RESUMO
OBJECTIVE: To establish the UV spectrophotometry for determining lignin content in tiny Panax ginseng powder. METHODS: Classical Klason method and UV spectrophotometry were used. RESULTS: The lignin contents measured by UV spectrophotometry were higher, more repeatable and accurate as comparison with the Klason method. The specific absorptance peak of ginseng lignin appeared at 260 nm. The acetyl bromide treatment of the UV spectrophotometry was processed for ginseng powder at 70 degrees C for 30 minutes. It is also concluded that the lignin contents were obvious different among various ginsengs. CONCLUSION: UV spectrophotometry is simple, accurate and just need a little materials. It is especially suitable to determine the lignin content for ginseng and other precious Chinese traditional medicines.