粮食中主要真菌毒素危害及联合毒性研究进展

真菌毒素由丝状真菌代谢产生,具有很强的毒性。基于人类肝癌细胞系（HepG2细胞）能形成稳定的细胞系,分泌多种血浆蛋白,可以有效评估真菌毒素的体外毒性。文章综述了主要真菌毒素对粮食的危害,以及真菌毒素间联合毒性对人体细胞产生的副作用,对未来预测和预防粮食中真菌毒素对人体和动物健康影响意义重大。     

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     

米曲霉次生代谢产物真菌毒素研究进展

米曲霉是亚洲发酵食品生产使用的主要丝状真菌,可产生丰富的次生代谢产物,其中一些米曲霉菌株会代谢产生少量的真菌毒素,这些米曲霉真菌毒素可能会对人体健康造成危害。文章从米曲霉真菌毒素的起源、病理毒性、检测方法与防治等方面对4种真菌毒素的研究进展进行了综述。     

粮食中的真菌毒素

正温暖潮湿的季节里食物容易发霉,罪魁祸首就是霉菌,当霉菌带有产毒基因且环境条件适宜时,便会产生真菌毒素。真菌可以分为对人体有益和对人体有害两大类,冬虫夏草、灵芝、木耳等真菌是有益真菌,某些真菌如曲霉菌、青霉菌、镰刀菌等真菌危害人体健康,是有害真菌,真菌毒素就是由此类真菌代谢产生的物质。根据联合国粮农组织的调查,全球每年约有25%的粮食受到真菌毒素污染,约有2%的农作物因污染严重而失去利用价值。然而,并不是所有受真菌毒素污染的粮食都能被消费者     

粮食中隐蔽型真菌毒素污染的研究进展

真菌毒素污染是影响全球食品安全问题的重要因素之一。真菌毒素是真菌产生的次级代谢产物,对人体、动植物皆可产生危害。自然条件下,真菌毒素分子可与葡萄糖、丙二酸或谷胱甘肽等极性较强的基团结合,生成结合型真菌毒素。由于毒素结构发生改变,现有的常规检测手段不能有效地检测其存在,因此称其为隐蔽型真菌毒素(masked mycotoxins)。已有文献报道,隐蔽型真菌毒素往往与其原型同时存在于粮食中,而隐蔽型毒素在进入人和动物体内后,经水解、氧化还原等代谢过程,可释放出有毒的毒素原型分子,给食品安全、人和动物健康造成严重隐患。因此对隐蔽型真菌毒素的形成机制、污染状况和毒理研究应尽快展开。本文综述了国内外近几年以来几种常见隐蔽型真菌毒素的最新研究进展,为隐蔽型真菌毒素的研究提供有价值的参考。     

真菌毒素暴露对组蛋白修饰影响的研究进展

天然存在的霉菌毒素的暴露会影响人体健康。环境中的许多真菌毒素会对组蛋白修饰状态产生影响,这种表观遗传改变在疾病的发生与发展中往往发挥重要作用。近年来,真菌毒素在表观遗传学层面的致毒机制也已成为研究热点。然而截止目前,专注于真菌毒素致毒的组蛋白修饰方面的综述仍然缺乏。文章综述了黄曲霉毒素(AFB1)、脱氧雪腐镰刀菌烯醇(DON)、赭曲霉毒素(OTA)、伏马毒素(FB1)、T-2毒素等多种真菌毒素对组蛋白修饰影响的最新研究进展及其可能的作用机制,为进一步揭示环境毒素污染对人体健康的影响及食品安全风险评估提供了参考依据。     

鱼干中真菌毒素的污染及其防控措施研究进展

鱼干在制作和贮藏过程中易受到环境中真菌的污染，并产生真菌毒素。真菌毒素性质稳定，可通过食物链和生物富集作用直接或间接的危害人体健康。该研究对鱼干制品中真菌毒素的污染危害、产生原因及物理、化学、生物等防控方法进行系统综述，以期为水产干制品中真菌毒素的防控、保障其质量安全并提高市场竞争力提供理论基础。     

果蔬常见病原菌及真菌毒素的防控技术研究进展

果蔬在田间的生长过程以及采摘后的贮存、运输和加工过程中, 易发生真菌性病害, 不仅可引起腐烂或腐败, 带来严重的经济损失, 部分病原菌还可能产生真菌毒素对人体造成潜在危害。真菌毒素是一类由丝状真菌在适宜条件下产生的有毒次级代谢产物, 是继农药残留、重金属污染后, 影响果蔬质量安全的又一类关键风险因子, 具有强毒性。链格孢毒素、赭曲霉毒素、展青霉素是存在于果蔬及其制品中主要的真菌毒素种类。本文综述了近年来果蔬中常见病原真菌及其真菌毒素, 并阐述了真菌毒素防控方法, 包括物理、化学和生物方法, 对未来果蔬中真菌毒素的防控研究方向进行了展望, 以期为该领域研究者提供参考。     

食用植物油中真菌毒素研究进展

真菌毒素早已被证实是一类对人类极其有害的物质，食用植物油中含有的多种真菌毒素可致癌、致突变，对人体产生遗传毒性。本文就食用植物油中真菌毒素的来源、危害、检测方法、限量标准、污染现状和污染防治等方面的研究进展进行了综述。     

粮油食品中真菌毒素的研究进展

真菌毒素是一些真菌次级代谢产物,也是粮油食品的主要污染物之一。本文简述了粮油食品中典型的真菌毒素的性质,对人体和动物的危害;重点介绍了真菌毒素的分析过程。     

Genetic parameters for yield traits of Holsteins, including lactose and somatic cell score.

First lactation milk, fat, protein, and lactose yields and percentage yields were analyzed using a multiple-trait sire model including herd-year-season, sire group, and age of cow as fixed effects. Somatic cell score was fit both as a fixed effect in the model and as an additional dependent variable in two analyses with almost identical results. Variance components were estimated using REML with an expectation-maximization algorithm including sire relationships. Lactose means ranged from 4.84 to 4.97% across three dairy breeds. Data used to estimate variance components were first lactation Holstein records collected from 1986 to 1988 from 5246 daughters of 392 AI sires. Heritability estimates were .30, .29, .27, and .26 for milk, fat, protein, and lactose yields; .45, .47, and .53 for fat, protein, and lactose percentage yields; and .16 for somatic cell score. Genetic correlations of lactose percentage with milk, fat, protein, fat and protein percentages, and somatic cell score were -.30, -.16, -.21, .10, .29, and -.11, respectively, and phenotypic correlations were -.08, -.02, .01, .11, .29, and -.15.     

TOXIGENIC FUNGI ISOLATED FROM LATE-SEASON PECANS

Of 1978 fungal colonies isolated on malt-salt agar from twenty 5-kg samples of pecans harvested late in the season, 39% were Cladosporium, 21% were Penicillium, 9% were Alternaria or Epicoccum, 8% Pestalotia or Monochaeta, 4% Trichothecium, 4% Aspergillus niger, and less than 2% were Fusarium, Phomopsis, Rhizopus, Aspergillus, and miscellaneous genera. Forty-four of 260 representative isolates were persistently toxic to day-old cockerels. Toxigenic Penicillium spp. included P. citrinum, P. terrestre, P. cyclopium, P. funiculosum, P. roquefortii, P. purpurogenum, P. rubrum, and P. rugulosum. Toxigenic isolates of other genera included Aspergillus fiavus, A. cervinus, Alternaria alternata, Trichothecium roseum, Pestalotia sp., and Fusarium spp. Additional key words are Carya illinoensis, mycotoxins.     

Enterococcus faecalis and Enterococcus faecium isolates from milk,beef, and chicken and their antibiotic resistance

The occurrence and antibiotic resistance of enterococci, especially Enterococcus faecalis and Enterococcus faecium, in milk, beef, and chicken in Gaborone, Botswana, were studied. Enterococci were isolated from these sources with the use of bile esculin agar and identified with API 20 Strep kits. Antibiotic resistance was determined by the disk diffusion method. The antibiotics tested were vancomycin, teicoplanin, ampicillin, tetracycline, and cephalothin. Among the 1,467 enterococci isolated from the samples, E. faecalis (46.1%) and E. faecium (29.0%) were found to be the predominant species. Other enterococcal species made up 25% of the isolates. More than 96 and 97% of the E. faecalis and E. faecium isolates, respectively, were found to be resistant to ampicillin. Almost 34, 27.3, and 22.4% of the E. faecalis isolates from milk, beef, and chicken, respectively, were also resistant to cephalothin. The percentages of E. faecium isolates that were found to be resistant to cephalothin were 32.8, 16.9, and 17.3% for milk, beef, and chicken, respectively. Resistance to vancomycin was widespread. It was found that 18.8, 7.8. and 13.1% of the E. faecalis isolates from milk, beef, and chicken samples, respectively, were resistant to vancomycin. In contrast, 32.8, 24.7, and 30.7% of the E. faecium isolates from milk, beef, and chicken samples, respectively, were resistant to vancomycin. Isolates that were resistant to multiple drugs were found in relatively large numbers.     

Book reviews

Nutritional Toxicology. F. N. Kotsonis, M. Mackey, and J. J. Hjelle (eds.). Raven Press, New York, 1994, 331 pages, $135, ISBN 0–7817–0121‐X.

Bioprocess Production of Flavor, Fragrance, and Color Ingredients. Alan Gableman (ed.). Wiley and Sons, New York, 1994, 350 pages, $64.95, ISBN 0–471–03921–0. Available at local bookstores or call 1–800‐CALL‐WILEY.

Thermally Generated Flavors: Maillard, Microwave, and Extrusion Processes. Thomas H. Parliment, Michael J. Morello, and Robert J. McGorrin (eds.). ACS Symposium Series No. 543, American Chemical Society, Washington, DC, 1994, 494 pages, $109.95. Developed from a symposium sponsored by the Division of Agricultural and Food Chemistry at the 204th National Meeting of the American Chemical Society, Washington, DC, August 23–28, 1992.     

Protein,Fiber, and Mineral Nutrition of Growing Dairy Goats

Seven yearling Alpine does were in a series of balance trials to determine apparent utilization of fiber, protein, and minerals. The 34 kg does consumed 2.2% body weight of a hay-concentrate ration that was 18.8% crude protein, 40.9% neutral detergent fiber, 24.7% acid detergent fiber, 1.18% calcium, .67% phosphorus, .39% magnesium, .98% potassium, and .48% sodium. Digestion coefficients were 59.5, 68.5, 42.3, 70.6, and 29.3 for dry matter, crude protein, neutral detergent fiber, hemicellulose, and acid detergent fiber. Retention (g/day) was: 2.6, 1.3, 2.1, 1.8, and 1.1 for calcium, phosphorus, potassium, sodium, and magnesium. Nitrogen intake was related in a positive linear fashion to fecal nitrogen, urinary nitrogen, and absorbed nitrogen. Apparent absorption rates were 2.7, 1.4, 1.3, 5.1, and 3.2 g per doe per day for calcium, phosphorus, magnesium, potassium, and sodium. Mineral retentions as percent of grams apparently absorbed were 96.2, 88.2, 80.9, 37.7, and 56.0.     

啤特果营养成分的分析评价

对啤特果的氨基酸、矿质元素、挥发性物质及其他营养成分进行了分析测定,并进行了营养评价。结果表明,啤特果中水分、灰分、粗脂肪、蛋白质、总糖、总酸、粗纤维、可溶性固形物含量分别为88.2%、3.3%、0.82%、0.38%、6.47%、1.05%、3.05%和13.8%;每100 g样品中维生素C、维生素B1、B2、B6和胡萝卜素含量分别为2.2 mg、0.001 mg、0.139 mg、6.8 mg和0.042 mg;含有18种氨基酸,其总量（TAA）达到2658 mg/kg。EAA/TAA为37.02%,EAA/NEAA为58.78%,必需氨基酸种类齐全比例均衡,第一限制氨基酸为赖氨酸,氨基酸比值系数分(SRC)为62.0;K、Ca、P、Mg、Na、Fe、Zn、Cu、Mn矿质元素的含量分别为768.32、101.64、98.78、85.14、40.62、36.92、1.38、0.84、0.37 mg/kg;挥发性组分共分离25种物质,其中主要成分为己醛、乙酸乙酯、乙酸丁酯、丙酸乙酯、丁酸甲酯和2-丁烯酸乙酯,其相对含量分别为3.981%、0.215 %、0.187%、0.132 %、0.103%和0.137%。由此表明啤特果营养成分含量丰富,具有很好的开发与利用价值。     

BOOK REVIEWS

Book Reviews in this article.
Industrial Microbiology , Brinton M. Miller and Warren Litsky, Editors.
Practical Electron Microscopy for Biologists , 2nd Edition, Geoffrey A. Meek.
Plant Biochemistry , 3rd Edition, James Bonner and Joseph E. Varner, Editors.
Phenolic, Sulfur and Nitrogen Compounds in Food Flavors George Charalambous and Ira Katz, Editors.
Microbial and Plant Protoplasts , J. F. Peberdy, A. H. Rose, H. J. Rogers and E. C. Cocking, Editors.
The Enzyme Molecule , W. Ferdinand, Editor.
Enzymes in Food and Beverage processing , Robert L. Ory and Allen J. St. Angelo.
Biochemistry of Foods and the Biocatalysts , I. I. Shahied.
Enzyme Kinetics–The Steady State Approach , Paul C. Engel.     

田菁的开发与利用——田肉粉的化学成分(1)

研究了田菁种子炼胶后的副产物田肉粉的化学成分。结果表明田肉粉含有生物碱、皂甙、黄酮类、酚类和鞣质、有机酸、香豆素和萜类内脂化合物、糖类等,不含有强心甙、蒽醌类、氰甙,其中生物碱、皂甙、黄酮类、鞣质的含量分别为1.64%、2.28%,0.40%,1.86%.结合田肉粉的化学成分,对其生物活性进行了简要评述。     

Kinetics of amino acid extraction by lactating mammary glands in control and sometribove-treated Holstein cows.

Studies of mammary arteriovenous difference were conducted on multiparous lactating Holstein cows (n = 21) on d 35, 70, 105, and 126 of lactation to examine kinetic relationships between arterial concentration and mammary gland extraction of AA. Additionally, these cows were paired by previous lactational performance and assigned to bST-treated or control groups to examine the effect of bST treatment on AA concentration and extraction by lactating mammary glands. Treated cows were injected daily with 40 mg of recombinant bST from d 71 through 126 of lactation. Arterial concentrations of Asp, Ser, Asn, Gly, beta-aminoisobutyrate, and Met were increased. Concentrations of Val, Ile, Leu, Phe, Orn, and Lys were decreased in bST-treated cows compared with controls. Increased extractions of Asp and Met by mammary glands in treated versus control cows were correlated positively with treatment-induced changes in arterial concentrations of these AA. However, increased mammary extractions of Arg, cystathionine, Leu, and Lys by bST-treated compared with control cows were not correlated with bST-induced changes in arterial concentrations of these AA. Extractions of Asn, His, Thr, Arg, Tyr, Met, cystathionine, cystine, Ile, Phe, Orn, Glu, Gly, Tau, Cit, Leu, and Val were correlated linearly with arterial concentrations (r2 greater than .15) of each AA. Extractions of Asp, Glu, Ser, Asn, Gly, Gln, Tau, His, Cit, Thr, Pro, Tyr, Val, cystine, Ile, Leu, Trp, Orn, and Lys also were correlated with arteriovenous differences of Met.     

Book Review

Book Reviews in this article. Food Chemistry , second edition, revised and expanded, Edited by Owen R. Fennema. Immunoassays in Food Analysis. Edited by B. A. Morris and M. N. Clifford. Topics in Flavour Research, Proceedings of the International Conference Frehing-Wehenstephen, April 1-2,1985 , R. G. Berger, s. Nitz, and P. Schreier. Biotechnology for the Oils and Fats Industry , C. Ratledge, P. Dawson, and J. Rattray, Eds. Advances in the Microbiology and Biochemistry of Cheese and Fermented Milk , Edited by F. Lyndon Davies and Barry A. Law. Amino Acids and Peptides , Edited by J. S. Davies. Oxygen Radicals in Biologicial Systems , Vol. 105, Methods in Enzymology. Edited by Lester Packer. The Elements of Graphing Data , William S. Cleveland.