Kaan Polatoğlu

Essential Oil Composition of Centaurea stenolepis Kerner. from Turkey

Abstract: Essential oil composition of Centaurea stenolepis Kerner flowers and stems were investigated with GC, GC-MS. Flowers and stems of C. stenolepis had very low essential oil yield <0.01 % (v/w). Twenty eight compounds were identified in the flower oil which represent 53.5 % of the oil. Main components of the flower oil include caryophyllene oxide 12.6 %, hexadecanoic acid 10.6 % and β-Eudesmol 7.2 %. Forty compounds were identified in the stem oils which represent 74.2 % of the oil. Main components of the stem oils include hexadecanoic acid 38.4 % and phytol 12.9 %. Both flower and stem oils were rich on oxygenated sesquiterpene hydrocarbons and fatty acids.

Sitophilus granarius L. (Coleoptera) Toxicity and Biological Activities of the Essential Oils of Tanacetum macrophyllum (Waldst. & Kit.) Schultz Bip.

Insecticides of the natural origin are an important alternative to the synthetic insecticides that are being employed for the preserving stored products. The volatiles obtained from T. cinerariifolium (=Pyrethrum cinerariifolium) is being used for many types of insecticidal applications; however there is a very little information on the insecticidal activity of the essential oils of other Tanacetum species. The main purpose of the present study is to determine the chemical composition of T. macrophyllum (Waldst. & Kit.) Schultz Bip. essential oils and evaluate their insecticidal activity against S. granarius as well as its other beneficial biological activities. Highest contact toxicity was observed in the leaf oil of (88.93%) against S. granarius. The flower oil showed considerable fumigant toxicity against L. minor at 10 mg/mL application concentration (61.86 %) when compared with other samples at the same concentration. The highest DPPH (2,2-Diphenyl-1-picrylhydrazyl) scavenging activity (47.7%) and phosphomolybdenum reducing activity was observed also for the flower oil of T. macrophyllum at 10 mg/mL concentration. The essential oils were analyzed by GC, GC/MS. The flower and leaf oils were characterized with γ-eudesmol 21.5%, (E)-sesquilavandulol 20.3%, copaborneol 8.5% and copaborneol 14.1%, 1,8-cineole 11%, bornyl acetate 9.6%, borneol 6.3% respectively. AHC analysis of the qualitative and quantitative data obtained from the essential oil composition of the T. macrophyllum essential oil from the present research and previous reports pointed out that two different chemotypes could be proposed with current findings which are p-methyl benzyl alcohol/ cadinene and eudesmane chemotypes.

Essential Oil Composition of Endemic Arabis purpurea Sm. & Arabis cypria Holmboe (Brassicaceae) from Cyprus.

There are very few reports on the phytochemistry of the Arabis L. (Brassicaceae) species in the literature. Here we present essential oil composition of aerial parts of two endemic Arabis species from Cyprus. The essential oils of Arabis purpurea Sm. and Arabis cypria Holmboe afforded very low oil yields (< 0.01% (v/w) yield). Sixty six compounds were identified in the essential oil of A. purpurea that represent 82.75 ± 0.21 % (n = 3) of the oil. The major components of the oil were nonacosane 16.18 ± 0.13 %, heptacosane 14.91 ± 0.17 %, hexahydrofarnesyl acetone 12.44 ± 0.10 % and phytol 7.36 ± 0.10 % (n = 3). Forty three compounds were identified in the essential oil of A. cypria which represent 81.28 ± 1.55 % (n = 3) of the oil. The major components of the oil were nonacosane 20.25 ± 0.47 %, heptacosane 9.13 ± 1.88 %, hexahydrofarnesyl acetone 9.03 ± 0.44 % and 1-tetradecanol 4.38 ± 2.60 % (n = 3). To the best of our knowledge this is the first report on the essential oil compositions of these species.

Unexpected Irregular Monoterpene “Yomogi Alcohol” in the Volatiles of the Lathyrus L. species (Leguminosae) of Cyprus

Lathyrus species including L. ochrus and L. sativus are known for their food, feed and horticultural uses. Despite their widespread uses and cultivation, there is limited information on their chemistry. Previously, only the essential oil composition of L. rotundifolius, L. vernus and volatiles of L. odoratus have been reported. In the present research, volatiles of seven Lathyrus L. species, namely, L. aphaca, L. ochrus, L. cicera, L. sativus, L. gorgonei, L. saxatilis and L. blepharicarpos var. cyprius were analyzed by SPME GC-MS for the first time. Plant materials were collected from five different locations in Cyprus (February-March 2012). The main components of L. aphaca volatiles from four locations were yomogi alcohol 26.1-16.5%, camphor 21.6-10.1%, tetradecane 14.3-0%; L. cicera from five locations were yomogi alcohol 20.3-3.0%, camphor 18.7-2.0%; L. gorgonei from two locations were yomogi alcohol 24.5-13.1%, camphor 17.1-9.0% and L. sativus was yomogi alcohol 11.4%, camphor 9.0%. Yomogi alcohol was not present as the major compound in L. ochrus (2-methyl butanoic acid 7.2%), L. saxatilis (hexanal 7.7%) and L. blepharicarpos var. cyprius ((Z)-3-hexenal 8.6%) volatiles. The volatiles of the Lathyrus species were also compared with each other quantitative and qualitatively using AHC analysis to find out differences among the species. The irregular monoterpene yomogi alcohol is reported from the Lathyrus and the Leguminosae family for the first time. The existence of yomogi alcohol in Lathyrus volatiles points out that the irregular monoterpenes are not restricted solely to Asteraceae family.

Biologically Active Essential Oils against Stored Product Pests

Abstract Since the mid-1980s significant attention has been given to essential oils for their potential use in alternative pest management of stored products. Existing synthetic pesticides including methyl bromide and phosphine which are used as fumigants for pest management of stored products have serious adverse properties. These include their toxicity against nontarget organisms, long half-life in the field, and contamination of air/soil/water, etc. In addition to these adverse effects, stored product pests develop resistance to these control agents. The growing world population and increasing food demand together with increasing environmental concerns of society dictates an alternative method for the protection of precious food material. Essential oils produced by plants contain a vast array of secondary metabolites such as derivatives of monoterpenes, sesquiterpenes, diterpenes, aromatic compounds, hydrocarbons, and fatty acids. Plants produce essential oils for various purposes. Essential oils are used for attracting pollinators, deterring herbivores, effecting the growth of competitor plant species, and fighting fungal, bacterial, and viral plant diseases in plants. The volatile nature of essential oils and their known action on herbivores makes them a strong alternative in pest management of stored products. This chapter reviews the insecticidal activity of essential oils obtained from various plant species against main granary pests including Sitophilus granarius (L.), Sitophilus oryzae L., and Sitophilus zeamais Motschulsky species of Coleoptera: Curculionidae. In the scope of this chapter essential oil composition and type of activity observed against these pests are summarized, as well as potential areas of research and future prospects.