全自动在线免疫亲和固相萃取-液相色谱法快速定量检测植物油中的黄曲霉毒素B1

黄曲霉毒素(AFT)是主要由黄曲霉(Aspergillus flavus)、红绶曲霉(Aspergillus nomius)和寄生霉菌(Aspergillus parasiticus)所产生的次生代谢产物,包括AFTG2、AFTG1、AFTB2和AFTB1。其中,AFTB1的毒性最大。早在2002年AFTB1就被国际癌症研究机构(International Agency for Research on Cancer)归类为I类致癌物,其致癌性和致突变毒性对人类健康构成了重大威胁。我国《食品安全国家标准食品中真菌毒素限量》(GB2761-2011)中对食品中AFTB1的最低限量规定为0.5μg/kg,以控制人体对AFTB1的摄入量,从而使其对人体的危害降到最低。     

黄曲霉毒素的危害及检测方法研究进展

黄曲霉毒素(Aflatoxins,AFT)主要是由真菌寄生曲霉和黄曲霉产生的次生代谢产物,在自然界中普遍存在,尤其在湿热的环境中极易产生,由于其具有极强的致癌性,研究其检测方法极其重要.本文主要介绍黄曲霉毒素的危害、检测技术及黄曲霉的残留限量标准,并对应用较广的高效液相色谱-质谱联用法、液相色谱法、薄层色谱和酶联免疫吸...     

农产品免黄曲霉毒素污染储藏新法

众所周知,食品或饲料如被黄曲霉毒素污染,将对人和家畜健康产生极大危害。此污染源自于黄曲霉与寄生曲霉(它们的代谢产物为黄曲霉毒素)。黄曲霉与寄生曲霉往往作为储藏真菌存在于许多农产品中。一旦条件有利,它们便大量繁殖,与此同时产生黄曲霉毒素造成污染。经研究发现:2-氯乙基磷酸(CEPA,一种能产生乙烯的化合物)能抑制黄曲霉与寄生曲霉菌株生物合成黄曲霉毒素。本研究为检验用CEPA抑制黄曲霉毒素污染花生与玉米的效果。     

食品中黄曲霉毒素的降解方法的研究进展

黄曲霉毒素(aflatoxin, AFT)是一种致癌性较强的剧毒物质,主要由曲霉属真菌产生,广泛存在于食品及其动物饲料中,严重危害着人体健康。黄曲霉毒素具有稳定的结构,一般的处理很难将其去除。因此如何将黄曲霉毒素有效降解确保食品安全一直是研究的重点。本文主要介绍了近些年黄曲霉毒素的物理降解法、化学降解法和生物降解法的研究进展,以期为食品中黄曲霉毒素的降解提供参考。     

油脂中黄曲霉毒素污染及吸附脱除的研究进展

黄曲霉毒素是在湿热条件下主要由黄曲霉(Aspergillus flavus)和寄生曲霉(Aspergillus parasiticus)产生的一组杂环芳烃类次生代谢产物，具有突出的三致效应，严重危害生态环境和人体健康，因此，黄曲霉毒素的控制已成为国内外科研人员关注的研究热点之一。在食用油的净化技术中，吸附法因其操作简单、效率高、成本低等优点，被认为是控制食用油中微量黄曲霉毒素的主要技术。本文对油脂中黄曲霉毒素污染影响因素和吸附脱除法进行了较为详细的概述，对π-π相互作用、π-络合、酸碱作用和疏水相互作用等吸附机理进行了简单阐述，重点综述了各种吸附剂在该领域的研究进展和未来发展趋势，为开发出更高效的吸附剂用来消减油脂中的黄曲霉毒素提供了研究思路。     

黄曲霉毒素B1测定方法概述

黄曲霉毒素（Aflatoxins，简写AFT）是黄曲霉、寄生曲霉及温特曲霉等产毒菌株的代谢物（后者产量较少），是一群结构类似的化合物。AFF属剧毒物质，其毒性比氰化钾还高，也是目前最强的化学致癌物，其中AFT．B1的毒性和致癌性最强。因此对AFT检测国内外进行了大量的研究，积累了丰富的科学资料。本文主要综述AFT．B1的一些检测方法。     

免疫法快速检测食品中黄曲霉毒素的研究进展

黄曲霉毒素(aflatoxin)是由霉菌黄曲霉和寄生曲霉感染后产生的次生代谢产物,是自然界中毒性最强的化合物之一,被世界卫生组织的癌症研究机构(IARC)划定为I类致癌物质,与肝癌的发生密切相关。黄曲霉毒素很容易污染谷物、坚果、香料、植物油脂、乳类及其制品等多种食品。因此,研究出快速、准确、高效的食品中黄曲霉毒素的检测方法是政府、企业和研究者们一直以来的共同目标。本文综述了近年来基于免疫技术发展的各种快速检测黄曲霉毒素方法,主要包括酶联免疫吸附测定法、胶体金免疫层析法、免疫传感器、免疫亲和柱-高效液相色谱法、免疫荧光法、放射免疫法、时间分辨荧光免疫分析法和量子点探针法的基本原理、适用范围、检测效果、优缺点及国内外应用等方面进展,为今后研发更优的检测黄曲霉素新方法提供借鉴。     

微柱层析法测定酱油、醋中的黄曲霉毒素

一、前言黄曲霉毒素是黄曲霉和寄生曲霉的代谢产物,是目前发现的最强的化学致癌物质。我国在大量调查研究及科学实验的基础上已制订出国家食品卫生标准(GBn—51—77)。黄曲霉毒素(AFT)是一类结构类似的化合     

黄曲霉毒素对人体的危害

黄曲霉毒素(简称AFT),是黄曲霉、寄生曲霉的代谢产物.黄曲霉素的分子量为312~346,难溶于水,易溶于油和甲醇、丙酮及氯仿等有机溶剂,在PH9~10的强碱溶液中分解迅速.黄曲霉毒素属于毒性物质,其毒性比氰化钾还高,人摄入大量黄曲霉毒素后可发生急性中毒.当微量持续被摄入人体后,也可造成慢性中毒.黄曲霉毒素主要污染粮     

HPLC技术分析测定黄曲霉毒素的研究进展

黄曲霉毒素是真菌(如黄曲霉和寄生曲霉)产生的一类有毒的代谢产物,具有很强毒性,能强烈破坏人和动物的肝脏组织,严重时会导致肝癌甚至死亡。现已受到越来越多人群的关注。本文分别介绍柱前衍生化、柱后衍生化以及串联质谱配合高效液相色谱技术分析食品里黄曲霉毒素的方法及研究进展。     

Effects of Tropical Citrus Essential Oils on Growth, Aflatoxin Production, and Ultrastructure Alterations of Aspergillus flavus and Aspergillus parasiticus

Ethyl acetate extracts and hydrodistillated essential oils from five cultivars of tropical citrus epicarps were evaluated for their inhibitory activities against Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus, Aspergillus parasiticus, and Penicillium sp. using disk diffusion and broth microdilution assays. Essential oils prepared from kaffir lime (Citrus hystrix DC) and acid lime (Citrus aurantifolia Swingle) epicarps exhibited stronger antifungal activity to all fungi than their ethyl acetate extracts with minimum inhibitory concentration and minimum fungicidal concentration values of 0.56 and 1.13 mg/ml (dry matter), respectively, against aflatoxin-producing A. flavus and A. parasiticus. The dominant components of the essential oil from kaffir lime were limonene, citronellol, linalool, o-cymene, and camphene, whereas limonene and p-cymene were major components of acid lime essential oil. Pure limonene, citronellal, and citronellol were five to six times less fungicidal than the natural essential oils, indicating the synergistic activity of many active compounds present in the oils. Kaffir and acid lime essential oils significantly reduced aflatoxin production of A. flavus and A. parasiticus, particularly lime essential oil, which completely inhibited growth and aflatoxin production of A. flavus at the concentration of 2.25 mg/ml. Target cell damage caused by acid lime essential oil was investigated under transmission electron microscopy. Destructive alterations of plasma and nucleus membrane, loss of cytoplasm, vacuole fusion, and detachment of fibrillar layer were clearly exhibited in essential-oil-treated cells.     

Impact of volatile compounds generated by essential oils on Aspergillus section Flavi growth parameters and aflatoxin accumulation

BACKGROUND: The advantage of essential oils is their bioactivity in the vapour phase, a characteristic that makes them attractive as possible fumigants for stored grain protection. In this study the antifungal and antiaflatoxigenic effects of the volatile fractions of five essential oils (EOs) were evaluated by vapour contact on Aspergillus section Flavi isolates. RESULTS: In maize meal extract agar the volatile fractions of Pimpinella anisum L. (anise), Pëumus boldus Mol. (boldus), Hedeoma multiflora Benth. (mountain thyme), Lippia turbinata var. integrifolia (Griseb.) (poleo) and Syzygium aromaticum L. (clove) were able to decrease the growth rate and lag phase of aflatoxigenic isolates. Boldus EO showed the best antifungal effect on Aspergillus section Flavi growth rate. In sterilised maize grains, boldus and poleo EOs showed antifungal effects on growth rate and aflatoxin accumulation. The volatile fraction of boldus EO completely inhibited the growth of isolates at water activity (a_w) levels of 0.955, 0.930 and 0.900, while poleo EO showed this effect only at the lower a_w levels (0.930 and 0.900). All aflatoxigenic isolates showed reduced total aflatoxin accumulation in the presence of boldus EO under all a_w conditions. CONCLUSION: These findings clearly indicate that the volatile fraction of boldus EO could be used to control aflatoxigenic fungi in stored maize. Copyright © 2009 Society of Chemical Industry     

Inhibition of heat resistant molds: Aspergillus fumigatus and Paecilomyces variotii by some plant essential oils

In this study, the inhibitory properties of some essential oils including citrus (Citrus sinensis L. Osbeck), laurel (Laurus nobilis L.), myrtle (Myrtus communis L.), oregano (Origanum vulgare L.), and savory (Satureja thymbra L.) were investigated against the heat resistant molds Aspergillus fumigatus and Paecilomyces variotii isolated from margarine in a previous study in order to assess the potential for using these essential oils as a natural food preservative. In this study, the essential oils of the plants were obtained by steam distillation using Clevenger apparatus and were tested for antifungal activities at 0.25, 0.50, and 1.00% concentrations. Inhibitory effects of the essential oils on the growth of the fungi followed the sequence: oregano=citrus>savory>laurel>myrtle. P. variotii was more resistant against the essential oils than A. fumigatus.     

Antiaflatoxigenic and antioxidant activity of an essential oil from Ageratum conyzoides L.

BACKGROUND: Aflatoxin contamination of various commodities can occur as a result of infection, mainly by Aspergillus flavus and Aspergillus parasiticus. Every year, almost 25% of the world's food supply is contaminated by mycotoxins. Aflatoxins B₁, B₂, G₁ and G₂, which occur naturally, are significant contaminants of a wide variety of commodities. A number of biological activities have been associated with Ageratum conyzoides. We have therefore investigated the antiaflatoxigenic, antioxidant and antimicrobial activity of essential oils of A. conyzoides. This could help to turn A. conyzoides, a nuisance weed, into a resource. RESULTS: The essential oil of Ageratum conyzoides L. shows the presence of 12 compounds when analyzed by gas chromatography–mass spectrometry. The growth and aflatoxin production of the toxigenic strain Aspergillus parasiticus was completely inhibited by essential oil. All the studied concentrations of the oil demonstrate a reduction in mycelia growth and decreased production of different aflatoxins in fungi, as revealed by liquid chomatographic–tandem mass spectrometric analysis. Volatiles from macerated green leaf tissue of A. conyzoides were also effective against A. parasiticus. The strongest antibacterial activity was observed against the bacteria Staphylococcus aureus and Bacillus subtilis in a disk diffusion bioassay. Essential oil and methanol extract of A. conyzoides L. were assayed for their antioxidant activity. Methanol extract showed the highest antioxidant activity in FRAP and DPPH assay, whereas essential oil showed greater lipid peroxidation inhibition than methanol extract. CONCLUSION: The plant's ethno‐medicinal importance, antioxidant potential, inhibitory activity against the Aspergillus group of fungi and production of aflatoxins may add a new dimension to its usefulness in the protection of stored product. Copyright © 2010 Society of Chemical Industry     

植物源天然产物对黄曲霉和黄曲霉毒素B_1的抑制作用研究进展

黄曲霉毒素B1(aflatoxin B1,AFB1)是化学物质中致癌性最强的一种,对人和动物的健康具有极大的威胁,尤其是对肝脏的损害。AFB1是谷物和粮油中最为多见的真菌毒素,危害性也最强,长期低剂量的摄入AFB1除了会导致肝脏损伤和诱发肝癌之外,也会损害人体的其他器官。因此,能够有效防护人体免遭AFB1损伤的功能食品和新型保健药物已成为研究重点。近年来,天然产物因其具有生物活性显著、副作用小、多靶点等优点而备受关注,多种植物源天然产物已被报道能够抑制黄曲霉的生长产毒和AFB1的毒性作用。该文主要综述了植物源天然产物对黄曲霉生长产毒和AFB1毒性作用的抑制作用以及其相关抑制机制,为进一步开展AFB1毒性损伤的防护研究工作,开发能降低AFB1对人和动物的毒性损伤的新型保健药物和功能食品提供参考。     

Efficacy of Some Essential Oils Against Aspergillus flavus with Special Reference to Lippia alba Oil an Inhibitor of Fungal Proliferation and Aflatoxin B1 Production in Green Gram Seeds during Storage

During mycofloral analysis of green gram (Vigna radiata (L.) R. Wilczek) seed samples taken from different grocery stores by agar and standard blotter paper methods, 5 fungal species were identified, of which Aspergillus flavus exhibited higher relative frequency (75.20% to 80.60%) and was found to produce aflatoxin B₁. On screening of 11 plant essential oils against this mycotoxigenic fungi, Lippia alba essential oil was found to be most effective and showed absolute inhibition of mycelia growth at 0.28 μL/mL. The oil of L. alba was fungistatic and fungicidal at 0.14 and 0.28 μL/mL, respectively. Oil had broad range of fungitoxicity at its MIC value and was absolutely inhibited the AFB1 production level at 2.0 μL/mL. Chemical analysis of this oil revealed geranial (36.9%) and neral (29.3%) as major components followed by myrcene (18.6%). Application of a dose of 80 μL/0.25 L air of Lippia oil in the storage system significantly inhibited the fungal proliferation and aflatoxin production without affecting the seed germination rate. By the virtue of fungicidal, antiaflatoxigenic nature and potent efficacy in storage food system, L. alba oil can be commercialized as botanical fungicide for the protection of green gram seeds during storage.     

In vitro antifungal activity of terpinen-4-ol,eugenol, carvone, 1,8-cineole (eucalyptol) and thymol against mycotoxigenic plant pathogens

The aim of this study was to examine the effect of five naturally occurring compounds from essential oils on 10 different species of mycotoxigenic fungi involved in several plant diseases. The antifungal activities of terpinen-4-ol, eugenol, carvone, 1,8-cineole (eucalyptol) and thymol were observed in vitro on Fusarium subglutinans, Fusarium cerealis, Fusarium verticillioides, Fusarium proliferatum, Fusarium oxysporum, Fusarium sporotrichioides, Aspergillus tubingensis, Aspergillus carbonarius, Alternaria alternata and Penicillium sp. The naturally occurring compounds tested showed toxic effects on in vitro mycelium growth of all fungal species but with different level of potency. The results are encouraging for further investigations of in planta antifungal activities of these essential oils components.     

Assessment of Thymus vulgaris L. essential oil as a safe botanical preservative against post harvest fungal infestation of food commodities

A total of 14 odoriferous angiospermic essential oils were tested against the toxigenic strain of Aspergillus flavus. The essential oil of Thymus vulgaris L. showed highest antifungal efficacy. The thyme oil absolutely inhibited the mycelial growth of A. flavus at 0.7 μl ml^− 1 and exhibited a broad fungitoxic spectrum against eight different food contaminating fungi viz. Fusarium oxysporum, Cladosporium herbarum, Curvularia lunata, Aspergillus terreus, Aspergillus niger, Aspergillus fumigatus, Alternaria alternata and Botryodiploidia theobromae. The oil also showed significant antiaflatoxigenic efficacy as it completely arrested the aflatoxin B₁ production at 0.6 μl ml^− 1. Thyme oil as fungitoxicant was also found superior over most of the prevalent synthetic fungicides. The LC₅₀ of thyme oil against mice was recorded as 7142.85 μl kg^− 1 body weight indicating its non-mammalian toxicity and strengthening its safe exploitation as preservative for stored food commodities. The findings recommend the thyme oil as potential botanical preservative in eco-friendly control of biodeterioration of food commodities during storage.

Industrial relevance

The thyme essential oil may be recommended for large scale application as a plant based preservative for stored food items because of its strong antifungal as well as antiaflatoxigenic efficacy. Because of broad antimicrobial spectrum, more efficacy over prevalent synthetic preservatives as well as non-mammalian toxicity, the thyme essential oil may be formulated as a safe and economical plant based preservative against post harvest fungal infestation and aflatoxin contamination of food commodities.     

Evaluation of chemically characterised essential oils of Coleus aromaticus,Hyptis suaveolens and Ageratum conyzoides against storage fungi and aflatoxin contamination of food commodities

The result of the present investigation explores the efficacy of chemically characterised essential oils (EOs) of Coleus aromaticus, Hyptis suaveolens and Ageratum conyzoides as antifungal and antiaflatoxigenic agent against some storage fungi and the toxigenic strain of Aspergillus flavus (Saktiman 3NSt). Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of these EOs were also determined against the toxigenic strain of A. flavus (Saktiman 3NSt). The EO from C. aromaticus was found to be most effective exhibiting MIC and MFC at 0.1μL mL^?1. The EOs also completely checked aflatoxin B₁ synthesis in concentration‐dependent manner. In addition, fumigation of stored wheat samples with EOs exhibited remarkable protection (>80%) from fungal infestation showing their efficacy during in vivo storage conditions. Based on the results of the present investigation, the EOs of C. aromaticus, H. suaveolens and A. conyzoides may be recommended as novel plant‐based antifungal and aflatoxin B₁ suppressor over the synthetic preservatives.     

Antifungal Effect of Allium tuberosum,Cinnamomum cassia,and Pogostemon cablin Essential Oils and Their Components Against Population of Aspergillus Species

Antifungal activity of Allium tuberosum (AT), Cinnamomum cassia (CC), and Pogostemon cablin (Patchouli, P) essential oils against Aspergillus flavus strains 3.2758 and 3.4408 and Aspergillus oryzae was tested at 2 water activity levels (a_w: 0.95 and 0.98). Main components of tested essential oils were: allyl trisulfide 40.05% (AT), cinnamaldehyde 87.23% (CC), and patchouli alcohol 44.52% (P). The minimal inhibitory concentration of the plant essential oils against A. flavus strains 3.2758 and 3.4408 and A. oryzae was 250 ppm (A. tuberosum and C. cassia), whereas Patchouli essential oil inhibited fungi at concentration > 1500 ppm. The essential oils exhibited suppression effect on colony growth at all concentrations (100, 175, and 250 ppm for A. tuberosum; 25, 50, and 75 for C. cassia; 100, 250, and 500 for P. cablin essential oil). Results of the study represent a solution for possible application of essential oil of C. cassia in different food systems due to its strong inhibitory effect against tested Aspergillus species. In real food system (table grapes), C. cassia essential oil exhibited stronger antifungal activity compared to cinnamaldehyde.