Biofilm-producing abilities of Salmonella strains isolated from Turkey

Abstract

In the present study the biofilm-forming characteristics of 99 serotyped (DMC strains) and 41 genus levelidentified (IS strains) Salmonella strains originating from Turkey were investigated. The strains were selected based on their ability to show the biofilm morphotype on Congo red agar plates. In addition, all strains were evaluated with regard to properties related to forming pellicle structures, physical differences of pellicles, any changes in the media associated with the formation of pellicles, and the presence of cellulose within the formed biofilm matrix as determined using 366 nm UV light. The Salmonella Typhimurium DMC4 strain was the best producer of biofilm grown on polystyrene microtiter plates (optical density at 595 nm: 3.418). In subsequent experiments industrial process conditions were used to investigate different morphotyped Salmonella strains' biofilm-forming capability on stainless steel, a commonly preferred surface for the food industries, and on polystyrene surfaces. The effect of other important industrial conditions, such as temperature (5, 20, 37• C), pH (4.5, 5.5, 6.5, 7.4) and NaCl concentration (0.5, 1.5, 5.5, 10.5%) on the production of biofilm of the different morphotyped Salmonella strains (DMC4; red, dry and rough morphotyped S. Typhimurium, DMC12; brown, dry and rough morphotyped S. Infantis, DMC13; pink, dry and rough morphotyped S. subsp. Roughform) were also assessed. On the other hand, pH values exhibited variable effects on biofilm-forming features for different Salmonella strains on both polystyrene and stainless steel surfaces.

DETERMINATION OF in vitro BIOFILM FORMATION ABILITIES OF FOOD BORNE Salmonella enterica ISOLATES

“…Increase in adherence to a surface at a low temperature may lead to persistence and survival in food-processing environments (Van Houdt and Michiels, 2010). It has been previously demonstrated that lower incubation temperature induced the biofim formation capacities of Salmonella serovars (Stepanović et al 2003, Karaca et al 2013, Milanov et al 2017.…”

Investigation of Biofilm Forming Capacity of Clinical Salmonella Isolatesunder Different Environmental Conditions

“…Yapılan bir çalışmada, gıdaların korunması için geleneksel bir uygulama olan pH ve NaCl seviyelerinin düzenlenmesi ile Salmonella izolatlarında biyofilm oluşumunun önlenebileceği gösterilmiş ve araştırmacılar bu uygulamanın gıda güvenliğine katkı sağlayabileceğini belirtmiş-lerdir (9) . Altmış Salmonella enterica ile farklı çevre koşullarında biyofilm üretiminin test edildiği bir çalışmada pH 5.5 (%58.3), %0.5 NaCl (%48.3) ve 25°C'de (%53.3) yüksek oranda biyofilm oluştuğu gözlenmiştir (3) .…”

“…Biyofilm içerisinde bulunan hücreler, kendi ürettikleri ve dış çevreye karşı kimyasal ve mekanik koruma sağlayan bir matriks içerisine gömülü olarak bulunmakta ve üzerlerinde çok çeşitli bileşiklerin birikmesine neden oldukları için hem endüstriyel alanda hem de tıp alanında büyük sorunların ortaya çıkmasına neden olmaktadırlar (5)(6)(7) . Endüstriyel sanitasyon uygulamalarına rağmen, Salmonella'lar, biyofilm oluşturma yetenekleri sayesinde, polimer, çelik ve cam gibi yüzeylerin yanı sıra organik yüzeylerde de canlılıklarını sürdürebilmektedirler (8,9) . Bu çalışmada, Salmonella izolatlarının antibiyotik duyarlılıklarının, biyofilm oluşturma kapasitelerinin araştırılması ve ayrıca biyofilm oluşumuna çeşitli ortam koşullarının ve siprofloksasin (CIP) varlığının etkisinin incelenmesi amaçlandı.…”

Effects of sub-MIC antibiotic concentrations on biofilm production of Salmonella Infantis

“…on stainless steel, glass and PVC (the most similar to polystyrene material) [27]. They observed that 1.7% of strains growth on stainless steel and glass, but PVC was not colonized at 28 C. In our previous study, we tested biofilm-producing abilities of Salmonella strains at different environmental conditions such as temperature, pH and NaCl concentrations [28]. The highest amount of biofilm was formed by all tested strains on polystyrene at 20 C, and it was produced at similar levels by S. typhimurium (rdar, OD 595 D 3.481) and S. Infantis (bdar, OD 595 D 3.478) strains.…”

“…Cleaned coupons were autoclaved at 121 C for 15 min. Previously proposed biofilm formation model was used to develop biofilm structure on stainless steel coupons and they were individually placed in sterile tubes that contain 3.5 mL of LB wo /NaCl and 1 mL of overnight culture, adjusted to 10 8 CFU/mL, and then incubated at 28 C for 24 h [10]. Following the incubation, coupons were removed with sterile forceps, washed with sterile physiologic sodium chloride solution (to remove loosely attached cells), transferred to a sterile tube and air dried for 10 min.…”