Antifungal activity of davanone-type sesquiterpenes from Artemisia lobelii var. conescens

Five tetrahydrofuran sesquiterpenes, so-called davanones, and coumarin umbelliferone isolated from Artemisia lobelii All. var. canescens (DC.) Briqu, were tested for antifungal activity. All the compounds inhibited the growth of the applied fungi. The overall activity of one of them, 2-hydroxy-2,6,10-trimethyl-7,10-epoxydodeca- 3,11-dien-5-on, was comparable to that of the antibiotic bifonazole

Leaf n-Alkanes as Characters Differentiating Coastal and Continental Juniperus deltoides Populations from the Balkan Peninsula

The composition of the cuticular n-alkanes isolated from the leaves of nine populations of Juniperus deltoides R. P. Adams from continental and coastal areas of the Balkan Peninsula was characterized by GC-FID and GC/MS analyses. In the leaf waxes, 14 n-alkane homologues with chain-lengths ranging from C22 to C35 were identified. n-Tritriacontane (C33) was dominant in the waxes of all populations, but variations between the populations in the contents of all n-alkanes were observed. Several statistical methods (ANOVA, principal component, discriminant, and cluster analyses) were used to investigate the diversity and variability of the cuticular-leaf-n-alkane patterns of the nine J. deltoides populations. This is the first report on the n-alkane composition for this species. The multivariate statistical analyses evidenced a high correlation of the leaf-n-alkane pattern with the geographical distribution of the investigated samples, differentiating the coastal from the continental populations of this taxon.Ministry of Education, Science and Technological Development of Serbia {[}173029, 172053

Antimicrobial and antioxidative activity of various leaf extracts of Amphoricarpos vis. (Asteraceae) taxa

The antimicrobial and antioxidative activities of diethyl ether, 80% methanol and 50% acetone extracts of the leaves of three Amphoricarpos taxa: A. neumayerianus, A. autariatus ssp. autariatus and A. autariatus ssp. bertisceus (Asteraceae) from the Balkan Peninsula were investigated. The antimicrobial activity was determined by the broth microdilution assay against eight bacterial and eight fungal species. The in vitro antioxidative activity was assessed by the DPPH assay, The total phenolic and flavonoid contents were also determined. The most sensitive bacterial species were Bacillus cereus and Staphylococcus aureus. The best antibacterial potential was obtained for the methanol extract of A. neumayerianus, while the diethyl ether extract of tins species showed the lowest effect. In general, the tested extracts showed higher activity than the commercial antibiotics streptomycin and ampicillin. Also, all micromycetes were sensitive to the tested extracts. The most sensitive was Trichoderma viride. The highest and lowest antifungal effect was determined in A. a. sspo autariatus for the diethyl ether and acetone extracts, respectively. The highest total phenolic and flavonoid contents were determined in the methanol extract of A. a. autariatus. The best antioxidative activity was shown by the methanol extract of A. a. ssp. autariatus as comparing to matching extracts from the other two taxa

Leaf n-Alkanes as Characters Differentiating Coastal and Continental Juniperus deltoides Populations from the Balkan Peninsula

The composition of the cuticular n-alkanes isolated from the leaves of nine populations of Juniperus deltoides R. P. Adams from continental and coastal areas of the Balkan Peninsula was characterized by GC-FID and GC/MS analyses. In the leaf waxes, 14 n-alkane homologues with chain-lengths ranging from C22 to C35 were identified. n-Tritriacontane (C33) was dominant in the waxes of all populations, but variations between the populations in the contents of all n-alkanes were observed. Several statistical methods (ANOVA, principal component, discriminant, and cluster analyses) were used to investigate the diversity and variability of the cuticular-leaf-n-alkane patterns of the nine J. deltoides populations. This is the first report on the n-alkane composition for this species. The multivariate statistical analyses evidenced a high correlation of the leaf-n-alkane pattern with the geographical distribution of the investigated samples, differentiating the coastal from the continental populations of this taxon.Ministry of Education, Science and Technological Development of Serbia {[}173029, 172053

Chemical composition, antibacterial and antifungal activity of the essential oils of Cotinus coggygria from Serbia

Essential oils from leaves with young branches of Cotinus coggygria Scop. from two localities in Serbia (Deliblatska pescara and Zemun), obtained by hydrodistillation, were analysed by GC–MS. Thirty-one component were identified from both oils and among them monoterpenic hydrocarbons were the dominant class (87.4 and 93.1 %). The dominant constituent in both essential oils was limonene (47.0 and 39.2 %). Both oils were also tested for antibacterial and antifungal activities. In comparison to streptomycin, both oils showed slightly higher activity (against most Gram-positive bacteria) in the disc diffusion method and slightly lower activity when the microdilution method was employed. They also exhibited antifungal potential higher than that of the commercial fungicide bifonazole