Environmental biotechnology: A new era

Earth’s environment comprises of four major components i.e., Atmosphere, lithosphere, hydrosphere and biosphere. The atmosphere implies the protective blanket of gases, surrounding the earth. It absorbs most of the cosmic rays from outer space and a major portion of the electromagnetic radiation from the sun. The Hydrosphere comprises all types of water resources oceans, seas, lakes, rivers, streams, reservoir, polar icecaps, glaciers, and ground water. 97% of the earth’s water supply is in the oceans. About 2% of the water resources is locked in the polar icecaps and glaciers. Only about 1% is available as fresh surface water-rivers, lakes streams. Ground water also fit to be used for human consumption and other uses. Lithosphere is the outer mantle of the solid earth. It consists of minerals occurring in the earth’s crusts and the soil e.g., minerals, organic matter, air and water. Biosphere comprises the living organisms and their interactions with environment, viz atmosphere, hydrosphere and lithosphere.

Environmental biotechnology is the branch of biotechnology that caters to the issues pertaining to the environment including all the four components i.e., hydrosphere, lithosphere, atmosphere and biosphere. Environmental biotechnology specifically deals with the issues of atmosphere and hydrosphere.  It is the branch of biotechnology that resolves the environmental issues (pollution remediation, biofuel production, converting waste material into useful products, etc) through the usage of wild type or modified microbes and plants.

The International Society for Environmental Biotechnology defines environmental biotechnology as:

“The development, use and regulation of biological systems for remediation of contaminated environments (land, air, water), and for environment-friendly processes.”

• Green manufacturing technologies and sustainable development.
• Bioaccumulation
• Biodegradation
• Bioremediation
• Bioleaching
• Biomethanation

 

Role of environmental biotechnology

Environmental biotechnology plays a major role in environmental remediation through multiple ways. Technological advancements have paved many ways through which the environment could be fixed and made a better place to live in (Gavrilescu, M. ,2010). Some of them are as follows:

1. Bioremediation: Bioremediation is a natural process through which living organisms are employed, primarily yeast, algae, fungi and bacteria, decompose hazardous substances into something less toxic to the environment and to people. Specific parameters can be manipulated during the process to ensure optimum rates of degradation (Kalogerakis, N., Arff, J., Banat, I. M., Broch., 2015). There are three different types of bioremediations:

1)      Mycoremediation

2)      Microbial remediation

                  3)    Phytoremediation

  

            1. Mycoremediation: This method employs certain enzymes and fungi for the decontamination and sterilization of water and wetlands.

       2. Microbial remediation: In this approach, toxin loving organisms are exploited to cleanse and detoxify a certain environment component. The microbes utilize toxins as a source of food to gain energy for their metabolic processes.

3.    3.Phytoremediation:In this method, plants and different flora are utilized to detoxify water and land by trapping the toxins within their systems.

Bioremediation practices include:

• Waste water treatment
• Soil bioremediation
• Solid waste bioremediation
• Biotreatment of gaseous streams
• Biodegradation of hydrocarbons
• Biosorption

Advantages of Bioremediation:

• It is considered cheap as compared to multiple different technologies.
• Bioremediation being an all-natural process is perceived positively by the general public as compared to other methods.
• The methods employed in bioremediation are considered effective for the complete destruction of contaminants.
• Carried out in situ for most applications with no dangerous transport.
• Quick turnaround time to make soil and water useful.
• Minimal equipment needed except for specialized pieces (Azubuike, C. C., Chikere, C. B., & Okpokwasili, G. C. 2016)

Factors For Effective Microbial Bioremediation

 

• Microbial Population: Suitable kinds of microorganisms that can biodegrade all types of contaminants. (Srivastava, J., Naraian, R., Kalra, 2014)

• Oxygen: Oxygen should be enough to support aerobic biodegradation (about 2% oxygen in the gas phase or 0.4 mg/litre in the soil or water). (Srivastava, J., Naraian, R., Kalra, 2014)

• Water: Soil moisture should be from 50–70% of the water holding capacity of the soil (if bioremediation of contaminated soil is taken as an example). (Srivastava, J., Naraian, R., Kalra, 2014)

• Nutrients: Nitrogen, phosphorus, sulphur, and other nutrients to support good microbial growth. (Srivastava, J., Naraian, R., Kalra, 2014)
• Temperature: Appropriate temperatures for microbial growth, something between 0–40˚C. (Srivastava, J., Naraian, R., Kalra, 2014)
• pH: The Best range of pH should be around 6.5 to 7.5 to ensure good microbial growth and timely biodegradation. (Srivastava, J., Naraian, R., Kalra, 2014)

1.     2.Wastewater treatment: Wastewater is water that has been contaminated to the degree that it is no longer beneficial, and therefore must be treated before it can be used or released back into the environment. (Grady Jr, C. L., Daigger, G. T., Love, 2011)

Four major types of wastewater are

1.Domestic/Municipal wastewater

2. Industrial

3. Urban runoff and

4. Agricultural runoff

Pretreatment:

 

Primary treatment:

Secondary treatment:

 

Tertiary treatment:

Environmental biotechnology is the only way forward given the havoc that has been caused to the planet. The vast applications of environmental biotechnology including Industrial effluents neutralization, bioremediation, phytoremediation, conversion of waste into useful products, biofuel production and, waste water treatment. Environmental biotechnology plays key roles in the manufacture of new eco-friendly products, manufacture of conventional products in environmentally harmonious ways (Both goals reduce solids, liquids or gaseous waste outputs), clean-up of the residual effects of earlier human occupation, environmental biotechnology increases efficiency and productivity of existing biological systems, it alters the processes for the desired outcome(s). These vast applications, if implemented in an effective manner, provide hope for a better future of the planet and the upcoming generations.     

References:

1.      Gavrilescu, M. (2010). Environmental biotechnology: achievements, opportunities and challenges. Dynamic biochemistry, process biotechnology and molecular biology, 4(1), 1-36.

2.      Kalogerakis, N., Arff, J., Banat, I. M., Broch, O. J., Daffonchio, D., Edvardsen, T., ... & Fava, F. (2015). The role of environmental biotechnology in exploring, exploiting, monitoring, preserving, protecting and decontaminating the marine environment. New biotechnology, 32(1), 157-167.

3.      Azubuike, C. C., Chikere, C. B., & Okpokwasili, G. C. (2016). Bioremediation techniques–classification based on site of application: principles, advantages, limitations and prospects. World Journal of Microbiology and Biotechnology, 32(11), 1-18.

4.      Srivastava, J., Naraian, R., Kalra, S. J. S., & Chandra, H. (2014). Advances in microbial bioremediation and the factors influencing the process. International Journal of environmental science and technology, 11(6), 1787-1800.

5.      Grady Jr, C. L., Daigger, G. T., Love, N. G., & Filipe, C. D. (2011). Biological wastewater treatment. CRC press.

 

By: Areesha Ameem