3rd International Poultry Meat Congress

P 42 Investigation of Proteolytic and Lipolytic Spoilage Causing Bacteria
for Selling Chicken Meat in Istanbul, Turkey
Aysen Coban 1 , Ali Aydın 1 , Gulay Merve Bayrakal 1 , Ruveyda Gunaydın 1 , Mert Sudagıdan 2
1
İstanbul University, Faculty of Vetyerinary Medicine, Department of Food Hygiene &
Technology, İstanbul, Turkey
2
Konya Food and Agriculture University, Konya, Turkey
Abstract
Chicken meat is among the most popular products all over the world including Turkey.
Moreover, Turkey is the 9 th largest poultry producer country in the world. The aim of the study
was the isolation of bacteria having strong proteolytic and lipolytic activity, causing spoilage
and growing under psychrophilic conditions in chicken meats sold in local bazaar and markets
in Istanbul using conventional methods. The strains were identified at the species level by
molecular techniques (PCR and DNA sequencing) and the prevalence of bacteria causing
spoilage in summer and winter seasons were determined. In this research, a total of 54 samples
(22 samples from winter and 32 samples from summer seasons) of chicken meat were collected.
In the context of isolation with conventional methods, chicken meat samples were incubated with
Standard Method agar and Skim Milk agar for proteolytic bacteria and Lecithin-Lipase agar,
Tributyrin agar and Sierra Medium agar for lipolytic bacteria at +4°C for 7 days. After detection
of proteolytic and lipolytic bacterial colonies, the isolates were analyzed by biochemical tests
such as Gram staining, catalase and oxidase tests. A total of 240 aerobic proteolytic and lipolytic
bacteria were isolated 182 strains in winter season and 58 strains in summer season from
chicken meat samples. Genomic DNA extraction was performed only strong (+++ and ++++)
lipase and protease producing bacteria (total 87; 26 from winter and 61 from summer seasons)
using commercial kit with spin colon technology and 16S rRNA gene region was amplified by
PCR using gene specific primers. The obtained PCR products (approximately 1500 bp) were
sequenced using the same primers. DNA sequencing analysis and comparison with GenBank
revealed that 61/87 of strong proteolytic and lipolytic strains in winter season, were identified as
predominantly Pseudomonas spp. (17 strains Pseudomonas fluorescens, 17 strains P. fragi, and
9 strains Pseudomonas spp.) strains. On the other hand, 26/87 of the strains isolated in summer
season were identified as mostly P.fragi (n:14), P. fluorescens (n:5) and Acinetobacter spp
(n:4). by comparing obtained DNA sequences from GenBank. According to this study, characterization
of spoilage bacteria were determined by molecular biological methods in cold storage (+4 ˚ C) chicken meat
and to extend of the shelf life of these raw chicken meats, it would be appropriate selected specific inactivation
methods for identified spoilage microflora, which was identified PCR based methods, was evaluated.
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