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The aim of this study was to investigate the antifungal potential of onion (Allium cepa L. cultivar Kupusinski jabuar) essential oil against fungal species isolated from food. Twenty one compounds were identified in the onion essential oil and the major components were dimethyl-trisulfide (16.64%) and methyl-propyl-trisulfide (14.21%). Applied concentrations of onion essential oil (3.5, 7.0, 14.0, and 28.0 L/100 mL) caused the delay or absence of fungal growth with different inhibitory effects on the deceleration in the growth rate. Onion essential oil at a concentration of 28.0 L/100 mL demonstrated a fungicidal effect on the growth of Aspergillus carbonarius, Aspergillus wentii, Aspergillus versicolor, Penicillium brevicompactum, Penicillium glabrum, Penicillium chrysogenum, and Fusarium spp. and an inhibitory effect on Aspergillus niger and Penicillium aurantiogriseum. Macroscopic and microscopic investigations showed that the application of onion essential oil caused changes in macro-morphology and micro-morphology of the investigated fungi.

Preliminary examination of the antimicrobial activity of lactic acid against nine bacteria (Escherichia coli, Proteus mirabilis, Salmonella enteritidis, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Listeria monocytogenes, Bacillus cereus and Bacillus megaterium) and three yeasts (Rhodotorula sp., Saccharomyces cerevisiae and Candida albicans) was performed using disc diffusion and broth microdilution method. At a concentration of 321mg/mL, inhibition zones ranged from 24.0mm (Es.coli) to 38.3mm (En.faecalis) for the tested bacteria. The inhibition zones of the yeasts ranged from 11.3mm (Sac.cerevisiae) to 14.0mm (Rhodotorula sp.). Lactic acid minimal inhibitory concentration for bacteria was 1.25mg/mL, while minimal biocide concentration was 2.50mg/mL. Minimal inhibitory concentration for yeasts was 12.50mg/mL, while minimal fungicidal concentration was 25.00mg/mL. The obtained results showed that lactic acid could be used as an efficient natural antimicrobial agent improving the safety of all-natural foods. Practical ApplicationsConsumer perception that synthetic food additives may be associated with potential toxicological problems has recently generated interest for the use of naturally derived compounds in the food industry. The use of lactic acid is considered as a good alternative and may be more acceptable to consumers than synthetic food additives because of its natural origin, potential antimicrobial activity, as well as preservative, antioxidant, flavoring and acidifying properties as well as low cost. For ensuring food safety, combination of lactic acid with other natural antimicrobial agents or other preservation methods should be considered. Therefore, there is a potential for lactic acid usage in the development of eco-friendly technology which ensures food safety.

BACKGROUNDUtilization of wastes and industrial by-products for production of valuable bio-based chemicals has economic and environmental advantages. The aim of this study was to investigate utilization of two industrial by-products, distillery stillage and sugar beet molasses combined as a substrate for lactic acid and biomass production. A selection of the most appropriate lactic acid bacteria that could effectively utilize this waste substrate was performed. In addition, the effect of initial sugar concentration on lactic acid production and growth of lactic acid bacteria on the combined waste substrate was evaluated. RESULTSLactobacillus paracaseiNRRL B-4564 was selected as the most promising for lactic acid production on distillery stillage and sugar beet molasses. The highest lactic acid productivity of 1.42 g L-1 h(-1) and yield of 0.91 g g(-1) were achieved on stillage/molasses media at initial sugar concentration of 56.74 g L-1. The highest number of L. paracasei cells at 5.3 x 10(9) CFU mL(-1) was achieved at initial sugar concentration of 78.22 g L-1. CONCLUSIONCombined distillery stillage and sugar beet molasses could provide valuable nutrients for growth of fastidious lactic acid bacteria and enable efficient lactic acid production, while processing industrial waste in this way has great environmental relevance.

The article was aimed at investigating the antifungal activities of basil (Ocimum basilicum L.) extract against food spoilage fungi like Cladosporium cladosporioides, Emericella nidulans, Eurotium amstelodami, Eu. herbariorum, Eu. chevalieri and Eu. rubrum. At 7.0 mg/mL concentration, basil extract inhibited only the growth of C. cladosporioides. At 15.0 mg/mL concentration, the tested extract completely inhibited the growth of Em. nidulans, Eu. herbariorum, Eu. chevalieri and Eu. rubrum, while the growth of Eu. amstelodami was reduced by 42.1%. Applying the agar plate method, the strongest effect was exhibited against C. cladosporioides whereas Eu. amstelodami showed the lowest sensitivity to the applied extract. Higher extract concentrations (7.0 and 15.0 mg/mL) reduced growth of aerial mycelium in all tested species. The microscopic examination of the fungi confirmed the presence of hyphae deformations with a frequent occurrence of fragmentations and thickenings and diminished sporulation.

BACKGROUND: Bioethanol is mostly produced from starchy parts of the corn grain kernel leaving significant amounts of valuable by-products such as dried distillers' grains with solubles (DDGS) which can be used as a substitute for traditional feedstuff. The suitability of six maize hybrids from Serbia was investigated for bioethanol and DDGS production. The correlation between physical and chemical characteristics of the grain, bioethanol yield and quality of the corresponding DDGS was assessed. RESULTS: All hybrids had very different chemical composition and physical characteristics which could allow various applications. The highest bioethanol yield (94.5% of theoretical) and volumetric productivity (2.01 g l1 h1) were obtained with hybrid ZP 434 and the lowest with ZP 611k. Regarding chemical composition, all DDGS samples manifested good properties as feed components. Their protein content was higher compared to the kernel. In addition, the samples showed high digestibility and high mineral content, especially of calcium and phosphorus. CONCLUSION: A hybrid ZP 434 was selected as the most promising bioethanol producer. This property is attributed to the highest level of soft endosperm which is more susceptible to starch-hydrolysing enzymes. A high yield potential per hectare makes it the best candidate for commercial bioethanol production. (c) 2012 Society of Chemical Industry