Comparative efficacy of essential oils of three aromatic plants as alternatives in the control of Phytophthora spp., agent of cocoa tree (Theobroma cacao L.) black pod disease in Côte d'Ivoire

This study aimed at comparing the efficacy of essential oils from three aromatic plants species (Cymbopogon citratus, Eucalyptus citriodora and Ocimum gratissimum) in vitro and in vivo against two Phytophthora strains (Phytophthora palmivora and P. megakarya) in a view to developing new biofongicides for the control of cocoa tree black pod disease. Essential oils were applied at four different concentrations (0.5; 1; 3 and 5 mL/L) in vitro and in vivo on leaf discs of three cocoa clones (NA32, PA150 and SCA6) whichsusceptibility is known. As results, all three essential oils significantly (p˂ 0.05) reduced in vitro mycelial growth of both Phytophthora strains and also reduced the leaf susceptibility to these strains. Inhibition rates in vitro of Phytophthora strains mycelial growth ranged from 83.80 to 100% for the essential oils of Cymbopogon citratus and Ocimum gratissimum species and from 17.7 to 100% for which of Eucalyptus citriodora species. In the biotests, the leaf susceptibility index of clone NA32 (susceptible) was reduced from 3.14 to 0.40. This correspond to reduction rates ranged from 64.87 to 86.70% of leaf susceptibility to both Phytophthora strains. Essential oils (HS and HO) from Cymbopogon citratus and Ocimum gratissimum species were most effective than which from Eucalyptus citriodora species. However, all three essential oils revealed antifungal properties. Therefore, they could be recommended as biofungicides for a sustainable control of cocoa tree black pod disease in Côte d'Ivoire.

Ellagic Acid (EA), a Tannin Was Isolated From Eucalyptus Citriodora Leaves and Its Anti-Inflammatory Activity

A tannin, EA ( 1 ), and other nine non-tannins compounds, gallic acid ( 2 ), quercetin ( 3 ), myricetin ( 4 ), 3-O-methylellagic acid 4'-O-α-L-rhamnopyranoside ( 5 ), quercetin-3-O-β-D-galactopyranoside ( 6 ), kaempferol-3-O-β-D-glucoside ( 7 ), quercetin 3-O-β-D-glucuronide ( 8 ), quercetin-3-O-rutinoside ( 9 ), 3,3',4-tri-O-methylellagic acid-4'-O-β-D-glucopyranosyl ( 10 ) were isolated from a valuable medicinal plant, Eucalyptus citriodora . Structural identification of these compounds was conducted using 1 H NMR and 13 C NMR spectroscopy and comparing their spectral data with those previously reported in literatures. The anti-inflammatory effects of EA were evaluated in ethanol-induced acute gastric ulcer mice models in our study. The result demonstrated that the intragastric administration of EA significantly prevented the gastric ulceration caused by ethanol treatments. Especially, the gastric tissue in the middle dose EA (100 mg/kg) showed few ulcerations with only slight focal congestion which indicated that it has a significant protective effect on gastric ulcer by increasing the IL-10 and PGE 2 levels, and reducing the IL-6, TNF-α, GAS and COX-2 levels. In addition, the middle-dose EA has no adverse effect on liver and kidney. These findings imply that EA exerts gastroprotective effects by means of its anti-inflammatory effects and may be a potential drug for anti-ulcer treatment.

USE OF ESSENTIAL OILS IN ONYCHOMYCOSIS: AN INTEGRATIVE REVIEW

Objective: identify in the literature how essential oils are used in onychomycosis. Methods: integrative review with searches performed in the MEDLINE/PubMed, Web of Science, Cochrane, SCOPUS and BVS databases, with 13 studies analyzed. Results: the use of essential oils Melaleuca alternifolia, Lavandula angustifolia, Eucalyptus citriodora and Foeniculum vulgare are effective and bring benefits in the treatment of onychomycosis, as they inhibit the mycelial growth of the nail fungus. Therefore, health professionals involved in the care of people with onychomycosis must keep themselves updated on such treatment alternatives and, consequently, on improving the care provided to these patients. Conclusion: the antifungal efficacy of a variety of oils has been proven with different forms of presentation and possible associations. However, the level of evidence presented was low, which justifies the need for more robust studies on the subject.

Caracterização da composição e estrutura da fauna epígea em monocultivos de café e eucalipto, no Norte do Espírito Santo

O objetivo deste estudo foi caracterizar e comparar a abundância e diversidade da fauna epígea entre diferentes sistemas agrícolas, no município de Sooretama, ES. Foram selecionadas duas áreas a saber: monocultivo de café (Coffea conephora) e monocultivo de eucalipto (Eucalyptus citriodora), ambas com 5 anos. A amostragem da fauna epígea foi realizada com o auxílio de armadilhas de queda do tipo pitfall traps. Em cada área, foram instaladas 10 armadilhas, que permaneceram no campo por 7 dias. A partir da identificação e quantificação dos organismos, foram calculados o número de indivíduos por armadilha ao dia, riqueza média e riqueza total, e os índices de diversidade de Shannon, uniformidade de Pielou e dominância de Simpson. Os grupos taxonômicos foram ainda classificados quanto à funcionalidade. No plantio de café, o grupo com maior atividade foi Isopoda, com 52,41 % de indivíduos coletados, seguido pelo grupo Formicidae com 18,46 %. Na área de plantio de eucalipto o grupo taxonômico de maior atividade foi o Formicidae com 83,34 % de indivíduos coletados. O plantio de café favoreceu a atividade e diversidade da fauna, sendo verificada a maior abundância de indivíduos, riqueza de grupos e maior diversidade nessa área. A análise da funcionalidade mostrou que o plantio de café promoveu melhores condições para o grupo saprófago Isopoda e o plantio de eucalipto o grupo social (Formicidae).