Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2025Biological activities and phenolic content of endemic Helichrysum artvinense P.H. Davis et Kupicha (Asteraceae)
Acet, Tuba; Özcan, Kadriye; Kalmuk, Nursen Aksu
Species from the Asteraceae family have been extensively utilized in traditional medicine and as food sources for centuries. They also exhibit important biological activities attributed to their diverse array of phytochemical compounds. This research aimed to determine total phenolic and flavonoid contents of ethanol (EtOH) and methanol (MeOH) extracts of endemic Helichrysum artvinense and to reveal its antioxidant, antimicrobial enzyme inhibitory (α-glucosidase, α-amylase, and tyrosinase) and DNA protective activities. In addition, phenolic compound analyses were conducted using high-performance liquid chromatography (HPLC), establishing a correlation with the aforementioned biological activities. Based on the obtained data, the ethanol (EtOH) extract of the plant demonstrated greater prominence in terms of the screened biological activities. This extract was found to contain significant phenolic components, including epicatechin, chlorogenic acid, and luteolin. Consequently, it appears that the plant has the potential to serve as a natural alternative in both food and pharmacological applications. However, further studies to elucidate the mechanisms underlying the observed biological activities would be beneficial for the product development phase.
- MakaleAçık Erişim2022Investigation of the effects of different extraction methods on some biological activities of Dactylorhiza romana subsp. georgica (Klinge) Soó ex Renz & Taubenheim
Bozkir, Buğra; Acet, Tuba; Özcan, Kadriye
Dactylorhiza romana subsp. georgica is found in Anatolia and is traditionally used by local people both as food and to alleviate various ailments. Although various biological activities of the plant have been partially investigated, these properties have not been comprehensively revealed in the light of scientific data. In this study, it was aimed to elucidate the antioxidant, antimicrobial, enzyme inhibition (alpha amylase, alpha glucosidase, and tyrosinase) and DNA protective activity and phenolic content of the extracts obtained from orchid tubers using different extraction methods. For this, the fresh and dry tubers of the plant were extracted with ethanol at different times in an ultrasonic water bath, shaker and their combinations with each other. ABTS, DPPH, and FRAP methods were used to determine the antioxidant properties of plant tubers. In addition, the phosphomolybdate method was used to determine the total antioxidant capacity. The spectrophotometric method was preferred to reveal the enzyme inhibition activity. The antimicrobial activity of the extracts was investigated by microdilution method. In addition, the phenolic content of the plant was analysed by HPLC. The DNA protective activity of the extracts was determined by using the pUC 19 plasmid. According to the results obtained, it was revealed that each extract exhibited various biological activities. According to the HPLC results, the highest phenolic component in the extracts was determined as p-hydroxybenzoic acid. As a result, it was observed that the biological activities of orchid tubers changed according to different extraction methods. Accordingly, due to the high biological activities of orchid tubers, they have a high potential for use in the food and pharmaceutical industries.
- MakaleYalnız künye2021Biological activity of Psephellus appendicigerus as a natural agent
Acet, Tuba; Özcan, Kadriye; Sefalı, Abdurrahman
Psephellus appendicigerus, is a plant endemic to Turkey, belonging to the Asteraceae family, which is traditionally used in folk medicine in Turkey. The aim of this study is to reveal for the first time the biological activities of this plant and evaluate its potential use as a natural product. For this reason, different extracts (ethanol, methanol, ethyl acetate, and hexane) of the plant’s aerial parts were used in determining the antioxidant (2,20-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid and 1,1-diphenyl-2-picrylhydrazyl assays), antimicrobial (disc diffusion and microdilution methods), and enzyme inhibition activity (calorimetric methods) related to diabetes (α-amylase and α-glucosidase). Moreover, the phenolic constituents were analysed by high performance liquid chromatography. Methanol extract of the plant exhibited significant biological activity compared to other extracts. This extract had the highest amount of chlorogenic acid as phenolic compound. In addition, all extracts showed inhibition against at least one test microorganism. According to the results, P. appendicigerus has the potential to be used as a natural antioxidant, antimicrobial and enzyme inhibitor.
- MakaleAçık Erişim2021Phenolic contents and biological activities of two endemic plants in Turkey
Acet, Tuba; Çorbacı, Cengiz; Özcan, Kadriye
In the paper, the phenolic compounds and biological activity of Corydalis oppositifolia DC. and Senecio cilicius Boiss., the endemic plants growing in Turkey, were investigated for the first time. The ethanol extract of C. oppositifolia exhibited more potent antimicrobial activity while the ethanol extract of S. cilicius exhibited the highest radical scavenging activity on ABTS (81.4±1.1a mg TE g−1 extract) and DPPH (23.4±0.2a mg TE g−1 extract). In C. oppositifolia, the highest total flavonoid and phenolic acid contents were found to be in the ethanol (94.2±3.5a mg QE g−1 extract) and methanol (320.5±3.3c mg GAE g−1 extract) extracts, respectively. In S. cilicius, the highest total flavonoid and phenolic acid contents were found to be in the methanol (56.9±0.9c mg QE g−1 extract) and ethanol (568.0±3.3a mg GAE g−1 extract) extracts, respectively. The ethanol extract of C. oppositifolia has the most prominent activity against α-amylase, AChE and BChE whereas the methanol extract of this plant displayed the highest inhibitory activity against α-glucosidase. HPLC analysis of the ethanol extracts revealed that the major flavonoids were kaempferol and quercetin whereas the major phenolic acids were protocatechuic acid, gallic acid, gentistic acid and 2,4-dihydroxybenzoic acid. The findings suggested that the plants and their extracts have the potential to be used in the treatment of diseases such as diabetes and Alzheimer's diseases.
- MakaleYalnız künye2020Phytochemical profile and biological activity of a therapeutic orchid from Anatolia: Dactylorhiza romana subsp. georgica
Kotiloğlu, Deniz; Acet, Tuba; Özcan, Kadriye
In Anatolia, the tubers of Dactylorhiza romana subsp. georgica orchid are consumed as food and frequently used in folk medicine to alleviate the symptoms of some disorders. However, these properties have not been scientifically studied until the present day. In this research, we aimed to identify phenolic profile of the orchid tubers and determine their several features and functions. Among these, there are the antioxidant and antimicrobial effects and the inhibitory effect against diabetes related enzymes (α-amylase and α-glucosidase). In this sense, total phenolic content (Folin–Cicalteu assay), total antioxidant capacity (Phosphomolybdate method), antioxidant (ABTS and DPPH assays) and enzyme inhibition effects of tuber extracts obtained with different solvents (chloroform, ethyl acetate, methanol, ethanol, or hexane) were determined by using spectrophotometric methods, and the phenolic profile was also analysed by HPLC. In addition, antimicrobial activity of the extracts against 3 g (+) and 3 g (−) bacteria and 2 forms of yeasts was determined by disc diffusion and micro dilution methods. Based on our findings, the total phenolic content and antioxidant properties of ethyl acetate extract were considerably higher than the others. The most abundant among the screened phenolic standards was found to be benzoic acid. The highest α-amylase and α-glucosidase enzyme inhibition was measured in methanol and chloroform extracts, respectively. The highest antibacterial (B. cereus) and anticandidal (C. tropicalis and C. albicans) activities were detected in the chloroform and ethyl acetate extracts, respectively. In short, it was clearly seen that the D. romana subsp. georgica tuber had a great potential for being used in food and drug industries as a source of bioactive compounds.
- MakaleAçık Erişim2019Centaurea hypoleuca DC: Phenolic content, antimicrobial, antioxidant and enzyme inhibitory activities
Özcan, Kadriye; Acet, Tuba; Çorbacı, Cengiz
Centaurea hypoleuca is one of the plants have been traditionally used in treatments of many diseases in folk medicine in Turkey. In the present study, ethanol, methanol, and ethyl acetate extracts of the plant's aerial parts were examined and their antioxidant, antimicrobial, and enzyme inhibition activities were determined for the first time. The antioxidant assays were performed in vitro using ABTS and DPPH methods, whereas the antimicrobial efficiency was determined using disc diffusion and microdilution methods. Moreover, the enzyme inhibition activity was analyzed using calorimetric methods targeting the key enzymes used in the treatment of Alzheimer's disease (cholinesterase) and diabetes (glucosidase and amylase). Also, the phenolic contents were analyzed using HPLC. The biological activity of flower ethyl acetate extract was found to be significantly higher than those of other extracts. This extract was more prominent because of its strong antimicrobial activity with the MIC value of 8 µg mL−1 against MRSA. Moreover, the main components of the extract were determined to be catechin and chlorogenic acid. In conclusion, these results indicate that C. hypoleuca can be pharmaceutically used as herbal remedies for its antioxidant, antimicrobial, and enzyme inhibitor effects.