Rapid identification of Dendrobium officinale using Loop-Mediated Isothermal Amplification (LAMP) method

Area of Science:

• Botany
• Molecular Biology
• Pharmacognosy

Background:

• Dendrobium officinale is a valuable medicinal herb in Traditional Chinese Medicine.
• Accurate identification of D. officinale is challenging due to its similarity to other Dendrobium species.
• Misidentification can lead to the use of ineffective or adulterated medicinal products.

Purpose of the Study:

• To develop a rapid and accurate identification protocol for Dendrobium officinale.
• To differentiate D. officinale from commonly used adulterants using molecular methods.
• To provide a tool for quick on-site verification of medicinal Dendrobium species.

Main Methods:

• Development of a loop-mediated isothermal amplification (LAMP) assay targeting a specific internal transcribed spacer region of D. officinale.
• Optimization of reaction conditions, including temperature (65 °C) and time (40 min).
• Visual detection of amplification using SYBR® Green I dye, resulting in an observable color change (orange to green) in positive samples.

Main Results:

• The LAMP assay successfully amplified D. officinale DNA within 40 minutes.
• A distinct color change from orange to green was observed in D. officinale samples, absent in adulterants.
• Specificity was confirmed by testing 17 D. officinale samples and 32 adulterant samples, showing no cross-amplification with non-target species.

Conclusions:

• The developed LAMP-based method provides a rapid, accurate, and specific means for identifying Dendrobium officinale.
• The visual colorimetric detection requires no specialized equipment, making it suitable for field applications.
• This methodology enhances the quality control of medicinal herbs and prevents adulteration in Traditional Chinese Medicine.