Prasanna

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Principles of Ecology

The term “ecology” (oekologie) is derived from two Greek words – oikos (meaning house or dwelling place and logos meaning study) It was first proposed by Reiter (1868). However, the most widely accepted defiition of ecology was given by Ernest Haeckel (1869).

Alexandar von Humbolt – Father of Ecology
Eugene P. Odum – Father of modern Ecology
R. Misra – Father of Indian Ecology

Definitions of ecology

“The study of living organisms, both plants and animals, in their natural habitats or homes.” – Reiter (1885)

“Ecology is the study of the reciprocal relationship between living organisms and their environment.” – Earnest Haeckel (1889)

Ecological hierarchy

The interaction of organisms with their environment results in the establishment of grouping of organisms which is called ecological hierarchy or ecological levels of organization.

The basic unit of ecological hierarchy is an individual organism. The hierarchy of ecological systems is illustrated below:

Branches of Ecology:

Ecology is mainly divided into two branches, they are autecology and synecology.

• Autecology is the ecology of an individual species and is also called species ecology.
• Synecology is the ecology of a population or community with one or more species and also called as community ecology.

Many advances and developments in the field ecology resulted in various new dimensions and branches. Some of the advanced fields are Molecular ecology, Eco technology, Statistical ecology and Environmental toxicology.

Habitat and Niche

Habitat

Habitat is a specifi physical place or locality occupied by an organism or any species which has a particular combination of abiotic or environmental factors. But the environment of any community is called Biotope.

Niche

An ecological niche refers to an organism’s place in the biotic environment and its functional role in an ecosystem. The term was coined by the naturalist Roswell Hill Johnson but Grinell (1917) was probably first to use this term. The habitat and niche of any organism is called Ecotope.

The differences between habitat and niche are as follows.

Ecological equivalents

Taxonomically diffrent species occupying similar habitats (Niches) in diffrent geographical regions are called Ecological equivalents.

Examples:

• Certain species of epiphytic orchids of Western Ghats of India differ from the epiphytic orchids of South America. But they are epiphytes.
• Species of the grass lands of Western Ghats of India differ from the grass species of temperate grass lands of Steppe in North America. But they are all ecologically primary producers and fulfiling similar roles in their respective communities.

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Future Biotechnology

Biotechnology has become a comprehensive scientific venture from the point of academic and commercial angles, within a short time with the sequencing of human genome and genome of some important organisms. The future developments in biotechnology will be exciting. Thus the development in biotechnology will lead to a new scientific revolution that would change the lives and future of people.

Like industrial and computer revolution, biotechnological revolution will also promise major changes in many aspects of modern life.

Biotechnology is also revolutionizing the diagnosis of diseases caused by genetic factors. New tests can detect changes in the DNA sequence of genes associated with disease risk and can predict the likelihood that a patient will develop a disease.

The ability of therapeutics and vaccines to treat and prevent diseases has been well documented. Biotechnology has been central to these advances, progressively offering the ability to make more complicated medicines and vaccines, opening up the treatment and prevention of a broader set of diseases.

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Intellectual Rights of Property (Ipr), Biosafety and Bioethics

Intellectual property right (IPR) is a category of rights that includes intangible creation of the human intellect, and primarily consists of copyrights, patents, and trademarks. It also includes other types of rights, such as trade secrets, publicity rights, moral rights, and rights against unfair competition.

In biotechnology, the transformed microorganisms and plants and technologies for the production of commercial products are exclusively the property of the discoverer. The discoverer has the full rights on his property. It should not be neglected by the others without legal permission.

The right of discoverer must be protected and it does by certain laws framed by a country. The IPR is protected by different ways like patents, copyrights, trade secrets and trademarks, designs and geographical indications.

Patents

It is a special right to the discoverer/inventor that has been granted by the government through legislation for trading new articles. A patent is a personal property which can be licensed or sold by the person or organisation just like any other property. Patent terms give the inventor the rights to exclude others from making, using or selling his invention.

Biosafety and Bioethics

Advances in biotechnology and their applications deals with genetic manipulation.

Biosafety

Biosafety is the prevention of large-scale loss of biological integrity, focusing both on ecology and human health. These prevention mechanisms include conduction of regular reviews of the biosafety in laboratory settings, as well as strict guidelines to follow. Many laboratories handling biohazards employ an ongoing risk management assessment and enforcement process for biosafety. Failures to follow such protocols can lead to increased risk of exposure to biohazards or pathogens.

Bioethics – Ethical, Legal and Social Implications (ELSI)

Bioethics refers to the study of ethical issues emerging from advances in biology and medicine. It is also a moral discernment as it relates to medical policy and practice. Bioethicists are concerned with the ethical questions that arise in the relationships among life sciences, biotechnology and medicine. It includes the study of values relating to primary care and other branches of medicine.

The scope of bioethics is directly related to biotechnology, including cloning, gene therapy, life extension, human genetic engineering, astroethics life in space, and manipulation of basic biology through altered DNA, RNA and proteins.

These developments in biotechnology will affect future evolution, and may require new principles, such as biotic ethics, that values life and its basic biological characters and structures. The Ethical, Legal, and Social Implications (ELSI) program was founded in 1990 as an integral part of the Human Genome Project.

The mission of the ELSI program was to identify and address issues raised by genomic research that would affect individuals, families, and society. A percentage of the Human Genome Project budget at the National Institutes of Health and the U.S. Department of Energy was devoted to ELSI research.

Genetic Engineering Appraisal Committee (GEAC)

GEAC is an apex body under Ministry of Environment, Forests and Climate change for regulating manufacturing, use, import, export and storage of hazardous microbes or genetically modifid organisms (GMOs) and cells in the country. It was established as an apex body to accord approval of activities involving large scale use of hazardous microorganisms and recombinants in research and industrial production.

The GEAC is also responsible for approval of proposals relating to release of genetically engineered organisms and products into the environment including experimental field trials.

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Conservation of Plant Genetic Resources

Germplasm Conservation

Germplasm conservation refers to the conservation of living genetic resources like pollen, seeds or tissue of plant material maintained for the purpose of selective plant breeding, preservation in live condition and used for many research works. Germplasm conservation resources is a part of collection of seeds and pollen that are stored in seed or pollen banks, so as to maintain their viability and fertility for any later use such as hybridization and crop improvement.

Germplasm conservation may also involve a gene bank, DNA bank of elite breeding lines of plant resources for the maintenance of biological diversity and also for food security.

Cryopreservation (- 195.C)

Cryopreservation, also known as Cryoconservation, is a process by which protoplasts, cells, tissues, organelles, organs, extracellular matrix, enzymes or any other biological materials are subjected to preservation by cooling to very low temperature of – 196°C using liquid nitrogen.

At this extreme low temperature any enzymatic or chemical activity of the biological material will be totally stopped and this leads to preservation of material in dormant status. Later these materials can be activated by bringing to room temperature slowly for any experimental work.

Protective agents like dimethyl sulphoxide, glycerol or sucrose are added before cryopreservation process. These protective agents are called cryoprotectants, since they protect the cells, or tissues from the stress of freezing temperature.

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Applications of Plant Tissue Culture

Plant tissue culture techniques have several applications such as:

• Improved hybrids production through somatic hybridization.
• Somatic embryoids can be encapsulated into synthetic seeds (synseeds). These encapsulated seeds or synthetic seeds help in conservation of plant biodiversity.
• Production of disease resistant plants through meristem and shoot tip culture.
• Production of stress resistant plants like herbicide tolerant, heat tolerant plants.
• Micropropagation technique to obtain large numbers of plantlets of both crop and tree species useful in forestry within a short span of time and all through the year.
• Production of secondary metabolites from cell culture utilized in pharmaceutical, cosmetic and food industries.

Micropropagation of Banana

Micropropagation of plants at industrial level maintains high standards of homogeneity in plants like pineapple, banana, strawberry and potato.

Artificial Seed

Artificial seeds or synthetic seeds (synseeds) are produced by using embryoids (somatic embryos) obtained through in vitro culture. They may even be derived from single cells from any part of the plant that later divide to form cell mass containing dense cytoplasm, large nuclceus, starch grains, proteins, and oils etc., To prepare the artifiial seeds different inert materials are used for coating the somatic embryoids like agrose and sodium alginate.

Advantages of Artifiial seeds

Artifiial seeds have many advantages over the true seeds

• Millions of artifiial seeds can be produced at any time at low cost.
• They provide an easy method to produce genetically engineered plants with desirable traits.
• It is easy to test the genotype of plants.
• They can potentially stored for long time under cryopreservation method.
• Artificial seeds produce identical plants
• The period of dormancy of artificial seeds is greatly reduced, hence growth is faster with a shortened life cycle.

Virus-free plants

The filed grown plants like perennial crops, usually are infected by variety of pathogens like fungi, bacteria, mycoplasma, viruses which cause considerable economic losses. Chemical methods can be used to control fungal and bacterial pathogens, but not viruses generally. Shoot meristem tip culture is the method to produce virus-free plants, because the shoot meristem tip is always free from viruses.

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Plant Regeneration Pathway

From the explants, plants can be regenerated by somatic embryogenesis or organogenesis.

Somatic Embryogenesis

Somatic embryogenesis is the formation of embryos from the callus tissue directly and these embryos are called Embryoids or from then in vitro cells directly form pre-embryonic cells which diffrentiate into embryoids.

Applications

• Somatic embryogenesis provides potential plantlets which after hardening period can establish into plants.
• Somatic embryoids can be be used for the production of synthetic seeds.
• Somatic embryogenesis is now reported in many plants such as Allium sativum, Hordeum vulgare, Oryza sativa, Zea mays and this possible in any plant.

Organogenesis

The morphological changes occur in the callus leading to the formation of shoot and roots is called organogenesis.

• Organogenesis can be induced in vitro by introducing plant growth regulators in the MS medium.
• Auxin and cytokinins induce shoot and root formation.

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Plant Tissue Culture Techniques and Types

Plant Tissue Culture (PTC)

Plant tissue culture is used to describe the in vitro and aseptic growth of any plant part on a tissue culture medium. This technology is based on three fundamental principles:

• The plant part or explant must be selected and isolated from the rest of plant body.
• The explant must be maintained in controlled physically (environmental) and chemically defined (nutrient medium) conditions.

Laboratory Facilities for PTC

For PTC, the laboratory must have the following facilities:

• Washing facility for glassware and ovens for drying glassware.
• Medium preparation room with autoclave, electronic balance and pH meter.
• Transfer area sterile room with laminar air-flw bench and a positive pressure ventilation unit called High Efficiency Particulate Air (HEPA) filter to maintain aseptic condition.
• Culture facility: Growing the explant inoculated into culture tubes at 22-28° C with illumination of light 2400 lux, with a photoperiod of 8-16 hours and a relative humidity of about 60%.

Technique Involved in PTC

1. Sterilization:

Sterilization is the technique employed to get rid of microbes such as bacteria and fungi in the culture medium, vessels and explants.

(i) Maintenance of Aseptic Environment:

During in vitro tissue culture maintenance of aseptic environmental condition should be followed, i.e., sterilization of glassware, forceps, scalpels, and all accessories in wet steam sterilization by autoclaving at 15 psi (121°C) for 15 to 30 minutes or dipping in 70% ethanol followed by flming and cooling.

(ii) Sterilization of culture room:

Floor and walls are washed fist with detergent and then with 2% sodium hypochlorite or 95% ethanol. The cabinet of laminar airflow is sterilized by clearing the work surface with 95% ethanol and then exposure of UV radiation for 15 minutes.

(iii) Sterilization of Nutrient Media:

Culture media are dispensed in glass containers, plugged with non-absorbent cotton or sealed with plastic closures and then sterilized using autoclave at 15 psi (121°C) for 15 to 30 minutes. The plant extracts, vitamins, amino acids and hormones are sterilized by passing through Millipore filter with 0.2 mm pore diameter and then added to sterilized culture medium inside Laminar Airflow Chamber under sterile condition.

(iv) Sterilization of Explants:

The plant materials to be used for tissue culture should be surface sterilized by fist exposing the material in running tap water and then treating it in surface sterilization agents like 0.1% mercuric chloride, 70% ethanol under aseptic condition inside the Laminar Air Flow Chamber.

2. Media Preparation

The success of tissue culture lies in the composition of the growth medium, plant growth regulators and culture conditions such as temperature, pH, light and humidity. No single medium is capable of maintaining optimum growth of all plant tissues. Suitable nutrient medium as per the principle of tissue culture is prepared and used.

MS nutrient medium (Murashige and Skoog 1962) is commonly used. It has carbon sources, with suitable vitamins and hormones. The media formulations available for plant tissue culture other than MS are B5 medium (Gamborg.et.al 1968), White medium (white 1943), Nitsch’s medium (Nitsch & Nitsch 1969). A medium may be solid or semisolid or liquid. For solidifiation, a gelling agent such as agar is added.

3. Culture condition

pH

The pH of medium is normally adjusted between 5.6 to 6.0 for the best result.

Temperature

The cultures should be incubated normally at constant temperature of 25°C ± 2°C for optimal growth.

Humidity and Light Intensity

The cultures require 50-60% relative humidity and 16 hours of photoperiod by the illumination of cool white florescent tubes of approximately 1000 lux.

Aeration

Aeration to the culture can be provided by shaking the flasks or tubes of liquid culture on automatic shaker or aeration of the medium by passing with fiter-sterilized air.

4. Induction of Callus

Explant of 1-2 cm sterile segment selected from leaf, stem, tuber or root is inoculated (transferring the explants to sterile glass tube containing nutrient medium) in the MS nutrient medium supplemented with auxins and incubated at 25°C ± 2°C in an alternate light and dark period of 12 hours to induce cell division and soon the upper surface of explant develops into callus. Callus is a mass of unorganized growth of plant cells or tissues in in vitro culture medium.

5. Embryogenesis

The callus cells undergoes differentiation and produces somatic embryos, known as Embryoids. The embryoids are sub-cultured to produce plantlets.

6. Hardening

The planets developed in vitro require a hardening period and so are transferred to greenhouse or hardening chamber and then to normal environmental conditions.

Hardening is the gradual exposure of in vitro developed plantlets in humid chambers in diffused light for acclimatization so as to enable them to grow under normal field conditions.

Types of Plant tissue cultures

Based on the type of explants other plant tissue culture types are:-

1. Organ culture
2. Meristem culture
3. Protoplast culture
4. Cell suspension culture.

1. Organ culture:
The culture of embryos, anthers, ovaries, roots, shoots or other organs of plants on culture media.

2. Meristem Culture:
The culture of any plant meristematic tissue on culture media.

3. Protoplast Culture:
Protoplasts are cells without a cell wall, but bound by a cell membrane or plasma membrane.Using protoplasts, it is possible to regenerate whole plants from single cells and also develop somatic hybrids. Th steps involved in protoplast culture.

(i) Isolation of protoplast:
Small bits of plant tissue like leaf tissue are used for isolation of protoplast. The leaf tissue is immersed in 0.5% Macrozyme and 2% Onozuka cellulase enzymes dissolved in 13% sorbitol or mannitol at pH 5.4. It is then incubated over-night at 25°C.

After a gentle teasing of cells, protoplasts are obtained, and these are then transferred to 20% sucrose solution to retain their viability. They are then centrifuged to get pure protoplasts as different from debris of cell walls.

(ii) Fusion of protoplast:
It is done through the use of a suitable fusogen. This is normally PEG (Polyethylene Glycol). The isolated protoplast are incubated in 25 to 30% concentration of PEG with Ca++ ions and the protoplast shows agglutination (the formation of clumps of cells) and fusion.

(iii) Culture of protoplast:
MS liquid medium is used with some modifiation in droplet, plating or micro-drop array techniques. Protoplast viability is tested with florescein diacetate before the culture. The cultures are incubated in continuous light 1000-2000 lux at 25°C. The cell wall formation occurs within 24-48 hours and the first division of new cells occurs between 2-7 days of culture.

(iv) Selection of somatic hybrid cells:
The fusion product of protoplasts without nucleus of different cells is called a cybrid. Following this nuclear fusion take place. This process is called somatic hybridization.

4. Cell Suspension Culture

The growing of cells including the culture of single cells or small aggregates of cells in vitro in liquid medium is known as cell suspension culture. The cell suspension is prepared by transferring a portion of callus to the liquid medium and agitated using rotary shaker instrument. The cells are separated from the callus tissue and used for cell suspension culture.

Production of Secondary Metabolites

Cell suspension culture can be useful for the production of secondary metabolites like alkaloids, flvonoids, terpenoids, phenolic compounds and recombinant proteins. Secondary metabolites are chemical compounds that are not required by the plant for normal growth and development but are produced in the plant as ‘byproducts’ of cell metabolism. For Example: Biosynthesis and isolation of indole alkaloids from Catharanthus roseus plant cell culture.

The process of production of secondary metabolites can be scaled up and automated using bio-reactors for commercial production. Many strategies such as biotransformation, elicitation and immobilization have been used to make cell suspension cultures more efficient in the production of secondary metabolites. Few examples of industrially important plant secondary metabolites are listed below in the table:

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Basic Concepts In Plant Disuse Culture

Growing plant protoplasts, cells, tissues or organs away from their natural or normal environment, under artificial condition, is known as Tissue Culture. It is also known as in vitro (In vitro is a Latin word, it means that – in glass or in test-tube) growth of plant protoplasts, cells, tissues and organs. A single explant can be multiplied into several thousand plants in a short duration and space under controlled conditions.

Tissue culture techniques are often used for commercial production of plants as well as for plant research. Plant tissue culture serves as an indispensable tool for regeneration of transgenic plants. Apart from this some of the main applications of Plant tissue culture are clonal propagation of elite varieties, conservation of endangered plants, production of virus-free plants, germplasm preservation, industrial production of secondary metabolites. etc., In this chapter let us discuss the history, techniques, types, applications of plant tissue culture and get awareness on ethical issues.

Gottlieb Haberlandt (1902) the German Botanist proposed the concept Totipotency and he was also the first person to culture plant cells in artifiial conditions using the mesophyll cells of Lamium purpureum in culture medium and obtained cell proliferation. He is regarded as the father of tissue culture.

Basic concepts of Tissue Culture

Basic concepts of plant tissue culture are totipotency, diffrentiation, dediffrentiation and rediffrentiation.

Totipotency

The property of live plant cells that they have the genetic potential when cultured in nutrient medium to give rise to a complete individual plant.

Differentiation

The process of biochemical and structural changes by which cells become specialized in form and function.

Rediffrentiation

The further diffrentiation of already differentiated cell into another type of cell. For example, when the component cells of callus have the ability to form a whole plant in a nutrient medium, the phenomenon is called redifferentiation.

Dediffrentiation

The phenomenon of the reversion of mature cells to the meristematic state leading to the formation of callus is called dediffrentiation. These two phenomena of rediffrentiation and dedifferentiation are the inherent capacities of living plant cells or tissue. This is described as totipotency.

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Applications Of Biotechnology

Biotechnology is one of the most important applied interdisciplinary sciences of the 21st century. It is the trusted area that enables us to find the benefiial way of life.

Biotechnology has wide applications in various sectors like agriculture, medicine, environment and commercial industries.

This science has an invaluable outcome like transgenic varieties of plants e.g. transgenic cotton (Bt-cotton), rice, tomato, tobacco, cauliflwer, potato and banana.

The development of transgenics as pesticide resistant, stress resistant and disease resistant varieties of agricultural crops is the immense outcome of biotechnology.

The synthesis of human insulin and blood protein in E.coli and utilized for insulin defiiency disorder in human is a breakthrough in biotech industries in medicine.

The synthesis of vaccines, enzymes, antibiotics, dairy products and beverages are the products of biotech industries. Biochip based biological computer is one of the successes of biotechnology.

Genetic engineering involves genetic manipulation, tissue culture involves aseptic cultivation of totipotent plant cell into plant clones under controlled atmospheric conditions.

Single cell protein from Spirulina is utilized in food industries. Production of secondary metabolites, biofertilizers, biopesticides and enzymes. Biomass energy, biofuel, Bioremediation, phytoremediation for environmental biotechnology.

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Transgenic Plants / Genetically Modified Crops

Herbicide Tolerant – Glyphosate

Weeds are a constant problem in crop filds. Weeds not only compete with crops for sunlight, water, nutrients and space but also acts as a carrier for insects and diseases. If leaf uncontrolled, weeds can reduce crop yields signifiantly.

Glyphosate herbicide produced by Monsanto, USA company under the trade name ‘Round up’ kills plants by blocking the 5-enopyruvate shikimate-3 phosphate synthase (EPSPS) enzyme, an enzyme involved in the biosynthesis of aromatic amino acids, vitamins and many secondary plant metabolites. There are several ways by which crops can be modified to be glyphosate-tolerant.

One strategy is to incorporate a soil bacterium gene that produces a glyphosate tolerant form of EPSPS. Another way is to incorporate a different soil bacterium gene that produces a glyphosate degrading enzyme.

Advantages of Herbicide Tolerant Crops

• Weed control improves higher crop yields;
• Reduces spray of herbicide;
• Reduces competition between crop plant and weed;
• Use of low toxicity compounds which do not remain active in the soil; and
• The ability to conserve soil structure and microbes.

Herbicide Tolerant – Basta

Trade name ‘Basta’ refers to a non-selective herbicide containing the chemical compound phosphinothricin. Basta herbicide tolerant gene PPT (L-phosphinothricin) was isolated from Medicago sativa plant. It inhibits the enzyme glutamine synthase which is involved in ammonia assimilation.

The PPT gene was introduced into tobacco and transgenic tobacco produced was resistant to PPT. Similar
enzyme was also isolated from Streptomyces hygroscopicus with bar gene encodes for PAT (Phosphinothricin acetyl transferase) and was introduced into crop plants like potato and sugar-beet and transgenic crops have been developed.

Insect resistance – Bt Crops:

(i) Bt Cotton

Bt cotton is a genetically modifid organism (GMO) or genetically modified pest resistant plant cotton variety, which produces an insecticide activity to bollworm. Strains of the bacterium Bacillus thuringiensis produce over 200 different Bt toxins, each harmful to different insects.

Most Bt toxins are insecticidal to the larvae of months and butterfles, beetles, cotton bollworms and gatfles but are harmless to other forms of life. The genes are encoded for toxic crystals in the Cry group of endotoxin. When insects attack and eat the cotton plant the Cry toxins are dissolved in the insect’s stomach.

The epithelial membranes of the gut block certain vital nutrients thereby suffient regulation of potassium ions are lost in the insects and results in the death of epithelial cells in the intestine membrane which leads to the death of the larvae.

Advantages

The advantages of Bt cotton are:

• Yield of cotton is increased due to effective control of bollworms.
• Reduction in insecticide use in the cultivation of Bt cotton
• Potential reduction in the cost of cultivation.
  

Disadvantages

Bt cotton has some limitations:

• Cost of Bt cotton seed is high.
• Effctiveness up to 120 days after that efficiency is reduced
• Ineffctive against sucking pests like jassids, aphids and whitefly.
• Affects pollinating insects and thus yield.

(ii) Bt Brinjal

The Bt brinjal is another transgenic plant created by inserting a crystal protein gene (Cry1Ac) from the soil bacterium Bacillus thuringiensis into the genome of various brinjal cultivars.

The insertion of the gene, along with other genetic elements such as promoters, terminators and an antibiotic resistance marker gene into the brinjal plant is accomplished using Agrobacterium – mediated genetic transformation. The Bt brinjal has been developed to give resistance against Lepidopberan insects, in particular the Brinjal Fruit and Shoot Borer (Leucinodes orbonalis).

(iii) Dhara Mustard Hybrid (DMH)

DMH – 11 is transgenic mustard developed by a team of scientists at the Centre for Genetic Manipulation of Crop Plants Delhi University under Government sponsored project. It is genetically modified variety of Herbicide Tolerant (HT) mustard.

It was created by using “barnase/barstar” technology for genetic modifiation by adding genes from soil bacterium that makes mustard, a self-pollinating plant. DMH – 11 contains three genes viz. Bar gene, Barnase and Barstar sourced from soil bacterium. The bar gene had made plant resistant to herbicide named Basta.

Virus Resistance

Many plants are affcted by virus attack resulting in series loss in yield and even death. Biotechnological intervention is used to introduce viral resistant genes into the host plant so that they can resist the attack by virus. This is by introducing genes that produce resistant enzymes which can deactivate viral DNA.

FlavrSavr Tomato

Agrobacterium mediated genetic engineering technique was followed to produce Flavr-Savr tomato, i.e., retaining the natural colour and flavour of tomato. Though genetic engineering, the ripening process of the tomato is slowed down and thus prevent it from softning and to increase the shelf life.

The tomato was made more resistant to rotting by Agrobacterium mediated gene transfer mechanism of introducing an antisense gene which interferes with the production of the enzyme polygalacturonase, which help in delaying the ripening process of tomato during long storage and transportation.

Golden rice – Biofortification

Golden rice is a variety of Oryza sativa (rice) produced through genetic engineering of biosynthesized beta-carotene, a precursor of Vitamin-A in the edible parts of rice developed by Ingo Potrykus and his group. The aim is to produce a fortifid food to be grown and consumed in areas with a shortage of dietary Vitamin-A.

Golden rice differs from its parental strain by the addition of three beta-carotene biosynthesis genes namely ‘psy’ (phytoene synthase) from daffdil plant Narcissus pseudonarcissus and ‘crt-1’ gene from the soil bacterium Erwinia auredorora and ‘lyc’ (lycopene cyclase) gene from wild-type rice endosperm.

The endosperm of normal rice, does not contain beta-carotene. Golden-rice has been genetically altered so that the endosperm now accumulates Beta-carotene. This has been done using Recombinant DNA technology. Golden rice can control childhood blindness – Xerophthalmia.

GM Food – Benefits

• High yield without pest
• 70% reduction of pesticide usage
• Reduce soil pollution problem
• Conserve microbial population in soil

Risks – believed to

• Affect liver, kidney function and cancer
• Hormonal imbalance and physical disorder
• Anaphylactic shock (sudden hypersensitive reaction) and allergies.
• Adverse effect in immune system because of bacterial protein.
• Loss of viability of seeds seen in terminator seed technology of GM crops.

Polyhydroxybutyrate (PHB)

Synthetic polymers are non-degradable and pollute the soil and when burnt add dioxin in the environment which cause cancer. So, efforts were taken to provide an alternative eco-friendly biopolymers. Polyhydroxyalkanoates (PHAs) and polyhydroxybutyrate (PHB) are group of degradable biopolymers which have several medical applications such as drug delivery, scaffld and heart valves.

PHAs are biological macromolecules and thermoplastics which are biodegradable and biocompatible. Several microorganisms have been utilized to produce diffrent types of PHAs including Gram-positive like Bacillus megaterium, Bacillussubtilis and Corynebacterium glutamicum, Gram-negative bacteria like group of Pseudomonas sp. and Alcaligenes eutrophus.

Polylactic acid (PLA)

Polylactic acid or polylactide (PLA) is a biodegradable and bioactive thermoplastic. It is an aliphatic polyester derived from renewable resources, such as corn starch, cassava root, chips or starch or sugarcane. For the production of PLA, two main monomers are used: lactic acid, and the cyclic diester, lactide. The most common route is the ringopening polymerization of lactide with metal catalysts like tin octoate in solution. The metalcatalyzed reaction results in equal amount of d and polylactic acid.

Green Fluorescent Protein (GFP)

The green florescent protein (GFP) is a protein containing 238 amino acid residues of 26.9 kDa that exhibits bright green florescence when exposed to blue to ultraviolet range (395 nm). GFP refers to the protein first isolated from the jellyfih Aequorea victoria.

GFP is an excellent tool in biology due to its ability to form internal chromophore without requiring any accessory cofactors, gene products, enzymes or substrates other than molecular oxygen. In cell and molecular biology, the GFP gene is frequently used as a reporter of expression. It has been used in modifid forms to make biosensors.

Biopharming

Biopharming also known as molecular pharming is the production and use of transgenic plants genetically engineered to produce pharmaceutical substances for use of human beings. Ths is also called “molecular farming or pharming”. These plants are different from medicinal plants which are naturally available. The use of plant systems as bioreactors is gaining more signifiance in modern biotechnology. Many pharmaceutical substances can be produced using transgenic plants. Example: Golden rice

Bioremediation

It is defined as the use of microorganisms or plants to manage environmental pollution. It is an approach used to treat wastes including wastewater, industrial waste and solid waste. Bioremediation process is applied to the removal of oil, petrochemical residues, pesticides or heavy metals from soil or ground water.

In many cases, bioremediation is less expensive and more sustainable than other physical and chemical methods of remediation. An eco-friendly approach and can deal with lower concentrations of contaminants more effectively. The strategies for bioremediation in soil and water can be as follows:

• Use of indigenous microbial population as indicator species for bioremediation process.
• Bioremediation with the addition of adapted or designed microbial inoculants.
• Use of plants for bioremediation – green technology.

Some examples of bioremediation technologies are:

• Phytoremediation – use of plants to bring about remediation of environmental pollutants.
• Mycoremediation – use of fungi to bring about remediation of environmental pollutants.
• Bioventing a process that increases the oxygen or air flow to accelerate the degradation of environmental pollutants.
• Bioleaching use of microorganisms in solution to recover metal pollutants from contaminated sites.
• Bioaugmentation a addition of selected microbes to speed up degradation process.
• Composting process by which the solid waste is composted by the use of microbes into manure which acts as a nutrient for plant growth.
• Rhizofitration uptake of metals or degradation of organic compounds by rhizosphere microorganisms.
• Rhizostimulation stimulation of plant growth by the rhizosphere by providing better growth condition or reduction in toxic materials.

Limitations

• Only biodegradable contaminants can be transformed using bioremediation processes.
• Bioremediation processes must be specifially made in accordance to the conditions at the contaminated site.
• Small-scale tests on a pilot scale must be performed before carrying out the procedure at the contaminated site.
• The use of genetic engineering technology to create genetically modifid microorganism or a consortium of microbes for bioremediation process has great potential.

Biofuel: Algal Biofuel

Algal fuel, also known as algal biofuel, or algal oil is an alternative to liquid fossil fuels, the petroleum products. This is also used as a source of energy-rich oils. Also, algal fuels are an alternative to commonly known biofuel sources obtained from corn and sugarcane. The energy crisis and the world food crisis have initiated interest in algal culture (farming algae) for making biodiesel and other biofuels on lands unsuitable for agriculture. Botryococcus braunii is normally used to produce algal biofuel.

Biological hydrogen production by algae

The biological hydrogen production with algae is a method of photo biological water splitting. In normal photosynthesis the alga, Chlamydomonas reinhardtii releases oxygen. When it is deprived of sulfur, it switches to the production of hydrogen during photosynthesis and the electrons are transported to ferrodoxins. [Fe]-hydrogenase enzymes combine them into the production of hydrogen gas.

Bioprospecting

Bioprospecting is the process of discovery and commercialization of new products obtained from biological resources. Bioprospecting may involve biopiracy, in which indigenous knowledge of nature, originating with indigenous people, is used by others for profit, without authorization or compensation to the indigenous people themselves.

Biopiracy

Biopiracy can be defined as the manipulation of intellectual property rights laws by corporations to gain exclusive control over national genetic resources, without giving adequate recognition or remuneration to the original possessors of those resources. Examples of biopiracy include recent patents granted by the U.S. Patent and Trademarks Office to American companies on turmeric, ‘neem’ and, most notably, ‘basmati’
rice. All three products are indigenous to the Indo-Pak subcontinent.

Biopiracy of Neem

The people of India used neem and its oil in many ways to controlling fungal and bacterial skin infections. Indian’s have shared the knowledge of the properties of the neem with the entire world.

Pirating this knowledge, the United States Department of Agriculture (USDA) and an American MNC (Multi Nation Corporation) W.R.Grace in the early 90’s sought a patent from the European Patent Office (EPO) on the “method for controlling of diseases on plants by the aid of extracted hydrophobic neem oil”. The patenting of the fungicidal and antibacterial properties of Neem was an example of biopiracy but the traditional knowledge of the Indians was protected in the end.

Biopiracy of Turmeric

The United States Patent and Trademark Office, in the year 1995 granted patent to the method of use of turmeric as an antiseptic agent. Turmeric has been used by the Indians as a home remedy for the quick healing of the wounds and also for purpose of healing rashes. The journal article published by the Indian Medical Association, in the year 1953 wherein this remedy was mentioned.

Therefore, in this way it was proved that the use of turmeric as an antiseptic is not new to the world and is not a new invention, but formed a part of the traditional knowledge of the Indians. The objection in this case US patent and trademark office was upheld and traditional knowledge of the Indians was protected. It is another example of Biopiracy.

Biopiracy of Basmati

On September 2, 1997, the U.S. Patent and Trademarks Offi granted Patent on “basmati rice lines and grains” to the Texas-based company RiceTec. This broad patent gives the company several rights, including exclusive use of the term ‘basmati’, as well proprietary rights on the seeds and grains from any crosses. The patent also covers the process of breeding RiceTec’s novel rice lines and the method to determine the cooking properties and starch content of the rice grains.

India had periled the United States to take the matter to the WTO as an infringement of the TRIPS agreement, which could have resulted in major embarrassment for the US. Hence voluntarily and due to few decisions take by the US patent office, Rice Tec had no choice but to lose most of the claims and most importantly the right to call the rice “Basmati”.

In the year 2002, the fial decision was taken. Rice Tec dropped down 15 claims, resulting in clearing the path of Indian Basmati rice exports to the foreign countries. The Patent Office ordered the patent name to be changed to ‘Rice lines 867’.