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The antifungal activity of Pelargonium capitatum essential oil (PCEO) and Cymbopogon martini essential oil (CMEO) against C.albicans were evaluated. The main components of essential oils were β-cytronellol 58.81% and geraniol 83.94% in PCEO and CMEO, respectively. PCEO was more activity than CMEO for all C.albicans strains tested with values MIC50 or MIC90 of 780 µg/ml. PCEO used in combination with fluconazole or CMEO shows synergistic effect with FICI values ≤ 0.5. Moreover both essential oils are able to inhibit the major virulence factor of C.albicans as the germ tube formation at sub-inhibitory concentration of 195 µg/ml. In conclusion, it is possible to hypothesize that PCEO can be used in combination with fluconazole or CMEO. Further studies are in due course to confirm these results. [ABSTRACT FROM AUTHOR]

Abstract: Relationships between fire history, vegetation structure and composition, and invasion by introduced plant species have received limited attention in Australian woodlands. A study in a Mediterranean, fire adapted urban Banksia woodland remnant in the biodiversity hotspot of southwest Australia investigated: (1) Have significant changes occurred in the woodland tree canopy between 1963 and 2000? (2) Do correlations exist between fire frequency and canopy cover? (3) If there is a difference in the vegetation composition of Banksia woodland invaded by the South African Ehrharta calycina (PCe) and Pelargonium capitatum (PCp) compared to largely intact remnants (GC)? and (4) Do correlations exist between vegetation condition, composition, fire frequency and invasion? Aerial photography, processed in a Geographical Information System, was used to establish fire history and changes in canopy cover over time (1963–2000). PCe and PCp sites experienced the greatest number of fires, with a net reduction in canopy cover in all areas experiencing four or more fires (60% of all woodlands). Frequent fire corresponded with a decline in native cover, richness and diversity, a shift from native to introduced species, changes in the relative importance of fire response categories, and loss of native resprouting shrub cover. Life forms of introduced species, which included no trees, shrubs and perennial sedges, contrasted strongly with those of native species, which had poor representation of annual and perennial grasses. Clear ecological and conservation consequences due to the loss of species diversity, changes in fire ecology and invasion have occurred in the Banksia woodlands. This study provides an understanding of the invasion process, enhancing conservation knowledge to improve the adaptive management of the key threatening process of invasion in biodiverse communities. [Copyright &y& Elsevier]

A plethora of information is available on the essential oil composition of commercially grown Pelargoniums namely P. capitatum, P. graveolens and P. radens and their hybrids, while only a few chemical investigations have been carried out on the other aromatic Pelargonium species indigenous to South Africa. The hydrodistilled leaf oils of 13 South African Pelargonium species of the genus Pelargonium (family Geraniaceae) were analyzed by means of GC and GC/MS and a total of 315 compounds were identified. The oil data was chemotaxonomically informative confirming taxonomic relationships i.e. between P. graveolens and P. radens, P. papilionaceum and P. vitifolium and between P. panduriforme and P. quercifolium. The oil compositions of P. citronellum, P. papilionaceum and P. vitifolium were different with respect to those of the other analyzed species in this study. Geranic acid was the most abundant oil constituent (36.0%) in P. citronellum (provenance NBG), which was the only species in which neral (17.4%) and geranial (27.2%) were detected. Citronellic acid dominated in the oils of P. papilionaceum (provenance NBG) and P. vitifolium (provenance SBG), occurring in amounts of 96.2% and 74.7%, respectively. The major monoterpene identified in P. radens (provenance NBG) and in the samples of P. graveolens (provenances SBG and WSBG) was isomenthone (84.5%, 65.8% and 83.3%, respectively). The P. tomentosum oil samples produced an essential oil rich in menthone (36.1-41.1%) and isomenthone (49.3-56.6%). The latter monoterpenic ketone was responsible for the chemical affinity demonstrated among P. graveolens, P. radens and P. tomentosum. p-Cymene was the principle component (37.6-45.4%) in both samples of P. panduriforme. It was also the major compound (54.9%) in P. quercifolium (provenance WSBG) followed by lesser amounts of viridiflorol (13.0%) and spathulenol (5.9%). Pelargonium quercifolium (provenance SBG) and P. capitatum (provenance WSBG) were characterized by a high viridiflorol content (24.0-36.6%). Pelargonium glutinosum (provenance SBG) was closely associated with the latter species; its oil was typified by oxygenated sesquiterpenes namely caryophyllene oxide (6.3%), spathulenol (6.9%) and viridiflorol (8.9%). Citronellyl formate (31.1%), citronellol (9.9%) and furopelargone B (6.1%) were most abundant in P. capitatum (provenance Strand). Pelargonium hispidum oil (provenance SBG) was characterized by decanoic acid (47.0%) and 2-decenoic acid (31.3%). Pelargonium scabrum produced an oil rich in 14-hydroxy-β-caryophyllene (27.9%). Pelargonium scabrum was associated with P. betulinum (provenance NBG) which was characterized by the oxygenated sesquiterpene T-cadinol (18.9%). [ABSTRACT FROM AUTHOR]