Electrical and morphological characterization of polyaniline/sulfonated poly(arylene ether sulfone) composite films

Electrically conductive polyaniline/sulfonated poly(arylene ether sulfone) (PANI/BPS-35) composites were prepared. The influence of humidity and temperature on electrical conductivity of 20 wt% polyaniline containing composite films was tested. The conductivity increment from 17 mS/cm to 44 mS/cm was observed when the temperature increased from 24 °C to 80 °C at 50% relative humidity (RH). The maximum conductivity was 53 mS/cm at 80 °C and 70% RH. Aluminum (Al) and gold (Au) contacts were deposited onto PANI/BPS composite films and their contact properties have been investigated. While Al contacts behave like Schottky type contact, Au contacts showed nearly ohmic characterization. Scanning electron microscopy technology was used to investigate the morphology of PANI/BPS-35 composite films.     

Bioaccumulation and biosorption of copper(II) and chromium(III) from aqueous solutions by Pichia stipitis yeast

BACKGROUND: Bioaccumulation and biosorption by Pichia stipitis yeast has not yet been explored. This paper evaluates, for the first time, the use of both viable and nonviable P. stipitis yeast to eliminate Cu(II) and Cr(III) from aqueous solutions. The effect of Cu(II) and Cr(III) ions on the growth and bioaccumulation properties of adapted and nonadapted biomass is investigated as a function of initial metal concentration. Binding capacity experiments using nonviable biomass are also performed as a function of temperature. RESULTS: The addition of Cu(II) and Cr(III) had a significant negative effect on the growth of yeast. Nonadapted cells could tolerate Cu(II) and Cr(III) ions up to a concentration of 75 ppm. The growth rate of nonadapted and adapted cells decreased with the increase in Cu(II) and Cr(III) concentration. Adapted P. stipitis biomass was capable of removing Cu(II) and Cr(III) with a maximum specific uptake capacity of 15.85 and 9.10 mg g⁻¹, respectively, at 100 ppm initial Cu(II) and Cr(III) concentration at pH 4.5. Adsorption data on nonviable cells were found to be well modeled by the Langmuir and Temkin isotherms. The maximum loading capacity of dry biomass predicted from Langmuir isotherm for Cu(II) and Cr(III) at 20 °C were 16.89 and 19.2 mg g⁻¹, respectively, at pH 4.5. Biosorptive capacities were dependent on temperature for Cu(II) and Cr(III) solutions. CONCLUSION: Cu(II)‐ and Cr(III)‐adapted cells grow and accumulate these ions at high ratios. On the other hand, nonviable P. stipitis was found to be an effective biosorbent for Cu(II) and Cr(III) biosorption. Copyright © 2008 Society of Chemical Industry     

Bioactivities of essential oil and extract of Thymus argaeus,Turkish endemic wild thyme

BACKGROUND: Thymus argaeus Boiss. & Bal. (Lamiaceae), an endemic plant species of Turkey known as wild thyme, is traditionally used as a spice and a wild tea in the Inner Anatolia region of Turkey. In this study the composition of the essential oil and the antimicrobial and antioxidant effects of the methanolic extract and essential oil of T. argaeus were determined. RESULTS: The main components of the essential oil were linalool (499 g kg^?1), α‐terpineol (150 g kg^?1), linalyl acetate (97 g kg^?1) and thymol (94 g kg^?1). The total phenolic, flavanol and flavonol contents of the extract were 83.31 ± 0.59 mg gallic acid equivalent g^?1, 6.26 ± 0.00 mg catechin equivalent g^?1 and 28.81 ± 0.21 mg rutin equivalent g^?1 respectively. The antioxidant activities of the extract and essential oil determined by the 2,2‐diphenyl‐1‐picrylhydrazyl radical‐scavenging method were 830.18 ± 0.42 and 20.47 ± 2.3 mg g^?1 respectively. The antimicrobial activities of the extract and essential oil against 13 bacteria and two yeasts were studied by the agar diffusion method. The micro‐organisms most sensitive to the essential oil were Aeromonas hydrophila and Pseudomonas aeruginosa, while the micro‐organism most sensitive to the extract was P. aeruginosa. CONCLUSION: Only the extract of T. argaeus could be used as a natural antioxidant, while both the extract and the essential oil could be useful as natural antimicrobial agents in food preservation. Copyright © 2009 Society of Chemical Industry     

Quality characteristics of doner kebab made from sucuk dough which is a dry fermented Turkish sausage

The objective of this study was to determine certain quality characteristics of the raw and cooked doner kebabs made from beef and sucuk dough which is a traditional fermented sausage. The doners were divided into two groups; traditional beef doners and sucuk dough groups, and all the samples were frozen and stored at (−30 ±1 °C) for 60 days to monitor their quality characteristics. All of the raw and cooked doner samples were subjected to chemical and microbiological analysis while only the cooked doners were evaluated organoleptically at 0th, 30th and 60th days of storage. In the chemical analysis; proximate composition (% moisture, % protein, % fat, and % ash), pH and TBA values were determined. The samples were examined for total aerobic plate count (APC), total anaerobes, psychrotrophic bacteria, total coliforms, total staphylococcus/micrococcus count, mould and yeast to observe the hygienic quality of the doner samples. The results of chemical analysis, in general, showed that sucuk doners had higher ash content, pH and TBA values, and all of the doners had higher APC, psychrotrophic bacteria and coliform counts at the beginning compared to 30th and 60th days of storage not only in the raw condition but also in cooked counterparts. The sensory evaluation results indicated that sucuk doners received favorable preferences, therefore, traditional sausage (sucuk) dough application in doner production could be possible without posing any acceptability problems in terms of quality factors compared to traditional beef doners.     

Comparison of the Effects of Statins on A549 Nonsmall-Cell Lung Cancer Cell Line Lipids Using Fourier Transform Infrared Spectroscopy: Rosuvastatin Stands Out

Statins are commonly prescribed antilipidemic and anticholesterol class of drugs. In addition to their major role, they have been found to have anticancer effects on in vitro, animal and clinical studies. The aim of this study was to investigate the effects of six different statins (rosuvastatin, pravastatin, simvastatin, lovastatin, fluvastatin, and atorvastatin) on A549 cancer cells lipids by Fourier transform infrared (FTIR) spectroscopy. Proliferation tests were carried out to detect the half-maximal inhibitory concentrations (IC₅₀) of each statin on A549 cells. The IC₅₀ values were 50 μM for simvastatin, 150 μM for atorvastatin and pravastatin, and 170 μM for fluvastatin, 200 μM for rosuvastatin and lovastatin on A549 cells. No correlation was found between the antiproliferative effects of the statins and lipid-lowering effect. The cells were treated with IC₅, IC₁₀, and IC₅₀ values of each statins concentration and lipid extracts were compared using FTIR spectroscopy. The results indicated that different statins had different effects on the lipid content of A549 cells. The FTIR spectra of the lipid exctracts of statin-treated A549 cells indicated that the value of hydrocarbon chain length, unsaturation index, oxidative stress level, and phospholipid containing lipids increased except for rosuvastatin-treated A549 cells. In addition, rosuvastatin significantly lowered cholesterol ester levels. In conclusion, the contrasting effects of rosuvastatin should be further investigated.     

Improvement of dewatering capacity of a petrochemical sludge

Oily sludge produced from a petrochemical industry was used to investigate the improvement of its dewatering properties. The oil content (OC) and the dry solid content (DS) of the raw sludge were respectively, 15% and 3.6% by weight. The capillary suction time (CST) and the specific resistance to filtration (SRF) of the raw petrochemical industrial sludge were found to be 2000s and approximately 5.5x10(16)m/kg, respectively. Conventional chemical conditioners such as alum, lime, and polyelectrolyte, and less conventional ones like fly ash, gypsum, and bentonite were used in the sludge conditioning studies. Conventional chemical conditioners gave better results for the enhancement of the dewatering capacity of the sludge. The best result was obtained by using 0.9% cationic polyelectrolyte by weight, and a decrease of 99%-95% were achieved for CST and SRF, respectively, when this dosage of cationic polyelectrolyte was used.     

The Use of Boron Compounds for Stabilization of Lipase from Pseudomonas aeruginosa ES3 for the Detergent Industry

This study aimed to characterize a lipase that is highly active and stable under typical washing conditions for use as a detergent ingredient by investigating the effects of various boron compounds on lipase stabilization under different conditions. In addition, the antimicrobial activity of the boron compounds used in enzyme stabilization was examined in order to obtain an effective antimicrobial detergent. A lipase‐producing bacterium was isolated from kitchen wastewater samples using Rhodamine‐B Agar medium and identified as Pseudomonas aeruginosa based on 16S rDNA sequence analysis. The ES3 lipase obtained from P. aeruginosa was purified, and the purified enzyme was found to have a molecular mass of 40 kDa. The enzyme showed optimal activity at pH 9.0–10.0 and 40 °C and remained stable in the presence of various metal ions, surfactants and oxidizing agents. Moreover, the pH stability and thermostability of the enzyme was improved by the addition of boron compounds, which, when used as stabilizers in the incubation media, also increased the stability of the enzyme towards commercial detergents. Furthermore, the enzyme displayed properties comparable with the commercial product Lipolase^®, which has shown excellent stability towards various commercial detergents. Finally, boron compounds used to stabilize the lipase were found to possess antimicrobial properties, suggesting that detergents incorporating these compounds will also exhibit antimicrobial activity when washing clothes and dishes.     

Effect of grape pomace extracts obtained from different grape varieties on microbial quality of beef patty

Grape pomace extracts were obtained from 5 different grape varieties grown in Turkey. The extracts were concentrated to obtain crude extracts; and incorporated into beef patties at 0% (Control), 1%, 2%, 5%, and 10% concentrations to test their antimicrobial effects in different storage periods (first, 12, 24, and 48 h). The numbers of microorganism were generally decreased by the extract concentration during the storage period. All the microorganisms tested were inhibited by the extract concentration of 10% in all the storage periods. Furthermore, the foodborne pathogens including Enterobacteriaceae and coliform bacteria, and the spoilage microorganisms including yeasts and moulds and lipolytic bacteria were also inhibited by 5% of Emir, Gamay, and Kalecik Karasi varieties in beef patties. Considering the results, the extracts of grape pomaces might be a good choice in the microbial shelf life extension of the food products as well as inhibiting the food pathogens as the case of beef patties. PRACTICAL APPLICATION: Grape pomace consists of seeds, skins, and stems, and an important by-product that is well known to be the rich source of phenolic compounds, both flavonoids and non-flavonoids. These substances have considerable beneficial effects on human health. The use of natural antimicrobial compounds, like plant extracts of herbs and spices for the preservation of foods has been very popular issue because of their antimicrobial activity. Therefore, grape pomace should be added into some food formulations to benefit from their protective effects. In this respect, this study reports the effect of addition of grape pomace extracts obtained from different grape varieties on microbial quality of beef patty. The results obtained in this study may be useful for food industry, which has recently tended to use natural antimicrobial sources in place of synthetic preservatives to prevent microbial spoilage.     

Antioxidative, antiradikale und antimikrobielle Aktivitäten des Fruchthüllen-Extrakts von frischen Antep-Pistazien

Pistacia vera L. is the only genus of more than ten in Pistacia species consumed as a nut and has commercial value. Turkey is one of the homelands of the pistachio species, and they are named Antep pistachio. When Antep pistachios are processed into nuts, their reddish purple hulls are removed as a waste after the processing. In this research, Antep pistachio hull samples extracted by methanol, ethanol and water were tested for antioxidant and antiradical (IC₅₀ value) potentials, and antimicrobial activities as well. The values of total phenolic content of methanol extracts of Antep pistachio hull was 167.49 ± 0.48 mg gallic acid equivalent (GAE)/g dry extract. The ethanol and aqueous extract of the pistachio hulls were determined as 89.87 ± 0.44 and 31.73 ± 0.21 mg GAE/g dry extract, respectively. The antioxidant activities of extracts were evaluated by the phosphomolybdenum method. The highest antioxidant activity of the hull extracts was determined in the methanol extracted samples (152.10 ± 0.19 mg ascorbic acid equivalent (AAE)/g dry extract), while the lowest value was in the ethanol extracts (15.19 ± 0.00 mg AAE/g dry extract). The values of IC₅₀ in methanol, ethanol and aqueous extracts of the pistachio hulls were 16.01, 21.62 and 24.45 μg/ml, respectively. The highest antiradical activity was in the methanol extract of Antep pistachio hulls. In this research, the pistachio hull extracts were tested for antimicrobial activities against total 15 microorganisms, 13 bacteria and 2 yeasts. The aqueous extract of the hull was the most ineffective extract against the microorganisms tested. The methanol and ethanol extracts of the pistachio hulls, which had limited antimicrobial effect against the bacteria, Mycobacterium smegmatis, Salmonella typhimurium, Proteus mirabilis and Yersinia enterocolitica, and the yeasts, Saccharomyces cerevisiae and Candida albicans, and were effective on the other microorganisms constituted inhibition zones diameter as between 10 and 39 mm. All extracts of the pistachio hulls exhibited antimicrobial activity against Listeria monocytogenes (6–38 mm) and Escherichia coli O157: H7 (8–28 mm). In conclusion, the hulls of Antep pistachio can be evaluated as a potential antimicrobial and antioxidant resource in the food systems.     

Determination of the quality and purity characteristics of olive oils obtained from different regions of Turkey,depending on climatic changes

Virgin olive oils (VOOs) obtained from olives grown in different regions of Turkey under changing climatic conditions sometimes show different sensory and chemical properties. This study was planned to determine whether these deviations are due to climatic changes or not. For this purpose, five different olive varieties (Ayvalık, Memecik, Gemlik, Nizip Yağlık, Kilis Yağlık) of commercial importance were harvested from the provinces/districts (four different region) where cultivation is intense during the 2017/2018–2020/2021 harvest years. Every year, olive samples were collected from 3 orchards from 13 provinces/districts. One hundred and fifty-six samples were subjected to the purity, quality and sensory analysis. Basic climatic values (average, minimum and maximum temperature, humidity and precipitation) were examined for four consecutive years. All of the examined olive oil samples were determined within the legal limits in terms of fatty acid composition and fatty acid ethyl ester values. However, delta-7-stigmastenol value from the sterol composition was found to be above 0.5% in some samples in all the years studied (total 21 samples). Delta-7-stigmastenol values of olive oil samples varied between 0.16% and 1.14%. Multiple linear regression analysis was applied using a genetic algorithm-based inverse least squares method to determine whether there is a relationship between climate data and delta-7-stigmastenol values. According to this result, it has been determined that the delta-7-stigmastenol value is high when the annual average relative humidity is low and the annual average temperature is high. There is an urgent need to make forward-looking plans due to climate change.