Plants surfactant effects

There seems to be little more evidence in the literature to allow a more coherent discussion of the effects of surfactants on herbicide activity and explanation of their intrinsic phytotoxicity. It may be that with such a diversity of plant structures the task of rationalizing the activity of surfactants (with the complex pattern of wetting effects, evaporation retardation, solubilization, particle size alteration of precipitated active ingredient, membrane permeability effects and intrinsic biological effects on enzyme systems) will be more daunting than with the relatively simple problem that must be faced with surfactant effects on the human organism. It is likely, however, that study of surfactant effects on plant cells will give useful information to help in the elimination of effects on mammalian cells. 

Surfactant effects on adsorption of herbicides on to soil have been investigated and suggested to be a factor to be considered in the overall effect of surfactant on toxicity towards the plant. The degradation, mobility and uptake of one such compound, picloram [4-amino-3,5,6-trichloropicolinic acid] (pK = 3.4) is affected by adsorption-desorption processes in solids. Picloram adsorption on to soils at pH 5 was reduced by 1 % anionic surfactant [284]. The mechanism involved in picloram adsorption included protonation of the molecule, metal-ion bridging and interaction with metal ions. Picloram adsorption was enhanced by cationic surfactants, suggesting that hydrophobic adsorption of the cationic monomers on to the soil provides a cationic surface for interaction of the anionic picloram. Different soils with different pH values resulted in some variations in these effects which are presented in Table 10.29. 

Further examinations have been done in the biodegradation ecotoxicity sequence rest (BEST). In this test a realistic diluted effluent of the modified OECD confirmatory test (DIN 38412, part 26) is tested continually on daphnia reproduction over three generations. It can be said that the effluents of an OECD confirmatory plant (feed 10 mg/L LAS), containing nondegraded surfactants and catabolites, have no negative effect on the juvenile and adult daphnia even in the third generation and do not influence their reproduction [296]. 

In five pilot plants that can be used to simulate the route of anionic surfactants from the consumer via the effluent purification plant to the receiving water, possible toxic effects of residual surfactant content and breakdown products of the secondary alkanesulfonates were investigated [102]. As indicators of the effects on living organisms of the effluent in the receiving water, flora and fauna that are frequently encountered in the p-mesosaprobic zone were used as models. The embryo-larval test was also employed as an additional method for the detection of toxic compounds in the water. 

Schonherr J, Baur P (1996) Effects of temperature, surfactants and other adjuvants on rates of uptake of organic compounds. In Kerstiens G (ed) Plant cuticles an integrated functional approach. BIOS Scientific Publishers, Oxford UK, chap 6... 

A series of publications dedicated to soil-associated LAS has been authored or initiated by the surfactant-manufacturing industry. It was already in 1990 when Mieure et al. [12] presented a safety assessment for LAS for terrestrial plants and animals comparing measured LAS concentrations in soil environments with the lowest effect concentrations for typical organisms.1 In 1998, de Wolf and Feijtel [13]... 

In the development of the protein-fatty acid condensates it was possible to combine the renewable resources fatty acids (from vegetable oil) and protein, which can be obtained from both animal waste (leather) as well as from many plants, to construct a surfactant structure with a hydrophobic (fatty acid) and a hydrophilic (protein) part (Fig. 4.12). This was carried out by reacting protein hydrolysate with fatty acid chloride under Schotten-Baumann conditions using water as solvent. Products are obtained that have an excellent skin compatibility and, additionally, a good cleaning effect (particularly on the skin) and, in combination with other surfactants, lead to an increase in performance. For instance, even small additions of the acylated protein hydrolysate improve the skin compatibility. An... 

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