Mechanism of Action of Fatty Alcohol Ethoxylate on Foliar Penetration of Dimethomorph into Cucumber

Fatty Alcohol Ethoxylate에 의해 유도되는 Dimethomorph의 오이 엽면 침투 기작

  • Yu, Ju-Hyun (Chemical Biotechnology Research Center, Korea Research Institute of Chemical Technology)
  • 유주현 (한국화학연구원 바이오정밀화학연구센터)
  • Published : 2008.06.30


The foliar uptake of dimethomorph into cucumber was assessed by spray application of aqueous dimethomorph solution containing fatty alcohol ethoxylate (FAE) or fatty acid alkyl ester as activator adjuvants. Afterward, the possible mechanism of action of FAE on foliar penetration of active ingredient was suggested by speculating on the effect of lipophile and hydrophile of FAEs. The amount of absorbed dimethomorph induced by polyoxyethylene mono-9-octadecenyl ether (6 moles ethylene oxide, $C_{18=9}E_6$) was linearly related to the concentrations of surfactant as well as dimethomorph in spray solution, suggesting that it is simply a diffusion phenomenon of the solute molecule through a cuticular membrane from leaf surface. Octadecanol attached to FAE was most effective lipophile on the leaf penetration of dimethomorph. And, the more ethylene oxide had the polyoxyethylene chain of FAE up to 20 moles, the higher the uptake rate was. Therefore, the role of lipophile of FAE on dimethomorph penetration to cucumber leaf, probably, is to modify the physico-chemical properties of cuticular membrane to be permeable to dimethomorph, and the polyoxyethylene chain having less than 20 moles ethylene oxide, which is moderately permeable to cuticular membrane by its molar volume, is to let the physically-modified cuticular membrane to be maintained for a longtime.

침투성 증진 물질로 fatty alcohol ethoxylate(FAE) 혹은 지방산 에스테르를 함유하는 dimethomorph 수용액을 오이 잎에 분무 살포하여 침투율을 측정하고, FAE의 각기 다른 분자내 친수기와 친유기의 구성에 따른 dimethomorph의 침투율을 조사함으로써 FAE에 의해 유도되는 dimethomorph의 침투 기작을 추론하였다. Polyoxyethylene mono-9-octadecenyl ether(ethylene oxide 부가몰수 6 몰, $C_{18=9}E_6$)에 의해 유도된 dimethomorph의 오이 엽면 침투량은 분무액 중의 $C_{18=9}E_6$의 농도와 dimethomorph농도에 비례하였다. 따라서 FAE의 엽면 침투와 그로 인하여 유도되는 dimethomorph의 침투성은 잎 표면으로부터 내부를 향하여 일어나는 단순한 확산 현상임을 알 수 있었다. 동일한 몰농도로 첨가된 지방산 에스테르와 FAE를 이용한 실험에서 dimethomorph의 오이 잎 침투성 증진에는 친유기로 octadecanol이 가장 효과적이었으며, 여기에 부가된 친수기 polyoxyethylene은 ethylene oxide(EO) 부가몰수가 20 몰까지 증가할수록 더욱 효과적이었다. 따라서 FAE 계면활성제의 친유기는 dimethomorph의 확산 침투가 용이해지도록 주로 오이 잎의 cuticular wax의 이화학적 성질을 변화시키는 역할을 하며, 20 몰 이하의 EO가 부가된 친수기 Polyoxyethylene은 FAE의 몰부피를 증가시킴으로써 FAE 자체의 확산 침투 속도를 늦추고 cuticular membrane 내에 오래 머물게 함으로써 dimethomorph의 침투가 용이하도록 친유기에 의해 변화된 cuticular wax의 이화학성을 오래 동안 유지하는 역할을 하는 것으로 추정되었다.


  1. Baker, E. A. (1980) Effect of cuticular components on foliar penetration. Pestic. Sci. 11:367-370
  2. Bauer, H. and J. Sch?nherr (1992) Determination of mobilities of organic compounds in plant cuticles and correlation with molar volumes. Pestic. Sci. 35:1-11
  3. Baur, P., J., Sch?nherr and B. T. Grayson (1999) Polydisperse ethoxylated fatty alcohol surfactants as accelerators of cuticular penetration. 2. Separation of effects on driving force and mobility and reversibility of surfactant action, Pestic. Sci., 55, 831-842
  4. Cho, K. Y., J. H. Yu, H. K. Lim, G. J. Choi and J. H. Kim (1999) Composition and Method for Measuring the Foliar Uptake of Agrochemicals. Patent KR-0314600
  5. Dehne, H-W (1997) Enhancement of the efficacy of fungicides, European patent application 0806141A1
  6. Grayson, B. T., J. D. Webb, D. M. Batten and D. Edwards (1996a) Effect of adjuvants on the therapeutic activity of dimethomorph in controlling vine downy mildew. I. Survey of adjuvant types. Pestic. Sci. 46:199-206<199::AID-PS334>3.0.CO;2-N
  7. Grayson, B. T., S. L. Boyd and D. Walter (1996b) Effect of adjuvants on the therapeutic activity of dimethomorph in controlling vine downy mildew. II. Adjuvant mixtures, outdoor-hardened vines and one-pack formulations. Pestic. Sci. 46:207-213<207::AID-PS335>3.0.CO;2-B
  8. Grayson, B. T., D. M. Batten and D. Walter (1996c) Adjuvant effects on the therapeutic control of potato late blight by dimethomorph wettable powder formulations. Pestic. Sci. 46:355-359<355::AID-PS364>3.0.CO;2-U
  9. Holloway, P. J. and D. Stock (1990) In Industrial Applications of Surfactants II (ed. D. R. Karsa), Special Publication No. 77, Royal Society of Chemistry, Cambridge, pp. 303-337
  10. Kerler, F. and J. Schonherr (1988) Permeation of lipophilic chemicals across plant cuticles: Prediction from octanol/water partition coefficients and molecular volumes. Arch. Environ. Contam. Toxicol. 17:7-12
  11. Schonherr, J. (1993) Effects of alcohols, glycols and monodisperse ethoxylated alcohols on mobility of 2,4-D in isolated plant cuticles, Pestic. Sci., 39:213-223
  12. Schonherr, J. and P. Baur (1994) Modelling penetration of plant cuticles by crop protection agents and effects of adjuvants on their rates of penetration. Pestic. Sci. 42:185-208
  13. Schreiber, L., M. Riederer, and K. Schorn (1996) Mobilities of organic compounds in reconstituted cuticular wax of barley leaves: Effects of monodisperse alcohol ethoxylates on diffusion of pentachlorophenol and tetracosanoic acid. Pestic. Sci. 48:117-124<117::AID-PS448>3.0.CO;2-3
  14. Stevens, P. J. G. and M. J. Bukovac (1987) Studies on octylphenoxy surfactants. Part 2: Effects on foliar uptake and translocation. Pestic. Sci. 20:37-52
  15. Stevens, P. J. G., E. A. Baker and N. H. Anderson (1988) Factors affecting the foliar absorption and redistribution of pesticides. 2. Physicochemical properties of the active ingredient and the role of surfactant, Pestic. Sci. 24:31-53
  16. Stock, D., B. M. Edgerton, R. E. Gaskin and P. J. Holloway (1992) Surfactant-inhanced foliar uptake of some organic compounds: Interractions with two model polyoxyethylene alipatic alcohols. Pestic. Sci. 34:233-242
  17. Stock, D. and P. J. Holloway (1993) Possible mechanisms for surfactant-induced foliar uptake of agrochemicals. Pestic. Sci. 38:165-177
  18. Tomlin, C. D. S. (2000) In 'The Pesticide Manual' Twelfth Ed., British Crop Protection Council, Surrey, UK
  19. Yu, J. H., G. J. Choi, H. K. Lim, J. H. Kim and K. Y. Cho (2001) Influence of surfactants on foliar uptake of dimethomorph into cucumber plant and fungicidal activity against cucumber downy mildew. J. Korean Soc. Agric. Chem. Biotechnol. 44:109-115
  20. Yu, J. H., K. Y. Cho and J. H. Kim (2000) Review of the study on the surfactant-induced foliar uptake of pesticide. The Korean journal of Pesticide Science 6:16-24