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

Abstract

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.

Keywords:

• Andrographis paniculata
• cloud-point preconcentration
• genapol X-80
• micelle-mediated extraction
• triton X-100
• triton X-114

ACKNOWLEDGMENTS

This work was financially supported by the Young Scientists Research Projects (YSP-16) under major laboratory program (MLP 9.16) of the Institute. The authors are grateful to Professor Ramrajasekharan, Director, CIMAP and Dr. M. M. Gupta, Head, Analytical Chemistry for their critical comments, discussion, and kind support during the progress of the work. It is a pleasure to acknowledge the reviewers of the manuscript and the editors for their suggestions and comments.

Notes

^a Dry weight basis; NS–Not studied.

^b Cold percolation (3 × 15 mL, 10 h extraction time at room temperature).

^c Hot extraction (3 × 15 mL, 30 min extraction time at 50°C).

^d Ultrasonication (15 min extraction time).

^e Microwave (3 × 15 mL, 90 W, 50°C for 3 min extraction time).

^(a)NaCl (80 g/L).

^(b)(NH₄)₂SO₄ (50 g/L).