Kontaminacija biljaka patogenim bakterijama iz vode za navodnjavanje

Consumption of fresh vegetables and fruits is a healthy diet supply and it is recommended as prevention of illnesses. There is an increasing trend in consumption of fresh vegetables and fruits in the world, and their microbiological quality is very important for public human health and protection. Contamination of vegetables and fruits is the result of presence of human pathogen bacteria which can contaminate products in any part of production chain. There is an evidence of presence of: Salmonella spp., Escherichia coli, E. coli O157:H7, L. monocytogenes on the fresh vegetables. Salmonellosis is connected with tomato, sprouts, cantaloupe etc. E. coli and E. coli O157:H infections are linked with lettuce, sprouts, carrot etc. There has been an increasing number of outbreaks caused by human pathogen on fresh vegetables and fruits in the recent years. Contaminated irrigation water is a very effective vector of the transmission of human pathogen to plants, so microbiological safe water has special importance in health safety food production. Contamination of fresh vegetables by human pathogen bacteria depends on bacterial ability to colonize plant. In the case of microbiological contamination of fresh vegetables and fruits, it is very difficult to carry out decontamination of product, because it is impossible to remove all attached bacteria only by washing. The goal of this research is an investigation of presence and identification of pathogen bacteria in the irrigation water and on vegetables, transmission of pathogen bacteria from irrigation water to plants and studying/monitoring the ability of the human pathogen to colonize the surface and endophyte of root, stem and leaf of different vegetable species. Microbiological quality of water and vegetables is estimated on the basis of the presence and number of coliform bacteria, as well as certain species of pathogen bacteria. Isolated strains of human pathogen bacteria are identified by their morphological, ecological and biochemical properties. Transmission of pathogen bacteria from irrigation water to plants, as well as colonization of plants by human pathogen bacteria was investigated by: applying PCR method, using green fluorescent protein transformed bacteria, fluorescence in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM)...Konzumiranje svežeg povrća i voća je satavni deo zdrave ishrane i preporučuje se kao prevencija nastanka raznih obolenja. U svetu postoji trend povećanja konzumiranja svežeg povrća i voća, pa je njegov mikrobiološki kvalitet od izuzetne vaznosti za javno zdravlje i bezbednost. Kontaminacija povrća i voća je rezultat prisustva patogenih bakterija, koje mogu kontaminirati proizvode u bilo kom delu proizvodnog lanca. Na svežem povrću je moguće prisustvo: Salmonella spp., Escherichia coli, E. coli O157:H7, L. monocytogenes. Salmoneloze se povezuju sa paradajizom, klicama raznih biljaka, dinjom. Infekcije izazvane E. coli i E. coli O157:H7 su povezane sa zelenom salatom, klicama raznih biljaka, mrkvom i dr. Poslednjih godina je u porastu broj epidemija izazvanih patogenima na svežem povrću i voću. Kontaminirana voda za navodnjavanje je efikasan vektor prenosa patogena na biljke, pa mikrobiološki ispravna voda ima poseban značaj u proizvodnji zdrastveno bezbedne hrane. Kontamincija svežeg povrća patogenim bakterijama zavisi od sposobnosti ovih bakterija da kolonizuju biljku. U slučaju pojave mikrobiološke kontaminacije svežeg povrća i voća, teško je izvršiti dekontaminaciju proizvoda, jer je bakterije nemoguće potpuno ukloniti samo pranjem vodom. Cilj ovog rada je ispitivanje prisustva i identifikacija patogenih bakterija u vodi za navodnjavanje i na povrću, proučavanje prenosa patogenih bakterija iz vode za navodnjavanje do biljke i praćenje sposobosti patogenih bakterija da površinski i endofitno kolonizuju koren, stablo i list različitih vrsta povrća. Mikrobiološki kvalitet vode i povrća je procenjivan na osnovu prisustva i broja koliformnih bakterija, kao i brojnosti određenih vrsta patogenih bakterija. Izolovani sojevi patogenih bakterija su identifikovani na osnovu njihovih morfoloških, ekoloških i biohemijskih osobina. Prenos patogenih bakterija iz vode za navodnjavanje do biljke, kao i kolonizacija biljaka patogenim bakterijama je proučavana primenom PCR metode, green fluorescent protein genetske transformacije bakterija, metodom fluorescence in situ hybridization (FISH) i laser skening konfokalnom mikroskopijom (CLSM)..