Integrated analysis of marine biotoxins and contaminants of emerging concern in bivalve mollusks from Santa Catarina, Brazil.

Santa Catarina is the main producer state of oysters and mussels in Brazil, reaching 98 % of national production. To assure the safety of bivalve mollusks production, control programs of marine biotoxins (MBs) have been continuously performed. Herein, the co-occurrence of MBs and contaminants of emerging concern (CECs) in oyster and mussels from the main production sites of Santa Catarina was reported, covering 178 compounds. Samples of wild and non-cultivated oysters and mussels were also assessed. Chemometric tools were used to evaluate and optimize several sample preparation techniques such as solid-liquid, ultrasound assisted, and pressurized liquid extraction. The optimized protocol was based on ultrasound assisted extraction followed by liquid chromatography coupled to tandem mass spectrometry. The results showed the incidence of several CECs and MBs. In the case of MBs, all results were below the regulatory limits for both cultivated and non-cultivated samples. Wild mollusks have shown a higher number of compounds. Regarding CECs, the more frequent compounds were caffeine, diclofenac, meloxicam, and sertraline. Domoic acid and okadaic acid were the main toxins detected. The results highlighted the need of monitoring for MBs and the potential of oyster and mussels as sentinel organisms to risk analysis of CECs in coastal regions. To the best of our knowledge, this is the first method to describe a simultaneous sample preparation and analysis of CECs and MBs in bivalve mollusks, as well as the first report of meloxicam and florfenicol in mussels and oysters.

Sample pooling and incurred samples improve analytical throughput and quality control of lipophilic phycotoxins screening in bivalve mollusks.

Lipophilic marine biotoxins (LMBs) are one of the main risks associated with the consumption of mussels and oysters. Sanitary and analytical control programs are developed to detect the occurrence of these toxins in seafood before they reach toxic levels. To ensure quick results, methods must be easy and fast to perform. In this work, we demonstrated that incurred samples were a viable alternative to validation and internal quality control studies for the analysis of LMBs in bivalve mollusks. These samples were used to optimize, validate, and monitor a simple and fast ultrasound-assisted extraction (UAE) procedure. An internal quality control material containing okadaic acid (227 ± 46 µg kg-1) was produced and characterized. This material had its homogeneity and stability verified and was included as a quality control in all batches of analytical routine. Besides, a sample pooling protocol for extracts analysis was developed, based on tests for COVID-19. Up to 10 samples could be analyzed simultaneously, reducing the instrumental time of analysis by up to 80%. The UAE and sample pooling approaches were then applied to more than 450 samples, of which at least 100 were positive for the okadaic acid group of toxins.

Simultaneous extraction/derivatization for the analysis of sulfite by capillary electrophoresis: A high-throughput reference method to meet the demand of seafood inspection.

Sulfite is widely used to prevent enzymatic browning in shrimp and lobster processing. However, sulfite may cause allergy in sensitive consumers. Thus, regulatory agencies set limits for its use. Sulfite is usually controlled by the normalized Monier-Williams (MW) titrimetric method that allows a limited number of samples to be analyzed. This manuscript consolidates an innovative method for sulfite inspection in seafood by capillary zone electrophoresis with diode array detector (CZE-DAD). A simple, fast, and simultaneous extraction and derivatization method was developed to provide high throughput for analytical routine. The high instability of the sulfite was suppressed by its derivatization with formaldehyde producing hydroxymethylsulfonate. The evaluation of its analytical performance yielded excellent results in compliance with the strict parameters required for metrological accreditation. The CZE-DAD method was selective and specific when submitted to confirmatory evaluations by liquid chromatography coupled to mass spectrometry. The limit of detection (3.50 mg kg-1), limit of quantitation (11.7 mg kg-1) and recoveries (99-103%) were adequate for sample analysis. The measurement uncertainty was estimated by the propagation of errors and experimental standard uncertainties (precision, accuracy, and analytical curves) and type B uncertainties from traceable measurement instruments. The low relative uncertainty (10%) and the adequate reproducibility demonstrated method suitability. The CZE-DAD results were compared to the MW method through the respective expanded standard uncertainties and normalized error. This new method is promising to be used in seafood inspection and continuous laboratory evaluations using instrumentation not very expensive to acquire and maintain.

Disasters with oil spills in the oceans: Impacts on food safety and analytical control methods.

More than 5.8 million tonnes of oil have been spilled into the oceans. Some oil disasters marked history, causing multiple social and economic consequences in addition to catastrophic environmental impacts. Recently, Brazil and Mauritius faced oil disasters that have severely impacted seafood sanitary credibility. One of the components of the oil composition are the polycyclic aromatic hydrocarbons (PAH), which are the main contamination markers of petrogenic origin. There is enough evidence to correlate the intake of food contaminated with PAH with increased risks of developing cancer. The set PAH4, composed of benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, and chrysene, and the set PAH8, composed of benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[ghi]perylene, chrysene, dibenzo[a,h]anthracene, and indeno[1,2,3-cd]pyrene are recognized as markers of food chemical contamination. After oil disasters in the oceans, the risk to the health of seafood consumers tends to be of special concern, Countries like the European Union set maximum levels for benzo[a]pyrene (5 µg kg-1) and PAH4 (30 µg kg-1) in bivalve mollusks. Levels of concern established by countries that have faced oil disasters are given special attention in this review. Laboratory analysis of PAH in food samples is very challenging because it deals with quite different kinds of matrices. Furthermore, analytical results are usually related to the closure or reopening of cultivated areas and fishing points. Therefore, the progress of the analytical methods for PAH in seafood is covered in detail. Chemical laboratory measurements provide essential data to assess the potential risks to human health due to consumption of seafood contaminated with PAH. The main human health risk assessment approaches in a seafood contamination scenario with PAH are reviewed and discussed, providing an insightful and guiding tool to each step of the risk assessment framework.

Reference LC-MS/MS method to detect fresh cheeses adulteration with whey.

This study evaluated the potential of a reference method to detect fresh cheeses adulteration with whey by liquid chromatography coupled to mass spectrometry (LC-MS/MS). Qualitative results were expressed as presence or absence of the marker peptide TPEVDDEALEK, obtained by tryptic hydrolysis of ß-lactoglobulin. Sample preparation was based on defatting with cold acetone and protein solubilization in ammonium bicarbonate and urea buffer (pH = 8.0). Reversed phase liquid chromatography used a C18 column for separation of the analyte, whose retention time was 4.12 min. Mass spectrometry was carried out with positive electrospray ionization (ESI+) in multiple reaction monitoring (MRM) mode for the precursor ion (m/z 624) and the quantitation (m/z 573) and confirmation transitions (m/z 820; m/z 920) of the peptide. Method validation was carried out in quantitative terms, to set the baseline concentration of the marker peptide in 69 authentic samples, and in qualitative terms, to set the action level that distinguish authentic from adulterated cheeses (350 mg kg-1). Sensitivity was enough to detect cheeses with 10% adulteration and the detection limit was set to 21 mg kg-1. The simple extraction procedure allowed high-throughput analysis of 33 real samples. Results were compared to SDS-PAGE electrophoresis, whose limitations for accurate quantitation were easily overcome by LC-MS/MS. The developed method ensured precision, accuracy, sensitivity, and specificity needed for the unequivocal detection of non-compliant cheeses made with cow or buffalo milk, without dealing with the highly toxic chemical species required for SDS-PAGE. This method can be extended in the future to detect similar adulterations in fresh cheeses prepared with milk from other animal species, as well as in other dairy products.

Cassava-based materials for matrix solid phase dispersion: An alternative for sample preparation in food analysis.

Cassava-based food ingredients were evaluated as candidate materials to be used as matrix solid phase dispersion (MSPD) for sample preparation. Cassava starch, tapioca, and tapioca pearls (TP) were applied in MSPD sample preparation of several food matrices such as mussels, fish, cooked ham, sausages, and animal feed (laying mash) for the determination of pharmaceuticals, preservatives, and polycyclic aromatic hydrocarbons by liquid chromatography coupled to tandem mass spectrometry or capillary electrophoresis. The performance of the new cassava-based solid phases was compared to other materials, such as diatomaceous earth, cellulose, cork powder, and a commercial polymer (Q-matrix® Hydra). The following parameters were used to select the most appropriate solid phases for each assay: fat removal, accuracy for certified reference material analysis, interferents presence in blank samples extract, signal to noise ratio, signal enhancement, and signal suppression. Best results were observed for cassava starch, except for nitrite and nitrate analysis, where the use of cellulose have led to the best sample preparation performance. Electronic microscopy of the materials and the mixture matrix and solid phase confirmed the adequate dispersion of the matrix on cassava starch. In conclusion, cassava-based solid phases were suitable for MSPD, allowing cheaper, greener, and abundant alternatives to sample preparation.

Quantification of pyrrolizidine alkaloids in Senecio brasiliensis, beehive pollen, and honey by LC-MS/MS.

This article presents the determination of eight pyrrolizidine alkaloids (PAs) by LC-MS/MS in honeys, pollen, and Senecio brasiliensis (Asteraceae) samples, all from Santa Catarina state, Brazil. In addition, the Box-Behnken design was used to perform an optimized sample preparation on pollens and S. brasiliensis parts. Senecionine and its N-oxide, besides retrorsine N-oxide, were determined in six of the seven honeys samples. Pollen from species of the Asteraceae, Fabaceae, and Boraginaceae families were found with greater predominance in three of the seven honeys samples. In these three honeys samples were also found the highest PAs levels. In beehive pollen, flower, and leaf of S. brasiliensis, the total levels of PAs and their N-oxides reached 221, 14.1 × 104, and 14.8 × 104 mg kg-1, respectively. In honeys, these compounds are chemical contaminants and therefore undesirable when the sum exceeds 71 µg kg-1, according to EFSA. On the other hand, although PAs are naturally present in plant and pollen of some species (Senecio, Crotalaria, Bacharis, Ecchium, Mimosa scabrella, Vernonia), it is important to monitor their levels in plants but also in honeys, and other beehive products since these compounds are transferred to the final product.

Reducing FODMAPs and improving bread quality using type II sourdough with selected starter cultures.

This study focussed on lactic acid bacteria (LAB) screening for sourdough type II elaboration and evaluating the effects of sourdough fermentation in bread making, focussing mainly on reducing FODMAPs. After a technological performance screening, six strains (Levilactobacillus brevis, Weissella minor, Lactiplantibacillus plantarum, Leuconostoc citreum, Limosilactobacillus fermentum, and Companilactobacillus farciminis) were selected for sourdough preparation. Total titratable acidity, pH, specific volume, and enumeration of microorganisms were carried out on sourdoughs, doughs, and breads. Breads were subjected to texture profile and colour analysis, moulds and yeast enumeration, and total fructans (main group of FODMAPs) quantification. Breads produced with sourdough showed a significant reduction of fructans, greater acidity, volume, and better performance during storage when compared to fermentation using only baker's yeast. Including specific cultures as starters in sourdough reduced fructans content by >92%, thereby producing a low FODMAP bread suitable for Irritable Bowel Syndrome patients with improved nutritional and technological properties.

Residues of antibiotics in yeasts from ethanol production: a possible contamination route for feedingstuffs.

Sugarcane yeast and brewer's yeast from ethanol production are widely used as ingredients of animal feed formulations in Brazil. To avoid the contamination of the must in ethanol production refineries, the use of antibiotics is one of the main preventive treatments. Thus, there is a risk of antibiotic residues carry over from yeast to animal feed. This unintentional addition of antibiotics can produce non-compliant feed products, due to regulatory aspects and their toxicity for animals. The results of an exploratory program to assess the occurrence of over 60 antibiotics and other pharmaceuticals in 27 sugarcane yeast and brewer's yeast samples were described. Monensin was present in seven samples with concentrations ranging from 0.47 to 263.5 mg kg-1. Other antibiotics quantitated were virginiamycin (2.25 mg kg-1) and amprolium (0.25 mg kg-1). Monensin in sugarcane yeast may represent a risk for further feeds production, especially for those products intended for sensible species such as equines and rabbits, for which monensin has toxic effects.

The potential of bacterial cultures to degrade the mutagen 2-methyl-1,4-dinitro-pyrrole in a processed meat model.

Processed meats are classified by the International Agency for Research on Cancer as category 1 because their consumption increase the incidence of colorectal and stomach cancers. Meat processing widely employs nitrite and sorbate as preservatives. When these preservatives are concomitantly used in non-compliant processes, they may react and produce the mutagen 2-methyl-1,4-dinitro-pyrrole (DNMP). This study aimed to evaluate the ability of different bacteria isolated from food matrices to biodegrade DNMP in in vitro reactions and in a processed meat model. A possible mechanism of biodegradation was also tested. In vitro experiments were performed in two steps. In the first one, only one strain out of 13 different species did not interact with DNMP. In the following step, an empirical conversion factor was calculated to assess the conversion of DNMP to 4-amino-2-methyl-1-nitro-pyrrole by the strains. The most efficient strains were Staphylococcus xylosus LYOCARNI SXH-01, Lactobacillus fermentum LB-UFSC 0017, and Lactobacillus casei LB-UFSC 0019, which yielded conversion factors of 0.62, 0.60, and 0.43, respectively. Thus, such strains were individually added to the processed meat model and completely degraded the DNMP. Moreover, S. xylosus degraded DNMP in less than 30 min. The enzymatic mechanism was evaluated using its cell-free extract. It showed that, in the aerobic system, reduction rates were 30.321 and 22.411 nmol/mg of protein/min using NADH and NADPH, respectively. A DNMP reductase was assigned to the extract and a potential presence of an oxygen insensitive nitroreductase type I B was considered. Thus, biotechnological processes may be an efficient strategy to eliminate the DNMP from meat products and to increase food safety.

Determination of 62 veterinary drugs in feedingstuffs by novel pressurized liquid extraction methods and LC-MS/MS.

A fast and simple method for the determination of 62 veterinary drugs in feedingstuffs was developed, optimized, validated, and applied to real samples. Sample preparation was based on a pressurized liquid extraction method using a hard cap coffee machine, which was compared to a commercial pressurized liquid extraction system. Extraction was performed with diatomaceous earth, acetonitrile (20%), and formic acid (0.1%). A central composite design was used to optimize the composition of the extraction solvent. The extracts were analyzed using two chromatographic modes (reversed phase with C18 and HILIC). Analytical limits were set to 25 (limit of detection) and 75 µg kg-1 (limit of quantitation). For banned substances, a salting-out step was included, achieving LOQ lower as 1 µg kg-1 for ractopamine. Other figures of merit such as precision, trueness, decision limit (CCα), method capability (CCß), matrix effects, stability, recovery, and measurement uncertainty were also reported for analytical validation. The method was successfully applied to hundreds of real samples demonstrating its fitness-for-purpose for the analysis of sulfonamides, tetracyclines, fluoroquinolones, avermectins, quinolones, beta-agonists, beta-lactams, amphenicols, benzimidazoles, coccidiostats, lincosamides, macrolides, nitrofurans, quinoxalines, melamine, and trimethoprim.

A new analytical concept based on chemistry and toxicology for herbal extracts analysis: From phenolic composition to bioactivity.

Studies regarding the bioactivity of teas are mainly based on the phenolic composition and in vitro antioxidant activity of the herbal species used in their preparation. The aim of this study was to compare the in vitro and ex vivo antioxidant activity, cytotoxic/antiproliferative activity against cancer cells, the inhibitory activity of α-amylase, α-glucosidase and angiotensin I-converting enzymes, as well as the inhibition of DNA-induced fission of the peroxyl radical, in relation to aqueous extracts of Camellia sinensis var. sinensis (CS), Ilex paraguariensis (IP), Aspalathus linearis (AL) and an optimised extract (OT) containing the three herb species. A bivariate and multivariate statistical approach was employed to associate functional activities with individual phenolic composition. The CS and OT extracts showed the highest levels of hesperidin, quercetin-3-rutinoside, (-)-epigallocatechin-3-gallate and isoquercitrin. The CS and OT extracts showed the highest antioxidant activity, greater ability to inhibit α-amylase and proliferation of HCT8 cells, and greater ability to reduce Folin-Ciocalteu reagent. The AL extract, which is the major source of quercetin-3-rutinoside, hesperidin and isoquercitrin, showed the highest ability to inhibit α-glucosidase, the inhibition of LDL oxidation and protection of human erythrocytes. The IP extract showed the highest inhibition of lipoperoxidation in brain homogenate of Wistar rats, antihypertensive activity, and A549 cell proliferation; chlorogenic acid was its major phenolic compound. In general, the in vitro functionality of each extract was dependent on its chemical composition and the OT extract presented the most varied phenolic composition, and biological activity similar to the CS sample. In conclusion, the mixture of CS, AL, and IP represents a chemical and functional-based strategy to develop functional teas.

Assessing the mutagens ethylnitrolic acid and 2-methyl-1,4-dinitro-pyrrole in meat products: Sample preparation and simultaneous analysis by LC-MS/MS.

The simultaneous use of nitrite and sorbate as preservatives in meat products may produce mutagenic compounds such as the ethylnitrolic acid and 2-methyl-1,4-dinitro-pyrrole. We developed a sensitive analytical method with high metrological reliability. After assessing several extraction approaches and chromatographic separation modes, a modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) approach was chosen for sample preparation, which were analyzed by reversed-phase liquid chromatography (with C18 as stationary phase) coupled to tandem mass spectrometry. After validation, we confirmed that this method is fit-for-purpose, since it was applied to the analysis of several meat products. Limits of detection were set from 5 to 20 µg kg-1. Satisfactory results were obtained for both compounds, such as precision (CV > 20%) and recoveries (77-92%). This method determine these carcinogenic compounds in processed meats, contributing to the preservation of public health and the improvement of food regulation and control.

Microbial biotransformation of N-nitro-, C-nitro-, and C-nitrous-type mutagens by Lactobacillus delbrueckii subsp. bulgaricus in meat products.

Processed meats are classified by the International Agency for Research on Cancer (IARC) as carcinogenic to humans. However, information on the responsible agents and the influence of industrial processing on the increased risk of cancer is still lacking. This study aimed to use cultures of Lactobacillus delbrueckii subsp. bulgaricus LB-UFSC 01 to biodegrade harmful C-nitrous, N-nitro, and C-nitro compounds in processed meat matrix. Firstly, positive results for ethylnitrolic acid (ENA) (>5.00 µg kg-1) and 2-methyl-1,4-dinitro-pyrrole (DNMP) (>12.0 µg kg-1) were obtained in mortadellas produced under different experimental conditions employing preservatives and antioxidants. Mortadellas containing nitrite and sorbate in the ratio of 8:1 (w/w) yielded the highest concentrations of mutagens. However, the treatment with the LB-UFSC 01 culture was able to modulate the harmful compounds in the mortadella samples. Several analytical methods employing liquid chromatography coupled to mass spectrometry and statistical models were employed to identify the metabolites and reaction routes during microbial biotransformation. For the first time, relevant information regarding the formation and degradation of ENA and DNMP in a processed meat model simulating real conditions was presented.

The potential of the pecan nut cake as an ingredient for the food industry.

Pecan nut [Carya illinoinensis (Wangenh.) K. Koch] cake (PNC) is a co-product from the oil extraction industry and its potential as an ingredient for the food industry are not well known. In this work, the nutritional composition and the functional properties of PNC were studied. Additionally, the influence of different solvents (ethanol, water, and acetic acid) on the phytochemical composition and antioxidant capacity (reducing potential of the hydrophilic compounds - RPHC, 2,2-diphenyl-1-picrylhydrazyl - DPPH, and total reducing capacity - TRC) of PNC extracts were established using a simplex-centroid design. PNC is a source of carbohydrates, protein, and dietary fiber (40.5; 21.87 and 13.01 g 100 g-1, respectively). The PNC exhibited a low energy value when compared to the raw nut (398.8 kcal 100 g-1 and 645.54 kcal 100 g-1, respectively). Mg, Mn and Co (416.74; 23.21 mg 100 g-1 and 59.00 µg 100 g-1, respectively) were the main minerals identified in PNC. The PNC also presented functional properties such as emulsifying and oil absorption capacities and a great ability to absorb water. Using the proposed solvent mixture system, the content of total phenolic compounds and condensed tannins recovered from PNC ranged between 172.43 and 2744.24 mg GAE 100 g-1, and 253.42 to 1376.44 mg CE 100 g-1, respectively. The antioxidant capacity of the PNC extract was showed through its ability to reduce hydrophilic (172.06-1714.96 mg GAE 100 g-1) to transfer hydrogen atoms (12.55-74.11% scavenging activity) and lipophilic compounds (509.87-2070.80 mg QE 100 g-1) using RPHC, DPPH, and TRC methods, respectively. Combining ethanol, water, and acetic acid at 30 °C for 15 min, positively affects the extraction of bioactive compounds from PNC, as well as the antioxidant activity of the extracts. The physicochemical, functional, phytochemical, and antioxidant properties demonstrate that pecan nut cake may represent a potential ingredient or additive for the food, pharmaceutical, and cosmetic industries.

Interactions of preservatives in meat processing: Formation of carcinogenic compounds, analytical methods, and inhibitory agents.

Meat products are important for balanced diets because of their nutritional richness. However, noxious compounds may be formed by interactions among reactants and specific conditions in processed meats. N-nitroso compounds, heterocyclic aromatic amines, polycyclic aromatic hydrocarbons, 1,4-dinitro-2-methyl pyrrole (DNMP), and ethyl nitrolic acid (ENA) are among the main compounds of toxicological concern. This review corroborates the International Agency for Research on Cancer (IARC)'s decision to classify those foodstuffs as carcinogenic to humans. Furthermore, this paper also aimed at clarifying how noxious compounds are formed in meat products, as well as their health effects for consumers. The preservatives abuse and the use of forbidden additives may increase the formation of carcinogens. Risks are not only due to preservatives, since some compounds are formed during processing or digestion, without clear link to any additive. Regulation should set specific residue limits for other noxious compounds in meat products, such as DNMP and ENA. The scope of control programs should be extended instead of assessing the proper use of additives only. Thus, reliable analytical methods for the quantitation of carcinogens should be available. Fermentative and enzymatic processes for bioconversion are among the main strategies to solve these problems in foodstuffs. The use of antioxidants is the most common approach, because of its low cost and effectiveness. In the future, the IARC classification should rather consider different categories of processing, as well as the chemical and microbiological composition of meat products. Further studies are still required to clarify the increase on cancer risk due to the consumption of meat products and to elucidate the main mechanisms of carcinogenicity. Notwithstanding, such carcinogens cannot be neglected, but continuously investigated, including their health implications in relation to other foods.

Antioxidants-rich ice cream containing herbal extracts and fructooligossaccharides: manufacture, functional and sensory properties.

This work aimed to optimize an aqueous extract rich in phenolic compounds and potential functional properties made of Ilex paraguariensis, Melissa officinalis, and Cymbopogon citratus. The lyophilized extract was used for the development of an ice cream. Total phenolics, FRAP, DPPH, Folin-Ciocalteu's reducing capacity, and total reducing capacity of different combinations of herbal extracts were tested and modeled using response surface methodology. Simultaneous optimisation was employed to maximize the bioactive compounds in the extract and the lyophilized optimum combination was added to ice cream. The lyophilized extract contained quercetin-3-rutinoside, hesperidin, isoquercetin, caffeic acid, and 5,7-dihydroxyflavone. The optimised extract, which showed antihypertensive, antidiabetic, and antioxidant activity using in vitro protocols, increased total phenolics and antioxidant activity in comparison to the control ice cream. The ice cream presented a sensory acceptance index of 83%. After 72 days of storage (-18 °C), total phenolics and antioxidant activity significantly decreased.

Carry-over and contamination of veterinary drugs in feed production lines for poultry and pigs.

The current model of pigs and poultry production has increased stocking density and reduced downtime between lots. This scenario may favour a rise of infection and disease risk in animals. To avoid this problem, routine use of drugs has been made, intensifying the possibility of residues in animal products and antimicrobial resistance. The aim of this study was to measure carry-over and contaminants of veterinary drugs included in the feed production lines for poultry and pigs. Samples were taken from 25 production lines. LC-MS/MS was used for simultaneous analysis of 62 active ingredients. In the medicated feed, 80.4% of the samples had a concentration of active ingredients different from the stated doses. In 70% of the feed samples, there was heterogeneity in the mixture of active ingredients. In subsequent feeds, carry-over was greater than 1% of the stated dose in 63% of cases. Of the 25 analysed lines, only one showed no contamination with other active ingredients. No correlations were found between the nutritional composition of the feed and carry-over. The present study demonstrated that the current production model allows the occurrence of unwanted drugs in feed-in doses that can contaminate animal products and can select antimicrobial-resistant bacteria.

Determination of ractopamine residue in tissues and urine from pig fed meat and bone meal.

In many countries, ractopamine hydrochloride (RAC) is allowed to be used in animal production as a ß-agonist, which is an energy repartitioning agent able to offer economic benefits such as increased muscle and decreased fat deposition, feed conversion improvement and an increase in average daily weight gain. However, some countries have banned its use and established strict traceability programmes because of pharmacological implications of ß-agonist residues in meat products. In Brazil, commercial RAC is controlled (5-20 mg kg-1) and only added to pig diet during the last 28 days before slaughter. However, the control is more difficult when co-products, like meat and bone meal (MBM), which can be produced from RAC treated animals, are part of the feed composition. Therefore, a study was undertaken to evaluate the presence of RAC residue concentrations in urine and tissues of gilts (n = 40) in four dietary groups: 0%, 7%, 14% and 21% (w/w) of MBM-containing RAC (53.5 µg kg-1). The concentration of RAC residues in MBM, pig tissues and urine was determined by LC-MS. Low RAC concentrations were detected in muscle, kidney, liver and lungs (limit of detection = 0.15, 0.5, 0.5 and 1.0 µg kg-1, respectively); however, no RAC residues were quantified above the limit of quantification (0.5, 2.5, 2.5 and 2.5 µg kg-1, respectively). In urine, the RAC concentration remained below 1.35 µg L-1. These data suggest that MBM (containing 53.5 µg kg-1 RAC) added to diet up to 21% (w/w) could hamper the trade where RAC is restricted or has zero-tolerance policy.