Volatile Terpene Profiles of Needle and Phloem Tissues of Healthy and Tomicus destruens-Infested Pinus brutia Trees.

Coniferous trees produce secondary or defense chemicals, such as terpenes, against pest insects. Terpenes could serve as constitutive or induced defensive mechanisms, defending the tree from invasive herbivores. The Mediterranean pine shoot beetle Tomicus destruens colonizes stems and branches of Pinus brutia trees and even can kill mature trees during periodic outbreaks. We investigated whether terpene profiles of needle and stem of P. brutia trees differ between health and those infested by T. destruens. We selected 20 healthy and T. destruens-infested trees and analyzed the monoterpenes and sesquiterpenes of their needles and phloem. We found higher concentrations of tricyclene, camphene and p-cymene in the phloem of infested trees. Similarly, the needles of infested trees had higher concentrations of α-pinene, ß-pinene, myrcene, limonene, trans-ß-caryophyllene and α-humulene than healthy trees. These results show that the monoterpene and sesquiterpene profiles of P. brutia trees differed between healthy and infested trees, suggesting that volatile terpenes may be an important part of plant-induced responses against T. destruens.

Two new compounds from endemic Centaurea paphlagonica (Bornm.) Wagenitz and their cytotoxic activities.

Centaurea paphlagonica (Bornm.) Wagenitz is an endemic plant in Turkey. Pyrocatechol, vanillic acid, 3,4-dihydroxy benzoic acid, 5-O-caffeoylshikimic acid, tamarixetin, chlorogenic acid methyl ester, quercetin, 1,3-dicaffeoylquinic acid, tamarixetin-7-O-ß-D-glucopyranoside, quercimetrin, daucosterin, paphlagonicanin B, tamarixetin-7-O-ß-rutinoside, rutin, chlorogenic acid, isoorientin, orientin, 3-O-feruloylquinic acid, quercetagetin-3-methyl ether 6-O-ß-glucopyranoside, diosmetin 6-C-ß-glucopyranoside, quercetagetin 4'-methyl ether 7-O-ß-glucopyranoside, paphlagonicanin A, nepetin, cirsiliol, desacylcynaropicrin, and 8α-O-(2',3'-dihydroxyisobutyryl) desacylcynaropicrin were isolated from both flower and aerial parts of C. paphlagonica. These compounds were identified using 1D and 2D NMR methods and ESI-MS. The MTT assay assessed the antiproliferative activities of all isolated (known and new compounds) compounds on Caco-2, LNCaP, A549, HeLa, and HEK-293 cell lines. The 8α-O-(2',3'-dihydroxyisobutyryl) desacylcynaropicrin demonstrated the highest activity against CaCo-2 and HeLa cancer cell lines.

Assessment of Cytotoxic and Apoptotic Effects of Salvia syriaca L. in Colorectal Adenocarcinoma Cell Line (Caco-2).

This work is aimed to elucidate cytotoxic and apoptotic effects of Salvia syriaca essential oil and its chemical composition by GC-MS. The human colon cancer cells (Caco-2) were treated with different essential oil concentrations for 24 h. Crystal violet test was used to determine cell viability at 630 nm by using an ELISA reader. Apoptotic processes were measured by Annexin V-FITC Apoptosis Assay Kit. Germacrene D (21.77%), trans-ß-ocimene (14.66%), ß-pinene (9.07%), α-cadinol (8.19%) and α-pinene (6.50%) were the main components of oil determined by GC-MS. Moreover, we observed that the cytotoxic effect was increased with an increasing dose of essential oil. The EC50 value was calculated as 63.5 µg/mL. An increase in the percentage of apoptotic cells was observed after treatment of Caco-2 cells with S. syriaca essential oil revealed by image-based cytometry. A nearly 6-fold increase was found in annexin-positive cells after treatment. In terms of mRNA levels, RT-PCR analysis indicated that, although Bax and Caspase-3 were increased, Bcl-2 was decreased after oil treatment. According to our results, S. syriaca essential oil has promising phytochemicals that might be useful in cancer treatment due to their relatively cytotoxic and apoptotic activities in Caco-2 cells.