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A serious global problem with the increasing resistance of microorganisms to currently used antimicrobials has opened up the promotional research in the identification of new, more effective drugs with a broad spectrum of antimicrobial activities. Plant essential oils, due to the large biological and structural diversity of their components, are known to have many potential benefits. This study aimed to evaluate the antimicrobial and anti-adhesion activity of fifteen essential oils and their compounds against two bacterial and two yeast species responsible for food spoilage and infectious diseases. Antimicrobial activity was determined by testing the minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) and the minimum fungicidal concentration (MFC) of essential oils and compounds. The essential oils of Cinnamomum zeylanicum and Eugenia caryophyllus showed the highest antimicrobial activity with MICs ranging from 0.078 to 1.25 mg/mL, and 0.039 to 1.25 mg/mL, respectively. On the other hand, essential oils of Eucalypti aetheroleum and Salvia officinalis had significantly weaker antimicrobial properties than the others. Further, MICs were used to assess the inhibition of adhesion of bacteria Salmonella Typhimurium ATCC 25923 and Staphylococcus aureus ATCC 14208, and yeasts Candida albicans ATCC 10231 and Saccharomyces cerevisiae ATCC 9763 in a microtiter plate using the crystal violet staining method. Based on the percentage of adhesion inhibition, yeast S. cerevisiae ATCC 9763 showed a high level of antimicrobial resistance. E. caryophyllus had the strongest effect with inhibition up to 73%. Consistent with the antimicrobial susceptibility results, the most active anti-adhesion compounds were carvacrol and thymol. Considering the role of biofilm in food spoilage and clinical diseases, inhibition of the initial phase of biofilm formation by natural antimicrobial agents may be an alternative to commonly used synthetic ones.

This paper aimed to review the publications on mycotoxins' presence in cereals and foodstuffs originated from the Serbian market covering the period from 2005 to 2022. The review covers all the important steps in mycotoxins analysis including sampling, sample preparation, instrumental analysis, and concentration ranges in which the mycotoxins were found. Also, the results were interpreted from the European Union regulation point of view. The review emphasizes the importance of multi-mycotoxins analysis for determining the simultaneous presence of mycotoxins that can negatively affect the Serbian human population. The most frequently used instrumental technique in the mycotoxin analysis of Serbian products was the Enzyme-Linked Immunosorbent Assay followed by the Ultra-High Performance Liquid Chromatography coupled with triple quadrupole mass spectrometry. Most of the studies undertaken in Serbia until now investigated a few groups of matrices such as wheat, maize, milk, and dairy products. Only a few studies involved specific matrices such as nuts, dried fruits, biscuits, cookies, and spices. The review showed that contamination of milk and dairy products with aflatoxin M1 (AFM1), occurred at the very beginning of 2013, was the major health issue related to the population health. The contamination of milk and dairy products with the AFM1 was a consequence of maize contamination with aflatoxins which occurred in the year 2012, characterized by drought conditions. The studies dealing with the analysis of masked and emerging mycotoxins are rare and more attention should be paid to monitoring the presence of these types of mycotoxins in foodstuffs from Serbia.

Apple pomace is a by-product of the apple processing industry and can be used for various uses such as animal feed, for composting, or to extract valuable compounds such as pectin or antioxidants. In recent years, it has also gained attention as a potential food ingredient due to its fibre content and antioxidant properties. The aim of this study was to examine the effect of three parameters: the percentage of wheat flour replaced by extrudate (5%, 10%, and 15%), the percentage of apple pomace in the extrudate (15%, 30%, and 45% based on the mass of corn grits), and the particle size of the extrudate (<250 µm; 250–1000 µm; 1000–2000 µm) on the properties of cookies, using the Box–Behnken experimental design. The addition of extrudates enriched with apple pomace significantly increased the total fibre and ash content of the cookies. The hydroxymethylfurfural content also increased, but not above the permitted limits (25 mg/kg). The sensory quality was strongly influenced by the particle size, especially the hardness, graininess, and appearance of the cookies. The addition of extrudate led to a darker colour of the cookies and a significant increase in the proportion of red tones, but generally had no negative influence on the acceptability of the cookies and their microbiological stability during the 6-month storage period. [ABSTRACT FROM AUTHOR]

This research examined the potential use of isolated Serbian autochthonous fungi in lignocellulosic biomass pretreatment. Among 12 isolated fungi, the isolates identified as Trametes hirsuta F13 and Stereum gausapatum F28 stood out as ligninolytic enzyme producers and were selected for potential use in the pretreatment of a waste lignocellulosic biomass. An isolate identified as Myrmaecium fulvopruinatum F14 showed high hydrolytic activity, but negligible ligninolytic activity, and it was selected as a potential producer of important industrial hydrolytic enzymes. Further, the breakdown of lignocellulosic waste, beechwood sawdust, by T. hirsuta F13 and S. gausapatum F28 was examined. Both isolates efficiently degraded biomass, but T. hirsuta F13 exhibited greater selectivity (selectivity coefficient of 1.7) than S. gausapatum F28 (1.1). The isolate F13 was considered a better candidate for the pretreatment, and it was selected for further analysis which involved the use of molasses stillage as a supplement to improve the pretreatment.

Brewer's spent grain (BSG) was used in this study as a support for the immobilization of Lactobacillus paracasei NRRL B-4564, thus enabling the recirculation of immobilized biomass in repeated-batch fermentation. The chemical composition and the energy parameters of the fermented and non-fermented BSG were analyzed and compared. Moreover, the probiotic features of L. paracasei were analyzed to examine the possibility of using fermented BSG as a functional ingredient in ruminant diets. The results obtained indicate that the fermented BSG had significantly higher protein and ash contents, as well as a significantly lower content of fiber fractions. Furthermore, the fermentation process increased the BSG energy content. The analysis of probiotic potential revealed a high tolerance of L. paracasei to pH 2.5 and bovine bile, autoaggregation ability and antimicrobial activity, suggesting that the fermented BSG with immobilized microbial biomass can be used as functional feed in ruminant diets.

This study aimed to test different chemical agents to obtain microbiologically safe industrial hemp seeds that could be used for further food processing (with the reduced total number of microorganisms, total number of moulds and yeasts, and total number of Enterobacteriaceae). In order to obtain seeds applicable for food consumption, optimal storage temperature conditions (room temperature, refrigerator, freezer), method of seed packaging (vacuum/without vacuum), and the application of various chemical treatments (ethanol, sodium hydrogen carbonate, sodium hypochlorite) were tested on the certified industrial hemp seeds, produced in two consecutive years. Optimal storage conditions differed for different microorganisms, and the most optimal storage was at room temperature, for seeds produced in 2018, in the treatment to reduce the total number of Enterobacteriaceae and the total number of microorganisms. When storing seeds from 2018 in order to reduce the number of yeasts and moulds, a slightly lower number was spotted when seeds were stored in a vacuum-sealed bag, at the refrigerator/freezer temperature. For hemp seeds produced in 2019, the most optimal storage conditions were at the refrigerator (for reduction of the total number of Enterobacteriaceae) and freezer temperature (for reduction of the total number of microorganisms). For the reduction of the total number of moulds and yeasts, optimal conditions were at room temperature. Ethanol (75%, v/v) was the most effective disinfectant among the tested chemicals regardless of the initial number of microorganisms, with log reduction of 3.2 (for the total number of Enterobacteriaceae), 2.9 log (for the total number of microorganisms), and total reduction of the total number of yeasts and moulds after 10 minutes, for the seeds harvested in 2019, which were far more contaminated than the seeds harvested in 2018. Considering the price of the disinfection method with ethanol, sodium hypochlorite may be a better solution for the reduction of the number of microbiota on the seeds.

In this study, moulds and mycotoxins presence in different tree nuts were investigated. The results showed that all of the 25 samples were contaminated with moulds. Mean values of total mould count varied from 1-4.9 cfu per grain. The most frequent species in hazelnut samples were Rhizopus oryzae (32.2%) and Aspergillus niger (28.9%). In walnuts A. niger (75.6%), in cashews also A. niger (42.4%) while in pistachio samples Alternaria alternata (20.7%), and Cladosporium cladosporioides (20.7%) were the most dominant. Rhizopus oligosporus was the only identified species in all almond samples (100%). Using Enzyme Linked Immunosorbent Assay (ELISA), the presence of total aflatoxins and ochratoxin A was examinated. In all analyzed samples, levels of ochratoxin A were below the limit of detection. Total aflatoxins were detected only in walnut samples with average concentration of 7.1 μg/kg.

The objective of this research was to determine chemical composition and to evaluate the antifungal activity of essential oil of Mentha piperita. By the application of GC/MS analysis of essential mint oil, 27 components were identified. The major components were menthol (39.9 %), menton (23.51 %), menthyl acetate (7.29 %), 1.8-cineol (5.96 %), isomenton (5.24 %), isomenthol (3.17 %), trans-caryophyllene (2.88 %), limonene (2.14 %), pulegon (1.38 %), beta-pinene (1.14 %) and piperiton (1.03 %). The quantitative structure– retention relationship (QSRR) was employed to predict the retention time (RT) of Mentha piperita essential oil compounds obtained in GC/MS analysis, using twelve molecular descriptors selected by genetic algorithm. The selected descriptors were used, as inputs of an artificial neural network, to build an RT predictive QSRR model. The coefficient of determination was 0.983, during training cycle, indicating that this model could be used for prediction of RT values for essential oil compounds in Mentha piperita essential oil extracts. Essential oil of Mentha piperita showed antifungal activity on all tested isolates in the minimal inhibitory concentration range of 0.2–1.7 μl/ml and a minimal fungicidal concentration (MFC) range of 1.7–454.5 μl/ml. The most powerful antifungal activity of mint was observed in C. cladosporioides of MFC value 1.7 μl/ml. P. aurantiogriseum showed the lowest sensitivity of MFC value 454.5 μl/ml. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 31029]

Antifungal and antimycotoxigenic activity of fullerenol nanoparticles (FNPs) were investigated on Aspergillus flavus growth isolated from a real food sample and aflatoxins (AFs) (AFB1 and AFB2) production. The final FNPs concentrations in in vitro and in commercial corn flour after the stationary incubation period of 7 and 14 days were in the range 0.16–80 µg/mL and 0.16–80 µg/g, respectively. Nanocharacterization of FNPs revealed an average size of 5–20 nm and a zeta potential of −35 mV. The highest degree of A. flavus mycelium growth inhibition (28%) after 7 days was observed for applied FNP concentration of 8.0 µg/mL, while after 14 days FNP concentration of 0.32 µg/mL led to the maximal inhibition of A. flavus mycelium growth (36%). Spearman's correlations analysis revealed a strong positive correlation between AFB1 and AFB2 concentrations in YES broth after 7 (R = 0.994, p < 0.05) and 14 days (R = 0.976), as well as between AFs concentrations and A. flavus mycelium mass after 7 (R = 0.786 for AFB1 and R = 0.766 for AFB2) and 14 days (R = 0.810 for AFB1 and R = 0.833 for AFB2). Paired samples t‐test showed the existence of a statistically significant difference (p < 0.05) between the produced AFs concentrations after the incubation of 7 and 14 days. Regarding the artificially inoculated corn flour the lower applied FNP concentrations (0.16–0.8 µg/g) achieved a reduction of AFB1 up to 42% and 60% after 7 and 14 days, respectively. [ABSTRACT FROM AUTHOR]

Stillage is a main by-product of the bioethanol industry and, depending on the origin of substrates for bioethanol production, it can be a significant pollutant affecting the profitability of bioethanol production. Directing the stillage towards the production of bio-based chemicals or high-quality feed is a preferred strategy. In this paper, a complete utilization of stillages of different origins was assessed. Thin stillages from bioethanol production from molasses, wasted bread and corn were chemically characterized, evaluated and compared as substrates for lactic acid (LA) and probiotic biomass production by Lactobacillus rhamnosus ATCC 7469, while solid fractions of wasted bread and corn stillages were analyzed for feed. The impact of pH control using CaCO3 or NaOH was also examined, both in terms of LA production and valorization of the remains generated in each process.A maximal LA productivity of 1.14 g/(L h) was obtained on thin wasted bread stillage with pH control by NaOH while the number of viable probiotic bacterial cells was above 109 CFU/mL. The composition of the solid fraction of the wasted bread stillage was complementary with the needs of monogastric animals, while the solid fraction of corn stillage was more adequate for the nutritional requirements of ruminants. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 31017]

In many parts of the world, the major cereal crops (maize, wheat, barley, rye and oats) are particularly susceptible to infection by Fusarium species. Moniliformin (MON) is a mycotoxin produced by Fusarium species, most often F. proliferatum, F. avenaceum and F. subglutinans. The occurrence of MON has been recorded worldwide, with the highest detected value of 530 mg/kg in maize intended for human consumption. Limited information on toxicity in experimental and farm animals indicates haematotoxicity and cardiotoxicity as the main damaging effects of MON on human health. Its stability and fate during processing has also been poorly studied, so the degree of consumer's exposure to MON is still uncertain. This review summarizes available information on the MON chemistry, toxicity, its worldwide occurrence in cereals, methods of analysis and the potential methods for its decontamination in food and feed.

The aim of this study was to assess utilization of distillery stillage in a two-stage fermentation using Bacillus licheniformis TFUNS and Lactobacillus paracasei NRRL B-4564. In the first stage the stillage was pretreated with B. licheniformis which is an efficient producer of proteolytic enzymes, in order to increase the content of free α-amino nitrogen in the waste substrate. In the subsequent stage the lactic acid (LA) fermentation by L. paracasei was performed. The results of the fermentation of proteolytically pretreated stillage (i.e. of two-stage fermentation) were compared with the untreated stillage (one-stage fermentation). The results have shown that the amount of free α-amino nitrogen in pretreated media was 107 % higher compared to the initial value. The concentration of the LA obtained in the second stage by L. paracasei was 48 % higher than in untreated stillage. In addition, the growth of L. paracasei in pretreated stillage was also better supported compared to that in untreated media. The process enabled economical and sufficient supply of easily assimilative nitrogen sources needed for lactic acid bacteria, thus avoiding addition of costly sources in the media commonly performed in LA production.

In the Western Balkans, traditional dry-cured sheep ham called Pastrma or Stelja is produced. Dry-cured sheep ham from Sjenica is produced in a very complex manner, and a prerequisite for its production is the sanitary safety of raw materials in accordance with veterinary and sanitary regulations. Isolation and preliminary identification of fungi from sheep ham were carried out in this study, as well as in vitro testing of the effects of water activity (aw) on the growth of isolated fungi. Fungi were isolated from 9 samples of dry-cured sheep meat taken from three households in the area of Sjenica in two productive years (2015 and 2016). Species of genus Penicillium were isolated as dominant in all the investigated samples. Water activity was tested on MY50GF agar from the series of malt extract yeast extract glucose fructose agar. Water activity was set to values of 0.87, 0.89, and 0.97. The results of the research showed that the growth of fungal colonies is under the direct influence of water activity. Fungi grew fastest at water activity of 0.97, and the highest growth of all tested species was recorded after 3 (A. niger), 7 (P. patulum), and 10 days (A. nidulans).

The objective of this study was to evaluate the possibility of application of two triticale varieties, NS Paun and Odisej, as partial substitutes for barley malt in wort production, based on the triticale analyses, micromalting, and analyses of the produced triticale malts, with a highlight on the activity of amylases during the malting process. The analyses of two triticale varieties showed higher extract content and diastatic power in comparison to barley malt. In the varieties NS Paun and Odisej, the extract was by 11.4% and 6.3% higher than the standard values for barley malt, respectively. Diastatic power in varieties NS Paun and Odisej was by 100% and 111.9% higher than in barley malt, respectively. In both varieties, α- and β-amylases activities were also high. The α-amylase activity increased during the micromalting 34 and 20 times, respectively, in comparison to native triticale grain. The β-amylase activity also increased during micromalting, but to a lesser extent. The produced triticale malts had good technological parameters and could be used as a partial substitute for barley malt in wort production. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-31066]

Lactic acid (LA) has gained considerable importance in the global market due to a wide range of applications. Because of the growing demand for food and feed, the use of lignocellulosic residues, by-products and waste streams is highly needed for commercial LA production. This study investigated the possibility of using potato stillage and sugar beet molasses for LA and biomass production by Lactobacillus paracasei NRRL B-4564 immobilized on sugar beet pulp. Adsorption of L. paracasei enabled easy separation of bacterial biomass from the fermentation media and its efficient reuse in three successive batch cycles. Total LA concentration of 146 g L-1 and average productivity of 1.03 g L-1 h-1 were achieved on waste substrate using bacterial cells immobilized on a natural carrier without mineral and nitrogen supplementation. The solid part of fermentation media remaining after LA fermentation is a valuable co-product, which could be used as animal feed rich in probiotic biomass.

In this study, carob pulp flour (CF) extract was characterized as a high-value antioxidant and antimicrobial agent. CF extracts were obtained using microwave-assisted extraction (MAE) and optimization of the MAE process was accomplished using response surface methodology. The studied processing parameters of MAE were the liquid/solid (L/S) ratio (10–30 mL/g), extraction time (15–35 min), and ethanol concentration (40–80% w/w). The efficiency of the extraction of valuable compounds from CF was evaluated by the determining extraction yield (Y), total phenolic(TP), total flavonoid (TF) content, and antioxidant activity (DPPH, FRAP, and ABTS). The optimized MAE parameters for maximizing the yields of target compounds and antioxidant activity were the L/S ratio 30 mL/g, extraction time 35 min, and ethanol concentration 40%. The experimentally obtained values for TP, TF, DPPH, FRAP, and ABTS were 1609.92 GAE/100 g, 271.92 CE/100 g, 99.02 µMTE/g, 50.45 µM Fe2+/g, and 110.55 µMTE/g, respectively. The optimized CF extract was compared with the CF extracts obtained by conventional solid–liquid extraction (S/L) and ultrasound-assisted extraction (UAE) and was found to be more beneficial due to a 30% higher yield of TP and TF and 30–80% higher antioxidant activity. The phenolic profiles of the three extracts were quite similar. The microdilution method confirmed the antibacterial activity of MAE and S/L extracts while the antifungal effect was not observed. [ABSTRACT FROM AUTHOR]

In this study, the stillage from the bioethanol production on wasted bread has been used as a substrate for fermentation by lactic acid bacteria. Ultrasound has been studied as a physical treatment of wasted bread stillage before fermentation by Lactobacillus rhamnosus ATCC 7469. In the ultrasound treated sample a 15 % higher lactic acid concentration compared to control sample and lactic acid yield of 0.87 g g-1 were obtained. Ultrasound could significantly increase LA productivity without effect on cell growth. Moreover, the number of viable L. rhamnosus ATCC 7469 cells was found higher in ultrasound treated samples. The study indicated that the ultrasound pretreatment could be effectively applied and used as an alternative to sterilization in lactic acid fermentation of distillery stillage.

Distillery stillage is abundant industrial waste with a great potential for utilization as a substrate in production of valuable bio-based products. Processing of distillery stillage on cost effective way can significantly decrease the price of bioethanol as alternative fuel and provide a considerable benefit to the environment. In this paper, combined potato stillage and sugar beet molasses substrate is evaluated for integrated lactic acid and probiotic biomass production by Lactobacillus rhamnosus ATCC 7469. Waste substrate based on potato stillage and sugar beet molasses enabled lactic acid and biomass production with maximal volumetric lactic acid productivity of 1.11 g L-1 h-1 and maximal number of viable L. rhamnosus ATCC 7469 cells of 1.1×109 CFU mL-1. Residue after removal of lactic acid could be recommended as probiotics and betaine-enriched animal feed.

Brewers' spent grain (BSG) hydrolysates were used for lactic acid (LA) fermentation by Lactobacillus rhamnosus ATCC 7469. The aim of this study was to evaluate possibilities of the BSG hydrolysate utilization as a substrate for LA fermentation as well as the effect of dry brewers' yeast addition in hydrolysate on lactic acid fermentation parameters (L-(+)-LA and reducing sugar concentration and number of viable cell-viability). Very high L. rhamnosus ATCC 7469 cell viability was achieved in all fermentations (9.26-9.52 log CFU/mL at the end of fermentation). L-(+)-LA concentration increased with an increase in brewers' yeast content in hydrolysate.

In line with the goals of sustainable development and environmental protection today great attention is directed towards new technologies for waste and industrial by-products utilization. Waste products represent potentially good raw material for production other valuable products, such as bioethanol, biogas, biodiesel, organic acids, enzymes, microbial biomass, etc. Since the first industrial production to the present, lactic acid has found wide application in food, cosmetic, pharmaceutical and chemical industries. In recent years, the demand for lactic acid has been increasing considerably owing to its potential use as a monomer for the production of poly-lactic acid (PLA) polymers which are biodegradable and biocompatible with wide applications. Waste and industrial by-products such are whey, molasses, stillage, waste starch and lignocellulosic materials are a good source of fermentable sugars and many other substances of great importance for the growth of microorganisms, such as proteins, minerals and vitamins. Utilization of waste products for production of lactic acid could help to reduce the total cost of lactic acid production and except the economic viability of the process offers a solution of their disposal. Fermentation process depends on chemical and physical nature of feedstocks and the lactic acid producer. This review describes the characteristics, abilities and limits of microorganisms involved in lactic acid production, as well as the characteristics and types of waste products for lactic acid production. The fermentation methods that have been recently reported to improve lactic acid production are summarized and compared. In order to improve processes and productivity, fed-batch fermentation, fermentation with immobilized cell systems and mixed cultures and opportunities of open (non-sterilized) fermentation have been investigated.

The cost of distillery wastewater treatment is an important issue in overall economy of bioethanol production. Besides traditional utilization of distillery wastewater or stillage in animal nutrition, its chemical complexity is offering other possibilities. Complete distillery wastewater and liquid stillage from bioethanol production were studied as substrates for batch, fed-batch and repeated batch lactic acid fermentation by Lactobacillus rhamnosus ATCC 7469 for parallel production of lactic acid, probiotics and feed. Both of the substrates, liquid stillage and complete stillage enabled effective production of lactic acid with the process productivity of approximately 1.80 g h-1L-1, however utilization of the remains was different. The first strategy enabled conversion of liquid distillery wastewater into lactic acid and high value feed additive with zeolite immobilized probiotic biomass. The second strategy enabled effective lactic acid production on the complete stillage with additional production of high quality fermented feed for monogastric animals.

In this study brewers' spent grain (BSG) hydrolysate was produced using optimal conditions. Hydrolysates were used for lactic acid fermentation by Lactobacillus rhamnosus ATCC 7469. The aim of this study was to evaluate possibilities of the BSG hydrolysate utilization as a substrate for lactic acid fermentation as well as the effect of dry brewers' yeast (1.0, 3.0, and 5.0 %) addition in hydrolysate on lactic acid fermentation parameters (L-(+)-lactic acid and reducing sugars concentration and number of viable cellsviability). Very high L. rhamnosus ATCC 7469cells viability was achieved in all fermentations (9.26-9.52 log CFU/mLat the end of fermentation). With the increase in brewers' yeast content in hydrolysate, L-(+)-lactic acid concentration increased. The highest L- (+)-lactic acid concentration and yield (89.01 %) were obtained in fermentation of hydrolysate with 5.0 % of brewers' yeast and 5.0 % of reducing sugars.