lecture 15

Question 1

biomass

Answer 1

Biomass is the total dry organic matter or stored energy content of living or recently living organisms. Biomass can be used for fuel directly by burning it, indirectly by fermentation to an alcohol, or extraction of combustible oils. Biomass also includes biodegradable wastes that can be burnt as fuel

Question 2

Biofuel

Answer 2

Biofuel is a fuel that is derived from biomass. It is a renewable energy source; the CO2 released when it is burnt was absorbed from the atmosphere during plant growth.
Biofuel is made with ethanol which is produced by fermenting and then distilling starch and sugar crops such as maize, sorghum, potatoes, cassava, wheat, sugar cane and even fruit and vegetable waste.
Bioethanol is an alternative to petrol and can be made from sugar cane, maize or wheat. It can also be made from waste straw, willow and poplar trees, sawdust, various grasses, jerusalem artichoke, miscanthus and sorghum plants.
It can be produced from vegetable oils - principally rapeseed, oil palm and soya bean - animal oils and fats, tallow and waste cooking oil. It can also be produced from algae.

Question 3

types of biofuel

Answer 3

• Bio ethanol
• Bio butanol
• Bio diesel
• Biogas
• Hydrogen fuel

Question 4

Bioethanol

Answer 4

conversion of feedstock crop into fermentable sugars through enzyme amylase
Yeast is then added to ferment the sugars into alcohol and carbon dioxide
The main crop is used in biotheanol production varies throughout the world, Brazil is sugar can Elsa is corn ,Europe is wheat and barley

Question 5

Biobutanol

Answer 5

butanol is a 4-carbon alcohol

butanol is produced from biomass feedstocks
-butanols current primary use is as an industrial solvent in products such as lacquers and enamels
the properties of biobutanol make it highly amenable to blending with gasoline
-the energy content of biobutanol is 10-20% lower than that of gasoline

Question 6

Biodiesel

Answer 6

vegetable oil or animal fat based diesel consisting of long-chain alkyl esters
biodiesel is typically made oby chemically reacting lipids

Question 7

Biogas

Answer 7

gas produced by the biological breakdown of organic matter in the absence of oxygen

Question 8

Biogas

Answer 8

Biogas systems use bacteria to break down wet organic matter like animal dung, human sewage or food waste

produces methane, co2 and semi solid residue

Question 9

challenges of biofuels

Answer 9

• damages endangered habitats, accentuating their decline
• put food supplies at risk
• growing maize as feedstock for biofuels uses 30% more energy than the finished fuel provides

Question 10

Lipids of filamentous fungi as a material for producing biodiesel fuel

Answer 10

Species of various filamentous fungus taxa were tested for ability to produce lipids suitable as a material for manufacturing biodiesel.
The mucoralean fungus Cunninghamella japonica was found to be a promising lipid producer.
The heat of combustion of the lipids, 37.13 MJ/kg, was close to the value for rapeseed oil.

Question 11

protein engineering in designing tailored enzymes and microorganims for biofuels production

Answer 11

-Lignocellulosic biofuels = sustainable, renewable, and the only foreseeable alternative energy source to transportation fossil fuels.
- However, the recalcitrant nature of lignocellulose poses technical hurdles to an economically viable biorefinery.
Low enzymatic hydrolysis efficiency and low productivity, yield, and titer of biofuels are among the top cost contributors. Protein engineering has been used to improve the performance of lignocellulose-degrading enzymes, as well as proteins involved in biofuel synthesis pathways.

• Unlike its great success seen in other industrial applications, protein engineering has achieved only modest results in improving the lignocellulose- to-biofuels efficiency. This review will discuss the unique challenges that protein engineering faces in the process of converting lignocellulose to biofuels and how they are addressed by recent advances in this field.

Question 12

Hydrogenesis in hyperthermophilic microorganisms: Implications for biofuels. Metabolic Engineering.

Answer 12

Hydrothermal microbiotopes are characterized by the consumption and production of molecular hydrogen. Heterotrophic hyperthermophilic microorganisms (growth
Topt80 °C) actively participate in the production of H2 in these environments through the fermentation of peptides and carbohydrates. Hyperthermophiles have been shown to approach the theoretical (Thauer) limit of 4 mol of H2 produced per mole of glucose equivalent consumed, albeit at lower volumetric productivities than observed for mesophilic bacteria, especially enterics and clostridia.
Potential advantages for biohydrogen production at elevated temperatures include fewer metabolic byproducts formed, absence of catabolic repression for growth on heterogeneous biomass substrates, and reduced loss of H2 through conversion to H2S and CH4 by mesophilic consortia containing sulfate reducers and methanogens.
To fully exploit the use of these novel microorganisms and their constituent hydrogenases for biohydrogen production, development of versatile genetic systems and improvements in current understanding of electron flux from fermentable substrates to H2 in hyperthermophiles are needed.

Question 13

BIOREMEDIATION

Answer 13

USE OF LIVING ORGANISM FOR THE RECOVERY OF A CONTAMINATED MEDIUM

Question 14

Alaskan shoreline of Prince Williams Sound after the oil spill

Answer 14

The treatment of the Alaskan shoreline of Prince Williams Sound after the oil spill of Exxon Valdez in 1989 is one common example in which bioremediation methods got public attention

Question 15

GMO

Answer 15

Bioremediation using genetically engineered microorganisms (GEMs, or GMOs), carrying recombinant proteins, is still relatively uncommon due to regulatory constraints related to their release and control

Question 16

enzyme optimisation

Answer 16

Other methods of enzyme optimization that do not include gene cloning technqiues, might be applied to indigenous microorganisms in order to enhance their pre-existing traits.

Question 17

Nutrient

Answer 17

Nutrients added to the soil to enhance bacterial degradation of contaminants and increase the rate of bioremediation on the brownfield site

Question 18

intrinsic bioremediation

Answer 18

This process of bioremediation is also called as natural attenuation. It occurs in the soils and water which are contaminated with toxins. Microorganisms are involved in this type of bioremediation. Usually those contaminated sites are treated which are related with petroleum. As we all know that gas stations have underground tanks system which carries the petrol. If contamination or leakage occurs in these tanks then intrinsic bioremediation helps a lot. Microorganisms play an important role in this type and it is important to take precautionary measures so that the leaked oil does not affect the humans or does not cause pollution in the environment.

Question 19

bio stimulation

Answer 19

In this type of bioremediation, environment is modified by motivating the bacteria used for bioremediation. The experts release oxygen and other nutrients in the soil in which microorganisms are residing. These nutrients and oxygen are in the form of gas or liquid. Due to this the activity of the bacteria and other microorganisms flourishes and they remove contaminants from the environment or water more efficiently.

Question 20

Bioaugmentation

Answer 20

Sometimes microorganisms are needed to remove particular contaminants from the soil or water. Municipal waste water facilities use this type of bioremediation. This technique is not very successful because it is difficult for the scientists to control the growth of microorganisms for that particular contaminant.

Question 21

Phytoremediation

Answer 21

Phytoremediation is useful because natural plants or transgenic plants are able to bioaccumulate toxins in the above-ground parts, which are then harvested for removal

Question 22

mycoremediation

Answer 22

Mycoremediation is a form of bioremediation in which fungi are used
One of the primary roles of fungi in the ecosystem is decomposition. The mycelia secrete extracellular enzymes and acids that break down lignin and cellulose, the two main building blocks of plant s
The key to mycoremediation is determining the right fungal species to target a specific pollutant. Certain strains have been reported to successfully degrade the nerve gases VX and sarin
Mycofiltration is a similar or same process, using fungal mycelia to filter toxic waste and microorganisms from water in soil

Question 23

Microbiology of Composting

Answer 23

Composting involves different groups of microorganisms which act on the substrates in succession. Although the decomposition is mainly carried out by the thermophilic microorganisms, the initial process is carried out by mesophilic microorganisms.
At first the biodegradable materials, such as proteins and carbohydrates, are decomposed naturally by the mesophilic microorganisms. The degradation products are usually simple organic acids which causes a drop in pH. As the initial reactions proceed heat is produced which rises the temperature within the heap.
The thermophilic process has certain advantages as follows: - acceleration of the process
- killing of pathogenic microorganisms
-destruction of ungerminated seeds of weeds

Question 24

Role of Biotechnology in

Bioremediation

Answer 24

Biotechnology plays a vital role in the process of bioremediation because it provides natural mechanisms for the removal of contaminants from the environment, from water and soil
Biotechnology mechanisms are applied to bioremediation when the contaminants are composed if industrial wastes. Scientists are making efforts to produce microorganisms through genetic engineering techniques which will have higher metabolic activities and will be able to digest chemicals more efficiently
In situ developments in the bioremediation processes are possibly less in cost and they do not effect the environment in a negative way

Question 25

corynebacterium gllutamicaum

Answer 25

bacterium for bioremediation of arsenic

Question 26

Radioactive waste

Answer 26

The nuclear arms race generated thousands of disposal sites containing radioactive toxic wastes dumped into the ground. Bioremediation is regarded as a relatively cheap and effective way of cleaning up these sites; however, this will require microorganisms that can detoxify heavy-metal and organic pollutants while withstanding high doses of radiation
Brim et al. have demonstrated the feasibility of this strategy by genetically engineering microbes that can detoxify radioactive wastes with mixed compositions. They started with Deinococcus radiodurans—the most radiation-resistant organism yet known, and engineered it to express an Escherichia coli enzyme that converts ionic mercury to a less toxic form, and a Pseudomonas enzyme that breaks down toluene

Question 27

Genetic engineering

Answer 27

The use of genetic engineering to create organisms specifically designed for bioremediation has great potential. The bacterium Deinococcus radiodurans (the most radioresistant organism known) has been modified to consume and digest toluene and ionic mercury from highly radioactive nuclear waste.
The microbes are ever-present in any given context— generally referred to as “normal microbial flora”. During bioremediation (biodegradation) processes, fertilizers/nutrient supplementation is introduced to the environments, in efforts to maximize growth and production potential. Common misbelief is that microbes are transported and dispersed into an unadulterated environment.

Question 28

Cleaning up with genomics: applying molecular biology to bioremediation
Lovley (2003) Nature Reviews Microbiology 1, 35-44

Answer 28

Bioremediation has the potential to restore contaminated environments inexpensively yet effectively, but a lack of information about the factors controlling the growth and metabolism of microorganisms in polluted environments often limits its implementation. However, rapid advances in the understanding of bioremediation are on the horizon. Researchers now have the ability to culture microorganisms that are important in bioremediation and can evaluate their physiology using a combination of genome-enabled experimental and modelling techniques. In addition, new environmental genomic techniques offer the possibility for similar studies on as-yet-uncultured organisms. Combining models that can predict the activity of microorganisms that are involved in bioremediation with existing geochemical and hydrological models should transform bioremediation from a largely empirical practice into a science.

Question 29

Factors affecting bioremediation

Answer 29

1) molecular form
2) pH
3) nutrient availability
4) temperature
5) moisture
6) O2 concentrations
7) microbial community/ecology 8) other chemicals

Question 30

Other factors affecting bioremediation

Answer 30

Physiology of biodegradative microbes Metabolic processes
Scientific factors affecting bioremediation Energy sources
Bioavailability
Bioactivity and biochemistry Regulatory factors
Research and technical factors Human resource factor Economic and liability factor