1. Thẩm âm dược liệu bằng kiềm (NH₄OH, NaOH, Na₂CO₃)

The images illustrate a flowchart outlining methods for extracting alkaloids from plant materials using various solvents and reagents. Here’s a brief breakdown of the process:

1. **Starting Material**: Plant material containing alkaloid salts (acidic form).
2. **Extraction**:
- Use of alkaline solutions (NH₄OH, NaOH, Na₂CO₃) for the initial extraction.
- Solvent extraction methods like using CHCl₃, ether, or benzene.
- Separation of base form of alkaloids and subsequent acid extraction.
3. **Purification**:
- Adjust pH between 9 to 10.
- Further purification to isolate non-polar alkaloids.

The chart provides guidance on the chemical steps required to isolate and convert alkaloids during the extraction process. If you have specific questions about any part of the process, feel free to ask!