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Objective: In this study, the total phenolic content, individual phenolic components, and total antioxidant capacity of the ultrasonically assisted ethanolic extract of propolis were investigated in detail. Another aim of our study was to reveal the effects of propolis extracts on olive oil lipid oxidation compared to synthetic antioxidants (BHA, BHT) with tests performed under accelerated thermal conditions.Material and Method: We determined the total antioxidant capacity of propolis extract by CUPRAC assay. On the other hand, the polyphenolic content of propolis extract was determined by the Folin assay. Identification of phenolic compounds of propolis was performed using reversed phase high performance liquid chromatography (RP-HPLC). The effect of propolis on the oxidative stability of extra virgin olive oil under accelerated storage conditions was studied using the Shall oven test.Result and Discussion: The results revealed that propolis is rich in phenolic components. According to the CUPRAC assay, the total antioxidant capacity of propolis extract was calculated to be 2.013 ± 0.03 mmol TR/g-propolis extract. The total phenolic content of the propolis extract was calculated to be 1.67 ± 0.008 mmol TR/ g-propolis extract. The oils with propolis extract incorporated exhibited much better chemical stability, including lower peroxide value and partly decreased tocopherols content. Data showed that propolis extract was more effective in delaying the oxidation of olive oil compared to synthetic antioxidants such as BHA and BHT., Amaç: Bu çalışmada, propolisin ultrasonik destekli etanolik ekstraktının, toplam fenolik içeriği, bireysel fenolik bileşenleri ve toplam antioksidan kapasitesi ayrıntılı olarak araştırılmıştır. Çalışmamızın diğer bir amacı da propolis ekstraktlarının, zeytinyağı lipid oksidasyonu üzerindeki etkilerini sentetik antioksidanlara (BHA, BHT) kıyasla hızlandırılmış termal koşullar altında yapılan testlerle ortaya koymaktır.Gereç ve Yöntem: Propolis ekstraktının toplam antioksidan kapasitesini CUPRAC metoduna göre belirledik. Diğer taraftan propolis ekstraktının polifenolik içeriği Folin testiyle belirlendi. Propolisin fenolik bileşiklerin tanımlanması ise ters fazlı yüksek performanslı sıvı kromatografisi (RP-HPLC) kullanılarak gerçekleştirildi. Hızlandırılmış depolama koşulları altında, propolisin sızma zeytinyağının oksidatif stabilitesi üzerindeki etkisinin belirlenmesi shall oven testine göre analiz edildi.Sonuç ve Tartışma: Sonuçlar propolisin fenolik bileşenler açısından zengin olduğunu ortaya koydu. CUPRAC tahliline göre propolis ekstraktının toplam antioksidan kapasitesi 2.013 ± 0.03 mmol TR/g-propolis ekstraktı olarak hesaplandı. Propolis ekstraktının toplam fenolik içeriği 1.67 ± 0.008 mmol TR/ g-propolis ekstraktı olarak hesaplandı. Dahil edilen propolis ekstraktlı yağlar, daha düşük peroksit değeri ve kısmen azaltılmış tokoferol içeriği de dahil olmak üzere çok daha iyi kimyasal stabilite sergiledi. Veriler, propolis ekstraktının zeytinyağının oksidasyonunu geciktirmede BHA ve BHT gibi sentetik antioksidanlara kıyasla daha etkili olduğunu gösterdi.

Bu çalışmada yulaf tanelerinin ultrasonik destekli ekstraksiyonu ile elde edilen ekstraktların toplam antioksidan kapasitesi, serbest radikal süpürme aktivetisinin belirlenmesinin yanı sıra yulaf ekstraktının yağ asidi profili ve toplam tokoferol içeriğinin belirlenmesi amaçlandı. Bu amaçla, bakır iyonları (Cu2+) azaltıcı antioksidan güç testi (CUPRAC) metoduna göre yulaf taneleri ekstraktlarının toplam antioksidan kapasitesi belirlendi. Aynı zamanda, 1,1-difenil-2-pikril-hidrazil (DPPH•) yöntemine göre yulaf ekstraktlarının radikal süpürme kapasitesi araştırıldı. Yulaf ekstraktının yağ asidi komposizyonu GC-FID analizlerine göre belirlendi. Toplam tokoferol içeriği ise spektrofotometrik olarak belirlendi. Yulaf taneleri ekstraktının CUPRAC metoduna göre toplam antioksidan kapasitesi 1.5 ± 0.03 mmol TR /100g-yulaf taneleri ekstraktı olarak hesaplandı. Yulaf ekstraktının DPPH• radikali süpürme aktivitesi ise 2.02 ± 0.01 mmol TR /100 g – yulaf ekstraktı olarak hesaplandı. Yulaf özleri, güçlü antioksidan ve radikal süpürme yeteneği sergiledi. GC-FID sonuçları yulaf ekstraktının doymamış yağ asitlerince zengin olduğunu (Oleik asit, %43; Linoleik asit, %34) ortaya çıkardı. Yulaf taneleri ekstraktlarının toplam tokoferol içeriği ise 1376.3 ± 16 mg/kg-yulaf ekstrakt olarak bulundu., In this study, it was aimed to determine the total antioxidant capacity and free radical scavenging activity of the extracts obtained by ultrasonic assisted extraction of oat grains, as well as to determine the fatty acid profile and total tocopherol content of oat extracts. For this purpose, we determined the total antioxidant capacity of oat grains extracts according to the copper ions (Cu2+) reducing antioxidant capacity (CUPRAC) test. At the same time, the radical scavenging capacity of oat extracts was investigated by the 1,1-diphenyl-2-picryl-hydrazil (DPPH•) method. Fatty acid composition of oat extract was determined via GC-FID analysis. Total tocopherol content was determined spectrophotometrically. The total antioxidant capacity of the oat grain extract was calculated as 1.5 ± 0.03 mmol TR 100g-1-oat grains extract by CUPRAC method. The DPPH• radical scavenging activity of the oat extract was calculated as 2.02 ± 0.01 mmol TR 100 g-1 – oat extract. Oat extracts exhibited potent antioxidant and radical scavenging ability. GC-FID results revealed that oat extract was rich in unsaturated fatty acids (Oleic acid, 43%; Linoleic acid, 34%). Total tocopherol content of oat oil extracts was 1376.3 ± 16 mg kg-1-oat extract.

In this study, soft hydrogel layers reinforced withcotton nonwoven were produced to use as a surgical dressing. Solutionconsisting of two polymers (O-carboxymethyl chitosan and polyethylene glycol)were chemically cross-linked using polyethylene glycol diglycidyl ether.Optimum hydrogel formulation was determined considering mechanical parameters. Aftercasting of the selected formulation onto nonwovens, samples were freeze-dried. Toincrease the swelling capacity of the hydrogels, nano/micro-sized cellulose wasadded. Physical features, dynamic fluid handling capacity, water vaporpermeability, morphology (SEM), and chemical structure (FT-IR) were examined. Antibacterialand in vitro cytotoxicity assays wereapplied to the formulation showing the best characteristics.&nbsp

The aim of our study was to evaluate and collate the chemical constituents and antioxidant properties of dry rhizomes of Ginger and dry rhizomes of Turmeric. The assay for quantification of the phenolic compounds in the samples was carried out using the reversed phase-high performance liquid chromatography (RP-HPLC). To determine mineral components in samples inductively coupled plasma optical out flow spectroscopy (ICP-OES) procedure was applied. The most abundant phenolic components in turmeric rhizomes are ferulic acid (93.59 mg), benzoic acid (40.09 mg), vanillin (26.69 mg) and p-coumaric acid (23.25mg) respectively. On the other hand, the most common phenolic components in ginger rhizomes are Benzoic acid (33.31mg), Ferulic acid (11.41 mg) and vanillin (11.83 mg). In addition, ethanolic extract ginger (EEG) and ethanolic extract turmeric (EET) had an effective DPPH• scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power activities. According to ICP-OES analysis results of rhizomes and extracts, the potassium was, quantitatively, the most abundant mineral in samples. Subsequently, sodium, magnesium, phosphorus and calcium were identified, respectively., Çalışmamızın amacı, Zencefilin kuru rizomlarının ve Zerdeçal'ın kuru rizomlarının kimyasal bileşenlerini ve antioksidan özelliklerini değerlendirmek ve harmanlamaktı. Numunelerdeki fenolik bileşiklerin miktar tayini analizi, ters fazlı yüksek performanslı sıvı kromatografisi (RP-HPLC) kullanılarak gerçekleştirilmiştir. Örneklerdeki mineral bileşenlerini belirlemek için endüktif olarak eşleştirilmiş plazma optik çıkış akış spektroskopisi (ICP-OES) prosedürü uygulandı. Zerdeçal rizomlarında en fazla bulunan fenolik bileşenler sırasıyla ferulik asit (93.59 mg), benzoik asit (40.09 mg), vanilin (26.69 mg) ve p-kumarik asittir (23.25 mg). Öte yandan zencefil rizomlarındaki en yaygın fenolik bileşenler Benzoik asit (33.31 mg), Ferulik asit (11.41 mg) ve vanilindir (11.83 mg). Ek olarak, etanolik zencefil özütü (EEG) ve etanolik zerdeçal özütü (EET), etkili bir DPPH• süpürme, hidrojen peroksit süpürme, demir iyonları (Fe3+) azaltıcı güç aktivitelerine sahipti. Rizomların ve etanolik ekstraktların ICP-OES analiz sonuçlarına göre, potasyum kantitatif olarak numunelerde en bol bulunan mineraldi. Daha sonra sırasıyla sodyum, magnezyum, fosfor ve kalsiyum tespit edilmiştir.

Moisture related properties of polyester (PET) / viscose (CV) nonwoven fabrics were investigated in this research. Four different nonwoven fabrics, PCV0, PCV1, PCV2 and PCV3, having different viscose proportion namely 0%, 30%, 50% and 70% were selected, respectively. The manufacturing techniques and fabric thickness values were kept the same for the comparison of tested fabrics. Moisture absorption, vertical water wicking, air and water vapor permeability tests were carried out and also moisture transmission performance of the blended nonwoven fabrics was examined in order to evaluate the effects of fiber ratios on moisture related properties of the blended fabrics. It was determined that higher viscose content in the blended fabrics result in higher vertical water vicking performance of the fabric. The moisture content of the fabrics also increased with increasing viscose proportion. This is most probably because of the high moisture absorption capacity of the viscose fibers. The wetting time and wetting radius results are in reverse ratio with the viscose proportion of the fabrics in moisture management test. It can be also stated that permeability properties depend not only viscose content but also fabric structural parameters.

Copyright © 11th Inter. Conf. on Geos. 2018, ICG 2018. All rights reserved.Geotextiles, which are the members of geosynthetics, are gaining more importance in complex applications such as construction sites and agricultural areas by virtue of their various advantages. Geotextiles are exposed to various loads in their application areas so that the knowledge of their mechanical behavior is a required parameter. In this study, a geometrical model was constructed by using theory of layered composite materials to predict the nonwoven geotextiles mechanical properties. Stress analysis of model was performed in commercial finite element software. Mechanical properties of fibers and constructional parameters of fabrics were used as data in the analysis. The comparison of theoretical and experimental results indicated that, meaningful stress data can be obtained from the stress distribution of computed models. However, it was found that, the difference between computed and measured elongation values was high. Consequently, it can be said that the model can be used as a tool to ease the selection of raw material and product type, and thus it will provide an advantage to the manufacturers in terms of cost and duration of design and production processes.

Cellulose basedmaterials such as vegetable fibers draw attention to be utilizable as filler orreinforcement material particularly for polymers due to their ecologicallyfriendly structure, low density and sustainability. The studies which areperformed in order to enhance the usability of cellulose based fibers asreinforcement materials become essential. In this study, commonly used vegetablefibers for composite materials production such as flax, hemp, coir, sisal,banana and jute fibers were treated with alkali, then chemical composition ofthe fibers were tested, and structural properties of the fibers were analyzedby fourier transform infrared spectroscopy (FTIR), scanning electron microscopy(SEM) and fluorescence microscopy. In case of the analysis results, it isdetermined that alkali modification reduced the content of the non-cellulosiccomponents, changed the fluorescence color of the fibers regarding to thechange in fiber chemical composition andalso roughened the fiber surface by creating cleaning effect on fiber surface., Yenilenebilirve sürdürülebilir üretimi, çevre dostu olması ve düşük yoğunluğu gibiözellikleri nedeni ile selülozik liflerin özellikle polimerik malzemelerde takviyemateryali olarak kullanımı dikkat çekmektedir. Selüloz esaslı liflerin takviyemateryali olarak kullanılabilirliğini geliştirmek amacı ile yapılan çalışmalarönem kazanmaktadır. Bu çalışma kapsamında, kompozit malzeme üretiminde yaygınolarak kullanılan bitkisel liflerden keten, kenevir, Hindistan cevizi, sisal,muz ve jüt liflerinin alkali ile modifikasyonu yapılmış, liflerin içeriklerianaliz edilmiş ve kimyasal yapıları fourier dönüşümlü kızılötesi spektroskopisi(FTIR), morfolojik özellikleri ise taramalı elektron mikroskobu (SEM) vefloresan mikroskop ile incelenmiştir. Analiz sonuçları incelendiğinde, alkaliişlemin lif yüzeyinde temizleme etkisi meydana getirerek lifteki selülozikolmayan bileşenleri azalttığı, lif içeriğinde meydana gelen değişime bağlıolarak verdiği floresan rengi değiştirdiği ve lif yüzeyini pürüzlendirdiğibelirlenmiştir.