Open access peer-reviewed chapter

Cyanobacteria for PHB Bioplastics Production: A Review

Written By

Erich Markl, Hannes Grünbichler and Maximilian Lackner

Submitted: March 20th, 2018 Reviewed: September 15th, 2018 Published: November 20th, 2018

DOI: 10.5772/intechopen.81536

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Edited by Yee Keung Wong

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Cyanobacteria, or blue-green algae, can be used as host to produce polyhydroxyalkanoates (PHA), which are promising bioplastic raw materials. The most important material thereof is polyhydroxybutyrate (PHB), which can replace the commodity polymer polypropylene (PP) in many applications, yielding a bio-based, biodegradable alternative solution. The advantage from using cyanobacteria to make PHB over the standard fermentation processes, with sugar or other organic (waste) materials as feedstock, is that the sustainability is better (compare first-generation biofuels with the feed vs. fuel debate), with CO2 being the only carbon source and sunlight being the sole energy source. In this review article, the state of the art of cyanobacterial PHB production and its outlook is discussed. Thirty-seven percent of dry cell weight of PHB could be obtained in 2018, which is getting close to up to 78% of PHB dry cell weight in heterotrophic microorganisms in fermentation reactors. A good potential for cyanobacterial PHB is seen throughout the literature.


  • polyhydroxybutyrate (PHB)
  • bioplastics
  • EN13432
  • biodegradability
  • organic carbon content
  • microplastics
  • cyanobacteria

1. Introduction

Bioplastics [1, 2, 3] are either biodegradable, e.g., according to the standard EN13432 [4], or at least partly made from renewable raw materials, e.g., according to ASTM D6866 [5]. Although their market share today is only approx. 2%, they see two-digit growth figures [6]. The sustainability of bioplastics is reviewed in [7]. Plastics in general and their composites are a large and important class of materials. The global production volume exceeds 300 million tons/year [8]. For a bioplastics material to have a major impact, it has to match the key properties of one of the commodity plastics such as PP, PE, PVC, PS or PET. This is the case with polyhydroxyalkanoates (PHA), which have the potential to replace mass polymer PP in many applications. Polyhydroxybutyrate (PHB) is the most important representative of PHA.

Cyanobacteria [9, 10, 11] are a phylum of bacteria that obtain their energy through photosynthesis, and they are the only photosynthetic prokaryotes that can produce oxygen. The name “cyanobacteria” is derived from the Greek word for “blue,” which is the color of cyanobacteria. Cyanobacteria are prokaryotes, and they are also called “blue-green algae,” though the term “algae” is not correct technically, as it only includes eukaryotes.

It was discovered that cyanobacteria can produce polyhydroxyalkanoates (PHA) photoautotrophically [12], with the potential for CO2 recycling and bioplastics production. This chapter is an up-to-date review on PHB production from cyanobacteria, since the last review article on this topic [13] was written already 5 years ago.


2. PHB, a commodity bioplastics for mass market products?

Today, thermoplastic starch (TPS) and polylactic acid (PLA) are the two dominant biodegradable bioplastics materials. Partly, bio-based PET (see, for example, the PlantBottle™ project) and “Green PE,” a polyethylene made from sugarcane-derived ethanol in Brazil, are the two most common nondegradable, but bio-based plastics. PHB has striking similarities to PP and has therefore been envisaged as potential replacement candidate for PP by Markl et al. [14], for instance, in biomedical, agricultural, and industrial applications [15]. The following Table 1 shows a comparison of PHB and PP.

Table 1.

Properties of PHB compared to those of PP (source: [16]).

The low elongation and break and the brittleness of PHB are limitations. These, however, can be overcome by using other PHA, blends of copolymers, see Table 2.

Table 2.

Property modification by copolymerization (source: [13]).

Apart from short-chain-length PHA, there are medium- and long-chain-length variants, too, [17], so that material properties can be tailored in a wide spectrum.

The majority of PP is used in short-lived plastic products such as rigid packaging, which partly end up in nature. A biodegradable alternative can be a sensible material solution. Since PHA can be selected and customized for various applications, and also blended, co-polymerized and compounded, it is estimated that up to 90% of all PP applications can be covered by PHA and to a large extent thereof by PHB. A disadvantage of PHB is its high production cost. In [15], ways to make PHA production more cost-competitive are listed (see Table 3).

Table 3.

Technology to be developed to lower PHA production cost (reproduced with permission from [15]).

Avoiding feedstock costs and using CO2 as sole carbon source are described as strong potential here.

In general, organic carbon feedstocks can yield high PHB contents in microorganisms. For instance, Bhati et al. produced 78% PHB of dry well weight with Nostoc muscorum Agardh [18].

An alternative production pathway for PHB is a catalytic one [19, 20]. Both the fermentation and the catalytic process yield an expensive PHB product, which is hard to sell as it competes with low-price commodities such as PE and PP for packaging applications, which are very cost-sensitive.


3. PHB production by cyanobacteria: current state of knowledge

It is known that cyanobacteria can produce PHB as an intracellular energy and carbon storage compound [21] (see Figure 1).

Figure 1.

PHB granules in cyanobacteria. Left: Wild type. Right: Mutant (reproduced with permission from [22]).

Reference [23] discusses the use of cyanobacteria to produce chemicals. Cyanobacteria show several industrially relevant benefits compared to their plant counterparts, including a faster growth rate, higher CO2 utilization and greater amenability to genetic engineering [24, 25].

Table 4 shows compounds that can be produced by cyanobacteria photoautotrophically [26].

Table 4.

Compounds that could be produced by cyanobacteria (reproduced with permission from [26]).

In 2013, a review on the production of poly-β-hydroxybutyrates from cyanobacteria for the production of bioplastics was published [13]. Meanwhile, significant improvements have been implemented.

In 2018, Troschl et al. could report 12.5% PHB cry well weight [21]. In the same year, Kamravamanesh et al. have shown that the cyanobacterium Synechocystis sp. PCC 6714 can produce up to 37% dry cell weight of PHB with CO2 as the only carbon source [27, 28], which is significantly above the other reported values from literature. The strain had been subjected to UV light mutations to increase the PHB productivity. Prior to that work, the thermophilic cyanobacterium, Synechococcus sp. MA19, was reported to have achieved 27% of dry cell weight PHB [29]. It was reported that, originally, the MA 19 was isolated from a hot spring in Japan (Miyakejima). However, neither the authors of this paper nor other researchers [30] were able to obtain a sample from that strain in 2016–2018, despite high efforts, so currently, Kamravamanesh’s strain Synechocystis sp. PCC 6714 can be considered the cyanobacterium with the highest PHB content. A high PHB content is advantageous for downstream processing in terms of energy efficiency, for instance, or product quality.

Genetic engineering is commonly deployed to increase the yield of PHB compared to wild types [26, 31, 32]. Also, bioprocess optimization is carried out [27, 28]. Growth is typically followed by nitrogen and/or phosphorous limitation. Also, “feast and famine” strategies concerning the carbon source are applied [33].

Reference [34] discusses the use of consortia of cyanobacteria and heterotrophic bacteria for stable PHB production.

The modeling of cyanobacterial PHB production is discussed in [35].

A possible growth system for PHB from cyanobacteria is presented in [18], see Figure 2 below.

Figure 2.

Operation mode for PHB production from cyanobacteria. The ripening tank is used for PHB production at a later stage, where no CO2 is consumed, but glycogen gets converted into PHB (reproduced with permission from [18]).

The study in [18] uses long-term, non-sterile cultivation of Synechocystis sp. CCALA192 in a tubular photobioreactor for PHB production. Another concept would be open pond photobioreactors like open pond raceways. Different photobioreactor setups are reviewed in [18, 36, 37, 38, 39]. A promising alternative is an integrated algae-based biorefinery, e.g., for the production of biodiesel, astaxanthin and PHB as presented by [40] or [41].


4. PHB production by cyanobacteria: an outlook

A major unsolved issue is the downstream processing of the cyanobacteria, i.e., how to get the bioplastics material out of the cyanobacteria (see Figure 3).

Figure 3.

Schematic illustration of factors impacting sustainability of PHA production (reproduced with permission from [42]).

In Ref. [23], photomixotrophic conditions to increase cyanobacterial production rate and yield are reviewed. Supplementation with fixed carbon sources gives additional carbon building blocks and energy to speed up production. Photomixotrophic production was found to increase titers up to fivefold over traditional autotrophic conditions [23], so there is a strong future potential in this mode for cyanobacteria.


5. Conclusions

This chapter has presented an update on PHB production by cyanobacteria, a process route which can be more sustainable than catalytic production from CO or fermentation from sugar compounds. It is expected that PHB and its compounds will gradually replace PP in many large volume applications. Genetic engineering can increase the yield of PHB in cyanobacteria; however, the downside is that approval for large-scale cultivation in (cost- and energy-efficient) open growth systems will be difficult to obtain in most countries, so technologies avoiding genetic engineering seem to be most promising for commercial development.



Financial support from Wirtschaftsagentur Wien is gratefully acknowledged.


Conflict of interest

The authors declare that they have no conflict of interest.


  1. 1. Lackner M. Bioplastics—Biobased plastics as renewable and/or biodegradable alternatives to petroplastics. In: Kirk-Othmer Encyclopedia of Chemical Technology. New York, USA: Wiley; 2015
  2. 2. Ashter SA. Introduction to Bioplastics Engineering. Oxford, UK: William Andrew; 2016. ISBN: 978-0323393966
  3. 3. Kabasci S, editor. Bio-Based Plastics: Materials and Applications. Weinheim, Germany: Wiley VCH; 2013. ISBN: 9781119994008
  4. 4. DIN EN 13432-2000. Packaging—Requirements for Packaging Recoverable Through Composting and Biodegradation—Test Scheme and Evaluation Criteria for the Final Acceptance of Packaging; German Version EN 13432:2000. Accessed: August 1, 2018
  5. 5. ASTM D6866-18. Standard Test Methods for Determining the Biobased Content of Solid, Liquid, and Gaseous Samples Using Radiocarbon Analysis. Accessed: August 1, 2018
  6. 6. Endres H-J. Engineering Biopolymers: Markets, Manufacturing, Properties and Applications. Munich, Germany: Hanser Pubn; 2010. ISBN: 978-1569904619
  7. 7. Thakur S, Chaudhary J, Sharma B, Verma A, Thakur VK. Sustainability of bioplastics: Opportunities and challenges. Current Opinion in Green and Sustainable Chemistry. 2018;13:68-75
  8. 8. Plastics Europe, The Facts 2017.
  9. 9. Sharma NK, Rai AK, Stal LJ. Cyanobacteria: An Economic Perspective. Malden, USA: Wiley-Blackwell; 2014. ISBN: 978-1119941279
  10. 10. Nienaber MA, Steinitz-Kannan M. A Guide to Cyanobacteria: Identification and Impact Kindle Edition. Lexington, USA: University Press of Kentucky; 2018. ISBN: 978-0813175591
  11. 11. Tiwari A. Cyanobacteria Nature, Potentials and Applications. Lexington, USA: Astral; 2014. ISBN-13: 978-8170359128
  12. 12. Asada Y, Miyake M, Miyake J, Kurane R, Tokiwa Y. Photosynthetic accumulation of poly-(hydroxybutyrate) by cyanobacteria—The metabolism and potential for CO2 recycling. International Journal of Biological Macromolecules. 1999;25(1-3):37-42
  13. 13. Balaji S, Gopi K, Muthuvelan B. A review on production of poly β hydroxybutyrates from cyanobacteria for the production of bio plastics. Algal Research. 2013;2(3):278-285
  14. 14. Markl E, Grünbichler H, Lackner M. PHB—Biobased and biodegradable replacement for PP: A review. Novel Techniques in Nutrition and Food Science (NTNF). 2018;2(4):1-4
  15. 15. Możejko-Ciesielska J, Kiewisz R. Bacterial polyhydroxyalkanoates: Still fabulous? Microbiological Research. 2016;192:271-282
  16. 16. Kaplan DL. Biopolymers from Renewable Resources. New York, USA: Springer; 1998. ISBN: 978-3540635673
  17. 17. Singh AK, Mallick N. Enhanced production of SCL-LCL-PHA co-polymer by sludge-isolated Pseudomonas aeruginosa MTCC 7925. Letters in Applied Microbiology. 2008;46(3):350-357. DOI: 10.1111/j.1472-765X.2008.02323.x
  18. 18. Bhati R, Mallick N. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer production by the diazotrophic cyanobacterium Nostoc muscorum Agardh: Process optimization and polymer characterization. Algal Research. 2015;7:78-85. DOI: 10.1016/j.algal.2014.12.003
  19. 19. Wang Y, Yin J, Chen G-Q. Polyhydroxyalkanoates, challenges and opportunities. Current Opinion in Biotechnology. 2014;30:59-65
  20. 20. Reichardt R, Rieger B. Poly(3-Hydroxybutyrate) from carbon monoxide. In: Rieger B, Künkel A, Coates GW, Reichardt R, Dinjus E, Zevaco TA, editors. Synthetic Biodegradable Polymers. New York, USA: Springer; 2012 ISBN 978-3-642-27154-0
  21. 21. Troschl C, Meixner K, Fritz I, Leitner K, Drosg B. Pilot-scale production of poly-β-hydroxybutyrate with the cyanobacterium Synechocystis sp. CCALA192 in a non-sterile tubular photobioreactor. Algal Research. 2018;34:116-125
  22. 22. Damrow R, Maldener I, Zilliges Y. The multiple functions of common microbial carbon polymers, glycogen and PHB, during stress responses in the non-diazotrophic cyanobacterium Synechocystis sp. PCC 6803. Frontiers in Microbiology. 2016;7:966. DOI: 10.3389/fmicb.2016.00966
  23. 23. Matson MM, Atsumi S. Photomixotrophic chemical production in cyanobacteria. Current Opinion in Biotechnology. 2018;50:65-71
  24. 24. Field CB, Behrenfeld MJ, Randerson JT, Falkowski P. Primary production of the biosphere: Integrating terrestrial and oceanic components. Science. 1998;281:237-240
  25. 25. Heidorn T, Camsund D, Huang HH, Lindberg P, Oliveira P, Stensjo K, et al. Synthetic biology in cyanobacteria engineering and analyzing novel functions. Methods in Enzymology. 2011;497:539-579
  26. 26. Carroll AL, Case AE, Zhang A, Atsumi S. Metabolic engineering tools in model cyanobacteria. Metabolic Engineering. In press, corrected proof, Available online 26 March 2018
  27. 27. Kamravamanesh D, Pflügl S, Nischkauer W, Limbeck A, Lackner M, Herwig C. Photosynthetic poly-β-hydroxybutyrate accumulation in unicellular cyanobacterium Synechocystis sp. PCC 6714. AMB Express. 2017;7(1):143. DOI: 10.1186/s13568-017-0443-9. Epub 2017 Jul 6
  28. 28. Kamravamanesh D, Pflügl S, Kovacs T, Druzhinina I, Kroll P, Maximilian L, et al. Increased poly-beta-hydroxybutyrate production from CO2 in randomly mutated cells of cyanobacterial strain Synechocystis sp. PCC 6714: Mutant generation and characterization. Bioresource Technology. 2018;266:34-44. DOI: 10.1016/j.biortech.2018.06.057
  29. 29. Miyake M, Erata M, Asada Y. A thermophilic cyanobacterium, Synechococcus sp. MA19, capable of accumulating poly-β-hydroxybutyrate. Journal of Fermentation and Bioengineering. 1996;82(5):512-514
  30. 30. Fritz I. Universität für Bodenkultur Wien. BOKU, University of Natural Resources and Life Sciences, Vienna, Private Communication. 2018
  31. 31. Hondo S, Takahashi M, Osanai T, Matsuda M, Asayama M. Genetic engineering and metabolite profiling for overproduction of polyhydroxybutyrate in cyanobacteria. Journal of Bioscience and Bioengineering. 2015;120(5):510-517
  32. 32. Angermayr SA, Gorchs Rovira A, Hellingwerf KJ. Metabolic engineering of cyanobacteria for the synthesis of commodity products. Trends in Biotechnology. 2015;33(6):352-361
  33. 33. Arias DM, Fradinho JC, Uggetti E, García J, Reis MAM. Polymer accumulation in mixed cyanobacterial cultures selected under the feast and famine strategy. Algal Research. 2018;33:99-108
  34. 34. Weiss TL, Young EJ, Ducat DC. A synthetic, light-driven consortium of cyanobacteria and heterotrophic bacteria enables stable polyhydroxybutyrate production. Metabolic Engineering. 2017;44:236-245
  35. 35. Carpine R, Raganati F, Olivieri G, Hellingwerf KJ, Marzocchella A. Poly-β-hydroxybutyrate (PHB) production by Synechocystis PCC6803 from CO2: Model development. Algal Research. 2018;29:49-60
  36. 36. Diehl S, Zambrano J, Carlsson B. Analysis of photobioreactors in series. Mathematical Biosciences. In press, accepted manuscript, Available online 27 July 2018
  37. 37. Wolf J, Stephens E, Steinbusch S, Yarnold J, Hankamer B. Multifactorial comparison of photobioreactor geometries in parallel microalgae cultivations. Algal Research. 2016;15:187-201
  38. 38. Perez-Castro A, Sanchez-Moreno J, Castilla M. PhotoBioLib: A Modelica library for modeling and simulation of large-scale photobioreactors. Computers & Chemical Engineering. 2017;98:12-20
  39. 39. Acién FG, Molina E, Reis A, Torzillo G, Masojídek J. Photobioreactors for the production of microalgae. In: Microalgae-Based Biofuels and Bioproducts. Duxford, UK: Woodhead Publishing; 2017. pp. 1-44
  40. 40. García Prieto CV, Ramos FD, Estrada V, Villar MA, Soledad Diaz M. Optimization of an integrated algae-based biorefinery for the production of biodiesel, astaxanthin and PHB. Energy. 2017;139(15):1159-1172
  41. 41. Meixner K, Kovalcik A, Sykacek E, Gruber-Brunhumer M, Drosg B. Cyanobacteria biorefinery—Production of poly(3-hydroxybutyrate) with Synechocystis salina and utilisation of residual biomass. Journal of Biotechnology. 2018;265:46-53
  42. 42. Koller M, Maršálek L, de Sousa Dias MM, Braunegg G. Producing microbial polyhydroxyalkanoate (PHA) biopolyesters in a sustainable manner. New Biotechnology. 2017;37(Part A):24-38. DOI: 10.1016/j.nbt.2016.05.001

Written By

Erich Markl, Hannes Grünbichler and Maximilian Lackner

Submitted: March 20th, 2018 Reviewed: September 15th, 2018 Published: November 20th, 2018