Tallow amphopolycarboxyglycinate-stabilized silver nanoparticles: new frontiers in development of plant protection products with a broad spectrum of action against phytopathogens

Abstract

Sustainable agriculture calls for minimal use of agrochemicals in order to protect the environment. It has caused an increase in the rate of nanoparticles use, in particular silver nanoparticles (AgNPs) due to their safety for mammals, unique biological activity and a broad spectrum of action against fungal and bacterial pathogens. Until now the use of AgNPs dispersions in the agricultural sector has been essentially limited due to many factors decreased their stability (mixing with other pesticides, presence of electrolytes). We present a versatile synthesis of polyampholyte surfactant (tallow amphopolycarboxyglycinate) stabilized AgNPs. We took a close look at unique aggregation behavior (via dynamic light scattering and UV-vis spectroscopy) and biocidal activity of obtained silver colloids. AgNPs are characterized by exclusively high aggregative stability in the presence of coagulating agents NaNO 3 and NaSO 4 (up to 1 M), during drying/redispergation, and frost/defrost cycles. The dispersion of AgNPs shows high biocidal activity (EC 50 is ten times lower than commercial species ones) with respect to Phytophthora infestans and phytopathogenic fungi. This points to the possibility of successful application of silver preparations within agriculture with the goal of partial reduction of the use of toxic and expensive synthetic antibiotics and pesticides.

Silver Nanoparticles and Polyphenol Inclusion Compounds Composites for Phytophthora cinnamomi Mycelial Growth Inhibition

“…An EC 50 value of amphopolycarboxyglycinate-stabilized AgNPs against P. infestans of 3.1 µg·mL −1 was reported by Krutyakov et al [ 41 ], i.e., a 30 and 6 times higher concentration than those obtained for the AgNPs combined with gallic acid, silymarin and ferulic acid inclusion compounds in DES, respectively.…”

Fungicidal and antibacterial activity of the hydrogel compositions with silver

“…It is shown below that for exponential model used in our work, both indicators are identical, and, therefore, the obtained results can be compared with the previous publications using the IR index [13][14][15][16][17][18][19].…”

“…Both indicators, D/D0 and D 2 /D0 2 , are relevant for the calculation of the median or half-maximal (50%) effective concentration (EC50) of the PPAs on the basis of the experimental relationship between these indicators of relative growth and PPA concentration. Most of laboratory tests of PPA do not consider the growth of pathogens, but rather focus on the efficiency of its suppression (Inhibition Rate, IR) depending on PPA doses [13][14][15][16][17][18][19]. For example, in Kim et al [13] the indicator IR is calculated as:…”

“…The latter is an experimental product of the Ural Chemicals Factory from patent-pending technology [4][5][6][7][8][9][10][11][12][13][14][15][16][17]. The colloidal silver is an experimental product "Zeroxxe" of AgroChimProm GC (http://tdahp.ru/en/,) that contains silver nanoparticles with a size of 10-70 nm superficially modified with environmentally safe biodegradable amphiphilic surfactant (tallow amphopolycarboxyglycinate-stabilizer [18]. To prepare the growth medium for the microorganisms, hydrogels and potato agar were mixed in a 1:1 ratio with a dose of 10 g of each substance per 1 L of medium.…”

Biodegradation of Materials in Soils and Soil Constructions: Experiments, Modeling and Prevention

“…Silver, as an inhibitor of biological activity, and as a component of protective gel compositions in the form of nanoparticles (experienced "Zeroxxe" of AgroChimProm GC (http://tdahp.ru/en/) with amphiphilic surfactant-stabilizers [24] and in the form of ionic (chemically pure AgNO3) solution were added to SSPH in the concentration (for the active substance -Ag) 10, 100, 1000 ppm per mass of water in swollen hydrogel. Variants of the experiments with silver inhibitors included pure gel compositions, and their mixtures with water extracts of rotting potato tubers and calcined to 500 ºC sandy substrate.…”