MICELLAR EXTRACTION AND CLOUD-POINT PRECONCENTRATION OF LABDANE DITERPENOIDS FROM ANDROGRAPHIS PANICULATA.

Micelle-mediated extraction and cloud-point preconcentration method was developed for the separation and determination of andrographolide (ANDRO) and neo-andrographolide (NEO) from Andrographis paniculata by planar and high performance liquid chromatography with photodiode array detection. Comparative efficiency and feasibility of employing non-ionic surfactants, namely, Triton X-100, Triton X-114, and Genapol X-80 as an alternative and effective solvent have been demonstrated. Ultrasonic assisted extraction, when compared with common organic solvents, at 5% surfactant (Triton X-100) concentration has yielded higher extraction efficiency of ANDRO and NEO than common organic solvents. The preconcentration factor was approximately 7.0 and the cloud-point extraction recoveries for the two labdane diterpenoids were 90.28 and 98.80%, respectively. The HPLC method consisting monolithic column and isocratic elution with water: acetonitrile (75:25, v/v) has shown advantages over C18 column, in terms of noninterference of surfactant peak elution. The elution was monitored with a photodiode array detector and quantitation was performed at 220 nm. The method has shown good sensitivities (LOD- 10, 30 µg/mL; LOQ- 33, 99 µg/mL of ANDRO and NEO, respectively). The results showed that micelle-mediated extraction and cloud-point preconcentration could be employed as an alternative and ecofriendly approach for the rapid analysis of targeted diterpenoids from A. paniculata. [ABSTRACT FROM AUTHOR]