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Mikotoksini su toksični sekundarni metaboliti filamentoznih plijesni s dokazano negativnim učincima na zdravlje. Mikotoksini mogu kontaminirati hranu i poljoprivredne proizvode u bilo kojoj fazi proizvodnje, tijekom prerade, transporta ili skladištenja. Fumonizin B1 najčešće se pojavljuje u kukuruzu i kukuruznim proizvodima koji su uključeni u prehanu peradi. Postojeće metode uklanjanja dijele se na fizikalne, kemijske i biološke, međutim nisu u potpunosti efikasne ili njihova primjena u industriji nije praktična. Biosorpcija je novi način uklanjanja mikotoksina koji nudi visoku selektivnost i specifičnost, nisku cijenu i ekološki je prihvatljiv. Stoga su u ovom istraživanju kao biološki adsorbensi ispitane kosti i ljuske brancina i orade te njihova sposobnost vezanja FB1 u dvije vrste pufera te u simuliranim uvjetima gastrointestinalnog trakta peradi. Sva tri adsorbensa pokazala su dobro vezanje FB1 u fosfatnom (pH 7) i citratnom puferu (pH 3), dok je u simuliranim uvjetima probavnog trakta peradi zabilježena niža adsorpcija, što ukazuje na potrebu za daljnjim istraživanjima i modifikacijom adsorbensa. Dobiveni rezultati nude značajan doprinos u istraživanju uklanjanja mikotoksina te održivosti gospodarenja ribljim otpadom.

Research background. While it is clear that SARS CoV-2 coronavirus is the primary respiratory virus, there are no entirely clarified ways of transmission. Foodborne transmission has remained an unexplained path. Therefore, the goals of this paper are to examine and present an assessment of the most appropriate of the four selected kits for RNA extraction for the testing and detection of SARS-CoV-2 on food packaging surfaces, food surfaces, and in food. This will enable to indicate the possibility of infection through contact or direct food consumption. Experimental approach. Finding the best technique is vital as RNA extraction is one of the essential elements in detecting SARS-CoV-2. This was achieved through an experiment with four commercial kits following the original manufacturers’ protocols, and with a modification of the original protocols that included the use of ethanol and isopropanol. The selected kit was used for RNA extraction from the swabs of packaging surfaces, food surface, and ready-to-eat food samples. The coronavirus was then identified using real-time reverse transcription-polymerase chain reaction (RT-PCR) assays to determine whether the SARS-CoV-2 virus or viral particles are present in the food chain with the overall purpose of demonstrating the possibility that food can contribute as a vehicle for the transmission of the virus. Results and conclusions. The findings of this investigation made the most effective extraction kit and protocol stand out. The results of the applicability of the kit indicated a significant share of positive samples of viral SARS-CoV-2 virus particles on surfaces from the environment where infected persons with 'silent' COVID-19 infection, with mild symptoms or no symptoms, were present. However, according to the findings of the second part of the study, the virus was not detected on the examined samples of food packaging surfaces, food surfaces, and food. Novelty and scientific contribution. The presented results distinguished one of the most suitable protocols for isolating RNA from environmental surface samples. The main contribution of the study is in the presentation of the results, that is, the examination of samples that are primarily related to the food chain, food packaging, food surfaces, and ready-to-eat food. The results of this study could also be helpful for further determination of the potential of food as a vector for the transmission of coronaviruses., Pozadina istraživanja. Iako je jasno da je SARS CoV-2 koronavirus primarno respiratorni virus, nisu u potpunosti razjašnjeni načini njegovog prijenosa. Prijenos hranom je ostao neobjašnjen način prijenosa. Stoga su ciljevi ovoga rada bili ispitati i procijeniti koji je od četiri odabrana komercijalna kompleta za ekstrakciju RNK najprikladniji za testiranje i otkrivanje SARS-CoV-2 na pakiranjima, površini hrane i u hrani. Time bi se mogla utvrditi mogućnost infekcije kontaktom ili izravnom konzumacijom hrane. Eksperimentalni pristup. Pronalaženje najbolje tehnike je ključno, jer je ekstrakcija RNK jedan od bitnih elemenata u otkrivanju SARS-CoV-2. To je postignuto eksperimentom s četiri komercijalna kompleta za ekstrakciju, korištenih u skladu s izvornim protokolima proizvođača i njihovom modifikacijom koja je uključivala upotrebu etanola i izopropanola. Odabrani komplet korišten je za ekstrakciju RNK iz briseva s površina pakiranja, površine hrane i iz uzoraka gotove hrane. Koronavirus je zatim identificiran pomoću testova lančane reakcije polimerazom s reverznom transkripcijom u stvarnom vremenu (real-time RT-PCR), radi utvrđivanja prisutnosti virus SARS-CoV-2 ili virusnih čestica u prehrambenom lancu, sa sveukupnom namjerom dokazivanja mogućnosti prijenosa virusa putem hrane. Rezultati i zaključci. Rezultati ovog istraživanja istaknuli su najučinkovitiji komplet i protokol za izolaciju. Ispitivanjem primjenjivosti kompleta utvrđen je značajan udjel uzoraka pozitivnih na virusne čestice SARS-CoV-2 izdvojenih s površina iz radnog okoliša u kojem su boravile oboljele osobe s 'tihom' infekcijom COVID-19, odnosno s blagim simptomima ili bez simptoma bolesti. Međutim, prema nalazima drugog dijela istraživanja, virus nije detektiran na ispitanim uzorcima pakiranja hrane, površina hrane i hrane. Novina i znanstveni doprinos. Predstavljeni rezultati istaknuli su jedan od najprikladnijih protokola za izolaciju RNK iz okolišnih uzoraka površina. Glavni doprinos studije je u prikazu rezultata, odnosno ispitivanju uzoraka koji se primarno odnose na prehrambeni lanac, ambalažu hrane, površine hrane i gotovu hranu. Rezultati ove studije također bi mogli pomoći daljnjem određivanju potencijala hrane kao vektora za prijenos koronavirusa.

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.

Oxidative stress is characterized by the inability of the organism to detoxify reactive oxygen species (ROS) and can be defined as a condition in which the balance between prooxidants and antioxidants in the cell is disturbed, leading to DNA hydroxylation, protein denaturation, lipid peroxidation, and cell apoptosis. The antioxidant effects of probiotic cells and probioticenriched foods have been previously noticed, but the exact mechanisms of antioxidant action are not fully understood. Literature suggests that probiotic therapy improves host oxidative status, which may lead to prevention of some chronic diseases. The concept of paraprobiotics has been proposed to refer to the use of inactivated microbial cells or cell fractions that provide health benefits to the host. Hence, we aimed to exert H2O2-induced oxidative stress on isolated human lymphocytes and investigate the protective effect of heat killed probiotic bacteria Lactiplantibacillus plantarum S1 and extracted bacterial metabolites smaller than 2.000 Daltons on nuclear DNA of isolated lymphocytes, using the comet assay. Both, metabolites and heat killed cells significantly reduced the H2O2-induced DNA damage (from 7.59±1.51% in induced stress to 4.07±1.61% for metabolites and 3.86±1.58% for heat killed cells), displaying a protective role. In combined treatment of heat killed cells and metabolites, the DNA damage was significantly lower (2.62±1.02%) than oxidative stress sample and the levels of primary DNA strand breaks did not differ compared to control sample (1.33±0.14%). Probiotic metabolites and heat-killed cells could potentially be used in a modified model to reduce the adverse effects associated with oxidative stress in the lower parts of the gastrointestinal tract.

Znanstvene spoznaje i tehnološka dostignuća potaknuli su rast probiotičkog tržišta te se uz usmjeravanje prema personaliziranim pristupom u medicini pojavila i potreba za razvojem novih probiotičkih proizvoda s ciljanim učincima na zdravlje i stjecanjem novih spoznaja na području probiotika kako bi se bolje razumjeli mehanizmi interakcije korisnih mikroorganizama i domaćina. Globalno tržište probiotika u stalnom je porastu i pretpostavlja se da će se stopa rasta dodatno povećati u društvu pogođenom COVID-19 pandemijom. Usmjerenje probiotičke karakterizacije s ciljem pronalaska sojeva koji ispoljavaju određene korisne učinke te njihovo uklapanje u probiotičke proizvode spona je između klasične probiotičke terapije i ciljane, personalizirane primjene jer omogućuje selekciju korisnih učinaka ovisno o potrebi potrošača.

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.

The beneficial effects of probiotics on host health have been widely documented. Although the market is flooded with probiotic products, studies often show that the available probiotic strains do not meet the requirements for probiotics. One of the main criteria is a high survival rate during passage through the host gastrointestinal tract in order to exert beneficial effects at the target site. Because probiotics must survive these stressful conditions, techniques that protect the cells with non-toxic biopolymers are often used. An example of the use of such a matrix is microencapsulation in an alginate carrier. In addition, it is important to extend the shelf life of probiotic products. Therefore, freeze-drying techniques are used to allow longer storage. In addition to basic probiotic properties, certain functional properties are often desired. For example, recent studies recommend the consumption of products with high antioxidant potential, as they have many beneficial effects on health. In this work, probiotic bacteria (Lactobacillus plantarum M2 and Lactobacillus plantarum KO9) were encapsulated and freeze-dried. Freeze-dried microcapsules of these strains showed a high survival rate under simulated gastrointestinal tract conditions and were a suitable carrier for L-ascorbic acid, which increased the antioxidant capacity of the final product. The basic antioxidant activity of formed capsules, expressed as the ability to remove DPPH radicals, was determined. Since L-ascorbic acid has potential antimicrobial activity, its effect on the growth of selected pathogenic bacteria, such as Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes was investigated. This study shows how microencapsulation of probiotics with the addition of desired biological molecules can enhance the beneficial functional properties of probiotics.

Research on mycotoxins in traditional meat products (TMPs) conducted insofar has mostly been focused on ochratoxin A (OTA) and aflatoxin B1 (AFB1), while data on citrinin (CIT), sterigmatocystin (STC) and cyclopiazonic acid (CPA) prevalence and surface moulds producing these mycotoxins are still insufficient. This study aims at identifying toxicogenic mould species overgrowing the surfaces of the most prominent Croatian TMPs (n = 120). Moulds were identified using molecular techniques (Polymerase Chain Reaction, PCR) ; on top of that, genes responsible for mycotoxin production were pinpointed. Concentrations of mycotoxins were determined using liquid chromatography tandem mass spectrometry (LC-MS/MS). From the product surfaces, a total of 390 Penicillium, 98 Aspergillus and 13 Mucor isolates were retrieved, out of which some (Aspergillus niger, Aspergillus ochraceus and Penicillium verrucosum) toxicogenic. In total, mycotoxin presence was determined in 14% of samples, with the highest occurrence of OTA, present in significantly higher concentrations in hams than in dry-fermented sausages. The results also show random contamination with other investigated mycotoxins, indicating that household-based meat products’ production should run under standardized conditions with permanent control of surface mould growth during ripening.

The human exposome represents an intriguing gene-environment interactions. Since the food is one of the most easily manageable human exposure, the serach for food items that might have beneficial properties to human health is of high importance. This study aimed to assess the probiotic potential and the antioxidant properties of a new indigenous probiotic bacteria isolated from equid (ili donkey) milk, known for its beneficial properties for ages. DPPH scavenging ability of live cells was determined and compared to antioxidant standard (L-ascorbic acid). Furthermore, the antioxidant activity of extracellular bacterial metabolites, with molecular mass smaller than 2000 daltons (Da) that can cross the epithelial barrier was assessed accompanied by the investigation of cytotoxic and genotoxic effect of metabolites on peripheral blood lymphocytes. The battery of tests showed excellent probiotic potential. The DPPH free radical scavenging activity of L. plantarum M2 cells was 7.25%. The tested bacterial media fraction removed 4.84% for L. plantarum M2 and L-ascorbic acid (20 mg/L) as a positive standard removed 56.41% of free radicals. Examined metabolites exhibited no cytotoxic effects on peripheral blood mononuclear cells which was detected by acridine orange/ethidium bromide vital staining compared to controls. The results of comet assay also did not show inducton of primary DNA damage of peripheral blood mononuclear cells exposed to bacterial extracellular metabolites. Taken together, we managed to present a new bacteria from donkey milk with excellent probiotic potential. Furthermore it does not posses any toxic properties so we confirmed Qualified Presumption Safety Status. The next steps in research will try to elucidate its possibility of minimising effects of mutagens found in food.