Lc 10avp series

Analytical HPLC was performed on a Shimadzu LC-10Avp series HPLC system consisting of an autosampler, high-pressure pumps, column oven and PDA. HPLC conditions: C18 column (Eurospher 100-5, 250 × 4.6 mm) and gradient elution (MeCN/0.1 % (v/v) TFA 0.5/99.5 in 30 min to MeCN/0.1 % (v/v) TFA 100/0, MeCN 100 % for 10 min), flow rate 1 mL min⁻¹. Preparative HPLC was performed on a Shimadzu LC-8a series HPLC system with PDA. LC-MS measurements were performed using an Exactive Orbitrap High Performance Benchtop LC-MS with an electrospray ion source and an Accela HPLC system (Thermo Fisher Scientific, Bremen). HPLC conditions: C18 column (Betasil C18 3 µm 150 × 2.1 mm) and gradient elution (MeCN/0.1 % (v/v) HCOOH (H₂O) 5/95 for 1 min, going up to 98/2 in 15 min, then 98/2 for another 3 min; flow rate 0.2 mL min⁻¹). NMR spectra were recorded on a Bruker AVANCE III 600 MHz instrument equipped with a Bruker cryo platform. The residual solvent signals were used as an internal reference.

The HPLC method previously described by Lakshminarayana et al.^{66 (link)} was followed to estimate carotenoid profiles in A. gangeticus leaf samples. A variable Shimadzu SPD-10Avp UV–Vis detector, LC-10Avp binary pumps, and a degasser (DGU-14A) were equipped with the HPLC system (Shimadzu SCL10Avp, Kyoto, Japan). Briefly, the carotenoids were separated on a CTO-10AC (STR ODS-II, 150 × 4.6 mm I.D., Shinwa Chemical Industries, Ltd., Kyoto, Japan) column. The carotenoids were separated using acetonitrile/methanol/dichloromethane (60:20:20, v/v/v) containing 0.1% ammonium acetate as a mobile phase. For HPLC analysis, 20 µL samples were injected under the isocratic condition at a flow rate of 1 mL min⁻¹. The Shimadzu SPD-10Avp UV–Vis detector was set at 450 nm. We confirmed the peak of carotenoids by comparing their retention time of standard chromatograms recorded with a Shimadzu model LC-10Avp series equipped with SPD-10Avp detectors. At the same time, the characteristic spectrum record with a PDA detector was taken to confirm the λ_max values of these compounds. We quantified the carotenoid profiles estimating their peak areas to respective reference standards.