Authors:A.I. Korkmaz, H. Akgul, M. Sevindik, and Z. Selamoglu
Lichens are symbiotic associations that are formed by fungi and algae or cyanobacteria. The number of lichen species investigated pharmaceutically is still very low at present. The present study aims to determine the antioxidant activities, antibacterial activities, DNA protective activities, and oxidative stress status of Bryoria fuscescens (Gyeln.) Brodo & D. Hawksw., Parmelina tiliacea (Hoffm.) Hale, and Umbilicaria decussata (Vill.) Zahlbr. Lichens were extracted with ethanol in the Soxhlet device. The DPPH method was used to determine antioxidant activities. DNA protective activity was determined using pBR322 supercoil DNA. Antibacterial activity was determined with dilution test on 5 different species of bacteria (Enterocossus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus). Total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were defined with Rel Assay Diagnostics kits. It was observed that DPPH free radical scavenging activities in lichen ethanol extracts increased with increasing concentration. The highest antioxidant activity was observed in B. fuscescens and the lowest activity was determined in U. decussata. It was also determined that the ethanol extracts of all lichen samples had DNA-protective activity. The highest antibacterial activity was detected in B. fuscescens, while the lowest activity was detected in U. decussata. It was determined that B. fuscescens had the highest oxidative stress index and U. decussata had the lowest value. It appears that the ethanol extracts of the lichen samples utilized in the study could be used as an alternative and complementary resource in medical treatment.
Authors:M. Sevindik, H. Akgul, I. Akata, H. Alli, and Z. Selamoglu
Certain macrofungi species have been used for medical purposes and as nutrients since the old times. The present study aims to determine and compare total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) values, and Fe, Zn, Cu, Pb, and Ni levels in Fomitopsis pinicola (Sw.) P. Karst samples gathered in Balıkesir province Kazdağı National Park and Yalova province Çınarcık Hasan Baba Woods in Turkey. TAS, TOS, and OSI values of mushroom samples were measured with Rel Assay kits. Mushroom heavy metal content was determined using an atomic absorption spectrophotometer and wet decomposition procedure. In the samples collected from Çınarcık district, OSI values were 0.99±0.03, while in the samples collected from Kazdağı National Park, OSI values were 0.13±0.01. Fe content in the samples collected from Çınarcık district were 265.9±70.5 ppm, while Fe content in the samples collected from Kazdağı National Park were 31.31±1.43 ppm. As a result, it is considered that the mushrooms could be used as antioxidant source. Furthermore, it could be argued that as a result of the increase in heavy metal levels, the production of oxidants increases in living organisms, which in turn increases the oxidative stress index.
Authors:F.S. Mohammed, M. Pehlivan, E. Sevindik, H. Akgul, M. Sevindik, I. Bozgeyik, and O. Yumrutas
solvents (MeOH and DCM) from liquid extracts with a Rotary Evaporator. 2.2 Antioxidant activity tests Total antioxidant (TAS), total oxidant status (TOS), and oxidativestress index of the plant samples were determined using Rel Assay kits. Trolox (TAS) and
Authors:O. Koprivnjak, A. Kriško, S. Valić, D. Carić, M. Krapac, and D. Poljuha
: H ENSLEY , K. & F LOYD , R.A. (Eds) Methods in biological oxidativestress: Methods in pharmacology and toxicology . Humana Press Inc. , Totowa, NJ , pp. 161 – 168 .
EC ( 2006 ): Regulation no. 1924/2006, O. J. L
Authors:M. Nogala-Kałucka, K. Dwiecki, A. Siger, P. Górnaś, K. Polewski, and S. Ciosek
The aim of the study was to reveal antioxidant synergism or antagonism between quercetin, rutin and selected tocotrienols in linoleic acid emulsion. The oxidative stress was generated by 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) or CuSO4; the increase of the concentration of peroxidation products was monitored using fluorescence probe 2,7-dichlorofluorescein (DCF). The antioxidant activity of tested substances depends on the form of the antioxidant (aglycone, glycoside), its concentration, localization in the emulsion, and the factors generating oxidative stress. The synergistic effect occurred when the effectiveness of individual antioxidant was relatively weak and mainly when the concentration of antioxidants was in the physiologically significant range of 1 μM. We suggest that tocotrienols were regenerated by flavonoids. The synergism benefitted from the proximity of the localization of interacting antioxidants (e.g. the presence of one of the antioxidants at the oil-water interface).
Authors:M. Kumara, S. Dhillonb, A. Singhala, A. Sooda, M. Ghosha, and A. Gangulia
We investigated the role of salt, ethanol, hydrogen peroxide on the survival and cell surface hydrophobicity (CSH) of Lactobacillus plantarum Ch1 possessing probiotic properties. Survivability of the strain exposed to elevated (3.40 M) ethanol concentration, salt (0.5–2 M), hydrogen peroxide (0.029–0.29 M) was not significantly (P>0.01) affected. With the sole exception of oxidative stress, CSH of intact Lactobacillus plantarum Ch1 increased linearly to the respective stress doses, the observed relationships were supported by strong positive correlations between elevated stress levels and increasing CSH values, suggesting a concentration dependent change in CSH of intact cells. The results of our study imply CSH to be a predominant factor for Lactobacillus plantarum Ch1 to endure stress conditions and may be of substantial importance during designing probiotic foods/beverages containing this strain.