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Klebsiella species are becoming a major global public health concern. In particular, the increase in multidrug‐resistant strains is a cause for concern. This study was aimed at determining the antibiotic susceptibility of two different isolates of Klebsiella quasipneumoniae subsp. similipneumoniae and determining the virulence characteristics and bacterial morphology under subminimum inhibitory concentrations (sub‐MICs) of antibiotics. In this study, two multidrug‐resistant K. quasipneumoniae subsp. similipneumoniae isolates were identified, one of which was clinical, and the other was isolated from freshwater. The MICs of the antibiotics meropenem, chloramphenicol, ciprofloxacin, and kanamycin were determined for these isolates. The effects of the sub‐MICs on the virulence and morphological characteristics of the bacteria were investigated in comparison with K. pneumoniae (ATCC 13883). The MICs of meropenem, chloramphenicol, ciprofloxacin, and kanamycin were 0.04, 20, 2, and 8 μg/mL in the clinical isolate; 0.2, 15, 5, and 2 μg/mL in the freshwater isolate; and 0.03, 3, 0.1, and 0.3 μg/mL for K. pneumoniae. The biofilm‐forming ability of K. quasipneumoniae subsp. similipneumoniae isolates decreased with antibiotic sub‐MICs. Siderophore activity increased only with MIC/4 of kanamycin and MIC/2 of chloramphenicol in the clinical isolate (p > 0.05). Furthermore, bacterial morphology and expression of virulence genes were affected differently by the sub‐MICs. This study showed that biofilm formation decreased and that the changes in bacterial morphology and expression of virulence genes were very different in the presence of 1/2 and 1/4 sub‐MIC antibiotics. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kombucha is a Far East-originated fermented beverage that is valued by people for its health benefits worldwide. Fruit and fruit juice of the gilaburu plant is used in traditional medicine. In this study, fruit juice of gilaburu is used in a 21-day kombucha fermentation. Sensory properties, microbiological profile, total phenolic and flavonoid content, and antioxidant and antibacterial activity of the prepared beverages for days 0, 7, 14, and 21st were investigated. In addition, chemical compound profiles were determined using LC-MS/MS on the 7th and 14th days. When evaluated in general, gilaburu-flavoured kombucha yielded better results than traditional kombucha in terms of microbiological analysis, antibacterial activity, total phenolic content, and sensory properties. In addition, the LC-MS/MS analysis of the beverages revealed fourteen active compounds. Notably, on the 7th day, gilaburu-flavoured kombucha exhibited elevated levels of fumaric acid, quinic acid, chlorogenic acid, catechin, 4-OH-benzoic acid, epicatechin, vitexin and hesperidin compared to traditional kombucha. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Institute of Science & Technology / Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi is the property of Igdir University, Institute of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bordetella pertussis is the causative agent of a respiratory infection called pertussis (whooping cough) that can be fatal in newborns and infants. The pathogen produces a variety of antigenic compounds which alone or simultaneously can damage various host cells. Despite the availability of pertussis vaccines and high vaccination coverage around the world, a resurgence of the disease has been observed in many countries. Reasons for the increase in pertussis cases may include increased awareness, improved diagnostic techniques, low vaccine efficacy, especially acellular vaccines, and waning immunity. Many efforts have been made to develop more effective strategies to fight against B. pertussis and one of the strategies is the use of outer membrane vesicles (OMVs) in vaccine formulations. OMVs are attracting great interest as vaccine platforms since they can carry immunogenic structures such as toxins and LPS. Many studies have been carried out with OMVs from different B. pertussis strains and they revealed promising results in the animal challenge and human preclinical model. However, the composition of OMVs differs in terms of isolation and purification methods, strains, culture, and stress conditions. Although the vesicles from B. pertussis represent an attractive pertussis vaccine candidate, further studies are needed to advance clinical research for next-generation pertussis vaccines. This review summarizes general information about pertussis, the history of vaccines against the disease, and the immune response to these vaccines, with a focus on OMVs. We discuss progress in developing an OMV-based pertussis vaccine platform and highlight successful applications as well as potential challenges and gaps. [ABSTRACT FROM AUTHOR]

For recent years fermented milk products, especially kefir, are highly preferred food product due to their positive and therapeutic effects on health. Microbial composition of the kefir grains directly related with the region they are obtained and affect properties of kefir straightforwardly in traditional fermentation method. Therefore, bioactivity investigation of kefir grains used in fermentation process has great importance. In this study, comparative bioactivity analysis of cow milk and goat milk kefirs fermented with one local grain obtained from Antalya, Turkey and one commercial grain are demonstrated. For this purpose, microbiological analysis, antibacterial and antioxidant activity analysis, total phenolic and total flavonoid compound measurements of kefir samples were done. Our results concluded that, antibacterial and antioxidant activity of kefirs fermented with local grain are almost similar to those fermented with commercial grain and local grain kefirs can be a valuable and safe alternative for consumers due to its phenolic compound and flavonoid content. [ABSTRACT FROM AUTHOR]