Person: TOPÇU, GÜLAÇTI
80 results
Search Results
Now showing 1 - 10 of 80
Publication Open Access Triterpenoids and steroids isolated from Anatolian Capparis ovata and their activity on the expression of inflammatory cytokines(2020-01-01T00:00:00Z) GAZİOĞLU, IŞIL; Semen, Sevcan; Acar, Ozden Ozgun; KOLAK, Ufuk; Sen, Alaattin; TOPÇU, GÜLAÇTI; GAZİOĞLU, IŞIL; TOPÇU, GÜLAÇTIContext: Capparis L. (Capparaceae) is grown worldwide. Caper has been used in traditional medicine to treat various diseases including rheumatism, kidney, liver, stomach, as well as headache and toothache. Objective: To isolate and elucidate of the secondary metabolites of the C. ovata extracts which are responsible for their anti-inflammatory activities. Materials and methods: Buds, fruits, flowers, leaves and stems of C. ovata Desf. was dried, cut to pieces, then ground separately. From their dichloromethane/hexane (1:1) extracts, eight compounds were isolated and their structures were elucidated by NMR, mass spectroscopic techniques. The effects of compounds on the expression of inflammatory cytokines in SH-SY5Y cell lines were examined by qRT-PCR ranging from 4 to 96 mM. Cell viability was expressed as a percentage of the control, untreated cells. Results: This is a first report on isolation of triterpenoids and steroids from C. ovata with anti-inflammatory activity. One new triterpenoid ester olean-12-en-3b,28-diol, 3b-pentacosanoate (1) and two new natural steroids 5a,6a-epoxycholestan-3b-ol (5) and 5b,6b-epoxycholestan-3b-ol (6) were elucidated besides known compounds; oleanolic acid (2), ursolic acid (3), b-sitosterol (4), stigmast-5,22-dien-3b-myristate (7) and bismethyl-octylphthalate (8). mRNA expression levels as EC10 of all the tested seven genes were decreased, particularly CXCL9 (19.36-fold), CXCL10 (8.14-fold), and TNF (18.69) by the treatment of 26 mM of compound 1 on SH-SY5Y cells. Discussion and conclusions: Triterpenoids and steroids isolated from C. ovata were found to be moderate-strong anti-inflammatory compounds. Particularly, compounds 1 and 3 were found to be promising therapeutic agents in the treatment of inflammatory and autoimmune diseases.Publication Metadata only Natural diterpenoid alysine A isolated from Teucrium alyssifolium exerts antidiabetic effect via enhanced glucose uptake and suppressed glucose absorption(2019-01-01T00:00:00Z) Sen, Alaattin; Ayar, Buket; Yilmaz, Anil; Acar, Ozden Ozgun; Turgut, Gurbet Celik; TOPÇU, GÜLAÇTI; YILMAZ, ANIL; TOPÇU, GÜLAÇTITeucrium species have been used in folk medicine as antidiabetic, antiinflammatory, antiulcer, and antibacterial agents. We have explored in vitro antidiabetic impacts of 2 natural diterpenoids, alysine A and alysine B, isolated from Teucrium alyssifolium. The lactate dehydrogenase (LDH) cytotoxicity assay, glucose uptake test, glucose utilization (glycogen content) test, glucose transport test, glucose absorption (a-glucosidase activity) test, insulin secretion test, RNA isolation and cDNA synthesis assay, qPCR quantification assays, and statistical analyses were carried out in the present study. Alysine A exerted the following effects at non-cytotoxic doses:Publication Metadata only Evaluation of fruit extracts of six Turkish Juniperus species for their antioxidant, anticholinesterase and antimicrobial activities(2011-03-30T00:00:00Z) Ozturk, Mehmet; Tumen, Ibrahim; Ugur, Aysel; Aydogmus-Ozturk, Fatma; Topcu, GÜLAÇTI; TOPÇU, GÜLAÇTIBACKGROUND: Juniperus L. (Cupressaceae) species are mostly spread out in the Northern Hemisphere of the world, and some of them are used as folkloric medicines. The fruits of some species are eaten. Since oxidative stress is one of the reasons for neurodegeneration and is associated with the Alzheimer-s disease (AD), the extracts prepared from the fruits of six Juniperus species were screened for their antioxidant activity. Therefore, the extracts were also evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), which are chief enzymes in the pathogenesis of AD. In addition, antimicrobial activity was also evaluated.Publication Metadata only Investigation of Anticholinesterase Activity of a Series of Salvia Extractsand the Constituents of Salvia staminea(2013-03-01) Topçu, Gülaçtı; Boğa, Mehmet; Kolak, Ufuk; Öztürk, Mehmet; Dirmenci, Tuncay; Bahadori, Fatemeh; Bütün, Burcu; TOPÇU, GÜLAÇTI; BAHADORİ, FATEMEH; BÜTÜN, BURCUPublication Metadata only Investigation of cytotoxic and apoptotic effects of 63 compounds obtained from Salvia species: Promising anticancer agents(2022-05-01T00:00:00Z) Kandemir, Sevgi Irtegun; FİDAN, HİLAL SARUHAN; Yener, Ismail; METE, NURİYE; ERTAŞ, ABDULSELAM; TOPÇU, GÜLAÇTI; KOLAK, Ufuk; TOPÇU, GÜLAÇTISince ancient time, Salvia L. species have been commonly used to treat colds, bronchitis, tuberculosis, heart diseases, and menstrual and digestive disorders in traditional medicine all around the world. They have been also used as tea and spice. Studies indicated that diterpenes and triterpenes isolated from Salvia species possess various pharmacological and biological effects such as anti-inflammatory, antiviral, cytotoxic, antioxidant, and hepatotoxic activities. Flavones were also shown to have antimicrobial, antioxidant, and cytotoxic potentials. Salvia extracts also exhibit anti-Alzheimer, antiseptic, cardiovascular, antihypertensive, and antituberculous effects. To investigate the effects of 63 secondary metabolites from Salvia species on cell viability and apoptosis, Salvia secondary metabolites including 25 phenolics, 4 fatty acids, 19 abietane diterpenoids, 12 triterpenoids, and three steroids were examined on healthy cell line (PDF), breast cancer (MCF-7), and colon cancer (HT-29) cell lines using MTT method. In addition, the effects of rosmarinic acid, 6,7-dehydroroyleanone, acetyl royleanone, ferruginol, carnosic acid, carnosol, cryptotanshinone, beta-sitosterol, and ursolic acid on pro-apoptotic Bax and antiapoptotic Bcl-2 protein expression levels were investigated by Western Blot method. Practical applications Phenolic compounds (apigenin, chrysin, and luteolin) and diterpenes (especially dihydrotanshinone I, carnosic acid, and carnosol), and almost all of the triterpenes exhibited high toxic effects on healthy cell line. Cytotoxic effects of cryptotanshinone, 12-hydroxy abieta-1,3,5(10),8,11,13-hexaene, 12-demethylmulticauline, 6,7-dehydroroyleanone, acetyl royleanone, ferruginol, ursolic acid, and 3-acetyl lupeol were relatively higher than their toxic effects. Acetyl royleanone, 6,7-dehydroroyleanone, carnosic acid, and cryptotanshinone were found to have anticancer potential based on their modulating effects on the expression levels of Bax and Bcl-2 proteins which play important roles in the regulation of apoptosis. The results of the present study showed that acetyl royleanone, cryptotanshinone, 6,7-dehydroroyleanone, carnosic acid, and cryptotanshinone have potential to be used in the pharmaceutical industry.Publication Metadata only Antioxidant and anticholinesterase activities of lupane triterpenoids and other constituents of Salvia trichoclada(2015-11-01) Butun, Burcu; Hatipoglu, Seda Damla; Dönmez, Ayşe; Topcu, Gülaçtı; BÜTÜN, BURCU; TOPÇU, GÜLAÇTIThe methanol extract of the aerial parts of Salvia trichoclada Bentham (Lamiaceae) was studied for bioactive non-volatile secondary metabolites, and nine compounds were isolated. Structures of the isolated compounds were elucidated as lupeol (1), lupenone (2), glochidone (3), monogynol A (4), oleanolic acid (5), ursolic acid (6), beta-sitosterol (7), apigenin-7-O-rhamnoside (8), and rosmarinic acid (9) by using 1D and 2D-NMR spectroscopic techniques. A lupane triterpene glochidone was isolated from a Salvia species and Lamiaceae family for the first time in this study. The antioxidant potential of the extract and the isolated compounds were carried out by using lipid peroxidation inhibitory activity (beta-carotene bleaching method) and DPPH free radical scavenging activity test assays. Their anticholinesterase activity was investigated by the Ellman method against both acetylcholinesterase (AChE) and butyrylcholinesterase enzymes. Compounds 1, 3, 5, 6, 8 and 9 showed fairly high anticholinesterase activity almost at all concentrations. Among them, a flavone glycoside apigenin-7-O-rhamnoside exhibited the highest and selective AChE inhibitory activity. Glochidone (3) was found to be the most active one among the isolated lupanes, which exhibited a close activity to that of standard compound galanthamine. Among all the tested compounds, rosmarinic acid (9) exhibited highest antioxidant and good anticholinesterase activity.Publication Metadata only Special issue in Honour of Professor Ayhan Ulubelen(2011-12-01T00:00:00Z) TOPÇU, GÜLAÇTI; GÖREN, Nezhun; Öksüz, Sevil; TOPÇU, GÜLAÇTIPublication Metadata only Isolation and analysis of bioactive diterpenoids in Salvia species (Salvia chionantha and Salvia kronenburgiii) by micellar electrokinetic capillary chromatography(2010-01-20T00:00:00Z) Öztekin, Nevin; Baskan, Selda; Kepekci, S. Evrim; Erim, F. Bedia; Topcu, Guelacti; TEKKELİ, ŞERİFE EVRİM; TOPÇU, GÜLAÇTIIn the present work, we isolated two bioactive diterpenoids, horminone and 7-O-acetylhorminone and developed a micellar electrokinetic chromatography (MEKC) method for the simultaneous quantitative analysis of them in Turkish Salvia Species. The optimal separation electrolyte was 50 mmol/L SDS and 25% methanol at pH 11.5. The limits of detection (S/N=3) were 3.269 and 4.518 mu g/mL for horminone and 7-O-acetylhorminone, respectively. The method has been applied successfully to analyze these two components in Salvia chionantha and Salvia kronenburgii acetone extracts. (C) 2009 Elsevier B.V. All rights reserved.Publication Metadata only Diterpens and other constituens from Ajuga spp. with cytotoxic activity(2015-08-01) Yapar, Gönül; Uckaya, FATİH; Topcu, GÜLAÇTI; UÇKAYA, FATİH; TOPÇU, GÜLAÇTIPublication Metadata only Complete C-13 NMR assignments for ent-kaurane diterpenoids from Sideritis species(2011-05-01T00:00:00Z) Halfon, Belkis; GOREN, AHMET CEYHAN; Ertas, Abdulselam; Topcu, GÜLAÇTI; GÖREN, AHMET CEYHAN; TOPÇU, GÜLAÇTIIn this work, the detailed NMR studies and full C-13 NMR assignments for five diterpenoids isolated from Sideritis caesarea and Sideritis athoa are described. The assignments are based on a combination of 1D and 2D NMR techniques including H-1, C-13, H-1-H-1 COSY, gHSQC [(1)J(C,H)] and gHMBC delta(C) [(n)J(C,H) (n = 2 and 3)] and NOESY experiments. Copyright (C) 2011 John Wiley & Sons, Ltd.