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The objective of this research was to isolate and identify lactic acid bacteria living in the digestive tract of the queen scallop Aequipecten opercularis and further test it as a probiotic culture on the growth of the bivalve during one month in captivity. Classic microbiological techniques (API and MALDI TOF) were used and four different strains of Lactiplantibacillus and one Lactococcus were identified and further analyzed, namely: Lactiplantibacillus plantarum I, Lactiplantibacillus plantarum 1, Lactiplantibacillus plantarum 2, Lactococcus lactis, and Lactiplantibacillus brevis. The isolated cultures were further tested for the highest antimicrobial activity towards the most common marine pathogens and survival at different temperatures and pH levels. The strain Lactiplantibacillus plantarum I had the best results, with the highest antimicrobial activity (77–85% pathogen growth inhibition) and the best safety standards showing no antibiotic resistance, and no ability to synthesize biogenic amine and degrade red blood cells. Considering all the abovementioned characteristics, the strain Lpb. plantarum I was further tested on the growth and health status of the bivalve Aequipecten opercularis during a month of cultivation in captivity. The results showed that the incorporation of Lpb. plantarum I led to a decrease in the quantity of test microorganisms in the bivalve and an increase in both the growth rate weight and growth rate length of the queen scallop A. opercularis. Furthermore, the scallops fed with the algae culture + Lpb. plantarum I gained significantly higher meat yield (33.15 ± 2.63%) compared with the control scallops fed only with the algae culture (29.66 ± 2.87%). To conclude, the results from this research indicate that including Lpb. plantarum I as a dietary supplement could enhance growth performance and serve as a feasible approach to reduce pathogen levels while cultivating A. opercularis in captivity.

Mikotoksini učestalo kontaminiraju hranu i hranu za životinje, prvenstveno žitarice i proizvode na bazi žitarica. Citrinin je mikotoksin kojeg sintetiziraju pojedine plijesni iz roda Penicillium, Aspergillus i Monascus, među kojima je P. citrinum njegov najznačajniji producent. S obzirom na nedostatnost podataka o razinama citrinina u žitaricama, u okviru ovog istraživanja analizirane se njegove koncentracije u kukuruzu (n=158) sa obiteljskih poljoprivrednih gospodarstava u Hrvatskoj tijekom petogodišnjeg razdoblja (2017.-2021.). Citrinin je detektiran u 25,3 % uzoraka kukuruza prikupljenih na području cijele Hrvatske tijekom petogodišnjeg razdoblja. Najveća prosječna koncentracija utvrđena je 2016. godine (162,9±162,0 µg/kg) te 2020. godine (154,9±358,8 µg/kg), a najveća koncentracija od 968,6 µg/kg određena je u 2020. godini u uzorku kukuruza uzorkovanom na području južne regije. S obzirom na utvrđenu značajniju kontaminaciju pojedinih uzoraka, može se zaključiti o nužnosti sustavnog nadzora citrinina u hrani i hrani za životinje, kao i definiranju najvećih dopuštenih količina ovog mikotoksina u okviru zakonodavstva.

Mikotoksini predstavljaju prirodne toksine koji učestalo kontaminiraju hranu i hranu za životinje, a primarno ih sintetiziraju plijesni iz rodova Aspergillus, Penicillium, Fusarium, Alternaria i Claviceps. Ove tvari predstavljaju vrlo stabilne spojeve, otporne na različite uvjete proizvodnje, prerade i skladištenja hrane. Mikotoksini mogu prouzročiti niz štetnih učinaka po zdravlje ljudi i životinja, tzv. mikotoksikoze, uključujući karcinogenost, mutagenost, genotoksičnost, imunotoksičnost, neurotoksičnost, hepatotoksičnost, nefrotoksičnost, te druge, pri čemu često istovremeno djeluju na više ciljnih mjesta u organizmu, u ovisnosti o toksičnosti samog mikotoksina te dozi i vremenu izloženosti. Za veliki broj mikotoksina još uvijek nema dovoljno dokaza o njihovim štetnim učincima na ljudsko zdravlje, ali se temeljem utvrđene osjetljivosti različitih životinjskih vrsta pretpostavlja da i u ljudi mogu izazvati slična djelovanja. Ujedno, za većinu mikotoksina koji se učestalo zajednički pojavljuju u hrani i hrani za životinje nisu razjašnjeni njihovi učinci u organizmu koji mogu varirati od antagonističkih do sinergističkih. Ovaj rad daje pregled mehanizama djelovanja mikotoksina od najvećeg javnozdravstvenog značaja i njihovih toksičnih učinaka u organizmu.

In the present work, the effect of high pressure processing (HPP) (0, 100, 200 and 300 MPa) and different treatment time (5 and 10 minutes) on the moisture uptake, cooking yield, colour and texture, as well as microbial population of chicken breast fillets was investigated. The application of high hydrostatic pressure resulted in a modification of quality parameters of chicken breast meat. By increasing pressure and time of the treatment the moisture uptake was reduced: samples treated with 300 MPa for 10 min had the lowest moisture uptake values. Cooking yield was not affected by HPP treatments. Increased pressure affected the colour by increasing L*, a* and b* values (only HPP treatment of 100 MPa in duration of 5 and 10 minutes did not affect colour of chicken breast meat). Lower pressures (100 and 200 MPa) tenderized, whereas elevated pressure (300 MPa) increased hardness in chicken breast fillets. Higher level of pressure (300 MPa) reduced bacteria count by about 3.0 – 5.3 log (CFU/g), depending on the microorganism and duration of the process.

Electrotechnologies gained increased popularity as non-thermal processing of foods as they offer many advantages over conventional thermal processing. These technologies effectively inactivate microorganisms, enhance the processing efficacy at lower treatment intensity (e.g. pressing, pre-treatment for drying, extraction etc.) with preservation of nutritional, functional and sensory characteristics of processed foods. Moreover, these technologies can be applied for targeted and controlled enzymatic treatments. Structural and conformational changes under these treatments may influence enzymatic inactivation, but also activate enzymes or enhance their activity. Therefore, the enzyme characteristics and treatment conditions could be finely tuned toward desirable properties and effects in food production and processing.

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.

Milk containing aflatoxin M1 (ATM1) in quantities above 0.05 µg/kg is considered unsuitable for consumption. It is possible to use mycotoxin deactivators that bind aflatoxin M1 and allow the further use of milk. The study aimed to examine the impact of selected mycotoxin deactivators (beta-glucan from yeast and oats, and live and dead lactic acid bacteria) on the nutritional composition of milk after binding to aflatoxin M1 intentionally added to milk. The study used consumption milk with 2.8% milk fat intentionally contaminated with aflatoxin M1. Furthermore, 0.05% and 0.1% solutions of beta-glucan from yeast and beta-glucan from oats were added to the contaminated milk, as well as live and dead lactic acid. Concentrations of Na, K, Mg, and Ca were monitored at the zero hour of binding of mycotoxin deactivators and ATM1, after 2 h of binding, and after 4 and 24 h of binding. The largest deviations were found in Na, K, and Mg, while the minimum changes were observed in Ca. Live lactic acid bacteria were found to have the least impact on micronutrients, except in Na (difference = 40, p = 0.029, GES = 0.083), where the 0.1% solution from oats had the least impact on micronutrient content. The results of this study suggest that it is best to use live lactic acid bacteria where the different duration of action regarding nutrients, with the possible exception of Na, is not relevant, which indicates that, when using this mycotoxin deactivator, milk contaminated with ATM1 can be further used.

During ripening, the surface of dry traditional meat products (TMPs) becomes overgrown by fungi of the Penicillium spp., Aspergillus spp. and Eurotium spp. whose spores mostly come from the environment in which the ripening chambers are placed. Certain fungi species is often responsible for the occurrence of toxic compounds termed the mycotoxins, among which of the outermost importance in connection with meat products are aflatoxin B1 (AFB1) and ochratoxin A (OTA). Besides, some other mycotoxins such as citrinin (CIT), cyclopiazonic acid (CPA) and sterigmatocystin (STC) can also be present, but their impact on the quality and safety of meat products, and therefore also on human health, has still not been fully clarified. As control and prevention of toxicogenic fungi growth are key factors to the prevention of mycotoxin presence in dry-cured TMPs, levels of mycotoxin contamination, mycotoxin-producing mould species and factors of relevance for mycotoxin production, such as climate, should be determined.

Cilj ovoga istraživanja bio je odrediti parametre kvalitete svježeg pilećeg mesa nakon tretmana ultrazvukom visokog intenziteta. Rezultati su pokazali da ne postoji značajna razlika u ukupnom broju bakterija između tretmana u ultrazvučnoj kupelji kroz 5 i 15 minuta u ispitanim uzorcima pilećeg mesa te da tretman ultrazvukom nema trajan učinak na uništavanje bakterija u pilećem mesu. Nasuprot tomu, funkcionalna svojstva pilećeg mesa su poboljšana tretmanom ultrazvukom u trajanju od 5 minuta pri frekvenciji 37 kHz, snazi 380 W i amplitudi 100%.

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.

Research background. Cheese in a sack is a traditional cheese produced in Croatia. Types of cheese with similar production technology are made in other countries but chemical and microbiological composition varies between regions. Traditionally, cheese in a sack is produced without the addition of starter cultures. Addition of beneficial probiotic cultures to numerous dairy products has documented advantages. Effects that the addition of probiotic bacteria to traditional cheese have on aroma compounds and sensory properties have not been fully investigated. The aim of this study is to determine the sensory properties and differences in the aromatic profiles between cheese samples ripened in a lambskin sack, produced traditionally without the addition of any starter culture, or with the addition of probiotic bacteria. Experimental approach. In this study, cheese in a sack was produced with the addition of probiotic cultures Lactobacillus plantarum B and L. lactis ssp. lactis S1. During ripening volatile aroma compounds were analysed with a solid-phase microextraction gas chromatography-mass spectrometry. Sensory properties were evaluated by trained tasters who are familiar with the traditional taste of the cheese from a sack. The results of aroma composition and taste scores were then compared using factorial and principal component analyses. Results and conclusions. Chromatography showed differences in the composition of aroma compounds and the sensory properties between the cheese produced with Lactobacillus starter cultures and the control cheese, traditionally produced without a starter culture. The addition of probiotic cultures L. plantarum B and L. lactis ssp. lactis S1 resulted in products with better sensory properties and chemical profile of volatile aromatic compounds. Novelty and scientific contribution. This study investigates the usage of naturally present probiotic cultures as starter cultures in cheese in a sack production. Their effects on aroma profiles and sensory characteristics have been compared for the first time using factorial and principal component analyses.

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.

Mikotoksini su sekundarni metaboliti toksikotvornih plijesni te su česti kontaminanti raznih prehrambenih proizvoda. Pojava aflatoksina M1 (AFM1) u mlijeku, prijetnja je zdravlju potrošača, posebice maloj djeci te dovodi do ekonomskih gubitaka zbog zbrinjavanja kontaminiranog mlijeka. Metode uklanjanja i/ili redukcije mikotoksina koje se koriste u prehrambenoj industriji troše velike količine energije i kemijskih sredstava, stoga biološke metode sve više dobivaju na značaju zbog svoje netoksičnosti i ekološkog aspekta. Cilj ovog rada je bio odrediti količinu nevezanog AFM1 nakon uklanjanja kompleksa β-glukan-AFM1 pomoću Centricon 70 Plus, MWCO 100 kDa filtera. U radu je upotrijebljen komercijalni β-glukan dobiven iz zobi i β-glukan izoliran iz biomase kvasca. Rezultati istraživanja ukazuju da je nakon uklanjanja kompleksa β-glukan-AFM1 u uzorku mlijeka zaostalo 35% AFM1 u slučaju kada je β-glukan dobiven iz zobi, odnosno 36,4% AFM1 kada je β-glukan izoliran iz kvasca.

The aroma of a cheese is one of the key quality parameters and signs of distinguishing certain cheese types by consumers. Therefore, the aim of this paper is review the existing knowledge of the aromatic profile of cheeses ripening in an animal skin. Cheeses that ripen in an animal skin and produced in similar technology in Croatia (mišina cheese in a sack), in Bosnia and Herzegovina (Cheese in a sack (local name: mjeh), Montenegro (Cheese in a sack (local name: mjeh), Turkey (Tulum cheese), Lebanon (Darfiyeh cheese) and eastern Algeria (Bouhezza cheese). The specific characteristic of these cheeses is ripening in an animal skin, as in a sack (of ewe or goat). The aromatic profile of these cheeses has not been sufficiently investigated and has been conducted primarily on Tulum and to a smaller extent of Lebanese Darfiyeh cheese, and cheese in a sack. There is no data about other cheeses that ripen in an animal skin. Since very little research has been made on the aromatic profile of these cheeses, further research should be conducted., Aroma sira jedan je od ključnih parametara kvalitete i znakova raspoznavanja pojedine vrste sira od strane potrošača. Stoga je cilj ovog rada pregled postojećeg znanja o aromatskom profilu sireva, koji se proizvode na tradicionalan način i zriju u životinjskoj koži. Sirevi, koji zriju u životinjskoj koži i imaju sličnu tehnologiju, proizvode se u Hrvatskoj (Sir iz mišine), na području Bosne i Hercegovine (Sir iz mijeha), Crne Gore (Sir iz mijeha), Turske (Tulum sir), Libanona (Darfiyeh) i istočnog Alžira (Bouhezza sir). Specifičnost ovih sireva je zrenje u životinjskoj koži, odnosno mišini (ovčjoj, kozjoj). Aromatski profil navedenih sireva je slabo istražen, a istraživanja su najvećim dijelom provedena na Tulum siru i manjim dijelom na libanonskom Darfiyeh siru, siru iz mišine, dok za ostale sireve,koji zriju u životinjskoj koži nema nikakvih podataka. Obzirom da je vrlo malo istraživanja o aromatskom profilu ovih sireva do sada napravljeno, potrebno je provoditi daljnja istraživanja u ovom pravcu.

This study focused on monitoring changes in aflatoxin M1 (AFM1) concentrations during produc- tion and storage of different fermented milks using selected probiotic and nonprobiotic combined cultures. Milk samples intended for fermentation were intentionally contaminated by adding a stan- dard of AFM1. All of the tested cultures caused remarkable reductions in AFM1 concentrations during the fermentation process. Probiotic cultures were more effective than nonprobiotic cultures, with Lactobacillus casei LC-01 strain being the most efficient, achieving a reduction level of approximately 58%. Among the nonprobiotic cultures, yoghurt culture YC- 380 was the most effi- cient, with a reduction level of approximately 41%.

The aim of this study was to investigate into the occurrence of deoxynivalenol (DON) and zearalenone (ZEN) in unprocessed cereals and soybean sampled in 2014 and 2015 from different fields located in Croatian regions. A total of 306 samples were analyzed for DON and 415 samples for ZEN concentrations using quantitative ELISA methods. In 2014, DON and ZEN were determined in all samples in the mean concentrations of 1, 461 ± 2, 265 µg/kg and 656 ± 853 µg/kg, respectively, while in 2015 these means were 2, 687 ± 2, 731 µg/kg and 1, 140 ± 1, 630 µg/kg, respectively. The cultivation year significantly (p < 0.05) influenced mycotoxin concentrations, whereas the influence of cultivation region was seen with ZEN for all cereals except soybean, and not seen with DON at all. A higher contamination determined during 2015 could be explained by high to extreme humidity evidenced in the period of cereals’ growth and harvesting.

Tijekom posljednjeg desetljeća znanstvenici sve više ukazuju na globalno zagrijavanje, dovodeći klimatske promjene u poveznicu s novom strukturom vrsta plijesni producenata mikotoksina po geografskim područjima svijeta. Izraženije klimatske promjene mogu u budućnosti izmijeniti otpornost domaćina i interakciju domaćin-patogen te imati znatan utjecaj na razvoj toksikogenih plijesni i produkciju mikotoksina kao njihovih sekundarnih metabolita. Novonastala klimatološka situacija izaziva sve veću pozornost i zahtijeva nove dijagnostičke alate, kao i nove spoznaje o biološkim karakteristikama poljoprivrednih kultura koje se uzgajaju i genetici toksikogenih plijesni. Zbog sve povoljnijih klimatskih uvjeta za rast Aspergillus flavus na području Europe, u narednom razdoblju postoji povećani rizik od onečišćenja žitarica izrazito toksičnim aflatoksinima. Ujedno, profil mikotoksigenih vrsta Fusarium počinje se sve znatnije mijenjati, a posebno je zabrinjavajući porast onečišćenja s F. graminearum u sjevernom i središnjem dijelu Europe. S obzirom na očigledne klimatske promjene, potrebna su daljnja istraživanja koja uključuju „prediktivne modele“ s više varijabli, a koji bi u bliskoj budućnosti omogućili kvalitetni pristup strategiji prevencije kontaminacije toksikotvornim plijesnima i mikotoksinima u hrani i hrani za životinje., Over the last decade, scientists have increasingly pointed to global warming, linking climate change to a new structure of mycotoxin-producing mould species across the world. In the future, more pronounced climate changes may alter host resistance and host-pathogen interaction, and have a significant impact on the development of toxicogenic moulds and the production of mycotoxins as their secondary metabolites. The newly emerging climatological situation is attracting increasing attention, demanding new diagnostic tools and new insights into the biological characteristics of cultivated crops and the genetics of toxicogenic moulds. In Europe, the climate conditions are highly favourable for the growth of Aspergillus flavus, bringing increased future risk of contamination of cereals with highly toxic aflatoxins. Meanwhile, the profile of mycotoxigenic species of Fusarium is beginning to change significantly, and increased reports of contamination with F. graminearum in northern and central Europe are particularly worrisome. Given the obvious climate change, further research is needed that will include predictive models with several variables, to provide an appropriate future approach to the strategy of preventing contamination by toxic moulds and mycotoxins in food and feed.

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.

The aim of this study was to investigate the occurrence of citrinin in different cereals (n = 341) and feedstuffs (n = 67) coming from farms and feed factories established in Croatia and Bosnia & Herzegovina. The highest mean citrinin concentration (103 ± 102 µg/kg) was observed in cereals sampled in Bosnia & Herzegovina during 2014, although significantly different levels between the two countries were not observed. Across the cereal samples, the maximal citrinin concentration was determined in wheat (429 µg/kg), while across the feedstuffs, the highest concentration was found in pig feed (63 µg/kg). Despite of the increased citrinin levels found in some samples, especially wheat, the obtained values cannot be compared against the maximum limits, since no such levels are stipulated under the applicable legislation. But, given that data on citrinin are very scarce, they can serve as an indicator of cereal and feed contamination in this part of Europe.

Traditionally, equid milk has been used as an alternative to human milk for infants or children mainly because of its similarities in nutrient composition, hypoallergenicity, immune modulation and antimicrobial activity. As a highly nutritious substrate, it possesses great potential for probiotic bacteria isolation. The aim of this study was to assess the probiotic potential of Lactobacillus plantarum M2 and L. plantarum KO9 isolated from donkey and mare milk, respectively, and determine TNF-α suppression attributed to their extracellular metabolites in lipopolysaccharide- (LPS-)stimulated human peripheral blood mononuclear cells (PBMCs). Resistance to simulated gastric and intestinal conditions, antimicrobial activity against pathogens, autoaggregation, coaggregation, biofilm quantification, antioxidative potential and haemolytic activity were determined. The isolated strains demonstrated great probiotic potential and their extracellular metabolites with molecular mass smaller than 2000 Da supressed TNF-α production up to 67% in LPS-stimulated PBMCs exerting high anti-inflammatory activity. Extracellular metabolites did not show any cyto/genotoxic effects toward PBMCs.

Toxicity of gamma irradiated mycotoxins aflatoxin B

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.