Making Agriculture More Sustainable: An Environmentally Friendly Approach to the Synthesis of Lignin@Cu Pesticides

Abstract

Despite its high chemical value, most of lignin is nowadays burnt as low value fuel. It is therefore important to find innovative applications for its use. Copper compounds are used as plant protection products for more than 50 different diseases in viticulture, arable crops, hops, and horticulture, and they have been used for more than 100 years. Minimization of copper in agriculture has become a fundamental issue due to its negative environmental impact. Here we present a series of hybrid organic−inorganic materials (lignin@Cu), deriving from the combination of lignin with brochantite, Cu 4 (OH) 6 SO 4 . Optimization of the synthetic procedures has allowed us to isolate lignin-based materials containing different percentages of copper, where the brochantite crystals are featured by different morphologies and dimensions. A more environmentally safe synthesis of lignin@Cu materials by mechanochemistry is also investigated, which reduces the amount of water used and makes easier and faster the isolation of the final materials. Tests on strawberry and tomato plants in a greenhouse have highlighted a significative efficacy of the lignin@Cu materials against different pathogens at a copper content much lower than the one of copperbased commercial pesticides. A crystal morphology−activity correlation is also traced out. The synergic activity of lignin and copper ions can be used to reduce the copper content for efficient pathogen control. Moreover, the mechanochemical approach ensures a greener synthetic approach, in a perspective of a more sustainable agriculture.

Changing the Game of Time Resolved X-Ray Diffraction on the Mechanochemistry Playground by Downsizing

“…[11][12][13][14] It is increasingly clear that many traditional solution based chemical reactions can be performed in the presence of very little or no solvent using mechanochemical approaches. 15 Providing "greener" and potentially less expensive strategies than traditional solution methods, 1,[16][17][18] mechanochemistry was dubbed by the International Union for Pure and Applied Chemistry (IUPAC) as one of the 10 chemical innovations that will change our world. 19 Despite decades of research, the fundamental principles which drive mechanochemical reactions remain poorly understood.…”

Control of Grapevine Downy Mildew by an Italian Copper Chabasite-Rich Zeolitite

“…Specific studies are focused on the reduction in the use of cupric fungicides to limit the environmental impact of copper in the soil, following the EC regulations 1981/2018 [24,[26][27][28][29]. In particular, some studies assessed alternatives to copper or new formulations with lower copper content [30].…”

Mechanochemical Transformations of Biomass into Functional Materials

“…Recently, Pelagatti and co‐workers also demonstrated successful metal incorporation into lignin for application in plant protection and antimicrobial materials (Figure 22). [479] Interestingly, it was seen that only by including a LAG procedure with 2 mL of water within the planetary ball milling procedure did the Cu‐containing brochantite crystalline phase appear, after just 1 h. In contrast, with up to 4 h of milling, no LAG procedure resulted in the Cu crystalline phase of posnjakite to be dominant, with no brochantite formation evident.…”