1. Y5C10 ENTREPRENEURSHIP IN
MICROBIOLOGY
Unit – IV Production of biodegradable plastic
Dr. S. Sivasankara Narayani
Assistant Professor
Department of Microbiology
Ayya Nadar Janaki Ammal College
Sivakasi, TamilNadu, India 08-10-2020Dr.SS

2. Unit IV
Mass cultivation: Phosphate solubilizer (Bacillus sp.) – macroalgae - bio-control
agents (Bio-pesticide). Preparation of probiotic feed - backers yeast -
development of vaccine -Production of growth factors. Preparation of
microbiological readymade Media and their ingredients. Production of
degradable plastics. Organic farming.
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3. • About 140 million tons of plastic are consumed every year worldwide, which
necessitates the processing of approximately 150 million tons of fossil fuels
and directly causes immense amounts of waste that can take thousands of
years to naturally deteriorate, if it degrades at all .
• Consequently, bioplastics are a feasible alternative in that they are not based
on fossil resources and can easily be biodegraded.
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4. • Plastics derived from crude oil(such as petroleum) rely more on scarce fossil
fuels.
• When plastics made from petroleum are burned, they release the carbon
dioxide contained in the petroleum into the atmosphere, leading to global
warming.
• Due to lack of proper disposal of these plastics, these effect wild life and
aquatic life
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5. • Bioplastics are a form of plastics derived from renewable biomass sources,
such as vegetable fats and oils, corn starch, pea starch or microbiota.
• some of these are…thermoplastic starch, Polylactic acid (PLA) plastics,
Poly-3-hydroxybutyrate (PHB)
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6. • Trends Global Production of bioplastics was 1.5 million tonnes by 2011. up
from 262,000 tonnes in 2007. (European Bioplastics)
• Production Capacity of bio-based plastics is projected to increase from
360,000 tonnes in 2007 to about 2.3 MILLION tonnes by 2013. (European
Bioplastics)
• Bioplastics will still only be 1.5% of the approximate 150 million tonnes of
plastics will be in use.
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7. • Some are stiff and brittle.
• Some are rubbery and moldable.
• Properties may be manipulated by blending polymers or genetic modifications.
• Degrades at 185°C.
• Moisture resistant, water insoluble, optically pure, impermeable to oxygen.
• Must maintain stability during manufacture and use but degrade rapidly when
disposed of or recycled
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8. • Bioplastics are designed to biodegrade. Bioplastics which are designed to
biodegrade can break down in either anaerobic or aerobic environments,
depending on how they are manufactured.
• Bioplastics are environmentally friendly because their production results in
the emission of less carbon dioxide, which is thought to cause global
warming.
• They are also biodegradable, meaning that the material returns to its
natural state when buried in the ground.
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9. • Starch-based plastics constituting about 50 percent of the bioplastics market,
thermoplastic starch, currently represents the most widely used bioplastic.
• Pure starch possesses the characteristic of being able to absorb humidity,
therefore Flexibiliser and plasticiser such as sorbitol and glycerine are added
so the starch can also be processed thermo-plastically.
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10. Cellulose-based plastics
• Cellulose bioplastics are mainly the cellulose esters, (including cellulose
acetate and nitrocellulose) and their derivatives, including celluloid.
• Some aliphatic polyesters The aliphatic biopolyesters are mainly
polyhydroxyalkanoates (PHA), poly-3-hydroxybutyrate (PHB), Polylactic acid
(PLA) plastics etc.
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11. Polylactic acid (PLA)
• Polylactic acid (PLA) is a transparent plastic produced from cane sugar or
glucose.
• Enzymes are used to break starch in the plants down into glucose, which is
fermented and made into lactic acid.
• This lactic acid is polymerized and converted into a plastic called polylactic
acid.
• These are used in the plastic processing industry for the production of foil,
moulds, cups and bottles.
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12. Poly-3-hydroxybutyrate (PHB)
• The biopolymer poly-3-hydroxybutyrate (PHB) is a polyester produced by certain bacteria
processing glucose, corn starch or wastewater.
• It produces transparent film at a melting point higher than 130 degrees Celsius, and is
biodegradable without residue.
• 3. Polyhydroxyalkanoates(PHA) These are linear polyesters produced in nature by bacterial
fermentation of sugar .
• They are produced by the bacteria to store carbon and energy.
• In industrial production, the polyester is extracted and purified from the bacteria by
optimizing the conditions for the fermentation of sugar.
• These plastics are being widely used in the medical industry.
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13. Bio-derived polyethylene
• The basic building block of polyethylene is ethylene.
• This is just one small chemical step from ethanol, which can be produced by
fermentation of agricultural feedstock's such as sugar cane or corn.
• Bio-derived polyethylene is chemically and physically identical to traditional
polyethylene – it does not biodegrade but can be recycled.
• It can also considerably reduce greenhouse gas emissions. It is used in
packaging such as bottles and tubs
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14. Production process for polylactic acid (PLA
• PLA is the most common bioplastic in use today.
• First, corn or other raw materials are fermented to produce lactic acid, which
is then polymerized to make PLA.
• Bioplastics are expected to make major contributions to environmental
protection, because they reduce CO2 and because they are biodegradable.
• The range of applications for bioplastics is growing, from materials used in
automobile interiors to packaging for foods and cosmetics, to agricultural
sheeting, to household appliances
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15. • There are two methods for manufacturing PLA from lactic acid:
• the first method uses the cyclic lactic acid dimer called lactide as an
intermediate stage;
• the second method is direct polymerization of lactic acid. The method using
the lactide intermediary yields PLA with greater molecular weight
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16. Uses of Bioplastic
• In electronic industries
1. Mitsubishi Plastics has already succeeded in raising the heat-resistance and strength
of polylactic acid by combining it with other biodegradable plastics and filler, and the
result was used to make the plastic casing.
2. NEC Corp., meanwhile, is turning its attention to kenaf, a type of fibrous plant
native to tropical areas of Africa and Asia that is known to grow more than five meters
in just half a year.
• A mixture of polylactic acid and kenaf fibre that is 20% fibre by weight allows for a
plastic that is strong enough and heat resistant enough to be used in electronic
goods.
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17. Packaging
• 1. The use of bioplastics for shopping bags is already very common.
• 2. After their initial use they can be reused as bags for organic waste and
then be composted.
• 3. Trays and containers for fruit, vegetables, eggs and meat, bottles for soft
drinks and dairy products and blister foils for fruit and vegetables are also
already widely manufactured from bioplastics.
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18. Catering products
• 1. Catering products belong to the group of perishable plastics.
• 2. Disposable crockery and cutlery, as well as pots and bowls, pack foils for
hamburgers and straws are being dumped after a single use, together with
food-leftovers, forming huge amounts of waste, particularly at big events.
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19. Gardening
• 1. Within the agricultural economy and the gardening sector mulch foils
made of biodegradable material and flower pots made of decomposable
bioplastics are predominantly used due to their adjustable lifespan and the
fact that these materials do not leave residues in the soil.
• 2. This helps reduce work and time (and thus cost) as these products can
simply be left to decompose, after which they are ploughed in to the soil.
• 3. Plant pots used for flowering and vegetable plants can be composted
along with gardening and kitchen litter
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20. Medical Products
• 1. In comparison to packaging, catering or gardening sectors, the medical
sector sets out completely different requirements with regards to products
made of renewable and reabsorbing plastics.
• 2. The highest possible qualitative standards have to be met and guaranteed,
resulting in an extremely high costs, which sometimes exceed 1.000 Euro per
kilo.
• 3. The potential applications of biodegradable or reabsorbing bioplastics are
manifold.
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21. Sanitary Products
• 1. Due to their specific characteristics, bioplastics are used as a basis for the
production of sanitary products.
• 2. These materials are breathable and allow water vapour to permeate, but at
the same time they are waterproof.
• 3. Foils made of soft bioplastic are already used as diaper foil, bed underlay,
for incontinence products, ladies sanitary products and as disposable gloves
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22. • Fastest in anaerobic sewage and slowest in seawater
• Depends on temperature, light, moisture, exposed surface area, pH and
microbial activity
• Degrading microbes colonize polymer surface & secrete PHA
depolymerases
• PHA CO2 + H2O (aerobically)
• PHA CO2 + H2O + CH4 (anaerobically
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23. • 15g starch
• 100 ml water
• Hot plate and heat
• 10 ml of glycerine
• Pour solution on aluminium foil
• Allowed dry for three days
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24. Questions to think
• Bioplastics
• What are types of bioplastics
• Benefits of bioplastics
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25. Clarifications
sivasan91@gmail.com
Sivasan_sf549@anjaconline.org
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26. 08-10-2020Dr.SS