Production of auxin by Aspergillus flavipes through solid-state cultivation: scale-up and application in the rooting of Eucalyptus

Abstract

The use of plant growth-promoting microorganisms is among the technological tools that can make agricultural systems more productive and cause less impact on human health and the environment. The proposed product is composed of the fungus Aspergillus flavipes, cultivated through solid-state fermentation (SSF). A. flavipes has the potential to promote growth and stimulate rooting due to the ability to produce metabolites such as the phytohormone indole-3-acetic acid (auxin). Preliminary results show the effect of the microorganism on the rooting of eucalyptus seedlings. The production process has already been tested in the laboratory, the results were patented and published as a scientific article (TRL 4). However, for turning the academic research into a commercial product it is necessary to scale up the production, test the shelf-life and evaluate the product effect on the rooting of seedlings in a relevant environment (TRL 5), in addition, it is necessary to adapt the design and to initiate the product registration, according to the regulatory agencies. In this project, the scale-up will be evaluated in two types of bioreactors, plastic bags, and packaged beds. The scale-up will be adapted regarding the aeration and temperature maintenance in experiments that will evaluate the production increase up to 450 times the initial volume. The product stability will be analyzed in a shelf-life study that will include different storage conditions for up to 6 months. The product applicability will be evaluated in a greenhouse experiment to assess the impact on the production of Eucalyptus seedlings. At the end of the project, a cost analysis will be carried out to quantify the cost per µg of indole-3-acetic acid and analogs and market analysis will be carried out to identify direct and indirect competitors. The data will allow to evaluate the technical feasibility of the technology and to prove the potential of the product as a biostimulant. Therefore, in phase 2 of PIPE-FAPESP, we hope to install the bio-factory, adapt the product design, carry out further tests in greenhouses, with different cultivars and start registering the product. (AU)