Effect of ultraviolet and far infrared radiation on microbial decontamination and quality of cumin seeds

Abstract: Cumin seeds might be exposed to a high level of natural bacterial contamination, and this could potentially create a public health risk besides leading to problems in exportation. Ultraviolet (UVC) and far infrared (FIR) radiation has low penetration power, and due to that, there might be no detrimental defects to the products during a possible decontamination process. Therefore, the objective of this study was to determine the effect of UVC and FIR treatment on microbial decontamination and quality of cumin seeds. For this purpose, FIR treatment at different exposure times and temperatures were applied followed by constant UVC treatment with an intensity of 10.5 mW/cm² for 2 h. Total mesophilic aerobic bacteria of the cumin seeds were decreased to the target level of 10⁴ CFU/g after 1.57, 2.8, and 4.8 min FIR treatment at 300, 250, and 200 °C, respectively, following a 2 h UVC treatment. Under the given conditions, a complete elimination for total yeast and molds were obtained while there were no significant changes in volatile oil content and color of the cumin seeds. Consequently, combined UVC and FIR treatment was determined to be a promising method for decontamination of the cumin seeds. Practical Application: This research attempts to apply UVC and far infrared (FIR) radiation for pasteurization of cumin seeds. The data suggested that combined UVC and FIR radiation treatments can become a promising new method for pasteurization of cumin seeds without causing any detrimental defect to the quality parameters. The results of this industry partnered (Kadioglu Baharat, Mersin, Turkey— http://www.kadioglubaharat.com ) study were already applied in industrial scale production lines.     

Micelle-Mediated Extraction and Flame Atomic Absorption Spectrometric Method for Determination of Trace Cobalt Ions in Beverage Samples

A new method has been developed for preconcentration of cobalt at trace levels in beverage samples using calcon carboxylic acid as chelating agent and cetyl pyridinium chloride as an auxiliary ligand and entrapped into Triton X-114 prior to its determination by flame atomic absorption spectrometry (FAAS). The main parameters affecting cloud point extraction (CPE) efficiency such as pH, concentration of the complexing agent, cationic and nonionic surfactant concentration, salt effect, the equilibrium time, and temperature were investigated and optimized. After optimization of the CPE conditions, a preconcentration factor of 60, an enhancement factor of 106, and a detection limit of 0.20 μg L⁻¹ by (R ² = 0.9978) were obtained from a calibration curve constructed in the range of 0.7–100 μg L⁻¹. The proposed preconcentration procedure was successfully applied to the determination of cobalt ions in some real samples including natural drinking water, tap water, and beer and wine samples. The accuracy and validity of the proposed CPE/FAAS method was tested by means of five repeated analysis of reference standard materials (TM-253, a low level fortified water standard for trace elements). A good agreement between analytical results (28.8 and 28.5 μg L⁻¹ with calibration curve and standard addition curve method, respectively) and certified value (27.9 μg L⁻¹) for Co (p < 0.05) were obtained and verified by means of calibration curve and standard addition curve method using CPE procedure.     

Molecular characterization of mulberry (Morus spp.) genotypes via RAPD and ISSR

BACKGROUND: In recent years, DNA‐based markers have been used quite extensively because of their many advantages over the traditional morphological and biochemical markers. Many studies have shown that molecular markers are useful in delineating the genetic relationships among closely related mulberry genotypes and cultivars. Thus, in the present study, polymer chain reaction based DNA fingerprinting techniques were used to investigate the genetic relationships among mulberry genotypes growing in different agro‐climatic regions of Turkey. RESULTS: 20 RAPD primers generated a total of 173 bands, of which 157 (90.75%) were polymorphic. As for 11 ISSR primers, 124 bands (96.55%) were polymorphic in a total of 128. The similarity index for RAPD technique ranged between 0.24–0.98; 25?s203 with 25?s112 were found to be the closest genotypes, while 24Ke10 and 25?s123 were the most distant ones. According to the ISSR result, the genetic similarity index changed between 0.21–095; 25?s203 with 25?s112 genotypes were the closest, while 25?s08 and 01KaD2 were the most distant ones. CONCLUSION: The RAPD and ISSR markers were found to be promising for assessing genetic diversity in mulberry genotypes. Copyright © 2011 Society of Chemical Industry     

The effects of rosemary extract combination with vacuum packing on the quality changes of Atlantic mackerel fish burgers

The effects of the use of antioxidant technology on the quality of mackerel burgers stored at 4 °C were investigated in terms of sensory, biochemical [thiobarbituric acid (TBA), total volatile basic nitrogen (TVB‐N), peroxide value (PV) and free fatty acids (FFA)] and microbiological analyses [total viable count (TVC)]. Fish meat was divided into three groups; the control (C) without rosemary extract, the second group with 0.4% rosemary extracts (Group A) and the third with 0.8% rosemary extracts (Group B). Results showed that the TVB‐N level did not exceed acceptability limit (30–35 mg 100 g^?1) for all groups. TBA value for the control significantly increased from 1.47 to 4.80 MA kg^?1 whereas it slightly increased in treatment groups as the storage time increased. Significantly higher PV and FFA (P < 0.05) were obtained from the control group. Rosemary extract, in combination with vacuum pack was effective in controlling the growth of bacteria and biochemical indices.     

Towards more active and stable PdAgCr electrocatalysts for formic acid electrooxidation: The role of optimization via response surface methodology

In this study, multiwall carbon nanotube (MCNT)‐supported Pd (Pd/MWCNT) catalysts are prepared by using NaBH₄ reduction method. In order to maximize the oxidation and reduction of H₂SO₄, synthesis conditions (Pd ratio, molar ratio of NaBH₄/K₂PdCl₄, volume of deionized water, and duration of agitation) are optimized by using response surface methodology (RSM). The optimum synthesis conditions are determined as 58.2% of Pd by weight, 154.6 molar ratio of NaBH₄ to K₂PdCl₄, 19.48 mL of deionized water, and 186.16 min of agitation duration. The effect of electrochemical measurement conditions on the oxidation kinetics of Pd/MWCNT is also investigated by RSM. The optimum electrochemical measurement conditions are found as 10 μL of catalyst mixture, 90°C of H₂SO₄ solution, and 5.5 M H₂SO₄. The Pd/MWCNT, Pd₅₀Ag₅₀/MWCNT, and Pd_65.6Ag_33.6Cr_0.80/MWCNT catalysts prepared under optimized conditions are characterized by using X‐ray diffraction, transmission electron microscopy, N₂ adsorption‐desorption, and inductively coupled plasma mass spectrometry. The crystallite sizes of these catalysts are found as 4.85, 5.66, and 5.26 nm for Pd/MWCNT, Pd₅₀Ag₅₀/MWCNT, and Pd_65.6Ag_33.6Cr_0.80/MWCNT catalysts, respectively. Isotherms of all these catalysts are found to be similar to Type V isotherms with H3 hysteresis loop. The average particle size of Pd₅₀Ag₅₀/MWCNT and Pd_65.6Ag_33.6Cr_0.80/MWCNT catalysts are determined as 5.2 and 9.2 nm, respectively. Electrochemical performance of as‐prepared catalysts is evaluated by using cyclic voltammetry and chronoamperometry. The formic acid electrooxidation (FAEO) activities are found as 18.9, 27.8, and 51.6 mA/cm² for Pd/MWCNT, Pd₅₀Ag₅₀/MWCNT, and Pd_65.6Ag_33.6Cr_0.80/MWCNT, respectively. Pd_65.6Ag_33.6Cr_0.80/MWCNT shows the highest activity and stability. Optimization of synthesis conditions and electrochemical measurement parameters allow us to obtain very good electrochemical activity and stability for FAEO reaction compared with anode catalysts in the literature.     

Concentrations of elements in Lias coals from the eastern Black Sea Region,NE-Turkey

The element contents and organic matter-element relation between Lias-aged coals exposed in four fields in Gümü?hane and Bayburt were investigated. In general, fixed carbon and gross calorific values of the Edire and Balkaynak coals are higher than Güvercinlik and Çerçi coals. The highest ash yields were observed in the Çerçi coals. The concentrations of Mg, P, Ca, Mo, Y, Ni, U, Zn, Ga, Ba, W, Sr, Ta, and Be of the analysed coals are positively correlated with ash yield, indicating an organic affinity. The Lias-aged coals located in Gümü?hane and Bayburt are low-rank coals.     

Synthesis and characterization of phosphorus-containing methacrylate-based difunctional crosslinkers and their use in UV-curable resin systems

Two new phosphorus-containing methacrylate-based difunctional crosslinking agents [bis(4-(2-methacryloyloxy)ethyl carboxyl)phenyl phosphine oxide (BEPPPO) and bis(4-(2-methacryloyloxy)ethylcarbonylaminophenyl)phenyl phosphine oxide (BUPPPO)], which can be good candidates for UV-curable coating applications, were synthesized by reacting either a phosphorus-containing diisocyanate [bis(4-isocyanatophenyl)phenyl phosphine oxide] or a phosphorus-containing diacid chloride [bis(4-chloroformylphenyl)phenyl phosphine oxide] with hydroxyethyl methacrylate. The structures of the monomers thus obtained were characterized by FTIR, mass, and ¹H-NMR spectroscopies. The contents of the new crosslinking agents in the UV-cured polymeric films were varied between 10 and 30% by weight. Mechanical, physical, and thermal characterizations of the UV-cured films were investigated. An increase in crosslinking agent content caused an increse in mechanical properties. Films containing BUPPPO had higher tensile strength values compared to the films containing BEPPPO. Thermogravimetric analysis of phosphorus-containing crosslinking agents revealed that incorporating phosphorus into the structure resulted in a high char yield up to 24.5% at 600°C. Water absorption values of UV-cured films were also affected by the amount and type of crosslinking agent. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2575–2585, 1999     

Anaerobic digestion of Aegean olive mill effluents with and without pretreatment

BACKGROUND: Olive oil production is an important economical activity in the Aegean region of Turkey. However, the effluents of the olive oil producing mills with their high organic loads and toxic compounds are causing serious environmental problems. The anaerobic biological treatment of olive mill wastewater (OMWW) using the treatment plants of the regional industries could be a method of choice and within the scope of this study floccular and granular sludges were investigated in batch mode for their success in the treatment of OMWW while producing biogas. The major limitation of this treatment is the inhibition of methanogenic bacteria by the phenolic compounds in OMWW. Thus an integrated solution was suggested in which a pre‐treatment step (dephenolization) was also introduced before biological step. RESULTS: The effluents of 27 olive mills out of 47 were found to have total phenolics (TP) less than 3 g L^?1 and could be treated anaerobically after simple dilution. The biogas production for the untreated OMWW was higher for floccular sludge than for the granular sludge (68.5 mL and 45.7 mL respectively). Combined pre‐treatment experiments, first coagulation with polyaluminum chloride, followed by flocculation with cationic polyelectrolyte and finally Fenton's oxidation, could remove 80% of TP and 95% of the total suspended solids. CONCLUSION: OMWW having TP values less than 3 g L^?1 can be treated anaerobically using floccular sludge after simple dilution and biogas can be produced. For OMWW samples having higher TP values pre‐treatment is necessary and the pre‐treatment given in this study may be used effectively. Copyright © 2010 Society of Chemical Industry     

Influence of pH on recombinant human growth hormone production by Pichia pastoris

BACKGROUND: Effect of pH on recombinant human growth hormone (rhGH) production by Pichia pastoris hGH‐Mut⁺ was investigated at pH = 4.2, 5.0, 5.5, and 6.0. RESULTS: The highest cell concentration was obtained at pH = 6.0 with 53 g L^?1, while the highest rhGH concentration was attained at pH = 5.0 as 0.27 g L^?1. Total protease secretion increased with increase in pH and with the cultivation time. Oxygen uptake rate increased with increasing pH up to pH = 6.0, having the maximum value, 37 mmol m^?3 s^?1, at pH = 5.5. K_La values were similar at all the conditions, having a maximum value of 0.14 s^?1 at pH = 5.0. Taking the final rhGH concentration into account, the most favourable pH was 5.0; where AOX1 expression level showed a similar trend to AOX activity profiles, having the highest value of 9.4 × 10¹⁰ copy mg^?1 CDW at t = 15 h; in parallel to AOX1 expression profile, hGH expression level increased until t = 15 h, with the highest value of 4.0 × 10¹⁰ copy mg^?1 CDW, where a sharp increase in rhGH concentration was obtained. The expression levels of pep4, prb1 and prc1 genes, responsible from the production of proteinase A, proteinase B and, carboxypeptidase Y, were parallel to each other. CONCLUSION: Since it was shown that pH is a crucial operating parameter in fermentation processes using P. pastoris, keeping pH constant at its determined optimum value, pH = 5.0, during the bioprocess is vital in terms of recombinant protein production. Copyright © 2010 Society of Chemical Industry     

Effects of use of higher strength interlayer and external cooling on properties of friction stir welded AA6061-T6 joints

Although sound AA6061-T6 joints can be produced by friction stir welding, a loss in strength takes place in the weld region. In this study, it was demonstrated that the strength of the nugget could be increased by the use of a higher strength interlayer during friction stir welding. This strength recovery cannot, however, be attainable in the heat affected zone. Although an external cooling was applied during welding in order to increase strength in the heat affected zone, it was not sufficient for achieving the required cooling condition for improved strength.