生物杀菌素在食品防腐中的应用研究进展

文章阐述了生物杀菌素的特点及在食品防腐中的应用研究概况，并对生物杀菌素的发展趋势进行了展望。     

Trends in somatic cell counts,bacterial counts,and antibiotic residue violations in New York State during 1999-2000

Milk quality data on a month-by-month basis from March 1999 to December 2000 were studied from five of the largest milk plants operating in New York State. The analyses focused on bulk tank somatic cell count (SCC), bacterial counts in the form of plate loop count (PLC), and antibiotic residue violations in the pool of milk of New York State, their mutual relation, and the influence of farm size. The average SCC was 363,000 cells/ml, the average PLC was 24,400 bacteria/ml, and the average number of antibiotic residue violations in the pool of milk was 3.9 per 1000 producers. Each month between 72 and 88% of the milk pool had SCC levels in compliance with the European Union (EU) requirements (SCC < 400,000 cells/ml). The findings in this study suggest that larger farms had lower SCC and PLC but more antibiotic violations. However, the larger farms contribute most to the SCC and PLC of the total pool of milk. Farms with high SCC also had higher PLC and more antibiotic violations. Measurable improvements in overall quality of the pool of milk in New York state would most likely occur by targeting incentives, education, and training programs for any farms with very high SCC and for larger farms with SCC between 400,000 and 750,000 cells/ml.     

乳及乳制品中抗生素类兽药残留快速检测技术

抗生素等兽药残留物分析是个十分复杂的技术问题，介绍了按不同目的和要求对抗生素等兽药残留物进行的分级检测的策略，并对目前国内外正在应用或开发的快速检测技术进行了介绍。     

Species Diversity and Pheno‐ and Genotypic Antibiotic Resistance Patterns of Staphylococci Isolated from Retail Ground Meats

The presence and species diversity of staphylococci in 250 ground beef and lamb meat samples obtained from Diyarbakir, Turkey were investigated. The presence of the 16S rRNA gene, mecA, nuc, pvl, and femA was analyzed by multiplex PCR. Pheno‐ and genotypic antibiotic resistance profiles of 208 staphylococci isolates were established. Of the ground beef and ground lamb samples, 86.4% and 62.4% were positive for staphylococci, respectively. Staphylococcus aureus, S. saprophyticus, S. hominis, S. lentus, S. pasteuri, S. warneri, S. intermedius, and S. vitulinus made up 40.8%, 28.8%, 11%, 3.8%, 3.8%, 2.4%, 2.4%, and 2.4% of isolates, respectively. Of the 85 S. aureus isolates, 40%, 47%, and 5.8% carried femA, mecA, and pvl, respectively, whereas the corresponding rates for the 118 coagulase‐negative staphylococci (CoNS) were 0%, 10.1%, and 0%, respectively. We determined from the 208 isolates, the highest antibiotic resistances were to tetracycline and oxytetracycline (85.5%), followed by penicillin (51.4%), novobiocin (45.6%), ampicillin (39.9%), and doxycycline (31.7%), using the Clinical and Laboratory Standards Inst. (CLSI) method. All isolates were sensitive to gentamycin, ofloxacin, and tobramycin, but 2.3% of the S. aureus isolates had resistance to vancomycin. The staphylococci isolates carried tet(K), blaZ, tet(L), tet(W), cat, tet(S), tet(M), ermB, ermA, and ermC antibiotic resistance genes at rates of 59%, 51.7%, 36.9%, 31.8%, 27.2%, 27.2%, 24.4%, 18.1%, 7.9%, and 3.9%, respectively.     

抗生素含量测定方法在《中国药典》2010年版中的应用比较

文章主要结合《中华人民共和国药典》2010年版中收载的348个抗生素品种,对抗生素含量测定的方法进行了统计分析,其中有247个品种采用高效液相色谱法,86个品种采用微生物检定法,3个品种采用滴定分析法,12个品种采用紫外分光光度法。     

Antibiotic residues in milk from small dairy farms in rural Peru

The use of antibiotics in livestock can pose a public health threat, especially if antibiotic residues remain in the food product. Understanding how often and why farmers sell products with antibiotic residues is critical to improving the quality of these products. To understand how often milk with antibiotic residues is sold on small farms in a major dairy-producing region of Peru and identify factors associated with selling milk with antibiotic residues, we tested milk samples for antibiotic residues from every provider on three routes of commercial milk companies and from bulk tanks of farmers currently treating cows with antibiotics. We also asked farmers if they sold milk from treated cows and examined factors associated with the tendency to do so. The prevalence of milk contamination with antibiotic residues on commercial routes was low (0–4.2%); however, 33/36 farmers treating their animals with antibiotics sold milk that tested positive for antibiotic residues. The self-reported sale of milk from treated cows had a sensitivity, specificity, and positive and negative predictive values of 75.8%, 100%, 100% and 27.2%, respectively (with testing of milk for residues as the gold standard). Finally, 69/156 randomly selected farmers reported selling milk from treated cows, and farmers’ knowledge of antibiotics and the milk purchaser were significantly associated with a farmer’s tendency to report doing so. Educating farmers on the risks associated with antibiotics and enforcement of penalties for selling contaminated milk by milk companies are needed to improve milk quality.     

Multiplex immunoassay based on biochip technology for the screening of antibiotic residues in milk: validation according to the European guideline

ABSTRACT

The Infiniplex for milk® (IPM) kit is a quick method for the simultaneous and qualitative detection of more than 100 molecules including antibiotic residues, mycotoxins, anti-inflammatories and antiparasitic drugs into a single test that does not require milk treatment.

The IPM® kit was validated according to the European decision EC/2002/657 and according to the European guideline for the validation of screening methods (2010). Our validation was focused only on antibiotic residues. The washing step was identified as the most critical step of the assay. Insufficient washes could cause a significant background noise that prevents imaging. Positive controls have to be freshly prepared each day (insufficient stability).

The method was specific with a low false-positive rate of 1.7% on 5 discrete test regions (DTR) ((beta-lactams, lincomycin, virginiamycin, quinolones and sulphonamides)) and a false-positive rate of 0% on the 26 other DTR. During our validation, the 42 determined detection capabilities CCβ for 12 antibiotic families (aminoglycosides, cephalosporins, lincosamides, macrolides, miscellaneous antibiotics, penicillins, phenolated polymixins, polypeptide antibiotics, quinolones, sulphonamides, tetracyclines) were at between once and twice the decision levels stated by the manufacturer. Forty CCβ determined were lower than the respective regulatory limits (i.e. MRL, RC, MRPL) in milk, except for tilmicosin (1.5 times the MRL) and neospiramycin (>1.25 times the MRL). The estimated CCβ of thiamphenicol, cloxacillin, danofloxacin, sulphathiazol, ceftiofur and sulphamonomethoxine were lower than or at the MRL. However, it was difficult to approach an accurate CCβ with only qualitative results. It is impossible to know whether or not we were close to the cut-off value. The software could be improved by differentiating between low-positive and high-positive results. The results of our participation in three qualitative proficiency tests in 2016 and 2017 for the detection of quinolones, tetracyclines and sulphonamides in cows’ milk were very satisfactory.     

我国食源性蜡样芽孢杆菌毒力基因和药物敏感性研究

目的 了解我国不同地区食源性蜡样芽孢杆菌的毒力基因携带特点及其对抗生素的敏感性,为食源性食物中毒的防治提供参考依据.方法 采用PCR方法对2011年我国不同地区收集的238株食源性蜡样芽孢杆菌10种毒力基因进行检测;采用微量肉汤稀释法测定其抗生素敏感性.结果 溶血素BL基因、肠毒素T基因和细孢毒素K基因是我国食源性蜡样芽孢杆菌的主要毒力基因,至少携带一个毒力基因的菌株达到检出菌总数的87.4％;蜡样芽孢杆菌对庆大霉素、万古霉素、环丙沙星、复方新诺明的敏感率为100％,对红霉素、四环素、氯霉素、克林霉素的敏感率分别为88.8％、90.2％、99.6％、87.1％,对氨苄西林和头孢噻肟的敏感率仅为0.4％和5.4％.结论 我国食源性蜡样芽孢杆菌毒力基因携带率较高,对食品安全和公共健康构成潜在的威胁;蜡样芽孢杆菌对氨苄西林、头孢噻肟的敏感性差,不应作为经验用药和预防用药.     

红霉素类抗生素电喷雾/飞行时间质谱源内CID研究

本文采用电喷雾 /飞行时间质谱法 ,对 5个红霉素类抗生素进行了源内CID研究 ,并以PEG40 0及各样品质子化分子离子 (MH+ )做为内标物 ,对碎片离子进行了准确质量测定 ,确认了这些碎片离子 ,并总结了此类化合物的裂解规律。样品分子含有去氧氨基糖 (desosamine)或红霉糖 (cladinose)两个糖基片段 ,其中去氧氨基糖易于形成带电离子。另外考察了喷管电压 (NozzlePotential)、溶剂条件等对红霉素类抗生素电喷雾源内CID质谱的影响。     

膜分离技术在抗生素提炼过程中的应用

膜分离过程是一种选择性高,操作简单,能耗低的纯物理分离技术,已在各工业领域和科学研究中得到广泛的应用,文章对膜分离技术在抗生素提炼领域的技术进展进行了较全面的综述。