Research Publications (Food Safety)

The prevalence of multidrug-resistant Pseudomonas aeruginosa has led to the reexamination of older "forgotten" drugs, such as temocillin, for their ability to combat resistant microbes. Temocillin is the 6-α-methoxy analogue of ticarcillin, a carboxypenicillin with well-characterized antipseudomonal properties. The α-methoxy modification confers resistance to serine β-lactamases, yet temocillin is ineffective against P. aeruginosa growth.

Manogepix (MGX) targets the conserved fungal Gwt1 enzyme required for acylation of inositol early in the glycosylphosphatidylinositol biosynthesis pathway. The prodrug fosmanogepix is currently in clinical development for the treatment of invasive fungal infections. We determined that the median frequencies of spontaneous mutations conferring reduced susceptibility to MGX in Candida albicans, C. glabrata, and C. parapsilosis ranged from 3 x 10–8 to <1.85 x 10–8.

In this study, a preliminary food quality and safety assessment was performed on organic and cage-free egg samples marketed in the state of Rio de Janeiro, Brazil, that were analyzed concerning veterinary drug and pesticide residues using high performance and ultra performance liquid chromatography coupled to tandem mass spectrometry.

This study aimed to evaluate the performance of polyphenolic extraction from leaves of Eugenia uniflora by using solvent systems and different extractive conditions. The solvent systems containing water, methanol, ethanol, and acetone (binary, ternary, or quaternary mixtures) were used to produce extracts by turbo-extraction in accordance with a simplex centroid.

Author(s): Zhao Bin Li, Peng Lei Cui, Jing Liu, Ju Xiang Liu, Jian Ping Wang

United States dairy operations use antibiotics (primarily β-lactams and tetracyclines) to manage bacterial diseases in dairy cattle. Antibiotic residues, antibiotic-resistant bacteria (ARB), and antibiotic resistance genes (ARG) can be found in dairy manure and may contribute to the spread of antibiotic resistance (AR). Although β-lactam residues are rarely detected in dairy manure, tetracycline residues are common and perhaps persistent.

Author(s): Sihang Zhu, Jingjing Zhao, Nan Zhao, Xiao Yang, Chong Chen, Jianying Shang

Aminopeptidase N is an important metalloenzyme from the M1 zinc metallopeptidase family, which is present in numerous apicomplexan parasites, including Plasmodium, Eimeria, and Cryptosporidium. Aminopeptidase N is a potential drug target, and hence, its properties have been widely investigated. In the current study, the cellular localization and enzyme characteristics of Toxoplasma gondii aminopeptidase N3 (TgAPN3) were evaluated in vitro.

Lipopeptides are important non-ribosomal peptide synthetases (NRPSs) products with broad therapeutic potential in biotechnology and biopharmaceutical applications. Fatty acyl modifications in N-terminal of lipopeptides have attracted wide interest in the engineering processes of altered fatty acyl selectivity.

Author(s): Antoine Rostang, Jacques Devos, Christophe Chartier

Multidrug efflux pumps play an important role in antibiotic resistance in bacteria. In Pseudomonas aeruginosa, the MexXY pump provides intrinsic resistance to many antimicrobials, including aminoglycosides. The expression of the mexXY operon is negatively regulated by the MexZ repressor. This repression is alleviated in response to antibiotic-induced ribosome stress, which results in increased synthesis of the antirepressor ArmZ, interacting with MexZ.

ABSTRACT The poultry industry has recently undergone transitions into antibiotic free production, and viable antibiotic alternatives, such as probiotics, are necessary. Through in ovo probiotic inoculation, beneficial microflora development in the gastrointestinal tract may occur prior to hatch without negatively impacting chick performance.

It has been reported that Heteropodatoxin3 (HpTx3), a peptidic neurotoxin purified from the venom of the spider species Heteropoda venatoria, could inhibit Kv4.2 channels. Our present study newly found that HpTx3 also has potent and selective inhibitory action on Nav1.7, with an IC50 of 135.61 &plusmn; 12.98 nM.

Author(s): Bian-hua Zhou, Liu-shu Jia, Hong-wei Guo, Hai-yan Ding, Jing-yun Yang, Hong-wei Wang

by Yutaka Takaoka, Atsuko Takeuchi, Aki Sugano, Kenji Miura, Mika Ohta, Takashi Suzuki, Daisuke Kobayashi, Takuji Kimura, Juichi Sato, Nobutaro Ban, Hisahide Nishio, Toshiyuki Sakaeda

A method based on micellar liquid chromatography was developed to determine oxolinic acid, ciprofloxacin, enrofloxacin, and sarafloxacin in eggs and egg products. The antimicrobial drugs were obtained in a micellar solution which was directly injected. The analytes were resolved using a C18 column and a mobile phase of 0.05 M sodium dodecyl sulfate—7.5% 1-propanol—0.5% triethylamine, buffered at pH 3 with phosphate salt, running under the isocratic mode.

by Marlene Belmar, Sharif Aly, Betsy M. Karle, Richard V. Pereira

Author(s): P. Quintanilla, M. Cornacchini, M.I. Hernando, M.P. Molina, I. Escriche

Flumequine (FLU) is widely used as an antibiotic in the treatment and control of animal diseases, which may result in the presence of residues harmful to humans in food products of animal origin. A novel and fast biomimetic enzyme-linked immunosorbent assay (BELISA) was developed for the determination of FLU based on a molecularly imprinted polymer (MIP) as a selective affinity agent.

Galactosaminogalactan (GAG) is an insoluble aminosugar polymer produced by Aspergillus fumigatus and has anti-inflammatory properties. Here, the minimum glycosidic sequences required for the induction of IL-1Ra by peripheral blood mononuclear cells (PBMCs) was investigated. Using chemical degradation of native GAG to isolate soluble oligomers, we have found that the de-N-acetylation of galactosamine residues and the size of oligomer are critical for the in vitro immune response.

ABSTRACT BACKGROUND The low cost of aminoglycoside (AMG) antibiotics facilitates their excessive use in animal husbandry and agriculture sector. This scenario has led to the occurrence of residues in the food chain. After several years of AMGs use in antibacterial therapy, resistance to streptomycin has begun to appear. The method lacks AMG specificity previously reported against a single antibiotic and described as selective.

The present study was envisaged with an aim to determine the occurrence of antibiotic residues; enrofloxacin, oxytetracycline, penicillin G, sulphamethoxazole and chloramphenicol as well as mycotoxins; aflatoxin M1 and ochratoxin A in raw milk samples collected from individual animals from dairy farms located in 9 districts of Punjab, India. A total of 168 raw milk samples were collected and analysed using commercially available competitive Enzyme linked immunosorbent assay kits.

Author(s): Johanne Ellis-Iversen, Anne Mette Seyfarth, Helle Korsgaard, Valeria Bortolaia, Nanna Munck, Anders Dalsgaard

ABSTRACT

Potential synergism between florfenicol (FF) and thiamphenicol (TAP) was investigated for in vitro efficacy against Actinobacillus pleuropneumoniae and/or Pasteurella multocida as well as in vivo efficacy in swine. Among isolates of A. pleuropneumoniae (n = 58) and P. multocida (n = 79) from pigs in Taiwan that were tested, high percentages showed resistance to FF (52 and 53%, respectively) and TAP (57 and 53%, respectively).