scholarly journals Photostabilization of Phenoxyacetic Acid Herbicides MCPA and Mecoprop by Hydroxypropyl-β-cyclodextrin

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Cátia Costa ◽  
Sílvia Maia ◽  
Paulo Silva ◽  
Jorge Garrido ◽  
Fernanda Borges ◽  
...  
Keyword(s):  
Inclusion Complexes ◽  
Aqueous Media ◽  
Structural Features ◽  
Positive Influence ◽  
Solar Irradiation ◽  
Phenoxyacetic Acid ◽  
Photochemical Degradation ◽  
Radical Intermediate ◽  
Versatile Tool ◽  
Acid Herbicides

New strategies to reduce the environmental and economic costs of pesticides use are currently under study. Microencapsulation has been used as a versatile tool for the production of controlled release agricultural formulations. In this study, the photochemical degradation of the herbicides MCPA and mecoprop has been investigated in different aqueous media such as ultrapure and river water under simulated solar irradiation. To explore the possibility of introducing cyclodextrins in the herbicide formulations, the photodegradation study of the inclusion complexes of MCPA and mecoprop with (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD) was also performed. The half-lives of MCPA and mecoprop inclusion complexes were increased approximately by a factor of three related to the free molecules. Additionally, it has been shown that the photodegradation of MCPA and mecoprop is influenced by their structural features. The additional methyl group existing in mecoprop molecular structure has a positive influence on the stabilization of the radical intermediate formed in the first stage of photodegradation of both herbicides. The results found indicated that MCPA and mecoprop form inclusion complexes with HP-β-CD showing higher photostability compared to free herbicides indicating that HP-β-CD may serve as ingredient in these herbicide formulations.

scholarly journals Influence of Hydroxypropyl-β-Cyclodextrin on the Photostability of Fungicide Pyrimethanil

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Carlos Fernandes ◽  
Igor Encarnação ◽  
Alexandra Gaspar ◽  
Jorge Garrido ◽  
Fernanda Borges ◽  
...  
Keyword(s):  
Inclusion Complex ◽  
Aqueous Media ◽  
Aqueous Solubility ◽  
Solar Irradiation ◽  
Proton Nuclear Magnetic Resonance ◽  
Resonance Spectroscopy ◽  
Photochemical Degradation ◽  
Pesticide Application ◽  
Negative Effects ◽  
Simulated Solar Irradiation

Pesticides continue to play an important role in pest management. However, the intensive pesticide application has triggered several environment negative effects that cannot be disregarded. In this study, the inclusion complex of pyrimethanil with HP-β-CD has been prepared and characterized by proton nuclear magnetic resonance spectroscopy. The formation of the pyrimethanil/HP-β-CD inclusion complex increased the aqueous solubility of this fungicide around five times. To assess the influence of microencapsulation on the environmental photostability of the fungicide, the photochemical degradation of pyrimethanil and pyrimethanil/HP-β-CD inclusion complex has been investigated in different aqueous media such as ultrapure and river water under simulated solar irradiation. The studies allow concluding that pyrimethanil/HP-β-CD inclusion complex increases significantly the photostability of the fungicide in aqueous solutions, especially in natural water. Actually, the half-life of pyrimethanil/HP-β-CD inclusion complex was increased approximately by a factor of four when compared to the free fungicide. The overall results point out that pyrimethanil can be successfully encapsulated by HP-β-CD, a process that can improve its solubility and photostability properties.

scholarly journals Structure, thermal stability and magnetic behavior of Mn(II) complexes with phenoxyacetic acid herbicides

Polyhedron ◽  
2021 ◽  
pp. 115370
Author(s):  
Aleksandra Drzewiecka–Antonik ◽  
Wiesława Ferenc ◽  
Barbara Mirosław ◽  
Dariusz Osypiuk ◽  
Jan Sarzyński
Keyword(s):  
Thermal Stability ◽  
Magnetic Behavior ◽  
Phenoxyacetic Acid ◽  
Acid Herbicides

scholarly journals Preparation, characterization and featuring of an inclusion complex of nerol with β-cyclodextrin

2017 ◽  
Vol 5 (2) ◽  
pp. 195
Author(s):  
Mayara Coêlho ◽  
Herlane Da Silva ◽  
Muhammad Islam ◽  
Vicente Viana ◽  
Ana Amélia Melo-Cavalcante
Keyword(s):  
Inclusion Complex ◽  
Inclusion Complexes ◽  
Biological Activities ◽  
Aqueous Media ◽  
Limiting Factor ◽  
Thermo Gravimetric ◽  
Drug Molecules ◽  
Complex Cavity ◽  
Nonpolar Molecules ◽  
Low Solubility

Nerol is an acyclic type monoterpene with important biological activities. However, the low solubility in aqueous media is a limiting factor for its user. Cyclodextrins have been widely used in order to improve the solubility, stability and bioavailability of nonpolar molecules through the formation of inclusion complexes. Thus, the present study consists in the development of nerol inclusion complex in combination with the β-cyclodextrin (β-CD) followed by characterizing by thermal analysis and spectrophotometric absorption in the infrared (FTIR). The results suggest a complexation of nerol with β-CD having detours and changed the intensity of various bands. The thermo gravimetric curve of CI found to indicate an output of solvating water molecules from the complex cavity formed for replacement of drug molecules probably included. Thus, it is concluded a possibility to obtain inclusion complexes of nerol monoterpene with β-CD, which will increase its solubility and facilitate delivery process.

The adsorption of phenoxyacetic acid herbicides on goethite

1977 ◽  
Vol 61 (3) ◽  
pp. 545-553 ◽  
Author(s):  
B.V. Kavanagh ◽  
A.M. Posner ◽  
J.P. Quirk
Keyword(s):  
Phenoxyacetic Acid ◽  
Acid Herbicides

scholarly journals Photochemical Degradation of Micropollutants in Aqueous Media

2019 ◽  
Vol 272 ◽  
pp. 022080
Author(s):  
M S Khandarkhaeva ◽  
A A Batoeva ◽  
M R Sizykh ◽  
D G Aseev ◽  
O V Tsydenova
Keyword(s):  
Aqueous Media ◽  
Photochemical Degradation

scholarly journals Understanding Structural Features of Microbial Lipases–-An Overview

2008 ◽  
Vol 3 ◽  
pp. ACI.S551 ◽  
Author(s):  
John Geraldine Sandana Mala ◽  
Satoru Takeuchi
Keyword(s):  
Structural Analysis ◽  
Candida Rugosa ◽  
Structural Data ◽  
Data Bank ◽  
Candida Rugosa Lipase ◽  
Structural Features ◽  
X Ray Crystallography ◽  
Versatile Tool ◽  
Microbial Lipases

The structural elucidations of microbial lipases have been of prime interest since the 1980s. Knowledge of structural features plays an important role in designing and engineering lipases for specific purposes. Significant structural data have been presented for few microbial lipases, while, there is still a structure-deficit, that is, most lipase structures are yet to be resolved. A search for ‘lipase structure’ in the RCSB Protein Data Bank ( http://www.rcsb.org/pdb/ ) returns only 93 hits (as of September 2007) and, the NCBI database ( http://www.ncbi.nlm.nih.gov ) reports 89 lipase structures as compared to 14719 core nucleotide records. It is therefore worthwhile to consider investigations on the structural analysis of microbial lipases. This review is intended to provide a collection of resources on the instrumental, chemical and bioinformatics approaches for structure analyses. X-ray crystallography is a versatile tool for the structural biochemists and is been exploited till today. The chemical methods of recent interests include molecular modeling and combinatorial designs. Bioinformatics has surged striking interests in protein structural analysis with the advent of innumerable tools. Furthermore, a literature platform of the structural elucidations so far investigated has been presented with detailed descriptions as applicable to microbial lipases. A case study of Candida rugosa lipase (CRL) has also been discussed which highlights important structural features also common to most lipases. A general profile of lipase has been vividly described with an overview of lipase research reviewed in the past.

Sign in / Sign up

Export Citation Format

Share Document