Air quality and impact on food safety

© Published under licence by IOP Publishing Ltd. Air is an important potential source of contamination in different areas of human endeavor (medicine, pharmaceuticals, agriculture, food industry etc.). During the various technological procedures of producing and processing food, its contamination by polluting substances contained in air, such as suspended particles (physical contamination), combustion products and volatile organic substances (chemical contamination) and biological pollutants (bacteria, viruses, molds and mites) very often occurs. Although the sources of air contamination are numerous (poor construction aspects of the building, improper air conditioning and ventilation, etc.), basic and common sources are people and their activities in food production plants. The task of responsible food production is to adequately and continuously implement good production practices, and thereby, prevent potentially harmful practices, to ensure environmental health and safety for the life and work of the staff in that environment, and to create conditions for safe food production, while protecting the environment

Praćenje promene broja bakterija familije enterobacteriaceae u pastrmci i odrescima šarana upakovanim u vakuum i modifikovanu atmosferu

Kvar ribe može se definisati kao bilo koja promena u mesu ribe koja proizvod čini neprihvatljivim za ljudsku ishranu i najčešće nastaje kao rezultat rasta mikroorganizama. Od toga koji su mikroorganizmi najzastupljeniji u ribi u trenutku ulova u velikoj meri zavisi i kolika će biti njena održivost tokom skladištenja. Bakterije koje pripadaju familiji Enterobacteriaceae su fakultativni anaerobi, gram negativni i katalaza pozitivni mikroorganizmi. Ovoj familiji pripadaju sledeći rodovi: Salmonelle, Escherichia, Proteus, Shigella, Serratia, Citrobacter, Klebsiella, Enterobacter i Erwinia, a neki od njih su izraziti patogeni i izazivači velikog broja različitih oboljenja kod ljudi, kao što su septikemija, pneumonija, meningitis, infekcije urinarnog trakta, bolesti organa za varenje i mnogih drugih bolesti. Široko su rasprostranjeni u spoljašnjoj sredini, a neki su saprofitski stanovnici digestivnog trakta. Cilj ovog eksperimenta je bio da se ispita rast bakterija familije Enterobacteriaceae u svežoj pastrmci i odrescima šarana upakovanim u vakuum i modifikovanu atmosferu. Uzorci su podeljeni u tri grupe. Grupa I je upakovana u modifikovanu atmosferu sa odnosom gasova 60%CO2 i 40%N2, grupa II je upakovana u modifikovanu atmosferu sa 40%CO2 i 60%N2 dok je III grupa upakovana u vakuum. Odnos gas/uzorak u pakovanju bio je 2:1. Svi uzorci su skladišteni pri istovetnim uslovima na temperaturi od +3˚C. Određivanje broja bakterija familije Enterobacteriaceae prema ISO 21528 -2:2004 obavljeno je 0, 7. i 14. dana skladištenja. U pastrmci i odrescima šarana upakovanim u modifikovanu atmosferu sa 60%CO2 i 40% N2 (I grupa), rast ukupnog broja enterobakterija bio je sporiji nego u pastrmci i odrescima šarana upakovanim u modifikovanu atmosferu sa 40%CO2 i 60%N2 (II grupa) ili pak u vakuum (III grupa). Ovo se može objasniti antimikrobnim dejstvom ugljen-dioksida, koji je procentualno najzastupljeniji u smeši gasova u koju su upakovani uzorci I grupe kao i činjenicom da ugljen-dioksid deluje inhibitorno pre svega na gram-negativne bakterije, kakvi i jesu mikroorganizmi iz familije Enterobacteriaceae. Najveću stopu rasta imale su enterobakterije u pastrmci i odrescima šarana III grupe tj. u uzorcima upakovanim u vakuum. Ovi rezultati ukazuju na sposobnost Enterobacteriaceae da rastu u anaerobnim uslovima, na temperaturi frižidera u proizvodima upakovanim u vakuum. Modifikovana atmosfera smanjuje ukupan broj enterobakterija, a najniža vrednost je dobijena kod odrezaka šarana upakovanih u modifikovanu atmosferu sa 60%CO2 i 40%N2

Deoxycholic Acid as a Modifier of the Permeation of Gliclazide through the Blood Brain Barrier of a Rat

Major problem for diabetic patients represents damage of blood vessels and the oxidative stress of the brain cells due to increased concentration of free radicals and poor nutrition of brain cells. Gliclazide has antioxidative properties and poor blood brain barrier (BBB) penetration. Bile acids are known for their hypoglycemic effect and as promoters of drug penetration across biological membranes. Accordingly, the aim of this study is to investigate whether the bile acid (deoxycholic acid) can change the permeation of gliclazide, through the blood brain barrier of a rat model type-1 diabetes. Twenty-four male Wistar rats were randomly allocated to four groups, of which, two were given alloxan intraperitoneally (100 mg/kg) to induce diabetes. One diabetic group and one healthy group were given a bolus gliclazide intra-arterially (20 mg/kg), while the other two groups apart from gliclazide got deoxycholic acid (4 mg/kg) subcutaneously. Blood samples were collected 30, 60, 150, and 240 seconds after dose, brain tissues were immediately excised and blood glucose and gliclazide concentrations were measured. Penetration of gliclazide in groups without deoxycholic acid pretreatment was increased in diabetic animals compared to healthy animals. Also in both, the healthy and diabetic animals, deoxycholic acid increased the permeation of gliclazide through that in BBB

Stanje ekosistema za uzgoj pastrmke sa aspekta mikrobiološkog rizika

Control of microbiological status of ponds and a fish itself is of great importance while the aim of control is to detect indicators of faecal pollution and to evaluate the potential risk of consumption of contaminated aquacultural products. In this paper we investigated microbiological population of rainbow trout ponds, in trout itself and in sludge. Investigations were performed at the beginning of autumn, end of autumn and at the beginning of winter. Results indicated that microbiological status of the pond ecosystem was mainly satisfactory, although there were some sporadic cases of A.hydrophila on trout skin at the beginning of autumn