scholarly journals Fumigant Toxicity in Myzus persicae Sulzer (Hemiptera: Aphididae): Controlled Release of (E)-anethole from Microspheres

Plants ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 124
Author(s):  
María J. Pascual-Villalobos ◽  
Manuel Cantó-Tejero ◽  
Pedro Guirao ◽  
María D. López

(E)-anethole is a phenylpropanoid that is the main compound found in the essential oils (EOs) of anise and fennel seeds, and either fumigant or direct contact activity of this compound has been demonstrated against aphids and stored product pests. In this work, solid microspheres were prepared by three methods—oil emulsion entrapment, spray-drying, and complexed with β-cyclodextrin. Fumigation activity of each microsphere preparation was tested against the green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), on pepper leaves. The best insecticidal activity was with (E)-anethole encapsulated in oil emulsion beads and introduced to aphids as a vapour over 24 h, with an LC50 of 0.415 μL/L compared to 0.336 μL/L of vapors from free (E)-anethole. Scanning electron microscopy of the beads revealed a compact surface with low porosity that produced a controlled release of the bioactive for more than 21 d, whilst most of the volatile was evaporated within two days if applied unformulated. Spray drying gave spherical particles with the greatest encapsulated yield (73%) of 6.15 g of (E)-anethole incorporated per 100 g of powder. Further work will be done on improving the formulation methods and testing the solid microspheres in all aphid stages scaling up the experimental assay. It is foreseen that nanotechnology will play a role in future developments of low risk plant protection products.

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2747
Author(s):  
Thomas Armand ◽  
Luâna Korn ◽  
Elodie Pichon ◽  
Marlène Souquet ◽  
Mélissandre Barbet ◽  
...  

Neonicotinoids are widely used to protect fields against aphid-borne viral diseases. The recent ban of these chemical compounds in the European Union has strongly impacted rapeseed and sugar beet growing practices. The poor sustainability of other insecticide families and the low efficiency of prophylactic methods to control aphid populations and pathogen introduction strengthen the need to characterize the efficiency of new plant protection products targeting aphids. In this study, the impact of Movento® (Bayer S.A.S., Leverkusen, Germany), a tetrameric acid derivative of spirotetramat, on Myzus persicae and on viral transmission was analyzed under different growing temperatures. The results show (i) the high efficiency of Movento® to protect rapeseed and sugar beet plants against the establishment of aphid colonies, (ii) the impact of temperature on the persistence of the Movento® aphicid properties and (iii) a decrease of approximately 10% of the viral transmission on treated plants. These observations suggest a beneficial effect of Movento® on the sanitary quality of treated crops by directly reducing primary infections and indirectly altering, through aphid mortality, secondary infections on which the spread of disease within field depends. These data constitute important elements for the future development of management strategies to protect crops against aphid-transmitted viruses.


Author(s):  
М. Б. Демчук ◽  
С. М. Гуреєва ◽  
Т. А. Грошовий

<p align="center"><strong>MODERN STATE OF CREATION, PRODUCTION AND RESEARCH OF DRUGS</strong></p><p align="center"><strong>M</strong><strong>.</strong><strong>B</strong><strong>. </strong><strong>Demchuk</strong><strong>, </strong><strong>S</strong><strong>.</strong><strong>M</strong><strong>. </strong><strong>Gureyeva</strong><strong><sup>1</sup></strong><strong>, </strong><strong>T</strong><strong>.</strong><strong>A</strong><strong>. </strong><strong>Hroshovyi</strong><strong></strong></p><p>TernopilStateMedicalUniversityby I.Ya. Horbachevsky</p><p><sup>1</sup>JSC “Farmak”</p><p><strong>Noti</strong><strong>ce</strong><strong> 19.</strong> The current state of development and research of multiple unit pellet systems.</p><p><strong>Summary: </strong>the literature on technological aspects of creations of pellets, features of compression pellet to obtain multiple unit pellet systems are summarized<strong>.</strong></p><p><strong>Keywords: </strong>pellets, methods of pellets, pellet pressing, multiple unit pellet systems.</p><p><strong>Introduction. </strong>Oral modified-release multiple-unit dosage forms have always been more effective therapeutic alternative to conventional or immediate release single-unit dosage forms. With regards to the final dosage form, the multiparticulates are usually formulated into single-unit dosage forms such as filling them into hard gelatin capsules or compressing them into tablets.</p><p>Pelletization is a technique that enables the formation of spherical beads or pellets with a mean diameter usually ranging from 0.5 to2.0 mm. These pellets can evantually be coated and very often used in controlled-release dosage forms. The use of pelletization and pellets leads to an improvement in the flowability, appearance and mixing properties, thus avoiding excessive dust and reducing segregation and, generally, eliminating undesirable properties and improving the physical or chemical properties of fine powders.</p><p>The pharmaceutical industry has developed a great interest in pelletization due to a variety of reasons:</p><p>– prevention of segregation of co-agglomerated components, resulting in an improvement of the uniformity of the content;</p><p>– prevention of dust formation;</p><p>– increasing bulk density and decreasing bulk volume;</p><p>– the defined shape and weight improves the appearance of the product;</p><p>– improvement of the handling properties, due to the free-flowing properties;</p><p>– improvement of the hardness and friability of pellets;</p><p>– controlled release application of pellets due to the ideal low surface area-to-volume ratio that provides an ideal shape for the application of film coatings.</p><p>Pellets are prepared by different techniques, such as extrusion and spheronisation, rotogranulation, solution, suspension or powder layering, spray-drying or spray-congealing.</p><p>Extrusion / spheronisation is a multistage process for obtaining pellets with uniform size from wet granulates (extrudates). The process is more labour-intensive and more expensive than the conventional wet-granulation technique, as its use should be limited only to the production of spherical pellets for controlled release of drugs.</p><p>The fluid-bed granulation consists in the spraying of a granulation solution onto the suspended particles, which then are dried rapidly in the hot air stream.</p><p>Rotogranulation is one of the most recent methods for the production of spheroids. The single-unit spheronizing system can be described using terms like centrifugal granulator, rotary fluidized-bed granulator, rotary fluid bed, rotary processor or rotor granulator.</p><p>Layering a suspension or a solution of a drug on a seed material (usually, a coarse crystal or nonpareil) can produce pellets that are uniform in size distribution and generally posess very good surphace morphology. These characteristics are especially desirable when pellets will be coated for the purpose of achieving a controlled release.</p><p>Dry powder layering is similar to the solution or suspension layering. Instead of these dispersions, the layering is performed using a drug powder.</p><p>Spray-drying represents another process with limited application in the development of pharmaceutical pelletized products, based on globulation. During spray-drying, a drug solution or suspension is sprayed, with or without excipients, into a hot-air stream, generating dry and highly spherical particles.</p><p>Spray-congealing (spray-chilling) is a technique similar to spray-drying. Spray-congealing is a process in which a drug is allowed to melt, disperse or dissolve in hot melts of gums, waxes, fatty acids or other melting solids. The dispersion is then sprayed into a stream of air and other gases with a temperature below the melting point of the formulation components.</p><p><strong>Conclusions.</strong> The basic requirements and approaches to development multiple unit pellet system, aspects and examples receipt of pellets and tablets based on them are described.</p>


Author(s):  
Lijun Zhou ◽  
Chao Li ◽  
Zhilin Zhang ◽  
Xiuxia Li ◽  
Yongcheng Dong ◽  
...  

AbstractThe green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), is an economically important cosmopolitan crop pest. Essential oils (EOs) are complex mixtures of secondary metabolites that exhibit a wide range of biological activities, including antioxidant, antimicrobial and anti-inflammatory activities. Monoterpenes, as the major constituents of EOs, are well known for having a range of biological activities. In this study, 9 monoterpenes were screened for fumigant toxicity against M. persicae, and the safety of monoterpenes to natural enemies was evaluated. The results of the bioassays indicated that 9 monoterpenes showed promising fumigant toxicity against M. persicae. Carvacrol was the most toxic compound based on the LC50 value, which was 1.566 mg/L, followed by bornyl acetate, terpinolene, and terpinyl acetate, which had higher toxicities towards aphids, with LC50 values of 2.648 mg/L, 2.759 mg/L, and 2.832 mg/L, respectively. In addition, the safety evaluation assays of carvacrol against Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) larvae (LC50 = 43.851 mg/L) did not affect nontarget invertebrates at concentrations that effectively controlled aphids. Carvacrol was safer than chlorpyrifos to natural enemy H. axyridis larvae (toxicity ratio = 28.00 > 2.93). These results identified several high-activity monoterpenes that can be used against this pest in greenhouses as botanical insecticides.


Author(s):  
R.A. Bagrov ◽  
◽  
V.I. Leunov

The mechanisms of transmission of potato viruses from plants to aphid vectors and from aphids to uninfected plants are described, including the example of the green peach aphid (Myzus persicae, GPA). Factors affecting the spreading of tuber necrosis and its manifestation on plants infected with potato leafroll virus (PLRV) are discussed. Recommendations for PLRV and GPA control in the field are given.


2020 ◽  
Vol 14 (3) ◽  
pp. 210-224
Author(s):  
Gayatri Patel ◽  
Bindu K.N. Yadav

Background: The purpose of this study was to formulate, characterize and in-vitro cytotoxicity of 5-Fluorouracil loaded controlled release nanoparticles for the treatment of skin cancer. The patents on nanoparticles (US8414926B1), (US61654404A), (WO2007150075A3) etc. helped in the selection polymers and method for the preparation of nanoparticles. Methods: In the present study nanoparticles were prepared by simple ionic gelation method using various concentrations of chitosan and sodium tripolyphosphate (TPP). Several process and formulation parameters were screened and optimized using 25-2 fractional factorial design. The prepared nanoparticles were evaluated for particle size, shape, charge, entrapment efficiency, crosslinking mechanism and drug release study. Results: The optimized 5-Fluorouracil loaded nanoparticle were found with particle size of of 320±2.1 nm, entrapment efficiency of 85.12%± 1.1% and Zeta potential of 29mv±1mv. Scanning electron microscopy and dynamic light scattering technique revealed spherical particles with uniform size. The invitro release profile showed controlled release up to 24 hr. Further study was carried using A375 basal cell carcinoma cell-line to elucidate the mechanism of its cytotoxicity by MTT assay. Conclusion: These results demonstrate that the possibility of delivering 5-Fluorouracil to skin with enhanced encapsulation efficiency indicating effectiveness of the formulation for treatment of basal cell carcinoma type of skin cancer.


Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 370
Author(s):  
Arkadiusz Artyszak ◽  
Dariusz Gozdowski ◽  
Alicja Siuda

Water shortage and drought are a growing problem in Europe. Therefore, effective methods for limiting its effects are necessary. At the same time, the “field to fork” strategy adopted by the European Commission aims to achieve a significant reduction in the use of plant protection products and fertilizers in the European Union. In an experiment conducted in 2018–2020, the effect of the method of foliar fertilization containing silicon and potassium on the yield and technological quality of sugar beet roots was assessed. The fertilizer was used in seven combinations, differing in the number and time of application. The best results were obtained by treating plants during drought stress. The better soil moisture for the plants, the smaller the pure sugar yield increase was observed. It is difficult to clearly state which combination of silicon and potassium foliar application is optimal, as their effects do not differ greatly.


Author(s):  
Gavin Lewis ◽  
Axel Dinter ◽  
Charlotte Elston ◽  
Michael Thomas Marx ◽  
Christoph Julian Mayer ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document