# From Plant Material to Environmentally Friendly Plant Growth Stimulators: Betaine-Based Ionic Liquids

## TL;DR

This paper introduces eco-friendly plant growth stimulators made from betaine-based ionic liquids that are effective and safe for the environment.

## Contribution

The novel synthesis of betaine-based ionic liquids using natural byproducts and their evaluation as environmentally friendly plant growth stimulators.

## Key findings

- The ionic liquids stimulate plant growth by 40–60% compared to traditional potassium salts.
- The compounds are practically nontoxic to freshwater and saltwater organisms.
- They have minimal toxic effects on soil microorganisms except for those with the longest alkyl chains.

## Abstract

Following global trends, the main issue is to ensure
that humanity
can progress without harming the environment. This article outlines
the synthesis of novel ionic liquids composed of an alkylbetaine cation,
whose structure is based on glycine-betaine (a byproduct of sugar
beet production) and an anion based on indole-3-butyric acid (a natural
auxin found in plants). The article details the synthesis method used
and demonstrates its negligible environmental impact. In addition,
the main physicochemical properties of ionic liquids and their initial
substrates have been assessed. Biological studies indicate that these
ionic liquids effectively stimulate plant growth compared to the potassium
salt of indole-3-butyric acid by approximately 40–60%, promoting
positive effects on plant growth after sowing, while they may also
contribute to seed protection before sowing. Furthermore, environmental
studies have shown that these compounds are unlikely to pose a threat
to freshwater and saltwater organisms, as they fall into the Practically
Nontoxic to Slightly Toxic class in the case of A. franciscana and the Practically Nontoxic to Moderately Toxic class in the case
of D. magna. Moreover, ionic liquids exhibited
a benign effect on soil microorganisms, with toxic effects occurring
only for salts containing the longest alkyl chains (MIC = 62.5–250
μg·cm–3).