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iFERMENTER - CONVERSION OF FORESTRY SUGAR RESIDUAL STREAMS TO ANTIMICROBIAL PROTEINS BY INTELLIGENT FERMENTATION

Periodic Reporting for period 2 - iFermenter (iFERMENTER - CONVERSION OF FORESTRY SUGAR RESIDUALSTREAMS TO ANTIMICROBIAL PROTEINS BY INTELLIGENTFERMENTATION)

Reporting period: 2019-11-01 to 2021-04-30

Our project addresses the under utilization of sugar residual streams from the pulp industry. Plant dry matter, the so called lignocellulosic biomass, is the largest renewable biomass feedstock on Earth. Biorefineries processing such feedstock are projected to make a substantial contribution to a future sustainable economy. By 2030 we have the potential to develop a competitive bio-based European economy producing 30% of our chemicals and 25% of transport fuels, safeguarding millions of jobs. There are numerous lignocellulosic biorefineries in operation today, e.g. sulfite pulp mills in Finland, Norway, Sweden, Austria, Czech, Switzerland, USA and Canada, and several sugar beet biorefineries in UK and Finland. In the last years 5 full scale plants have been put in operation; 1 in Italy, 2 in US and 2 in Brazil. Unfortunately, lignocellulosic biorefineries struggle with low profitability. Such biorefineries have sugar streams that are not converted to higher value chemicals. Some produce low value ethanol (€0.3-0.6 /kg), but most incinerate their sugar to energy use by lack of other alternatives. These companies could therefore be more competitive by adding production of high value products from the sugar platform.
Being able to convert these large amounts of residual sugars (over 14 MT/y in EU alone) will obviously have great economical, and environmental benefits for the society. Instead of using sugars that originate from food, such as corn starch, sugar beet and sugar canes for the fermentation of chemicals, it is desirable to use sugars originating from industrial processes such as the pulp industry, that anyway produce cellulose. It will increase job opportunities, will strengthen the economy, and may help to change the demography of agriculture, from sugars to microbial fermentation to growing food for people.
The overall objective is to be able to utilize these sugar streams that contain inhibitors and complex sugar mixtures that are currently unsuitable for microbial fermentation of high value chemicals. In addition, we intend to exploit these sugars to produce high value (>100 USD/kg) compounds that have great benefits in medicine, and are valuable as food and feed additives.
First, we analyzed and studied our complex sugar mixtures originating from the pulp industry, including its content, variability and the presence of inhibitors. We have then designed microbial strains that can tolerate the inhibitors of these sugar residual streams. Moreover, we were also active on modifying the microbial strains and engineer them to produce antimicrobials with high value. Our natural bacteria (the wild type) could not consume 80% of the sugars in the residuals mixtures. Now we have strains that can consume almost 100% of the sugars in the mixture (tested by real industrial sugar streams). We also worked to modify our strains to produce valuable antimicrobials that are not naturally produced by this host. As for now, we have strains that can produce one type of antimicrobial. Because the products our cell factories will produce are antimicrobials, compounds that naturally kill microbial cells via membrane damage, we studied the effect of high concentrations of these compounds on the fermentation culture, and modified the cells to be able to tolerate high concentrations, such that the concentrations we will late produce will be high. We have now strains that can tolerate the inhibitors and higher concentrations of the antimicrobials than regular (wild type strains). We also worked on the design of fermentation process that is suitable for these microbial strains: via an advanced digital control system, we intend to control the fermentation process in an optimal manner. Until this report, we have designed the model for the controller, an estimator, algorithm based on mathematics and statistics that can correct different measurements during the fermentation process and integrate them in a manner that enables us to achieve optimal control.
To summarize, our main results include
1) strains that consume residual sugar streams (novelty)
2) strains that can tolerate large amount of the residual streams in fermentation
3) strains that produce one type of antimicrobial (novelty)
4) New digital fermentation technology.
Our strains that we designed can consume and tolerate industrial sugar mixture and produce antimicrobials. This achievement is beyond the state of the art: Currently this industrial mixture is only exploited by strains of yeasts in the production of the low value bioethanol. Our cell factories are efficient in the consumption and conversion of these sugars to high value compounds.
The potential impact is obvious:
Environmentally, it will promote the full exploitation of sugars that are currently incinerated or used to produce low value compounds. We will show by LCA studies that our process with our strains reduces at least 20% of the carbon emission compared to the state of the art process to produce the same compounds in the industry. Moreover: today’s processes use glucose-like sugars that originate in food, such as corn starch and sugar canes, while our process will exploit industrial sugars byproducts that cannot be consumed by humans or animals.
Economically, the project will contribute to circular economy, because of the exploitation of the residual streams (Figure below). It will add value chain to the pulp industry, that will have the opportunity to exploit the process and produce high value compounds, adding to their existing processes (production of the low value ethanol). If they choose not to produce themselves, they will be able to sell their sugars (that are not currently sold) to companies that are interested in our advance and effective fermentation process that relies on these sugars. The project (our strains + our technology) will interconnect companies that are traditionally not have mutual commercial interest, and may create at least two novel value chains: Pulp industry to medicine, pulp industry to food and feed industries.
For the European society and jobs creation: Because we also develop digital technologies in addition to biotechnology (we actually integrate the two fields), we will create a process that we will exploit by later upscaling and developing a demo plant (after application for funding). This will enable the European fine chemical industry to compete with the low-cost production of antimicrobials and other high value compounds (e.g. vitamins, food additives and cosmetics) in China and other countries in the far-east. It will enable them to produce larger quantities of better quality products that will be manufactured in Europe. With other words, we expect our high efficient technology that enables the production of high quality compounds to outcompete the low-cost labor that is possible in the far-east, therefore creating high skilled jobs in the EU and export of high quality products.
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