从自由基生物学角度评价鸡肉质量的实验研究

本文把外观健康和非健康的活鸡各20只分成两组,宰后测其肝、腿肌中超氧化物歧化酶(SOD)含量和脂质过氧化产物丙二醛(MDA)水平,发现两组中上述指标值差异显著(P<0.050 ;同时对两组实验鸡胴体在宰后4小时做了感官鉴别,也判断出其品质存在差异。提示体内SOD活性和MDA水平可以反映鸡肉质量,比感官鉴别更具敏感性,同时也可以反映宰前鸡的健康状况。     

谷朊粉废水提取物在肉制品中的应用

介绍了一种从谷朊粉废水中提取戊聚糖的工艺,由此工艺得到的产品(戊聚糖质量分数约70%,蛋白质质量分数约20%)能较好地保持戊聚糖的特性.研究了其它添加剂(卡拉胶)对戊聚糖的乳化性,戊聚糖对肉制品持油、持水性以及其质构的影响.谷朊粉废弃水提取物与卡拉胶的复配产品在添加量(质量分数)为6%时能使肉制品有较好的持油性和相应的质构.     

几种谷物,鱼肉及贝肉中DNA含量测定

核酸是遗传的物质基础。近年来的某些研究表明，外源核酸在促进和改善大脑，骨髓，肠粘膜及血细胞等组织器官的代及功能活动上具有重要作用。本文采用经典的紫外分光光度法对几种谷物和几种鱼肉及贝肉中的ＤＮＡ含量进行了测定，为外源核酸的材料选择提供了参考。     

Ovine scrapie: Follow-up of sheep belonging to an endemic scrapie-infected flock

There is a close similarity between the unconventional virus-induced ovine scrapie and human Creutzfeldt-Jakob disease. Since infection might be transmitted orally, the ovine production of an endemically scrapie-infected farm was studied. About 80% of the annual production are sold (50% as butcher-meat, 30% as breeding animals), and scrapie appears in 20% of the sheep kept on the farm. Was the same proportion of butcher-meat animals scrapie-infected? Since the scrapie agent has been detected in “clinically normal” lambs, the same problem occurs with breeding-sheep and “apparently healthy” animals: are they carriers of the pathogenic agent? Are they responsible for the spread of the ovine disease and/or of the human disease?     

Identification of bovine IgG as a major cross-reactive vertebrate meat allergen

BACKGROUND: Although beef is a main source of protein in Western diets, very little has been published on allergic reactions to beef or the main allergens implicated in these reactions. The aim was to evaluate the IgE antibody response to beef in suspected meat-allergic subjects and assess cross-reactivity of beef with other vertebrate meats. METHODS: Fifty-seven sera from suspected meat-allergic subjects were tested by grid blot for specific IgE antibodies to vertebrate meats (beef, lamb, pork, venison, and chicken), and the patterns of recognition of meat proteins were assessed by immunoblot studies. RESULTS: A 160-kDa band, identified as bovine IgG, was detected in raw beef in 83% (10/12) of beef-allergic subjects but in only 24% of the beef-tolerant subjects. IgE reactivity to a band of similar mol. mass was detected also in lamb and venison, but rarely in pork or chicken. Complete inhibition of the IgE reactivity to the bovine IgG was obtained with lamb, venison, and milk. IgE reactivity to this band also completely disappeared when beef or lamb extracts were separated under reducing conditions, indicating conformational epitopes. CONCLUSIONS: Bovine IgG appears to be a major cross-reacting meat allergen that could predict beef allergy. Further studies with oral IgG challenges should be performed to document the conclusion that in vitro reactivity correlates with clinical hypersensitivity. The role of bovine IgG in other bovine products such as milk, dander, or hair must also be studied, and the hypothesis that it is a cross-reacting allergen with other mammalian products validated.     

Dexamethasone and clenbuterol detection by enzyme immunoassay in Bovine Liver Tissue: A new multiresidue extraction procedure

A fast and simple extraction procedure was developed for simultaneous determination in bovine liver of two veterinary drugs, widely used as growth promoters in meat production: dexamethasone (a synthetic corticosteroid drug) and clenbuterol (a beta2‐adrenergic agonist drug). Liver samples were extracted by acetonitrile, without any clean‐up step. Two different ELISAs, specific for the two classes of drugs, were used to determine the residue concentration in the extracts. The intra‐ and inter‐extraction variability was determined at different concentrations: the intra‐extraction coefficients of variation (CVs) were between 2.5 and 17.7% for dexamethasone and between 0.9 and 9.8% for clenbuterol; the inter‐extraction CVs were between 2.0 and 16.8% for dexamethasone and between 0.5 and 10.8% for clenbuterol. Recovery ranged from 92 to 154% for dexamethasone and from 78 to 105% for clenbuterol. The limit of detection was 1.43 ng g^?1 and 0.43 ng g^?1, respectively. The limit of quantification for dexamethasone was 2.09 ng g^?1 and for clenbuterol was 0.72 ng g^?1. The combination of the new extraction procedure with an ELISA detection permitted the rapid semi‐quantitative determination of both dexamethasone at its maximum residue level (MRL: 2.5 ng g^?1 in liver tissue), and clenbuterol at low concentration level.     

Dietary Factors and Prostate Cancer Development,Progression, and Reduction

Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer.     

How Do Consumers Perceive Cultured Meat in Croatia,Greece, and Spain?

The meat production industry is one of the leading contributors of greenhouse gas emissions. Cultured meat presents itself as a potential eco- and animal-friendly meat substitute which has the potential to eradicate animal cruelty and reduce both the environmental footprint and the risk of zoonotic illnesses, while delivering a nutrient-dense product. The purpose of this study was to investigate how consumers perceive cultured meat and if the frequency of meat consumption is related to their intention of trying or purchasing cultured meat. Data were collected online in 2020 from Croatia, Greece, and Spain. Among the 2007 respondents, three segments were identified according to meat consumption and variety, plus an a priori identified group of “non-meat eaters”. Sixty percent perceived cultured meat as kind to animals, 57% as unnatural, 45% as healthy and environmentally-friendly, 21% as disgusting, and only 16% as tasty. Although 47% of the respondents had not heard of cultured meat before, 47% would taste it and 41% would purchase it for the same price as conventional meat. This indicates that consumers from Croatia, Greece and Spain might be likely to purchase cultured meat if sold at an affordable price.     

2017年成都地区孕妇孕早中期红肉摄入及其对妊娠期糖尿病影响的前瞻性研究

目的了解成都地区孕妇孕早、中期红肉摄入现状,探讨孕早、中期红肉摄入量对妊娠期糖尿病(gestational diabetes mellitus,GDM)的影响。方法采用前瞻性研究,于2017年2—7月通过立意抽样方法选取成都市某三甲妇幼医疗机构产前门诊孕8~14周单胎健康孕妇为研究对象,于纳入时通过问卷调查收集孕妇的年龄、孕前体重、孕次等基本信息。采用3天24小时膳食回顾法分别于纳入时、孕24~28周收集孕妇孕早、中期摄入的所有食物种类及数量,计算平均每日肉类、红肉摄入量及其来源构成。于孕24~28周行75 g口服葡萄糖耐量试验,根据《中国妊娠合并糖尿病诊治指南(2014)》诊断GDM。将红肉摄入量按三分位法分为低、中、高三个水平组,以低水平组为参照,采用多因素非条件Logistic回归分析孕早、中期红肉摄入与GDM的关系。结果最终纳入有效样本985例。孕妇孕早期和孕中期肉类总摄入量分别为70.7和102.9 g/d,红肉平均摄入量分别为52.0和74.6 g/d,红肉占肉类总摄入量的比例分别为73.6%和72.5%。控制年龄、孕前体质指数、糖尿病家族史及能量摄入量等混杂因素后,多因素非条件Logistic回归分析结果显示:孕中期红肉摄入高水平组(>86 g/d)较低水平组(<44 g/d)GDM发生风险增加(OR=1.499,95%CI 1.028~2.185);未观察到孕早期红肉摄入量对GDM发生风险有影响(OR=1.029,95%CI 0.716~1.481)。结论成都地区孕妇孕中期红肉摄入较多,孕中期红肉摄入大于86 g/d可能增加GDM的发生风险。     

Assessment of oestrogenic potency of chemicals used as growth promoter by in-vitro methods

Three in-vitro bioassays were used to compare the oestrogenic potency of chemicals used as growth promoter in beef cattle in certain non-European Union countries (17beta-oestradiol, alpha-zearalanol, testosterone, trenbolone, trenbolone acetate, melengestrol acetate) or found as food contaminant such as the mycotoxin zearalenone and some of their metabolites (17alpha-oestradiol, oestrone, 17alpha-epitestosterone, 19-nortestosterone, androstendione, zearalanone, alpha-zearalanol, beta-zearalanol, alpha-zearalenol, beta-zearalenol). The strong oestrogens 17alpha-ethinyl oestradiol and diethylstilboestrol were used as standards. The first bioassay was based on the activation of a reporter gene by oestrogens in recombinant yeast expressing human or rainbow trout oestrogen receptor. In the second bioassay, the vitellogenin gene induction of rainbow trout hepatocyte cultures was used as a biomarker for the exposure to oestrogens. The third bioassay was based on the alkaline phosphatase gene induction by oestrogens in the human endometrial Ishikawa cell line. The assessment of oestrogenic potency of these chemicals clearly demonstrates the strong oestrogenicity of the mycotoxin zearalenone and its metabolites and particularly alpha-zearalenol which was as potent as ethinyl oestradiol and diethylstilboestrol in the human endometrial Ishikawa cell line.