Unibio says the funds will be used to roll out new global production capacity, grow operating capabilities, and accelerate innovation and commercialisation.
Saudi Industrial Investment Group is one of the first privately owned petrochemical companies in Saudi Arabia.
The process is independent of weather deviations that otherwise impact the production of protein using traditional methods.
Known as Uniprotein, the product is approved for feed in the European Union and global registrations are in progress.
The protein provides nutrition on par with, or better than other high-quality proteins, such as fishmeal, Unibio claims. It has been tested successfully in various aqua and animal species and is free from pesticides, fully traceable, and non-GMO.
The production of Unibio's protein for direct human consumption is under development.
The investment in Unibio will be paid in two tranches, with the first comprising approximately US$25 million (€23 million) scheduled for immediate payment. The second is subject to applicable Foreign Direct Investment approvals.
BofA Securities acted as placement agent to Unibio for the transaction.
"We are delighted to welcome SIIG as a significant investor in Unibio," said David Henstrom, CEO of Unibio.
"Their investment will enable us to play a pivotal role in meeting our customers' need for sustainable protein. Unibio's technology will improve food security and speed up the process of feeding the world in a sustainable way," Henstrom added.