Natural plasmids have been found from alkaliphiles, but their exploitation has not
yet been wide. May be plasmids have a role in the pH adaptation like that of lactic
acid bacteria? The enzymes found from alkaliphiles have been usually cloned and
expressed in standard neutral-growing host organisms. The motivation for the efforts
for metabolic engineering in alkaliphiles would increase when industrially feasible
unique metabolites will be found from alkaliphiles. Expression of monomers for
biopolymers, like bioplastics, and specialty chemicals, is a potential field for genetic
engineering. Even if the basic metabolism of alkaliphiles has not yet demonstrated
exceptional principal differences compared to that of neutralophiles, it still needs to
be considered that only a minor part of alkaliphiles has been relatively studied in
detail. Bioinformatics and fast sequencing will, undoubtedly, allow the emergence of
new discoveries soon. These questions will be dealt with in detail in other chapters in
this book.
3 Bioplastics
Bioplastics are biopolymers, the name referring to plasticity of a material. Plastics
can be molded to hard or flexible forms like mulches, bottles, utensils, parts of
machines, construction materials, foams, and so on. The industry is so vast and
established that existing practices are not easy to change. The term bioplastic
involves several meanings which are not always recognized. The term can be used
for plastics made of renewable biological materials. They may or may not be
biodegradable. If not, they are called durable. Durable (bio- or oil-based) plastics
can break down to small particles but may practically never disappear from nature,
and those micro- and nanoparticles are widely recognized as a serious threat for life
on earth. If the cycling of plastics is not perfect, as seems to be the fact in the real life,
it means that the nature will be increasingly polluted with small particles of durable
plastics. That process will continue hundreds of years even after dumping of the
plastics is stopped. The composites of biodegradable and durable plastics have
also been produced. These composites seemingly disappear rather fast, but the
microscopic durable particles stay in soil. Thus, such composites are, even in a
short period, more dangerous to nature and human health than durable plastic. For
recycling, it is important to be able to divide the waste plastics into biodegradable
and durable fractions. The sustainable long-term solution may be to use fully
biodegradable plastics. The current problem related to the use of biodegradable
plastic is high price and sometimes the nonoptimal mechanical properties. The
European Commission is presently formulating its plastics strategy wherein different
measures will be included to avoid drawbacks made by plastics (https://www.
european-bioplastics.org). As can be seen from the European dialogues on plastics,
the question is not black-and-white. EU, however, recognizes the benefits of
bioplastics. The production of bioplastics is highly energy-consuming, and therefore, its circulation back to industry shall be organized. Whatsoever, biodegradable
bioplastics will be extremely big business in the future and also attractive topic to
Metabolites Produced by Alkaliphiles with Potential Biotechnological. . .
165
yet been wide. May be plasmids have a role in the pH adaptation like that of lactic
acid bacteria? The enzymes found from alkaliphiles have been usually cloned and
expressed in standard neutral-growing host organisms. The motivation for the efforts
for metabolic engineering in alkaliphiles would increase when industrially feasible
unique metabolites will be found from alkaliphiles. Expression of monomers for
biopolymers, like bioplastics, and specialty chemicals, is a potential field for genetic
engineering. Even if the basic metabolism of alkaliphiles has not yet demonstrated
exceptional principal differences compared to that of neutralophiles, it still needs to
be considered that only a minor part of alkaliphiles has been relatively studied in
detail. Bioinformatics and fast sequencing will, undoubtedly, allow the emergence of
new discoveries soon. These questions will be dealt with in detail in other chapters in
this book.
3 Bioplastics
Bioplastics are biopolymers, the name referring to plasticity of a material. Plastics
can be molded to hard or flexible forms like mulches, bottles, utensils, parts of
machines, construction materials, foams, and so on. The industry is so vast and
established that existing practices are not easy to change. The term bioplastic
involves several meanings which are not always recognized. The term can be used
for plastics made of renewable biological materials. They may or may not be
biodegradable. If not, they are called durable. Durable (bio- or oil-based) plastics
can break down to small particles but may practically never disappear from nature,
and those micro- and nanoparticles are widely recognized as a serious threat for life
on earth. If the cycling of plastics is not perfect, as seems to be the fact in the real life,
it means that the nature will be increasingly polluted with small particles of durable
plastics. That process will continue hundreds of years even after dumping of the
plastics is stopped. The composites of biodegradable and durable plastics have
also been produced. These composites seemingly disappear rather fast, but the
microscopic durable particles stay in soil. Thus, such composites are, even in a
short period, more dangerous to nature and human health than durable plastic. For
recycling, it is important to be able to divide the waste plastics into biodegradable
and durable fractions. The sustainable long-term solution may be to use fully
biodegradable plastics. The current problem related to the use of biodegradable
plastic is high price and sometimes the nonoptimal mechanical properties. The
European Commission is presently formulating its plastics strategy wherein different
measures will be included to avoid drawbacks made by plastics (https://www.
european-bioplastics.org). As can be seen from the European dialogues on plastics,
the question is not black-and-white. EU, however, recognizes the benefits of
bioplastics. The production of bioplastics is highly energy-consuming, and therefore, its circulation back to industry shall be organized. Whatsoever, biodegradable
bioplastics will be extremely big business in the future and also attractive topic to
Metabolites Produced by Alkaliphiles with Potential Biotechnological. . .
165