Alper Gökbulut

Adonis sp., Convallaria sp., Strophanthus sp., Thevetia sp., and Leonurus sp. - Cardiotonic Plants with Known Traditional Use and a Few Preclinical and Clinical Studies

Plants have been always a fruitful source of active metabolites against many human disorders, where cardiovascular (CV) diseases have been one of the major health problems all over the world. There are some clinically proved medicinal plants with cardioprotective effects such as Crataegus monogyna and C. oxyacantha (hawthorn) from Rosaceae. On the other hand, cardiac glycosides, present in a number of plant species, are wellknown for their cardiotonic activity. However, we encountered such a fact that very less number of studies are available on the source plants; e.g. Adonis vernalis, Convallaria majalis, Strophanthus kombe, Thevetia peruviana, Leonurus cardiaca, etc. Consequently, we herein aimed to cover all available data consisting of in vitro, in vivo, and human studies (if any) on cardiotonic effects of the aforementioned species through a wide literature search using Scopus, Web of Science as well as Pubmed.

Simultaneous determination of selected phenolic acids in Turkish Salvia species by HPLC-DAD

0009-3130/10/4605-0805 2010 Springer Science+Business Media, Inc. 1) Ankara University, Faculty of Pharmacy, Department of Pharmacognosy, 06100, Ankara, Turkey, fax: (+90312) 2131081, e-mail: gokbulut@pharmacy.ankara.edu.tr; 2) 100. Yil University, Faculty of Education, Department of Biology, Van, Turkey. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 679–680, September–October, 2010. Original article submitted March 16, 2009. Chemistry of Natural Compounds, Vol. 46, No. 5, 2010

Antioxidant and Antimicrobial Activities and Phenolic Compounds of Inula peacockiana and Inula thapsoides ssp. thapsoides

The genus Inula L. is represented in Turkey by 27 species of which eight are endemic. Inula species have been characterized by a high content and diversity of terpenes, phenolics, and glycolipids. In Turkish traditional medicine, Inula species have been used as diuretic, antitussive, expectorant, anthelminthic, and cholagogue [1–3]. Inula peacockiana is a perennial herb up to 2 m, growing naturally in East and Southeast Anatolia. It is an Iranian–Turkish element [1]. We report here for the first time its biological activities and phenolic compound profile. I. thapsoides has two subspecies in Turkey. One of them, I. thapsoides ssp. thapsoides, is a rhizomatous perennial herb up to 1.5 m with winged stem growing naturally in North, West, and Inner Anatolia [1]. A limited number of studies have been performed on this species regarding its essential oil composition and sesquiterpene lactone content [4, 5]. In the current work, Inula peacockiana and Inula thapsoides ssp. thapsoides were investigated for their total phenolic content and antioxidant and antimicrobial activities with the main focus on their phenolic composition. The total phenolic contents of the methanol extracts of the various parts of the species were determined by the Folin-Ciocalteu method, and the results are presented in Table 1. A high amount of phenolics was found in the root extract of I. thapsoides ssp. thapsoides (170.1 5.11 mg GAE/g extract). The extracts obtained by various solvent extractions were analyzed for their antioxidant activities. According to DPPH radical scavenging and ABTS assay results, all the extracts exhibited antioxidant activity in various concentrations (Table 2). The ethyl acetate extracts of the plants exhibited weak antioxidant activity, with high IC50 values, in comparison with the water and methanol extracts. All of the I. thapsoides ssp. thapsoides methanol extracts showed significant antioxidant activity with both methods, especially the root extract. The aqueous extract of I. thapsoides ssp. thapsoides roots was found to exhibit significant antioxidant activity with the ABTS assay, although the obtained results with the DPPH radical scavenging assay was not identical. The aqueous extract of I. peacockiana leaf showed remarkable antioxidant activity with both applied methods. IC50 values of Trolox were found as 0.04 mg/mL for DPPH assay and 0.04 mg/mL for ABTS assay. The antimicrobial activity of methanol extracts of the plant parts was determined by the agar dilution method against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Candida tropicalis. All plant extracts exhibited antibacterial and anticandidal activities, with MIC values ranging from 50 to 400 g/mL (Table 3). I. thapsoides ssp. thapsoides root extract had the highest inhibitory activity against all the microorganisms. All the extracts obtained from I. thapsoides ssp. thapsoides exhibited significant inhibitory activity against E. coli (MIC 100 g/mL). Gram positive bacteria and yeast strains were considerably sensitive to I. peacockiana flower extracts, with MIC values varying from 50 to 100 g/mL. To point out the main principles responsible for the considerable antioxidant and antimicrobial potential of I. thapsoides ssp. thapsoides, and I. peacockiana, some phenolic compounds in the methanol extracts of the plants were determined qualitatively and quantitatively by RP-HPLC equipped with a diode array detector. The retention times, the equations obtained from calibration curves, the test ranges, and the LOD and LOQ values for the standard compounds are given in our previous study [6]. The results indicated that all the investigated plant parts contain chlorogenic and caffeic acids.