Avokado, Plantae krallığına, Lauraceae ailesine, Laurales takımına, Persea cinsine ve P. american... more Avokado, Plantae krallığına, Lauraceae ailesine, Laurales takımına, Persea cinsine ve P. americana türüne ait bir bitkidir. İçeriğindeki zengin biyoaktif bileşenlerin ve besin öğelerinin sağlık üzerine yararlı etkileri olduğu bilinen ve süper gıda olarak kabul edilen bitkisel kaynaklı bir gıdadır. Avokado ağacının; meyvesinin eti ve kabuğu, yaprağı ve çekirdeği zengin biyoaktif bileşenler içermektedir. Meyve çekirdeği (%16) ve kabuğu (%11) bazı çeşitlerde istisnalar olmak üzere meyvenin %21-30’unu temsil eden miktarlarda katı atık oluşturmaktadır. Avokadoda en yaygın bulunan biyoaktif bileşenler polifenoller, karotenoitler, tokoferoller ve sterollerdir. Polifenoller meyve eti, kabuk, tohum ve yapraklarda; karotenoitler ve tokoferoller ise avokado meyvesinin etinde bulunmaktadır. Avokadonun zengin biyoaktif içeriğinin metabolik sendrom hastalıklarına, hipoglisemik, antihipertansif, antioksidan, obezite, hiperlipidemik, antimikrobiyal, antiprotozoal ve antimikobakteriyel vb. hastalıkl...
Avocado leaves, typically considered as pruning residues, possess a significant amount of bioacti... more Avocado leaves, typically considered as pruning residues, possess a significant amount of bioactive compounds. This research aimed to optimize the extraction of phenolic compounds from Hass avocado leaves using microwave-assisted extraction (MAE) and response surface method (RSM). The extraction yield and total phenolic content (TPC) were maximized by determining the optimal process conditions, which were found to be 47°C for 5 minutes and a solid/solvent ratio of 1.13 g dry leaf/100 mL, respectively. The predicted values of all models were found to be statistically significant (p <0.001). The aqueous extracts' antidiabetic and antioxidant activities were 64.59% and 235.6 mg TE/100 g, respectively. The amount of TPC was 591.76 μg GAE/g extract, and chlorogenic acid was the main phenolic component. These results indicated that MAE proved efficient with low energy consumption, yielding phenolic-rich avocado leaf extracts, which possess high antioxidant and antidiabetic activities.
Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahipt... more Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahiptir. Zeytinyağı kalitesi ve bileşimi çeşit, coğrafi alan, iklim, çevresel faktörler, olgunlaşma, ekstraksiyon ve yağ depolaması gibi birçok faktöre bağlı olarak değişim göstermektedir. Yüksek yağ verimine sahip ve sterol bileşenleri bakımından zengin natürel sızma zeytinyağı üretimi gıda sanayiinde önemli bir yere sahiptir. Zeytinyağı üretimi aşamasında yoğurma koşulları, kalite parametreleri üzerinde oldukça etkilidir. Bu derlemede zeytin çeşidi, coğrafi alan, olgunluk derecesi ve farklı yoğurma koşullarının zeytinyağının sterol profili üzerine etkisine yer verilmiştir. Yapılan çalışmalar sonucu olgunlaşma süresince toplam sterol miktarı, Δ-5-avenasterol, kampesterol bileşen miktarlarının genelde arttığı, toplam sterol ve βsitosterol miktarının ise azaldığı tespit edilmiştir. Yoğurma parametrelerinin etkisi incelendiğinde ise yüksek sıcaklık ve süre uygulamalarının zeytinyağının sterol profilini olumsuz yönde etkilediği tespit edilmiştir.
Phenolic compounds, related to antioxidative and antifungal properties of ethanolic extracts from... more Phenolic compounds, related to antioxidative and antifungal properties of ethanolic extracts from five commercial grape cultivars (three red and two white) grown in Turkey were determined. A reversedphase high performance liquid chromatography (RP-HPLC) procedure was developed, and a total 18 different phenolic compounds were identified. Total phenolic contents of the extracts were determined using Folin-Ciocalteau method. Antioxidant activities of the extracts were evaluated by using DPPH radical scavenging and phosphomolybdenum methods. All extracts exhibited strong antioxidant and antiradical activity. Phenolic compounds and antioxidant activities of the extracts were variety dependent. Antifungal activities of the pomaces and extracts were screened by both in vitro agar-well diffusion assay and antifungal activity in apple and orange juices in situ using Zygosaccharomyces rouxii and Z. bailii. Antifungal activities revealed that the pomaces and extracts of Gamay and Kalecik karasi could be more effective antifungal agents than those of Emir, Narince and Okuzgozu grape cultivars.
The antimicrobial effect of 11 selected Turkish spice essential oils was investigated against sev... more The antimicrobial effect of 11 selected Turkish spice essential oils was investigated against seventeen pathogenic bacteria. The antimicrobial activity of the essential oils of six spices (cumin, fennel, laurel, mint, marjoram, oregano, pickling herb, sage, savory, thyme (black) and thyme) was tested at four concentrations (0.2, 0.4, 1 and 2%) on various microorganisms ( E. aerogenes, E. coli, E. coli O157:H7, K. pneumoniae, P. vulgaris, S. enteritidis, S. gallinarum, S. typhimurium, S. aureus, Y. enterocolitica, A. hydrophila, C. xerosis, M. luteus, M. smegmatis, E. feacalis, P. aeruginosa and P. fluorescens). All preparations showed antibacterial activity against at least one or more bacteria. The inhibitory effect of the essential oils was evaluated through paper disc diffusion method. In general, the essential oils at 1 and 2% levels were effective. The most active essential oils were marjoram, thyme and oregano. According to the results, the studied essential oils potentially m...
In this study, total contents of phenolic, flavanol and flavonol, antioxidant activities and anti... more In this study, total contents of phenolic, flavanol and flavonol, antioxidant activities and antimicrobial activities of the Turkish endemic Salvia pisidica Boiss. & Heldr. ex Bentham (Lamiaceae) extract and essential oil were assessed in vitro. Total phenolic, flavanol and flavonol contents in the extract were 54.57 mg gallic acid equivalents (GAE)/g, 16.70 mg catechine equivalents (CE)/g and 18.19 mg rutin equivalents (RE)/g, respectively. Antioxidant activities (IC 50 value) of the extract and essential oil were determined as 4.88 and 6.41 mg/mL by DPPH assay, respectively. 31 compounds were determined in the essential oil using GC-MS and the major compounds (%) were camphor (23.76), sabinol (19.2), a-thujone (14.2) and eucalyptol (1.8-cineole) (5.8). The antimicrobial activity of the methanolic extract and the essential oil against 13 bacterial and two yeast strains was determined. The extract (concentration 5 g/100 ml or 10 g/100 ml) was effective against most of the strains tested, yet not against Bacillus cereus, Staphylococcus aureus, Aeromonas hydrophila and the two yeast strains tested. The essential oil (2 g/100 ml) showed an antimicrobial effect against all the gram (þ) bacteria tested, against Saccharomyces cerevisiae, but was not effective against all gram (À) bacteria and Candida albicans. These results show that S.piscidica essential oil and extract could be considered as a natural alternative to traditional food preservatives and be used to enhance food safety and shelf life.
Eighteen extracts of spices commonly consumed worldwide and grown naturally in Turkey were tested... more Eighteen extracts of spices commonly consumed worldwide and grown naturally in Turkey were tested against twenty three bacterial strains to compare their antibacterial effects with eleven antibiotics. Eight pathogens and fifteen lactobacilli isolated from chick intestine were used as the test microorganisms. Pathogens (six different Staphylococcus aureus strains, Escherichia coli ATCC 25922 and Yersinia enterocolitica ATCC 1501) were grown in Nutrient broth and lactobacilli in MRS broth. Hop extracts formed inhibition zones against S. aureus strains of upto 36 mm. Inhibitory effects of hop extracts against S. aureuswere generally higher than that of erythromycin as antibiotic. Helichrysum compactum extract produced an inhibition zone of 23mm to E. coli ATCC 25922 and 26mm to Y. enterocolitica ATCC 1501. Helichrysum compactum extract inhibited the growth of Y. enterocolitica ATCC 1501 more than other spice extracts. While inhibition zones of these extracts against lactobacilli were f...
The total phenolic contents and the essential oil compositions of the previously unknown Stachys ... more The total phenolic contents and the essential oil compositions of the previously unknown Stachys taxa (Labiatae), including Stachys pinardii Boiss, Stachys cretica L. subsp. mersinaea (Boiss.) Rech., and Stachys aleurites Boiss. &amp;amp;amp;amp;amp;amp;amp;amp; Heldr., all endemic to Turkey, were studied. Their essential oil compositions were investigated by GC-MS. It was found that the main constituents were α-curcumene (34.10%) for S. cretica,
Rosa damascena Mill. is one of the most important Rosa species for the flavour and fragrance indu... more Rosa damascena Mill. is one of the most important Rosa species for the flavour and fragrance industries. The high amount of residues of spent flowers after steam distillation and the potential use of their essential oils as natural antioxidants and antimicrobials lead to determine the antioxidant and antibacterial activities of fresh and spent Rosa damascena flower extracts. The total phenolic contents were 276.02±2.93mg gallic acid equivalent (GAE)/g in FF (fresh flower) extract and 248.97±2.96mg GAE/g in SF (spent flower) extract. FF and SF extracts showed 74.51±1.65 and 75.94±1.72% antiradical activities at 100ppm. The antioxidant activity of FF extract (372.26±0.96mg/g) was higher than that of SF extract (351.36± 0.84mg/g). Antibacterial activity of the extracts was determined by the agar diffusion method against 15 species of bacteria: Aeromonas hydrophila, Bacillus cereus, Enterobacter aerogenes, Enterococcus feacalis, Escherichia coli, Escherichia coli O157:H7, Klebsiella pne...
Chestnut (Castanea sativa), also known as sweet chestnut or European chestnut, belongs to the bot... more Chestnut (Castanea sativa), also known as sweet chestnut or European chestnut, belongs to the botanical family of Fagaceae. The high contribution to the world production of this fruit is mainly originated from China, Bolivia and Turkey. Chestnut promises health and nutritional benefits for consumers due to its rich nutrients including dietary fibers, minerals, essential fatty acids, vitamins, essential amino acids, antioxidants and other important bioactive components. Leaves, bark, twigs and nuts are the available parts for usage. Chestnut is commonly consumed as a raw and/or in a roasted form. Additionally, chestnut flour takes place in food markets as another popular and alternative product. According to the literature, low-fat content was reported for chestnuts. However, the valuable nutritional composition of chestnut oil leads interests to these nuts as a potential oil source. Chestnut oil is rich in omega fatty acids such as linoleic and oleic acids, in tocopherols such as γ-tocopherol, which contribute to human health. The current chapter serves as a guide which presents the history of chestnuts oil from past to today to shape the future studies.
Various fixed oils (refined and unrefined), namely drying oils or seed oils, are commonly used as... more Various fixed oils (refined and unrefined), namely drying oils or seed oils, are commonly used as medium in pictorial art and these oils are preferred by artists in order to dry and bind the color pigments in a canvas. The effects drying oils on characteristics (color change in time, required time for complete drying, constituents paint medium and cracking etc.) of paint vary depending on the fatty acid composition of the oil. However, studies about the effects of refined and cold press (unrefined) seed oils on aforementioned properties of paint are insufficient, thus in the present study, four different fixed oils (linseed, sunflowers, safflowers and sesame oils) were mixed with color pigments (white, red, yellow and blue) with the ratio of 1:10 (w/v) until getting a creamy structure and their effects on total drying time, color attributes (L*, a*, b*) were investigated. Moreover, fatty acid compositions (area %) of used drying oils are presented according to the GC/FID results. Co...
Özet: Bu çalışmada Muğla İli Yatağan İlçesi'nde yetiştirilen Memecik çeşidi zeytin meyveleri ... more Özet: Bu çalışmada Muğla İli Yatağan İlçesi'nde yetiştirilen Memecik çeşidi zeytin meyveleri kullanılmıştır. Hasat edilen meyvelerin olgunluk indeksi 4.91 olarak belirlenmiştir. Hasat edilen meyve örneklerinde ilk olarak fiziksel ve fiziko-kimyasal özelliklerin tespitine yönelik analizler yapılmıştır. Daha sonra farklı sıcaklık, süre ve altın çilek miktarları kullanılarak merkezi karma tasarım ile elde edilen deneme desenine göre altın çilek çeşnili zeytinyağları üretilmiştir. Zeytinyağı üretim prosesinin yoğurma aşamasında lif içeriği yüksek ve kendine has aromaya sahip kurutulmuş altın çilek meyveleri zeytin hamuruna ilave edilerek zeytinyağı verimi ve kalite parametreleri üzerine etkisi araştırılmıştır. Ayrıca yoğurma prosesinde farklı sıcaklık, süre ve altın çilek konsantrasyonları kullanılarak sonuçların optimizasyonu gerçekleştirilmiştir. Elde edilen altın çilek çeşnili zeytinyağlarında UV ışınında özgül absorbans değerleri (K 232 , K 270), serbest asitlik ve peroksit değe...
Magneto-convection can produce an active region without an initial coherent flux tube. A simulati... more Magneto-convection can produce an active region without an initial coherent flux tube. A simulation was performed where uniform, untwisted, horizontal magnetic field of 1 kG strenght was advected into the bottom of a computational domain 48 Mm wide by 20 Mm deep. The up and down convective motions produce a hierarchy of magnetic loops with a wide range of scales, with smaller loops riding "piggy back" in a serpentine fashion on larger loops. When a large loop approaches the surface it produces an small active region with a compact leading spot and more diffuse following spots.
Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahipt... more Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahiptir. Zeytinyağı kalitesi ve bileşimi çeşit, coğrafi alan, iklim, çevresel faktörler, olgunlaşma, ekstraksiyon ve yağ depolaması gibi birçok faktöre bağlı olarak değişim göstermektedir. Yüksek yağ verimine sahip ve sterol bileşenleri bakımından zengin natürel sızma zeytinyağı üretimi gıda sanayiinde önemli bir yere sahiptir. Zeytinyağı üretimi aşamasında yoğurma koşulları, kalite parametreleri üzerinde oldukça etkilidir. Bu derlemede zeytin çeşidi, coğrafi alan, olgunluk derecesi ve farklı yoğurma koşullarının zeytinyağının sterol profili üzerine etkisine yer verilmiştir. Yapılan çalışmalar sonucu olgunlaşma süresince toplam sterol miktarı, Δ-5-avenasterol, kampesterol bileşen miktarlarının genelde arttığı, toplam sterol ve βsitosterol miktarının ise azaldığı tespit edilmiştir. Yoğurma parametrelerinin etkisi incelendiğinde ise yüksek sıcaklık ve süre uygulamalarının zeytinyağının sterol profilini olumsuz yönde etkilediği tespit edilmiştir.
Bu calismada Mugla Ili Yatagan Ilcesi’nde yetistirilen Memecik cesidi zeytin meyveleri kullanilmi... more Bu calismada Mugla Ili Yatagan Ilcesi’nde yetistirilen Memecik cesidi zeytin meyveleri kullanilmistir. Hasat edilen meyvelerin olgunluk indeksi 4.91 olarak belirlenmistir. Hasat edilen meyve orneklerinde ilk olarak fiziksel ve fiziko-kimyasal ozelliklerin tespitine yonelik analizler yapilmistir. Daha sonra farkli sicaklik, sure ve altin cilek miktarlari kullanilarak merkezi karma tasarim ile elde edilen deneme desenine gore altin cilek cesnili zeytinyaglari uretilmistir. Zeytinyagi uretim prosesinin yogurma asamasinda lif icerigi yuksek ve kendine has aromaya sahip kurutulmus altin cilek meyveleri zeytin hamuruna ilave edilerek zeytinyagi verimi ve kalite parametreleri uzerine etkisi arastirilmistir. Ayrica yogurma prosesinde farkli sicaklik, sure ve altin cilek konsantrasyonlari kullanilarak sonuclarin optimizasyonu gerceklestirilmistir. Elde edilen altin cilek cesnili zeytinyaglarinda UV isininda ozgul absorbans degerleri (K232, K270), serbest asitlik ve peroksit degerleri saptanm...
Avokado, Plantae krallığına, Lauraceae ailesine, Laurales takımına, Persea cinsine ve P. american... more Avokado, Plantae krallığına, Lauraceae ailesine, Laurales takımına, Persea cinsine ve P. americana türüne ait bir bitkidir. İçeriğindeki zengin biyoaktif bileşenlerin ve besin öğelerinin sağlık üzerine yararlı etkileri olduğu bilinen ve süper gıda olarak kabul edilen bitkisel kaynaklı bir gıdadır. Avokado ağacının; meyvesinin eti ve kabuğu, yaprağı ve çekirdeği zengin biyoaktif bileşenler içermektedir. Meyve çekirdeği (%16) ve kabuğu (%11) bazı çeşitlerde istisnalar olmak üzere meyvenin %21-30’unu temsil eden miktarlarda katı atık oluşturmaktadır. Avokadoda en yaygın bulunan biyoaktif bileşenler polifenoller, karotenoitler, tokoferoller ve sterollerdir. Polifenoller meyve eti, kabuk, tohum ve yapraklarda; karotenoitler ve tokoferoller ise avokado meyvesinin etinde bulunmaktadır. Avokadonun zengin biyoaktif içeriğinin metabolik sendrom hastalıklarına, hipoglisemik, antihipertansif, antioksidan, obezite, hiperlipidemik, antimikrobiyal, antiprotozoal ve antimikobakteriyel vb. hastalıkl...
Avocado leaves, typically considered as pruning residues, possess a significant amount of bioacti... more Avocado leaves, typically considered as pruning residues, possess a significant amount of bioactive compounds. This research aimed to optimize the extraction of phenolic compounds from Hass avocado leaves using microwave-assisted extraction (MAE) and response surface method (RSM). The extraction yield and total phenolic content (TPC) were maximized by determining the optimal process conditions, which were found to be 47°C for 5 minutes and a solid/solvent ratio of 1.13 g dry leaf/100 mL, respectively. The predicted values of all models were found to be statistically significant (p <0.001). The aqueous extracts' antidiabetic and antioxidant activities were 64.59% and 235.6 mg TE/100 g, respectively. The amount of TPC was 591.76 μg GAE/g extract, and chlorogenic acid was the main phenolic component. These results indicated that MAE proved efficient with low energy consumption, yielding phenolic-rich avocado leaf extracts, which possess high antioxidant and antidiabetic activities.
Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahipt... more Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahiptir. Zeytinyağı kalitesi ve bileşimi çeşit, coğrafi alan, iklim, çevresel faktörler, olgunlaşma, ekstraksiyon ve yağ depolaması gibi birçok faktöre bağlı olarak değişim göstermektedir. Yüksek yağ verimine sahip ve sterol bileşenleri bakımından zengin natürel sızma zeytinyağı üretimi gıda sanayiinde önemli bir yere sahiptir. Zeytinyağı üretimi aşamasında yoğurma koşulları, kalite parametreleri üzerinde oldukça etkilidir. Bu derlemede zeytin çeşidi, coğrafi alan, olgunluk derecesi ve farklı yoğurma koşullarının zeytinyağının sterol profili üzerine etkisine yer verilmiştir. Yapılan çalışmalar sonucu olgunlaşma süresince toplam sterol miktarı, Δ-5-avenasterol, kampesterol bileşen miktarlarının genelde arttığı, toplam sterol ve βsitosterol miktarının ise azaldığı tespit edilmiştir. Yoğurma parametrelerinin etkisi incelendiğinde ise yüksek sıcaklık ve süre uygulamalarının zeytinyağının sterol profilini olumsuz yönde etkilediği tespit edilmiştir.
Phenolic compounds, related to antioxidative and antifungal properties of ethanolic extracts from... more Phenolic compounds, related to antioxidative and antifungal properties of ethanolic extracts from five commercial grape cultivars (three red and two white) grown in Turkey were determined. A reversedphase high performance liquid chromatography (RP-HPLC) procedure was developed, and a total 18 different phenolic compounds were identified. Total phenolic contents of the extracts were determined using Folin-Ciocalteau method. Antioxidant activities of the extracts were evaluated by using DPPH radical scavenging and phosphomolybdenum methods. All extracts exhibited strong antioxidant and antiradical activity. Phenolic compounds and antioxidant activities of the extracts were variety dependent. Antifungal activities of the pomaces and extracts were screened by both in vitro agar-well diffusion assay and antifungal activity in apple and orange juices in situ using Zygosaccharomyces rouxii and Z. bailii. Antifungal activities revealed that the pomaces and extracts of Gamay and Kalecik karasi could be more effective antifungal agents than those of Emir, Narince and Okuzgozu grape cultivars.
The antimicrobial effect of 11 selected Turkish spice essential oils was investigated against sev... more The antimicrobial effect of 11 selected Turkish spice essential oils was investigated against seventeen pathogenic bacteria. The antimicrobial activity of the essential oils of six spices (cumin, fennel, laurel, mint, marjoram, oregano, pickling herb, sage, savory, thyme (black) and thyme) was tested at four concentrations (0.2, 0.4, 1 and 2%) on various microorganisms ( E. aerogenes, E. coli, E. coli O157:H7, K. pneumoniae, P. vulgaris, S. enteritidis, S. gallinarum, S. typhimurium, S. aureus, Y. enterocolitica, A. hydrophila, C. xerosis, M. luteus, M. smegmatis, E. feacalis, P. aeruginosa and P. fluorescens). All preparations showed antibacterial activity against at least one or more bacteria. The inhibitory effect of the essential oils was evaluated through paper disc diffusion method. In general, the essential oils at 1 and 2% levels were effective. The most active essential oils were marjoram, thyme and oregano. According to the results, the studied essential oils potentially m...
In this study, total contents of phenolic, flavanol and flavonol, antioxidant activities and anti... more In this study, total contents of phenolic, flavanol and flavonol, antioxidant activities and antimicrobial activities of the Turkish endemic Salvia pisidica Boiss. & Heldr. ex Bentham (Lamiaceae) extract and essential oil were assessed in vitro. Total phenolic, flavanol and flavonol contents in the extract were 54.57 mg gallic acid equivalents (GAE)/g, 16.70 mg catechine equivalents (CE)/g and 18.19 mg rutin equivalents (RE)/g, respectively. Antioxidant activities (IC 50 value) of the extract and essential oil were determined as 4.88 and 6.41 mg/mL by DPPH assay, respectively. 31 compounds were determined in the essential oil using GC-MS and the major compounds (%) were camphor (23.76), sabinol (19.2), a-thujone (14.2) and eucalyptol (1.8-cineole) (5.8). The antimicrobial activity of the methanolic extract and the essential oil against 13 bacterial and two yeast strains was determined. The extract (concentration 5 g/100 ml or 10 g/100 ml) was effective against most of the strains tested, yet not against Bacillus cereus, Staphylococcus aureus, Aeromonas hydrophila and the two yeast strains tested. The essential oil (2 g/100 ml) showed an antimicrobial effect against all the gram (þ) bacteria tested, against Saccharomyces cerevisiae, but was not effective against all gram (À) bacteria and Candida albicans. These results show that S.piscidica essential oil and extract could be considered as a natural alternative to traditional food preservatives and be used to enhance food safety and shelf life.
Eighteen extracts of spices commonly consumed worldwide and grown naturally in Turkey were tested... more Eighteen extracts of spices commonly consumed worldwide and grown naturally in Turkey were tested against twenty three bacterial strains to compare their antibacterial effects with eleven antibiotics. Eight pathogens and fifteen lactobacilli isolated from chick intestine were used as the test microorganisms. Pathogens (six different Staphylococcus aureus strains, Escherichia coli ATCC 25922 and Yersinia enterocolitica ATCC 1501) were grown in Nutrient broth and lactobacilli in MRS broth. Hop extracts formed inhibition zones against S. aureus strains of upto 36 mm. Inhibitory effects of hop extracts against S. aureuswere generally higher than that of erythromycin as antibiotic. Helichrysum compactum extract produced an inhibition zone of 23mm to E. coli ATCC 25922 and 26mm to Y. enterocolitica ATCC 1501. Helichrysum compactum extract inhibited the growth of Y. enterocolitica ATCC 1501 more than other spice extracts. While inhibition zones of these extracts against lactobacilli were f...
The total phenolic contents and the essential oil compositions of the previously unknown Stachys ... more The total phenolic contents and the essential oil compositions of the previously unknown Stachys taxa (Labiatae), including Stachys pinardii Boiss, Stachys cretica L. subsp. mersinaea (Boiss.) Rech., and Stachys aleurites Boiss. &amp;amp;amp;amp;amp;amp;amp;amp; Heldr., all endemic to Turkey, were studied. Their essential oil compositions were investigated by GC-MS. It was found that the main constituents were α-curcumene (34.10%) for S. cretica,
Rosa damascena Mill. is one of the most important Rosa species for the flavour and fragrance indu... more Rosa damascena Mill. is one of the most important Rosa species for the flavour and fragrance industries. The high amount of residues of spent flowers after steam distillation and the potential use of their essential oils as natural antioxidants and antimicrobials lead to determine the antioxidant and antibacterial activities of fresh and spent Rosa damascena flower extracts. The total phenolic contents were 276.02±2.93mg gallic acid equivalent (GAE)/g in FF (fresh flower) extract and 248.97±2.96mg GAE/g in SF (spent flower) extract. FF and SF extracts showed 74.51±1.65 and 75.94±1.72% antiradical activities at 100ppm. The antioxidant activity of FF extract (372.26±0.96mg/g) was higher than that of SF extract (351.36± 0.84mg/g). Antibacterial activity of the extracts was determined by the agar diffusion method against 15 species of bacteria: Aeromonas hydrophila, Bacillus cereus, Enterobacter aerogenes, Enterococcus feacalis, Escherichia coli, Escherichia coli O157:H7, Klebsiella pne...
Chestnut (Castanea sativa), also known as sweet chestnut or European chestnut, belongs to the bot... more Chestnut (Castanea sativa), also known as sweet chestnut or European chestnut, belongs to the botanical family of Fagaceae. The high contribution to the world production of this fruit is mainly originated from China, Bolivia and Turkey. Chestnut promises health and nutritional benefits for consumers due to its rich nutrients including dietary fibers, minerals, essential fatty acids, vitamins, essential amino acids, antioxidants and other important bioactive components. Leaves, bark, twigs and nuts are the available parts for usage. Chestnut is commonly consumed as a raw and/or in a roasted form. Additionally, chestnut flour takes place in food markets as another popular and alternative product. According to the literature, low-fat content was reported for chestnuts. However, the valuable nutritional composition of chestnut oil leads interests to these nuts as a potential oil source. Chestnut oil is rich in omega fatty acids such as linoleic and oleic acids, in tocopherols such as γ-tocopherol, which contribute to human health. The current chapter serves as a guide which presents the history of chestnuts oil from past to today to shape the future studies.
Various fixed oils (refined and unrefined), namely drying oils or seed oils, are commonly used as... more Various fixed oils (refined and unrefined), namely drying oils or seed oils, are commonly used as medium in pictorial art and these oils are preferred by artists in order to dry and bind the color pigments in a canvas. The effects drying oils on characteristics (color change in time, required time for complete drying, constituents paint medium and cracking etc.) of paint vary depending on the fatty acid composition of the oil. However, studies about the effects of refined and cold press (unrefined) seed oils on aforementioned properties of paint are insufficient, thus in the present study, four different fixed oils (linseed, sunflowers, safflowers and sesame oils) were mixed with color pigments (white, red, yellow and blue) with the ratio of 1:10 (w/v) until getting a creamy structure and their effects on total drying time, color attributes (L*, a*, b*) were investigated. Moreover, fatty acid compositions (area %) of used drying oils are presented according to the GC/FID results. Co...
Özet: Bu çalışmada Muğla İli Yatağan İlçesi'nde yetiştirilen Memecik çeşidi zeytin meyveleri ... more Özet: Bu çalışmada Muğla İli Yatağan İlçesi'nde yetiştirilen Memecik çeşidi zeytin meyveleri kullanılmıştır. Hasat edilen meyvelerin olgunluk indeksi 4.91 olarak belirlenmiştir. Hasat edilen meyve örneklerinde ilk olarak fiziksel ve fiziko-kimyasal özelliklerin tespitine yönelik analizler yapılmıştır. Daha sonra farklı sıcaklık, süre ve altın çilek miktarları kullanılarak merkezi karma tasarım ile elde edilen deneme desenine göre altın çilek çeşnili zeytinyağları üretilmiştir. Zeytinyağı üretim prosesinin yoğurma aşamasında lif içeriği yüksek ve kendine has aromaya sahip kurutulmuş altın çilek meyveleri zeytin hamuruna ilave edilerek zeytinyağı verimi ve kalite parametreleri üzerine etkisi araştırılmıştır. Ayrıca yoğurma prosesinde farklı sıcaklık, süre ve altın çilek konsantrasyonları kullanılarak sonuçların optimizasyonu gerçekleştirilmiştir. Elde edilen altın çilek çeşnili zeytinyağlarında UV ışınında özgül absorbans değerleri (K 232 , K 270), serbest asitlik ve peroksit değe...
Magneto-convection can produce an active region without an initial coherent flux tube. A simulati... more Magneto-convection can produce an active region without an initial coherent flux tube. A simulation was performed where uniform, untwisted, horizontal magnetic field of 1 kG strenght was advected into the bottom of a computational domain 48 Mm wide by 20 Mm deep. The up and down convective motions produce a hierarchy of magnetic loops with a wide range of scales, with smaller loops riding "piggy back" in a serpentine fashion on larger loops. When a large loop approaches the surface it produces an small active region with a compact leading spot and more diffuse following spots.
Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahipt... more Zeytinyağı, besinsel ve diyetetik özelliklerinden dolayı Akdeniz diyetinde önemli bir yere sahiptir. Zeytinyağı kalitesi ve bileşimi çeşit, coğrafi alan, iklim, çevresel faktörler, olgunlaşma, ekstraksiyon ve yağ depolaması gibi birçok faktöre bağlı olarak değişim göstermektedir. Yüksek yağ verimine sahip ve sterol bileşenleri bakımından zengin natürel sızma zeytinyağı üretimi gıda sanayiinde önemli bir yere sahiptir. Zeytinyağı üretimi aşamasında yoğurma koşulları, kalite parametreleri üzerinde oldukça etkilidir. Bu derlemede zeytin çeşidi, coğrafi alan, olgunluk derecesi ve farklı yoğurma koşullarının zeytinyağının sterol profili üzerine etkisine yer verilmiştir. Yapılan çalışmalar sonucu olgunlaşma süresince toplam sterol miktarı, Δ-5-avenasterol, kampesterol bileşen miktarlarının genelde arttığı, toplam sterol ve βsitosterol miktarının ise azaldığı tespit edilmiştir. Yoğurma parametrelerinin etkisi incelendiğinde ise yüksek sıcaklık ve süre uygulamalarının zeytinyağının sterol profilini olumsuz yönde etkilediği tespit edilmiştir.
Bu calismada Mugla Ili Yatagan Ilcesi’nde yetistirilen Memecik cesidi zeytin meyveleri kullanilmi... more Bu calismada Mugla Ili Yatagan Ilcesi’nde yetistirilen Memecik cesidi zeytin meyveleri kullanilmistir. Hasat edilen meyvelerin olgunluk indeksi 4.91 olarak belirlenmistir. Hasat edilen meyve orneklerinde ilk olarak fiziksel ve fiziko-kimyasal ozelliklerin tespitine yonelik analizler yapilmistir. Daha sonra farkli sicaklik, sure ve altin cilek miktarlari kullanilarak merkezi karma tasarim ile elde edilen deneme desenine gore altin cilek cesnili zeytinyaglari uretilmistir. Zeytinyagi uretim prosesinin yogurma asamasinda lif icerigi yuksek ve kendine has aromaya sahip kurutulmus altin cilek meyveleri zeytin hamuruna ilave edilerek zeytinyagi verimi ve kalite parametreleri uzerine etkisi arastirilmistir. Ayrica yogurma prosesinde farkli sicaklik, sure ve altin cilek konsantrasyonlari kullanilarak sonuclarin optimizasyonu gerceklestirilmistir. Elde edilen altin cilek cesnili zeytinyaglarinda UV isininda ozgul absorbans degerleri (K232, K270), serbest asitlik ve peroksit degerleri saptanm...
Uploads
Papers by Gülcan Özkan