Identification and characterization of endophytic bacteria isolated from in vitro cultures of peach and pear rootstocks

WOS: 000378934900002PubMed ID: 28330195Endophytes are microorganisms which live symbiotically with almost all varieties of plant and in turn helping the plant in a number of ways. Instead of satisfactory surface sterilization approaches, repeatedly occurring bacterial growth on in vitro rootstock cultures of peach and pear was identified and isolated as endophytic bacteria in our present study. Five different isolates from peach rootstocks were molecularly identified by 16S rRNA gene sequencing as Brevundimonas diminuta, Leifsonia shinshuensis, Sphingomonas parapaucimobilis Brevundimonas vesicularis, Agrobacterium tumefaciens while two endophytic isolates of pear were identified as Pseudoxanthomonas mexicana, and Stenotrophomonas rhizophilia. Identified endophytes were also screened for their potential of plant growth promotion according to indoleacetic acid (IAA) production, nitrogen fixation, solubilization of phosphate and production of siderophore. All seven endophytic isolates have shown positive results for IAA, nitrogen fixation and phosphate solubilization tests. However, two out of seven isolates showed positive results for siderophore production. On the basis of these growth promoting competences, isolated endophytes can be presumed to have significant influence on the growth of host plants. Future studies required to determine the antimicrobial susceptibility profile and potential application of these isolates in biological control, microbial biofertilizers and degradative enzyme production

Modification of surface morphology of UHMWPE for biomedical implants

Ion-Beam-Based Nanofabrication; San Francisco, CA; United States; 10 April 2007 through 12 April 2007Ultra High Molecular Weight Polyethylene (UHMWPE) samples were implanted with metal and metal-gas hybrid ions (Ag, Ag+N, C+H, C+H+Ar, Ti+O) by using improved MEVVA Ion implantation technique [1,2]. An extraction voltage of 30 kV and influence of 1017 ions/cm2 were attempted in this experiment, to change their surface morphologies in order to understand the effect of ion implantation on the surface properties of UHMWPEs. Characterizations of the implanted samples with RBS , ATR - FTIR, spectra were compared with the un-implanted ones . Implanted and unimplanted samples were also thermally characterized by TGA and DSC. It was generally observed that C-H bond concentration seemed to be decreasing with ion implantation and the results indicated that the chain structure of UHMWPE were changed and crosslink density and polymer crystallinity were increased compared to unimplanted ones resulting in increased hardness. It was also observed that nano size cracks (approx.10nm) were significantly disappeared after Ag implantation, which also has an improved antibacterial effect. Contact angle measurements showed that wettability of samples increased with ion implantation. Results showed that metal and metal+gas hybrid ion implantation could be an effective way to improve the surface properties of UHMWPE to be used in hip and knee prosthesis.Center for Irradiation of Materials, Alabama A&M Universit

Salamura tipi sofralık siyah zeytinlerdeki küf florasının aflatoksin üreten küfler yönünden incelenmesi ve zeytinlerde aflatoksin aranması için en uygun metodun belirlenmesi

Bu tezin, veri tabanı üzerinden yayınlanma izni bulunmamaktadır. Yayınlanma izni olmayan tezlerin basılı kopyalarına Üniversite kütüphaneniz aracılığıyla (TÜBESS üzerinden) erişebilirsiniz.120 7. SUMMARY In recent years, some studies have shown that sone kinds of molds produce aflatoxin which is harmful for buplic health. Therefore, it has become a necessary work to investigate the aflatoxin producing molds on olive which is a major food in our country. For this reason, we have taken the pickled black olive as the investigation material since it is mainly exposed to molds. These samples have been chosen from the most common types as Gemlik,.Memecik, Gslu and Ayvalık from Aydın, îzmir and Akhisar and their neighborhoods. From 1987, 1288 production years moid flora of 55 different samples of pickled black olive have been examined and af latoxigenic ones have been identifide. At the end, 30 different species of molds were isolated: 12 :.Asp ezrglll usr 15 F118 6.ÖZET Bazı küflerin besinler üzerinde aflatoksin üretmeleri günümüzde halk sağlığa açısından çok büyük bir önem kazanmış.bulunmaktadır. Su nedenler ülkemizde önemli bir besin olan zeytinler üzerinde aflatoksin üreten küflerin incelenmesi gerekli bir konu haline gelmiştir. Yaptığımız çalışmada en çok küflerle karşı karşıya kalmış bulunan salamura tipi siyah zeytinler araştırma materyali olarak seçilmiştir. Salamura siyah zeytin örnekleri en yaygın olarak kullanılan Gemlik,. Memecik, Uslu ve Ayvalık çeşitlerinden; Aydır., İzmir ve Akhisar ve civarlarından toplanmıştır, 1987 ve 1988 yılarına ait 55 siyah salamura zeytin örneğinin küf florası incelenmiş ve bunlar arasından aflatoksigenik olanlar belirlenmiştir. Sonuçta birbirinden farklı 30 küf türü izole edilmiştir. Bunlardan 12'si Altermaria 15'i. Penicilluim 2'si Alternamira ve l'i de Cladosporium'a aittir. Bunların arasında Asperçillus flavus ve Aspergillus paresticus aflatoksigenik türler olup; bu 2 türe ait 13 aflatoksigenik strain izole edilmiştir. Ayrıca incelenen zeytin örneklerindeki ortalama küf sayısı 58 x 10-31 küf kolonisi/gr ve. enfeksiyonlu tane yüzdesi % 41 olarak belirlenmiştir. Zeytinlerden izole edilmiş olan aflatoksigenik strainler inaflatoksin üretme yeteneklerinin belirlenmesinde "APA'% ''CAM'" ve kontrol olarak da pirinç ortamları kullanılmıştır. Ayrıca karşılaştırma yapmak amacıyla aflatoksigenik Aspergillus parasiticus NRRL 2999 ve Aspergillus flavus NRRL.6555 strainleri de aynı şekilde incelenmiştir. Yapılan, incelemeler sonucunda '"APA- ortamında 6 strainin113 0.4 6 ppb/gr ile 34 6 ppb/gr arasında; "CAM"' da 7 strainin 4 ppb/gr iie. 2568 ppb/gr arasında; pirinç üzerinde ise, 7 strainin 106 ppb/gr ile 5900 ppb/gr toplam afiatoksin ürettikleri belirlenmiştir. En yüksek afiatoksin üretimi priniçte;. daha sonra sırayla,?CAMr ve "APA" ortamlarında görülmüştür. Sonuç olarak afatoksigenik küf strainierinin elenmesinde,ucuzluğu, hazırlanma kolaylığı ve çabuk sonuç alınması gibi nedenlerden; "CAM" kullanılması daha uygun bulunmuştur. Çalışmamızda salamura siyah zeytinlerde afiatoksin aranması için uygun bir tayin yöntemi de belirlenmiştir. 3u yöntem, zeytinlerde afiatoksin aranması için Önerilmiş olan çeşitli yöntemlerin modifikasyonuyla geliştirilmiş olup, bu yöntemde ' afiatoksin tayin limiti 5 ppb/gr olarak saptanmıştı

Chitooligosaccharides and their biological activities: A comprehensive review

WOS: 000423720500028PubMed ID: 29352917Chitin is the most abundant natural polysaccharide and chitosan is its most important derivative. Regardless of having various bioactivities, the water insolubilities of chitin and chitosan limit their applications in many industries. The physical, chemical or enzymatic depolymerization of chitin and chitosan deliver chit-ooligosaccharides (COS): water-soluble and low molecular weight derivatives, superior to the parent polymers in multiple aspects. COS exhibit an enormously wide range of biological activities and a remarkable potential to be applied in various industries. This review has fully addressed the latest research on the biological activities of COS and the molecular mechanism behind these activities in a correlation with their physicochemical properties. Furthermore, an attempt has been made to report the commercially available COS products. The bioactivities discussed here may offer new understanding of the applications of COS in numerous sectors

Mutans streptokokların izolasyonunda kullanılan çeşitli seçici besiyerlerinin karşılaştırılması

Dental caries microbiology is related to metabolic activity of mutans streptococci. Studies conducted on several human populations reported that species of mutans streptococci show a wide distribution among humans. Selective media have been used routinely in epidemiological studies on mutans streptococci. The aim of this study was to distinguish the most proper selective media to determine to isolate mutans streptococci serotype c/e/f and d/g that are two main subgroups of the bacteria. Isolation of mutans streptococci in saliva samples from 18 children were detected by using Mitis Salivarius Sucrose Bacitracin Agar (MSBA), Tripticase Yeast Extract-Cystine-Sucrose Agar (TYCA), Tripticase Yeast Extract-Cystine-Sucrose-Bacitracin Agar (TYCSBA) and Tripticase Yeast Extract-Sucrose Agar (TSY20BA). In conclusion, the highest selectivity was determined in MSBA; on the contrary, the other components of the salivary microflora grew in different proportions on TYCA, TYCSBA and TSY20BA.Dental çürüklerin mikrobiyal etiyolojisi öncelikle mutans streptokokların metabolik aktivitesi ile ilişkilidir. Çeşitli insan popülasyonlan ile yapılan çalışmalarda mutans streptokok grubunun dünya üzerinde çok geniş bir dağılım gösterdiği ve çoğu bireylerin bu mikroorganizmaları barındırdığı gözlenmiştir. Mutans streptokoklarla yapılan epidemiyolojik çalışmalarda seçici besiyerleri düzenli olarak kullanılmaktadır. Çalışmada, mutans streptokokların insanlardan yaygın olarak izole edilen iki ana alt grubunun (c/e/f ve d/g) seçici olarak kültürünün yapılabildiği ve koloni morfolojisine dayanan bir tanımlamaya izin veren en uygun seçici besiyerinin belirlenmesi amaçlandı. Bu amaçla 18 çocuktan alınan tükürük örneklerinden mutans streptokokların izolasyonu, Mitis Salivarius Sucrose Bacitracin Agar (MSBA), Tripticase Yeast Extract-Cystine Ağar (TYCA), Tripticase Yeast Extract-Cystine-Sucrose-Bacitracin Agar (TYCSBA) ve Tripticase Yeast Extract-Sucrose Ağar (TSY20BA) seçici besiyerleri kullanılarak incelendi. Sonuç olarak, MS B A'ı n seçici özelliğinin çok yüksek olduğu; buna karşılık TYCA, TYCSBA ve TSY20BA'da tükürük mikroflorasının diğer üyelerinin de değişen oranlarda büyüyebildiği saptanmıştır

The enhancement of polygalacturonase and polymethylgalacturonase production on solid-state conditions by Aspergillus foetidus

WOS: 000258403400001In this study, a previously isolated strain of Aspergillus foetidus Ege-K-635 producing highly active polygalacturonase and polymethylgalacturonase was used for improvement of enzyme production using solid-state conditions. To enhance the enzyme yield, the mixture of two substrates such as sugar beet pulp and wheat bran, having different ratios of carbon-nitrogen and moisture levels was used. Further the effect of the amount of inoculum was investigated. Physical parameters for the highest polygalacturonase and polymethylgalacturonase production under solid state conditions were determined on wheat bran: the sugar beet pulp (1:2) mixture substrate composition having a 31:1 carbon-nitrogen ratio with 8 x 10(6) spores/gram of dry substrate as the inoculum amount. Adequate moisture levels were 75% and 70% for polygalacturonase and polymethylgalacturonase, respectively. Under these conditions, the highest activities obtained were 385 +/- 12.3 Ug(-1) on the third day for polygalacturonase and 18.3 +/- 3.2 Ug(-1) on the second day for polymethylgalacturonase.Scientific Research Commission at Celal Bayar UniversityCelal Bayar UniversityThe authors gratefully thank to the Scientific Research Commission at Celal Bayar University for providing support to carry out a part of the present work and to Dr. Ergun Taskin for obtaining and handling the beet pulp

Production of galactooligosaccharides by beta-galactosidase from Thermus oshimai DSM 12092

WOS: 00020980560035