Browsing by Author "Gurbuz, Semra"

Now showing 1 - 6 of 6

Citation - WoS: 22
Citation - Scopus: 22
Aflatoxin M1 in Human Breast Milk in Southeastern Turkey
(Springer Heidelberg, 2017) Altun, Serap Kilic; Gurbuz, Semra; Ayag, Emin
This study was performed to determine aflatoxin M-1 (AFM(1)) in human breast milk samples collected in AanlA +/- urfa, located in Southeastern region of Turkey, and to investigate a possible correlation between AFM(1) occurrence (frequency and levels) and sampling seasons. Human breast milk samples collected in December 2014 and in June 2015 from a total of 74 nursing women, both outpatient and inpatient volunteers in hospitals located in AanlA +/- urfa, Turkey, were analyzed using competitive enzyme-linked immunosorbent assay (ELISA) for the presence of AFM(1). AFM(1) was detected in 66 (89.2%) out of 74 samples at an average concentration of 19.0 +/- 13.0 ng/l (min.-max., 9.6-80 ng/l). There was a statistically significant difference between December and June concerning AFM(1) levels (p < 0.05). Further detailed studies will be needed to determine the main sources of aflatoxins in food, to establish protection strategies against maternal and infant exposure to these mycotoxins.
Chemometric Differentiation of Organic Honeys From Southeastern Türkiye Based on Free Amino Acid and Phenolic Profiles
(MDPI, 2025) Gurbuz, Semra; Kivrak, Seyda
Verifying the geographical origin of honey is crucial for its market value and for preventing fraudulent practices. This study aimed to characterize the chemical profiles of organic honeys from three distinct regions in Southeastern T & uuml;rkiye-& Scedil;& imath;rnak Fara & scedil;in, Siirt Merkez, and Siirt Pervari-to establish a robust method for geographical authentication. A total of 51 multifloral honey samples were analyzed. The concentrations of 20 free amino acids (FAAs) and 16 phenolic compounds were quantified using (UPLC-ESI-MS/MS). The resulting data were subjected to both an unsupervised (PCA, CA) and supervised (PLS-DA, RF, SVM) chemometric analysis to identify biochemical markers for each region. The results revealed a distinct chemical fingerprint for each region. Based on the FAA profiles, the PLS-DA method provided the best overall classification, achieving an excellent discrimination with a total accuracy of 94.1% in the & Scedil;& imath;rnak Fara & scedil;in honeys. For the phenolic compound profiles, the RF method achieved the highest correct classification rate for & Scedil;& imath;rnak Fara & scedil;in honeys at 88.2%. This study demonstrates that an integrated approach, combining FAA and phenolic profiles with supervised chemometric methods, provides a successful and reliable model for determining the geographical origin of these multifloral honeys.
Comparative Evaluation of Machine Learning Models for Discriminating Honey Geographic Origin Based on Altitude-Dependent Mineral Profiles
(MDPI, 2025) Gurbuz, Semra; Kivrak, Seyda
Authenticating the geographical origin of honey is crucial for ensuring its quality and preventing fraudulent labeling. This study investigates the influence of altitude on the mineral composition of honey and comparatively evaluates the performance of chemometric and machine learning models for its geographic discrimination. Honey samples from three distinct altitude regions in T & uuml;rkiye were analyzed for their mineral content using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Results revealed that Calcium (Ca), Potassium (K), and Sodium (Na) were the predominant minerals. A significant moderate negative correlation was found between altitude and Ca concentration (r = -0.483), alongside a weak negative correlation with Copper (Cu) (r = -0.371). Among the five supervised models tested (Partial Least Squares-Discriminant Analysis (PLS-DA), Random Forest (RF), Support Vector Machine (SVM), Extreme Gradient Boosting (XGBoost), and Artificial Neural Network (ANN)), PLS-DA achieved the highest classification accuracy (94.9%). Variable importance analysis consistently identified Ca as the most influential discriminator across all models, followed by Barium (Ba) and Cu. These minerals, therefore, represent key markers for differentiating honey by geographical origin. This research demonstrates that an integrated model utilizing mineral profiles provides a robust, practical, and reliable method for the geographical authentication of honey.
Citation - WoS: 12
An Enzyme-Linked Immunosorbent Assay for Brucella Specific Antibody and Real-Time PCR for Detecting Brucella Spp. in Milk and Cheese in Sanliurfa, Turkey
(UNIV AGRICULTURE, FAC VETERINARY SCIENCE, 2017) Altun, Serap Kilic; Yigin, Akin; Gurbilek, Sevil Erdenlig; Gurbuz, Semra; Demirci, Mehmet; Keskin, Oktay; Tel, Osman Yasar; 11.01. Department of Gastronomy and Culinary Arts / Gastronomi ve Mutfak Sanatları Bölümü; 11. Faculty of Tourism / Turizm Fakültesi; 01. Mardin Artuklu University / Mardin Artuklu Üniversitesi
The objective of this study was to investigate the presence of anti-Brucella antibody and Brucella spp. DNA in cow, sheep and goat milk and in Urfa cheese collected from markets and bazaars in Sanliurfa, located in southeast of Turkey. A total of 258 samples consisting of 178 raw milk (48 cow milk, 65 sheep milk and 65 goat milk) samples and 80 Urfa cheese samples were investigated. Anti-Brucella antibody was detected by indirect ELISA (i-ELISA), and the presence of Brucella spp. DNA was screened by real time Polymerase Chain Reaction (RTPCR). 16.6% of the cow, 6.1% of the goat and 6.1% of the sheep milk and 16.25% of the cheese samples were found as positive for brucella antibodies by i-ELISA. The RT-PCR assay amplified Brucella DNA from 18.75, 7.6 and 6.1% cow, goat and sheep milk samples respectively. Brucella DNA was amplified from 22.5% cheese samples. The 11.2% and 13.9% of the samples were found as positive by i-ELISA and RT-PCR respectively. This study indicates that milk and milk products consumed in Sanliurfa poses a risk to public health in terms of brucellosis. The combining usage of both i-ELISA and RT-PCR methods could lead to more reliable results to detect anti-Brucella antibody and Brucella spp. DNA from milk and cheese samples. (C) 2016 PVJ. All rights reserved
Citation - WoS: 2
Citation - Scopus: 2
Presence of Staphylococcus Aureus, Staphylococcal Enterotoxins and Antimicrobial Resistance in Traditionally Produced Raw Milk Cheeses
(M H Schaper GmbH CO KG, 2018) Gurbuz, Semra; Keskin, Oktay; Gurbilek, Sevil Erdenlig; Tel, Osman Yasar; Yigin, Akin; Demirci, Mehmet; Hassan, Hala
The objectives of this study was to investigate the presence of Staphylococcus aureus, distribution of classical staphylococcal enterotoxin (SE) SEA to SEE, relevant gene/s and antimicrobial resistance pattern of S. aureus isolated from traditionally produced raw milk cheeses. A total of 106 fresh white cheese samples were examined. The 25 (23.6 %) of 106 cheese samples were found to be contaminated with coagulase positive staphylococci (CPS). From 52 isolates identified as S. aureus, one or more SEs was detected in 38.4 % of the isolates by ELISA whereas one or more se genes were detected in 50 % of the isolates by RT PCR. SEE (75 %) and see gene (61.5 %) were detected most frequently, whereas SED and sed gene were not detected in any isolates. Overall, 63.5 % of isolates were resistant to antimicrobial agents with 59.6 %, 13.5 %, 5.8 %, 5.8 % and 3.8 % of the isolates were resistant to penicillin, erythromycin, tetracycline, cefoxitin and kanamycin, respectively. The results of this study have revealed that cheeses made from raw milk were highly contaminated with S. aureus, therefore, creates a risk for public health due to the presence of enterotoxins as well as resistant strains against antimicrobial agents.
Citation - WoS: 5
Simultaneous Screening of Total Aflatoxins (B₁, B₂, G₁, G₂) and Ochratoxin A (OTA) in Coffee Samples
(Parlar Scientific Publications (p S P), 2019) Altun, Serap Kilic; Temamogullari, Fusun; Yigin, Akin; Gurbuz, Semra; 11.01. Department of Gastronomy and Culinary Arts / Gastronomi ve Mutfak Sanatları Bölümü; 11. Faculty of Tourism / Turizm Fakültesi; 01. Mardin Artuklu University / Mardin Artuklu Üniversitesi
The aim of this survey was to determine the occurrence of total aflatoxins (B-1, B-2, G(1), and G(2)) and ochratoxin A (OTA) from different coffee brands and types in the southeastern region of Turkey. Coffee samples (deep-roasted coffee (it is called 'mirra' in Turkey), powdered Turkish coffee, green coffee beans and instant coffee) were collected from supermarkets, retail coffee shops, cafes and touristic bazaars. Total aflatoxins and OTA were microbiologically detected by solid phase direct ELISA. The survey included 90 coffee samples. Survey results demonstrated that 39 (43%) were positive for the presence of total aflatoxins and 36 (%40) out of the 90 samples were positive for the presence of OTA. Total aflatoxin concentrations were found in the range 0.08 - 42.81 mu g kg(-1), only 11 of them exceeded the maximum limit of 10 mu g kg(-1) which is allowed by the European Union for total aflatoxins. OTA levels were range from 0.10 to 41.28 mu g kg(-1); only 9 of the samples exceeded the maximum allowed a limit of 5.0 mu g kg(-1), which is set by the Turkish Food Codex and the European Union. The mean relative humidity level of coffee samples was 5.35. The results of this study has shown the significance of government control programmes in coffee production and sale. This study assessed for occurrence of total aflatoxins and OTA in coffee from different types and brands of coffee.