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Chemical composition, leaf trichome types and biological activities of the essential oils of four related salvia species indigenous to Southern Africa / Guy P. P. Kamatou 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. 72-79 Titre : Chemical composition, leaf trichome types and biological activities of the essential oils of four related salvia species indigenous to Southern Africa Type de document : texte imprimé Auteurs : Guy P. P. Kamatou, Auteur ; Robyn L. Van Zyl, Auteur ; Sandy F. Van Vuuren, Auteur Année de publication : 2013 Article en page(s) : pp. 72-79 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Salvia  africana-caerulea  Salvia  africana-lutea  Salvia  chamelaeagnea  Salvia  lanceolata  Lamiaceae  Trichomes  Biological  activities  Essential  oil  α-pinene  Myrcene  1,8-cineole  Spathulenol  Caryophyllene-oxide Résumé : The essential oils from fresh aerial parts of four Salvia species indigenous to southern Africa were obtained by hydrodistillation and analyzed by GC and GC/MS. Quantitative rather than qualitative differences in oil composition were observed. Forty-three compounds in each species accounting for 78% (S. africana-caerulea), 78% (S. africana-lutea), 96% (S. chamelaeagnea) and 81% (S. lanceolata) of the total composition were identified. Salvia africana-caerulea and S. lanceolata were dominated by oxygen-containing sesquiterpenes (59% and 48%, respectively). Oxygen-containing monoterpenes dominated in S. chanuslaeagnea (43%), while monoterpene hydrocarbons (36%) were abundant in S. africana-lutea. Scanning electron and light microscopy of the indumentum of the leaves revealed the presence of glandular and non-glandular trichomes. Non-glandular point-shaped trichomes composed of two or three cells are common in all four species and two types of glandular trichomes were noted: peltate trichomes, with up to 16 head cells and a capitate type varying in the number of cells comprising the head and stalk. The oils were evaluated against two Gram-positive and two Gram-negative bacterial strains using the microdilution method and the MIC values ranged from 0.8 to 32 mg/mL. The oils exhibited antiplasmodial (5 < IC50 < 9 pg/mL) and anti-inflammatory (43 < ICc0 < 77 pg/mL) activity as determined by the [3H]-hypoxanthine radiometric and 5-lipoxygenase methods, respectively. Compared to other naturally derived antiplasmodial compounds (e.g. quinine) the oils are more toxic to human kidney epithelium cells (MTT method) with the ICc0 values ranging from 2-7 μg/mL. The oils exhibited poor antioxidant activity against the DPPH' radical at 100 pg/mL. ISSN : 1041-2905 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=18019087 [article] Chemical composition, leaf trichome types and biological activities of the essential oils of four related salvia species indigenous to Southern Africa [texte imprimé] / Guy P. P. Kamatou, Auteur ; Robyn L. Van Zyl, Auteur ; Sandy F. Van Vuuren, Auteur . - 2013 . - pp. 72-79. Génie Chimique Langues : Anglais (eng) in The journal of essential oil research > Vol. 18 N° Spécial (Juillet 2006) . - pp. 72-79 Mots-clés : Salvia  africana-caerulea  Salvia  africana-lutea  Salvia  chamelaeagnea  Salvia  lanceolata  Lamiaceae  Trichomes  Biological  activities  Essential  oil  α-pinene  Myrcene  1,8-cineole  Spathulenol  Caryophyllene-oxide Résumé : The essential oils from fresh aerial parts of four Salvia species indigenous to southern Africa were obtained by hydrodistillation and analyzed by GC and GC/MS. Quantitative rather than qualitative differences in oil composition were observed. Forty-three compounds in each species accounting for 78% (S. africana-caerulea), 78% (S. africana-lutea), 96% (S. chamelaeagnea) and 81% (S. lanceolata) of the total composition were identified. Salvia africana-caerulea and S. lanceolata were dominated by oxygen-containing sesquiterpenes (59% and 48%, respectively). Oxygen-containing monoterpenes dominated in S. chanuslaeagnea (43%), while monoterpene hydrocarbons (36%) were abundant in S. africana-lutea. Scanning electron and light microscopy of the indumentum of the leaves revealed the presence of glandular and non-glandular trichomes. Non-glandular point-shaped trichomes composed of two or three cells are common in all four species and two types of glandular trichomes were noted: peltate trichomes, with up to 16 head cells and a capitate type varying in the number of cells comprising the head and stalk. The oils were evaluated against two Gram-positive and two Gram-negative bacterial strains using the microdilution method and the MIC values ranged from 0.8 to 32 mg/mL. The oils exhibited antiplasmodial (5 < IC50 < 9 pg/mL) and anti-inflammatory (43 < ICc0 < 77 pg/mL) activity as determined by the [3H]-hypoxanthine radiometric and 5-lipoxygenase methods, respectively. Compared to other naturally derived antiplasmodial compounds (e.g. quinine) the oils are more toxic to human kidney epithelium cells (MTT method) with the ICc0 values ranging from 2-7 μg/mL. The oils exhibited poor antioxidant activity against the DPPH' radical at 100 pg/mL. ISSN : 1041-2905 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=18019087

The biological activities of 20 nature identical essential oil constituents / Robyn L. Van Zyl 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. 129-133 Titre : The biological activities of 20 nature identical essential oil constituents Type de document : texte imprimé Auteurs : Robyn L. Van Zyl, Auteur ; Sammy T. Seatlholo, Auteur ; Sandy F. Van Vuuren, Auteur Année de publication : 2013 Article en page(s) : pp. 129-133 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Nature  identical  essential  oil  constituent  (-)-α-bisabolol  Geraniol  (±)-linalool  (E-  &  Z-)-(±)-nerolidol  (-)-citronellal  Trans-geranyl  acetate  Linalyl  acetate  (±)-α+β-thujone  (+)-carvone  (-)-fenchone  (-)-menthone  (-)-pulegone  Carvacrol  Eugenol  (+)-α-pinene  (+)-β-pinene  γ-terpinene  p-cymene  1,8-cineole  (+)-limonene  Antimicrobial  activity  Antimalarial  activity  Antioxidant  activity  Toxicity Résumé : Twenty nature identical essential oil constituents from seven structural groups were tested for antimalarial, antimicrobial, antioxidant and toxicity properties. The compounds displayed antimalarial activity (IC50 values ranging from 0.9 to 1528.8 μM) with varying toxicity (IC50 values ranging from 5.5 to 1358.4 pM). The data indicates that (-)-pulegone, (E- & Z-)-(±)-nerolidol, linalyl acetate and (+)-α-pinene have the most potent antimalaial activity. Carvacrol (MIC values ranging from <1.66 to 13.3 mM) followed by geraniol (MIC values: 19.5-51.9 mM) displayed the broadest spectrum of antimicrobial activity. The least toxic of the tested compounds, eugenol, was the only compound with antioxidant activity comparable to ascorbic acid. The results demonstrate that the 20 compounds individually display variable biological activity, although further research is required to determine how they may interact when combined. ISSN : 1041-2905 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=18019096 [article] The biological activities of 20 nature identical essential oil constituents [texte imprimé] / Robyn L. Van Zyl, Auteur ; Sammy T. Seatlholo, Auteur ; Sandy F. Van Vuuren, Auteur . - 2013 . - pp. 129-133. Génie Chimique Langues : Anglais (eng) in The journal of essential oil research > Vol. 18 N° Spécial (Juillet 2006) . - pp. 129-133 Mots-clés : Nature  identical  essential  oil  constituent  (-)-α-bisabolol  Geraniol  (±)-linalool  (E-  &  Z-)-(±)-nerolidol  (-)-citronellal  Trans-geranyl  acetate  Linalyl  acetate  (±)-α+β-thujone  (+)-carvone  (-)-fenchone  (-)-menthone  (-)-pulegone  Carvacrol  Eugenol  (+)-α-pinene  (+)-β-pinene  γ-terpinene  p-cymene  1,8-cineole  (+)-limonene  Antimicrobial  activity  Antimalarial  activity  Antioxidant  activity  Toxicity Résumé : Twenty nature identical essential oil constituents from seven structural groups were tested for antimalarial, antimicrobial, antioxidant and toxicity properties. The compounds displayed antimalarial activity (IC50 values ranging from 0.9 to 1528.8 μM) with varying toxicity (IC50 values ranging from 5.5 to 1358.4 pM). The data indicates that (-)-pulegone, (E- & Z-)-(±)-nerolidol, linalyl acetate and (+)-α-pinene have the most potent antimalaial activity. Carvacrol (MIC values ranging from <1.66 to 13.3 mM) followed by geraniol (MIC values: 19.5-51.9 mM) displayed the broadest spectrum of antimicrobial activity. The least toxic of the tested compounds, eugenol, was the only compound with antioxidant activity comparable to ascorbic acid. The results demonstrate that the 20 compounds individually display variable biological activity, although further research is required to determine how they may interact when combined. ISSN : 1041-2905 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=18019096