins by LAB from liquid medium results in a reduction of their toxic properties, micronucleus (MCN) assays were conducted with a human derived hepatoma cell line (HepG2). Indeed, a substantial decrease (39-59%) of OTA and PAT induced MCN formation was observed with the most effective strains detected in the chemical analyses. Furthermore, also the inhibition of the cell division rates by the toxins was significantly reduced. These findings indicate that certain LAB strains are able to detoxify the two toxins and may be useful to protect humans and/or animals against the adverse health effects of these compounds.     

Contamination,Detection and Control of Mycotoxins in Fruits and Vegetables

Mycotoxins are secondary metabolites produced by pathogenic fungi that colonize fruits and vegetables either during harvesting or during storage. Mycotoxin contamination in fruits and vegetables has been a major problem worldwide, which poses a serious threat to human and animal health through the food chain. This review systematically describes the major mycotoxigenic fungi and the produced mycotoxins in fruits and vegetables, analyzes recent mycotoxin detection technologies including chromatography coupled with detector (i.e., mass, ultraviolet, fluorescence, etc.) technology, electrochemical biosensors technology and immunological techniques, as well as summarizes the degradation and detoxification technologies of mycotoxins in fruits and vegetables, including physical, chemical and biological methods. The future prospect is also proposed to provide an overview and suggestions for future mycotoxin research directions.     

Deficient Glutathione in the Pathophysiology of Mycotoxin-Related Illness

Evidence for the role of oxidative stress in the pathophysiology of mycotoxin-related illness is increasing. The glutathione antioxidant and detoxification systems play a major role in the antioxidant function of cells. Exposure to mycotoxins in humans requires the production of glutathione on an “as needed” basis. Research suggests that mycotoxins can decrease the formation of glutathione due to decreased gene expression of the enzymes needed to form glutathione. Mycotoxin-related compromise of glutathione production can result in an excess of oxidative stress that leads to tissue damage and systemic illness. The review discusses the mechanisms by which mycotoxin-related deficiency of glutathione may lead to both acute and chronic illnesses.     

Effects of Deoxynivalenol and Fumonisins on Broiler Gut Cytoprotective Capacity

Mycotoxins are a crucial problem for poultry production worldwide. Two of the most frequently found mycotoxins in feedstuffs are deoxynivalenol (DON) and fumonisins (FUM) which adversely affect gut health and poultry performance. The current knowledge on DON and FUM effects on broiler responses relevant for gut detoxification, antioxidant capacity, and health is still unclear. The aim of this study was to assess a range of selected molecular intestinal biomarkers for their responsiveness to the maximum allowable European Union dietary levels for DON (5 mg/kg) and FUM (20 mg/kg) in broilers. For the experimental purpose, a challenge diet was formulated, and biomarkers relevant for detoxification, antioxidant response, stress, inflammation, and integrity were profiled across the broiler intestine. The results reveal that DON significantly (p < 0.05) induced aryl hydrocarbon receptor (AhR) and cytochrome P450 enzyme (CYP) expression mainly at the duodenum. Moreover, DON and FUM had specific significant (p < 0.05) effects on the antioxidant response, stress, inflammation, and integrity depending on the intestinal segment. Consequently, broiler molecular responses to DON and FUM assessed via a powerful palette of biomarkers were shown to be mycotoxin and intestinal site specific. The study findings could be highly relevant for assessing various dietary bioactive components for protection against mycotoxins.     

Antigenotoxic studies of different substances to reduce the DNA damage induced by aflatoxin B(1) and ochratoxin A

Mycotoxins are produced mainly by the mycelial structure of filamentous fungi, or more specifically, molds. These secondary metabolites are synthesized during the end of the exponential growth phase and appear to have no biochemical significance in fungal growth and development. The contamination of foods and feeds with mycotoxins is a significant problem for the adverse effects on humans, animals, and crops that result in illnesses and economic losses. The toxic effect of the ingestion of mycotoxins in humans and animals depends on a number of factors including intake levels, duration of exposure, toxin species, mechanisms of action, metabolism, and defense mechanisms. In general, the consumption of contaminated food and feed with mycotoxin induces to neurotoxic, immunosuppressive, teratogenic, mutagenic, and carcinogenic effect in humans and/or animals. The most significant mycotoxins in terms of public health and agronomic perspective include the aflatoxins, ochratoxin A (OTA), trichothecenes, fumonisins, patulin, and the ergot alkaloids. Due to the detrimental effects of these mycotoxins, several strategies have been developed in order to reduce the risk of exposure. These include the degradation, destruction, inactivation or removal of mycotoxins through chemical, physical and biological methods. However, the results obtained with these methods have not been optimal, because they may change the organoleptic characteristics and nutritional values of food. Another alternative strategy to prevent or reduce the toxic effects of mycotoxins is by applying antimutagenic agents. These substances act according to several extra- or intracellular mechanisms, their main goal being to avoid the interaction of mycotoxins with DNA; as a consequence of their action, these agents would inhibit mutagenesis and carcinogenesis. This article reviews the main strategies used to control AFB(1) and ochratoxin A and contains an analysis of some antigenotoxic substances that reduce the DNA damage caused by these mycotoxins.     

Mineral adsorbents for prevention of mycotoxins in animal feeds

Abstract

Mycotoxins are toxic metabolites produced by several fungi species, with the aflatoxins, fumonisins, zearalenone, trichothecenes and ochratoxin A being the most important found in feedstuffs. The economic impact caused by mycotoxins motivated the investigation of detoxification strategies to reduce its bioavailability by enterosorption. Although there are several types of adsorbents, the efficiency of the adsorption depends on the physical and chemical characteristics of both the adsorbent and the mycotoxin. This review describes the most important types of mineral adsorbents [aluminosilicates, HSCAS, bentonites (montmorillonites), zeolites, sepiolite, diatomite and activated carbons] used in feeds, especially for poultry and pigs, and their adsorption mechanisms.     

Zearalenone and Its Derivatives α-Zearalenol and β-Zearalenol Decontamination by Saccharomyces cerevisiae Strains Isolated from Bovine Forage

Zearalenone (ZEA) and its derivatives are mycotoxins with estrogenic effects on mammals. The biotransformation for ZEA in animals involves the formation of two major metabolites, α- and β-zearalenol (α-ZOL and β-ZOL), which are subsequently conjugated with glucuronic acid. The capability of Saccharomyces cerevisiae strains isolated from silage to eliminate ZEA and its derivatives α-ZOL and β-ZOL was investigated as, also, the mechanisms involved. Strains were grown on Yeast Extract-Peptone-Dextrose medium supplemented with the mycotoxins and their elimination from medium was quantified over time by HPLC-FL. A significant effect on the concentration of ZEA was observed, as all the tested strains were able to eliminate more than 90% of the mycotoxin from the culture medium in two days. The observed elimination was mainly due to ZEA biotransformation into β-ZOL (53%) and α-ZOL (8%) rather than to its adsorption to yeast cells walls. Further, the biotransformation of α-ZOL was not observed but a small amount of β-ZOL (6%) disappeared from culture medium. ZEA biotransformation by yeasts may not be regarded as a full detoxification process because both main end-products are still estrogenic. Nonetheless, it was observed that the biotransformation favors the formation of β-ZOL which is less estrogenic than ZEA and α-ZOL. This metabolic effect is only possible if active strains are used as feed additives and may play a role in the detoxification performance of products with viable S. cerevisiae cells.