Catalogo dei Corsi di studio

This course provides the student with the theoretical knowledge and technical skills of extraction and purification of natural products.
By completing the module Laboratory of natural products extraction, the student acquires:
1. Theoretical knowledge of the most common methods of extracting and purifying natural products (extraction methods, percolation, maceration, decotion, infusion, steam distillation, chromatography, and crystallization), of the most common instrumental chemical analysis techniques to determine physicochemical measurements (melting point, boiling point, density) through theoretical lecture-based classes, the volumetric analysis methods for determining natural products
2. The ability to apply that theoretical knowledge. The student attends individual teaching laboratory lectures where he applies extraction, purification and quantitative determination methods to natural products.
3. Self-direction and to act independently to a level where the student has a practical understanding of the learned techniques. At the end of each laboratory lecture the student has to prepare a report about the analysis procedure. Moreover, during the final test the student will exercise on mixture separation.
4. Written and oral communications skills, to a level where the student can clearly communicate the conclusions of extraction and purification process. This is evaluated during the final test.
5. To develop subject-related practical and cognitive skills. The course provides the student with the core elements for both further courses and the final test.

Programme

This course provides the student with the theoretical knowledge and technical skills of the extraction and purification of natural products.
Curriculum content of lecture-based classes:

Introduction: Natural products with pharmacological activity. (2 hours)
Extraction of natural products: Introduction and aims. Dereplication. (2 hours)
Extraction from plants and marine organisms: preliminary stages. (2 hours)
Extraction: Principles, partition coefficient, solvent choice, pH dependency, liquid-liquid extraction; continuous extraction; solid-liquid extraction; solid-liquid extraction with Soxhlet, supercritical extraction, microwave assisted extraction (MAE) and solid phase extraction (SPE). (4 hours)
Planning of of a natural compound the isolation (2 hours)
Percolation, maceration, decoction, infusion and steam distillation. (4 hours)
Separation of total extracts: interfering substances, high- and low-resolution separation, physicochemical determination of natural products, saponins and alkaloids separation. (4 hours)
Separation of total extracts: Crystallization. Chromatography: introduction; classification of chromatographic methods; mostly used solid and liquid stationary phases; separation mechanism (partition, expanded bed absorption, ion exchange, displacement, affinity). Planar chromatography on paper and TLC. Column chromatography. (10 hours)
Extraction from broth fermentation: principles, solid-liquid separation, centrifugation and filtration. (2 hours)
Individual teaching laboratory lectures (40 hours):

Adopted texts

Natural Products Isolation Edited by Richard J. P. Cannell
Fondamenti di farmacognosia e fitoterapia. M. Heinrich, J. Barnes

Prerequisites

For a better understanding of the theoretical knowledge and technical skills, the student must have learned: - General chemistry and organic chemistry, necessary prerequisites for understanding the theoretical knowledge of the extraction methods.

Exam modes

- At the end of the teaching laboratory lectures, the student has to prepare a report about the analysis procedure. Self-direction and to act independently will be evaluated.
- End-of-course exam: written exam. Exercise on mixture separation and evaluation of knowledge of the most common methods of extracting and purifying natural products (extraction methods, percolation, maceration, decotion, infusion, steam distillation, chromatography, and crystallization), of the most common instrumental chemical analysis techniques to determine physicochemical measurements (melting point, boiling point, density).