Abstract
Background
Veterinary drugs are widely used in animals to prevent diseases and are a complex set of drugs with very different chemical properties. Multiclass and multi-residue methods for ...simultaneous detection of residues from veterinary drugs and contaminants in urine are very rare or non-existent. Therefore, the aim of this study was to develop and validate a sensitive and reliable quantitative LC-MS/MS method for simultaneous determination of a wide range of veterinary drug and pesticide residues and mycotoxins in bovine urine. This involved 42 veterinary drug residues (4 thyreostats, 6 anabolic hormones, 2 lactones, 10 beta agonists, 15 antibiotics, 5 sulphonamides), 28 pesticides and 2 mycotoxins. Stable isotopically labelled internal standards were used to facilitate effective quantification of the analytes. Analysis was performed in both positive and negative ionization modes with multiple reaction monitoring transitions over a period of 12 min.
Results
The parameters validated included linearity, limit of detection (LOD), limit of quantification (LOQ), detection capability (CCβ), decision limit (CCα), stability, accuracy and precision. The process followed guidelines of the regulation 2021/808/EC. The calibration curves were linear with coefficient of correlation (R
2
) from 0.991 to 0.999. The LODs were from 0.01 to 2.71 µg/L, while the LOQs were from 0.05 to 7.52 µg/L. The CCα and CCβ were in range 0.05–12.11 µg/L and 0.08–15.16 µg/L. In addition, the average recoveries of the spiked urine samples were from 71.0 to 117.0% and coefficient of variation (CV) < 21.38% (intraday and interday).
Conclusion
A new isotopic LC-MS/MS method has been developed, validated and applied for identification and quantification of 72 residues of veterinary drugs and pesticides and other contaminants such as mycotoxins in bovine urine. The most appropriated sample preparation procedures involved sodium acetate buffer, enzymatic hydrolysis using β-glucuronidase and cleanup solid phase extraction with OASIS SPE cartridges. The parameters were satisfactorily validated fulfilling requirements under Regulation 2021/808/EC. Consequently, the method could be used in routine analysis of bovine urine samples for simultaneous detection of veterinary drug and pesticide residues as well as contaminants such as mycotoxins.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Due to the actuality of spongiform encephalopathies and their proven spreading by means of animal feed containing meat and bone meal, the description and measurement of osteocytic lacunae contributes ...to more easily distinguish bone fragments in meat and bone meal. Transmissible spongiform encephalopathies (TSEs) have attracted a lot of attention, especially after 1986, when the first case of BSE (bovine spongiform encephalopathy) was detected. Since the outbreak of spongiform encephalopathy (BSE), the use of animal protein including bone meal as an ingredient in animal feed has been controlled by several regulations including Regulation (EC) 999/2001, Regulation (EC) 1774/2002, and Regulation (EC) 1234/2003. The classical microscopic method is the only official method for detecting animal protein in animal feed in the European Union (Commission Regulation (EC) 152/2009). By applying the microscopic method to the animal feed samples, we performed detection in order to determine the presence of animal proteins that originate from mammals and fish. The microscopic analysis of all 421 samples, of which 115 were raw materials for the production of animal feed, 230 were concentrates for ruminant nutrition and 76 were concentrates for non-ruminant nutrition (32 concentrates for laying hens and 44 concentrates for pigs), did not provide positive results, that is, no remains of animal tissues of mammalian origin were found in any specimen. Whereas in 10 out of 32 (31.25%) concentrates intended for non-ruminant nutrition (laying hens), pieces of fish tissue were found. In these samples, we usually detected the presence of fish bones, gills and scales.
Wheat is one of the world’s most commonly consumed cereal grains. It originates from a type of grass (Triticum) that is grown in countless varieties worldwide. Bread wheat or common wheat is a ...primary species. Several other closely related species include durum, spelt, emmer, einkorn, and Khorasan wheat. In addition to being a major source of starch and energy, wheat also provides substantial amounts of a number of components which are essential or beneficial for health, notably proteins, vitamins (notably B vitamins), dietary fibres, and phytochemicals. Wheat is a basic food product of Macedonian population. This study is mainly focused on measuring the concentration of radioactivity due to natural radioactive nuclides (226Ra, 232Th, 40K) in wheat grain samples, as well as on determining the quality of wheat used in daily diet. In addition, in this study we calculated radiation hazard indices (radium equivalent activity and internal hazard index) in the wheat sample. Average activity concentrations of 226Ra, 232Th, and 40K in the wheat samples were 0.57±0.14; 0.39±0.11; 96.55±0.86 (Bq·kg-1), respectively. The radiation hazard indices were calculated for all samples in this study where mean values did not exceed safety limits, pointing out to negligible radiation hazard arising from terrestrial radionuclides that are naturally present in wheat. In terms of quality, we confirmed that all tested samples meet the requirements regarding quality in accordance with the laws in our country.
Analytical methods based on immunoaffinity column clean-up and quantitative determination with liquid chromatography-fluorescence detection were used to determine aflatoxins and ochratoxin A in liver ...samples. The validation of the procedures was performed. The linearity of the methods was checked, and a good coefficient of correlation was found for all aflatoxins and OTA as well. The LOD and LOQ were acceptable: 0.003 µg/kg and 0.009 µg/kg for AFB
; 0.001 µg/kg and 0.005 µg/kg for AFB
; 0.006 µg/kg and 0.020 µg/kg for AFG
; 0.007 µg/kg and 0.022 µg/kg for AFG
; 0.08 µg/kg and 0.27 µg/kg for OTA. The results for the repeatability estimated by the relative standard deviation (RSD
) were satisfactory and the obtained values were in the acceptable range (1.97–14.41% for all aflatoxins and 3.76-8.31% for OTA) at three proposed concentration levels. RSD
values showed acceptable correlation between two analysts for all four aflatoxins and OTA. The RSD
values were as followed: 2.37% and 5.60% for AFB1, 6.71% and 8.78% for AFB
, 4.40% and 7.00% for AFG
and 10.30% and 13.91% for AFG
(for the first and second analyst, respectively). The RSDR values for OTA were 4.91% and 3.15% (1 µg/kg); 3.76% and 4.12% (5 µg/kg) and 8.31% and 8.21% (10 µg/kg). The mean recovery for total aflatoxins and OTA were 78.10% and 93.34%, respectively. All validation parameters were in accordance to European legislation. They indicate that the proposed analytical procedures are suitable and they could be methods of choice for the determination of aflatoxins and OTA in liver samples.
Corn, wheat and other different types of cereal crops, are one of the basic nutritional products in general, which have essential and vast application in the daily diet of people around the world. ...Cereal crops are the most important food sources, and cereal-based food is the main source of energy, protein, B vitamins and minerals for the world population. Therefore, the goal of this research is to analyze the production of wheat on arable land in the Republic of North Macedonia, as an agricultural country, which will indirectly help to draw conclusions about the impact on the economic structure of the population, their standard of living, the investment and economic fluctuations in market prices, taken as a sui generis element, set as an assumption ceteris paribus against the other determinants and factors that affect the national economy in the Republic of North Macedonia.
Full text
Available for:
CEKLJ, NUK, ODKLJ, UL, UM, UPUK
A different, reliable, and cost-effective strategy for the analysis of aflatoxins, ochratoxin A, and zearalenone in corn-based foods was proposed, including one multi-toxin immunoaffinity column ...(IAC) sample preparation and three different high-performance liquid chromatography fluorescence detection methods. The analytical procedures were tested and verified, keeping in mind their occurrence at trace levels in corn-based foods. With the validation of the proposed multi-toxin IAC methodology and comparison of the performance characteristics with methods using a single-toxin IAC, we confirmed the reliability of the multi-toxin IAC procedure versus the single-toxin IAC. The methods were validated by revealing satisfactory performance characteristics; for example, the obtained values of limit of detection were significantly lower than the maximum limits for all mycotoxins of concern. In addition, the recovery values were between 70.9 % and 106.1 % for all mycotoxins of interest, with precision values lower than 10.5 %.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The care of radioactivity level in animal feed is very important, as ingestion is one of the most common ways radionuclides enter living organisms. Thus, since humans consume products of animal ...origin (eggs and poultry, milk and beef), it is important to monitor radiation levels in animal feed, as part of the radioactivity that these animals are exposed to, could be transmitted to humans. Natural radionuclides such as 40K, 232Th and 226Ra find their way into the food chain from soil and air to plants and from plants to animals and humans as well. The goal of this study was to determine the activity concentrations of natural radionuclides in three commercial chicken feeds – starter, grower and finisher. The analyzes were performed by means of HPGe gamma spectrometry - gamma spectrometer (Canberra Packard) with a high-purity germanium detector. The obtained spectra from the measurement were analyzed by using the program GENIE 2000. Based on the performed tests, the mean values for the activity concentrations in the samples were the following 26.03±4.1 Bq kg-1 for 226Ra, 37.9±4.8 Bq kg-1 for 232Th, and 64.40±6.5 Bq kg-1 for 40K. The results obtained from the analyses of chicken feeds were compared to studies in other countries and it was found that 40K was present in the highest amount in all types of samples while the vales for the other natural radionuclides were within the nominal concentrations. Higher concentration of 40K can be associated with plants used in the production of animal feed, which were contaminated with fertilizer during their cultivation. The range of radionuclide concentrations in the samples was within the recommended values UNSCEAR.
Praćenje razine radioaktivnosti u hrani za životinje od izrazite je važnosti, budući da je oralna konzumacija jedan od najčešćih načina unosa radionuklida u živuće organizme. S obzirom na ljudsku konzumaciju proizvoda životinjskog porijekla (jaja, perad, mlijeko i govedina), važno je pratiti razine radijacije u hrani za životinje budući da dio ukupne radioaktivnosti kojoj su životinje izložene može prijeći na ljude. Prirodni radionuklidi poput 40K, 232Th i 226Ra ulaze u hranidbeni lanac iz zemlje i zraka u biljke te u životinje i ljude. Cilj ovog istraživanja je odrediti aktivne koncentracije prirodnih radionuklida u tri komercijalne vrste hrane za piliće – starteru, groweru i finišeru. Analize su provedene uporabom gama spektrometra visoke rezolucije, odnosno gama spektrometrom (Canberra Packard) s germanijskim detektorom visoke čistoće. Dobiveni mjerni raspon analiziran je uporabom programa GENIE 2000. Temeljem izvedenih ispitivanja uzoraka, prosječne vrijednosti aktivnih koncentracija su 26.04±4.1 Bq kg-1 za radionuklid 226Ra, 37.9±4.8 Bq kg-1 za radionuklid 232Th i 64.40±6.5 Bq kg-1 za radionuklid 40K. Rezultati navedenih analiza hrane za piliće uspoređeni su s istraživanjima provedenim u drugim državama, a zaključak istog je da je radionuklid 40K prisutan u najvišim količinama u svim vrstama analiziranih uzoraka dok su zabilježene normalne koncentracije ostalih prirodnih radionuklida. Više koncentracije radionuklida 40K mogu se povezati s biljkama upotrjebljenima u proizvodnji hrane za životinje, a koje su prethodno bile kontaminirane gnojivima tijekom kultivacije. Utvrđeno je da je raspon koncentracija radionuklida u analiziranim uzorcima unutar vrijednosti koje preporuča UNSCEAR.
A different, reliable, and cost-effective strategy for the analysis of aflatoxins, ochratoxin A, and zearalenone in corn-based foods was proposed, including one multi-toxin immunoaffinity column ...(IAC) sample preparation and three different high-performance liquid chromatography fluorescence detection methods. The analytical procedures were tested and verified, keeping in mind their occurrence at trace levels in corn-based foods. With the validation of the proposed multi-toxin IAC methodology and comparison of the performance characteristics with methods using a single-toxin IAC, we confirmed the reliability of the multi-toxin IAC procedure versus the single-toxin IAC. The methods were validated by revealing satisfactory performance characteristics; for example, the obtained values of limit of detection were significantly lower than the maximum limits for all mycotoxins of concern. In addition, the recovery values were between 70.9 % and 106.1 % for all mycotoxins of interest, with precision values lower than 10.5 %.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The aim of this study was to construct two plasmid-specific shRNA transcripts of the bcl-2 gene in order to prepare for reverse of cell apoptosis. The plasmid was designed according to a previously ...published sequence of interfering RNA following an appropriate reference, using appropriate software. By annulling complementary oligonucleotides, double-stranded inserts were formed. Recombinant shRNA-encoding plasmids were constructed by digestion of psiRNA-x7SKGFPzeo plasmid (psiRNA-x7SKGFPzeo, with restrictive endonuclease BbsI electrophoresis in ultra-pure agarose with low melting point (LMP-Agarose). For each of the constructs, a suitable double-stranded insert downstream of x7SK (strong RNA III promoter) with T4 DNA ligase was cloned. The control plasmid psiRNAScr was used directly for transformation. The PC-3 cell lines were transfected with 2 plasmids, psiRNA-Bcl-2 and psiRNAScr to suppress the bcl-2 gene construct. The results have shown that the lowest level of bcl-2 genes was 48 h, and even lower 72 h after the transfer, and the mRNA levels returned to normal in 120 h. An increase in the percentage of cells with spontaneous apoptosis has been observed with successful inhibition of the bcl-2 gene. The induction of apoptosis in transfected cells increased the percentage of necrotic cells proportionally. The percentage of apoptotic cells transfected with psiRNA-bcl-2 plasmid increased proportionally to the increase of hydrogen peroxide concentration. The transfection of the PC-3 cell line from prostate cancer with constructed shRNA plasmid has induced suppression of bcl-2 gene expression versus control Scr plasmid. Suppression of bcl-2 gene expression significantly increased cell sensitivity to apoptosis induction.
Detecting meat fraud in food supply chain Crceva-Nikolovska, Radmila; Angeleska, Aleksandra; Nikolovski, Aleksandar ...
Western Balkan Journal of Agricultural Economics and Rural Development,
2019, Volume:
1, Issue:
2
Journal Article
Open access
In recent years, numerous reports have repeatedly highlighted a series of food safety scandals involving contaminated and forged meat and fish products, grains and fruit products, juices, cooking ...oils, and spices and herbs, distilled beverages and pet treats. Foods that have been found to be stained with chemicals, illicit drug residues, additives and dyes, pathogenic microorganisms and other pests. Some foods enter the market have expired well or are unhygienic. Economic gain is the goal of food fraud. Food fraud and the prevention of such fraud are very important processes in the food industry. Such frauds are economically motivated, rated as criminal behaviour, and the moment we understand criminal behaviour and decision making we will be able to calculate and exclude the risk of food fraud. By analysing financially motivated fraud that combine opportunities, motivations, and inadequate control measures, we can assess the likelihood of fraud in any food product or component. The modified ingredients are specially designed to avoid quality assurance and quality control systems for customers. Only people who manipulate the ingredients know what substances and how to manipulate them. In addition, fraudulent ingredients are often unconventional substances that do not meet the requirements of food safety management systems, and become known only after they are incorporated into the supply chain. International standards for food and regulations address the risk of fraud food adulteration. European Union (EU) Directives, Global Food Safety Initiative (GFSI) Codex Alimentarius has continued work on a food fraud, or how, food fraud fits into their benchmarking. The problem of detection and typing of meat in meat products in the world and lack of research on them in the Republic of North Macedonia was the main goal for this paper. Our task was identification of meat type by ELISA method and proof of counterfeiting of meat products. Analyses are made in the laboratories of the Institute of Food at the Faculty of veterinary medicine in Skopje A total of 350 samples of various heat-treated meat products subgroups of meat sausages in pieces were examined for detection, typifying and quantifying the type of meat used for production.
PDF
