Work Package 3:
Phytochemical characterisation of
active materials
Lead partner: NRI-UOG
Involved partners: RBGKEW, MUM, UZ
Justification
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Use of plants as pesticides established &
effective for crop, storage protection, livestock
treatment.
So why the need for chemistry?
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Requires expensive equipment
Time consuming
Justification - scientific
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Pesticidal plant use improved via understanding the
chemistry that governs activity e.g.,

enhancing application methods
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improving harvesting strategies - less long term damage
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correct time of year
correct part of plant
identifying alternatives species for scarce or threatened ones
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water soluble components applied as water extracts reducing
amounts needed
some plants are effective & popular but over-harvested
abundant plants with similar chemistry environmentally benign
alternative
Authentication & validation
Identification of toxins
Justification - institutional

The ability of SADC partners to carry out this analytical work is
presently limited

capacity needs to be built.

This WP will incorporate significant training component
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analytical and preparative techniques
bioassays techniques
Objectives WP3

Chemical profiling of at least 10
pesticidal plants - selection based
on information arising from WP2
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through literature surveys.
from published indigenous use in pest
control.
information obtained from farmers
plants that farmers demonstrate to be
effective
Plants used in other places but not in
our region.
Objectives WP3

Identification of key bioactive components
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Use literature & chemical database compound searches
Chemical analysis using LC-MS / GC-MS / NMR
Compound purification
Biological activity testing of processed materials, extracts & pure
compounds to verify activity
Optimise approaches to harvesting e.g., Securidaca
longepedunculata


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Roots vs. bark
Water extract vs. powdered root/bark.
Ensure correct ID of species Cissus populnea vs. Cassia sophera
Objectives WP3

Capacity building through staff exchange & training of
SADC scientists (Mzuzu University & University of
Zimbabwe)

in UK labs at NRI-UOG and RBG-Kew
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through formal training – PhD?

to develop appropriate analytical techniques for technology
available in SADC.
Outputs
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At least 3 peer reviewed papers.

Training document for rapid and straightforward
chemical analysis of plant materials
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Specifically plants for which info is collected within the project.
More general techniques specific to biological activity testing
Provision of standard texts e.g., Phytochemical methods
Methods to be relevant.
Where & How?
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RBG-Kew NRI-UOG can provide
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analytical chemistry GC-MS, LC-MS, NMR
compounds isolation
biological activity testing

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Stored product pests e.g., Callosobruchus & Sitophilus spp.
Field crop pests e.g., Bemisia & Spodoptera spp.
Invertebrate & unicellular parasites?
Needs to be prioritised – what are the most important and relevant
tests
Mzuzu University & University of Zimbabwe
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Analytical plant chemistry – HPLC.
Biological activity testing
Capacity building and training
Questions for discussion

Training – who & how?
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Who works on which plants?
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Divided up by plants species or use?
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Material Transfer – access to plants.
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Biological activity testing.
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Who runs which bioassays?
Which organisms?
Where to get livestock parasite bioassays done