Circe Biotechnologie GmbH

Circe Biotechnologie GmbH is an Austrian industrial biotechnology company based in Vienna that develops gas-fermentation processes to convert waste gases — notably methane (CH₄) and captured CO₂ — into single-cell protein and biodegradable polymers. The company describes itself as "the fermentation people," reimagining one of the earliest biological processes to create modern, scalable solutions for agriculture, aquaculture and bioplastics. Its stated mission is to deliver climate-resilient and climate-friendly products at industrial volume rather than laboratory concepts. The company's core technology platform is a patented "combined process" and "innovative mixing" approach that enables versatile manufacturing of multiple protein and plastic derivatives from waste gases. Circe reports a portfolio of patent filings, including WO2024124267, WO2024228166, WO2025097199 and A50144/2026. Its first commercial product line, Circe FEED, is a naturally fermented bacterial protein containing roughly 70% protein with an essential amino acid blend, positioned as a sustainable alternative to fishmeal in aquaculture and farmed-animal nutrition, as well as in pet food. A second line, Circe Biodegradable POLYMERS, targets sustainable packaging and plastics. The company traces its origins to 2018, when its founder team began process development and filed its first bioreactor patent. In early 2020 it signed a collaboration agreement with an institute that launched its bacterial library, and in 2021 it finalised two academic joint ventures with partners at Technische Universität Wien. Circe now runs two sites: R&D gas-fermentation laboratories in Seestadt, Austria (with 2×19 L and 1×150 L stirred-tank reactors and a 400 L loop fermenter) and a scale-up site in Teesside, United Kingdom, featuring a 5,000 L loop fermenter. The Teesside Base Camp Site (BCS) is intended to pave the way to a first Circe Mega Site (CMS), a planned 20,000-tonne-per-year protein production facility, for which the company says it is in early discussions with trapped and biogas supply chains. Circe is privately held and does not appear to be listed on a stock exchange. It is engaged in international R&D projects, including INSPIRE, and collaborates with academic partners in Austria, including Universität Wien. Its positioning sits at the intersection of the circular bioeconomy — the name CIRCE stands for "circular" — industrial-scale fermentation, alternative proteins and sustainable materials.

Circe Biotechnologie GmbH emerged from a founder team that began process development in 2018 and filed its first bioreactor patent that year. The company's name is derived from "circular," reflecting its focus on the circular bioeconomy. In early 2020, Circe signed a collaboration agreement with an institute, which kicked off its bacterial library — a collection of microbial strains central to its fermentation work. In 2021, two academic joint ventures were finalised with partners at Technische Universität Wien, deepening its applied-science base. Today, its in-house and collaboration partners for applied science are located in Austria, at Universität Wien. The company has progressively refined both its bioprocess and its strains, creating what it describes as an optimised bioprocess for high-yield productivity. Its technology platform is built around a patented "combined process" and "innovative mixing" approach that uses waste gases — including captured CO₂ — to manufacture multiple protein and plastic derivatives. Circe reports patent filings including WO2024124267, WO2024228166, WO2025097199 and A50144/2026. Circe operates two sites. Its R&D gas-fermentation laboratories are in Seestadt, Austria, equipped with 2×19 L and 1×150 L stirred-tank reactors and a 400 L loop fermenter. Its scale-up site, the Base Camp Site (BCS), is in Teesside, United Kingdom, and features a 5,000 L loop fermenter with associated downstream processing. The BCS is intended to pave the way to the company's first Circe Mega Site (CMS), a planned 20,000-tonne-per-year protein production facility. Circe says it is in very early discussions with both trapped and biogas supply chains for this first full Mega Site. The company is engaged in three international R&D projects, among them INSPIRE. Its first product line, Circe FEED, is a naturally fermented bacterial protein with roughly 70% protein and an essential amino acid blend, positioned as a sustainable alternative to fishmeal in aquaculture and farmed-animal nutrition, as well as in pet food. A second line, Circe Biodegradable POLYMERS, targets sustainable packaging. Circe frames its technology as enabling bulk product manufacturing without primary agricultural products, which it says gives scalability and climate resilience.

• 2021

  Finalises two academic joint ventures with partners at Technische Universität Wien.

• 2020

  Signs collaboration agreement with an institute, kicking off its bacterial library.

• 2018

  Founder team begins process development and files first bioreactor patent.

• Operates R&D gas fermentation labs in Seestadt, Austria, and a scale-up site (BCS) in Teesside, UK.

• Engaged in three international R&D projects, including INSPIRE.

Industrial-scale gas fermentation for climate-resilient protein and bioplastics from waste gases and captured CO₂.

• Circe FEED

  Naturally fermented bacterial single-cell protein with roughly 70% protein and an essential amino acid blend; a sustainable alternative to fishmeal for aquaculture, farmed animal nutrition and pet food.

• Circe Biodegradable POLYMERS

  Biodegradable polymer products derived from the company's gas fermentation platform, aimed at sustainable packaging.

• CIRCE Technology platform

  Patented combined process and innovative mixing platform enabling versatile manufacturing of multiple protein and plastic derivatives from waste gases and captured CO₂.

1. 1Circe.atcirce.at
2. 2Circe.at Aboutcirce.at
3. 3Wikidata: Circe Biotechnologie GmbHwikidata.org