This document discusses the extraction, preparation, and storage of medicinal plants for experimental purposes. It outlines various extraction methods like maceration, infusion, digestion, and decoction. Medicinal plants can be prepared into liquid dosage forms like fluid extracts, infusions, tinctures, and syrups or solid forms like powders and granules. Storage is important to maintain the plant's properties, but extracts can be affected by biological, physical and chemical factors over time. Proper extraction methods and storage conditions are recommended to ensure quality and quantity of plant extracts for experiments.

1. The extraction, preparation and
storage of medicinal plants for
experimental purposes
Seminar presentation
By
Akem Lazare
1

2. Presentation outline
• Introduction
• Problem statement
• Rational
• Objectives
• Literature review
• Conclusion
• Recommendation
• References
2

3. Background
• A medicinal plant is any plant which in one or more of its
parts contains substances that can be used for therapeutic
purposes or for the synthesis of drugs.
• The use of herbal medicine for therapeutic purposes dates
back to the appearance of the human species.
• Medicinal plants serve as the richest bio-resource of drugs in
traditional medicine, modern medicine, nuetraceuticals, food
supplements, folk medicines, pharmaceutical intermediate
and chemical entities for synthetic drugs.
3

4. Background cont…
• WHO stated that about 25% of drugs prescribed worldwide
are derived from plants.
• For experimental purposes traditional plants has to be
extracted and processed properly this include;
- Timely collection, authentication, proper drying and
grinding followed by extraction using different solvents
- preparation of the extracts for experimental purposes
- storage of active principle
4

5. Problem statement
• Med plants usage over the past three decades,
•
• Med plants have impacted positively the healthcare system.
• Approxly 20% of plants have been use for pharmaceutical
purposes to treat deadly/ harmful diseases.
• Despite this they has been some recorded adverse effect or
ineffectiveness of some med plants this has been attributed to;
 poor quality of plant source, inappropriate manufacturing and
processing of medicinal plants.
 including the correct storage of plant source species and the
selection of appropriate parts
5

6. Rational
• Preparation of medicinal plants for experimental purposes is
the first step and key in achieving quality research outcome
• Among the various steps, the extraction and storage of med
plants extracts are very important as they maintain the
products physical and chemical properties closer to those
found in the fresh plant, and failures may influence the
quality of the final product.
• most study on the preparation of medical plants for
experimental purposes focuses on the extraction,
fractionalization, isolation, identification of bioactive
compounds forgetting the storage
6

7. Objectives
Main objectives
• To review the importance and various methods involve in the
extraction and storage of medicinal plants and the types of
medicinal plant preparations commonly use for experimental
purposes
Specific objectives
• To discuss the importance and various methods of medical
plant extraction
• To review the types of medicinal plants preparations
• To bring out the importance and methods of storing medical
plants 7

8. Literature review
• Medicinal plant refers to a plant comprising active
ingredients or secondary metabolites that possess biological
activity.
• There are testimonies from 5,000 years BC written on
Sumerian clay plate in Nippur, within the Old Testament
• Uses in folk and modern medicines
• They're not disease specific
• They're self-contained and nutritive in nature
8

9. Literature review cont…
• Types of bioactive products from med plants
• Bioactive cpds are secondary metabolites having pharmacological
or toxicological effects in man or animals. Such as anti-
inflammatory,
• They can be either
• - Non starchy polysaccharides e.g cellulose with water holding
capacity
• - antibacterial and antifungal e.g terpenoids, alkaloids which inhibit
microbial growth
• - antioxidants e.g flavoids carotenoids with 02 free radical
quenching ability
• - anticancer e.g polyphenols which inhibit tumor growth
9

10. Literature review cont…
Extraction of med plants
• Is the separation of medicinally active portions of plants from
inactive or inert components using selective solvents and
SEPs
• It can be influenced by heat stability, nature of solvent, cost
of the drug, period of extraction, final volume required,
intended use.
• Solvents of extraction/menstrum use depends on the type of
plant, part of the plant, nature of the bioactive cpds and
availability of solvents
10

11. Literature review cont…
Extraction of med plants cont..
• Properties of solvent extractions
Water: most polar and for wide range polar cpds, it is cheap,
nontoxic, non-inflammable but promotes microbial growth, hydrolysis
and high amt of heat is needed to concentrate the extract.
Alcohols: miscible with water it is self preservative nontoxic in low
concentration, less amt of heat to concentrate but it does not dissolve
fats, gums and it is flammable.
Chloroform: nonpolar use to extract cpds such as terpenoids,
flavonoids etc. it is colorless, sweet smell and soluble in alc but
sedative and carcinogenic
Ether nonpolar use to extract alkaloids, terpenoid, coumarins
Ionic liquid: highly polar, heat stable, it attract and transmit
microwave non flammable and useful for liquid-liquid extraction
But is not ideal for tinctures preparation
11

12. Literature review cont…
Factors to be considered in selecting solvents of
extraction
- Selectivity
- Safety
- Cost
- Reactivity
- Recovery
- Viscosity
- Boiling temperature
12

13. Literature review cont…
Methods of extraction
 Maceration
 Infusion
 Digestion
 Decoction
 Percolation
 Soxhlet extraction
 Microwave-assisted extraction
 Ultrasound-assisted extraction
13

14. Literature review cont…
Medicinal plants can be prepared into the following forms:
• Preparation of liquid herbal dosage forms
Preparation of fluid extracts:
Preparation of decoctions:
Preparation of infusions
Preparation of tinctures
Preparation of syrups
Preparation of aromatic waters
Preparation of plant powders
Preparation of granules
14

15. Literature review cont….
• Storage of medicinal plants during experimentation
• Purpose of Storing Medicinal Plants
• Freezing specimens
• The temperature of the storage
• Stored in a specially designed metal herbarium cabinet
• Folders should be removed from cabinets only as necessary
• Original field notebooks or copies must be permanently
retained
15

16. CONCLUSION
• Methods use in the extraction of plants extracts are;
• Maceration which is a convenient method and very suitable for
thermolabile plant material.
• Infusion which is suitable for extraction bioactive constituents
that is readily soluble,
• Digestion suitable for plant materials that are readily soluble,
• Decoction suitable for extraction of water soluble and heat
stable plant material,
• Percolation which uses a percolator 16

17. Conclusion cont…
• Medicinal plants can be prepared into different dosage form for
experimental purposes this includes;
• liquid dosage form which are referred to as oral preparations
• Types of liquid preparation include;
• Fluid extracts which are prepared by
 percolation of herbal material(s) using an aqueous alcoholic
menstruum,
 Infusions prepared by macerating the herbal materials for a short
period of time with warm or boiling water,
 Tinctures prepared by either maceration or percolation, using
ethanol, wine
 Syrups are usually prepared by adding sucrose (at least 45% m/m)
• solid preparation like;
 Powders that are prepared by grinding or pulverizing dried herbal
materials to a suitable particle size,
 granules, where the dried liquid extract is blended with diluents,
binders or other suitable excipients, then wetted with an
appropriate binding solution or solvent to promote agglomeration.
17

18. Conclusion cont….
• Based on the storage of medicinal plants extract, it has been
showed that can be affected both by
• biological factors like; microorganism, insects and rodents and
•
• physical factors such as sunlight.
• Chemical interaction is another factor as well as the period of
storage
18

19. RECOMMENDATION
• To ensure the quality and quantity of medicinal plants
extract to be used for experimental purposes,
• the appropriate method of extraction should be used
together with the solvent of choice depending on the nature
of the molecule to be obtain.
19