Biofungicide based on essential oils developed to combat soybean disease

By Rodrigo de Oliveira Andrade  |  FAPESP Innovative R&D – Researchers at Linax, a company based in Votuporanga, São Paulo state, Brazil, have developed a fungicide made of essential oils, with low environmental impact and high economic potential, for use against soybean disease.

The solution was developed via a project supported by the FAPESP Innovative Research in Small Business Program (PIPE). It consists of a blend of oils extracted from different plants and encapsulated by natural polymers which release the substance slowly and gradually, extending its period of action and reducing the risk of fungal resistance development.

Prototypes of the technology were tested against Phakopsora pachyrhizi, the fungus that causes Asian soybean rust, one of the worst diseases affecting this crop in Brazil. It attacks the leaves, undermining their ability to perform photosynthesis and form healthy grains. If it is not properly controlled, it can ruin up to 90% of a plantation and cause massive financial losses.

The solution developed by Linax is as effective as the fungicides most used to combat the disease in Brazil. “Application of a half-dose of our solution in conjunction with a half-dose of conventional fungicide is more effective than application of conventional fungicide alone,” says Nilson Borlina Maia, an agricultural engineer and a partner in Linax. “So adding a dose of our solution based on essential oils reduces the volume of conventional fungicides in use, which is positive because they’re harmful to human and animal health and to the environment.”

The technology is the result of a partnership between Linax and Santa Clara Group, an agricultural input supplier in Ribeirão Preto, São Paulo state. The group recently announced it was acquiring Linax, which would become part of Santa Clara Agrociência, its biopesticide division.

Linax’s fungicide will be launched this year. According to Maia, the same strategy will be used against fungi that cause disease in other crops, and environmentally sustainable solutions are under development to boost the effectiveness of biological pesticides. “We’re conducting a project with UNESP [São Paulo State University] to encapsulate fungi and bacteria that can be used against crop pests and diseases, thus protecting them against ultraviolet radiation and enhancing their viability and effectiveness,” he said.

Innovation track record

Linax has a track record of innovations involving essential oils and natural polymers, many of which were developed with the support of PIPE and the Business Research Support Program (PAPPE) run by FAPESP in partnership with the Brazilian Innovation Agency (FINEP), an arm of the Ministry of Science, Technology and Innovation (MCTI).

Linax itself was born from a project supported by PIPE, starting in 2004, to extract linalool oil from basil (Ocimum basilicum). Linalool is widely used by the perfume industry and is a key ingredient of Chanel No. 5. It has long been extracted from Aniba rosaeodora, a severely endangered tree native to the Amazon, leading to its near-extinction. According to a 2002 estimate, 2 million of these trees had been felled for linalool harvesting up until then. The species is now found only in a few parts of Amazonas state, including the municipalities of Parintins, Maués, Presidente Figueiredo and Novo Aripuanã.

The research that gave rise to the project and the firm began years earlier, in 1998, when Maia set out to screen 18 plants for linalool, including coriander, bay laurel (Laurus nobilis), cinnamon and orange, as well as basil. “I was looking for an alternative to the destruction of A. rosaeodora,” he said.

He soon ruled out bay laurel. “The tree contains a lot of linalool but takes a long time to reach adulthood, making its cultivation for commercial extraction unviable. Coriander and cinnamon don’t contain linalool. Orange trees contain very little,” he recalled.

Although he failed to find a plant with as much linalool as A. rosaeodora, where it can reach 90% of the plant’s essential oil, Maia found basil to be an economically viable source of natural oil that can substitute for linalool in many cosmetics, perfumes and other hygiene and beauty products.

The project was supported at the time by the Campinas Institute of Agronomy (IAC, an arm of the São Paulo State Department of Agriculture and Supply). Large numbers of basil seedlings were produced and commercial plantations were quickly established. To facilitate extraction of essential oil in the laboratory. Maia developed a stainless steel mini-distiller that does not release toxic residues and produces high-quality output. “In conventional glass distillers, which are hard to handle, loading and unloading the plant material takes about an hour on average. With the mini-distiller we created, it takes about a minute and the distilling is controlled by an automated electrical system,” he said.

Linax presented the mini-distiller at the 3rd Brazilian Symposium on Essential Oils in Campinas in November 2005, which opened up new business opportunities for the firm. “We began to produce and market essential oil distillers for scientific laboratories, perfumeries and small, medium and large farmers. We’ve sold more than 200 units since then,” Maia said.

In 2020, Linax was awarded funding by FAPESP and FINEP via the PIPE-PAPPE Grant Program to develop an automated control system for its distillers based on artificial intelligence software. “The system controls and monitors the entire essential oil distilling process, while also enhancing its efficiency,” he said.

Linax has now fully mastered all stages of linalool production. It helps clients produce seedlings and grow the varieties they need. It can also assist harvesting and distilling of essential oil with 95% purity, assuring environmental, economic and social sustainability. “Linax also helps clients produce other essential oils, which can be used to develop new products that don’t yet exist on the market,” Maia said.

The strategy offers family farmers in the Votuporanga area an opportunity for extra income and helps strengthen the production of essential oils as a new agribusiness segment.