Design And Manufacture Of Polymeric Nanofiber Membranes Via Electrospinning Method

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2009Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2009Bu çalışmada endüstriyel ölçekte, elektrospinning yöntemiyle nanolif membran üretebilecek pilot bir sistemin tasarım ve imalatı gerçekleştirilmiştir. Çalışmanın ilk aşamasında, elektrospinning işleminin temelleri ve elektrospinning işlemini etkileyen parametreler literatürdeki bilgiler ve deneysel çalışmalarla desteklenerek laboratuar ölçeğinde irdelenmiştir. Sonraki aşamada elektrospinning ile nanolif üreten birimlerin sayısı arttırılarak ve her bir birimin üretim kapasitesi iyileştirilerek elektrospinning işlemini etkileyen parametrelerin değişimi gözlenmiştir. Geliştirilen elektrospinning pilot makinesi için üretim birimi olarak iğne sistemi seçilmiştir. Sırasıyla bir, iki, dört, dokuz, on altı, yirmi dört ve yüz iğneli elektrospinning düzenekleri ile başarılı bir şekilde nanolif üretimi gerçekleştirilmiştir. Pilot elektrospinning makinesinde farklı sayıda iğne sistemleri denenmiştir. Optimizasyon çalışmalarının sonucunda 256 iğneden oluşan, bir metre eninde efektif nanolif membran üreten pilot makine başarıyla çalıştırılmıştır. Ayrıca çalışmada, termoplastik poliüretan nanoliflerden oluşan su geçirmez nefes alabilir membranın ve poliakrilonitril nanoliflerden oluşan batarya separatör membranın tasarımı, üretimi başarıyla gerçekleştirilmiştir. Nanolif membranların karakterizasyonları ticari muadilleriyle karşılaştırılarak yapılmıştır.In this study, design and production of a pilot system, which can produce nanofiber membrane via electrospinning method at industrial scale, was carried out. At the first stage of the study, Fundamentals of electrospinning process and parameters affecting the electrospinning process were examined by supporting electrospinning literature and experimental works at laboratory scale. At the following stage, variations of parameters affecting the electrospinning process were observed with increasing number of units and improving the production rate of each unit that produce electrospun nanofiber. Needle system was chosen as a production unit for developed electrospinning pilot machine. Nanofiber production was successfully realized by electrospinning setups that respectively have one, two, four, nine, sixteen, twenty four and one hundred needles. In the pilot electrospinning machine, various numbers of needles were examined. As a result of optimization works, 256 needled pilot machine, which produce one meter width effective nanofiber membrane, was successfully run. Additionally, design and production of a waterproof breathable membran consists of thermoplastic polyurethane nanofibers and a battery separator membrane consists of polyacrylonitrile nanofibers were successfully carried out. Characterization of nanofiber membranes were made by comparing them with commercially available of their equivalents.Yüksek LisansM.Sc

Inhibitory Effect Of Propolis (Bee Gum) Against Staphylococcus Aureus Bacteria Isolated From Instant Soups

In this study, microbiological quality of instant soups sold in markets and the antibiotic susceptibility of Staphylococcus aureus isolated from instant soups were examined. Total aerobic mesophilic bacteria and S. aureus counts of 6 different types of instant soups were analyzed. Microbiological analysis was carried out in a total of 72 packages of soups, including three replicates. Total aerobic mesophilic bacteria counts and S. aureus counts were determined to be 3.51–4.53 log cfu/g and 0.93–1.71 log cfu/g, respectively. Coliform bacteria were not detected in any of the tomato soups analyzed. The highest number of coliform bacteria (2.10 log cfu/g) was detected in Ezogelin soups. Escherichia coli was not detected in any of the samples analyzed. In addition, the inhibitory effects of five different antibiotics and three different propolis extracts supplied from three different regions of Turkey (Corlu, Kirklareli and Ordu) were examined against S. aureus isolated from the instant soups. Using S. aureus bacteria isolated from tripe soup, a zone diameter of 36.62±0.17 mm was observed with Cefixime. The smallest zone diameter was obtained with Streptomycin (14.74±0.4mm). Zone diameters with propolis samples from Ordu, Corlu and Kirklareli were 10.18±0.04 mm, 7.07±0.45 mm and 6.21±0.14mm, respectively. All of the S. aureus bacteria isolated were sensitive to the Amoxicillin. Propolis extracts were inhibitory towards S. aureus isolated from instant soups, but propolis samples obtained from different geographical regions showed varying antimicrobial effects.Bu çalışmada, marketlerden alınan hazır çorbaların mikrobiyolojik kalitesi ve hazır çorbalardan izole edilen Staphylococcus aureus’un antibiyotiğe duyarlılığı incelenmiştir. Hazır çorbaların 6 çeşidinde 72 pakette 3 tekrar olmak üzere toplam mezofil bakteri ve Staphylococcus aureus sayısı belirlenmiştir. Toplam mezofil bakteri sayısı ve S.aureus sayısı sırasıyla 3,51–4,53 log kob/g and 0,93–1,71 kob/g bulunmuştur. Domates çorbasında koliform bakteri bulunmazken, en yüksek koliform bakteri ezogelin çorbasında tespit edilmiştir (2,10 log kob/g). Escherichia coli bakterisi hiçbir örnekte belirlenmemiştir. İlave olarak, Çorlu, Kırklareli ve Ordu’dan alınmış 3 farklı propolis ektraktları ve 5 farklı antibiyotik hazır çorbadan izole edilmiş S.aureus üzerine inhibitor etkisi incelenmiştir. Üçlü çorbadan izole edilen S. aureus bakterileri kullanılarak, Cefixime ile 36.62 ± 0.17 mm, en küçük zon çapı, Streptomisin (14.74 ± 0.4mm) tespit edildiştir. Ordu, Çorlu ve Kırklareli'den alınan propolis örneklerin zon çapları sırasıyla 10.18 ± 0.04mm, 7.07 ± 0.45 mm ve 6.21 ± 0.14 mm olarak belirlenmiştir. Izole edilen S.aureus bakterilerinin tamamının Amoxicillin’e karşı duyarlı olduğu, propolis örneklerinin ise toplandığı bölgelere göre farklı antimikrobiyal etki gösterdiği tespit edilmiştir

The Effects Of Food-Related Misconception in Printed, Visual and Social Media on the Consumer

Teknolojinin gelişmesi, sanayileşme, eğitim düzeyinin, ekonomik ve sosyal refahın artması insanların gıdalarave sağlıklı beslenmeye olan ilgisini arttırmıştır. Ancak doğru ve yeterli bilgi sahibi olmayan kişilerce yapılanyanlış açıklamalar tüketicide kafa karışıklığına neden olabilmektedir. Bu çalışma, beslenme ile ilgili halkınbilinç düzeyini ölçmek, günümüzün en büyük sorunlarından biri haline gelen bilgi kirliğinin ortadankaldırılması ve doğru bilginin doğru uzman kaynağından elde edilebilmesi konusunda halkınbilinçlendirilmesi amacıyla yapılmıştır. Bu amaçla, sosyal medya üzerinden toplumun farklı kesimlerinden,farklı bölge ve eğitim düzeyinden toplam 616 kişi ile anket yapılmış ve sonuçlar SPSS.20 programı iledeğerlendirilmiştir. Araştırma sonuçlarına göre, tüketici doğru bilgi kaynağını bilemediğinden özelliklemedyadaki bilgi kirliliğinin, onların beslenme konusunda çok daha büyük yanlışlar yapmasına yol açtığı tespitedilmiştir. Yazılı, görsel ve sosyal medyada gıda ile ilgili yorumların alanında uzman olan kişiler tarafındanyapılması dolayısıyla halkın doğru bilgi kaynaklarına yönlendirilmesi çok önemlidir.The development of technology, industrialization, the increase of economic and social prosperity and the level of education, have increased the interest of people in food and healthy nutrition. However, misrepresentations made by the people who do not eligible and have sufficient information on the subject can cause more confusion in the consumer. This study was conducted in order to measure people's level of consciousness about the food and nutrition, to remove the misinformation that has become one of the biggest problems in nowadays and to make the public aware of the correct information from the right experts or the source. For this purpose, a total of 616 people from different parts of the society, different regions and education levels were surveyed via social media, and the results were evaluated with the SPSS.20 program. According to the results of the research, it has been determined that the misinformation in the media caused more confusion among the consumers who does not know the correct source of information. Therefore, it is important that the information about the food and nutrition in written, visual and social media should be given by the experts in the field, so that people may acquire correct information from those platforms

Potential Uses of Propolis in Food Industry

Son yıllarda beslenme bilincinin artmasıyla beraber doğal gıdalara olan talep artmıştır. Tüketicilerin doğal katkılar kullanılarak üretilmiş gıdaları tercih etmesi gıda üretiminde sentetik maddelere alternatif doğal madde arayışlarına hız kazandırmıştır. Bu doğal ürünler arasında yaygın olarak kullanılan arı ürünleri de yer almaktadır. Arı ürünlerinin tümü birçok hastalığın tedavisi amacıyla kullanılmaktadır. Az bilinen arı ürünlerinden biri olan propolisin önemi son yıllarda anlaşılmaya başlanmıştır. Kimyasal kompozisyonu, sahip olduğu bileşenlerin antimikrobiyal, antioksidan, antikanserojen vb. biyolojik aktivitelere sahip olmaları propolisi önemli bir bileşen haline getirmiştir. Antibakteriyel, antifungal, antioksidan nitelikleri ile propolisin gıda muhafazasında kimyasal koruyuculara alternatif bir katkı olması ile ilgili gıda teknolojisi alanında yapılmış çalışmalar bulunmaktadır. Bu derlemede alternatif bir gıda katkı maddesi olabilecek propolisin gıda teknolojisinde uygulamalarına yönelik yapılmış çalışmalar bulunmaktadır.In recent years, consumer consciousness towards healthy nutrition has increased consumer demand for natural foods. Customer demand for foods produced by natural additives has stimulated researches on natural materials that are alternative to synthetic materials in food production. Among these natural products, bee products are extensively used. Bee products have been used to cure several illnesses. Propolis is one of the little known bee products and has become an important ingredient in food industry. Its importance comes mainly from its chemical composition and biological activities like antimicrobial, antioxidant and anticarcinogenic effects. There are favorable researches in food science and technology related with the antibacterial, antifungal, and antioxidant properties of propolis in the field of food preservation as an alternative to chemical preservatives. In this study, studies about propolis as an alternative food additive in food industry are reviewed

Effect of Pump Hygiene on Microbiological Quality of Demijohn Water

Bu araştırmada, Tekirdağ ilinde tüketime sunulan 20 adet (5 marka ve her markadan 4 farklı örnek) damacana içme suyundan; tüketiciye ulaştığı anda, su pompası takıldıktan sonra ve suyun bitimine yakın 3 farklı zamanda numune alınmış ve mikrobiyolojik kalitesindeki değişiklikler belirlenmeye çalışılmıştır. Analiz sonuçlarına göre; toplam mezofilik aerobik bakteri sayısı başlangıçta ortalama 8,36x101 kob/ml olarak tespit edilirken, damacanaya takılan pompa ile bu sayının ortalama 3,43x103 kob/ml seviyelerine çıktığı belirlenmiştir. Koliform bakteriye başlangıçta hiçbir örnekte rastlanmazken, pompa takılması ile örneklerin % 60’ında 15-46 EMS/ml arasında koliform bakteri tespit edilmiştir. Tüketime sunulan damacana suların mikrobiyolojik olarak temiz olduğu, fakat tüketim süresi, pompa hijyeni ve kullanım koşullarına bağlı olarak mikrobiyolojik kontaminasyonun arttığı belirlenmiştir.In this study, twenty demijohn drinking water samples (5 different brands and 4 different samples from every brand) sold in Tekirdağ city of Turkey, were analyzed to determine their microbiological quality. Microbiological analysis of demijohn drinking water samples performed in three stages; 1st: just after delivery of water to consumer, 2nd: after plugging re-usable water pump, and 3rd: from remainder water at the bottom of demijohn. Microbial contamination risks were determined these stages. Average total aerobic mesophilic bacteria counts in water samples were determined as 8,36x101 cfu/ml. By plugging pump, this value increased to a average 3.43x103 cfu/ml. At the begining coliforms were not detected in any water samples. However, coliforms were determined in 60 percent of samples between 15-46 MPN/ml in the samples after using pump. Although microbiologic quality of demijohn waters were at the safety limits, microbial contamination increased due to the consumption period, pump hygiene and usage conditions during the consumption period

Rheological behaviour and yield characterization of gum from local isolates: Xanthomonas hortorum pv. pelargonii and Xanthomonas axonopodis pv. begonia

Xanthan production capacity of local isolates X. hortorum pv. pelargonii and X. axonopodis pv. begonia were investigated by systematically changing fermentation conditions. Optimum yields were found as 11.19 g/L, 9.72 g/L and9.65 g/L and for standard isolate X. campestris DSM 19000, X. hortorum pv. pelargonii and X. axonopodis pv. begonia, respectively. Optimum agitation rate and inoculum volume were found as 180 rpm and 5%. Moreover, better gelforming and thickening properties were obtained for xanthan gum from local isolates. Higher K value was observedfor gum solutions of the local isolates at all concentration when Ostwald de Waele model was used. Activation energies changed between 4.85 and 25.43 kJ/mol and it is the highest for gum from standard isolate. Moreover, K’ andK” values obtained from dynamic rheological analysis were higher for the local isolates than that of standard isolate.The results confirmed that the local isolates appeared to be suitable microorganisms for xanthan gum production

Determination of the changes of antifungal properties of Satureja hortensis, Thymus vulgaris and Thymbra spicata exposed to gamma irradiation

In this research, changes in the antifungal activity of the extract of Satureja hortensis, Thymus vulgaris and Thymbra spicata exposed to gamma irradiation against two aflatoxigenic moulds Aspergillus parasiticus NRRL 2999 and 465 were investigated. The samples of dry plant leaf powder were irradiated with doses of 1.2, 3.0, 5.1 kGy. While the antifungal activity of S. hortensis with 0 and 1.2 kGy dose irradiation against A. parasiticus NRRL 2999 was found to be similar, it decreased with 3.0 and 5.1 kGy irradiation doses (P<0.05). On the contrary, antifungal activity of T spicata increased until 3.0 kGy and then it decreased with 5.1 kGy irradiation dose (P<0.05). For T vulgaris, an increase of irradiation dose resulted in a decrease of antifungal activity against aflatoxigenic moulds. This research shows that antifungal properties of some spices can be changed by gamma irradiation. (C) 2009 Elsevier Ltd. All rights reserved

YAZILI, GÖRSEL VE SOSYAL MEDYADA GIDA İLE İLGİLİ BİLGİ KİRLİLİĞİNİN HALKIN GIDA TERCİHİ ÜZERİNE ETKİLERİ

Teknolojinin gelişmesi, sanayileşme, eğitim düzeyinin, ekonomik ve sosyal refahın artması insanların gıdalarave sağlıklı beslenmeye olan ilgisini arttırmıştır. Ancak doğru ve yeterli bilgi sahibi olmayan kişilerce yapılanyanlış açıklamalar tüketicide kafa karışıklığına neden olabilmektedir. Bu çalışma, beslenme ile ilgili halkınbilinç düzeyini ölçmek, günümüzün en büyük sorunlarından biri haline gelen bilgi kirliğinin ortadankaldırılması ve doğru bilginin doğru uzman kaynağından elde edilebilmesi konusunda halkınbilinçlendirilmesi amacıyla yapılmıştır. Bu amaçla, sosyal medya üzerinden toplumun farklı kesimlerinden,farklı bölge ve eğitim düzeyinden toplam 616 kişi ile anket yapılmış ve sonuçlar SPSS.20 programı iledeğerlendirilmiştir. Araştırma sonuçlarına göre, tüketici doğru bilgi kaynağını bilemediğinden özelliklemedyadaki bilgi kirliliğinin, onların beslenme konusunda çok daha büyük yanlışlar yapmasına yol açtığı tespitedilmiştir. Yazılı, görsel ve sosyal medyada gıda ile ilgili yorumların alanında uzman olan kişiler tarafındanyapılması dolayısıyla halkın doğru bilgi kaynaklarına yönlendirilmesi çok önemlidir.The development of technology, industrialization, the increase of economic and social prosperity and the level of education, have increased the interest of people in food and healthy nutrition. However, misrepresentations made by the people who do not eligible and have sufficient information on the subject can cause more confusion in the consumer. This study was conducted in order to measure people's level of consciousness about the food and nutrition, to remove the misinformation that has become one of the biggest problems in nowadays and to make the public aware of the correct information from the right experts or the source. For this purpose, a total of 616 people from different parts of the society, different regions and education levels were surveyed via social media, and the results were evaluated with the SPSS.20 program. According to the results of the research, it has been determined that the misinformation in the media caused more confusion among the consumers who does not know the correct source of information. Therefore, it is important that the information about the food and nutrition in written, visual and social media should be given by the experts in the field, so that people may acquire correct information from those platforms

Inhibitory effect of propolis (bee gum) against staphylococcus aureus bacteria isolated from instant soups

In this study, microbiological quality of instant soups sold in markets and the antibiotic susceptibility of Staphylococcus aureus isolated from instant soups were examined. Total aerobic mesophilic bacteria and S. aureus counts of 6 different types of instant soups were analyzed. Microbiological analysis was carried out in a total of 72 packages of soups, including three replicates. Total aerobic mesophilic bacteria counts and S. aureus counts were determined to be 3.51–4.53 log cfu/g and 0.93–1.71 log cfu/g, respectively. Coliform bacteria were not detected in any of the tomato soups analyzed. The highest number of coliform bacteria (2.10 log cfu/g) was detected in Ezogelin soups. Escherichia coli was not detected in any of the samples analyzed. In addition, the inhibitory effects of five different antibiotics and three different propolis extracts supplied from three different regions of Turkey (Corlu, Kirklareli and Ordu) were examined against S. aureus isolated from the instant soups. Using S. aureus bacteria isolated from tripe soup, a zone diameter of 36.62±0.17 mm was observed with Cefixime. The smallest zone diameter was obtained with Streptomycin (14.74±0.4mm). Zone diameters with propolis samples from Ordu, Corlu and Kirklareli were 10.18±0.04 mm, 7.07±0.45 mm and 6.21±0.14mm, respectively. All of the S. aureus bacteria isolated were sensitive to the Amoxicillin. Propolis extracts were inhibitory towards S. aureus isolated from instant soups, but propolis samples obtained from different geographical regions showed varying antimicrobial effects. © 2017 Namik Kemal University - Agricultural Faculty. All Rights Reserved

The effect of different doses of UV-C treatment on microbiological quality of bovine milk

In this study, a non-thermal technology for preservation with the use of UV-C (ultraviolet) was examined in bovine milk. After UV-C treatment, the counts of microorganisms naturally found in raw milk and counts in pathogen-inoculated UHT milk were determined. For UV-C treatment, a reactor with a variable flow rate (5 mL/min to 18 mL/min) and temperature range (4°–25°) was designed and the data were modeled using response surface methodology. After UV-C treatment, approximately 2 log decrease in total mesophilic aerobic bacteria count and approximately 4 log decrease in yeast-mold count were achieved in raw milk. For pathogen-inoculated UHT milk, Salmonella Typhimurium (ATCC 14028), Listeria monocytogenes (ATCC 19115), Staphylococcus aureus (ATTC 25923) and Escherichia coli (ATTC 35218) counts were decreased by nearly 2 log, 2.5 log, 2.5 log and 3 log CFU, respectively. Since high-dose UV-C treatment is detrimental to the sensory properties of milk, it can be integrated with existing pasteurization techniques with a reduction in pasteurization temperature rather than as a stand alone alternative to pasteurization of raw milk. © 202020.238; NKÜBAP.03The financial support from NKÜBAP Tekirdag Namik Kemal University Scientific Research Projects Fund (BAP project number: NKÜBAP.03.GA.20.238 ) is gratefully acknowledged.The financial support from NK?BAP Tekirdag Namik Kemal University Scientific Research Projects Fund (BAP project number: NK?BAP.03.GA.20.238) is gratefully acknowledged