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By increasing the resistance of seeds against abiotic and biotic stress, the possibility of cereal mold contamination and hence the occurrence of secondary mold metabolites mycotoxins decreases. The use of biological methods of seed treatment represents a complementary strategy, which can be implemented as an environmental-friendlier approach to increase the agricultural sustainability. Whereas the use of resistant cultivars helps to reduce mold growth and mycotoxin contamination at the very beginning of the production chain, biological detoxification of cereals provides additional weapons against fungal pathogens in the later stage. Most efficient techniques can be selected and combined on an industrial scale to reduce losses and boost crop yields and agriculture sustainability, increasing at the same time food and feed safety. This paper strives to emphasize the possibility of implementation of biocontrol methods in the production of resistant seeds and the prevention and reduction in cereal mycotoxin contamination.

Documented cases of mycotoxin occurrence in meat products call for further research into potential contamination sources, especially given an ever more increasing consumption of these nutritionally rich products. These foodstuffs can be contaminated with mycotoxins through three pathways: contaminated spices and other raw materials, mycotoxin-producing moulds present on the surface of dry-cured meat products, and carry-over effect from farm animals exposed to contaminated feed. In order to establish meat products’ mycotoxin contamination more precisely, the concentrations of all mycotoxins of relevance for these products should be determined. This manuscript reviews data on major mycotoxins present in different types of meat products, and discusses the contamination pathways, contamination levels and control & preventative measures.

Contamination of milk with aflatoxin M1 (AFM1) is related to the feed for milking cows, which is contaminated with aflatoxin B1 (AFB1). Feed AFB1 converts to AFM1 by dehydrogenation. In this study, we used Lactic acid bacteria (LAB) isolated from raw milk and its products and commercial or laboratory-made beta-glucan isolated from yeast and oats to establish how these mycotoxin binders affect the quality of sterilised, long-life, 2.8% fat milk contaminated with 0.05 mg/L of AFM1. We took the content of fats, carbohydrates, sugars (lactose), and proteins, and the calculated energy values for quality parameters. The mean energy value of the milk treated with AFM1 binders ranged between 85.7% and 101.5% of the control, untreated milk, whereas the fat content ranged between 65.3% and 100.7%. The protein content ranged between 64.4% and 101.1%, carbohydrates between 83.1% and 103%, and lactose between 76.3% and 100.8%. The results indicated a good possibility of binding of AFM1 with Lactobacilus plantarum bacteria, and 0.01% of β-glucan from oats was 0.005% of β-glucan isolated from yeast from Saccharomyces cerevisiae 20. These findings suggest that milk treated with these binders can be processed further and that its treatment significantly reduces the risk of exposure through diet and the related economic damage.

Limbal Stem Cell Deficiency (LSCD) is a very serious and painful disease that often results in impaired vision. Cultivation of limbal stem cells for clinical application is usually performed on carriers such as amniotic membrane or surgical fibrin gel. Transplantation of these grafts is associated with the risk of local postoperative infection that can destroy the graft and devoid therapeutic benefit. For this reason, electrospun scaffolds are good alternatives, as proven to mimic the natural cells surroundings, while their fabrication technique is versatile with regard to polymer functionalization and scaffolds architecture. This study considers the development of poly(&epsilon, caprolactone) (PCL) immune-compatible and biodegradable electrospun scaffolds, comprising cefuroxime (CF) or titanium dioxide (TiO2) active components, that provide both bactericidal activity against eye infections and support of limbal stem cells growth in vitro. The PCL/CF scaffolds were prepared by blend electrospinning, while functionalization with the TiO2 particles was performed by ultrasonic post-processing treatment. The fabricated scaffolds were evaluated in regard to their physical structure, wetting ability, static and dynamic mechanical behaviour, antimicrobial efficiency and drug release, through scanning electron microscopy, water contact angle measurement, tensile testing and dynamic mechanical analysis, antimicrobial tests and UV-Vis spectroscopy, respectively. Human limbal stem cells, isolated from surgical remains of human cadaveric cornea, were cultured on the PCL/CF and PCL/TiO2 scaffolds and further identified through immunocytochemistry in terms of cell type thus were stained against p63 marker for limbal stem cells, a nuclear transcription factor and cytokeratin 3 (CK3), a corneal epithelial differentiation marker. The electrospun PCL/CF and PCL/TiO2 successfully supported the adhesion, proliferation and differentiation of the cultivated limbal cells and provided the antimicrobial effect against Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans.

The aim of this study was to estimate a level of citric and tartaric acids in fruit nectars (n = 17) and juices (n = 13) available on the Croatian market. For analysis reverse-phase HPLC with UV/Vis detector set at 214 nm was used. Mobile phase was phosphate buffer (50 mM, pH = 2.80) at flow rate 0.5 mL min–1. The method was linear (r2 = 0.9999). LoD was 0.01 g L–1, LoQ was 0.03 g L–1 and the intra-day along with the inter-day variability were up to 3 %. The level of citric and tartaric acids in fruit nectars ranged from 1.26 to 4.42 g L–1 and 0.68 to 0.86 g L–1, respectively, and in fruit juices ranged from 3.03 to 7.67 g L–1 and 3.09 to 4.68 g L–1, respectively. A higher level of citric acid in fruit juices than in fruit nectars was detected (p < 0.05; MannWhitney U test). Six fruit juices contained a higher level of citric acid allowed by EU regulation implying the importance of monitoring concentrations of both acids in food products. This work is licensed under a Creative Commons Attribution 4.0 International License.

Toxicity of gamma irradiated mycotoxins aflatoxin B1 (AFB1) and ochratoxin A (OTA) was investigated in vitro. AFB1 and OTA stock solutions (50 mM, in methanol) were gamma irradiated (5 and 10 kGy) and non-irradiated and irradiated mycotoxins solutions were tested for cytotoxicity on Pk15, HepG2 and SH-SY5Y cell lines (MTT assay, 1–500 lM concentration range ; 24 h exposure). Degradation of mycotoxin molecules was examined by liquid chromatography tandem mass spectrometry (HPLC-MS/MS). AFB1 and OTA radiolytic products were less toxic than the parent mycotoxins to all of the tested cell lines. Gamma irradiation even at 5 kGy had effect on AFB1 and OTA molecules however, this effect was dependent on chemical structure of mycotoxin. Since gamma irradiation at low dose reduced initial level of both mycotoxins, and gamma irradiated mycotoxins had lower toxicity in comparison to non-irradiated mycotoxins, it can be concluded that gamma irradiation could be used as decontamination method.

Yeasts have an important role in the biotechnological production of ethanol, as well as in the production of fermented food and beverages. Mycotoxins, secondary metabolites of molds, can contaminate a large number of foods due to their ubiquity and therefore present great risk to human health. Other than their toxicological effects on humans, mycotoxins can have negative effects on various properties of yeasts and consequently limit their use in industry. Therefore, the aim of this work was to determine the effects of aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEA) on metabolic activity and biomass growth of selected yeasts S. cerevisiae, S. uvarum, C. utilis and K. marxianus. The presence of fermentation products was determined with high-performance liquid chromatography after 24h of incubation. In the early stage, all mycotoxin-exposed yeasts had lower metabolic activity as well as biomass growth when compared to control. However, concentrations of metabolic products and biomass reached the control levels by the end of the process, with the exception of C. utilis exposed to zearalenone (ZEA). Adaptive response to exposed mycotoxins suggests that certain yeasts could be used to control mycotoxin concentrations in the production of fermented food and beverages.

Mycotoxins are secondary metabolites toxic for humans and animals produced by some fungal species during their growth and, generally, released into the growing media. Mycotoxigenic fungi can colonize a wide spectrum of food and feedstuff and commodities like cereal seeds, fruits, meat and meat products. The toxic effects depend on a type of mycotoxin and vary from proven carcinogenic effects to cytotoxicity. Due to their high toxicity, only a dozen of mycotoxins are highly considered by legislators and scientist all over the world and their presence in food and feed is limited by legislations of almost all countries. In traditional agriculture chemicals, such as antifungals and antioxidants, are widely used to control mycotoxin contamination of food and feed. This strategy could present severe environmental problems as well as a selection of resistant strains. The research of strategies and methods in mycotoxin control with lower environmental impact has been ongoing for many years. Some more environmental friendly methods to control the presence of mycotoxins in food and feed, like the use of antagonistic strains or the use of plant and mushroom extracts, are reviewed in this work.

As in the traditional production of cheese in lambskin sacks raw cow’s or sheep’s milk is mostly used, the purpose of this study is to see how the production affects the microbiological quality of the cheese. To do that, we tested 39 samples of raw cow’s and sheep’s milk, curd, ripened cheese (15, 30 and 45 days) and lambskin sacks for native microbial population. Two-thirds of the milk, curd and cheese samples had higher counts of staphylococci and enterobacteria than permitted by regulations. Not a single sample had Salmonella and Listeria monocytogenes, but we did find Escherichia coli in sheep’s milk and cheese, and yeast and mould in both types of milk and cheese. Staphylococcus xylosus prevailed in lambskin sacks. Despite the high incidence of S. aureus, even in the final product, staphylococcal enterotoxin was detected in only two sheep’s cheese samples. Among the lactic acid bacteria, Lactococcus lactis and Lactobacillus paracasei prevailed in cow’s cheese, whereas Leuconostoc mesenteroides and Lactobacillus plantarum prevailed in sheep’s cheese. In the lambskin sacks Leuconostoc mesenteroides and Lactobacillus plantarum were predominant. Our findings give an important insight into the fermentation and microbial ecology of the cheese in lambskin sacks.

The aim of this study was to investigate ochratoxin A (OTA) and citrinin (CIT) co- occurrence in different unprocessed cereals (n=189) originating from Croatia during a three- year investigation period (2014-2016) using validated enzyme immunoassay (ELISA) methods. CIT and OTA were determined in 49% and 7% of samples, respectively. Significantly higher (p < 0.05) overall mean concentrations were determined for CIT (66.8 ± 76.0 µg/kg) in comparison to OTA (5.2 ± 1.1 µg/kg). Based on the analysis of all investigated cereals, CIT was found about 15 times more frequently than OTA and in similarly (15-fold) higher concentrations, irrespective of the cultivation year. The results revealed a moderately positive correlation between OTA and CIT concentrations in maize (rs = 0.44) and wheat (rs = 0.59), whereas in barley and oat this correlation (p > 0.01) was not significant.

Natural deep eutectic solvents (NADES) are a new generation of green solvents. They are mixtures of two or three compounds such as choline chloride as a cationic salt and alcohols, acids, amides, amines or sugars as hydrogen-bond donors. Although the majority of NADES’ components are of natural origin and therefore NADES are often presumed to be non- toxic, the evaluation of their toxicity and biodegradability must accompany the research on their synthesis and application. Therefore, the aim of this work was to investigate the effect of ten synthesised NADES towards bacteria (i.e., Escherichia coli, Proteus mirabilis, Salmonella typhimurium, Pseudomonas aeruginosa, Staphylococcus aureus), yeast (i.e., Candida albicans) and human cell lines (i.e., HeLa, MCF-7 and HEK293T). In addition, oxygen radical absorbance capacity (ORAC) method was used to determine the antioxidative activity of the tested NADES. Differences in toxicity response between microorganisms and cell lines were observed, and only NADES that contained organic acid showed toxicity towards the test systems. Furthermore, the NADES containing compounds that possess antioxidative activity also showed antioxidative activity. However, research whose primary purpose is the synthesis and application of NADES must be followed by an evaluation of their biological properties (e.g., antimicrobial activity, toxicity towards animal cells and antioxidative or other biological activity) to find the solvent with the best profile for wider industrial applications.

In order to minimise human exposure to aflatoxin M1 (AFM1) the levels of this highly carcinogenic mycotoxin in milk, heat-treated milk, and other dairy products have been limited to, Kako bi se smanjila izloženost ljudi aflatoksinu M1 (AFM1), razina toga visokokancerogenoga mikotoksina u mlijeku, termički obrađenome mlijeku i drugim mliječnim prerađevinama ograničena je na

In this study, the occurrence of Fusarium mycotoxins deoxynivalenol (DON), zearalenone (ZEA) and fumonisins (FUM) was investigated in a total of 257 samples of unprocessed cereals (maize, wheat and barley), sampled annually in Bosnia and Herzegovina throughout the 2013-2015 harvesting period. The levels of mycotoxins were determined using a validated ELISA method. The results showed maize to be the most contaminated cereal among the three, with DON detected in 85%, ZEA in 73% and FUM in 67% of samples, the mean concentrations of the toxins observed during the study period thereby being 984±957 μg/kg, 326±314 μg/kg, and 1, 259±1, 161 μg/kg, respectively. Twenty samples (7.8%) were proven inadmissible for consumption as foodstuffs (Commission Regulation 1881/2006), and 3 samples (1.2%) were proven inadmissible even as feedstuffs (Commission Recommendation 2006/576/EC). Significantly higher (p < 0.05) mycotoxin levels determined in samples harvested in 2014 as compared to those harvested in 2013 and 2015 could be associated with heavy rainfall periods witnessed in 2014 that could favour the formation of moulds, and consequently also the increased production of Fusarium mycotoxins.

In this study, the levels of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FUM) in unprocessed cereals (n = 189) and cereal-based products (n = 61) were determined using validated ELISA methods. All samples originated from either conventional or organic production corresponded to the 2015 harvest in Croatia. Based on the mean mycotoxin concentrations, the risk for the consumer to exceed the tolerable daily intake (TDI) for these toxins by the consumption of both types of cereals and cereal-based products was assessed. Mycotoxin contamination of organic cereals and organic cereal-based products was not significantly different (p > 0.05). Given that the exposure assessment resulted in a small fraction of the TDI (maximum: DON, 12% of TDI), the levels of the investigated mycotoxins in both types of cereals and cereal-based products from the 2015 harvest did not pose a human health hazard.

Fourier Transform Infrared Spectroscopy (FT-IR) is an analytical technique, which provides unique spectrum for each bacterial species due to the stretching and bending vibrations of functional groups present in cell proteins, nucleic acids, lipids, sugars, and lipopolysaccharides. The potential of Gluconobacter oxydans to bind ochratoxin A (OTA) on surface and changes occurring on the cell surface due to mycotoxin exposure were investigated using the FT-IR. OTA was determined using liquid chromatography tandem mass spectrometry (LC-MS/MS) and the results suggest that G. oxydans is able to bind or degrade OTA by 81%. The results revealed capacity of OTA exposed cells to bind a high amount of the toxins is mirrored in the alteration of the original IR patterns, the latter alteration arising due the presence of numerous functional groups within the toxin structure. Major changes seen in the 1, 800-1, 600 cm-1, 1, 600-1, 450 cm-1 and 1, 300-1, 000 cm-1 regions, mainly correspond to carbonyl, aromatic and ether groups, respectively. These groups are abundant in OTA and increase the existing, or provide new spectrum bands. Additionally, very strong signals in the organic halogen compounds region at 870 cm–1, probably corresponds to the C-C1 vibration taking place in OTA.

Development of green technologies is highly devoted to designing new solvents with good ecotoxicological profle, low cost and desirable technological properties. Natural deep eutectic solvents (NADES) are a new generation of novel alternative solvents. They are mixtures of two or three compounds such as choline chloride, as the cationic salt, and alcohols, acids, amides, amines or sugars as hydrogen-bond donors. NADESs are often presumed to be non-toxic due to natural origin of their constituents, but the evaluation of their toxicity and biodegradability must accompany the research on their synthesis and application. The most of the work reported in the current literature was done on the bacteria and some fungi, while there are only a few scientifc papers publishing results on cytotoxicity of NADESs toward cell lines. Differences in toxicity response between bacteria and cell lines were observed. Most likely, the mechanism of NADES action is associated with its interactions with the cell membranes and therefore could be species- dependent. In the work presented in here we investigated the effect of ten synthesised NADES toward bacteria (Escherichia coli, Proteus mirabilis, Salmonella sp., Pseudomonas aeruginosa, Staphylococcus aureus), yeast Candida albicans and human cell lines (HEK293T, HeLa and MCF-7). Amongst all bacteria evaluated by flter paper diffusion assay, the highest inhibition zone was measured toward Proteus mirabilis, while inhibitory effect was not observed on Candida albicans. Between tested NADESs, high inhibition towards all tested bacteria and yeast was observed with choline chloride:oxalic acid (Ch:OX) and was followed by NADES who also have acidic group as hydrogen-bond donors (malic acid and citric acid). Cytotoxicity toward HEK293T, HeLa and MCF-7 cells was determined by MST assay in the range of concentrations (500 mg ml-1 to 2000 mg ml-1). The highest inhibitory effect on cell growth was observed with Ch:OX which possess moderate cytotoxicity. Other NADES did not caused 50% of growth inhibition in the range of tested concentration so the IC50 value was declared to be > 2000 mg ml-1 i.e. > 5 mM meaning that they possess low cytotoxicity. Overall, our results indicate that is not a good approach to a priori consider NADESs as harmless solvents, simply because most of their forming compounds are benign for humans and the environment. Due to the enormous chemical diversity and huge number of possible combinations, careful and critical assessment of the environmental impact, at least of those NADESs that are likely to have technological application, is needed.

As in the traditional production of cheese in lambskin sacks raw cow’s or sheep’s milk is mostly used, the purpose of this study is to see how the production affects the microbiological quality of the cheese. To do that, we tested 39 samples of raw cow’s and sheep’s milk, curd, ripened cheese (15, 30 and 45 days) and lambskin sacks for native microbial population. Two-thirds of the milk, curd and cheese samples had higher counts of staphylococci and enterobacteria than permitted by regulations. Not a single sample had Salmonella and Listeria monocytogenes, but we did find Escherichia coli in sheep’s milk and cheese, and yeast and mould in both types of milk and cheese. Staphylococcus xylosus prevailed in lambskin sacks. Despite the high incidence of S. aureus, even in the final product, staphylococcal enterotoxin was detected in only two sheep’s cheese samples. Among the lactic acid bacteria, Lactococcus lactis and Lactobacillus paracasei prevailed in cow’s cheese, whereas Leuconostoc mesenteroides and Lactobacillus plantarum prevailed in sheep’s cheese. In the lambskin sacks Leuconostoc mesenteroides and Lactobacillus plantarum were predominant. Our findings give an important insight into the fermentation and microbial ecology of the cheese in lambskin sacks., U tradicionalnoj proizvodnji sira iz mišine uglavnom se koristi sirovo kravlje ili ovčje mlijeko, pa je svrha ovog istraživanja bila odrediti mikrobiološku ispravnost sira u ovisnosti o načinu proizvodnje. Ispitana je autohtona mikrobna populacija u 39 uzoraka, i to sirovog kravljeg i ovčjeg mlijeka, skute, zrelog sira (nakon 15, 30 i 45 dana) i mišine. U dvije trećine uzoraka mlijeka, skute i sira pronađen je veći broj stafilokoka i enterobakterija od dopuštenih vrijednosti. Vrste Salmonella i Listeria monocytogenes nisu pronađene niti u jednom analiziranom uzorku, dok je bakterija Escherichia coli pronađena u ovčjem mlijeku i siru, a kvasci i plijesni u obje vrste mlijeka i sira. U mišini je prevladavala bakterija Staphylococcus xylosus. Iako je bakterija S. aureus bila uvelike zastupljena čak i u konačnom proizvodu, stafilokokni je enterotoksin pronađen u samo dva uzorka ovčjeg sira. U siru iz mišine pripravljenom od kravljeg mlijeka prevladavale su bakterije mliječne kiseline Lactococcus lactis i Lactobacillus paracasei, u onom od ovčjeg mlijeka Leuconostoc mesenteroides i Lactobacillus plantarum, a u samoj mišini Leuconostoc mesenteroides i Lactobacillus plantarum. Dobiveni rezultati daju važan uvid u fermentaciju i mikrobnu ekologiju sira iz mišine.

In this study, the basic chemical and fatty acid compositions of autochthonous Croatian cow and sheep cheeses in a lamb skin sack (local name: ‘‘sir iz mišine’’) were determined. Also, the influences of ripening period and different starter cultures on chemical and fatty acid composition of these cheeses were investigated. Samples of cow (n = 20) and sheep (n = 20) milk cheeses were produced in three different ways: from raw milk without the addition of a starter culture, from pasteurized milk with commercial starter cultures and with previously isolated autochthonous starter cultures (Lactococcus lactis S1 or Lactobacillus plantarum B or a mixture of both). Samples were taken during a 45-day ripening period (on days 0, 15, 30 and 45). The ripening time significantly affected all basic chemical parameters, while different starter cultures significantly (p < 0.05) influenced protein, fat and ash content. Ripening time had no significant effect on the representation of the investigated fatty acid groups (p > 0.05), but a significant difference was found depending on the starter cultures used and the type of cheese analysed, in terms of statistically higher proportion (p < 0.05) of polyunsaturated fatty acids in the finished sheep’s milk cheese (2.58–2.97%) in comparison to the cow’s milk cheese (1.93–2.14%). Fatty acids most represented in the analysed cheeses were palmitic, oleic and stearic acid.

The study focuses on developing novel cott age cheese containing spices with acceptable sensory properties, increased biological value and extended shelf life. Thirty types of cheese with added fresh or dried parsley, dill, pepper, garlic and rosemary were produced. Characterisation of phenolic compounds, antioxidant capacity and antibacterial activity of spices and cheese samples were evaluated. The cheese containing fresh pepper and fresh and dried herbs showed excellent sensory properties, with the best results obtained with fresh sweet red pepper. Dry rosemary had the highest antioxidant and antibacterial activity due to high mass fractions of caffeic and rosmarinic acids as well as high mass fractions of flavones and phenolic diterpenes. The plant extracts examined in vitro and in situ effectively reduce numbers of foodborne pathogens like Salmonella typhimurium, Escherichia coli, Staphylococcus aureus and Listeria monocytogenes, and therefore have potential as natural preservatives and antioxidants., Ovo je istraživanje bilo usmjereno na razvoj novog proizvoda, i to svježeg sira sa začinima, prihvatljivih senzorskih svojstava, povećane biološke vrijednosti i produljene trajnosti. Proizvedeno je trideset vrsta sireva s dodatkom svježeg i sušenog peršina, kopra, paprike, češnjaka i ružmarina. Procijenjeni su sljedeći parametri: svojstva fenolnih spojeva, antioksidacijski kapacitet i antibakterijsko djelovanje samih začina te sireva s dodanim začinima. Sirevi sa svježom paprikom, te svježim i suhim začinima imali su izvrsna senzorska svojstva, a najbolji su rezultati dobiveni dodatkom svježe slatke crvene paprike. Suhi ružmarin imao je najveći antioksidacijski i antibakterijski učinak zbog velikih udjela kavene i ružmarinske kiseline, kao i flavona te fenolnih diterpena. Ispitivanjem in vitro i in situ utvrđeno je da biljni ekstrakti učinkovito smanjuju broj patogenih bakterija, poput Salmonella typhimurium, Escherichia coli, Staphylococcus aureus i Listeria monocytogenes, te da mogu poslužiti kao prirodni konzervansi i antioksidansi.

The aim of this study was to investigate the efficiency of gamma (γ) irradiation in the reduction of ochratoxin A (OTA) present in dry- cured meat products prepared from intentionally contaminated raw materials from OTA-treated pigs. OTA concentrations determined in the samples (n=24) ranged from 25.85 μg/kg in bacon to 17.81 μg/kg in smoked ham. After γ-irradiation at doses of 3, 7 and 10 kGy (i.e. the doses used in the food industry), a dose-depended OTA reduction was observed, however not statistically significant. The mean OTA reduction achieved with 3-kGy, 7-kGy and 10-kGy γ-doses approximated to 8.51%, 13.89% and 22.48%, respectively. The storage of irradiated samples (one month, +4°C) did not significantly affect OTA levels. Based on the correlation between the OTA reduction level and basic chemical composition of dry-cured meat samples, OTA reduction may be linked to the samples’ fat content. The obtained results indicate that γ- irradiation can reduce OTA levels in dry-cured meat products, but only to a limited extent due to the complexity of their matrix.

Detailed investigation on the effect of gamma (γ) irradiation on germination, sporulation, and growth of aflatoxigenic moulds ( Aspergillus parasiticus 2999, Aspergillus flavus 305, and Aspergillus niger 388), as well as on the reduction of aflatoxin B 1 (AFB 1 ) level in artificially and naturally contaminated maize/feed samples was performed. The results of in vitro and in situ experiments with aflatoxigenic moulds demonstrated that 5 kGy-γ irradiation manages to prevent sporulation, germination and growth of the tested moulds both when in form of a pure and when in form of a mixed culture. In the feed samples artificially contaminated with AFB 1 (50 μg kg −1 ) 5 kGy-γ irradiation reduced AFB 1 level by around 60%, while 10 kGy-dose reduce it for around 85%. Similarly, in feed samples spiked with AFB 1 in the concentrations of 100 μg kg −1 5 kGy-dose reduced the AFB 1 level by approximately 70%, while the dose of 10 kGy reduced it by approximately 90%. The experiments on naturally contaminated maize samples (n = 30) confirmed these observations; following a 5 kGy-irradiation, the overall mean AFB 1 reduction equalled to 69.8%, while the irradiation with a 10 kGy-dose achieved the overall mean toxin reduction of 94.5%. The obtained results indicate that γ irradiation can be used to prevent the growth of aflatoxigenic moulds and to reduce the AFB 1 levels in various goods intended for animal and human consumption, thus minimizing the animal and human exposure to this carcinogenic mycotoxin.

Svrha je ovoga istraživanja bila identificirati i okarakterizirati potencijalne autohtone funkcionalne starter kulture izolirane iz domaće kobasice proizvedene od konjskog mesa. Dominantnu su mikrofloru u uzorcima kobasica činile bakterije mliječne kiseline (BMK), a zatim mikrokoki. Od bakterija mliječne kiseline prevladavale su vrste Lactococcus lactis ssp. lactis i Lactobacillus plantarum. Vrsta Lactococcus lactis ssp. lactis nije uobičajena u fermentiranim kobasicama, pa smo ju okarakterizirali kao potencijalnu funkcionalnu starter kulturu. Vrsta Lactococcus lactis ssp. lactis proizvela je značajnu količinu mliječne kiseline, a uspješno je rasla pri 12, 18 i 22 ºC, te u prisutnosti 5 % NaCl. Također je dobro podnijela liofilizaciju i simulirane uvjete želučanog soka i soka tankog crijeva. Osim toga, uspješno je suzbila rast patogena i pokazala je dobra adhezijska svojstva in vitro., The aim of this study is to identify and characterise potential autochthonous functional starter cultures in homemade horsemeat sausage. The dominant microflora in the samples of horsemeat sausage were lactic acid bacteria (LAB), followed by micrococci. Among the LAB, Lactococcus lactis ssp. lactis and Lactobacillus plantarum were the dominant species, and since the first is not common in fermented sausages, we characterised it as a potential functional starter culture. Lactococcus lactis ssp. lactis produced a significant amount of lactic acid, displayed good growth capability at 12, 18 and 22 °C, growth in the presence of 5 % NaCl, good viability after lyophilisation and in simulated gastric and small intestinal juice, antimicrobial activity against test pathogens, and good adhesive properties in vitro.

Fusarium mycotoxins are frequent contaminants of cereals in this part of Europe. In this study, a total of 181 samples of maize, wheat, barley and oat were collected from different fields situated in six Croatian regions, and analysed using a validated ELISA method. Concentrations of deoxynivalenol (DON), zearalenone (ZEA), fumonisin (FUM) and T-2 toxin (T-2) were determined. Methodology validation showed the mean recovery rates to range from 72.8% to 103.6%, with the intermediate precision of 70.699.4% and variation coefficients (CV) of 3.6–6.2% and 6.1–10.2%, respectively. Maize proved itself as the most contaminated cereal, with DON as the most represented Fusarium mycotoxin (52.5%) followed by ZEA (40.5%), FUM (37.5%) and T-2 toxin (33%). Mycotoxin concentrations higher than allowed were observed in 4 maize samples and a single wheat sample. Given the warm and dry study period, such a contamination might be associated with some factors other than climate conditions that could cause Fusarium mycotoxin formation. The obtained data pointed towards the necessity for a consistent control over these contaminants and the definition of their maximal allowed levels in different foodstuffs and feedstuffs.

Fungicides are the most common agents used in postharvest treatment of fruit and are the most effective against blue mould, primarily caused by Penicillium expansum. Alternatively, blue mould can be treated with antagonistic microorganisms naturally occurring on fruit, such as the bacterium Gluconobacter oxydans. The aim of this study was to establish the antifungal potential of the G. oxydans 1J strain isolated from apple surface against Penicillium expansum in culture and apple juice and to compare it with the efficiency of a reference strain G. oxydans ATCC 621H. The highest antifungal activity of G. oxydans 1J was observed between days 3 and 9 with no colony growth, while on day 12, P. expansum colony diameter was reduced to 42.3 % of the control diameter. Although G. oxydans 1J did not fully inhibit mould growth, it showed a high level of efficiency and completely prevented patulin accumulation in apple juice., Tretiranje voća fungicidima, nakon berbe, uobičajeni je način suzbijanja plave plijesni. Međutim, propadanje voća može se spriječiti i upotrebom antagonističkih mikroorganizama, kao što je bakterija Gluconobacter oxydans. Svrha ovoga rada bila je izolirati prirodnu mikrobnu populaciju s površine jabuka i istražiti moguće inhibitorno djelovanje Gluconobacter oxydans 1J na plavu plijesan, Penicillium expansum, najvažnijeg uzročnika kvarenja jabuka u skladištu. Najveća antifungalna aktivnost bakterije primijećena je između 3. i 9. dana, kada nije zabilježen porast kolonija, a nakon 12. dana promjer kolonije plijesni bio je manji za 42,3 %. Iako istraživana bakterija Gluconobacter oxydans 1J nije u potpunosti inhibirala rast plijesni u jabučnom soku pokazala je visoku razinu učinkovitosti (od 86 % do 95 %). Gluconobacter oxydans 1J djelomično inhibira rast plijesni i u potpunosti biosintezu patulina, ovisno o vremenu i uvjetima uzgoja.

The aim of this study is to determine the effect of high intensity ultrasound (amplitude, temperature and treatment time) on the inactivation of food spoilage bacteria Escherichia coli 3014, Staphylococcus aureus 3048, Salmonella sp. 3064, Listeria monocytogenes ATCC 23074 and Bacillus cereus 30. The model suspensions of bacteria were treated with 12.7-mm ultrasonic probe operated at 600 W nominal power (ultrasonic treatment implemented at 20 kHz) and at amplitudes of 60, 90 and 120 µm. Also, treatment time of 3, 6 and 9 min and temperature of 20, 40 and 60 °C were used. The results were statistically processed with STATGRAPHICS Centurion computer program and response surface methodology. All three parameters studied seem to substantially affect the inactivation of bacteria in pure culture. The results also indicate increased inactivation of microorganisms under longer period of treatments, particularly in combination with higher temperature and/or amplitude. After ultrasonic treatment at 60 °C, 9 min and 120 μm, the viability of cells was not confirmed for Escherichia coli 3014, Staphylococcus aureus 3048, Salmonella sp. 3064 and Listeria monocytogenes ATCC 23074. Under the mentioned conditions the highest inactivation (3.48 log CFU/mL) of Bacillus cereus 30 was obtained., Svrha je ovoga rada bila utvrditi utjecaj ultrazvuka visokog intenziteta (velike amplitude, te pri višoj temperaturi i duljem vremenu obrade) na inaktivaciju bakterija što uzrokuju kvarenje hrane, i to: Escherichia coli 3014, Staphylococcus aureus 3048, Salmonella sp. 3064, Listeria monocytogenes ATCC 23074 i Bacillus cereus 30. Suspenzije bakterija tretirane su pomoću sonde promjera 12,7 mm, nominalne snage od 600 W (ultrazvučna je obrada provedena pri 20 kHz) sa tri amplitude (60, 90 i 120 µm), na temperaturi od 20, 40 i 60 °C, tijekom 3, 6 i 9 min. Rezultati su obrađeni programom STATGRAPHICS Centurion, pri čemu je korištena metoda odzivne površine, a utvrđeno je da sva tri ispitana parametra bitno utječu na inaktivaciju bakterija u čistoj kulturi. Rezultati pokazuju da je bolja inaktivacija mikroorganizama postignuta s duljim vremenom obrade ultrazvukom pri višim temperaturama i/ili većim amplitudama. Nakon ultrazvučne obrade na 60 °C i 120 µm tijekom 9 min potpuno su inaktivirane stanice bakterija Escherichia coli 3014, Staphylococcus aureus 3048, Salmonella spp. 3064 i Listeria monocytogenes ATCC 23074. Pri tim je uvjetima postignuta najveća inaktivacija bakterija Bacillus cereus 30 (3,48 log CFU/mL).

Zearalenone is mycotoxin harmful to the health of humans and animals and is present in food and feed. Therefore, last few decades, great attention is paid to the development of biological detoxification methods with reference to the application of lactic acid bacteria in binding and removal of mycotoxins from food and feed. The aim of this work was to investigate the ability of lactic acid bacteria Lactobacillus rhamnosus GG (ATCC 53103) and Lactobacillus plantarum A1 to bind zearalenone unto the cell surface. The results showed that Lactobacillus rhamnosus GG (ATCC 53103) and Lactobacillus plantarum A1 can bind signifi cant concentration of zearalenone, depending on the bacteria concentration in the medium and the incubation time. However, with longer time of incubation part of bounded mycotoxins were released back into the medium which indicates that the reaction of adhesion of toxin to the bacterial cells is reversible. Determination of zearalenone concentration was performed by competitive ELISA test.