Person:
EMRE, GİZEM

Loading...
Profile Picture

Email Address

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

EMRE

First Name

GİZEM

Name

Search Results

Now showing 1 - 3 of 3
  • PublicationOpen Access
    Antioxidant and anti-inflammatory activities of Phlomis pungens and Coridothymus capitatus
    (MARMARA UNIV, FAC PHARMACY, 2018-01-12) YAVUZ, AYŞE NUR; Taskin, Turgut; Cam, Muhammet Emin; Bulut, Gizem; Hazar-Yavuz, Ayse Nur; Kabasakal, Levent; Bitis, Leyla
    The purpose of this study was to comparatively reveal for the first time the antioxidant, anti-inflammatory effects of Phlomis pungens and Coridothymus capitatus methanol extracts obtained by using maceration extraction method. According to the results of anti-inflammatory activity, P. pungens methanolic extract demonstrated a more prominent and intensive antiinflammatory effect with 24.7% of inhibitive capacity in the altered edema size after the first hour of carrageenan injection compared to C. capitatus methanolic extract. P. pungens methanolic extract inhibitory effect increased during three hours and reached maximum by 41.9%. According to the results obtained from antioxidant activity experiments, methanol extract of C. capitatus exhibited stronger free radical scavenging (DPPH), cupric reducing (CUPRAC), ferric reducing/antioxidant power (FRAP) and ABTS radical cation scavenging activity than P. pungens extract. In additon, C. capitatus extract had higher ABTS radical cation scavenging and ferric reducing/antioxidant power activity than ascorbic acid, BHT and BHA, respectively. Therefore, this extract can be used in both medicine and food industry as a natural antioxidant source.
  • Publication
    Biologically active compounds from two members of the Asteraceae family: Tragopogon dubius Scop. and Tussilago farfara L.
    (TAYLOR & FRANCIS INC, 2019) DOĞAN, AHMET; Uysal, Sengul; Senkardes, Ismail; Mollica, Adriano; Zengin, Gokhan; Bulut, Gizem; Dogan, Ahmet; Glamoclija, Jasmina; Sokovic, Marina; Lobine, Devina; Mahomoodally, Fawzi M.
    Tragopogon dubius and Tussilago farfara are consumed as vegetables and used in folk medicine to manage common diseases. Herein, the chemical compositions and biological activities of different leaf extracts (ethyl acetate, methanol, and water) of T. dubius and T. farfara were evaluated. The antibacterial, antifungal, and antioxidant abilities of the extracts were tested using different assays including free radical scavenging, reducing power, phosphomolybdenum, and metal chelating assays. Enzyme inhibitory potentials were evaluated against cholinesterases, tyrosinase, alpha-amylase and alpha-glucosidase. Complexes of bioactive compounds (chlorogenic and rosmarinic acid) were docked into the enzymatic cavity of alpha-glucosidase and subjected to molecular dynamic calculation, enzyme conformational stability, and flexibility analysis. T. dubius and T. farfara extracts showed remarkable antioxidant potentials. Ethyl acetate extracts of T. dubius and T. farfara were the most potent inhibitors of acetylcholinesterase and butyrylcholinesterase. T. dubius ethyl acetate extract and T. farfara methanolic extract showed noteworthy activity against alpha-glucosidase. High performance liquid chromatography analysis revealed the abundance of some phenolic compounds including chlorogenic and rosmarinic acids. Ethyl acetate extract of T. dubius showed notable antifungal activity against all strains. Docking studies showed best pose for chlorogenic acid was stabilized by a network of hydrogen bonds with residues Asp1157, Asp1279, whereas rosmarinic acid showed several hydrogen bonds with Asp1157, Asp1420, Asp1526, Lys1460 and Trp1369. This study further validates the use of T. dubius and T. farfara in traditional medicine, as well as act as a stimulus for further studies for future biomedicine development. Communicated by Ramaswamy H. Sarma
  • PublicationOpen Access
    New biological and chemical evidences of two lamiaceae species (thymbra capitata and thymus sipyleus subsp. rosulans): In vitro, in silico and ex vivo approaches
    (2022-12-01) EMRE, GİZEM; Llorent-Martinez E. J., Ruiz-Medina A., Zengin G., Ak G., Jugreet S., Mahomoodally M. F., EMRE G., Orlando G., Libero M. L., Nilofar N., et al.
    In this study, the methanolic and infusion extracts of two species, Thymbra capitata and Thymus sipyleus subsp. rosulans, were tested for their chemical composition and biological abilities (antioxidant, enzyme inhibitory and anti-inflammatory effects). The extracts yielded total phenolic and flavonoid contents in the range of 83.43-127.52 mg GAE/g and 9.41-46.34 mg RE/g, respectively. HPLC analysis revealed rosmarinic acid to be a major component of the studied extracts (15.85-26.43%). The best ABTS radical scavenging ability was observed in the methanol extract of T. capitata with 379.11 mg TE/g, followed by in the methanol extract of T. sipylus (360.93 mg TE/g). In the CUPRAC assay, the highest reducing ability was also found in the methanol extract of T. capitata with 802.22 mg TE/g. The phosphomolybdenum ability ranged from 2.39 to 3.61 mmol TE/g. In terms of tyrosinase inhibitory effects, the tested methanol extracts (83.18-89.66 mg KAE/g) were higher than the tested water extracts (18.74-19.11 mg KAE/g). Regarding the BChE inhibitory effects, the methanol extracts were active on the enzyme while the water extracts showed no inhibitory effect on it. Overall, the methanolic extracts showed better enzyme inhibition compared to the infusion extracts. Molecular docking also showed the selected exhibited potential binding affinities with all enzymes, with a preference for cholinesterases. Additionally, the extracts were effective in attenuating the LPS-induced increase in COX-2 and IL-6 gene expression in isolated colon, thus indicating promising anti-inflammatory effects. The preliminary results of this study suggest that these species are good natural sources of antioxidants and also provide some scope as enzyme inhibitors, most likely due to their bioactive contents such as phenolic acids, and thus can be exploited for different applications related to health promotion and disease prevention.