I prepared this presentation in 2015 for the Food Biotechnology Course (GEB-504) during my Masters.

1. Development of New Biotech Food Products:
Fruits
Presented by
Nafisa Nawal Islam
Class: M.S., Roll No.: 14, Session: 2014-15
Dept. of Genetic Engineering and Biotechnology
University of Dhaka
Course No.: 504

2. - employs the tools of modern genetics
to achieve/ enhance desired traits of plants, animals &
microorganisms for food production
by adding / extracting selected genes
- benefit environment, society & consumer health.
Food Biotechnology
Nafisa Nawal Islam

3. • Fruits with vaccines
• Transgenic bananas
- constitutively expressing the hypersensitive response-
assisting protein (Hrap) or plant ferredoxin-like protein
(Pflp) gene from sweet pepper
- to combat Banana Xanthomonas wilt
caused by Xanthomonas campestris pv. musacearum.
• Melons, strawberries, kiwi, pineapple, mango, other fruits
Biotechnology is needed because nature does not
contain all the genetic variation men desire
Nafisa Nawal Islam

4. Genetically engineered fruits
Papaya Resist papaya ringspot virus (PRSV) by over-expression of
the viral coat protein
Squash Resist watermelon mosaic 2, zucchini yellow mosaic,
cucumber mosaic viruses
Tomato - Altered ripening to enhance fresh market value
- Thicker skin & altered pectin to enhance processing value
Sugarbeet Resist glyphosate (herbicide)
Non-
browning
apple
- does not go brown after fresh cut;
- retains all its natural flavor & taste
RSV
resistant papaya
Susceptible
plants
Nafisa Nawal Islam

5. Trait/Gene Examples
Trait Gene
Insect Resistance Bt-toxin protein
Glyphosate resistance Bacterial EPSP synthase enzyme
Plant Virus Resistance Viral Coat Protein
Plant Bacterial Resistance P35
Male Sterility Barnase
Salt tolerance Glyoxylase I, AtNHX1
Cold Tolerance CBF transcription factors
Increased Vitamin-A content Vitamin A biosynthetic pathway enzymes
Mercury Resistance Mercuric ion reductase

6. Modern Plant Biotechnology & Transgenic
Plant technologies are reliant on Tissue Culture
• Propagating plants “in vitro”
• Tissue culture is required to generate transgenic
plants
Reasons to use tissue culture:
• Virus free reproduction
– Bananas
• Make many identical clones
Nafisa Nawal Islam

7. Plant Biotechnology Techniques Fall Into 2 Classes
• Identify a gene from another species which controls a trait of interest
• Or, modify an existing gene (create a new allele)
1) Gene Manipulation
Gene of Interest
IS IS
T-DNA
Border
T-DNA
Border
Selectable
Marker
• Transferring gene into an organism to develop transgenic organisms
• Technique called transformation
2) Gene Introduction
Nafisa Nawal Islam

8. Field test the plants
- Multiple sites
multiple years
Culture plant
tissue
- Develop shoots
- Root the shoots
Introduce Gene
to the target
Plant
- Agrobacterium
- Gene gun
Prepare tissue
for
transformation
Transformation Steps
Nafisa Nawal Islam

9. Field Testing
Non-transgenicsTransgenics
Herbicide Resistance
Final Test
Consumer Acceptance
RoundUp Ready Corn
Before After
Lab Testing
The Transgenics
Regenerate Transgenic Plants
on Selection Medium
Nafisa Nawal Islam

10. * Induced Mutation Assisted Breeding (IMAB)
 Many plant varieties were subjected to mutagenic agents (like
radiation) to induce mutations & then selected for the desired “new”
traits that appeared.
 IMAB has resulted in the introduction of new varieties of apples,
citrus fruits, sugar cane & banana.
* Micro-propagation
 involves taking small sections of plant tissue, or entire structures such
as buds, & culturing them under artificial conditions to regenerate
complete plants.
 In Kenya, banana shoot tips have been successfully tissue-cultured to
regenerate disease-free banana plantlets from healthy tissue.
Nafisa Nawal Islam

11. Food Biotechnology Applications
1. High yield / agricultural productivity
2. Insect-resistant plants
- Bt toxin, Cowpea trypsin inhibitor etc.
3. Disease-resistant plant
4. Herbicide-resistant plant
Genetic Modificaton of fruit crops include
- Gene transformation: Apple, Cherry, Papaya
- Somaclonal variation: Orange
5. Edible vaccines
6. Improve value of feed crops
- Transfer a fungal enzyme (phytase) to crops to remove phytic acid
from feed & improve phosphate availability
7. Development of tools for breeding for
- improved food processing & fruit quality (texture, taste, storage ability)
- phytopathogen resistance (both in the field & post-harvest)

12. 7) Virus-resistant plants
Figure: Procedure for putting CuMV
Coat protein into plants
• Overexpression of the virus coat
protein, e.g.
- cucumber mosaic virus (CuMV) in
cucumber
- PRSV in papaya
- tobacco mosaic virus in tomato.
• Expression of antiviral proteins
(pokeweed)
Nafisa Nawal Islam

13. 8) Fungus- & bacterium-resistant plants
Addition of two bacterial genes in plants
Overproduction of salicylic acid
Over-expression of NPR1 gene
- encodes the master regulatory protein
for
pathogenesis-related (PR) protein
Production of PR proteins
(b1,3-glucanases, chitinases, thaumatin-
like proteins, & protease inhibitors)
Nafisa Nawal Islam

14. • Over-expression of the
gene encoding a Na+/H+
antiport protein in
vacuole membrane
which transports Na+
into the plant cell
vacuole
• Done in tomato
allowing them to
survive on 200 mM salt
(NaCl)
• If transporters known,
engineer plants to
phyto-remediate toxic
soils Figure: Schematic representation of ion transport in the
plant A. thaliana showing the Na+ ions being
sequestered in the large vacuole
Control
tomatoes at 200
mM NaCl
Transformed tomatoes
at 200 mM NaCl
Tolerance to Aluminium (a growth limiting factor in acid soils;
is in the early phase of R&D for several crops, including papaya.)
9) Development of stress (i.e. salt)-tolerant plants
Nafisa Nawal Islam

15. 10) Development of senescence-tolerant plants:
Flavorful Tomatoes
• Fruit ripening is a natural aging process that involves 2
independent pathways: flavor development & fruit softening.
• Tomatoes are picked when not very ripe (hard & green) to
allow for safe fruit-shipping, shipped to market & treated
with ethylene before sale at wholesale level
• Flavr Savr tomato blocked polygalactonurase (a plant
enzyme that degrades plant cell wall pectins & contributes to
fruit softening) synthesis by antisense.
Flavor development pathway
Fruit softening pathway
Green Red
Hard Soft
polygalacturonase
antisense polygalacturonase
• Future Prospective: Could be used on any climacteric fruits
Nafisa Nawal Islam

16. 11) Modification of plant nutritional content
• Use metabolic engineering
to insert new pathways into plants or
improve expression of enzymes in existing ones
• Amino acids (corn is deficient in lysine, methionine &
tryptophan; legumes are deficient in methionine &
cysteine)
• Lipids (altering the chain length and degree of
unsaturation is now possible since the genes for such
enzymes are known)
• Low fat content
• Increased levels of antioxidants
- vitamin C, phenolics, etc.
• Improving vitamin content of plants
- Vitamin E (a-tocopherol) & vitamin A
Nafisa Nawal Islam

17. 11) Modification of plant nutritional content:
Increasing the vitamin E (a-tocopherol) content
• Plants make g-tocopherol but
very little a-tocopherol;
they do not produce enough
methyltransferase (MT)
• The Arabidopsis MT gene was cloned,
expressed under the control of a seed-specific carrot promoter,
and found to produce 80 times more vitamin-E in the seeds.
• Similarly, GE ‘super banana’ can be produced.
Nafisa Nawal Islam

18. Strawberry Production in Bangladesh
• 3 varieties (RB-1, RB-2 & RB-3)
have been innovated & found
adaptive to the region’s soil &
environmental conditions.
• 2 out of the 3 were found very
impressive in size, taste & flavor.
Future prospects: Sweetness increase
Nafisa Nawal Islam

19. Development of cost-effective high throughput sequencing technologies
Significant increase in availability of genomic information for fruit species
Improved understanding of many important crop traits (timing
of flowering, control of juvenility, ripening, shelf life etc.)
Recently developed genome-editing tools for fruit improvement
Novel biotechnological tools:
• Zinc finger nucleases (ZFNs)
• Transcription activator-like effector nucleases (TALENs)
• Clustered regulatory interspaced short palindromic repeat
(CRISPR)
- the latest development in the genome-editing toolbox
- based on bacterial form of adaptive immune system
- simple, most efficient, cheap, easy to design & user-friendly
Nafisa Nawal Islam

20. Opportunities:
• The advent of new genome-editing tools makes it possible to
manipulate the plant genome with unprecedented control.
• Engineered nucleases (i.e., ZFNs & TALENs) generate dsDNA breaks at
almost any specific genomic location, allowing precise genome
editing.
Absence of foreign
DNA, notably
selectable markers
in the final product
Introduction of genes
derived from same
plant species through
site-specific insertion,
deletion, mutation
Development of novel,
consumer-acceptable GM
products developed with
these technologies
Recently developed genome-editing tools for fruit improvement
Nafisa Nawal Islam

21. Concluding Remarks & Future Perspectives
• Fruit crops with superior phenotypes developed with the recent
genome-editing tools
- might be considered as non-transgenic genetically altered plants.
- can be commercializeded even in countries where GM crops are
poorly accepted.
Food biotechnology has the potential to:
• Reduce levels of natural toxins in plants
• Provide simpler & faster ways to locate pathogens, toxins &
contaminants
• Keep products fresher longer
• Identify ways to eliminate allergens from foods
• Ensure food security
Nafisa Nawal Islam

22. Thank You
Nafisa Nawal Islam