Year-end Sale % OFF 
Abstract
This study aimed to evaluate the larvicidal activity of essential oil microparticles (EO) of Melissa officinalis L. against Aedes aegypti. The leaves of M. officinalis were collected in the municipality of São José de Ribamar, Maranhão, Brazil, later dried, crushed and ground. 90g of the dried leaves were used to obtain the EO by the hydrodistillation method. For the synthesis of microencapsulated EO, 60g of sodium alginate (2.5% m/v) was added to the mixture of 15g of Tween 20 with 6g of EO. The mixture was homogenized and drips over CaCl2 5% m/v solution for the hardening of particles via crosslinking. The microparticles were washed with distilled water in filter and dried at 35ºC/24h and 15 days at tamb (30ºC). The eggs of Aedes aegypti were collected at the Federal University of Maranhão by the ovitrampas method. The larvae that hatched were fed until they reached the fourth instar. Groups of larvae (n=20) were submitted to solutions of EO and microparticles of 10-90 mg/L . After 24 h, live and dead larvae were counted and LC50 was calculated by the Reed&Muench method, using Cheng's criterion for classification of active potential. All larvae presented mortality in all concentrations tested. The LC50 obtained for the EO was 40.60 mg/L and for the microparticles 22.10 mg/L, both classified as active according to the adopted criterion, but it is observed that the microparticles increased the larvicidal potential of the EO. Through the results obtained, it is concluded that the microparticles formulated with the EO proved to be efficient in the face of the larvae of Aedes aegypti, being interesting and important in controlling and combating the mosquito that transmits dengue.
Highlights
Microencapsulation is a technique used as a tool for protection and modulation of the release of substances
2.2 Obtaining oils For the extraction of essential oil microparticles (EO) M. officinalis, the hydrodistillation technique was used with a glass Clevenger extractor coupled to a round-bottomed balloon packed in an electric blanket as a heat generating source. 90g of the dried peels of M. officinalis were used adding distilled water (1:10)
3.1 Chemical constituents We identified 15 components in the EO sample of M. officinalis, and the majority constituents were: geranial (23.15%)
Summary
Microencapsulation is a technique used as a tool for protection and modulation of the release of substances. Active substances of plant origin, such as monoterpenes and their complex mixtures (essential oils) have a variety of properties among which are of biological interest, such as potential larvicides in the control of arboviruses vectors. Some limitations related to the stability of these substances and their mixtures can be observed in the direct use of a general form (rapid volatilization, oxidation of the chemical constituents of the oil, among others). These limitations can be addressed with the use of carrier systems, such as microcapsules in the control of arbovirus vectors (Gonsalves et al, 2009). The best method of control is prevention, attacking its urban vector (Govindarajan, 2013)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
