The anesthetic effects of clove oil and 2-phenoxyethanol on rainbow trout (Oncorhynchus mykiss) at different concentrations and temperatures

In this study, anesthetic effects of five different concentrations of 2-phenoxyethanol (0.2, 0.3, 0.4, 0.5 and 0.6 ml/L) and clove oil (0.50, 0.75, 1.00, 1.25 and 1.50 ml/L) on rainbow trout (Oncorhynchus mykiss) were studied at temperatures 7, 13 and 18ºC. For this purpose, 900 fish (39.08 ± 1.13 g and 15.48 ± 0.21 cm) were used in the experiment. Induction time of 2-phenoxyethanol and clove oil varied between 1.05 and 3.36 min at all concentrations, except for 0.2 ml/L (for 2-phenoxyethanol only) and at every temperature application. Full recovery time occurred between 2.44 and 7.14 min for 2-phenoxyethanol and 3.23 - 6.11 min for clove oil. It was found that full recovery times significantly increased with increase in 2-phenoxyethanol concentrations (r^2=0.81). The same increasing trend was observed in clove oil, but the increase was not strong compared to 2-phenoxyethanol (r^2=0.21). On the other hand, full induction times of 2-phenoxyethanol and clove oil significantly declined with the increase in concentrations (r^2=0.74; r^2=0.84 for 2-phenoxyethanol and clove oil, respectively). Based on the ideal induction (less than 3 min) and recovery (less than 5 min) time criteria, it can be suggested that the most appropriate concentrations for rainbow trout were 0.3, 0.4 and 0.5 ml/L for 2-phenoxyethanol and 0.50, 0.75 and 1.00 ml/L for clove oil

Opinion of the Scientific Committee on Consumer Safety (SCCS) – Final version of the opinion on Phenoxyethanol in cosmetic products

International audienceThe SCCS considers 2-phenoxyethanol safe for use as a preservative with a maximum concentration of 1.0%, taking into account the information provided. The toxicokinetics default factor of 4.0 can be reduced to 1.0 yielding a minimum Margin of Safety (MoS) of 25 instead of 100 for the safety assessment of 2-phenoxyethanol. Therefore, the MoS of about 50 for children also covers this specific age group who might be higher exposed to 2-phenoxyethanol than adults. This Opinion does not take into account exposure from sources other than cosmetics

Neutral genetic drift can aid functional protein evolution

BACKGROUND: Many of the mutations accumulated by naturally evolving proteins are neutral in the sense that they do not significantly alter a protein's ability to perform its primary biological function. However, new protein functions evolve when selection begins to favor other, "promiscuous" functions that are incidental to a protein's biological role. If mutations that are neutral with respect to a protein's primary biological function cause substantial changes in promiscuous functions, these mutations could enable future functional evolution. RESULTS: Here we investigate this possibility experimentally by examining how cytochrome P450 enzymes that have evolved neutrally with respect to activity on a single substrate have changed in their abilities to catalyze reactions on five other substrates. We find that the enzymes have sometimes changed as much as four-fold in the promiscuous activities. The changes in promiscuous activities tend to increase with the number of mutations, and can be largely rationalized in terms of the chemical structures of the substrates. The activities on chemically similar substrates tend to change in a coordinated fashion, potentially providing a route for systematically predicting the change in one function based on the measurement of several others. CONCLUSIONS: Our work suggests that initially neutral genetic drift can lead to substantial changes in protein functions that are not currently under selection, in effect poising the proteins to more readily undergo functional evolution should selection "ask new questions" in the future

The use of tricaine methanesulfonate, clove oil, metomidate, and 2-phenoxyethanol for anesthesia induction in alewives (Alosa pseudoharengus)

Anesthetics are widely used in routine aquaculture operations to immobilize animals for tagging, spawning, handling, and vaccination. A number of anesthetics are currently available for finfish, but their efficacy and optimal dosage is highly species-specific. The efficacy of the anesthetic agents (tricaine methanesulfonate (MS-222), clove oil, metomidate, and 2-phenoxyethanol (2-PE)) was studied in adult, juvenile (133.3 ± 1.5 mm, 27.5 ± 8.9 g), and larval Alewives (Alosa pseudoharengus Wilson). In an initial trial, wild-caught adults were anesthetized with doses of 87.5-112.5 mg/L MS-222, 25-40 mg/L clove oil 0.5-5.0 mg/L metomidate and 0.125-0.550 mg/L 2-PE. Optimal doses for anesthesia were similar for larvae and juveniles, and were identified as: 75-100 mg/L MS-222, 40 mg/L clove oil, 5-7 mg/L metomidate, and 500 mg/L 2-PE. All juvenile fish survived 48 hours post-exposure to each optimal dose. In a longer-term (24 hour) sedation experiment, juvenile alewives were netted and exposed to low clove oil (2.5 and 5.0 mg/L) and metomidate (0.25 and 0.50 mg/L) doses, and plasma cortisol was measured. Fish exposed to the clove oil treatments exhibited a cortisol stress response that was prolonged in the higher dose treatment. No cortisol stress response was observed in the metomidate treatments. Overall, optimal acute anesthesia doses for alewives were similar to those reported for other species, and metomidate may be useful for longer-term sedation

Does the anaesthetic influence behavioural transmission of the monogenean Gyrodactylus gasterostei Glaser, 1974 off the host?

The aim of this study was to investigate the use of the anaesthetic 2-phenoxyethanol on the transmission factors of gyrodactylid and to ascertain how this may affect in the colonisation of new hosts using the Gyrodactylus gasterostei Glaser, 1974 - Gasterosteus aculeatus L. model which is a simple and successful system to examine aspects of transmission of parasites from live and dead fish. Laboratory experiments include determining the maturity (presence of male copulate organ) and reproductive (presence of daughter) status of transmitting worms, in order to consider the factors that influence parasite option to migrate to a new individual of the same host species. This study demonstrates that parasites with a Male Copulate Organ (MCO) present are more likely to abandon the host and attempt a host transfer. The use of the anaesthetic 2-phenoxyethanol does not affect transmission of gyrodactylids which leave the host to colonise a new host. Finally, the use of other anaesthetic although its relative importance with respect to transmission remains uncertain.Department of the Environment, Food and Rural Affairs (Defra); Overseas Research Students Awards Scheme (ORSAS) UK; Consejo Nacional Ciencia y Tecnologia, Mexico CONACyT [171032]info:eu-repo/semantics/publishedVersio

Termite Trail-Following Behavior Elicited by Ballpoint Pen Ink

Termite trail-following behavior occurs because of pheromones produced in the sternal gland of the termites and secreted when the sternal gland touches a substance. 2-phenoxyethanol, a chemical found in ballpoint pen ink, is structurally similar to the trail-following pheromones and causes the termites to respond with trail-following behavior. This study investigated the difference in trail-following behavior between ballpoint pen ink, which contains 2-phenoxyethanol, and Sharpie ink, which does not contain 2-phenoxyethanol. The termites were placed on a square drawn with either ballpoint pen ink or Sharpie pen ink. Time spent on each of the squares was measured. We predicted that termites would spend more time with the ballpoint pen ink and less time with the Sharpie ink, due to the presence of 2-phenoxyethanol. Our class results show that there is a significant difference between time spent on the ballpoint pen ink condition and time spent on the Sharpie ink condition, which supports our prediction and is supported by the results of previous studies. While our class results are significant, our group results are not significantly different between the ballpoint pen ink condition and the Sharpie ink condition, due to a lower sample size which is easily skewed by outliers

Structure-Guided Recombination Creates an Artificial Family of Cytochromes P450

Creating artificial protein families affords new opportunities to explore the determinants of structure and biological function free from many of the constraints of natural selection. We have created an artificial family comprising ~3,000 P450 heme proteins that correctly fold and incorporate a heme cofactor by recombining three cytochromes P450 at seven crossover locations chosen to minimize structural disruption. Members of this protein family differ from any known sequence at an average of 72 and by as many as 109 amino acids. Most (>73%) of the properly folded chimeric P450 heme proteins are catalytically active peroxygenases; some are more thermostable than the parent proteins. A multiple sequence alignment of 955 chimeras, including both folded and not, is a valuable resource for sequence-structure-function studies. Logistic regression analysis of the multiple sequence alignment identifies key structural contributions to cytochrome P450 heme incorporation and peroxygenase activity and suggests possible structural differences between parents CYP102A1 and CYP102A2

2-Phenoxyethanol derivatization in ink dating determination

Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio

Comparison of the Antiseptic Efficacy of Tissue-Tolerable Plasma and an Octenidine Hydrochloride-Based Wound Antiseptic on Human Skin

Colonization and infection of wounds represent a major reason for the impairment of tissue repair. Recently, it has been reported that tissue-tolerable plasma (TTP) is highly efficient in the reduction of the bacterial load of the skin. In the present study, the antiseptic efficacy of TTP was compared to that of octenidine hydrochloride with 2-phenoxyethanol. Both antiseptic methods proved to be highly efficient. Cutaneous treatment of the skin with octenidine hydrochloride and 2-phenoxyethanol leads to a 99% elimination of the bacteria, and 74% elimination is achieved by TTP treatment. Technical challenges with an early prototype TTP device could be held responsible for the slightly reduced antiseptic properties of TTP, compared to a standard antiseptic solution, since the manual treatment of the skin surface with a small beam of the TTP device might have led to an incomplete coverage of the treated area

The percutaneous permeation of a combination of 0.1% octenidine dihydrochloride and 2% 2-phenoxyethanol (octenisept®) through skin of different species in vitro

<p>Abstract</p> <p>Background</p> <p>A water based combination of 0.1% octenidine dihydrochloride and 2% 2 - phenoxyethanol is registered in many European countries as an antiseptic solution (octenisept^®) for topical treatment with high antimicrobial activity for human use, but octenidine based products have not been registered for veterinary use yet. The aim of the present study was to investigate whether octenidine dihydrochloride or 2 -phenoxyethanol, the two main components of this disinfectant, permeate through animal skin <it>in vitro</it>. Therefore, permeation studies were conducted using Franz-type diffusion cells. 2 ml of the test compound were applied onto 1.77 cm²split skin of cats, dogs, cows and horses. To simulate wounded skin, cattle skin was treated with adhesive tapes 100 times, as well. Up to an incubation time of 28 hours samples of the acceptor chamber were taken and were analysed by UV-HPLC. Using the method of the external standard, the apparent permeability coefficient, the flux J_max, and the recovery were calculated. Furthermore, the residues of both components in the skin samples were determined after completion of the diffusion experiment.</p> <p>Results</p> <p>After 28 hours no octenidine dihydrochloride was found in the receptor chamber of intact skin samples, while 2.7% of the topical applied octenidine dihydrochloride permeated through barrier disrupted cattle skin. 2 - phenoxyethanol permeated through all skin samples with the highest permeability in equine, followed by bovine, canine to feline skin. Furthermore, both components were found in the <it>stratum corneum </it>and the dermis of all split skin samples with different amounts in the examined species.</p> <p>Conclusion</p> <p>For 2-phenoxyethanol the systemic impact of the high absorption rate and a potential toxicological risk have to be investigated in further studies. Due to its low absorption rates through the skin, octenidine dihydrochloride is suitable for superficial skin treatment in the examined species.</p