Zeki Gürler

The microbiological quality of ready-to-eat salads in Turkey: a focus on Salmonella spp. and Listeria monocytogenes.

The microbiological safety of ready-to-eat (RTE) foods is of special concern as they are not exposed to further processing before consumption. In the present study, Listeria monocytogenes and Salmonella spp. were isolated from 15(6%) and 21(8%) samples respectively out of 261 RTE foods commercialized in Turkey. Escherichia coli was present in 10(4%) samples analyzed. Psychrotrophic aerobic populations >6logCFU/g were found in 36 (14%) of the samples, while total coliforms were detected in 155 (59%) of samples analyzed. All of the Salmonella spp. and L. monocytogenes isolates tested, exhibited resistance to one or more antimicrobial agents used. For Salmonella spp. isolates, resistance to penicillin (69%), erythromycin (38%), gentamicin (36%), tetracycline (36%) neomycin (33%), ampicillin (33%), amikacin (33%), vancomycin (33%), streptomycin (29%) cefotaxime (9%) and oxacillin (9%) was observed. For L. monocytogenes isolates, resistance to erythromycin (23%) and cephalothin (20%) was evident. The presence of pathogens and the relatively high resistance among the bacteria tested in RTE foods could pose public health and therapeutic problems in consumers. These results indicate the need of implementing hygienic rules in the production chain of RTE foods to ensure microbiological safety and to improve shelf life.

The ameliorative effects of boron against acrylamide-induced oxidative stress, inflammatory response, and metabolic changes in rats

Acrylamide (ACR) is a hazardous substance associated with the accumulation of excessive reactive oxygen species and causes oxidative stress. Presence of ACR in foods leads to public health concerns due to its known neurotoxic, genotoxic, and carcinogenic effects. The present study investigated the ameliorative effects of boron (B) against ACR exposed rats. Forty Wistar albino male rats, fed with low-boron diet, were randomly and equally allocated into 5 groups. The control group was orally treated with physiological saline as placebo, the second group was orally given 15 mg/kg ACR. The other groups were orally treated with 15 mg/kg ACR and B at the levels of 5, 10, and 20 mg/kg/day for 60 days, respectively. ACR-treatment significantly increased malondialdehyde levels whereas decreased glutathione levels in rat tissues. Also, ACR-treatment increased the activities of superoxide dismutase and catalase in erythrocytes and tissues. Meanwhile, mRNA expression levels of NFĸB, IFN-γ, IL-1β, and TNF-α in liver and brain of rats were increased under ACR treatment. Additionally, ACR caused a significant decrease in the level of high-density lipoprotein, with increase in the levels of low-density lipoprotein, triglyceride, cholesterol, glucose, urea nitrogen, and creatinine. Lastly, B alleviated histopathological alterations induced by ACR in rat tissues.

Effects of Yucca Schidigera To Diet of Dairy Cows on Blood Oxidant-Antioxidant Balance, Biochemical Parameters, and Milk Quality

Hayvan beslemede verim artirici ve buyumeyi tesvik edici olarak kullanilan ionofor grubu antibiyotikler basta olmak uzere bircok kimyasal katki maddesi Avrupa’da yasaklanmistir. Son yillarda bu maddelerin yerine bitkilerden elde edilen saponinler gibi biyolojik aktif urunler kullanilmaktadir. Bu arastirmanin amaci steroidal saponin iceren Yucca schidigera (YS) bitki tozunun sutcu sigirlarda kan oksidan-antioksidan denge ve sutte malondialdehit, ure-N ile sut kalitesi uzerine etkilerini belirlemektir. Calismada ortalama sut verimi 20,7 kg ± 3,1 kg/gun ve canli agirliklari 552 kg ± 30 kg olan 10 adet Holstayn inek kullanildi. Calismanin baslangicinda ve 15 gunun sonunda (15 gun boyunca rasyonlarina 1500 pp Yucca schidigera ilave edildi) bu hayvanlardan sabah yemlemesinden oncesi ve 2 saat sonrasinda kan ve sut ornekleri alindi. Kanda malondialdehit (MDA), antioksidan aktivite (AOA), redukte glutatyon (GSH), superoksid dismutaz (SOD), katalaz (CAT), A vitamini, beta karoten, amonyak tayini ve sut orneklerinde MDA, ure-N ile sut kalite parametreleri olculdu. Istatistik analizler icin SPSS paket programi, verilerin degerlendirilmesinde paired-t testi uygulandi. Yemleme oncesi ve sonrasinda kanda MDA ve amonyak duzeyleri dusuk bulundu (p < 0,05), yemleme oncesi GSH yemleme sonrasi GSH ve β-karoten duzeyleri ise yuksek bulundu (p < 0,05). Calismada yeme YS ilavesinin sut MDA ve ure azotu duzeylerini dusurdugu (p ˂ 0.05), sut yag yuzdesini artirdigi (p ˂ 0.05), diger parametrelere ise etkisinin olmadigi bulundu. Bu bulgular YS ilavesinin sutte MDA ve ure azotu duzeylerini dusurdugunu gosteren ilk calismadir. Sonuc olarak, bu calismada elde edilen bulgular, sut ineklerinin rasyonlarina dogal bir antioksidan olarak YS ilavesinin kanda antioksidan savunmayi guclendirebilecegi ve sut kalitesinin artmasinda olumlu bir etkisinin olabilecegini gostermektedir.

Antibiotic Resistance Profile of Lactic Acid Bacteria Origine From Animal Foods

Gunumuzde laktik asit bakterileri ile ilgili teknolojik calismalar artmaya baslamistir. Bu durum bu mikroorganizmalarin starter kultur ozelliklerinin arastirilmasina olanaklar saglamaktadir. Bir yandan da hayvanlarda cesitli amaclarla bilincsizce kullanilan antibiyotikler bu mikroorganizmalarda antibiyotik direnc olusumuna neden olmaktadir. Patojen mikroorganizmalarin coklu antibiyotik direncliligi konusu ile ilgili calismalar yayginlassa da halk sagligini tehdit etmedigini dusundugumuz mikroorganizmalarin antibiyotik direnc gelistirmesi konusu da onem tasimaktadir. Bu derlemede laktik asit bakterilerinin antibiyotik direncliligi ile ilgili bilgilendirme yapilmasi amaclanmistir.