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The prevalence and antimicrobial susceptibilities of Staphylococci and Streptococci were assessed from subclinical mastitis cases. One hundred Coagulase-Negative Staphylococci (CNS) and 34 Streptococci were identified. The most frequently isolated species were Staphylococcus haemolyticus (27%) and Staphylococcus simulans (24%). Susceptible CNS species revealed the highest resistance to penicillin G (58%), ampicillin (48%), neomycin (20%), and oleandomycin (14%). CNS methicillin resistance rates within 82 isolates were 21.95% and 1.22% by disk diffusion and PCR methods, respectively. These results suggested the disk diffusion method was more prone to yield false positives. Partial sequencing of the 16S rRNA region from the mecA carrying isolate (S. haemolyticus) was homologous with S. haemolyticus sequences/accessions obtained from GenBank. However, the mecA gene sequence from this isolate was more closely allied with the S. aureus mecA gene of human origins. Identical sequence data was acquired from the National Center for Biotechnology Information (NCBI) database, suggesting horizontal gene transfer between the two species. CNS beta-lactamase activity within 81 isolates was 29.63%. The most frequently isolated Streptococcus species were S. uberis (52%) and S. agalactiae (15%). Oleandomycin was the least effective antimicrobial agent on these isolates with 59% susceptibility. Results indicated that CNS and Streptococci exhibited various antimicrobial resistance responses. Consequently, isolation and identification of udder pathogens in herds suffering from subclinical agents is essential to select the most effective antimicrobial agent. Moreover, multiple resistance features of methicillin resistant (MR) isolates should be considered during antimicrobial susceptibility tests.

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Peach (Prunus persica [L.] Batsch) is a perishable product and its storage period may be extended by using different postharvest methods. For this purpose, peaches harvested at the commercial ripening stage were treated with individual and combined effects of putrescine (1 mM) and ultrasonic treatment (32 kHz for 10 min); postharvest storage quality of peach fruit was evaluated during storage at 0-1 °C for 28 d. Quality characteristics such as weight loss, fruit firmness, respiration rate, total sugar, total soluble solid content, titratable acidity, chilling injury, and decay rate were determined at the beginning and during the storage period at 1-wk intervals. The result showed that individual and combined effects of putrescine and ultrasonic treatment, when compared to control fruits, could increase peach fruit postharvest life by inducing resistance to different diseases and chilling injury with no noticeable effect on fruit quality attributes such as weight loss, total soluble solids, and total sugar. At the same time, a combined putrescine and ultrasound treatment was found to be more effective than other treatments in decreasing respiration rate and maintaining firmness and acidity. Peach storability could be extended with a combined putrescine and ultrasound treatment because it delays the ripening processes.

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The objective of this work was to determine the effects of UV-C and chitosan coatings, alone or in conjunction, on the quality of strawberry fruit during storage. The treated fruits were examined for weight loss, respiration rate, soluble solids content, titratable acidity, ascorbic acid contents, total anthocyanins, total phenolic contents, decay incidence and sensory analysis of strawberry fruit were investigated during cold storage 1±0.5°C and 90±5% RH for 15 days. The result showed that chitosan coating with UV-C irradiation could further reduce decay incidence of strawberry fruit, restrain increase of respiration rate and weight loss of strawberry fruit compared to other treatments. Moreover, the total anthocyanins and total phenolic contents were maintained at higher level, and the decrease of ascorbic acid was restricted during storage period. Likewise, sensory analysis results also showed the effectiveness of UV-C + chitosan treatment by retaining the quality of strawberry fruit. Control and individual UV-C treatment had similar effects on respiration rate and weight loss. The results showed that UV-C + chitosan treatment can be an effective method for enhancing the phytochemical content and delaying fruit senescence of strawberry fruit during cold storage.

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Araştırmada, J.H.Hale çeşidi şeftali meyvelerinde potasyum permanganat ve modifiye atmosfer paket (MAP) uygulamasının muhafaza süresi ve kalite üzerine etkileri araştırılmıştır. Birinci grup meyvelere sadece MAP uygulaması yapılırken, ikinci grup meyvelere MAP+potasyum permanganat (KMnO 4) saşe uygulaması yapılmıştır. Meyveler 0-1°C sıcaklık ve %90±5 oransal nem koşullarında 30 gün süreyle depolanmıştır. Soğukta muhafaza periyodunda 10 günde bir alınan meyve örneklerinde, meyve eti sertliği, suda çözünebilir kuru madde miktarı, titre edilebilir asit miktarı, toplam fenolik madde miktarı, toplam flavonoid miktarı, yünlüleşme ve paketler içerisindeki %O 2 ve %CO 2 miktarları belirlenmiştir. Araştırma sonucunda, KMnO 4 uygulamasının modifiye atmosfer paketleme ile birlikte kullanıldığında özellikle meyve eti sertliğinin korunmasında ve solunumun yavaşlatılmasında etkili olduğu belirlenmiştir. 30 günlük muhafaza sonunda meyve eti sertliği MAP uygulanmış meyvelerde ortalama 3.9 kg, MAP+KMnO 4 uygulanmış meyvelere ise ortalama 5.6 kg olarak bulunmuştur. Başlangıç değeri 282.3 mg GAE kg-1 olan fenolik madde ve 232.2 mg kg-1 olan flavonoid içeriklerindeki değişimler, muhafaza sürecinde KMnO 4 uygulanmış meyvelerde kontrol grubu meyvelere göre daha yavaş gerçekleşmiştir. KMnO 4 uygulamasının yünlüleşmenin engellenmesi üzerine önemli bir etkisinin olmadığı görülmüştür.