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Food Safety, Fish and Listeriosis Texte intégral
2019
Alejandro De Jesús Cortés Sánchez | Martha Lorena Guzmán Robles | Rodolfo Garza Torres | Luis Daniel Espinosa Chaurand | Mayra Diaz Ramirez
Listeria monocytogenes is a food pathogen responsible for listeriosis, a relevant disease in public health worldwide. The genus Listeria spp., corresponds to cosmopolitan bacteria and capable of surviving different adverse conditions, which increases the risk for the food to be contaminated at any stage of the food chain. Fish and fish products are foods of high production level and, due to their chemical or nutritional composition, are highly susceptible to deterioration and contamination by pathogens in their productive chain relating to cases of listeriosis. Derived from the incidence and human mortality due to causative agents of listeriosis, along with their resistance to antimicrobials, they have acquired a greater emphasis on human health, animal health and food industry, resulting in the implementation of safety systems such as good hygiene practices, Hazard Analysis and Critical Control Points (HACCP) system, analytical methods and microbiological criteria, as some of the actions to contribute to the food safety and public health protection. The purpose of this review document is to provide, in a general way, aspects involved in foodborne illnesses, specifically listeriosis and its association with fish as a transmitting food, considering the prevention and control measures of this disease through food. It also includes aspects related to antimicrobial resistance by bacterial isolates obtained from fish, their implications and health risks.
Afficher plus [+] Moins [-]Antioxidant Activities of Eucheuma sp. (Rhodophyceae) and Laminaria sp. (Phaeophyceae) Texte intégral
2019
İlknur Ak | Gülen Türker
In this study, antioxidant activities of two macroalgae, Eucheuma sp. J.Agardh and Laminaria sp., J.V.Lamouroux used as food supplements were investigated. The antioxidant activity, free radical scavenging activity, the total content of phenolics, flavonoids and condensed tannins in extracts were determined. The IC50 values of the extracts of Eucheuma sp. and Laminaria sp. on DPPH scavenging activity was 2.26±0.03 mg/g and 2.63±0.03 mg/g of extract, respectively. The maximum total phenolic (5.31±0.04 mg GAE/g Ext.) were determined. According to our results, all extracts exhibited low radical scavenging activity when compared to the standards used, i.e. -tocopherol and butylated hydroxytoluene (BHT) with the inhibition percentage in the range of 48.45±0.06% (Eucheuma sp.) – 58.49±0.03% (Laminaria sp.). The highest flavonoid content was measured as 18.78±0.10 mg rutin/g of extract in Laminaria sp. The condensed tannins were not detected in Eucheuma sp. However, this value was measured as 6.24±0.60 mg CE/g of extract for Laminaria sp. According to our results, Eucheuma sp. and Laminaria sp., which are commercially sold in medicinal herb stores, are good sources of antioxidant components because of their phenolic and flavonoid contents.
Afficher plus [+] Moins [-]Effects of the Season on the Rooting Performance on the Local Olive Types of Northern Cyprus Texte intégral
2019
Nihat Yılmaz | Tijen Mahmutoğlu | Duran Özkök
In this study, rooting performance of cuttings of local olive types of Northern Cyprus taken in spring and autumn seasons was investigated. Gemlik Olive cultivar was used as the control group and 14 different local olive types constituted the experimental groups. Green cuttings taken from local olive types were initially treated with 4000 ppm indole-3-butyric (IBA) and they were then rooted in perlite medium under fogging unit in a plastic greenhouse. Following 100-days of rooting, rooting ratios, root lengths, number of roots and shooting ratios were determined. As expected, the best rooting ratio was obtained from Gemlik Olive cultivar (control group). Among the local types, the best rooting ratio (58.67%) was obtained from Çamlıköy with Type 8 olive type and the best rooting performance (45.87%) was achieved in cuttings rooted in autumn season.
Afficher plus [+] Moins [-]Effects of Different Drying Methods on Modelling, Energy Consumption and Final Quality of Tomato (Lycopersicum esculentum Mill) Texte intégral
2019
Hakan Polatcı | Yücel Erkmen
Agricultural developments mostly depend on rapidly increasing world population. Tomato is a highly nutritious vegetable. Post-harvest technologies are often applied to prolong the consumption periods of tomato. Drying is one of the oldest methods of conservation. In this study, five different drying methods (oven drying, vacuum oven drying, sensitive drying, shaded-open atmosphere drying and sun drying) was used. Drying processes were carried out with dryers at 55°C, 60°C, 65°C and 70°C temperatures. All drying trials were performed in three replications. Drying performance (drying duration, final moisture content), drying kinetics, colour analysis, energy consumption, chemical analyses were performed for all drying methods. Fresh samples reached to desired moisture contents in 20-300 hours. To define time-dependent changes in moisture contents, Page, Logarithmic and Midilli-Küçük equations were used. Page equation yielded the worst estimations. There were not significant differences in “a” redness values of fresh samples, 65-70C of oven dryer and all temperatures of sensitive dryer. Sensitive dryer yielded the closet pH values to fresh samples. Based on current findings, it was concluded that oven drying, and sensitive drying were suitable for drying Selinus tomato variety.
Afficher plus [+] Moins [-]Elements Identification in Golden Strawberries (Physalis Peruviana L.) using Wavelength Dispersive X-Ray Fluorescence Texte intégral
2019
Uğur Akbaba
Physalis peruviana (PP) is a popular exotic fruit due to its functional food properties. This product has a wide range of uses in the medical field, including treatments for cancer, malaria, hepatitis, dermatitis, rheumatism, weight loss, and diabetes. In this study, the PP element concentrations were investigated using a Wave Dispersive X-ray Fluorescence Spectrometer (WDXRF). Al, Ca, Fe, Mn, P, S, Zn, Cl, K, Mg, Na, F, Si, and B were detected, and the Ca, Fe, Zn, P, Na, Mg elements were found in significant amounts. Therefore, PP has some important health elements. For example, Mg and Mn may be associated with diabetes control. WDXRF is a cheap, quick, and non-destructive technique used in the elemental analysis of plant samples.
Afficher plus [+] Moins [-]Antimicrobial, Antioxidant Activities and Total Phenolic Contents of the Traditional Turkish Beverages Produced by Using Grapes Texte intégral
2019
Gülten Tiryaki Gündüz | Ayça Korkmaz | Ezgi Solak | Hande Didar Sözbir
In the present study, antimicrobial effects of traditional beverages produced from grapes such as traditional grape pickles, grape juice, home-made hardaliye, and commercially produced hardaliye were investigated using microdilution method against Staphylococcus aureus ATCC 6538P, Escherichia coli ATCC 25922, Salmonella Typhimurium NRRL B4420, Bacillus cereus ATCC 10876, Saccharomyces cerevisiae NRRL Y-12632, Lactobacillus acidophilus La-5 and L. rhamnosus LGG. In addition, total phenolic content was measured by the Folin-Ciocalteau method, and antioxidant activities of grape products were evaluated using DPPH assay. Results showed that grape containing beverages have antimicrobial effects on S. aureus, E. coli, S. typhimurium and B. cereus at various minimum inhibitory concentration (MIC) values in the range of 4.53-150 mg/mL. The lowest MIC value of 4.53 mg/mL was obtained against E. coli for home-made hardaliye. MIC values of the traditional grape pickles were determined as 4.69 mg/mL and 9.38 mg/mL against S.aureus and E.coli, respectively. On the other hand, traditional grape pickles showed weak inhibitory effects against B.cereus with MIC value of 150 mg/mL. The bactericidal effect of these grape products was not detected for any of the test microorganisms however traditional foods produced by using grapes were showed inhibitory effects at different concentrations against tested microorganisms except for probiotics and the yeast. The total phenolic contents of the grape products were within the range of 865.27-2193.08 mg gallic acid equivalent (GAE)/L. Free radical scavenging activities of grape samples ranged from 46% to 90% and the grape juice was found to have the highest antioxidant activity. In conclusion, grape beverages have the potential to act as a antimicrobial and antioxidant agents for use as a natural antimicrobial and antioxidant product in the food industry.
Afficher plus [+] Moins [-]Cover and Table of Contents Texte intégral
2019
Editoral Editoral
Sivas İlinde Doğal Olarak Yetişen ve Yenilebilir Bir Bitki Olan Evelik (Rumex crispus) Bitkisinin Biyoaktivitesi ve Terapotik Nitelikleri Texte intégral
2019
Sevgi Durna Daştan | Hasan Durukan | Ahmet Demirbaş | Erol Dönmez
Bitkilerden elde edilen ekstrelerin birçoğunun biyolojik etkileri ve etki mekanizmaları hakkındaki bilimsel veriler hala yetersiz olmakla birlikte bu konuya olan ilgi her geçen gün artmaktadır. Bu çalışmada, Rumex crispus (Evelik) bitkisi mevsiminde Sivas yöresinden toplanarak kurutulmuş ve sonrasında yapraklı kısımlarından etanol, metanol ve su ekstraksiyonları elde edilmiştir. Çalışmanın amacı, elde edilen her bir ekstrenin bazı mikroorganizmalar üzerindeki antimikrobiyal aktivitelerinin değerlendirilmesi, toplam antioksidan seviyesi (TAS), toplam oksidan seviyesi (TOS), oksidatif stres indeksi (OSI) değerlerinin ve çeşitli hücre hatları üzerindeki anti-kanserojen niteliklerinin ortaya konulmasıdır. TAS, TOS ve OSI değerlerini tespit etmek için Rel Assay Diagnostics kitler kullanılmıştır. Bitki ekstrelerinin mikroorganizmalara karşı minimum inhibisyon konsantrasyonunu (MIC) belirlemek amacıyla mikrodilüsyon broth yöntemi kullanılmıştır. Çalışmada antimikrobiyal aktivite analizleri, Staphylococcus aureus (ATCC 29213), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Bacillus cereus (ATCC 11778), Klebsiella pneumonia (ATCC 13883), Candida albicans (ATCC 10231) ve Candida tropicalis (DSM 11953) mikroorganizmaları kullanılarak yapılmıştır. Normal fare fibroblast hücre hattı ve 3 farklı insan kanser hücre hattında MTT yöntemi ile bitki özütlerinin sitotoksik aktivitesi belirlenmiştir. Sonuç olarak, evelik bitkisinin etanol, metanol ve su ekstraklarının denendiği mikroorganizmalar üzerinde antimikrobiyal aktivitesinin bulunmadığı, yüksek düzeyde antioksidan aktiviteye sahip olduğu ve bazı hücre kültürlerinde sitotoksik aktivitesinin olduğu tespit edilmiştir.
Afficher plus [+] Moins [-]Preparation of Glucose Sensor Based on Keggin Type Polyoxometalate/Conducting Polymer Composite for Use in Food Industry Texte intégral
2019
Yasemin Torlak | Rukiye Ayranci | Metin Ak
In continuous monitoring and control systems as required by automation, biosensors are greatly advantageous with their precision, stability, ease of use and response rates. In this study, a new amperometric glucose sensor has been fabricated based on a composite film prepared by electrochemical polymerization of carbazole derivative with having free amino group in presence of the Keggin type polyoxometalate (POM) anion, (nBu4N)3[PW9O34(tBuSiOH)3], in order to meet the needs of the sector. The enzymatic biosensor was prepared by immobilizing the Glucose Oxidase (GOx) enzyme to the surface modified with the POM/PAAC composite. Biosensor preparation and working conditions were optimized and analytical characterizations was carried out. The amperometric response of the POM/PAAC-GOx modified electrode versus varying concentrations of glucose was studied at a potential value of −0.7 V (Ag/AgCl). When the data obtained from these surfaces can be prepared in a short time, it was determined that they are sensitive to the presence of glucose in food samples such as cola and fruit juice. One of the innovations of this study is the shortening of the response time and the easy preparation of the biosensor. In addition to high linearity, short response time and long shelf life advantages in determining the glucose content in foods, it is thought that it will be an economical alternative with its easy preparation, ease of application and time and chemicals gain in measurements.
Afficher plus [+] Moins [-]Evaluation of Spermatological Parameters of Karayaka Ram Grown in Ordu Province Texte intégral
2019
Fatih Ahmet Aslan | Hilal Tozlu Çelik | Yeliz Kaşko Arıcı | Kalbiye Konanç | Metehan Eser Kahveci | İbrahim Kiper
The aim of this study was to determine the macroscopic and microscopic spermatological parameters of the Karayaka rams grown in public hands. Out off-season sperm couldn’t be taken from the rams. During the season, semen was collected from all 2-4 age of Karayaka rams (n = 10). Weight (kg) and circumference of the scrotum (cm) were also recorded. When the collected spermatozoa were examined, it was found that the weight variable correlated only with the pH variable. The correlation coefficient calculated between weight and pH was -0,802 and it was found to be statistically significant. The correlation coefficient, which calculated as 0.680, between the circumference of the scrotum (cm) and mortality (% Dead-Live) shows that one feature increases while the other increases significantly. Viscosity (1-5) was correlated only with mass activity (Mass Activity 0-4), and the degree of this relationship was calculated as -0.655. Variables were not associated with sperm volume (ml), motility (%) and density (109).
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