scholarly journals Identification and evaluation of (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol as the trail following pheromone on Microcerotermes exiguus (Isoptera:Termitidae)

2017 ◽  
Vol 66 (1) ◽  
pp. 303
Author(s):  
Giuseppe Lubes ◽  
Aivle Cabrera
Keyword(s):  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Whole Body ◽  
Fragmentation Pattern ◽  
Control Methods ◽  
Trail Following ◽  
Sternal Glands ◽  
Main Component ◽  
Behavioral Assays ◽  
As Solid Phase

Trail-following pheromone is one of the most important semiochemical in termites. This pheromone is responsible for the recruitment of individuals from the colony to perform different tasks. The aim of this work was to isolate and identify the trail-following pheromone of Microcerotermes exiguus (Isoptera: Termitidae), a typical termite from the Neotropic, that is considered pest in some crops. Subterranean nest of M. exiguus were collected with a shovel in Caracas, Venezuela in 2010. Different chemical micro-reactions combined with chromatographic analysis of solvent extracts, as well as solid phase microextraction analyses (SPME) were applied to termite sternal glands; besides, some behavioral biossays were undertaken. A peak in the chromatograms from extracts (retention index: 1483), presented a fragmentation pattern with m/z ions: 41; 55; 67; 79; 91; 105; 119; 135; 142; 180, this result alongside behavioral assays allowed us to conclude that (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol (DTOH) acts as the main component of the trail following pheromone. The estimated optimum concentration for termite recruitment and orientation was around 1 pg/cm, being statistically comparable to the value on trails marked with whole body extracts at concentration of 1 worker/cm. The period of time that this compound takes to recruit other colony members is 13.67 ± 5.76 s and lasts up to two hours. Both analytical and behavioral results provided better understanding on the chemical communication of M. exiguus. This information could be used for the future development of newer pest control methods. 

scholarly journals Ionic Liquid-modified NiTi Composite Nanosheets Coating for Efficient Solid Phase Microextraction of Octadecylamine in Brine

2019 ◽  
pp. 1-8
Author(s):  
Huiju Wang
Keyword(s):  
Ionic Liquid ◽  
Solid Phase Microextraction ◽  
Extraction Efficiency ◽  
Solid Phase ◽  
Correlation Coefficients ◽  
Fiber Coating ◽  
Relative Standard ◽  
Optimized Conditions ◽  
As Solid Phase

Ionic     liquid (IL), 1-dodecyl-3-methylimidazolium-3-hydroxy-2-naphthoate (C12mimHNC) was synthesized and coated on the surface of NiTi as solid phase microextractiom fiber coating for determination the octadecylamine in brine. Prior to modification with IL, the NiTi was hydrothermally treated for in-situ growth of titanium and nickel oxide composite nanosheets (TiO2/NiOCNSs). The TiO2/NiOCNSs fibers coating was oriented  around the NiTi  substrate and  presented  double-faced  open  access  sites,  which provided a desired support framework for the further modification with IL. The extraction performance of C12mimHNC-TiO2/NiOCNSs fiber coating was evaluated for       detection of octadecylamine (ODA) coupled to HPLC with UV detection. As a result, the C12mimHNC-TiO2/NiOCNSs fiber coating illustrated excellent adsorption and extraction capability for ODA. The main factors affected extraction efficiency were optimized. Under the optimized  conditions,  good  linearity was  obtained  in  the  range of  1-150  µg/L with correlation  coefficients  (r2)  above  0.985.  Limits of detection (LODs) for  the  developed method was 0.280 µg/L. The proposed method was first applied to extract the ODA in brine samples. Relative recoveries varied from 78.3% to 96.5% at spiking level of 15µg/L and 30 µg/L with the relative standard deviations (RSDs) less than 8.7%.

Tacoma controls tastes and odours with ozone

2007 ◽  
Vol 55 (5) ◽  
pp. 137-144 ◽  
Author(s):  
M. Carlson ◽  
T. Chen ◽  
C. McMeen ◽  
I.H. Suffet ◽  
M. Zhang
Keyword(s):  
Hydrogen Peroxide ◽  
Analytical Methods ◽  
Contact Time ◽  
Solid Phase Microextraction ◽  
Solid Phase ◽  
First Order ◽  
Ozone Dose ◽  
Gorge Reservoir ◽  
Flavour Profile ◽  
As Solid Phase

The study is focussed on the conditions that would provide the best ozone oxidation to decrease the taste and odour of the water from Eagle Gorge Reservoir. This study incorporated advanced analytical methods, such as solid phase microextraction (SPME) and flavour profile analyses (FPA), to evaluate the best method for improving taste and odour. The study developed first-order relationships between ozone dose and the oxidation of several taste and odour compounds. The results focussed on the importance and interactions between ozone dose, pH, hydrogen peroxide and contact time.

scholarly journals Method Validation and Evaluation of Safrole Persistence in Cowpea Beans Using Headspace Solid-Phase Microextraction and Gas Chromatography

Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6914
Author(s):  
Maria Suely Siqueira Ferraz ◽  
Lêda Rita D’Antonino Faroni ◽  
Fernanda Fernandes Heleno ◽  
Adalberto Hipólito de Sousa ◽  
Lucas Henrique Figueiredo Prates ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Solid Phase Microextraction ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Agricultural Pests ◽  
Limit Of Quantification ◽  
Headspace Solid Phase Microextraction ◽  
Flame Ionization ◽  
Stored Grains ◽  
Main Component

Bioinsecticides are regarded as important alternatives for controlling agricultural pests. However, few studies have determined the persistence of these compounds in stored grains. This study aimed at optimizing and validating a fast and effective method for extraction and quantification of residues of safrole (the main component of Piper hispidinervum essential oil) in cowpea beans. It also sought to assess the persistence of this substance in the grains treated by contact and fumigation. The proposed method used headspace solid-phase microextraction (HS-SPME) and gas chromatography with a flame ionization detector (GC/FID). Factors such as temperature, extraction time and type of fiber were assessed to maximize the performance of the extraction technique. The performance of the method was appraised via the parameters selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy. The LOD and LOQ of safrole were 0.0057 and 0.019 μg kg−1, respectively and the determination coefficient (R2) was >0.99. The relative recovery ranged from 99.26 to 104.85, with a coefficient of variation <15%. The validated method was applied to assess the persistence of safrole residue in grains, where concentrations ranged from 1.095 to 0.052 µg kg−1 (contact) and from 2.16 to 0.12 µg kg −1 (fumigation). The levels measured up from the fifth day represented less than 1% of the initial concentration, proving that safrole have low persistence in cowpea beans, thus being safe for bioinsecticide use. Thus, this work is relevant not only for the extraction method developed, but also for the possible use of a natural insecticide in pest management in stored grains.

Sign in / Sign up

Export Citation Format

Share Document