The addition of sachets or pads containing volatile antimicrobial agents into packages has been the most successful commercial application of antimicrobials to packaging. In this study, the effect of oregano (Origanum onites) essential oil on the extension of shelf life of overwrap packed fresh chicken drumsticks was investigated. Meat exudate absorbent pads were sprayed with 5 mL of oregano essential oil at a concentration of 1.5% in distillate water. Sampling was carried out at 0, 3, 5, and 7 d of the refrigerated storage. Total viable count, psychrotrophs, pseudomonads, members of the family Enterobacteriaceae, yeasts, and lactic acid bacteria were enumerated. Physicochemical analysis and sensorial evaluation were also conducted. The shelf life of fresh chicken drumsticks was approximately 3 d. Oregano essential oil extended product shelf life by approximately 2 d. Thus, incorporation of essential oils to absorbent pads may have supplementary applications in food packaging.

The aim of this study was determine carriage rate and methicillin resistance of Staphylococcus aureus among food handlers. Samples were collected by swabbing the mouth, nasal cavity and hands of food workers. The isolation of S. aureus was performed using a culture method and verified by using a genetic method (PCR). The presence of mecA gene was analysed by PCR. The fourteen antimicrobial disks were also used to determine antimicrobial susceptibility of S. aureus. The 56 out of 282 isolates were identified as S. aureus. It is found that 10 workers out of 28 carried S. aureus in their nasal cavity while 4 and 3 workers out of 21 carriered S. aureus in mouth and hands respectively. None of the isolates carried mecA genes and also their antibacterial susceptibility test for methicillin resistance, using cefoxitin (30 µg), shown that all the isolates was susceptible to methicillin. In conclusion, the results of the present study indicated that the prevalence of antibiotic resistance of S. aureus strains isolated from food handlers was low. However carriage rate of S. aureus among food handlers was quite high.

We investigated the presence of enterotoxigenic and methicillin-resistant Staphylococcus aureus (MRSA) in a kitchen of a catering firm by collecting 100 food samples and 100 utensil-equipment samples after sanitation. Additional 186 samples in total were collected by swabbing the mouths, noses and hands of 62 kitchen staff members during working hours. The isolation of S. aureus was performed using a culture method and verified by using a genetic method (PCR). The presence of toxin genes and the toxic shock syndrome gene (tst) was analyzed by PCR. ELISA was used to investigate whether the isolates bearing a toxin gene that produces enterotoxin or not. In this research we obtained 1930 isolates from 386 samples. Using molecular typing by PCR, 842 Staphylococcus spp. were found of which 307 (36.4 %) were identified as S. aureus. 198 (64.4 %) of the S. aureus strains were identified as CoA positive and 89 (28.9 %) as MRSA. Our data demonstrate the presence of MRSA and enterotoxigenic S. aureus in a catering kitchen providing daycare and hospital refectories. Given the facts that the rate of kitchen staff members contaminated with enterotoxigenic strains was rather high and that the kitchen contained S. aureus even after sanitation and that there was uneducated staff and insufficient hygiene practices aroused suspicions of the presence of biofilms and/or multi-resistant strains which could manifest a serious public health concern.

IntroductionAflatoxins are secondary metabolites produced by molds that have carcinogenic, mutagenic, and teratogenic effects on humans and animals (1-3). Among the aflatoxins, aflatoxin B 1 (AFB 1 ) is one of the strongest known hepatocarcinogens and is classified as a category 1A carcinogen by the International Agency for Research on Cancer (4). Due to their importance in showing these effects in the consumption of contaminated foods, there is a serious effort made by the food industry to make products safe. Moreover, considering the tendency of consumers to prefer natural products because of the worry about possibly hazardous food additives, both researchers and producers are taking responsibility to investigate new ways as an answer to the consumer expectations.Although the different methods used at present are to some extent successful, they have major disadvantages with limited efficacy, possible losses of important nutrients, and normally high costs. Many workers in the field are of the opinion that the best solution for decontamination should be detoxification by biodegradation, giving a possibility for removal of mycotoxins under mild conditions without using harmful chemicals and without significant losses in nutritive value and palatability of decontaminated food and feed (5). A number of studies have found that some microorganisms, especially lactic acid bacteria, break down or bind to aflatoxins. Researchers have obtained different results in these studies conducted to investigate the in vitro aflatoxin binding/degradation effect of lactic acid bacteria (6-9). Zinedine et al. (10) indicated that the toxin binding level changes in some environmental conditions having different pH and temperature. Supporting this finding, Haskard et al. ( 7) also found that environmental conditions, acid and heating applications, and the structure of the bacteria had an important effect on the stability of the toxin-bacteria complex. In another study, Kabak (11) showed that the aflatoxin B 1 binding capability of probiotic lactic acid bacteria varied in vitro, and in food had 32%-46.5% of the in vitro toxin binding rate. Fuchs et al. (12) found that the effectiveness of lactic acid bacteria in detoxifying ochratoxin and patulin was affected by toxin concentration, cell density, pH of the environment, and whether the cells were viable. Based on these and similar results, Hernandez-Mendoza et al. (13) suggested that lactic acid bacteria bound the toxins to different extents depending on the environment and the amount of bile salt present.Another challenge for researchers is achieving the same good results when lactic acid bacteria are applied to food. First of all, certain temperatures and pH levels must be provided; otherwise, the microorganisms would not show their effects. Probably, a higher number of bacteria would

Bu çalýşmada, Kars İli piyasasýnda perakende satýşa sunulan ballar, Türk Standartlarý (TS 3036) ve Türk Gýda Kodeksi Bal Tebliğine uygunluk bakýmýndan incelenmiştir. Yürütülen analizler sonucunda test edilen 20 örnekten 10'unun ticari glukoz içermesinden, 13'ünün diyastaz sayýsý ve 1'inin de sahip olduğu Hidroksimetil Furfurol değerinden dolayý uygun özellik taşýmadýklarý kanaatine varýlmýştýr. Bunun yanýnda, örneklerden 19'unun pH değeri, 4'ünün invert şeker ve 4'ünün de sakkaroz miktarýnýn standart ölçütlerinde bildirilen limitlerin dýşýnda olduğu belirlenmiştir. Ayrýca 3 örnekte stafilokok sayýsý 1x10 2 kob/g'dan daha yüksek saptanmýştýr. Sonuç olarak analize alýnan ballarýn hiçbirinin test edilen parametreler yönünden, kýstas alýnan standartlara uygun olmadýğý görüldü.

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SummaryThe aim of this study was to isolate bacteriocin-producing lactic acid bacteria (LAB) from foods. A total of 12700 LAB were isolated from foods and screened for their bacteriocin production. Among them, 601 isolate showed a clear antimicrobial activity against indicator strains. After neutralization 35 of the cultures retained active. The antimicrobial activities of strains were lost after treatment with proteases. The antimicrobial metabolites were heat stable and were active pH range of 2-12. The bacteriocin which produced by Lactococcus lactis ssp. lactis isolated from kashar samples was partially purified by ammonium sulphate precipitation, dialysis, following ion-exchange chromatography. It was also found that this bacteriocin was cationic. The apparent molecular mass of partially purified bacteriocin, as indicated by activity detection after Tricine-SDS-PAGE, was 2.4 kDa, 4 kDa or 15 kDa. In this study antimicrobial substance of LAB from food showed strong antibacterial activity against Gram-negative and Gram-positive indicator microorganisms. Those were also found that these bacteriocins were stable at temperatures used in food manufacturing and storage. Bacteriosinogenic LAB or bacteriocins might be useful as a natural preservative for inhibiting food-borne pathogens in particular Listeria monocytogenes in foods.Keywords: Animals food, Lactic acid bacteria, Bacteriocin, Antimicrobial activity Gıdalardan İzole Edilen Laktik Asit Bakterilerinin Bakteriyosin Üretme Yeteneklerinin Araştırılması ÖzetBu çalýşmada, gýdalardan bakteriyosinojenik laktik asit bakterilerinin (LAB) izolasyonu amaçlanmýştýr. Gýdalardan izole edilen toplam 12700 LAB'nin antimikrobiyel etkisi test edilmiştir. Bu izolatlardan sadece 601 adedi çalýşmada kullanýlan indikatör suşlara karşý antimikrobiyel etki göstermiştir. LAB'nin ürettiği laktik asitin ve hidrojen peroksitin güçlü antimikrobiyel etkisi göz önüne alýndýğýnda bu etkinin ortadan kaldýrýlmasý için katalaz ilavesiyle birlikte ortam nötrlendiğinde antimikrobiyel etkisini sürdüren sadece 35 izolat olduğu belirlenmiştir. İzolatlarýn etkisi proteolitik enzimlerin varlýğýnda kaybolmuştur. Üretilen antimikrobiyel etkili metabolitlerin gýda üretim ve muhafaza sýcaklýklarýnda ve geniş pH (pH 2-12) aralýğýnda aktivitelerini sürdürdükleri gözlenmiştir. Kaşar peynirinden izole edilen Lactococcus lactis ssp. lactis suşunun ürettiği bakteriyosin kýsmi olarak saflaştýrýlarak tanýmlanmaya çalýşýlmýştýr. İzole edilen bakteriyosinojenik suşlarýn Gram-negatif ve Gram-pozitif indikator mikroorganizmalara karşý oldukça güçlü antimikrobiyel etkiye sahip olduğu belirlenmiştir. Bakteriyosinojenik LAB ve/veya onlarýn bakteriyosinleri gýda kaynaklý patojenlerden özellikle Listeria monocytogenes'in inhibisyonu için doğal bir katký maddesi olarak kullanýlabilir.

The use of antibiotics in food animals creates an important source of antimicrobial resistant bacteria that can spread to humans through the food chain. Strains of Salmonella spp. with resistance to antimicrobial drugs are now widespread in all countries. The present study analysed the prevalence and antimicrobial resistance of Salmonella spp. isolates in raw chicken wings. Out of 200 fresh raw chicken wing packages 102 (51%) samples were positive. Antibiotic resistance test was performed on 200 isolates out of 336 after being confirmed. All the isolates showed multiple resistance against the antibiotics investigated with the average 0.371 multiple antibiotic resistance (MAR) index. None of the isolates were resistant to amoxicillin/clavulanate and cefoxitin. Only 2 isolates showed intermediate resistance to imipenem. The major resistance was observed against nalidixic acid (95%), trimethoprim/sulfomethoxazole (92%), tetracycline (92%), streptomycin (90%) and trimethoprim (81%). Even though only 4 isolates were resistant against ciprofloxacin, high percentage of intermediate resistance (92%) was detected. Some of the isolates were also resistant to gentamicin (7%), cefoperazone (2%), ampicillin (24%), chloramphenicol (24%), cephazolin (7%) and cefotaxime (39%). According to our results high prevalence and the increase in antibiotic resistant Salmonella spp. is of concern and constitutes a threat to public health. Keywords: Salmonella, Chicken, Antibiotic resistance Piliç Kanatlarından İzole Edilen Salmonella spp.'nin Antibiyotik Direnci ÖzGıda amaçlı hayvan yetiştiriciliğinde antibiyotik kullanımı, gıda zinciri yoluyla insana geçiş yapan, antibiyotiklere dirençli bakterilerin en önemli kaynağı konumundadır. Günümüzde antimikrobiyal ilaçlara dirençli Salmonella spp. tüm ülkelere yayılmış durumdadır. Bu çalışma ile kanatlı etlerindeki Salmonella prevalansı ve izolatların antimikrobiyal direnç durumları araştırılmıştır. İncelenen 200 piliç kanat paketinden 102 tanesi (%51) pozitif olarak değerlendirilmiş ve konfirme edilen 336 izolattan 200'ünün antibiyotik duyarlılık durumları belirlenmiştir. Buna göre tüm izolatların ortalama 0.371 çoklu antibiyotik direnci (MAR) indeksi ile çoklu antibiyotik direncine sahip olduğu görülmüştür. İzolatların hiçbiri amoxicillin/clavulanate ve cefoxitin'e direnç göstermemiştir. Yalnızca 2 izolatın imipenem'e dirençli olduğu saptanmıştır. Asıl direncin nalidixic acid (%95), trimethoprim/sulfomethoxazole (%92), tetracycline (%92), streptomycin (%90) ve trimethoprim (%81) antibiyotiklerine karşı şekillendiği gözlenmiştir. Her ne kadar sadece 4 izolat ciprofloxacin'e karşı tam dirençli olsa da orta düzeydeki direnç oranının yüksek olduğu (%92) ortaya konmuştur. İzolatlar ayrıca gentamisin (%7), cefoperazone (%2), ampicillin (%24), chloramphenicol (%24), cephazolin (%7) ve cefotaxime (%39)'e karşı direnç geliştirmiştir. Çalışmamızın bulguları Salmonella spp. 'nin yüksek prevalansı ve antibiyotik direncindeki artış nedeniyle halk sağlığına yönelik önemli bir tehdit oluşturduğuna d...