title: Box-Behnken design for optimum extraction of biogenetic chemicals from P. lanceolata with an energy audit (thermal × microwave × acoustic): a case study of HPTLC determination with additional specificity using on-line/off-line coupling with DAD/NIR/ESI-MS.
abstract: BACKGROUND
  The genus Pluchea comprises about 80 species distributed worldwide, out of them, only Pluchea lanceolata (DC.) Oliv. & Hiern, is used extensively in the traditional system of India. No chromatographic method is available for its quality.
  
  
  OBJECTIVE
  To perform the energy audit for the extraction of biogenetic pentacyclic triterpene, its acetate and sterol from P. lanceolata utilising organic and four alternative solvents. Additionally to resolve the uncertainty of TLC determination, on-line/off-line coupling with a diode-array detector (DAD), and near-infrared (NIR) and electrospray ionisation (ESI) MS was introduced.
  
  
  METHODS
  The extraction of taraxasterol (Tx), taraxasterol acetate (TxAc) and stigmasterol (St) from P. lanceolata was performed using three energy modes. The effects of different operating parameters were studied for optimum extraction yield using the design of experiments, that is, the central composite design and Box-Behnken design. In addition to the retention factor (Rf ) and visible spectral matching, two additional optical spectroscopic techniques, that is, NIR and ESI-MS, were applied for extended specificity.
  
  
  RESULTS
  The method was developed for Tx, TxAc and St determination using HPTLC at 645 nm. The optimum extraction yield of targeted compounds was found to be higher with organic solvents than eco-friendly surfactants. The pulse ultrasonic assisted extraction (PUAE) has resulted in optimum extraction of compounds comparable to hot extraction. Both NIR and ESI-MS provided extended specificity in determination.
  
  
  CONCLUSIONS
  The 5/1-PUAE was determined to be effective, reproducible, simple and energy efficient for the determination of Tx, TxAc and St in P. lanceolata. The offline coupling of NIR and ESI-MS with HPTLC led to considerable improvement in specificity.
authors.affiliation: Analytical Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP), Lucknow, 226015, India.
authors.forename: Pooja
authors.initials: P
authors.lastname: Srivastava
authors.forename: P V
authors.initials: PV
authors.lastname: Ajayakumar
authors.forename: Karuna
authors.initials: K
authors.lastname: Shanker
mesh_terms: D019659:Asteraceae / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D008872:Microwaves; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D012997:Solvents; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D013261:Sterols / Q000737:chemistry / Q000302:isolation & purification*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification*; D014465:Ultrasonics
chemical_list: D010936:Plant Extracts; D012997:Solvents; D013261:Sterols; D014315:Triterpenes; C092740:taraxasteryl acetate; C079988:taraxasterol
keywords: Box-Behnken design (BBD); Genopol X-80; HPTLC/DAD/NIR/ESIMS; Pluchea lanceolata; cloud-point extraction; response surface method (RSM); taraxasterol acetate (TxAc)