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Thymus essential oils. Chemical composition and in vitro antioxidant and antibacterial activities

Thymus essential oils. Chemical composition and in vitro antioxidant and antibacterial activities

In the last years, there is an increasing concern regarding the safety and potentially adverse effects of synthetic chemicals used for food preservation or in medicine. Therefore, many research groups were interested to the functional role of natural products especially plant extracts. Essential oils extracted by distillation from aromatic plants are appreciated for their bioactive efficacy as fungicides, bacteriostatics, antioxidants, and other biological activities.

In this study, the essential oils obtained from Thymus satureioides, Thymus vulgaris and Corydothymus capitatus by steam distillation were analyzed by gas chromatography coupled to mass spectrometry (GC-MS) in order to determine their chemical compositions. The results demonstrated that the major components of these essential oils are borneol, thymol and carvacrol respectively.

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DOORGAAN MET LEZEN

Evaluation of three essential oils as potential sources of botanical fungicides

In a previous  study, a microbioassay was developed and used  for  the  in vitro  screening of thirty  essential  oils  against  two  important  pathogens  of  citrus  (Penicillium  italicum  and  P. digitatum) and one  important pathogen of banana  (Colletotrichum musea). Three essential oils  (Cinnamomum  zeylanicum,  C.  verum  and  Eugenia  caryophyllus)  showed  a  good antifungal effect. The present study was thus undertaken to evaluate the  in vivo activity of these essential oils. To  this end,  fresh orange  fruits were disinfected and wounded before being  treated  at  the  wound  site  with  the  following  treatments:  distilled  water,  ethanol (1.5%), fungicide (0.4%), or with one of the essential oils (0.5, 1, 5, 10 and 20%). Two hours later, orange wounds were inoculated with a suspension (104 spores/ml) of P. italicum or P. digitatum.  Télécharger le résumé

Monographie de Roha, Hymenaea Verrucosa Gaertn

Ce grand arbre en forme de parasol, de 6 à 24 mètres de haut, à feuilles persistantes plates et couronnées, est originaire d’Afrique Australe, d’Afrique de l'Est, de Mascareignes et particulièrement de Madagascar. Les racines, le tronc et les fruits produisent une résine dure (le Copal) utilisée comme encens. Les fleurs sont jaunâtres et les fruits sont uniques. Ces derniers sont durs et parsemés sur l'extérieur par des bulles de résine. Ils sont vert rougeâtre à maturité, mais brunis-sent sur le terrain. Télécharger l'étude complète