Examples of these HAs include 4HB (Taguchi et al. 2012), 3HHx (Taguchi et al.
2012), 3H4MV(Tanadchangsaeng et al. 2009, 2010; Saika et al. 2015), and others
(Matsusaki et al. 2000; Hiroe et al. 2016; Mizuno et al. 2014) listed in Table 3.4.
Incorporation of a small amount of the second monomer unit from longer-chain HAs
is enough to increase their flexibility. Interestingly, P(3HB-co-6 mol% 3HA)
(Matsusaki et al. 2000) copolymer shows almost mechanical properties to
low-density polyethylene; thus, it holds a wider opportunity to be exploited for
various applications.
3.4
Remarks and Outlook
Significant human activities have created overdependence on PBP, owing to its
versatility. Nevertheless, the existing situation is not sustainable and imposes a
serious threat to the environment. The similitude possesses by PHA to serve as an
alternative to PBP will be beneficial in circumventing this issue. Additionally, unlike
PBP, PHA is able to degrade in the environment such as under composting and
marine which can prevent microplastic pollution. On top of it, the use of PHA-based
biomaterials can help to reduce the amount of waste produced from agricultural,
industrial, and domestic. A myriad of microorganisms convert these waste materials
into PHA. However, PHA has several limitations in getting it commercialized; thus,
more improvement are required to diversify applications related to PHA. Comprehensive studies are needed to improve the material properties and the productivity of
PHA to make it competitive to PBP. Considering the rapid increase in the development of PHA-related researches, it can be expected that PHA can get
commercialized in a few decades ahead. Alongside, positive perceptions toward
the use of eco-friendly material can help to dot PHA in the commercial market as
expected.
References
Akiyama M, Taima Y, Doi Y (1992) Production of poly(3-hydroxyalkanoates) by a bacterium of
the genus Alcaligenes utilizing long-chain fatty acids. Appl Microbiol Biotechnol 37
(6):698–701
Akiyama M, Tsuge T, Doi Y (2003) Environmental life cycle comparison of
polyhydroxyalkanoates produced from renewable carbon resources by bacterial fermentation.
Polym Degrad Stab 80(1):183–194
Albuquerque MGE, Torres CAV, Reis MAM (2010) Polyhydroxyalkanoate (PHA) production by a
mixed microbial culture using sugar molasses: effect of the influent substrate concentration on
culture selection. Water Res 44(11):3419–3433
Anderson AJ, Dawes EA (1990) Occurrence, metabolism, metabolic role, and industrial uses of
bacterial polyhydroxyalkanoates. Microbiol Mol Biol Rev 54(4):450–472
Antonio RV, Steinbüchel A, Rehm BH (2000) Analysis of in vivo substrate specificity of the PHA
synthase from Ralstonia eutropha: formation of novel copolyesters in recombinant Escherichia
coli. FEMS Microbiol Lett 182(1):111–117
3 Development of Polyhydroxyalkanoate (PHA) and Its Copolymers as a Possible. . .
75
2012), 3H4MV(Tanadchangsaeng et al. 2009, 2010; Saika et al. 2015), and others
(Matsusaki et al. 2000; Hiroe et al. 2016; Mizuno et al. 2014) listed in Table 3.4.
Incorporation of a small amount of the second monomer unit from longer-chain HAs
is enough to increase their flexibility. Interestingly, P(3HB-co-6 mol% 3HA)
(Matsusaki et al. 2000) copolymer shows almost mechanical properties to
low-density polyethylene; thus, it holds a wider opportunity to be exploited for
various applications.
3.4
Remarks and Outlook
Significant human activities have created overdependence on PBP, owing to its
versatility. Nevertheless, the existing situation is not sustainable and imposes a
serious threat to the environment. The similitude possesses by PHA to serve as an
alternative to PBP will be beneficial in circumventing this issue. Additionally, unlike
PBP, PHA is able to degrade in the environment such as under composting and
marine which can prevent microplastic pollution. On top of it, the use of PHA-based
biomaterials can help to reduce the amount of waste produced from agricultural,
industrial, and domestic. A myriad of microorganisms convert these waste materials
into PHA. However, PHA has several limitations in getting it commercialized; thus,
more improvement are required to diversify applications related to PHA. Comprehensive studies are needed to improve the material properties and the productivity of
PHA to make it competitive to PBP. Considering the rapid increase in the development of PHA-related researches, it can be expected that PHA can get
commercialized in a few decades ahead. Alongside, positive perceptions toward
the use of eco-friendly material can help to dot PHA in the commercial market as
expected.
References
Akiyama M, Taima Y, Doi Y (1992) Production of poly(3-hydroxyalkanoates) by a bacterium of
the genus Alcaligenes utilizing long-chain fatty acids. Appl Microbiol Biotechnol 37
(6):698–701
Akiyama M, Tsuge T, Doi Y (2003) Environmental life cycle comparison of
polyhydroxyalkanoates produced from renewable carbon resources by bacterial fermentation.
Polym Degrad Stab 80(1):183–194
Albuquerque MGE, Torres CAV, Reis MAM (2010) Polyhydroxyalkanoate (PHA) production by a
mixed microbial culture using sugar molasses: effect of the influent substrate concentration on
culture selection. Water Res 44(11):3419–3433
Anderson AJ, Dawes EA (1990) Occurrence, metabolism, metabolic role, and industrial uses of
bacterial polyhydroxyalkanoates. Microbiol Mol Biol Rev 54(4):450–472
Antonio RV, Steinbüchel A, Rehm BH (2000) Analysis of in vivo substrate specificity of the PHA
synthase from Ralstonia eutropha: formation of novel copolyesters in recombinant Escherichia
coli. FEMS Microbiol Lett 182(1):111–117
3 Development of Polyhydroxyalkanoate (PHA) and Its Copolymers as a Possible. . .
75