Bioresources in Circular Bioeconomy Series: Value Chains’ Transparency and Sustainability Maja Berden Zrimec, Anteja ECG Ljubljana . Stuttgart . Boston . Tbilisi 1 Bioresources in Circular Bioeconomy Author: Maja Berden Zrimec Reviewer: Fernando Quesada Series: Value Chains’ Transparency and Sustainability Series Editor: Dr. Maja Berden Zrimec Design: Preblisk, Jamšek s.p. Electronic edition, English language Published in 2022 by Anteja ECG, Ljubljana, Slovenia Kataložni zapis o publikaciji (CIP) pripravili v Narodni in univerzitetni knjižnici v Ljubljani COBISS.SI-ID 117116931 ISBN 978-961-07-1218-3 (PDF) Ljubljana, julij 2022 2 Bioresources in Circular Bioeconomy Series: Value Chains’ Transparency and Sustainability Maja Berden Zrimec, Anteja ECG INTRODUCTION 4 ALGAE 6 BIOMASS PRODUCTION 7 ALGAE FOR FOOD AND ANIMAL FEED 8 PHYTO-PHARMACEUTICALS AND COSMETICS 9 AGRICULTURAL UTILISATION 10 BIOFUELS AND ENERGY 11 WASTEWATER TREATMENT AND BIOMASS VALORISATION 12 AGRICULTURAL WASTE 13 AGRO-WASTE RESOURCES 14 VALORISATION 15 A VARIETY OF OPTIONS 16 FOREST RESIDUES 17 FOREST/WOOD RESIDUES 18 VALORISATION OF THE RESIDUES 19 WHAT IS THE HOLD-BACK? 20 IN CONCLUSION 21 SOURCES 22 READ MORE ABOUT CIRCULAR BIOECONOMY AND BIORESOURCES IN ANTEJA’S BLOGS 23 INTERESTING LINKS 23 3 INTRODUCTION The “take-make-waste” approach of using and processing our resources is paving the way to destroying our health and the environment. Resource extraction has more than tripled since the 1970s. In 2019, global use of materials has surpassed 100 billion tonnes, of which over 90% is being wasted (Circle Economy 2022). The extraction and processing of materials, fuels and food contribute half of the total global greenhouse gas emissions and over 90% of biodiversity loss and water stress (IRP 2019, UNEP 2022). If we continue business as usual, we will eventually reach planetary boundaries (IRP 2019). It is predicted that global material use could almost double by 2060 (IRP 2019, Circle Economy 2022). Although some measures to prevent this scenario are well on the way, the solution is not simply to upgrade the renewable energy and material use efficiency, but to combine these efforts with the circular approaches. In contrast to the linear economy, which uses natural resources for products that end up as waste, the circular economy strives to create a closed-loop system with reuse, sharing, repair, remanufacturing, recovering, and recycling. In circular systems, waste materials and energy become resources, either for processes in industry or as natural resources (i.e., organic fertilisers, source of high-value compounds). In either case, waste, pollution, and carbon emis-Figure 1. A sustainable and circu- sions are significantly reduced. lar bioeconomy according to EC . 4 Circular bioeconomy combines the approaches of bioeconomy and circular economy. The circular economy tries to reduce the demand for new natural resource extraction by recycling the already obtained ones, thus reducing the waste to a minimum. The circulating resources can still be fossil based, but their use is much more efficient and prolonged due to the advantageous technologies and circular supply chains. Bioeconomy, on the other hand, essentially relies on utilising biological resources to produce energy, materials, and chemicals. This means using renewable biological resources from land and sea, like crops, forests, fish, animals and micro-organisms to produce food, materials and energy (EC). In this respect, both approaches depend on the innovation and development of new products and technologies. In circular bioeconomy, two concepts can complement each other. There-fore, the resources coming into the circular economy become, by defi-nition, bio-based and are not of fossil origin — so-called bioresources. The combination of bioeconomy and circular economy is interesting also because it has a high potential to lead to more sustainable production and consumption, but only if several other criteria are met. For example, although bioeconomy is based on bioresources, it still largely relies on non-renewable energy and biomass production with the help of fossil-based raw materials like nitrogen fertilisers, organic chemicals, and polymers (Tan & Lamers 2021). To become sustainable, circular bioeconomy must thus go beyond simply switching fossil resources with renewable bioresources. It requires low-carbon energy inputs, sustainable supply chains, and innovative dis-ruptive conversion technologies for the sustainable transformation of renewable bioresources into high-value bio-based products, materials, Figure 2. Algae present an extremely interesting opportunity for the circular bioeconomy as they can produce biomass from the waste substrates - Spirulina sp. under the microscope (Al- gen, algae technology centre). 5 and fuels (Tan & Lamers 2021). In this context, the European Commission views the circular bioeconomy as a framework to reduce the dependence on natural resources and transform manufacturing to enable sustainable production and processing of renewable resources from land, fisheries, and aquaculture into bio-based products and bioenergy. Another important aspect is the establishment of viable supply and value chains to enable the flow of materials and energy from bioresources to bio-based products and energy. At Anteja, we prepared a series of stud-ies to present the variety of bio-based resources, their valorisation and circularity. ALGAE Figure 3. Water2Return, Euro - pean H2020 project on turning wastewater facilities into bio-re- In the scope of circular bioeconomy and bio-based resources, algae seem to fit fineries by REcovery and REcy-perfectly into the picture. On one hand, their biomass is full of macro- and micro-cling of nutrients from waste- nutrients as well as interesting pharmaceutical compounds. On the other hand, water and converting them into they can be easily cultivated in a wide variety of wastewater and waste streams, added-value products for a circu-treating, and cleaning the water as they grow. In addition, they get rid of a nasty lar economy in agriculture, also wastewater odour and sequester carbon dioxide to produce oxygen. agriculture, with the help of algae. also with the help of algae. Algae have a huge potential as a bioresource for food, animal feed, chemicals, and materials. While macroalgae are currently mostly produced in the sea, microalgae are the ones cultivated on land. But don’t be alarmed. One of the great things about algae cultivation is that they don’t compete for agricultural land like some other crops used for biofuel production. They can be cultivated in desert or degraded areas, unsuitable for any other use. Moreover, they don’t need so much land in the first place. Comparing their production with agricultural crops, microalgae can produce 4–15 tonnes of protein per hectare per year, while soybeans usually reach 0.6–1.2 tonnes (van Krimpen et al. 2013). 6 Biomass production Large-scale algae biomass production mostly takes place in (photo) bioreactors or raceway ponds. Bioreactors can be installed indoors for the rapid biomass production of specific ingredients, for example, pigments. They can also be used outdoors and installed vertically to enhance the yield per land area. Because they are a closed system, algae can be cultivated in fairly sterile conditions. Raceway ponds are open systems and thus more prone to environmental impacts. Nevertheless, they provide quality biomass and at the same time require much lower initial investment and maintenance costs. They can be completely open or placed in a greenhouse, the latter for the purpose of continuous production in sub-optimal climatic areas (i.e., winter season in continental Europe). Spirulina (Arthrospira platensis) for food is produced in this way. Raceway ponds also allow relatively simple production of biomass in the waste streams, from municipal wastewater to anaerobic digestate from the biogas plants. Figure 4. NWE Interreg ALG-AD project tackles the possibilities to create value from waste nu- trients by integrating algal and anaerobic digestion technology. Photobioreactors can be seen on the lower left side. 7 Figure 5. Spirulina production in the greenhouse (Source: Algen, algal technology centre, llc). Several other cultivation systems are researched and developed in the hope of achieving even higher production. Thin-layer systems, biofilms and algal turf scrubbers are some of the many innovative and promising production systems developed around the world. Algae for food and animal feed Figure 6. Dried spirulina for hu- Algae are rich in proteins, lipids, amino acids, vita- man consumption (Algen, algal mins, pigments, and other beneficial compounds. technology centre, llc). They typically contain essential amino acids, essen- tial fatty acids, including omega-3, omega-6 and omega-7, as well as vitamins A, B, C, E and K (see FDC data for Spirulina). Proteins can amount up to 60% in some species, comparable to soybeans. People living in the coastal areas have been aware of their benefits for thousands of years and includ- ed seaweed in their diets for nutrition. Seaweeds are still an important food source in many coun- tries, typically in Asia. In light of rising awareness about the benefits of algae, seaweed production is also currently increasing on other continents, in- cluding Europe. Microalgae consumption is not yet so common, but the case for using them as a food source is compel- ling. Currently, microalgae from two genera are pre- vailing in the food sector: Chlorella and Arthrospira (Spirulina). Microalgae are rarely consumed fresh (mostly for logistic and conservation reasons). They are mainly available in dry form as tablets, powder, or flakes. Algae are already a part of the fish diet in aquaculture, and they are extensively 8 studied as a feed additive for pets and farm animals that could lower the need for the use of antibiotics. Many other microalgae are being studied as a food source. Current efforts are mainly being put into developing productive and cost-effective mass cultivation and harvesting techniques. Phyto-pharmaceuticals and cosmetics The number of algal species has been estimated somewhere from 30.000 to potentially 1 million (Guiry 2012). They are extremely heterogenous and thus represent a huge genetic pool of various compounds, some of which have already been known for a very long time (e.g., agar and carrageenan). They can be used for production of agricultural biostimulants due to their hormone content. Biopesticides derived from algae are gaining in importance as well in the scope of European Green Deal goals and Farm to fork strategy. Figure 7. The European Green Deal goals. Algae extracts contain active substances like carotenoids, chlorophyll, fu-coxanthine, fucosterol, squalene, mycosporine-like amino acids, and more. All are known as strong antioxidant agents. They can have pigments like lutein, a known carotenoid beneficial for the eyes (also known as “the eye vitamin”) which also protects the skin from damage caused by UV radia-tion. Another perspective antioxidant is ulvan, a polysaccharide extracted from sea lettuce. Various algae contain a lot more bioactive compounds which are important for skin care, sun protection, and other care products. 9 Agricultural utilisation Algae and their extracts have a long tradition of being used in agriculture as soil conditioners and enhancers of crop productivity. The benefits of algae application in the agricultural field are numerous. These include stimulation of seed germination, enhancement of growth (shoot and root elongation), improved water and nutrient uptake, frost and saline resistance, biocontrol and resistance to pathogenic organisms, fertilisation, and remediation of contaminated soil. Adding algae to the soil also improves its water holding capacity and its structural characteristics. It also compensates for the deficiency of nitrogen, phosphorus, potassium, and other minerals. The beneficial effects of algae in agriculture (especially in promoting higher crop yields) are being reported in numerous research publications. Figure 8. Growing tomatoes with the help of algae (Algen and Uni- versity of Ljubljana, Slovenia, in the scope of Water2Return project). 10 Figure 9. European Green Deal and Farm to Fork 2030 targets for sustainable food production. Algae can importantly contribute to the 2030 targets for sustainable food production as their application in agricultural production significantly reduces the need for the use of chemical pesticides, mineral fertilisers and antimicrobials. They are also a perfect candidate for purposes of support-ing organic farming if used together with advanced agricultural approaches like crop cycling and conservation farming. Biofuels and energy Figure 10. Production of biofuels with algae grown in municipal wastewater in Aqualia (Spain) in the scope of All-Gas project (Photo courtesy of Frank Rogal- la, Aqualia) Algae can be used for production of biogas, bioethanol, and biodiesel. Their biomass can be used for production of electrical power in biogas plants. The components of cell wall and storage sugars can be used to produce bioethanol and the lipids can be used to produce biodiesel. The reason for limited utilisation of algae for biofuel is simple: the cost is still too high and can’t compete with fossil fuels in the current market. One way to lower the costs is algae cultivation in wastewater, which is by far cheaper than cultivation in pure chemical media. Another trend-line is co-production of biofuel with higher value products such as phyto-pharmaceuticals or animal feed. In biorefineries, components of algal biomass can be utilised for many different purposes, from lipids for biofuels and proteins for animal feed to extracts of interesting bioactive compounds like pigments, vitamins or agar. 11 Wastewater treatment and biomass valorisation Algae systems present attractive opportunities for multiple industries because they can grow in most types of wastewaters as long as they are not toxic. They recycle nutrients that would otherwise end up as pollutants in the natural environment. Algae take up carbon, nitrogen, phosphorus, and many other minerals and metals, and turn them into valuable biomass. Biomass can then be used as a secondary raw material to produce many new products: from low-added-value biomaterials, biofuels and bi-ofertilisers to high value-added substances like pigments, proteins, lipids, biopesticides, agricultural biostimulants or bioactive compounds for cosmetics and pharmaceuticals. Figure 11. Algae raceway pond as a part of the wastewater treat- ment facility in Seville, Spain (Algen, Water2Return project ). The systems can be seamlessly added to the existing technology as side-streams, thus not requiring restructuring of a current installation; be it in the wastewater treatment system of the sewage plant or in the industrial technology systems. The addition of an algal raceway pond could complement or even replace the secondary and tertiary treatment of wastewater, substantially reducing the production of unwanted sludge (not allowed for agricultural use in many countries). Algae can also be utilised to stabi-lise the liquid phase of anaerobic digestate in biogas plants, significantly cutting down the storage and transport logistic costs and greenhouse gas emissions. 12 Figure 12. Algae (Photo: Algen archive). In conclusion, algae have a lot to offer and it is encouraging to see the technological advancements and research of different species that will make all the possibilities discussed here spring to life. AGRICULTURAL WASTE Many types of agricultural residues have traditionally been considered to be waste material. However, in circular bioeconomy, they have a new role as the bioresource for value-added products and energy generation. This is certainly a very welcome step forward given that we produce an enor-mous amount of agricultural waste. The latest Eurostat data show that Figure 13. Generation of vegetal waste in 2018 (Eurostat 2022). 13 the EU produced 2,337 million tonnes of total waste in 2018. From this, 58.45 million tonnes were vegetal waste stemming from the agriculture and food industry. Worldwide, almost a third of the food produced is never eaten. This is roughly 1.3 billion tons of food waste per year (Bas-Bellver et al. 2020). In the case of fruits and vegetables, 45% of the biomass goes to waste. By FAO estimation, the residues have an even higher share of 60% (Bas-Bellver et al. 2020). Consequently, the global annual generation of biomass waste is in the order of 140 Gt (Tripathi et al. 2019). In the EU, about 23 Mt of dry biomass per year is available as the residual straw from cereals. The major global crops (wheat, maize, rice, soybean, barley, rapeseed, sugarcane and sugar beet) produce almost 3.3 Gt of residue (fresh weight per year) in the countries and regions with large biomass potential (Europe, USA, Canada, Brazil, Argentina, China and India) (Tripathi et al. 2019). Agro-waste resources Agricultural waste comes from the cultivation and processing of agricultural products such as fruits, and vegetables as well as animal products that are not covered in this blog (Gurdil et al. 2021). The waste can be in the form of liquids, slurries, or solids. Its composition mostly depends on the nature and kind of farm activities, seasonal changes, climate, and soil quality. Figure 14. Straw is a good feed- stock for producing energy. Only a small amount of biomass waste is currently utilised as a feedstock for industrial applications and electricity generation. The reason is not that companies simply don’t want to bother with the recycling of waste. As many industries entering the circular economy, agriculture also generally lacks innovative new technologies that enable waste valorisation. Nevertheless, the utilisation of waste is more than worthwhile. To become truly sustainable, it is imperative that bioresources for industry do not compete with food crops for agricultural land. In this respect, agricul-14 tural waste is an excellent bioresource that can replace the use of crops (and farmland) for biofuel production. Waste valorisation also supports the EU’s primary objective that Member States should use biomass for energy purposes without harming the environment, endangering efforts to mitigate climate change, or causing negative social impacts (Ymeri et al. 2020). Cereal crops are the major contributor to the huge quantities of annual global generation of agricultural residue. Globally, 66% of the residual plant biomass comes from the cereal straw (stem, leaf, and sheath material). This amount is followed by sugarcane stems and leaves, and other residual biomass including the ‘oil crops’, roots and tubers, nuts, fruits and vegetables (Tripathi et al. 2019). Valorisation Agricultural waste represents an abundant source for biofuel production. Still, most residues are normally discarded or burned, although, as discussed earlier, many have the potential for energy production (Tripathi et al. 2019). Residues generated from crops, such as sugarcane, rice, ground nuts and coffee beans have already been used as a fuel source. None-theless, they are significantly under-utilised (Tripathi et al. 2019). A lot of agricultural and food waste also ends up in the biogas plants where they are used to produce biogas for households and industry. Generating biogas from the agricultural residues enables an important decrease in Figure 15. Fruit and vegetable residues are generally packed with nutrients and bioactive compounds. non-renewable energy consumption and particularly greenhouse gas re-lease from storing manure and agricultural waste. 15 Cellulose, hemicellulose, and lignin-rich residues can be used to produce chemicals, resins and enzymes. They can also be converted into biofuel by biochemical or thermochemical processes. The technique depends on the residue characteristics. Feedstocks with more than 30% moisture content, C/N ratio of less than 30%, and high cellulose and hemicellulose content are better suited for biochemical conversion with microorgan-isms and enzymes, eventually being converted into biogas, bioethanol, or biodiesel (Gurdil et al. 2019). Materials with less than 30% moisture, C/N ratio higher than 30%, and a high lignin content are converted thermochemically and subsequently treated to produce synthesis gas or syngas, bio-oil, biochar, and bio-coal (Gurdil et al. 2019). Although thermochemical processing can be used on a broad spectrum of wastes, it is a less sustainable biochemical conversion method because it involves fossil fuel consumption and greenhouse gas emissions (Gurdil et al. 2019). Fruit and vegetable processing produces wastes, such as seeds, peels, or pulp, which are generated in the different steps of the processing chains. These residues are generally packed with high concentrations of bioactive compounds, often even higher than that of the edible part of the fruit. Consumers increasingly prefer products with natural ingredients, that can be produced from agro-waste. The use of natural bioactive compounds is especially welcome in commonly consumed processed foods where they can improve their nutritional value (for example, see our blog: Healthy food with nutritious moringa). Fruit and vegetable powders are another way of consuming food residue products. Powdered ingredients from vegetable waste have the potential to be used as colouring, savouring, or preservative agents. They can also serve to increase the nutritional value of processed food by contributing to the development of nutritious and safe diets with a reduced environmental impact. Technologically, some development is needed to produce safe and homogenous products from typically heterogenous waste. Processes like cleaning, drying, and milling are relevant in achieving the quality powder with the desired functional properties. A variety of options In our blogs we have already written about the reusable residues from several crops. For example, mango peels contain carotenoids such as pro-vitamin A compound, alpha- and beta-carotene, lutein. They also contain polyphenols like quercetin, kaempferol, gallic acid, caffeic acid, catechins, magniferin, and tannins. Many bioactive compounds in the peel, kernel and pulp are known for their antimicrobial, anti-diabetic, anti-inflammatory, and anti-carcinogenic properties. Waste water from shea butter production has pesticidal properties and the press cake and husks from processing have potential as fertilisers and fuel stock. 16 The cashew shell has a high amount of oil content and the shell deriva-tives can be used for lubricants, waterproofing, and paints. Cashew nut-shell liquid (CNSL) is an important industrial product obtained while processing the raw nuts. The cashew apple waste is used as a form of energy bagasse. Its fermented cultures can be used in probiotics or for condition-ing of the soil in agriculture. Many phytochemicals can be found also in the pineapple peel. The leaves of some pineapple cultivars can be used for textiles. Bromelain is extracted mostly from stems and is a desirable substance in cosmetics, medicine, and as a meat tenderiser. The production of avocado fruits results in large quantities of peel and seeds which contain a number of phytochemicals with health benefits, including the reduction of inflammatory diseases. The residues of avocado contain essential oils with considerable amounts of polyphenolic compounds such as proanthocyanins, catechins and quercetin glycosides. Seeds are a good source of carbohydrates like hemicelluloses, fibres, and starch (30%). The high fibre content of the residues after lipid extraction allows their use in the preparation of flour, which is suitable for bakery products and pasta. FOREST RESIDUES Energy derived from biomass (bioenergy) is one of the most important renewable energy sources today. It is expected to play a major role in replacing fossil fuels in the global energy systems and in reducing greenhouse gas (GHG) emissions over the next decades (Thiffault & Beaulieu 2021). Wood is increasingly perceived as a green, renewable source of energy (FAO 2022b) and the wood processing industry is highly developed. Nevertheless, there is a large volume of forestry/wood residues remaining un-utilised. It is generally assumed that for every cubic meter of wood extracted from the forest, there is another cubic meter of forest residue Figure 16. Wood fuel production or post-harvest waste (Koopmans & Koppejan 1997, Kuhn 2021, Tripathi et by country (FAOSTAT 2022). al. 2019). 17 Wood is already a basic energy resource for billions of people. One-third of households worldwide and two-thirds of those in Africa use wood as their main fuel for cooking, heating, and boiling water (FAO 2022b). So-called wood fuel (firewood, charcoal, pellets, wood gas, bio-oil, etc.) production is continuously rising and has reached almost 2 billion m3 in 2020 (FAOSTAT 2022). Figure 17. Common types of wood fuel (FAO 2022). Forest/wood residues From the global production of wood-derived biomass, 60% goes to energy generation, 20% to industrial ‘round wood’ and the remaining 20% is primary production loss that remains in-field to decay (Tripathi et al. 2019). The residues emerge at three stages. Primary (forest) residues and waste is the residue that remains on site upon completion of harvesting for the roundwood (Kuhn 2021); some of which is collected for fuelwood. Secondary residue is produced while processing the wood into products. Tertiary residues are formed after the end-use of wood products (Thif-Figure 18. World production of fault & Beaulieu 2021). Initial processing waste (about 34%) includes wood residues in 2020 was eval-branch trimmings, bark removal, slabs, blocks, sawdust and further trim-uated by FAO to be almost 233 mings. About 12% of this material arrives at the mill (Tripathi et al. 2019). million m3 (FAOSTAT 2022). 18 After kiln drying, shavings (about 6%) and sawdust/trimming (about 2%) add to the total amount of waste (FAO 2022a). Through the value chain, approximately 80% of forest tree mass is estimated to be lost as waste, with about 20% of the wood ending up in the form of kiln-dried sawn product (Tripathi et al. 2019). V alorisation of the residues Forest residuals have traditionally been used for energy production and are still considered the largest and most important wood-based biomass source for biofuel production in the future (Gregg et al. 2020). In addition, various low-volume, high-value bioproducts are becoming increasingly important to the industry. The market share of bioplastics has great potential, and other end products are gaining interest as well. These include bio-lubricants, bio-solvents, biosurfactants, enzymes, and biopharma-ceuticals (Gregg et al. 2020). In the biorefinery approach, two trajectories are emerging: (1) gasification of biomass and biofuel production (diesel, ethanol), and (2) separation of products with high added value such as polymers (Gregg et al. 2020). The decision on the most promising biomass conversion processes depends on many factors. These include the type and quantity of available biomass, the desired end-uses, the relevant governmental policies, environmental standards, and economic conditions, as well as project-specific factors (d’Espiney et al. 2021). Within the thermochemical conversion process options (combustion, pyrolysis, gasification, and liquefaction), the combustion of residues in small-scale decentralized facilities can be considered the most promising present option for forest residues exploita-tion (d’Espiney et al. 2021). Other options currently involve technological challenges and uncertain investment costs. Integrated solutions, such as anaerobic co-digestion of complementary substrates, can be appeal-ing because of their energy potential (d’Espiney et al. 2021). Innovations are expected particularly in new extraction methods of hemicellulose or lignin, and in the development of new enzymes (Gregg et al. 2020). Figure 19. After the harvesting for roundwood, large amount of residues remain on site as waste. 19 What is the hold-back? The forestry industry has been slow to invest in technology and in the new market for valorising residuals. This may be due to weak market pull, high capital needs, and risk-adverse strategies among the few incumbent firms (Gregg et al. 2020). That is why the value chain for forest residues is still mainly hierarchical and rather undeveloped (Gregg et al. 2020). An un-predictable and inconsistent policy landscape is the major barrier for the deployment of biorefinery technology (Gregg et al. 2020). Another challenge is the lack of resources for investing in innovation of new products. Most of the development is focused on the improvement of traditional effective and efficient harvesting, sawing of logs and decreased waste production (Gregg et al. 2020, d’Espiney et al. 2021). Establishing forest biorefineries also requires a different set of skills. One option is industrial symbiosis or eco-industrial parks where firms can reduce costs by cascad-ing energy and utilising the by-products of other actors as well as avoid-ing transport costs (Gregg et al. 2020). Luckily, more recently many new firms are competing for the biomass to valorise it into variety of products. Thus, value chains are shifting towards more circular and sustainable ways, making the industry greener by cooperation across sectors. 20 IN CONCLUSION Bioresources have great potential to replace a good part of raw materials in variety of industries. Most of the important sources come from agriculture, forestry, fisheries, and aquaculture, as well as industrial and agricultural waste streams. These resources are abundant but severely under-utilized Most notably, this may be because of the lack of commer-cialised technologies and appropriate policies. Some regulatory agencies are already taking steps in the right direction. The EU Waste Framework Directive requires the increase of recycling to minimise waste and reduce reliance on landfill. In the US, Department of Energy (DOE) and Department of Agriculture (USDA) have mandated that 5% of heat and power energy, 20% of liquid transportation fuel and 25% of chemicals and materials should come from biomass by 2022 (Tripathi et al. 2019). We must be very careful to use the biological resources and environment in a sustainable and efficient way. Many technologies for recycling still require fossil fuels and produce greenhouse gas emissions. It is also imperative that the bioresource-based production does not compete for the land used for food production. The connection between circular economy and bioeconomy might be a step in right direction if we consider sustainability at all stages. This includes processing and waste reuse with minimum energy and fossil fuel utilisation. Additionally, new value chains must be established to enable the appropriate environment for the companies to transfer to circularity. Together with technological development, circular value chains will be able to utilise most of the primary and secondary resources, and finally reduce the pressure on the virgin material reserves. 21 SOURCES Bas-Bellver C., Barrera C., Betoret N., Segui L. (2020): Turning Agri-Food Cooperative Vegetable Residues into Functional Powdered Ingredients for the Food Industry. Sustainability 12: 1284; doi:10.3390/su12041284 Circle Economy (2022): Circularity Gap Report 2022. d’Espiney A., Marques I.P., Pinheiro H.M. 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Sustainability 12: 4009; doi:10.3390/su12104009 22 Read more about Circular bioeconomy and Bioresources in Anteja’s blogs Agricultural waste as a bio-resource in circular bioeconomy Bioresources in circular bioeconomy Algae as bio-resource in circular economy Circular economy for better tomorrowa Mango: nutrition, bioactive compounds and use Shea butter (karite): Nutrition and bioactive compounds Cashew: nutrition, cultivation and use Pineapple — nutrition and bioactive compounds Macadamia nut products, nutrition, and more How about avocado Healthy food with nutritious moringa Moringa in animal feed Moringa in natural cosmetics Moringa: a gift from nature Source Africa webpage: https://www.source-africa.com Interesting links Alg-AD — Creating value from waste nutrients by integrating algal and anaerobic digestion technology AlgaeBioGas — Algal treatment of biogas digestate with significant economic and environmental benefits for biogas plants operators Algen, algal technology centre, llc All-Gas project EABA — European Algal Biomass Association Frontiers in Marine Science — Research Topic: Boosting the Potential of Algae for Biomass Production, Valorisation, and Bioremediation Life AlgaeCan — Adding sustainability to the fruit and vegetable processing industry through solar-powered algal wastewater treatment SABANA — Sustainable algae biorefinery for agriculture and aquaculture Water2Return — Ecovery and REcycling of nutrients TURNing wasteWATER into added-value products for a circular economy in agriculture 23 Ljubljana . Stuttgart . Boston . Tbilisi 24