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The increasing consumer demand for less processed and more natural food products – while improving those products’ quality, safety, and shelf-life – has raised the necessity of chemical preservative replacement. Biopreservation refers to extended storage life and enhanced safety of foods using the natural microflora and (or) their antibacterial products. Chitinolytic enzymes are of biotechnological interest, since their substrate, chitin, is a major structural component of the cell wall of fungi, which are the main cause of the spoilage of food and raw plant material. Among the several organisms, many bacteria produce chitinolytic enzymes, however, this behaviour is not general. The chitinase activity of the lactic acid bacteria is scarcely known and studied.The aim of the present study was to select Lactobacillus strains that have genes encoding chitinase, furthermore, to detect expressed enzymes and to characterise their chitinase activity. Taking into consideration the importance of chitin-bindig proteins (CBPs) in the chitinase activity, CBPs were also examined. Five Lactobacillus strains out of 43 strains from 12 different species were selected by their chitinase coding gene. The presence of the chitinase and chitin-biding protein production were confirmed, however, no chitinolytic activity has been identified.

Nagy-Gasztonyi M., Nagy A., Németh-Szerdahelyi E., Pauk J., Gelencsér É. (2010): The activities of amylases and α-amylase inhibitor in wide-range herbicide resistant wheat lines. Czech J. Food Sci., 28: 217-224. The activities of total amylase, α-amylase, and α-amylase inhibitor in the albumin-globulin fractions of isogenic non transgenic control (CY 45) and ppt (phosphinothrichin) resistant transgenic spring wheat (triticum aestivum L.) lines (T106, T116, T117, T124, T128, T129) were studied in two subsequent years. The plants were either sprayed with a selective herbicide Granstar (G), a wide range herbicide Finale 14 SL (F), or were grown without spraying (Q). Samples were obtained from field trial experiments of the Cereal Research Non Profit Co (Szeged, Hungary). Our results showed an increased trend in total amylase activity of untreated transgenic wheat lines in comparison with non transgenic wheat. The herbicide treatments enhanced the total amylase activity in both transgenic and non transgenic wheat samples. The changes in α-amylase inhibitor activity showed the same trend as that observed in total amylase activity in transgenic lines.