Biological effects of essential oils and extracts
Z. Kalvandi; J. Nazemi rafie; A. Sadeghi; A. Salimi; R. Kalvandi; M. Negahban
Abstract
Nowadays, the invention and application of agricultural pest control non-chemical methods is one of the important and practical ones in pest management programs in most societies of the world. Meanwhile, a large number of studies have been focused on bio-based pesticides. In this regard, new formulations ...
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Nowadays, the invention and application of agricultural pest control non-chemical methods is one of the important and practical ones in pest management programs in most societies of the world. Meanwhile, a large number of studies have been focused on bio-based pesticides. In this regard, new formulations of plant insecticides have been developed as a suitable alternative to artificial pesticides. In this research, respiratory and contact toxicity of pure and formulated Eucalyptus globulus Labill. essential oil and respiratory toxicity durability of its essential oil nanocapsules on adult insects of Tribolium confusum Herbest. (Col., Tenebrionidae) were investigated under laboratory conditions. According to the results, for respiratory toxicity, the pure and formulated essential oil LC50 at 24 h was obtained 46.39 and 1472 μl.l-1 of air, respectively. The formulated essential oil LT50 in three concentrations of LC25, LC50, and LC90 was determined 12.3, 10.39, and 0.36 days, respectively. The results also showed that the contact toxicity of formulated essential oil (LC50= 19030 μl.l-1) on this insect was much higher than the contact toxicity of pure one (LC50= 3770 μl.l-1). Therefore, due to the good stability of the formulated essential oil in respiratory toxicity and the excellent effect in contact toxicity, after additional tests, eucalyptus essential oil nanocapsules could be used in the management of this important pest.
M. Negahban; S. Moharramipour; M. Zandi; S.A. Hashemi
Abstract
Recent research has focused on insecticidal property of essential oil plants in biological control of insects. Controlled release by nanoencapsulated essential oil seems to be the best choice for increasing the efficiency and minimization of environmental damage. In this work, efficiency of nanoencapsulated ...
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Recent research has focused on insecticidal property of essential oil plants in biological control of insects. Controlled release by nanoencapsulated essential oil seems to be the best choice for increasing the efficiency and minimization of environmental damage. In this work, efficiency of nanoencapsulated essential oil of Artemisia sieberi Besser was tested on repellent activity of Plutella xylostella L.. Several concentrations were prepared and then third instars larvae were introduced into each treatment. Then, repellent activity was determined after 1, 3, 6, 12 and 24 h from commencement of exposure. Results showed that at 1.9 ppm the nanocapule of Artemisia oil was shown here to possess more repellent activity (80%) to P. xylustella compered to Artemisia oil (62%) before formulation after 24h. The repellent activity varied with application method and concentrations and exposure time. The results showed higher repellent rates in nanocapsule than in essential oil due to controlled-release formulations allowing smaller quantities of essential oil to be used more effectively over a given time interval. The reasons for nanocapsulating the essential oil have been to improve its stability to reduce side effects or to reduce dosing frequency and total dosing amount, to obtain better repellent activity, and for sustained (long-lasting) release. Therefore the nanocapsulation of A. sibeiri might provide a new method for the management of P. xylostella.
M. Negahban; S. Moharramipour; M. Zandi; S.A. Hashemi
Abstract
Controlled release by nanoencapsulated formulations allow the essential oil to be used more effectively over a given time interval, suitability to mode of application and minimization of environmental damage. In this work, efficiency of nanoencapsulated essential oil of Artemisia sieberi Besser was tested ...
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Controlled release by nanoencapsulated formulations allow the essential oil to be used more effectively over a given time interval, suitability to mode of application and minimization of environmental damage. In this work, efficiency of nanoencapsulated essential oil of Artemisia sieberi Besser was tested on nutritional indices of Plutella xylostella L. Several experiments were designed to measure the indices such as Relative Growth Rate (RGR), Relative Consumption Rate (RCR), Efficiency of Conversion of Ingested food (ECI), Efficiency of Conversion of Digested food (ECD), Approximate Digestibility (AD) and Feeding Deterrent Index (FDI). Treatments were evaluated by the method of leaf disk bioassay at 25 °C, 65±5% RH, and a photoperiod of 16:8 h (Light: Dark). Ten third-instar larvae were introduced into each treatment containing different concentrations of the essential oil. Then, ingested food and weight gained were measured after 24, 48 and 72 h intervals. Results showed that nanocapsule of A. sieberi oil was highly effective compared to control (A. sieberi oil), and significantly decreased the RGR ECI, ECD and AD. Moreover, findings indicated a post-ingestive toxicity of the essential oil using the nanoencapsulated formulation. As a result, this nanoencapsulated essential oil tested merits further study as potential insecticide for the control of P. xylostella.
M. Negahban; S. Moharramipour
Volume 23, Issue 2 , August 2007, , Pages 146-156
Abstract
In regard to the invasion of various food commodities by insects and harmful effects of chemical pesticides, essential oils are among the best known substances tested against stored product pests. Effects of essential oils from Artemisia sieberi Besser and Artemisia scoparia Waldst et Kit were tested ...
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In regard to the invasion of various food commodities by insects and harmful effects of chemical pesticides, essential oils are among the best known substances tested against stored product pests. Effects of essential oils from Artemisia sieberi Besser and Artemisia scoparia Waldst et Kit were tested against oviposition deterrence, egg hatching and first instar larvae of Callosobruchus maculatus F. at 27 ± 1˚C and 65 ± 5% R.H. under dark condition. For each essential oil, five replications were conducted. Increasing the essential oil concentrations resulted in increase if insecticidal activity of essential oils on eggs, first instar larvae and oviposition deterrence. At 0.14 mL/g food, the essential oils of A. sieberi and A. scoparia resulted in inhibition of oviposition of the insect. The maximum concentration of essential oils (2.86 mL/L air) caused 100% mortality of first instar larvae. Although, oviposition deterrence of A. scoparia was stronger than A. sieberi, however, ovicidal and larval mortality caused by both essential oils were not significantly different. LC50 values indicated that essential oil of A. scoparia with 1.11 and 1.06 mL/L air against eggs and first instar larvae do not have significant difference with A. sieberi. It was found that plant essential oils can be used as a safe pesticide or model for new synthetic pesticides to control stored pests.
M. Negahban; S. Moharramipour
Volume 23, Issue 1 , May 2007, , Pages 13-22
Abstract
Efficiency of essential oils from Artemisia sieberi Besserand A. scoparia Waldst et Kiton nutritional indices of Tribolium castaneum Herbst was tested in this study. Several experiments were designed to measure the indices such as relative growth rate (RGR), relative consumption rate (RCR), efficiency ...
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Efficiency of essential oils from Artemisia sieberi Besserand A. scoparia Waldst et Kiton nutritional indices of Tribolium castaneum Herbst was tested in this study. Several experiments were designed to measure the indices such as relative growth rate (RGR), relative consumption rate (RCR), efficiency of conversion of ingested food (ECI) and feeding deterrent index (FDI). Treatments were evaluated by the method of flour disk bioassay in the dark, at 27 ±1 0C and 65 ±5% R. H. Several concentrations of 0, 0.1, 0.5, 0.75, 1, 1.5 and 2 mL/disk were prepared from each essential oil and 10 adult insects were introduced into each treatment. Then, ingested food and weight gained were measured three days later. Results showed that A. sieberi oil was highly effective compared to A. scoparia, and significantly decreased the RGR and RCR. Moreover, in higher concentration (2 mL/disk), the ECI (9.81%) was significantly low. The A. sieberi oil was more effective on FDI than A. scoparia.
M. Negahban; S. Moharramipour
Volume 22, Issue 4 , February 2007, , Pages 293-302
Abstract
Repellent activity and persistence of essential oil of Artemisia sieberi Besser were investigated against three stored product insect speciesCallosobruchus maculatus F., Sitophilus oryzae L. and Tribolium Castaneum Herbst at 27±1˚C, 65 ± 5 %R. H under dark condition. In this study, dry ...
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Repellent activity and persistence of essential oil of Artemisia sieberi Besser were investigated against three stored product insect speciesCallosobruchus maculatus F., Sitophilus oryzae L. and Tribolium Castaneum Herbst at 27±1˚C, 65 ± 5 %R. H under dark condition. In this study, dry ground leaves were subjected to hydrodistillation using a modified clevenger-type apparatus. On the basis of the LT50s, C. maculatus was killed faster than S. oryzae and T. castaneum. Also, persistence or half-life time of the oil for C. maculatus was significantly longer than S. oryzae and T. castaneum. However, the essential oil was significantly more repellent to T. castaneum than S. oryzae and C. maculatus. These results demonstrated the efficacy of A. sieberi oil for applying in organic food protection.
