Idris Arslan

Phytochemical Constituents and Inhibitory Activity towards Methicillin‐Resistant Staphylococcus aureus Strains of Eryngium Species (Apiaceae)

The chemical composition of the essential oils of Eryngium campestre, E. thorifolium, and E. creticum (Apiaceae), growing in the Aegean region of Turkey (Mount Sandras, Denizli), was determined by direct thermal desorption (DTD)‐GC/MS analyses. A total of 49 components were identified in the oils, α‐pinene and hexanal being the major compounds. The three essential oils were also tested for their inhibitory activity of nine different methicillin‐resistant Staphylococcus aureus (MRSA) strains by the agar disc diffusion method. The anti‐MRSA activity of E. thorifolium oil, the most active of the three oils, was comparable with those of the reference antibiotic vancomycin and oregano oil, although somewhat lower.

A cytotoxic triterpenoid saponin from under-ground parts of Gypsophila pilulifera Boiss.& Heldr.

A cytotoxic triterpenoid saponin was isolated from the under-ground parts of Gypsophila pilulifera Boiss.& Heldr. (Caryophyllaceae) naturally grow in the southwestern region of the Turkey. The structures of saponin was elucidated as 3-O-β-D-galactopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucuronopyranosyl quillaic acid 28-O-β-D-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→4]-α-l-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl ester on the basis of extensive spectral analysis and chemical evidence. The separated triterpenoid saponin was isolated from Gypsophila pilulifera for the first time. The saponin compound displayed significant cytotoxicity against A549 cell line with IC(50) values >16μM.

Nebulosides A-B, novel triterpene saponins from under-ground parts of Gypsophila arrostii Guss. var. nebulosa

A bioassay-guided phytochemical analysis of the triterpene saponins from under ground parts of Gypsophila arrostii var. nebulosa allowed the isolation of two triterpene saponins; nebuloside A, B based on gypsogenin and quillaic acid aglycone. Two new oleanane type triterpenoid saponins (nebuloside A, B) and three known saponins (1-3) were isolated from the root bark of Gypsophila arrostii var. nebulosa. The structures of the two new compounds were elucidated as 3-O-β-D-galactopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucuronopyranosyl quillaic acid 28-O-β-D-glucopyranosyl-(1→3)-[β-D-xylopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)]-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl ester (nebuloside A) and 3-O-β-D-xylopyranosyl-(1→3)-[β-D-galactopyranosyl(1→3)-β-D-galactopyranosyl-(1→2)]-β-D-glucuronopyranosyl gypsogenin 28-O-β-D-glucopyranosyl-(1→3)-[β-D-xylopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)]-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl ester (nebuloside B), on the basis of extensive spectral analysis and chemical evidence. Nebuloside A and B showed toxicity enhancing properties on saporin a type-I RIP without causing toxicity by themselves at 15 μg/mL.

Screening of the constituents, antimicrobial and antioxidant activity of endemic Origanum hypericifolium O. Schwartz & P.H. Davis

The chemical compositions, total phenol content, antioxidant and antimicrobial activities with oxidant status of the essential oil from an endemic Turkish species, Origanum hypericifolium, were investigated. Steam distillation (SD) was used to isolate the essential oils, and the chemical analyses were performed by gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity was tested by agar disc diffusion method against Morganella morganii (clinic isolate) , Micrococcus flavus (clinic isolate) , Micrococcus luteus NRLL B-4375, Proteus vulgaris RSKK 96026, Escherichia coli ATCC 11230, Escherichia coli ATCC 25922, Yersinia enterecolitica RSKK 1501, Staphylococcus aureus ATCC 25923, S. aureus ATCC 25933, S. aureus ATCC 12598, S. aureus (clinic isolate), MRSA 1 (clinic isolate), MRSA 2 (clinic isolate), MRSA 3 (clinic isolate) and MRSA 4 (clinic isolate). The major compounds found in volatiles of O. hypericifolium were p-cymene, carvacrol and γ-terpinene. Results showed that O. hypericifolium has the potential for being used in food and medicine because of its antioxidant and antibacterial activity.

Constituents, Oxidant-Antioxidant Profile, and Antimicrobial Capacity of the Essential Oil Obtained from Ferulago Sandrasica Peşmen and Quézel

Chemical constituents, total phenolic content, total oxidant status, total antioxidant status, lipid hydroperoxides, total free –SH levels, and antimicrobial activity of essential oil obtained from the Ferulago sandrasica (Umbelliferae) were investigated. The essential oil was obtained by hydrodistillation using a Clevenger-type apparatus. The chemical constituents were analyzed by gas chromatography‐mass spectrometry. The main components of the essential oil were ocimene (30.5%), carene-δ-3 (27.4%), and α-pinene (17.8). The antimicrobial activity was tested by a disc diffusion method against E. coli MC 400, E. coli ATCC 25922, E. coli 0157 H7, E. colaecea ATCC 23355, E. feacalis ATCC 19433, P. aeruginosa NRRL B-2679, S. aureus ATCC 25923, B. nischenoformis NRRL B-1001, S. aureus ATCC 33862, B. cereus NRRL B-3711, B. subtilis NRRL B-209, M. luteus NRRL B-1013, L. monocytogenes ATCC 7644, B. subtulis ATCC 6633.

CHEMICAL COMPOSITION AND ANTIMICROBIAL ACTIVITY OF ESSENTIAL OIL FROM Nepeta cadmea

The Genus Nepeta L. (Lamiaceae) is represented by 34 species in Turkey, including eighteen endemic species [1, 2]. Nepeta cadmea Boiss. is an endemic species with limited distribution and included in the lower risk and least concern category in the red data book of Turkey [3]. Here we report on the antimicrobial activity of the essential oils from N. cadmea because very little information is available on this endemic species. Table 1 shows the percentages of the main components present in the essential oils isolated from N. cadmea collected in June from Honaz Mountain. The yields of essential oil from N. cadmea on a dry weight basis was 2.1% (v/w). Thirteen components in N. cadmea (97.91%) were identified. The components are listed in order of their elution time on the HP 1 MS column. Among the compounds, nepetalactone (81.6%), caryophyllene (3.71%), and germacrene D (3.25%) were identified as the major components in the essential oil of N. cadmea. The antimicrobial activity of the essential oil measured by the disc diffusion method is given in Table 2. The essential oil isolated from N. cadmea showed antimicrobial activity, but differences in microbial susceptibility were observed. Our findings indicate that the essential oil isolated from N. cadmea has antimicrobial activity and can be used to control microorganisms since this has been used in folk medicine for decades. It will be worth-while to investigate the individual components in antibacterial and antifungal assays.

GPR18 Inhibiting Amauromine and the Novel Triterpene Glycoside Auxarthonoside from the Sponge-Derived Fungus Auxarthron reticulatum.

The marine sponge-derived fungus Auxarthron reticulatum produces the cannabinoid receptor antagonist amauromine (1). Recultivation of the fungus to obtain further amounts for more detailed pharmacological evaluation of 1 additionally yielded the novel triterpene glycoside auxarthonoside (2), bearing, in nature, a rather rare sugar moiety, i.e., N-acetyl-6-methoxy-glucosamine. Amauromine (1), which inhibited cannabinoid CB1 receptors (Ki 0.178 µM) also showed antagonistic activity at the cannabinoid-like orphan receptor GPR18 (IC50 3.74 µM). The diketopiperazine 1 may thus serve as a lead structure for the development of more potent and selective GPR18 antagonists, which are required to study the orphan receptors potential as a new drug target. Despite the execution of many biological assays, to date, no bioactivity could be found for auxarthonoside (2).

Simenoside A, a New Triterpenoid Saponin from Gypsophila simonii Hub.-Mor.

Saponins are amphiphilic glycoconjugates which give soap‐like foams in H2O. A new triterpenoid saponin, simenoside A (1), based on gypsogenin aglycone, and the known saponin 2 were isolated from Gypsophila simonii Hub.‐Mor. The structure of the new saponin was elucidated as 3‐O‐β‐D‐galactopyranosyl‐(1→2)‐[β‐D‐xylopyranosyl‐(1→3)]‐β‐D‐glucuronopyranosylgypsogenin 28‐O‐β‐D‐glucopyranosyl‐(1→3)‐[β‐D‐glucopyranosyl‐(1→2)‐β‐D‐xylopyranosyl‐(1→4)]‐α‐L‐rhamnopyranosyl‐(1→2)‐β‐D‐fucopyranosyl ester on the basis of extensive spectral analyses and chemical evidence. Saponins 1 and 2 were isolated from G. simonii for the first time.

Genotoxicological Assessment of Nebuloside-A a Triterpenoid Saponin Compound on Whole Blood DNA

We investigated the genotoxic effect of nebuloside-A on whole blood DNA by using alkaline Single Cell Gel Electrophoresis Comet assay. Saponins are a widespread class of bioactive compounds produced by many plant species. Nebuloside A was isolated from baby’s-breath (Gypsophila arrostii) by high performance liquid chromatography method. Mass spectra obtained by electrospray ionization-time of flight-mass spectrometry in a negative ion mode to reduce the protonation. Complete nuclear magnetic resonance spectroscopy assignments of nebuloside A was achieved by using 2D-nuclear magnetic resonance spectroscopy techniques, such as double-quantum filtered correlation spectroscopy, heteronuclear single quanthum correlation, heteronuclear multiple-bond correlation, and total correlation spectroscopy. DNA damage was measured in total arbitrary units by visual scoring of comets in different concentrations of nebuloside A and H2O2 treatments. We found that significant dose dependent relationship between nebuloside A and its genotoxic effect.

Free Radical Scavenging Activities and Essential Oil Analysis of Salvia cedronella Boiss. and S. fruticosa Mill.

Abstract The present study was designed to examine the in vitro free radical scavenging activities of the methanol extracts and essential oil analysis of Salvia cedronella (endemic) and Salvia fruticosa from Turkey. Free radical scavenging activity of methanolic extracts were employed by 2,2’-diphenyl-l-picrylhydrazyl (DPPH). The essential oil of S. cedronella and S. fruticosa were analysed by GC-MS. Totally, 27 components were detected in both hydrodistilled oils, the major components of essential oil of S. cedronella were camphor, α-thujone and α-pinene, whereas those of S. fruticosa were 1,8-cineole (eucalyptol), α-thujone and caryophyllene oxide.