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The composition of essential oils from leaves of Kazakhstan medicinal plants was analysed by GC-MS. The major compounds identified were 1,8-cineole (34.2%), myrcene (19.1%) and α-pinene (9.4%) in Ajania fruticulosa; 1,8-cineole (21.0%), β-thujone (11.0%), camphor (8.5%), borneol (7.3%) and α-thujone (6.5%), in Achillea nobilis; camphor (47.3%), 1,8-cineole (23.9%), camphene (9.8%) and β-thujone (6.0%) in Artemisia terrae-albae; 1,8-cineole(55.8%) and β-pinene (6.2%) in Hyssopus ambiguus; α-thuyene(46.3%) and δ-cadinene(6.3%) in Juniperus sibirica; sabinene (64%) in Juniperus sabina; and α-pinene (51.5%), β-phellandrene (11.2%) and δ-cadinene (6.3%) in Pinus sibirica. The essential oils did not show antifungal effect (MIC > 1.20 mg/mL) on Aspergillus carbonarius and Aspergillus niger, while the oils from A. nobilis, A. terrae-albae, H. ambiguus and J. sabina exhibited moderate and moderate to weak antimicrobial activities on Fusarium verticillioides (MIC = 0.60 mg/mL) and Fusarium graminearum (MIC = 0.60-1.20 mg/mL), respectively. A principal component analysis associated the antifungal activity (r > 0.80, p = 0.05) with the presence of borneol, camphor, camphene, 1,8-cineole,α- and β-thujone, and of the oxygenated monoterpenes.

Essential oils from aerial parts of Senecio nutans, Senecio viridis, Tagetes terniflora and Aloysia gratissima were analysed by GC-MS and their antifungal activities were assayed on toxigenic Fusarium and Aspergillus species. Sabinene (27.6±0.1%), αphellandrene (15.7±0.3%), o-cymene (9.6±0.2%) and β-pinene (6.1±0.2%) in S. nutans, 9,10-dehydrofukinone (92.7±0.2%) in S. viridis, β-thujone (36.1±0.1%), αthujone (32.2±0.2%), 1,8-cineol (10.7±0.1%) and sabinene (6.2±0.2%) in A. gratissima, and cis-tagetone (33.6±0.2%), cis-β-ocimene (17.1±0.2%), trans-tagetone (17.0±0.1%), cis-ocimenone (8.0±0.2%) and trans-ocimenone (8.2±0.1%) in T.terniflora. The oils showed moderate antifungal activity (1.2 mg/mL > MIC > 0.6 mg/mL) on the Fusarium species and a weak effect on Aspergillus species. The antifungal activity was associated on F. verticillioides to the high content of cistagetone, trans-tagetone, cis-β-ocimene, cis-ocimenone, trans-ocimenone and on F. graminearum due to the total content of oxygenated sesquiterpenes and 9,10dehydrofukinone. The oil of S. viridis synergized the effect of fungicides and food preservatives on F. verticillioides.

Chemical composition and insecticidal activity of essential oils from cultivated and native aromatic plants of Argentina against Carpophilus dimidiatus (Fabricius)(Nitidulidae) and Oryzaephilus mercator (L.

Extracts from aerial parts of medicinal plants from northwest Argentina were screened for antibacterial activity against the phytopathogenic strains namely CECT 124 (Pseudomonas corrugata), CECT 126 (P. syringae pv. tomato), CECT 225 (Erwinia carotovora var. carotovora), CECT 472 (Agrobacterium tumefaciens) and CECT 792 (Xanthomonas campestres pv. vesicatoria). Leaves and stems of Aspidosperma quebracho-blanco, Schinus fasciculatus, S. gracilipes, Amphilophium cynanchoides and Tecoma stans were separately extracted with solvents of increasing polarity to obtain the dichloromethane (fCH 2 Cl 2 ), ethyl acetate (fEtAc) and methanol extracts (fMeOH), respectively. Among the thirty extracts tested, only fEtAc from leaves and stems of S. fasciculatus reached the IC 50 against the five bacterial strains tested (IC 50 =0.9 mg/ml).The fEtAc from the leaves contained kaempferol, quercetin and agathisflavone which had moderate to strong antibacterial activity. This extract and its identified flavonoids showed synergic (CECT 124,126 and 792) or additive effects (CECT 472 and 225) in mixtures with Kocide 3000.