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Essential oil composition and in vitro biological activities of seven namibian species of Eriocephalus L. (Asteraceae) / Alvaro M. Viljoen in The journal of essential oil research, Vol. 18 N° Spécial (Juillet 2006) 

Public ISBD [article]  in The journal of essential oil research > Vol. 18 N° Spécial (Juillet 2006) . - pp. 124-128 Titre : Essential oil composition and in vitro biological activities of seven namibian species of Eriocephalus L. (Asteraceae) Type de document : texte imprimé Auteurs : Alvaro M. Viljoen, Auteur ; Elizabeth W. Njenga, Auteur ; Sandy F. Van Vuuren, Auteur Année de publication : 2013 Article en page(s) : pp. 124-128 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Eriocephalus  dinteri  Eriocephalus  ericoides  subsp.  ericoides  Eriocephalus  klinghardtensis  Eriocephalus  luederitzianus  Eriocephalus  merxmuelleri  Eriocephalus  pinnatus  Eriocephalus  scariosus  Asteraceae  Namibia  Essential  oil  composition  Chemotaxonomy  α-pinene  β-pinene  1,8-cineole  Santolina  alcohol  Linalool  Chrysanthenone  Camphor  α-longipinene  P-caryophyllene  Antimicrobial  activity  Anti-inflammatory  activity Résumé : The essential oil composition of seven Namibian Eriocephalus species (E. dinteri, E. ericoides subsp. ericoides, E. klinghardtensis, E. luederitzianus, E. merxmuelleri, E. pinnatus, E. scariosus) were determined by GC and GC/MS. The oils of E. ericoides subsp. ericoides (sample 1), E. merxmuelleri and E. scariosus were found to be rich in 1,8-cineole and camphor. Eriocephalus scariosus oil contained santolina alcohol (14.8%). The highest levels of camphor (38.4%) was found in E. dinteri oil. The major component of E. ericoides subsp. ericoides (sample 2) was linalool (10.4%). A chemical similarity between E. luederitzianus and E. klinghardtensis was observed which both accumulated high levels of α-pinene, β-pinene, p-cymene and γ-terpinene. Eriocephalus luederitzianus oil contained α-longipinene (10.3%) and β-caryophyllene (13.3%). The morphologically anomalous E. pinnatus was very different in oil composition when compared to the other taxa and is characterized by isoamyl 2-methylbutyrate (7.9%) and isoamyl valerate (6.5%). Antimicrobial disc diffusion assays and minimum inhibitory concentrations (MIC) were performed on all seven species. Good antifungal activity was noted for E. ericoides subsp. ericoides. Highest activities were noted for E. merxmuelleri against the Gram-positive test organisms and generally poor activity was noted against the Gram-negative test organisms for all species. The anti-inflammatory activity of the oils were assessed using the 5-lipoxygenase (5-LOX) enzyme and E. dinteri displayed the most promising inhibition (IC50 = 35 μg/ml). ISSN : 1041-2905 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=18019095 [article] Essential oil composition and in vitro biological activities of seven namibian species of Eriocephalus L. (Asteraceae) [texte imprimé] / Alvaro M. Viljoen, Auteur ; Elizabeth W. Njenga, Auteur ; Sandy F. Van Vuuren, Auteur . - 2013 . - pp. 124-128. Génie Chimique Langues : Anglais (eng) in The journal of essential oil research > Vol. 18 N° Spécial (Juillet 2006) . - pp. 124-128 Mots-clés : Eriocephalus  dinteri  Eriocephalus  ericoides  subsp.  ericoides  Eriocephalus  klinghardtensis  Eriocephalus  luederitzianus  Eriocephalus  merxmuelleri  Eriocephalus  pinnatus  Eriocephalus  scariosus  Asteraceae  Namibia  Essential  oil  composition  Chemotaxonomy  α-pinene  β-pinene  1,8-cineole  Santolina  alcohol  Linalool  Chrysanthenone  Camphor  α-longipinene  P-caryophyllene  Antimicrobial  activity  Anti-inflammatory  activity Résumé : The essential oil composition of seven Namibian Eriocephalus species (E. dinteri, E. ericoides subsp. ericoides, E. klinghardtensis, E. luederitzianus, E. merxmuelleri, E. pinnatus, E. scariosus) were determined by GC and GC/MS. The oils of E. ericoides subsp. ericoides (sample 1), E. merxmuelleri and E. scariosus were found to be rich in 1,8-cineole and camphor. Eriocephalus scariosus oil contained santolina alcohol (14.8%). The highest levels of camphor (38.4%) was found in E. dinteri oil. The major component of E. ericoides subsp. ericoides (sample 2) was linalool (10.4%). A chemical similarity between E. luederitzianus and E. klinghardtensis was observed which both accumulated high levels of α-pinene, β-pinene, p-cymene and γ-terpinene. Eriocephalus luederitzianus oil contained α-longipinene (10.3%) and β-caryophyllene (13.3%). The morphologically anomalous E. pinnatus was very different in oil composition when compared to the other taxa and is characterized by isoamyl 2-methylbutyrate (7.9%) and isoamyl valerate (6.5%). Antimicrobial disc diffusion assays and minimum inhibitory concentrations (MIC) were performed on all seven species. Good antifungal activity was noted for E. ericoides subsp. ericoides. Highest activities were noted for E. merxmuelleri against the Gram-positive test organisms and generally poor activity was noted against the Gram-negative test organisms for all species. The anti-inflammatory activity of the oils were assessed using the 5-lipoxygenase (5-LOX) enzyme and E. dinteri displayed the most promising inhibition (IC50 = 35 μg/ml). ISSN : 1041-2905 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=18019095