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Background and Objectives: Due to adverse effects of pentavalent antimonial treatment of visceral leishmaniasis using herbal medicines has received a lot of attention. In this study, we evaluated inhibitory activity of Pelargonium roseum essential oil on growth of Leishmania infantum promastigotes, and compared it with that of Glucantime. Methods: Inhibitory effects of different concentrations (1, 2.5, 5, 10, 25, 50 and 100 μL/ml) of P. roseum essential oil on the growth of L. infantum promastigotes were studied by MTT assay after 24 and 48 hours. All the data were analyzed by one-way analysis of variance. The effect of the essential oil was later compared with that of standard dose of Glucantime. Results: After 24 hours, different concentrations of the essential oil had no significant inhibitory effect on promastigotes of L. infantum. After 48 hours, all concentrations except for 1μL/ml showed significant anti-leishmanial activity. In addition, the lowest concentration that had significant inhibitory effect on L. infantum promastigote was 5 μL/ml. Conclusion: The essential oil of P. roseum has favorable inhibitory activity on the growth of L. infantum promastigotes after 48 hours. This indicates the therapeutic potential of this plant for treatment of leishmaniasis. [ABSTRACT FROM AUTHOR]

The mucous layer that covers the intestinal absorptive surface acts as a diffusive barrier between the intestinal lumen and absorptive cells. In this report, we studied the effect of changing the body weight, intestinal mucin2 gene expression and number of goblet cells by feeding 1-d-old chicks a control diet or a diet containing either an antibiotic growth promoter or dietary essential oils (clove, coriondrum, artemisia sieberi and myrtle) at three levels. On day 42 of age two birds from each replicate were randomly selected, weight and then slaughtered. Goblet cell number was analyzed from each preparation. Mucin2 mRNA expression in intestinal jejunum tissue was quantitated using real-time quantitative PCR. We found that body weights were increased in chicks fed antibiotic and essential oil treatments compared with those fed control diet at 42 days of age (P<0.01). Dietary essential oils increased the mucin2 gene expression in the jejunum compared with the control treatment (P<0.05). In dietary essential oils fed chicks, the number of goblet cells was decreased in the small intestine compared with control treatment (P<0.05). These results indicate that essential oils altered processes of mucin biosynthesis via changes in the intestinal mucin2 gene expression and number of goblet cells. These modifications in mucin dynamics influence gut function and health and may change nutrient uptake. [ABSTRACT FROM AUTHOR]

Essential oils from three species of plants comprising three plant families were obtained by Clevenger-type water distillation. The major compounds in these essential oils were identified with GC-MS and their insecticidal activity against adult cotton aphid,Aphis gossypiiGlover tested with dosage-mortality bioassays. We examined mortality only for viviparous adults because sizeable aphid populations on cucumber (Cucurbitaceae) hosts are largely produced by these wingless, parthenogenic females. Three of the oils were directly applied to aphid females in randomised blocks at 25 ± 2 °C and 60 ± 5% R.H. and under a L16:D8 photoperiod. Essential oils were mixed with a non-toxic emulsifying agent, Tween 80. Results show adverse contact effects of essential oils studied in the control of cotton aphid. Probit analysis and LC50at concentrations at different exposures showed aphids were incapacitated and killed by aliphatic aldehydes, phenols and monocyclic terpenes contained inAzadirachta indica, Eucalyptus camaldulensisandLaurus nobilis. LC50on cotton aphid, for azadirachtin eucalyptus and laurel essential oils were respectively 5389, 9515 and 13730 ppm. In the current study, efficacy in respect to the contact toxicity (LC50) followed the order:A. indica > E. camaldulensis > L. nobilisafter 24 h treatment. Our results show quantitative and qualitative differences in the chemical composition and insecticidal activities of our essential oils. All oils became insect toxic as concentration increased. According to the results, essential oils of all the three plants have the potential to be employed in the pest management programmes that can be used in protection of greenhouse conditions against cotton aphid. [ABSTRACT FROM PUBLISHER]

The cotton aphid,Aphis gossypiiGlover (Hem: Aphididae), is one of the most injurious pests of fruits, vegetables and ornamental plants worldwide, both outdoor and indoor. Currently, the main method of control of this pest is through application of pesticides which is mostly accompanied by the resistance of the pest against pesticide(s). The resurgence of resistant aphid populations brings about further contamination of foodstuff and environment. Essential oils obtained from the aerial parts of plants may have the potential to be an alternative to synthetic pesticides, since they have been demonstrated to possess a wide range of bioactivities against insects and mites. So, the aim of the current study was to investigate the effect of essential oils extracted from three different plants namely:Azadirachta indicaAdr. Juss. (Meliaceae),Eucalyptus camaldulensisDehn. (Myrtaceae) andLaurus nobilisL. (Lauraceae) againstA. gossypii. The LC50values of essential oils ofA. indica,E. camaldulensisandL. nobilisagainstA. gossypiiwere 1.96, 2.28 and 3.16 μl L−1air, respectively. This shows thatA. indicapossesses the highest lethal activity whereasL. nobilisthe lowest. These data suggest that essential oils of all the three plants have the potential to be employed in the pest management programmes designed for a control ofA. gossypiiunder greenhouse conditions. [ABSTRACT FROM PUBLISHER]