Effectiveness research on a wavy lamellar plate-type biofilter with a capillary system for the humidification of the packing material applying introinduced microorganisms

To conduct research, a new generation plate-type air treatment biofilter for removing gaseous pollutants from air has been applied under laboratory conditions. A distinguishing feature of the packing material of the biofilter includes wavy lamellar polymer plates placed to each other and producing a capillary effect of humidification. While having such an arrangement, wavy lamellar plates also have rather wide spacing (6 mm), and therefore the employment of the structure of the plate-type packing material decreases the aerodynamic resistance of the device. A wavy porous plate is made of a polymer plate that ensures stiffness. Both sides of the wavy lamellar polymer plate have attached steam exploded birch fiber pellets under which, to increase plate capillarity, not-woven caulking material is put. This technological decision allows effectively enhancing the durability of the biopacking material. The work presents the results of research on the efficiency of the biodestruction process of acetone, xylene and ammonia. With reference to the conducted investigation, the high efficiency of air treatment and microbiological activity has been established. When pollutant gases (acetone, xylene and ammonia), under a velocity of 0.08 m s–1, passed through the biopacking material, microbiological activity in the material reached on average 1×108 cfu/cm2, and air treatment efficiency made 90.7%

Micromycetes, producers of toxins, detected on stored vegetables

In 2003-2004, investigations of mycological contamination of stored and newly harvested vegetables were carried out. The aim of the study was to detect fungal species able to synthesize toxic metabolites, which are spread on vegetables under various conditions. For mycological investigations, samples of carrots, onions and cabbage were taken from storehouses with different storage periods and conditions. Penicillium expansum, P. nalgiovense, Mucor silvaticus and Penicillium verrucosum were more frequently detected on carrots, Penicillium expansum - on onions and Aspergillus niger, Botrytis cinerea, Mucor hiemalis, Penicillium funiculosum and Penicillium expansum - on cabbages. Storing conditions of vegetables influenced distribution of different fungal species. Primary screening using CYA and YES test-media showed that 46.7 % of tested strains may be evaluated as toxin producers. The ability of fungi to produce mycotoxins depends on their growth substrata. According to Rf and fluorescence in the UV of compounds comparing with standards, such toxins as patulin, cytochalasin and penitrem were identified. The ability of Penicillium expansum Sv-168-1 growing on different foodstuff and especially potato to produce patulin was confirmed quantitativelyVytauto Didžiojo universitetasŽemės ūkio akademij

Changes in antagonistic activity of lactic acid bacteria induced by their response to technological factors

This study examined the changes in antagonistic activity of selected lactic acid bacteria (LAB) in response to technological factors used in food production. The antimicrobial activity of 12 selected LAB strains was assessed against the bacterial and fungal strains using the agar well diffusion method. Sodium chloride (NaCl) 6.5–8.0%, glucose 20-30% and pH 4.0, pH 8.0 and higher were the most crucial factors in reducing the spectra of the microorganisms antagonized. Heating at 80 °C or 100 °C had a greater negative impact than 63 °C on the antifungal activity of LAB. Freezing at –72 °C eliminated the antifungal activity, or it changed from fungicidal to fungistatic. Although each LAB demonstrated the ability to retain antimicrobial activity induced by various technological factors, Lactococcus lactis 768/5 was superior in retaining high antimicrobial activity against tested indicator strains

Sveikatos rizikos veiksnių, susijusių su Aspergillus amstelodami ir jo produkuojamų mikotoksinų poveikiu, tyrimas

The data have revealed that OTA acts as a genotoxic agent in the Jurkat, blood-derived cell line, and evokes retardation of cell proliferation in the hepatic cell line MH-22A. The data of the present investigation showed that the test strain A. amstelodami 724 isolated from wheat grains stored in bins might be evaluated as a toxin producer. Health risks associated with A. amstelodami and its mycotoxins were proved using laboratory mice in vivo and cells in the culture in vitro

Micromycetes Affecting Nuts, Maize and Barley Used for Food and Animal Feed

Santr. anglBibliogr.: p. 170 ( 7 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij

Effect of copper, zinc and lead acetates on microorganisms in soil

Santr. angl., lietBibliogr.: p. 68-69 (35 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij