Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2025Sensory and physicochemical characteristics of mulberry leathers enriched with sesame, almond, sunflower seeds, coconut, and peanut
Küçük, Murat; Baltaci, Cemalettin; İlyasoğlu, Huri; Karpuz, Omer; Yilmaz, Firat; Kılınç, Kagan; Güler, Burak; Topkaya, Gamze
This study aimed to investigate the utilization of sesame, sunflower seed, almond, peanut, and coconut as condiments for the enrichment of mulberry leather, known locally as mulberry pestil. The investigation involved a comprehensive analysis encompassing proximate composition, mineral content, color, physicochemical, and sensory properties. The studied parameters of enriched samples were compared with those of the plain sample. Employing multivariate statistical techniques enabled the differentiation of the enriched leather samples. Consequently, the leather samples were categorized into three groups by the principal component analysis according to their physicochemical and chemical attributes. Strong positive correlations were observed among the studied parameters, as indicated by Spearman's rank correlation coefficients. The physicochemical and chemical properties of enriched samples exhibited substantial variability. The enriched products had abundant calcium, potassium, magnesium, iron, and zinc levels. These findings revealed that incorporating these condiments enhanced the nutritional values of leather samples, especially in terms of minerals. 100 g of the enriched mulberry leathers had 68.0-70.7 g of carbohydrate, 4.6-5.7 g of protein, 3.6-5.9 g of fat, and 336-359 kcal of energy value. The enriched products might be proposed to provide nutrients and energy in emergencies, especially for adolescents and people affected by disasters.
- MakaleYalnız künye2017Türkiye’ de marketlerde satılan alkolsüz içeceklerin etanol seviyeleri
Burnaz, Nesibe Arslan; Küçük, Murat; Doğan, Hacer; Alkan Türkuçar, Semra; Dolu, Ömer Faruk; Alevci, Aylin; Aktaş Karaçelık, Ayça; Polat, Damla
Etanol, birçok farklı alanda kullanılan temel kimyasallardan biri olmasına rağmen, diyetle alındığında sarhoş edici ve zararlı etkileri yüzünden tıbbi, sosyal ve dini konular bakımından önemli tartışma konularından biri olmuştur. Gıdalardaki ve içeceklerdeki etanolün varlığı, miktarı ve etkilerinin kontrolü önemli araştırma alanlarındandır. Alkolsüz içeceklerle ilgili düzenlemeler ülkeden ülkeye farklılık gösterir. Türkiye’de Türk Gıda Kodeksi Alkolsüz İçecekler Tebliği’ne (2007/26) göre izin verilen en yüksek etanol miktarı 3,0 g/L’dir. Kodekse göre, hacimce % 0,3’ den daha az etanol içeren içecekler, alkolsüz içecekler olarak tanımlanır. Bu çalışmada; kolalar, portakallı sodalar, %100 meyve suları, meyve nektarları, meyve aromalı sodalar, enerji içecekleri, ayran ve kefirin bilinen markaları alkolsüz içecek test numunesi olarak kullanıldı. Bu amaçla, Türk Standartları Enstitüsü’nün TS 1594 Meyve ve Sebze Ürünleri Etanol Muhtevası Tayininin Titrimetrik Yöntemi bir değişiklik yapılarak kullanıldı. Numunelerdeki etanol Clevenger tipi destilasyon aparatıyla hidrodestilasyonla destillendi, ki bu uygulama yöntemi daha uygulanabilir hale getirmiştir. Numunelerde bulunan en yüksek binde etanol konsantrasyonları sırayla kolalarda 0,14, portakallı kolalarda 0,53, meyve aromalı sodalarda 0,88, enerji içeceklerinde 0,47, meyve sularında 1,46 ve süt ürünlerinde 0,25 olarak bulundu. Bütün numunelerin etanol seviyesi kodekste izin verilen sınırın altında bulundu.
- MakaleAçık Erişim2017A new colorimetric DPPH• scavenging activity method with no need for a spectrophotometer applied on synthetic and natural antioxidants and medicinal herbs
Akar, Zeynep; Küçük, Murat; Doğan, Hacer
2,2-Diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging, the most commonly used antioxidant method with more than seventeen thousand articles cited, is very practical; however, as with most assays, it has the major disadvantage of dependence on a spectrophotometer. To overcome this drawback, the colorimetric determination of the antioxidant activity using a scanner and freely available Image J software was developed. In this new method, the mixtures of solutions of DPPH• and standard antioxidants or extracts of common medicinal herbs were dropped onto TLC plates, after an incubation period. The spot images were evaluated with Image J software to determine CSC50 values, the sample concentrations providing 50% colour reduction, which were very similar with the SC50 values obtained with spectrophotometric method. The advantages of the new method are the use of lower amounts of reagents and solvents, no need for costly spectrophotometers, and thus significantly lowered costs, and convenient implementation in any environment and situation.
- MakaleYalnız künye2017An on-line HPLC system for detection of antioxidant compounds in some plant extracts by comparing three different methods
Arslan Burnaz, Nesibe; Küçük, Murat; Akar, Zeynep
Echinacea (Echinacea purpurea), green tea (Camellia sinensis) and yaylacayi (Thymus praecox OPIZ subsp. grossheimii (Ronniger) Jalas) are herbs used in traditional medicine because of their beneficial health effects. A high performance liquid chromatography (HPLC) post-column method was developed by coupling HPLC with on-line antioxidant assays using diode array (DAD) and ultraviolet (UV) detectors. Thus antioxidant compounds and fifteen phenolic standards were detected in echinacea, green tea and yaylacayi methanol extracts simultaneously. Later on, the developed on-line HPLC coupled system was used to compare three different antioxidant methods, ABTS [2,2′-Azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)], DPPH (2,2-diphenyl-1-picrylhydrazyl and FRAP (Ferric reducing antioxidant power). Eight compounds with antioxidant activity were identified as gallic acid, protocatechuic aldehyde, p-OH benzoic acid, chlorogenic acid, caffeic acid, vanillin, ferulic acid, and rosmarinic acid. For validation purposes, LOD (limit of detection) (0.36–14.68 μg/mL) and LOQ (limit of quantification) (1.35–48.92 μg/mL) values were calculated for six standards. The results showed that while the post-column ABTS and FRAP assays were repeatable, sensitive and supportive of each other, the post-column DPPH assay did not provide reliable results. Also due to the base-line noise and drifts in post-column DPPH assay, identification and quantitation of analytes could not be done accurately.
- MakaleAçık Erişim2016Synthesis of new 1,2,4-triazole compounds containing Schiff and Mannich bases (morpholine) with antioxidant and antimicrobial activities
Ünver, Yasemin; Deniz, Sadik; Çelik, Fatih; Akar, Zeynep; Küçük, Murat; Sancak, Kemal
Compound 2 was synthesized by reacting CS2/KOH with compound 1. The treatment of compound 2 with hydrazine hydrate produced compound 3. Then, compound 3 was converted to Schiff bases (4a–d) by the handling with several aromatic aldehydes. The treatment of triazole compounds 4a–d containing Schiff base with morpholine gave compounds 5a–d. All compounds were tested for their antioxidant and antimicrobial activities. The antioxidant test results of DPPH• radical scavenging and ferric reducing/antioxidant power methods showed good antioxidant activity. The triazole-thiol (3) was the most active, and the effect of the substituent type of the thiophene ring on the activity was same for both Schiff bases (4a–d) and Mannich bases (5a–d). Among the newly synthesized triazole derivatives, the Schiff base 4d and the Mannich base 5d carrying nitro substituent on the thiophene ring showed promising antibacterial and antifungal activity, with lower MIC values than the standard antibacterial ampicillin.
- MakaleAçık Erişim2016Antioxidant, antiradical, and anticholinergic properties of cynarin purified from the Illyrian thistle (Onopordum illyricum L.)
Topal, Meryem; Gocer, Hulya; Topal, Fevzi; Kalin, Pinar; Köse, Leyla Polat; Gulçin, Ilhami; Çakmak, Kader C.; Küçük, Murat; Durmaz, Lokman; Gören, Ahmet C.
Cynarin is a derivative of hydroxycinnamic acid and it has biologically active functional groups constituent of some plants and food. We elucidated the antioxidant activity of cynarin by using different in vitro condition bioanalytical antioxidant assays like DMPD•+, ABTS•+, DPPH• and H2O2 scavenging effects, the total antioxidant influence, reducing capabilities, Fe2+ chelating and anticholinergic activities. Cynarin demonstrated 87.72% inhibition of linoleic acid lipid peroxidation at 30 g/mL concentration. Conversely, some standard antioxidants like trolox, tocopherol, butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA) exhibited inhibitions of 90.32, 75.26, 97.61, 87.30%, and opponent peroxidation of linoleic acid emulsion at the identical concentration, seriatim. Also, cynarin exhibited effective DMPD•+, ABTS•+, DPPH•, and H2O2 scavenging effects, reducing capabilities and Fe2+ chelating effects. On the contrary, IC50 and Ki parameters of cynarin for acetylcholinesterase enzyme inhibition were determined as 243.67 nM (r2: 0.9444) and 39.34 ± 13.88 nM, respectively. This study clearly showed that cynarin had marked antioxidant, anticholinergic, reducing ability, radical-scavenging, and metal-binding activities.
- MakaleAçık Erişim2016Acetylcholinesterase and carbonic anhydrase isoenzymes I and II inhibition profiles of taxifolin
Gocer, Hulya; Topal, Fevzi; Topal, Meryem; Küçük, Murat; Teke, Dilek; Gülçin, Ilhami; Alwasel, Saleh H.; Supuran, Claudiu T.
Taxifolin, also known as dihydroquercetin, is a flavonoid commonly found in plants. Carbonic anhydrase (CA, EC 4.2.1.1) plays an important role in many critical physiological events including carbon dioxide (CO2)/bicarbonate (HCO3-) respiration and pH regulation. There are 16 known CA isoforms in humans, of which human hCA isoenzymes I and II (hCA I and II) are ubiquitous cytosolic isoforms. In this study, the inhibition properties of taxifolin against the slow cytosolic isoenzyme hCA I, and the ubiquitous and dominant rapid cytosolic isoenzyme hCA II were studied. Taxifolin, as a naturally bioactive flavonoid, has a K-i of 29.2nM against hCA I, and 24.2nM against hCA II. For acetylcholinesterase enzyme (AChE) inhibition, K-i parameter of taxifolin was determined to be 16.7nM. These results clearly show that taxifolin inhibited both CA isoenzymes and AChE at the nM levels.
- MakaleAçık Erişim2015Synthesis and biological evaluation of a new series of 4-alkoxy-2-arylquinoline derivatives as potential antituberculosis agents
Tosun, Gonca; Arslan, Tayfun; Iskefiyeli, Zeynep; Küçük, Murat; Karaoʇlu, Şengül Alpay; Yayli, Nurettin
Three new series of 33 quinolone compounds, 2-(2-, 3-, and 4-fluorophenyl)-4-O-alkyl(C5-15)quinolines (7a-k, 8a-k, and 9a-k), were synthesized from 2-(2-, 3-, and 4-fluorophenyl)-2,3-dihydroquinolin-4(1H )-one (4, 5, and 6) by the reaction of alkyl halides under basic conditions in DMF. The new compounds 7a-k, 8a-k, and 9a-k were synthesized from flavonones 4-6, which can be considered new precursors for quinoline synthesis through a one-step reaction. All the target compounds (7a-k, 8a-k, and 9a-k) were evaluated for their in vitro antimicrobial activity against nine test microorganisms. They showed the most activity against Mycobacterium smegmatis with minimum inhibitory concentrations (MIC) of 62.5-500 μg/mL, indicating their potential uses as antituberculosis agents. Among them 8a-k (m-fluoride) were the most active compounds against M. smegmatis (MIC, 62.5-125 μg/mL). The newly synthesized title compounds were also evaluated for their in vitro antioxidant activities using DPPH• radical scavenging and FRAP tests. They showed at a low concentration (mg/mL) a range of SC50 values of 0.03-12.48 mg/mL (DPPH•) and 0-722 μM (FRAP), respectively. The antioxidant results of compounds 7a-k, 8a-k, and 9a-k revealed that the length of the alkyl chain was negatively correlated with antioxidant capacity.
- MakaleAçık Erişim2015Antioxidant components of Viburnum opulus L. determined by on-line HPLC-UV-ABTS radical scavenging and LC-UV-ESI-MS methods
Karaçelik, Ayca Aktas; Küçük, Murat; Iskefiyeli, Zeynep; Aydemir, Sezgin; De Smet, Seppe; Miserez, Bram; Sandra, Patrick
Antioxidant activity of the juice and seed and skin extracts prepared with methanol, acetonitrile, and water of Viburnum opulus L. grown in Eastern Black Sea Region were studied with an on-line HPLC-ABTS method and off-line antioxidant methods, among which a linear positive correlation was observed. The fruit extracts were analysed with the HPLC-UV method optimised with 14 standard phenolics. Identification of the phenolic components in the juice was made using an HPLC-UV-ESI-MS method. Nineteen phenolic compounds in juice were identified by comparing the retention times and mass spectra with those of the standards and the phenolics reported in the literature. The major peaks in the juice belonged to coumaroyl-quinic acid, chlorogenic acid, procyanidin B2, and procyanidin trimer. Quite different antioxidant composition profiles were obtained from the extracts with the solvents of different polarities. The antioxidant activities of the seed extracts were higher than those of the skin extracts in general. (C) 2014 Elsevier Ltd. All rights reserved.
- MakaleYalnız künye2014New thiophene-1,2,4-triazole-5(3)-ones: Highly bioactive thiosemicarbazides, structures of Schiff bases and triazole-thiols
Ünver, Yasemin; Sancak, Kemal; Çelik, Fatih; Birinci, Emrah; Küçük, Murat; Soylu, Serkan; Burnaz, Nesibe Arslan
Key compound 2-(4-amino-5-oxo-3-(thiophene-2-ylmethyl)-4,5-dihydro-1,2,4- tiazole-1-yl) acetohydrazide (3) was synthesized by reacting hydrazine hydrate with ethyl-2-(4-amino-5-oxo-3-(thiophene-2-ylmethyl)-4,5-dihydro-1,2,4-tiazole- 1yl)acetate (2), obtained in basic media from 4-amino-5-(thiophene-2-ylmethyl)- 2H-1,2,4-triazole-3(4H)-one (1). Compound 3 was converted to thiosemicarbazide derivatives (4a-d) and Schiff base derivatives 6a-e and 7a-e. The treatment of compound 4 with NaOH gave 4-amino-2-((4-(4-aryl)-5-mercapto-4H-1,2,4-triazole-3- yl)methyl)-5-(thiophene-2-ylmethyl)-2H-1,2,4-triazole-3(4H)-ones (5a-d). All newly compounds, well characterized by elemental analyses, IR, 1H NMR, 13C NMR and mass spectral studies were tested for their antioxidant and antimicrobial activities. Thiosemicarbazide derivatives (4a-d) were highly active in two antioxidant tests with 69.0-88.2% DPPH scavenging and 503-1257 μM TEAC values, while the others showed lower or no activity. The results of the two antioxidant tests correlated well. Moreover, Thiosemicarbazide derivatives (4a-d) also showed antibacterial activity against Staphylococcus aureus, Bacillus cereus, and Mycobacterium smegmatis. Thiosemicarbazide group deserves attention in the synthesis of bioactive compounds.