Optimization of Microwave Vacuum Drying and Pretreatment Methods for Polygonum cuspidatum

Constituents from Polygonum cuspidatum.

Two lignan sulfates, a stilbene derivative and a phenol sulfate, together with 10 known compounds, were isolated from an aqueous extract of the root of Polygonum cuspidatum. The new compounds were elucidated based on chemical evidence and spectroscopic techniques including two-dimensional NMR methods. They exhibited no inhibition of lipid peroxidation and no cytotoxic and DNA cleavage activities.

Selezione Bibliografica Su Polygonum Cuspidatum E Resveratrolo

Antioxidant activity of extract from Polygonum cuspidatum.

Numerous diseases are induced by free radicals via lipid peroxidation, protein peroxidation and DNA damage. It has been known that a variety of plant extracts have antioxidant activities to scavenge free radicals. Whether Polygonum cuspidatum Sieb. et Zuce has antioxidant activity is unknown. In this study, dried roots of Polygonum cuspidatum were extracted by ethanol and the extract was lyophi...

Effect of Ultrasound Pretreatment on Wood Prior to Vacuum Drying♠

The influence of ultrasonic pretreatment prior to vacuum drying of Chinese fir specimens was examined in this work. In the pretreatments, wood samples were immerged in a distilled water bath and were treated using two wave frequencies for four different elapsed times to investigate effects of ultrasonic frequency and treatment duration. Then the wood samples were vacuum-dried at 80°C and absolu...

Microwave Assisted Vacuum Drying and Endpoint Determination Using Mass Spectrometry

Microwave drying technology has the potential for large production time and energy cost savings versus traditional vacuum drying methods for active pharmaceutical ingredient (API) applications. One of the most critical parameters in the drying process is the determination of the end point, usually at a specified moisture content. On-line mass spectrometry (MS) was used as a tool to monitor micr...