Gizem Gulsoy Toplan

Dr. Gizem Gulsoy Toplan


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 March 2022 in Molecules
Verified
Journal Article
Open access
PDF file
GTGizem Gulsoy Toplan
Gizem Gulsoy Toplan
TTTurgut Taskin
Turgut Taskin
GİGökalp İŞCAN
Gökalp İŞCAN
FGFatih Göger
Fatih Göger
MKMine Kürkçüoğlu
Mine Kürkçüoğlu
KBKemal Husnu Can Baser
Kemal Husnu Can Baser
The potential applications of Achillea species in various industries have encouraged the examination of their phytochemical components along with their biological potential. In the present study, phenolic contents and essential oil compositions together with the in vitro biological activities of the aerial parts from Achillea biebersteinii Afan. and Achillea millefolium subsp. millefolium Afan. collected from Turkey were evaluated. Different solvent extracts (n-hexane, chloroform, methanol, water) were prepared and their antimicrobial, anticholinesterase, and antioxidant activities were studied. The LC-MS/MS results revealed the presence of 16 different phenolic compounds, including chlorogenic acid, rutin, quercetin, and luteolin glycosides, in methanolic extracts. According to GC-FID and GC/MS results, the primary components of the oils were identified as 1,8-cineole (32.5%), piperitone (14.4%), and camphor (13.7%) in A. biebersteinii and 1,8-cineole (12.3%) and β-eudesmol (8.9%) in A. millefolium subsp. millefolium. The infusion and methanolic extracts of both species were found to be rich in their total phenolic content as well as their antioxidant and anticholinesterase activity. In contrast, the n-hexane and chloroform extracts of both species showed strong antimicrobial activity with MIC values ranging from 15 to 2000 μg/mL. Our findings suggest that the investigated Achillea species could be evaluated as potent natural agents, and further studies into the promising extracts are needed.

1 April 2015 in Journal of Essential Oil Research
Verified
Journal Article
Closed access
GTGizem Gulsoy Toplan
Gizem Gulsoy Toplan
MKMine Kurkcuoglu
Mine Kurkcuoglu
KBKemal Husnu Can Baser
Kemal Husnu Can Baser
GSGunay Sariyar
Gunay Sariyar
The essential oils obtained by hydrodistillation of Vitex agnus-castus L. (Verbenaceae) fruits collected from five different localities in Turkey [Zonguldak (S1), Edirne (S2), Balıkesir (S3), Muğla (S4) and Antalya (S5)] were analyzed by gas chromatography (GC) and GC/mass spectrometry (GC/MS). β-Caryophyllene (11%) and α-pinene (10%) were identified as major components in the oil of S1. The highest amount of bicyclogermacrene (22.1%) was detected in the essential oil of S2. The major components of the essential oil of S3 were 1,8-cineole (17.8%), sabinene (15.8%), (Z)-β-farnesene (13.5%) and bicyclogermacrene (12.1%). The essential oil compositions of S4 and S5 had similarities, both containing sabinene [12.1% (S4), 12.1% (S5)], 1,8-cineole [13.2% (S4), 11.8% (S5)], β-caryophyllene [12.7% (S4), 11.4% (S5)] and bicyclogermacrene [11% (S4), 12.1% (S5)] as major components.

16 November 2020 in Tropical Journal of Pharmaceutical Research
Verified
Journal Article
Open access
PDF file
GTGizem Gulsoy Toplan
Gizem Gulsoy Toplan
EOEsra Eroglu Ozkan
Esra Eroglu Ozkan
TTTurgut Taskın
Turgut Taskın
MAMahmoud Abudayyak
Mahmoud Abudayyak
AMAfife Mat
Afife Mat
GSGunay Sarıyar
Gunay Sarıyar
Purpose: To evaluate the antioxidant and cytotoxic effects, and casticin contents of Vitex agnus-castus (VAC) fruit extract from five geographical regions of Turkey.Methods: Casticin determination in VAC fruit extracts was performed using HPLC-DAD method. The method was validated for linearity, sensitivity, selectivity, accuracy and precision. The methanol extracts of the VAC fruits were analyzed for antioxidant effects using 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging capacity, metal-chelation capacity assay, radical cation scavenging capacity (ABTS•+), and total phenolic content. The cytotoxic potential of the extracts against NRK-52E and HeLa cells were determined using MTT and LDH assays.Results: The casticin content of the extracts ranged from 0.048 and 0.152 %. Total phenol content was in the range of 36.67 ± 0.7 to 74.20 ± 1.02 mg gallic acid equivalent (GAE)/100 mg of extracts. High-tomoderate antioxidant properties were observed in the extracts. Cytotoxicity data demonstrated that all extracts showed high cytotoxic effects on HeLa cell line when compared to the NRK-52E cell line (p < 0.05).Conclusion: These results suggest that VAC fruits (Monk’s pepper fruits) from Aegean sea coasts have a potential for use in the preparation of phytopharmaceutical products. Keywords: Vitex agnus-castus, Casticin, Antioxidant, Cytotoxic activity, Anticancer