Identification of Chemicals Associated Gambusia affinis (Cyprinodontiformes: Poeciliidae), and Their Effect on Oviposition Behavior of Culex tarsalis (Diptera: Culicidae) in the Laboratory

2021 ◽  
Author(s):  
Adena M Why ◽  
Dong-Hwan Choe ◽  
William E Walton
Keyword(s):  
Volatile Compounds ◽  
Oviposition Behavior ◽  
Dimethyl Disulfide ◽  
Ring Structure ◽  
Gambusia Affinis ◽  
Culex Tarsalis ◽  
Waste Products ◽  
Treated Water ◽  
Low Concentrations ◽  
Volatile Chemical Compounds

Abstract The western mosquitofish, Gambusia affinis (Baird & Girard), has been used worldwide for the control of larval mosquitoes for more than 100 yr. We found that the western encephalitis mosquito, Culex tarsalis Coquillett (Diptera: Culicidae), can detect the presence of G. affinis in oviposition sites based on associated chemicals, leading to a decrease in the number of egg rafts laid. Three volatile chemical compounds were identified in the headspace above the water where G. affinis had been held for 24 h. Oviposition bioassays conducted using standards of the volatile compounds identified (dimethyl disulfide [DMDS], dimethyl trisulfide [DMTS], and S-methyl methanethiosulphonate) found that females reduced oviposition only when low concentrations of DMTS were present, but this response was not consistent across all trials and concentrations tested. DMDS, DMTS, and S-methyl methanethiosulphonate are known bacterial metabolic waste products and may be the source of the compounds. Two nonvolatile compounds of interest were found to be present in the Gambusia-exudate water. After tasting Cx. tarsalis were deterred from ovipositing onto Gambusia-treated water from which the bacteria had been removed by filtration, indicating that the kairomone may consist of nonvolatile compound(s). One of the nonvolatile compounds isolated from the Gambusia-treated water has a benzene ring structure similar to that of cholesterol but the structure of the two nonvolatile deterrents remains to be fully characterized. Our research shows that three volatile compounds and two nonvolatile compounds are present in water associated with G. affinis (Poeciliidae: Gambusia) and affect the oviposition behavior of Cx. tarsalis in laboratory bioassays.

scholarly journals Oviposition Behavior of Culex tarsalis (Diptera: Culicidae) Responding to Semiochemicals Associated with the Western Mosquitofish, Gambusia affinis (Cyprinodontiformes: Poecilliidae)

2019 ◽  
Vol 57 (2) ◽  
pp. 343-352 ◽  
Author(s):  
Adena M Why ◽  
William E Walton
Keyword(s):  
Tap Water ◽  
Oviposition Behavior ◽  
Pond Water ◽  
Gambusia Affinis ◽  
Egg Laying ◽  
Culex Tarsalis ◽  
Mosquito Oviposition ◽  
Natural Density ◽  
Gravid Mosquitoes ◽  
Laboratory Bioassays

Abstract Considerable previous research has focused on predator-associated semiochemicals and how they affect mosquito oviposition behavior. However, most of this work has been done without taking into consideration either the natural density of the predators or how other semiochemicals in aquatic environments might affect the responses of gravid mosquitoes. The influence of mosquitofish density, source water (tap vs pond), presence of freshly laid egg rafts, and removal of a putative source of semiochemicals (bacteria) on oviposition by Culex tarsalis Coquillett (Diptera: Culicidae) was studied in laboratory bioassays. Culex tarsalis females were deterred from laying egg rafts on water that contained semiochemicals associated with Gambusia affinis (Baird & Girard), but this deterrence was not strongly associated with the density of fish used to condition aged tap water. The number of egg rafts laid onto Gambusia-exudate water made with either tap water (density < 1 fish per liter) or pond water was typically ≥ 50% of that onto water that did not house mosquitofish. Gravid mosquitoes tested individually did not reduce oviposition onto Gambusia-exudate water as compared to controls. Likewise, oviposition by females with ablated wings did not differ significantly between Gambusia-exudate water and controls. Oviposition onto filter-sterilized Gambusia-exudate water was reduced relative to unfiltered water, suggesting that semiochemicals deterring egg-laying were still present after bacteria were removed. Taken together, these findings suggest that the responses of gravid Cx. tarsalis to chemicals from habitats containing mosquitofish are complex and the origin of the semiochemicals present in the Gambusia-exudate water needs to be elucidated.

Experiments on high rate effluent filtration in the Netherlands

1998 ◽  
Vol 38 (3) ◽  
pp. 127-134
Author(s):  
Jaap H. J. M. van der Graaf ◽  
Arjen F. van Nieuwenhuijzen
Keyword(s):  
Wastewater Treatment ◽  
The Netherlands ◽  
Suspended Solids ◽  
Practical Experience ◽  
High Rate ◽  
Treated Water ◽  
Low Concentrations ◽  
Wastewater Treatment Effluent

As yet, filtration of wastewater treatment effluent has not been practised in the Netherlands. The main objections were the expected high costs. In order to gain practical experience an investigation programme studied the applicability and optimization of effluent filtration. Especially multi-layer filtration with the addition of ironchloride seemed to be very effective. Very low concentrations of suspended solids and phosphorus were achieved, even at high filtration rates (up to 30 m/h). This leads to an impressive reduction of expected costs, down to Dfl. 0.02/m3 (treated water).

scholarly journals Smells Like Teen Spirit—A Model to Generate Laundry-Associated Malodour In Vitro

2021 ◽  
Vol 9 (5) ◽  
pp. 974
Author(s):  
Marc-Kevin Zinn ◽  
Marco Singer ◽  
Dirk Bockmühl
Keyword(s):  
Volatile Compounds ◽  
Micrococcus Luteus ◽  
Dimethyl Disulfide ◽  
Bacterial Strains ◽  
Dimethyl Trisulfide ◽  
Model Based ◽  
Washing Machines ◽  
Staphylococcus Hominis

Although malodour formation on textiles and in washing machines has been reported to be a very relevant problem in domestic laundry, the processes leading to bad odours have not been studied intensively. In particular, the smell often described as “wet-and-dirty-dustcloth-like malodour” had not been reproduced previously. We developed a lab model based on a bacterial mixture of Micrococcus luteus, Staphylococcus hominis, and Corynebacterium jeikeium, which can produce this odour type and which might allow the detailed investigation of this problem and the development of counteractions. The model uses bacterial strains that have been isolated from malodourous textiles. We could also show that the three volatile compounds dimethyl disulfide, dimethyl trisulfide, and indole contribute considerably to the “wet-fabric-like” malodour. These substances were not only found to be formed in the malodour model but have already been identified in the literature as relevant malodourous substances.

Purification of pulp mill condensates by an adsorptive process on activated carbon

Holzforschung ◽  
2019 ◽  
Vol 73 (6) ◽  
pp. 589-597 ◽  
Author(s):  
José A.F. Gamelas ◽  
Sofia M. Rebola ◽  
Margarita G. Evtyugina ◽  
Valdemar I. Esteves ◽  
Dmitry V. Evtuguin
Keyword(s):  
Activated Carbon ◽  
Volatile Compounds ◽  
Water Cycle ◽  
Black Liquor ◽  
Pulp Mill ◽  
Dimethyl Disulfide ◽  
Pulp Mills ◽  
Wide Range ◽  
New Process ◽  
Pseudo Second Order

Abstract In order to close the water cycle in pulp mills with condensates instead of fresh water, the malodorous/hazardous volatile compounds and colored substances have to be removed by appropriate efficient methods. In the present work, the condensate from the evaporation of black liquor (BL) from a kraft mill was purified by a batch adsorptive process by means of commercial activated carbon (AC). The effluent was found to contain a wide range of aromatic and organosulfur volatile compounds, including toluene, ethylguaicol, syringaldehyde, dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), 2,3-dimethylthiophene, benzothiol and benzothiophene derivatives. Methanol was the major volatile organic component in the condensate (201 mg l−1), which was, however, poorly adsorbed on the AC surface. Aromatics and organosulfur contaminants were adsorbed almost completely in 2–5 min at 23°C under the optimized AC load (900 mg l−1). The treatment allowed the elimination of up to 99% of the obnoxious odor, color and turbidity of the condensate. The adsorption equilibrium followed the Langmuir model and the pseudo-second-order kinetics. The new process could be incorporated in the pulp mill with relatively low additional reagent costs.

Changes in Volatile Compounds during Ripening in Grapes of Airén, Macabeo and Chardonnay White Varieties Grown in La Mancha Region (Spain)

2003 ◽  
Vol 9 (1) ◽  
pp. 33-41 ◽  
Author(s):  
E. García ◽  
J. L. Chacón ◽  
J. Martínez ◽  
P. M. Izquierdo
Keyword(s):  
Volatile Compounds ◽  
Benzyl Alcohol ◽  
Volatile Compound ◽  
The Other ◽  
Optimum Level ◽  
Grape Variety ◽  
La Mancha ◽  
Low Concentrations

Changes in volatile compounds in musts and skins of grapes of Airén, Macabeo and Chardonnay white varieties were determined during ripening. The musts of the Airén variety contained higher concentrations of c-3-hexenol; musts of the Macabeo variety were the richest in t-3-hexenol and 2,4-hexadienal, while the Chardonnay musts stood out for having higher concentrations of benzaldehyde, phenylacetaldehyde and benzyl alcohol. The skins of the three varieties were both qualitatively and quantitatively richer in volatiles than were the musts. The skins of the Airén grapes had the highest levels of nerol. Airén grapes were the only variety in which citronellol was present in the skins. Low concentrations of eugenol were detected in the skins of the Chardonnay grape variety but were not present in the other two varieties. Changes in the concentration of the volatile compounds during ripening were not uniform; this made difficult the determination of the optimum level of ripening for each variety on the basis of the volatile compound content. Nevertheless, results indicated that C6 compounds and terpene concentrations reached a maximum at 6-8 ° Baumé in the Airén grapes and at around 11 ° Baumé in the Chardonnay and Macabeo grapes.

INHIBITION OF BACTERIA BY SOME VOLATILE AND NON-VOLATILE COMPOUNDS ASSOCIATED WITH MILK

1974 ◽  
Vol 37 (11) ◽  
pp. 539-544 ◽  
Author(s):  
D. C. Kulshrestha ◽  
E. H. Marth
Keyword(s):  
Fatty Acids ◽  
Formic Acid ◽  
Salmonella Typhimurium ◽  
Volatile Compounds ◽  
Sulfur Compounds ◽  
Nutrient Broth ◽  
Low Concentrations ◽  
Aerosol Cans ◽  
Chain Fatty Acids

Nutrient broth inoculated with Salmonella typhimurium was dispensed into epoxy-lined aerosol cans. Twenty-five volatile compounds were then individually added to the cans to yield or non-volatile compounds were then individually added to the cans to yield final concentrations of 1, 10, 100, and 1000 ppm of each compound. Compounds tested included fatty acids (formic, acetic, butyric, hexanoic, octanoic and decanoic), aldehydes (formaldehyde, acetaldehyde, propionaldehyde, and glyoxal), ketones (acetone, 2-butanone, and diacetyl), amines (propyl and hexylamine), alcohols (furfurol and methanol), sulfur compounds (methylsulfide, methylsulfone, methanethiol, and ethanethiol), acetonitrile, chloroform, ether, and ethylenedichloride. Bacteria were enumerated at intervals during incubation at 37 C. Shorter chain fatty acids generally inhibited S. typhimurium more than did longer chain acids. At 10 ppm formic acid was most effective of those tested and at 1 ppm fatty acids were generally not inhibitory. Formaldehyde and glyoxal were more inhibitory than acetaldehyde and propionaldehyde. Diacetyl was most effective of the three ketones tested. Low concentrations of acetone or 2-butaoone sometimes enhanced growth of S. typhimurium. Acetonitrile at all concentrations tested significantly inhibited S. typhimurium during the terminal stages of incubation. Ether (10 ppm), chloroform (10 ppm), ethylenedichloride (100 ppm), and methylsulfone (100 ppm) generally caused significant reduction in growth of S. typhimurium. Ethanethiol was more detrimental to growth of S. typhimurium than were methylsulfide or methanethiol; amines were more inhibitory than alcohols.

Removal of odorant dimethyl disulfide under alkaline and neutral conditions in biotrickling filters

2012 ◽  
Vol 66 (8) ◽  
pp. 1641-1646 ◽  
Author(s):  
L. Arellano-García ◽  
A. González-Sánchez ◽  
H. Van Langenhove ◽  
A. Kumar ◽  
S. Revah
Keyword(s):  
Main Product ◽  
Dimethyl Disulfide ◽  
Continuous Treatment ◽  
Batch Experiments ◽  
Reduced Sulfur Compounds ◽  
Biotrickling Filters ◽  
Bacterial Consortia ◽  
Low Concentrations ◽  
Alkaline Conditions ◽  
Neutral Conditions

The aim of this paper was to evaluate the performance of biotrickling filters (BTFs) for treating low concentrations of dimethyl disulfide (DMDS), using different bacterial consortia adapted to consume reduced sulfur compounds under alkaline (pH ≈ 10) or neutral (pH ≈ 7) conditions. Solubility experiments indicated that the partition of DMDS in neutral and alkaline mineral media was similar to the value with distilled water. Respirometric assays showed that oxygen consumption was around ten times faster in the neutrophilic as compared with the alkaliphilic consortium. Batch experiments demonstrated that sulfate was the main product of the DMDS degradation. Two laboratory-scale BTFs were implemented for the continuous treatment of DMDS in both neutral and alkaline conditions. Elimination capacities of up to 17 and 24 gDMDS m−3 h−1 were achieved for the alkaliphilic and neutrophilic reactors with 100% removal efficiency after an initial adaptation and biomass build-up.

scholarly journals Discrimination and risk assessment due to the volatile compounds and the inorganic elements present in the Greek marc distillates Tsipouro and Tsikoudia

OENO One ◽  
2005 ◽  
Vol 39 (1) ◽  
pp. 31 ◽  
Author(s):  
Evangelos H. Soufleros ◽  
Pantelis Natskoulis ◽  
Angeliki S. Mygdalia
Keyword(s):  
Volatile Compounds ◽  
Total Concentration ◽  
Absorption Spectrometry ◽  
Grape Pomace ◽  
Human Consumption ◽  
Inorganic Elements ◽  
Low Concentrations ◽  
Geographic Indications ◽  
High Concentrations

<p style="text-align: justify;">Tsipouro and Tsikoudia are two denominations with geographic indications of the traditional Greek marc distillate, which is produced in continental Greece and in the island of Crete respectively. It is produced by the Greek winegrowers as well as by the professional distillers. To provide data on the safety of domestic Tsipouro and Tsikoudia distillates for human consumption and to draw conclusions from any essential results, which might have an impact on the quality of this product, 23 samples were analysed for: (a) Volatile compounds by the use of gas chromatography, (b) Inorganic elements, using atomic absorption spectrometry and (c) the pH values through-out using standard methods. Data revealed differences between these two denominations, which have been confirmed by the application of a statistic analysis and a PCA. Thus, Tsikoudia was found to contain statistically higher amounts of acetalde-hyde. However, the levels that have been observed did not exceed the official limits. Most of the Tsipouro and Tsikoudia samples also contained low concentrations of estragol, an anise compound, lead and copper, which do not represent a risk to consumer health due to their toxicity. On the other hand, the total concentration of higher alcohols was higher than the official minimum limit (140 g.hl<sup>-1</sup> Absolute Alcohol-AA), while the amylic alcohols rarely exceeded 300 g.hl<sup>-1</sup> AA. The high concentrations of ethyl acetate (&gt;300 g.hl<sup>-1</sup> AA) and ethyl lactate in a few samples showed the necessity of limiting unwanted fermentations in the grape pomace. The analytical study showed that the quality of the marc distillate is, generally, satisfactory. However, it revealed great differences between Tsipouro and Tsikoudia even among the samples of each denomination and, con-sequently, these domestic distillates need standardization and a more systematic production.</p>

Orientation stimulants from substances attractive to Lucilia cuprina (Diptera, Calliphoridae)

1998 ◽  
Vol 38 (5) ◽  
pp. 461 ◽  
Author(s):  
M. C. Morris ◽  
A. D. Woolhouse ◽  
B. Rabel ◽  
M. A. Joyce
Keyword(s):  
Gas Chromatography ◽  
Volatile Compounds ◽  
Mass Spectroscopy ◽  
Dimethyl Sulfide ◽  
Sodium Sulfide ◽  
Gravid Female ◽  
Dimethyl Disulfide ◽  
Lucilia Cuprina

Summary. Liver and liver–sodium sulfide mixtures, sheep faeces, urine and gut mucus are known attractants for the sheep blowfly Lucilia cuprina (Weid.). These substances were analysed for volatile compounds using gas chromatography coupled with mass spectroscopy. The most commonly detected compounds were tested in a bioassay for their potential as attractants for gravid female L. cuprina. Flies orientated towards pulses of dimethyl sulfide at a concentration of 1 µg/g but not 0.1 or 10 µg/g. Ethane thiol elicited a response at a concentration of 10 µg/g but not at 1 µg/g. Dimethyl disulfide did not elicit orientation at 10 µg/g.

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