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    Chemistry and biological activities of tanacetum chiliophyllum var. oligocephalum extracts
    (Aoac Int, 2013) Polatoğlu, Kaan; Karakoç, Ömer Cem; Demirci, Fatih; Gökçe, Ayhan; Gören, Nezhun
    Tanacetum chiliophyllum (Fisch. & Mey.) var. oligocephalum (D.C.) Sosn. collected in Turkey was subjected to phytochemical and biological evaluations in this study. Pure compounds were obtained from ethyl acetate extracts of the stems of the plant material. Structures of isolated compounds were determined using spectral methods. Seven known flavones, i.e., 5-hydroxy-3',4',6,7-tetramethoxyflavone, eupatilin (6-hydroxyluteolin-6,3',4'-trimethylether), cirsimaritin (scuttellarin-6,7-dimethylether), cirsilineol, 5 hydroxy-3',4',7-trimethoxy flavone, desmethoxy-centaureidin, and jaceosidin and one known triterpene, taraxasterol acetate, were identified from the ethyl acetate extracts. The first seven compounds, as well as the ethyl acetate and methanol extracts, were also investigated for their insecticidal, antimicrobial, and 1,1-diphenyl-2-picrylhydrazil radical (DPPH)-scavenging activities. The insecticidal contact toxicity of the extracts were evaluated on Sitophilus granarius. The ethyl acetate (81.8%) and methanol (88.4%) extracts of T. chiliophyllum var. oligocephalum showed high toxicity against this pest. Most promising antimicrobial activity was observed for ethyl acetate extracts of the stems against Bacillus cereus. This extract showed the same inhibition concentration (125 mu L/mg) with the positive control chloramphenicol. The ethyl acetate (91.9%) and methanol (93%) extracts of the stems showed significant DPPH-scavenging activity compared with the positive controls a-tocopherol (94.5%) and butylated hydroxytoluene (92.9%) at 10 mg/mL concentration. Among the isolated compounds, the highest DPPH-scavenging activity was observed for jaceosidin at 1 mg/mL concentration (81.5%).
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    Insecticidal activity of edible crithmum maritimum L. essential oil against coleopteran and lepidopteran insects
    (Elsevier, 2016) Polatoğlu, Kaan; Karakoç, Ömer Cem; Yücel, Yasemin Yücel; Gücel, Salih; Demirci, Betül; Baser, Kemal Hüsnü Can; Demirci, Fatih
    Crithmum maritimum L. (Apiaceae) is an edible plant that is used in salads or consumed as pickles in Cyprus. In our insecticidal screening study of the plant species of Cyprus, we have studied the insecticidal activity (contact and fumigant toxicity) of the essential oil of Crithmum maritimum against stored product pests Sitophilus granarius L., S. oryzae L., Tribolium castaneum Herbst., T. confusum Jacquelin du Val., Rhyzopertha dominica Fabricius., Oryzaephilus surinamensis L. (Coleoptera) and the field pest Spodoptera exigua (Hubner) (Lepidoptera). Dried leaves of C. maritimum afforded an essential oil with 0.22% (v/w) yield. The essential oil was analyzed with GC, GC-MS and the major components of the oil were identified as gamma-terpinene (39.3%), beta-phellandrene (22.6%), carvacrol methylether (10.5%) and (Z)-beta-ocimene (8.2%). Highest contact toxicity of the oil was observed against S. oryzae, R. dominica and O. surinamensis (1 mu L/insect application of 10% (v/v) oil solution in acetone, after 72 h, 93.30%, 83.26% and 70.33%, respectively). Highest fumigant toxicity was observed for S. granarius, S. oryzae and O. surinamensis (10 mu L/10 mL container application of 10% (v/v) oil solution in acetone, after 48 h, 100.00%, 100.00% and 90.75%, respectively). Essential oil was tested on S. exigua larvae at different development stages (3rd, 4th and 5th instar larvae). 100 mu L/mL essential oil was used with 1, 2 and 4 mu L/larvae concentrations for 3rd, 4th and 5th instar S. exigua larvae, respectively. The toxicity of the oil against the larvae was evaluated after 24 h. C. maritimum essential oil afforded 89% mortality against the 3rd instar larvae however the mortality was decreased to 50% in the 4th and none in the 5th instar S. exigua larvae. The oil also afforded considerable AChE and BChE enzyme inhibition (50.3% and 59.8%, respectively) using the Ellman spectrophotometric method. The essential oil did not produced considerable activity (10(4) fold lower than the positive controls) against the selected pathogens that could be found on wheat (Bacillus cereus, B. subtilis, Salmonella typhimurium, Staphylococcus aureus, Escherichia coli) using a microdilution method for antimicrobial evaluation. (C) 2016 Elsevier B.V. All rights reserved.
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    Öğe
    Insecticidal activity of Salvia veneris Hedge. Essential oil against coleopteran stored product insects and Spodoptera exigua (Lepidoptera)
    (Elsevier Science Bv, 2017) Polatoğlu, Kaan; Karakoç, Ömer Cem; Yücel, Yasemin Yücel; Gücel, Salih; Demirci, Betül; Demirci, Fatih; Baser, Kemal Hüsnü Can
    Salvia species are very well known for their uses as herbal tea as well as insecticidal activity of their essential oils against stored product insects. Due to their use as herbal tea, Salvia species could be considered as perfect candidates to develop safe natural insect management agents. In the scope of the present study, the essential oil of aerial parts of Salvia veneris Hedge was investigated for insecticidal activity against 3rd instar larvae of Spodoptera exigua (Hubner) (Lepidoptera), Sitophilus granarius L., S. oryzae L., Tribolium castaneum Herbst, T. confusum Jacquelin du Val, Rhyzopertha dominica Fabricius and Oryzaephilus surinamensis L (Coleoptera). The essential oil produced 63.0% contact toxicity against the S. exigua (beet armyworm) 3rd instar larvae at 100 mu L/mL and concentration. Highest contact toxicity of the oil was observed at 1 L application volume (10% (v/v: oil/acetone)) and 72 h duration against O. surinamensis 81.6%, S. oryzae 71.5% and S. granarius 70.0%, respectively. S. veneris oil produced the highest fumigant toxicity at 1 mu L/mL application volume (10% (v/v: oil/acetone)) and 48 h duration against S. oryzae 100.0%, S. granarius 97.6% and O. surinamensis 90.8%, respectively. The essential oil tested on Tribolium species and R. dominica did not produced any fumigant toxicity. The acetylcholinesterase and butyrylcholinestearase inhibitory activities of the essential oil were 85.9% and 12.2%, respectively. The antimicrobial activity (minimum inhibitory concentration, MIC) of the oil was tested against the pathogens that could be found on stored products namely Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Bacillus cereus and Bacillus subtilis. The oil produced very weak activity on all of the tested microorganisms when compared with the positive controls. The essential oil composition was analyzed by gas chromatography and gas chromatography/mass spectrometry and the aerial parts of the S. veneris was characterized by 1,8-cineole 30.4%, camphor 18.4%, camphene 12.9%, alpha-pinene 8.2%, borneol 5.8% and beta-pinene 5.0%. As a conclusion the essential oil of S. veneris produced considerable insecticidal activity against Sitophilus species as well as acetylcholinesterase inhibitory activity which points out further attention should be given to Salvia species for the development of safe natural pest management agents. (C) 2016 Elsevier B.V. All rights reserved.