The antifungal activity of monoacylglycerols with 8, 10 and 12 carbon chains (1-monocaprylin, 1-monocaprin and 1-monolaurin) against filamentous fungi isolated from contaminated bread (Penicillium piceum, Penicillium chrysogenum, Penicillium sp. and Monascus ruber) as well as against the selected microorganisms (Aspergillus niger, Penicillium roqueforti, Penicillium jensenii, Alternaria sp. and Phoma sp.) was investigated. All the tested monoacylglycerols showed antifungal efficacy at concentrations equal to or higher than 32.5 mg/L. Monolaurin shows a better inhibition effect against M. ruber, and the growth of Penicillium species was better inhibited with monocaprin and monocaprylin. Application of aqueous solutions of monoacylglycerols on the surface of freshly baked bread prevents its deterioration for at least 14 days, even during the storage in an environment strongly contaminated with tested microorganisms. Protection of bread loaf surfaces using monoacylglycerols solutions seems to be suitable procedure for treatment of bakery products with a prolonged storage period.

The aim of this study was to monitor the antibacterial effect of seven phosphate salts on selected strains of Gram-negative and Gram-positive bacteria, which could be considered responsible for food-borne diseases (Bacillus cereus, Bacillus subtilis, Enterococcus faecalis, Micrococcus luteus, Staphylococcus aureus, Citrobacter freundii, Escherichia coli, Proteus mirabilis, Salmonella enterica ser. Enteritidis and Pseudomonas aeruginosa). For these purposes, phosphates differing in chain length were used. The tested concentrations were in the range of 0.1-2.0% (wt v(-1)) applied at the model conditions. In the majority of cases the visible inhibitory effect on the growth of observed microorganisms could be seen. Due to the chemical structure of salts and their dissociation both the pH values of cultivation broth and similarly the growth characteristics of bacterial strains were affected. The inhibition of above mentioned bacteria was apparently supported by this dissociation. Phosphates obviously made the development of most Gram-positive bacteria impossible. Especially Micrococcus luteus was extremely sensitive to the presence of these substances. On the other hand, Gram-negative bacteria seemed to be resistant to the phosphate incidence. The exemption clause from the tested salts was represented by a high alkaline trisodium phosphate. It should be pointed out that generally the most significant antibacterial effects were shown by polyphosphates HEXA68 and HEXA70, trisodium phosphate undecahydrate, tetrasodium pyrophosphate and finally trisodium phosphate. By comparing the inhibitory effects of various phosphate salts can be concluded that the antibacterial activity was not determined only by the condensation degree but there was also proved the dependence on pH values.

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The efficacy of a new antimicrobial treatment of textile materials based on the use of 1-monocaprylin against various species of saprophytic moulds (Alternaria alternate CCM F-397, Aspergillus niger ATCC 16404, Mucor racemosus CCM 8190, Penicillium ochrochloron CCM F-158, Trichoderma viridae CCM F-728), pathogenic moulds (Epidermophyton floccosum CCM 8339, Trichophyton mentagrophytes ATCC 9533, Trichophyton rubrum DSMZ 4167), pathogenic yeasts (Candida albicans ATCC 10231, Candida parapsilosis CCM 8260), Gram-negative bacteria (Escherichia coli ATCC 11229, Klebsiella pneumoniae ATCC 4352) and Gram-positive bacteria (Staphylococcus aureus ATCC 6853) was investigated. The testing was carried out according to DIN EN ISO 20645 disc-diffusions test, using a 2-layer method. The results showed that 1-monocaprylin effectively killed all tested bacterial strains and pathogenic microorganisms with an exception of saprophytic moulds only, which were partially resistant. Textiles treated with 1-monocaprylin reduced the growth of pathogenic, potentially dangerous microorganisms frequently occurring for example on the feet and in the shoes.Practical applications: To prevent microbial contamination leading to degradation of textile materials, various antimicrobial agents aimed at killing or suppressing of microorganism growth are applied. Among others, also MAGs belong to safe and efficient antimicrobial agents. Their application in antimicrobial treatment of textiles may be a suitable alternative to commercially used antimicrobial agents, as these endogenous lipid substances are present almost in all animal and plant tissues and are harmless to human body. The present study has confirmed that MAGs possess a suitable inhibitory activity when applied on textiles and are capable of hindering and even suppressing growth of bacteria and moulds that may occur during storage and use of textiles. The obtained results can be closely related to potential industrial applications of MAGs as effective agents for antimicrobial textiles and lining and insole materials for footwear, including those designed for diabetics.

The effect of pressure and temperature on the flow properties of the materials intended for Powder Injection Moulding (PIM) technology was studied using a single-piston capillary rheometer modified by additional backpressure chamber. The influence of pressure and temperature on shear viscosity has been quantified through pressure and temperature sensitivity coefficients derived from Carreau-Yasuda model. The temperature sensitivity of the 50 vol.% compound based on cemented carbide powder is lower than that of pure polymeric binder, and it varies only slightly with pressure. In contrast, the pressure sensitivity of compounds was found to be higher than that of pure polyolefin binder, and it is decreasing function of temperature. In addition, it is shown that temperature sensitivity of binder, which is considerably enhanced by pressure (in contrast to the PIM demands), cannot be determined as being equal to the properties of particular binder components.