Biotechnology: Class 11 — Chapter 1: Introduction

Ancient biotechnology dates back to the Paleolithic era (around 10,000 years ago) with early agricultural practices, animal domestication, and traditional food preservation techniques.

• Selective Breeding: Early humans collected seeds of wild plants for cultivation and domesticated wild animals, performing primitive genetic selection.
• Traditional Fermentation: Production of bread, cheese, wine, beer, and vinegar without modern microbiological knowledge.
• Indian Traditional Foods: Preparation of fermented items such as dahi (curd), idli, kinema, and local beverages using indigenous biological resources.

Curd Making (Traditional Biotechnology):

Fresh Milk (boiled to 100°C and cooled to 37°C) + Inoculum (one-day-old curd containing Lactobacillus) → Coagulated Curd (after 4-5 hours of incubation).

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Biochemical Mechanism: Lactobacillus bacteria convert lactose sugar into lactic acid. The resulting acidity denatures the globular milk protein casein, causing it to coagulate into solid curd while separating the liquid whey protein layer.

The chemical equation representing classic yeast fermentation of sugars into ethanol is:

The foundation of modern biotechnology was built upon key scientific discoveries during the 16th to 20th centuries:

Modern biotechnology is driven by rDNA technology, which allows scientists to cut, join, and transfer genes from one organism to another to confer novel properties with high precision.

1. Identification of the protein of interest.
2. Isolation of the gene coding for the target protein from the donor genome.
3. Inserting the gene into a suitable cloning vector (e.g., plasmid).
4. Introduction of the modified vector into a compatible host cell (transformation).
5. Multiplication of the host cell containing the recombinant vector.
6. Expression and scale-up of the desired protein product.

• Therapeutic Proteins: Production of biopharmaceuticals in heterologous systems. E.g., recombinant human insulin (humulin) produced in Escherichia coli and Saccharomyces cerevisiae; human growth hormone; and blood anti-coagulants expressed in the milk of transgenic goats.
• Gene Therapy: Delivery of functional genes into a patient's cells to replace defective genes. First clinical trial attempted by Martin Cline (1980) for β-thalassemia. First successful clinical trial performed in 1990 on Ashanthi De Silva for Adenosine Deaminase deficiency (ADA-SCID). Commercial products include Gendicine (approved in China, 2003 for cancer) and Neovasculgen (approved in Russia, 2011 for peripheral artery disease).
• Genetic Testing: Diagnostic assays to identify chromosomal defects, gene mutations, and protein expression anomalies (e.g., tests for phenylketonuria and congenital hypothyroidism).

• Bt Cotton: Transgenic crop expressing the insecticidal crystal protein Cry 1A(b) derived from the soil bacterium Bacillus thuringiensis, conferring resistance against bollworms.
• Virus Resistance: Transgenic plants expressing viral coat protein genes to prevent viral replication (e.g., resistance against Papaya Ring Spot Virus and Cucumber Mosaic Virus).
• Abiotic Stress Tolerance: Tobacco plants engineered with glycerol-1-phosphate acyl-transferase from Arabidopsis for chilling tolerance; Roundup-ready soybeans engineered for tolerance to the herbicide glyphosate.
• Nutritional & Quality Enhancement: Flavr Savr tomato engineered for delayed ripening and extended shelf life; Golden Rice engineered with beta-carotene biosynthetic pathways to combat Vitamin A deficiency.
• Plant Tissue Culture: Micropropagation of elite clones, haploid production via anther/pollen culture, and germplasm conservation.
• Edible Vaccines: Transgenic plants (e.g., potatoes) expressing antigenic proteins from pathogens to induce immunity upon consumption (e.g., vaccines against measles and cholera).
• Biofuels: Generation of renewable energy from biomass. Includes bioethanol, bio-butanol, biodiesel (from Jatropha curcas, rapeseed, animal fats), bio-ethers, and biogas.

• Food Processing: Improving texture, nutritional value, and shelf life of foods; large-scale production of fermented foods (cheese, yoghurt, probiotics) using engineered enzymes.
• Environmental Biotechnology: Application of biological systems to monitor and remediate polluted environments.
• Eco-toxicological Biomarkers: Biological indicators used to detect environmental pollutants. E.g., the lux reporter gene expressed in E. coli acts as a bioluminescent sensor for mercury contamination.
• Bioremediation: Using micro-organisms to degrade hazardous pollutants. E.g., biphenyl dioxygenase gene engineered into E. coli to degrade polychlorinated biphenyls (PCBs).
• Phyto-remediation: Using hyper-accumulator plants to extract and sequester heavy metals (Cadmium, Mercury, Lead) from contaminated soils. E.g., Brassica napus and Helianthus annuus.

The Government of India established the National Biotechnology Board (NBTB) in 1982, which was upgraded to the Department of Biotechnology (DBT) in 1986 under the Ministry of Science and Technology.

The Indian biotechnology sector is divided into five major segments: Bio-pharma, Bio-services, Bio-agri, Bio-industrial, and Bio-informatics. India ranks among the top 12 biotechnology destinations globally and is the 3rd largest in the Asia-Pacific region.

• Vaccines: India is the world's largest producer of recombinant Hepatitis B, measles, and DTP vaccines. Key achievements include ROTAVAC® (first indigenous rotavirus vaccine by Bharat Biotech) and Covaxin (first indigenous Covid-19 vaccine).
• Therapeutics: India is the largest global producer of Statins and Immunosuppressants. Developed INSUPEN, a reusable insulin delivery device.
• Agriculture: Bt cotton accounts for 45% of the Indian hybrid seed market. Developed Samba Mahsuri (blight-resistant rice via marker-assisted selection), flood/drought-tolerant rice, and high-protein GM maize.