Antioxidant Activity, Phenolic Content, and Peroxide Value of Essential Oil and Extracts of Some Medicinal and Aromatic Plants Used as Condiments and Herbal Teas in Turkey

Ozcan, Mehmet Musa,Erel, Ozcan,Herken, Emine Etoz The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.1

The antioxidant activity, total peroxide values, and total phenol contents of several medicinal and aromatic plant essential oil and extracts from Turkey were examined. Total phenolic contents were determined using a spectrophotometric technique and calculated as gallic acid equivalents. Total antioxidant activity of essential oil and extracts varied from 0.6853 to 1.3113 and 0.3189 to $0.6119\;{\mu}mol$ of Trolox equivalents/g, respectively. The total phenolic content of essential oil ranged from 0.0871 to 0.5919 mg of gallic acid/g dry weight. However, the total phenolic contents of extracts were found to be higher compared with those of essential oils. The amount of total peroxide values of oils varied from 7.31 (pickling herb) to 58.23 (bitter fennel flower) ${\mu}mol$ of $H_2O_2/g$. As a result, it is shown that medicinal plant derivatives such as extract and essential oils can be useful as a potential source of total phenol, peroxide, and antioxidant capacity for protection of processed foods.

Investigation of Thiol/Disulfide Balance in Obese Rats with Non-Alcoholic Fatty Liver Disease

Tursun, Serkan,Gulerman, Hacer Fulya,Gazyagci, Serkal,Sahin, Yasar,Erel, Ozcan,Neselioglu, Salim The Korean Society of Pediatric Gastroenterology 2021 Pediatric gastroenterology, hepatology & nutrition Vol.24 No.5

Purpose: Due to the increasing prevalence of obesity worldwide, non-alcoholic fatty liver disease (NAFLD) has reached epidemic dimensions over time. NAFLD is the most common cause of childhood chronic liver disease. There is a relationship between NAFLD and oxidative stress. This study aims to investigate the changes in thiol/disulfide homeostasis parameters to determine the oxidant/antioxidant balance in obese rats with diet-induced NAFLD and healthy rats. Methods: Twelve Wistar albino rats were used in this study. Experimentally produced NAFLD obese rats (n=6) and healthy rats were compared. Experimental NAFLD model was created with a special fatty liver diet (Altromin^® C1063, Fatty Liver Diet, Exclusivet, Lage, Germany). The biochemical and histopathological features of the groups, as well as serum thiol/disulfide homeostasis parameters, were analyzed and compared. Results: In the experimentally induced NAFLD rat model, they gained more weight than the control group. Steatosis (at least grade 2) occurred in all rats fed with special fatty liver diet for 12 weeks. Histopathologically, no high-grade inflammation was observed in rats with experimental NAFLD after feeding a diet for 12 weeks. Results revealed that aspartate transaminase and alanine transaminase levels were high, albumin levels were low, oxidant stress parameters increased, and antioxidant thiol groups decreased. Conclusion: Experimental NAFLD is characterized by increased oxidant stress accompanying fatty tissue in the liver. Analysis of thiol/disulfide homeostasis parameters in NAFLD can be used in further studies to develop effective treatment options.

Can the Thiol/Disulfide Imbalance Be a Predictor of Colchicine Resistance in Familial Mediterranean Fever?

Ahmet Omma,Sevinc Can Sandikci,Orhan Kücüksahin,Murat Alisik,Ozcan Erel 대한의학회 2017 Journal of Korean medical science Vol.32 No.10

Familial Mediterranean fever (FMF) is a chronic autoinflammatory condition characterized by fever attacks and recurrent polyserositis. Subclinical inflammation that persists during attack-free periods can result in oxidative stress (OS) damage. Thiol groups bind to reactive oxygen radicals and protect cells and tissues from OS damage. The aim of this study was to investigate the relationship between thiol-disulfide balance and colchicine resistance in FMF patients during an attack or attack-free period. A newly developed spectrophotometric method was used to measure native thiol (NT) and disulfide (DS) levels in FMF patients and an age-sex matched group of healthy controls. NT and DS levels were compared in FMF patients 1) with vs. without colchicine resistance; and 2) during an attack (FMF-AP) vs. attack-free period (FMF-AFP). A total of 118 FMF patients and 60 healthy controls were studied. NT (P < 0.001) and total thiol (TT) (P < 0.001) levels in FMF patients were significantly lower compared to healthy controls. NT (P = 0.030) and TT (P = 0.010) levels of FMF-AP patients were significantly lower than that of FMF-AFP patients. FMF-AP patients had significantly higher DS levels than FMF-AFP patients (P = 0.039). Compared to FMF patients without colchicine resistance, elevated levels of DS (P = 0.019) but not NT (P = 0.620) and TT (P = 0.718) were found in those with colchicine resistance. Thiol-disulfide homeostasis is altered in FMF patients during an attack period and this imbalance may be associated with colchicine resistance.

Evaluation of Atherosclerotic Risk by Oxidative Contributors in Alcohol Use Disorder

Almila Senat,Esra Kabadayi-Sahin,Ibrahim Sogut,Tomris Duymaz,Ozcan Erel 대한정신약물학회 2023 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.21 No.3

Objective: Alcohol Use Disorder (AUD) is a condition described as the inability to control or stop alcohol consumption. The patients with AUD have an increased risk of developing atherosclerosis-related diseases. The present study aimed to evaluate oxidative contributors of atherosclerotic risk factors in patients with AUD. Methods: The male subjects diagnosed with AUD (n = 45) and the male subjects as control (n = 35) were enrolled in this study. All participants were undergone psychiatric evaluation and sociodemographic tests. Also, serum oxidative contributors of atherosclerosis including myeloperoxidase (MPO), ferroxidase, catalase (CAT), and lipid hydroperoxides (LOOH) were measured. Additionally, serum lipid profile tests and atherogenic indicators including atherogenic index of plasma (AIP) and non-high-density lipoprotein (HDL) cholesterol were also analyzed. Results: The AUD subject had significantly elevated MPO activity and LOOH levels with decreased antioxidant capacity. AIP and non-HDL cholesterol levels, the atherogenic indicators, were also higher in AUD group compared to the control group. We found the MPO activity and LOOH levels were positively correlated with AIP, non-HDL cholesterol levels, and amount of alcohol consumption. Additionally, CAT activity was negatively correlated with duration of alcohol consumption. Conclusion: Our results revealed that MPO and LOOH levels were elevated by severe alcohol intake and the atherogenic indicators, AIP and non-HDL cholesterol, were significantly correlated alcohol induced elevated oxidative risk factors. Therefore, it can be suggested that MPO activity and LOOH levels may be useful to determine jeopardy of atherosclerotic and the therapeutic interventions that reduce oxidative load could be taken into account to prevent atherosclerotic diseases before clinical manifestation.

Dynamic thiol/disulfide homeostasis as a novel indicator of oxidative stress in patients with urolithiasis

Mehmet Giray Sonmez,Betul Kozanhan,Çigdem Damla Deniz,Mehmet Sinan Iyisoy,Muzaffer Tansel Kilinc,Gokhan Ecer,Ahmet Ozturk,Salim Neselioglu,Ozcan Erel 대한비뇨의학회 2019 Investigative and Clinical Urology Vol.60 No.4

Purpose: A dynamic thiol/disulfide balance is pivotal in organizing anti-oxidant defense, detoxification, apoptosis, and enzyme activities, as well as transcription and cellular signal-transfer mechanisms. The connection between urolithiasis and oxidant/antioxidant status, which can be assessed through thiol-disulfide homeostasis (TDH), has not yet been examined. In this study, we evaluated the effects of TDH on the formation, size, and location of stones by examining the associations between TDH parameters and urolithiasis. Materials and Methods: Patients with urolithiasis and healthy controls were recruited. The patients were divided into subgroups in terms of stone size (>15 mm or ≤15 mm) and stone location (nephrolithiasis or ureterolithiasis). TDH parameters were measured using a novel automatic and spectrophotometric method and compared statistically. Results: TDH parameters were different between the urolithiasis and control groups. TDH tended towards the disulfide side in the urolithiasis group. Stone size increased an average 0.14 mm with a 1 µmol/L increase in disulfide level and decreased an average 0.058 mm with a 1 µmol/L increase in native thiol level. Disulfide and native thiol levels were found to be different across patients with stone size >15 mm, ≤15 mm, and controls (p<0.001 and p<0.001, respectively). However, the nephrolithiasis and ureterolithiasis groups were similar in respect of TDH parameters. Conclusions: In this study, it was found that patients with urolithiasis displayed oxidative stress characterized by a TDH tendency towards the disulfide side, and an inadequate antioxidant response identified by a lower level of native thiol as compared with healthy controls.