The document provides an overview of bioactive compounds, including their history, classification, and the methods for extraction. It details conventional extraction techniques such as Soxhlet extraction, maceration, and hydro-distillation, along with non-conventional techniques like supercritical fluid extraction and microwave-assisted extraction. Additionally, it emphasizes the significance of bioactive compounds in health and their physiological effects, alongside providing insights into their synthesis pathways.

1. Understanding Bioactive Compounds:
Basics of Extraction and Standard Curve Construction
Md Shahjahan Kabir
B.Sc. In Food and Process Engineering
MS in Food Processing and Preservation (1st semester)
Hajee Mohammad Danesh Science and Technology university, Dinajpur

2. History and definition of
bioactive compounds
01 Extraction of bioactive
compounds
02
Classification and synthesis
of bioactive compounds
03 Conventional extraction
techniques
04
Non-conventional extraction
techniques
05
WHAT WE WILL LEARN

3. History and definition
of bioactive compounds

4. • Plants have served mankind since the dawn of humanity, transitioning from basic nutrition to
valuable sources of medicine and health improvement.
• Egyptian papyruses indicate coriander and castor oil's diverse applications in medicine,
cosmetics, and preservation across numerous recipes. During the Greek and Roman periods,
scholars like Hippocrates and Dioscorides described thousands of therapeutic uses for herbal
plants. Romanians have a long history of utilizing medicinal herbs, with references dating back to
Herodotus in the 5th century B.C.
• This historical use illustrates the rich tradition of bioactive molecules in ancient remedies,
predating our modern understanding of their mechanism.

5. • Bioactive compounds are naturally occurring chemicals
found in plants, animals, fungi, and microorganisms that
have biological activity and can have a beneficial effect on
human health when consumed.
• These compounds often exhibit specific physiological
effects in the body, such as antioxidant, anti-inflammatory,
antimicrobial, or anticancer properties.

6. • Bioactive compounds in plants, typically produced as
secondary metabolites, aid in survival and interaction with
the environment. Primary metabolites support growth,
while secondary metabolites enhance resilience against
local challenges.
• Bioactive compounds in plants is secondary plant
metabolites eliciting pharmacological or toxicological
effects in human and animals.

7. Classification and synthesis of
bioactive compounds

8. Classification of bioactive compounds
• Classification of bioactive compounds in different categories is still
inconsistent rather it depends upon the intention of the particular
classification.
• example, biosynthetic classifications which serve the simplicity of the
description of biosynthetic pathways that will not match the scope of
pharmacological classification.

9. Classification of bioactive compounds
Bio-active compounds of plants are divided into three main
categories:
(a) terpenes and terpenoids (approximately 25,000 types),
(b) alkaloids (approximately 12,000 types) and
(c) phenolic compounds (approximately 8000 types).

10. Terpene Terpenoid

11. Alkaloid

12. •Phenol

13. Synthesis of bioactive compounds
• Most bioactive compounds belong to one of a number of families, each of whi
particular structural characteristics arising from the way in which they are buil
nature (biosyn thesis).
• There are four major pathways for synthesis of secondary metabolites o
compounds:
• (1) Shikimic acid pathway,
• (2) malonic acid pathway,
• (3) Mevalonic acid pathway and
• (4) non-mevalonate (MEP) pathway

14. Synthesis of bioactive compounds
Alkaloids are produced by aromatic amino acids (come from
shikimic acid pathway) and by aliphatic amino acids (come from
tricarboxylic acid cycle).
Phenolic compounds are synthesized through shikimic acid
pathway and malonic acid pathway.
Through mevalonic acid pathway and MEP pathway terpenes are
produced.

15. A simplified view of pathways for production of three major groups of plant bioactive compounds

16. Extraction of bioactive
compounds

17. Extraction of bioactive compounds
Extraction of bioactive compounds refers to the process of isolating or
obtaining specific molecules or compounds from natural sources,
such as plants, animals, or microorganisms, which possess biological
activity and potential health benefits. These bioactive compounds can
include various classes of molecules such as polyphenols, alkaloids,
flavonoids, terpenoids, and essential oils, among others.

18. Extraction of bioactive
compounds
It is only possible to conduct further separation, identification, and
characterization of bioactive compounds followed by an appropriate
extraction process. Different extraction techniques should be used in
diverse conditions for understanding the extraction selectivity from
various natural sources.

19. Objectives Extraction of bioactive
compounds
• to extract targeted bioactive compounds from complex plant sample,
• to increase selectivity of analytical methods
• to increase sensitivity of bioassay by increasing the concentration of targeted
compounds,
• to convert the bioactive compounds into a more suitable form for detection and
separation, and
• to provide a strong and reproducible method that is inde pendent of variations in
the sample matrix.

20. Methods/ techniques of Extraction of bioactive
compounds
Conventional Non-Conventional

21. Conventional extraction techniques
Conventional extraction techniques of bioactive compounds refer to the established
methods used to isolate valuable and biologically active substances from natural
sources such as plants, animals, and microorganisms. These techniques are designed
to efficiently extract desired compounds while minimizing damage or degradation to
the target molecules. Conventional extraction methods often involve the use of
solvents, physical separation processes, and sometimes heat or pressure to extract
bioactive compounds from raw materials.

22. Conventional extraction
techniques
Bioactive compounds from plant materials can be extracted by various
classical extraction techniques. Most of these techniques are based on
the extracting power of different solvents in use and the application of
heat and/or mixing. In order to obtain bioactive compounds from plants,
the existing classical techniques are:
• Soxhlet extraction,
• Maceration and
• Hydro-distillation.

23. Soxhlet Extraction:
• This technique involves continuous extraction using a
cycle of solvent evaporation and condensation. The
sample is placed in a thimble, which is repeatedly
submerged in the solvent. The solvent vaporizes, rises,
and condenses in a separate chamber, carrying the
extracted compounds with it.

24. Maceration
This method involves soaking the source material in a solvent to
allow the bioactive compounds to diffuse into the solvent over
time. The resulting mixture is then filtered to separate the extract
from the solid residue.
1.Grinding plants makes them tiny for better mixing with solvent.
2.In maceration, solvent is added to closed vessel.
3.Liquid is strained, then solid residue is pressed to get more
solution.
4.The strained and pressed liquid is filtered to remove impurities.
5.Shaking helps extract more by increasing diffusion and bringing
fresh solvent in contact with the sample.

25. Hydro-distillation
Hydro distillation is a traditional method for extraction of bioactive compounds and
essential oils from plants. Organic solvents are not involved, and it can be performed
before dehydration of plant materials. There are three types of hydro distillation: water
distillation, water and steam distillation and direct steam distillation
1. Pack plant materials in a still.
2. Add water and bring to a boil or inject steam directly.
3. Heat releases bioactive compounds.
4. Cool the vapor mixture, condensing it.
5. Separate oil and bioactive compounds from water in a separator.

26. Non-conventional extraction techniques
Non-conventional extraction techniques refer to methods of extracting
substances or components from raw materials using approaches that
diverge from traditional extraction methods such as solvent extraction or
distillation. These techniques often involve innovative or alternative
processes that may offer advantages such as increased efficiency, reduced
environmental impact, or the ability to extract substances that are difficult
to isolate using conventional methods.

27. Non-conventional extraction techniques
1.Supercritical fluid extraction (SFE): In SFE, a substance is extracted using a solvent in a supercritical
state, where it exhibits properties of both a liquid and a gas. Supercritical fluids offer enhanced solubility
and diffusivity, making them effective for extracting compounds from various matrices such as plants,
foods, and pharmaceuticals.
2.Microwave-assisted extraction (MAE): MAE utilizes microwave energy to heat the extraction solvent
and the sample, facilitating the release of target compounds. This technique often requires shorter
extraction times and can be more energy-efficient compared to conventional methods.
3.Ultrasound-assisted extraction (UAE): UAE applies ultrasonic waves to the sample and solvent,
promoting the disruption of cell walls or matrices and enhancing mass transfer. It is particularly useful for
extracting bioactive compounds from plant materials and has the advantage of being a rapid and
environmentally friendly technique.

28. 4. Pressurized liquid extraction (PLE): PLE involves using high pressure and temperature to extract
compounds from solid samples. By employing elevated pressure, PLE can increase the solubility of
target compounds and enhance extraction efficiency compared to conventional methods.
5. Enzyme-assisted extraction: Enzymes are utilized to break down cell walls or tissues, facilitating
the release of desired compounds from raw materials. This method is often used in the extraction of
bioactive compounds from plant materials and can be selective, efficient, and environmentally friendly.
6. Solid-phase microextraction (SPME): SPME involves the use of a coated fiber to extract
compounds from the sample matrix without the need for solvents. The compounds are then desorbed
from the fiber and analyzed using various analytical techniques. SPME is particularly useful for
analyzing volatile and semi-volatile compounds.
Non-conventional extraction techniques

29. Solvent Extraction Method
• Solvent extraction, also known as liquid-liquid extraction or partitioning, is a
method used to separate compounds based on their relative solubilities in two
immiscible liquids.
• Liquid–liquid extraction, also known as solvent extraction and partitioning, is a
method to separate compounds or metal complexes, based on their relative
solubilities in two different immiscible liquids, usually water (polar) and an organic
solvent (non-polar).

30. Solvent Extraction Method Principle
• Solubility: separate compounds based on their relative solubilities in two immiscible
liquids.
• Polarity: The basic principle behind solvent extraction is the distribution of a solute (the
substance to be extracted) between two immiscible phases, typically a polar solvent
(aqueous phase) and a nonpolar solvent (organic phase). The solute will partition between
these two phases according to its solubility in each solvent.

31. Example of some extracted bioactive compounds by
different solvents
Water Ethanol Methanol Chloroform Dichloromethanol Ether Acetone
Anthocyanins,
Tannins
Saponins
Terpenoids
Tannins
Polyphenols
Flavanols
Terpenoids
Alkaloids
Anthocyanin
Terpenoids
Saponins
Tannins
Flavones
Polyphenols
Terpenoids
Flavonoids
Terpenoids Alkaloids
Terpenoids
Flavonoids

32. References
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sonochemistry, 8(3), 303-313.

 Paulsen, B. S. (2010). Highlights through the history of plant medicine. Bioactive compounds in plants-benefits and risks for man
and animals, 50.
 Bernhoft, A. J. A. B. (2010). A brief review on bioactive compounds in plants. Bioactive compounds in plants-benefits and risks for
man and animals, 50, 11-17.
 Taiz, L., & Zeiger, E. (2006). Secondary metabolites and plant defense. Plant physiology, 4, 315-344.
 Smith, R. M. (2003). Before the injection—modern methods of sample preparation for separation techniques. Journal of
chromatography A, 1000(1-2), 3-27.
 Croteau, R., Kutchan, T. M., & Lewis, N. G. (2000). Natural products (secondary metabolites). Biochemistry and molecular biology
of plants, 24, 1250-1319.
 Soxhlet, F. V. (1879). Die gewichtsanalytische bestimmung des milchfettes. Polytechnisches Journal, 232(5), 461-465.
 Vankar, P. S. (2004). Essential oils and fragrances from natural sources. Resonance, 9, 30-41.
 Cowan, M. M. (1999). Plant products as antimicrobial agents. Clinical microbiology reviews, 12(4), 564-582.

33. Questions

34. Thank you