This document discusses metabolomics, which is the study of metabolites in organisms. It describes key terms like metabolome and different omics approaches. Metabolomics deals with identifying and quantifying small molecules like peptides, amino acids, and organic acids. It is important for understanding genetic improvement and crop performance under stress. Different extraction and analytical techniques are used like LC-MS and NMR. Case studies show how metabolomics identified compounds related to thrips resistance in chili and changes in flavonoids, polyamines and alkaloids during pollen development in tomatoes under heat stress. Limitations and prospects of metabolomics in discovering biomarkers and beneficial compounds are also covered.

1. G. Sandeep
2019634006
Ph.D Vegetable Science
TNAU, Coimbatore

2. • Omics – collective characterization and
quantification of cumulative biological molecules
that gets translated into –
– Structure
– Function
– Dynamics of an organism
– Suffix “OME” – used to address the object of study
such as
– Genome
– Proteome
– Metabolome
“OMICS”

3. • Branch of science - “OMICS” – represented
with suffix
• It represents various disciplines in biology
– Genomics
– Transcriptomics
– Epigenomics
– Proteomics
– Metabolomics
– Phenomics
– Glycomics

4. OMICS APPROACH
• Information – enhanced the precision and
speed of breeding programs
• For developing Climate smart , Nutrition rich
germplasms – ensures “Food Security”
• Other omics approach like phenomics has
evident outcomes in crop improvement and
performance
• Genomics – achieving higher genetic gain

5. METABOLOMICS
• Scientific study of chemical processes involving
metabolites
– Small Molecule substrate
– Intermediates
– Produdcts of metabolism
• It is a "systematic study of the unique chemical
fingerprints that specific cellular processes leave behind",
the study of their small-molecule metabolite profiles
• Metabolomics – complex than other omics approaches
• Inadequate attention in crop science
– Trait mapping
– Plant selection

6. • Deals with identification and quantification of
metabolites in a plant system.
• Molecular weight – usually <1500 Da – Occasionally
30 – 3000 Da
• These small group of molecules are called
“METABOLOME”
• Molecules includes variety of metabolites such as
peptides, amino acids, nucleic acids, carbohydrates,
organic acids, vitamins, flavonoids, polyphenols,
alkaloids, minerals or any other chemical compound
that is used, metabolized or synthesized by a cell or by
a given organism
(Turner et al.,2016)

7. Significance of Metabolomics
• Metabolomics – very important - genomic study and
results could be the basis of genetic improvement
• Based on the crop studies their chemical composition
(nutritional and functional aspects) – their participation
in the resistance against pest species, stress etc can be
studied.
• Metabolomics is a crucial technology to study
– Abiotic stress tolerance
– Pathogen resistance
– Robust ecotypes
– Metabolomic Assisted breeding

8. • In Plant kingdom ~200,000 compounds are
still unknown.
• Around 10,000 secondary metabolites
discovered from different plant sp.
• Modern metabolomics platforms – explain
complex biological pathway
• To explore hidden regulatory networks
controlling growth and development

9. Extraction Methods in metabolomics
• There are numerous extraction methods to extract and isolate compound of
interest
• In extraction it is important that methods of extraction should be
– Simple
– Robust
– Less time
– Repeatable
– Cheap
• Solvent used should dissolve diverse metabolites
– Aqueous methanol
– Ethanol
– Perchloric acid
– Acetonitrile
– Water
are commonly used as extraction solvents

11. Analytical technique
• Analytical technique – reliable data –
behaviour/ response of plant species – diverse
environmental factors
• Various instruments used to get analytical
results
– High‐performance liquid chromatography (HPLC)
– Gas chromatography (GC) coupled with mass
spectrometry (MS)

12. • To analyse the complex
metabolites – require high
resolution, precise and
sensitive sensors
• Based on these limitations
in instruments – advanced
analytical technologies
can be used
• Nuclear magnetic
resonance (NMR)
• GC and HPLC coupled
with MS
• Capillary electrophoresis
coupled with MS

13. Schematic representation
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5545584/

15. CROP IMPROVEMENT USING
METABOLOMICS
CASE STUDIES

17. • AIM & OBJECTIVE
– To find resistance against thrips
(Frankliniella occidentalis) in
chilli due to untargeted metabolite
– To find the metabolite that
provides defense against the thrips
MATERIALS & METHODS
– 11 Capsicum accessions
– C. annuum and C. chinense
– Liquid chromatography (LC)
coupled with mass spectrometry
(MS) (LC-MS)
VEGETATIVE STAGE
FLOWERING STAGE

19. Result and conclusion
• In the presence of
Monomer & Dimer DTG
related to Thrips resistance
(63)
• Sucrose, flavone
glycosides and
chlorogenic acid were
related to thrips
susceptibility (52 & 43)
• Increasing the levels of
DTG in elite breeding
lines could be a way to
increase insect resistance
in pepper crops
https://link.springer.com/article/10.1007/s10886-019-01074-4

20. • AIM & OBJECTIVE
– To study pollen development metabolomics
– Response of pollen and its metabolite during heat stress
– To study the untargeted metabolomic analysis of developing pollen
under a changing environment
• Materials & Methods
– Tomato – Cultivar MICRO TOM (JAPAN)
– To detect secondary metabolites - pollen of tomato (Solanum
lycopersicum L.) - three developmental stages - control conditions and
after a short heat stress at 38 C.
– Liquid chromatography–mass spectrometry

21. • Three pollen
developmental stages -
A. Polarized Microspore
B. Early Bi-cellular Pollen
C. Mature Pollen
• Identified secondary
Metabolites (3 groups)
– Flavonoids
– Polyamines
– Alkaloids
C: CONTROL ; HS: HEAT STRESS

22. • Young pollen stages accumulated specific conjugated polyamines and alkaloids, whereas mature pollen
stage accumulated more flavonoids.
– During pollen development, the total abundance of flavonoids increased significantly by 8.5-fold from
polarized microspore (6mm) to mature pollen stage
• The short heat stress of 2 h at 38 C led to an increase in total content of flavonoids upon stress in the
microspore stage (6 mm)
• The accumulation of flavonoids may protect against oxidative damage induced by the temperature
increase and resulted in tolerance against heat stress.
Result and Conclusion

23. Limitations
• Very complex to find wide range of metabolites
• The metabolome is sensitive to various genetic and
environmental stimuli, so metabolomic study requires the
consideration of a number of factors.
• Most of the metabolites - part of multiple pathways –
difficult to analyze
• Interpretation of data from many metabolites provide
huge results and its difficult with normal statistical tool

24. Prospects of Metabolomics
• Relevant in the discovery of
“BIOMARKERS”
• Helps to explore more about cell function
in depth
• Beneficial effects of the compounds can
be made available to the general public
• Helps to rewire the natural metabolic
process
• Metabolomic- Assisted Breeding helps to
produce new varieties with beneficial
phytochemicals/ bio fortified varieties

25. THANK YOU