Development of antigen-capture ELISA using monoclonal antibodies for the detection of brucellae in milk

In this study, a Brucella antigen-capture ELISA (Ag-cELISA) prototype was developed. To study the validity of the developed Ag-cELISA, milk samples collected from Brucella-positive goats (n=120) and cattle (n= 64), as well as from unknown Brucella-status cattle (n=105) and sheep (n=65) herds were tested by Ag-cELISA, I-ELISA, and culture method. All Brucella-positive samples were confirmed using PCR. It was found that the developed Ag-cELISA could detect 50-100 bacteria per well (equivalent to 103 to 2×103 cells per mL) as the lowest limit of detection (LOD) and was therefore considered moderately sensitive to detect brucellae in milk. In an infected goat herd, out of 120 milk samples, 41, 32, and 17 were positive by Ag-cELISA, I-ELISA, and culture, respectively. Ag-cELISA detected 15 positive cases out of 17 culture-positive milk samples. Two culture-positive milk samples were not detected in Ag-cELISA. The relative sensitivity and specificity between Ag-cELISA and I-ELISA were 78% and 100%, respectively. In an infected cow herd, out of 64 milk samples, 32, 23, and 11 were found positive by Ag-cELISA, I-ELISA, and culture, respectively. Ten out of 11 culturally positive milk samples were found positive by Ag-cELISA. The relative sensitivity and specificity between the Ag-cELISA and I-ELISA were 71.9% and 100%, respectively. From randomly collected 105 cow and 110 sheep milk samples from herds of unknown Brucella-infection status, three (2.85%) and five (4.5%) samples were found positive using Ag-cELISA, respectively. These results showed that Ag-cELISA could be used to detect brucellae in milk more practically and safely than bacterial culture. On the other hand, this information re-affirms that milk can be an important source of brucellosis and creates a public health risk in humans; therefore, increased public awareness is of utmost importanc

Antimicrobial effect of various plant extracts on raw meatballs

Çiğ köfte günlük olarak hazırlanıp, birkaç saat içerisinde tüketilmesi gereken, raf ömrü kısa ve mikrobiyal açıdan riskli bir gıdadır. Bu araştırmada; çiğ köfte numunelerine belirli oranlarda değişik baharat ekstrakları ilave edilmesinin, çiğ köftelerin raf ömrü üzerine etkisi etkileri incelenmiştir. Çalışmada kullanılacak çiğ köfte hazırlandıktan sonra, %0,5 ve %1 oranında bitki ekstraktları (yeşil çay, hibiskus, tarhun, ceviz kabuğu, limon kabuğu yağı, portakal kabuğu yağı) ilave edilerek +4oC de 21 gün süreyle depolanmıştır. Depolamanın 0, 7, 14 ve 21. günlerinde, Lactobacillus spp., Lactococcus spp., maya ve küf, Pseudomonas spp., Escherichia coli, , Staphylococcus aureus, toplam koliform, Listeria spp., Salmonella spp., toplam aerobik mezofilik ve toplam aerobik psikrofilik mikroorganizma varlığı araştırılmış; ayrıca depolama süresince, baharatların çiğ köftenin rengine etkisi de incelenmiştir. Depolama süresi boyunca numunelerin sırasıyla parlaklık-koyuluk, kırmızı-yeşil ve sarı-mavi renk göstergesi olan; L*, a* ve b değerlerinde artış gözlenmiştir. Yapılan mikrobiyolojik analiz sonuçlarına göre ise numunelerin hepsinde maya-küf sayısı, Pseudomonas cinsi bakteri sayısı, laktik asit bakteri sayısı ve Lactococcus cinsi bakteri sayılarında azalma görülürken; toplam aerobik mezofilik bakteri sayısında kullanılan ekstrakta göre farklılık gözlemlenmiş, patojen mikroorganizma ve Staphylococcus aureus cinsi bakterilerin üreme göstermediği tespit edilmiştir.Raw meatballs is a food which should be prepared daily and consumed within a few hours, shelf life is short and microbial in terms of risk. This research was carried out with the aim of determining the effect of various spices and modification of raw meatballs on shelf life. The effects of the spice extracts on the shelf life were investigated by adding the spice extracts to the prepared raw meat ball samples at certain ratios. After preparing the raw meatballs to be used in the study, plant extracts (green tea, hibiscus, tarragon, walnut shell, lemon peel oil, orange peel oil) were added at the rates of 0,5% and 1% and stored at + 4 ° C for 21 days. On days 0, 7, 14 and 21 of storage; total aerobic mesophilic bacteria, yeast and mold, total coliform bacteria, Lactobacillus spp., Lactococcus spp., Pseudomonas spp., Listeria spp., Salmonella spp. Escherichia coli and Staphylococcus aureus counts has been researched. In addition, the effect of the spice on the color of raw meatballs during storage was also examined. During the storage period; the samples were of brightness-darkness, red-green and yellow-blue color indicator, respectively; L *, a * and b * values were increased. According to the microbiological analysis results; yeast-mold count, Pseudomonas spp., lactic acid bacteria and Lactococcus bacteria counts decreased in all samples. In contrast, the total aerobic mesophilic bacterial counts differed according to the extract used. In addition, Listeria spp, Salmonella spp, Escherischia coli and Staphylococcus aureus were found not to reproduce

Molecular characterization of pseudomonas aeruginosa isolated from clinical bovine mastitis cases

This study aimed to investigate the presence and distribution of virulence determinants and their antimicrobial susceptibilities of 44 Pseudomonas aeruginosa isolates obtained from clinical bovine mastitis cases. In addition, selected 6 P. aeruginosa isolates were further characterized using whole-genome sequencing (WGS). Based on the presence of T3SS-related genes, 25% of the isolates were found to carry exoU and/or exoS genes belonging to invasive (exoU-/exoS+, 18.2%) and cytotoxic (exoU+/exoS-, 6.8%) strains. But, none of the isolates carried both exoU and exoS genes. In terms of other virulence genes examined, various virulence gene profiles were observed among the isolates. The majority of the isolates (72.7%) were susceptible to all tested antimicrobials. Resistance rates to ciprofloxacin and carbapenems (imipenem and meropenem) were determined as 25% and 4.5%, respectively. WGS analysis indicated the presence of different resistome, but fosA genes in all isolates, and different combinations of mutations in gyrA, parC, oprD, efflux pump, and genes playing a role in the regulation of ampC gene expression. Different sequence types (STs) and serotypes were found in representative isolates with the occurrence of the O11-ST235 clone, which is a worldwide multidrug-resistant high-risk clone representing a serious public health threat. The findings of this study provide valuable information on P. aeruginosa isolated from clinical bovine mastitis cases and current antimicrobial resistance levels and virulence determinants

Molecular characterization of trichophyton verrucosum strains isolated from cattle by PCR-RFLP

Dermatofitler, insan ve hayvanlarda keratin içeren dokuları infekte ederek dermatofit infeksiyonuna neden olmaktadırlar. Trichophyton verrucosum sığır dermatofitozis olgularının en yaygın etkenidir. Trichophytosis, bütün dünyada hayvancılık sektöründe önemli ekonomik kayıplara neden olması yanında zoonoz olmasıyla da insan sağlığını tehdit etmektedir. Sığırlardan genellikle T. verrucosum izole edilmektedir. Sığırlar bu etkenin doğal rezervuarıdırlar. Bu çalışmanın amacı, sığırlarda hastalığa neden olan dermatofitlerinin izolasyonu ve izole edilen T. verrucosum suşlarının Internal Transcribed Spacer (ITS) bölgelerinin PCR-RFLP ile moleküler ayrımının yapılmasıdır. Bu amaçla dermatofitozisli sığırlardan 90 adet örnek alınarak kültürleri yapıldı. Bu örneklerin kültürü sonucunda 35 (%38,8) adet T. verrucosum izole ve identifiye edildi. Bu suşların DNA izolasyonu gerçekleştirilerek ITS bölgelerin amplifikasyonu gerçekleştirildi. T. verrucosum suşlarının MvaI ve HinfI enzimleri kullanılarak yapılan Restriction Fragment Lenght Polymorphism (RFLP) analizleri sonucunda bir adet RFLP profiline rastlandı. Sonuç olarak, izole edilen T. verrucosum suşlarının PCR-RFLP sonucunda tek bir profile sahip olduğu, farklı profil örneklerinin saptanması için farklı bölgelerden hatta farklı ülkelerden suşların PCR-RFLP’lerinin yapılması gerektiği kanısına varıldı.Dermatophytes infect tissues containing keratin in humans and animals, causing dermatophytosis infection. Trichophyton verrucosum is the most common agent of bovine dermatophytosis cases. Trichophytosis causes big economic lossess throughout the world and also threatens human health by being a zoonosis. T. verrucosum is usually isolated from cattle. Cattle are the natural reservoirs of this agent. The aim of this study is to isolate disease-causing dermatophytes in cattle and to carry out molecular separation of Internal Transcribed Spacer (ITS) regions of the isolated T. verrucosum strains by PCR- Restriction Fragment Lenght Polymorphism (PCR-RFLP). For this purpose, 90 samples were taken from the cattle with dermatophytosis for cultural examination. As a result of the culture of these samples, 35 (38.8%) T. verrucosum were isolated and identified. DNA isolation of these strains was made and amplification of ITS regions was performed. It was only one RFLP profile was found according to the results of RFLP analysis of T. verrucosum strains using MvaI and HinfI enzymes. At the end of study, it was founded that the isolated T. verrucosum strains showed a single profile by PCR-RFLP analysis and PCR-RFLP was a useful tool for the molecular characterization of the strains. İt was also concluded that PCR-RFLPs of strains from different regions or even from different countries might be necessary in order to detect different profiles of the tested samples

Investigation of the effect of spray and freeze drying methods in the production of encapsulated colorant matter from red cabbage (Brassica oleracea L.)

Bu çalışmada kırmızılahanadan (Brassica oleracea L.) elde edilen renk maddesinin enkapsülasyon yöntemi ile stabilitesinin arttırılması ve uygulanan farklı kurutma yöntemlerinin toz renk maddesinin antioksidan kapasitesi ve antosiyanin içeriği üzerine etkisi incelenmiştir. Elde edilen toz üründe püskürtmeli kurutucu ve enkapsülasyon uygulaması ile verim %2,51'den %9,20'ye, dondurarak kurutma da ise 24,20'den 34'e çıkarılmıştır. Toz üründe yapılan fiziksel analizlerden akabilirlik ve yapışabilirlik değerleri sırasıyla %17 ve 1,21 olarak hesaplanmıştır. Yapılan enkapsülasyon işleminden sonra L*, a* ve C* değerlerinde artış gözlenmiştir. Antioksidan aktivite değerini ölçmede kullanılan IC50 değeri zamanla toz ürünlerde artış göstermiştir. IC50 değeri enkapsüle edilmiş püskürtme kurutulmuş örneklerde %25 artış gösterirken dondurularak kurutulan örneklerde %34,91 artış gözlenmiştir. Kurutma yönteminin enkapsüle edilen toz örneklerde toplam monomerik antosiyanin içeriği üzerine etkisi incelendiğinde dondurularak kurutulan örneklerde %11,60 azalma gözlenirken, püskürtme yöntemi ile kurutulan örneklerde %29,93 azalma gözlenmiştir.In this study, the stability of colorant obtained from red cabbage (Brassica oleracea L.) by encapsulation method and the effect of different drying methods on the antioxidant capacity and anthocyanin content of powder colorant were investigated. Powder product obtained by spray dryer and encapsulation application yield from 2.51% to 9.20%, freeze drying was also increased from 24.20% to 34%. Flowability and stickability values were calculated as 17% and 1.21% from physical analysis of powder product, respectively. After the encapsulation process, L *, a * and C * values increased. The IC50 value used to measure the antioxidant activity value increased over time in powder products. The IC50 value increased by 25% in encapsulated spray-dried samples, while the freeze-dried samples increased by 34.91%. When the effect of drying method on total monomeric anthocyanin content of encapsulated powder samples was examined, a decrease of 11.60% was observed in freeze-dried samples, 29.93% reduction was observed in spray dried samples

Magnetic features and compensation behaviors of a mixed spin (1/2,1) Ising ferrimagnetic system on a hexagonal lattice

We studied dynamic magnetic properties and compensation behaviors of a mixed spin (1/2, 1) Ising ferrimagnetic system on a hexagonal lattice within the path probability method that contains more than one rate constants and the average dynamic order parameters were coupled. We found the phases in the system by solving the average dynamic magnetizations. We examined the thermal features of dynamic magnetizations to characterize the nature of the dynamic phase transitions (DPTs) and obtained the DPT temperatures. We constructed the dynamics phase diagrams in six different planes, which contain the dynamic tricritical, critical end, double critical end, zero-temperature critical and multicritical special points as well as the paramagnetic (P), non-magnetic (NM), ferromagnetic (I) fundamental phases and P + I, NM + I mixed or hybrid phases depending on system parameters. We also investigated the dynamic compensation behaviors, and the N-, P-, Q-, R- and the S-types compensation behaviors were found. (C) 2021 Elsevier B.V. All rights reserved