تشخیص و تعیین فراوانی لیستریا مونوسیتوژنز در نمونه های مواد غذایی با بررسی مولکولی ژن hlya

ﻣﻘﺪﻣﻪ: ﻟﯿﺴﺘﺮﯾﻮﻟﯿﺰﯾﻦ isteriolysin o o llo ﯾﮏ ﻫﻤﻮﻟﯿﺰﯾﻦ ﻓﻌﺎل ﺷﺪه ﺑﺎ ﺳﻮﻟﻔﯿﺪرﯾﻞ ﻣﺘﺼﻞ ﺑﻪ ﮐﻠﺴﺘﺮول اﺳﺖ ﮐﻪ ﺗﻮﺳﻂ ژن hlya ﻟﯿﺴﺘﺮﯾﺎ ﻣﻮﻧﻮﺳﯿﺘﻮژﻧﺰ ﮐﺪﮔﺬاری ﻣﯽ ﺷﻮد ﻫﺪف از اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﺗﺸﺨﯿﺺ و ﺗﻌﯿﯿﻦ ﻓﺮاواﻧﯽ ﻟﯿﺴﺘﺮﯾﺎ ﻣﻮﻧﻮﺳﯿﺘﻮژﻧﺰ در ﻧﻤﻮﻧﻪ ﻫﺎی ﻣﻮاد ﻏﺬاﯾﯽ ﺑﺎ ﺑﺮرﺳﯽ ﻣﻮﻟﮑﻮﻟﯽ ژن hlya اﺳﺖ. ﻣﻮاد و روش ﻫﺎ: ﻣﻄﺎﻟﻌﻪ ﺣﺎﺿﺮ ﯾﮏ ﻣﻄﺎﻟﻌﻪ ﻣﻘﻄﻌﯽ- ﺗﻮﺻﯿﻔﯽ اﺳﺖ. ﻧﻤﻮﻧﻪ ﮔﯿﺮی از اواﺳﻂ ﻣﻬﺮ ﻣﺎه 1398ﺗﺎ ﭘﺎﯾﺎن دی ﻣﺎه ﻫﻤﺎن ﺳﺎل ﺑﻪ ﻃﻮل اﻧﺠﺎﻣﯿﺪ. ﺻﺪو ﺷﺼﺪ و ﭘﻨﺞ ﻧﻤﻮﻧﻪ اﻧﻮاع ﻣﺨﺘﻠﻒ ﮔﻮﺷﺖ، ﺳﺒﺰﯾﺠﺎت، ﻫﻤﺒﺮﮔﺮ و ﻣﯿﮕﻮ ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺖ. ﺟﻤﻊ آوری ﻧﻤﻮﻧﻪ ﻫﺎ ﺑﻪ ﺻﻮرت ﺗﺼﺎدﻓﯽ از رﺳﺘﻮران ﻫﺎ، اﻏﺬﯾﻪ ﻓﺮوﺷﯽ ﻫﺎ، ﻣﮑﺎن ﻫﺎی ﺗﻬﯿﻪ ﻏﺬای آﻣﺎده و ﺳﻮﭘﺮ ﻣﺎرﮐﺖ ﻫﺎی ﻣﺨﺘﻠﻒ اﻧﺠﺎم ﺷﺪ. ﮐﻠﯿﻪ ﻧﻤﻮﻧﻪ ﻫﺎی ﺟﻤﻊ آوری ﺷﺪه، ﺑﺎ آزﻣﺎﯾﺸﺎت ﻓﻨﻮﺗﯿﭙﯿﮑﯽ و ﺑﯿﻮﺷﯿﻤﯿﺎﯾﯽ ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺖ و ﻧﻤﻮﻧﻪ ﻫﺎی ﻣﺸﮑﻮک ﺑﻪ ﻟﯿﺴﺘﺮﯾﺎ ﻣﻮﻧﻮﺳﯿﺘﻮژﻧﺰ ﭘﺲ از اﺳﺘﺨﺮاج dna ﺑﺎ روش ﺟﻮﺷﺎﻧﺪن ﺑﺎ ﭘﺮاﯾﻤﺮﻫﺎی اﺣﺘﺼﺎﺻﯽ ﺑﺮای ژن hlya ارزﯾﺎﺑﯽ ﺷﺪ. ﯾﺎﻓﺘﻪ ﻫﺎ: ﺑﺮرﺳﯽ ﻫﺎی ﻓﻨﻮﺗﯿﭙﯿﮏ ﮐﺸﺖ ﻣﯿﮑﺮوﺑﯽ و ﺑﺮرﺳﯽ ﺑﯿﻮﺷﯿﻤﯿﺎﯾﯽ 18 ﻧﻤﻮﻧﻪ آﻟﻮده ﺑﻪ ﻟﯿﺴﺘﺮﯾﺎ ﻣﻮﻧﻮﺳﯿﺘﻮژﻧﺰ را ﺗﺎﯾﯿﺪ ﮐﺮد، از اﯾﻦ ﺗﻌﺪاد ﺑﻄﺮﯾﻖ pcr ژن hlya 6/06 10% ﻧﻤﻮﻧﻪ ﻟﯿﺴﺘﺮﯾﺎﻣﻮﻧﻮﺳﯿﺘﻮز ﻣﺜﺒﺖ ﺑﻮد. ﺷﯿﻮع آﻟﻮدﮔﯽ در ﮐﺒﺎب ﮐﻮﺑﯿﺪه 9/37 %، اﻧﻮاع ﮔﻮﺷﺖ ﻣﺮغ 4/44 %، ﻫﻤﺒﺮﮔﺮ ﻣﺤﻠﯽ 16/66 % و ﮐﺎﻫﻮ 13/33 % ﺑﻮد. اﯾﻦ ﯾﺎﻓﺘﻪ ﻫﺎ در ﻣﻘﺎﯾﺴﻪ ﺑﺎ دﯾﮕﺮ ﻣﻄﺎﻟﻌﺎت در ﺑﺮﺧﯽ ﻣﻮاد ﻏﺬاﯾﯽ ﻫﻤﺒﺮﮔﺮ ﻣﺤﻠﯽ ﺷﯿﻮع ﺑﯿﺸﺘﺮی داﺷﺖ و در ﺑﻌﻀﯽ ﻣﻮاد ﻏﺬاﯾﯽ ﮔﻮﺷﺖ ﻣﺮغ ﮐﻤﺘﺮ ﺑﻮد. ﻧﺘﯿﺠﻪ ﮔﯿﺮی: اﺳﺘﻔﺎده از روش ﺑﯿﻮﺷﯿﻤﯿﺎﯾﯽ در ﺗﻌﯿﯿﻦ ﻓﺮاواﻧﯽ ﻟﯿﺴﺘﺮﯾﺎ ﻣﻮﻧﻮﺳﯿﺘﻮژﻧﺰ در ﻧﻤﻮﻧﻪ ﻫﺎی ﻣﻮاد ﻏﺬاﯾﯽ در ﺷﻬﺮﺳﺘﺎن ﺳﻨﻨﺪج از درﺻﺪ ﺑﺎﻻی ﻣﺜﺒﺖ ﮐﺎذب ﺑﺮﺧﻮردار ﺑﻮد.

detection and determination of the frequency of listeria monocytogenes in food samples by molecular analysis of the hlya gene

introduction: listeriolysin llo is a sulfhydryl-activated hemolysin bound to cholesterol, that is encoded by the hlya gene of listeria monocytogenes. the aim of this study was to detect and determine the frequency of listeria monocytogenes in food samples through molecular analysis of the hlya gene.materials and methods: the present study was a descriptive cross-sectional assay conducted from the middle of october 2018 to the end of january of the same year. one hundred sixty-five samples of different types of meat, vegetables, hamburgers and shrimps were examined. samples were randomly collected from restaurants, delicatessens, prepared food places, and different supermarkets. all samples were analyzed with phenotypic and biochemical tests. the samples suspected of listeria monocytogenes, after dna extraction, were evaluated by pcr with specific primers for the hlya gene. then the data and results were evaluated with using spss v.23 software and excel software.results: phenotypic methods microbial culture and biochemical investigation confirmed 18 positive samples for listeria monocytogenes, of which 10 6.06% samples were positive for listeria monocytogenes by pcr of the hlya gene. the rate of contamination in pounded kebab was 37.9%, chicken meat 4.4%, local hamburger 16.66% and lettuce 13.33%. compared to other studies, these findings were more prevalent in some foods e.g., local hamburger and less in others e.g., chicken meat .conclusion: the use of biochemical methods for determining the frequency of listeria monocytogenes in food samples in sanandaj had a high percentage of false positives.