Tu 1900 spectrophotometer

According to the methods of Ghobadi et al. [27 (link)], fresh lily leaves (0.2 g) were used to determine chlorophyll content by a TU-1900 spectrophotometer (Shimadzu, Kyoto, Japan). The sample was soaked in 10 mL of 80% acetone in a dark place for 48 hours. After that, the chloroplast pigment extract was obtained, and the wavelength of TU-1900 spectrophotometer was adjusted to 663 and 645 nm for the determination of chlorophyll content. The chlorophyll and carotenoid content was calculated according to the following formula: chlorophyll a = 12.7OD₆₆₃-2.59OD₆₄₅, chlorophyll b = 22.9OD645−4.67OD₆₆₃. Carotenoid = 1000*0.2*470–2.05Ca—114.8Cb/245.
The chlorophyll fluorescence parameters of Lanzhou lily plants were measured by the chlorophyll fluorescence imaging system (IMAG-PAM, Heinz Waltz, Germany) after being treated in the dark for about 30 minutes.

Optical rotations were recorded on a Perkin–Elmer 341-MC digital polarimeter at room temperature. A TU-1900 spectrophotometer (Shimadzu Europa GmbH, Duisburg, Germany) was used for obtaining the UV/Vis spectrum; IR spectra were scanned using a Hitachi 260–30 spectrometer. A Jasco J-810 circular dichroism spectropolarimeter was used to measure the ECD spectra at room temperature. 1D- and 2D-NMR spectra were obtained on a Bruker ARX-600 spectrometer (Bruker Technology Co., Ltd., Karlsruhe, Germany). The HRESIMS spectra were acquired using the UPLC/xevo G2 Qtof spectrometer (Waters Corporation, Milford, MA, United States). Semi-preparative HPLC was conducted on an Agilent 1,260 liquid chromatography (Santa Clara, CA, United States) with an Agilent C₁₈ column (250 mm × 34 mm). Silica gels (80–100 and 300–400 meshes) were obtained from Qingdao Marine Chemical Inc. (Qingdao, China). All analytical-grade solvents were obtained from Shanghai Titan Scientific Co., Ltd., Shanghai, China. HPLC-grade methanol and acetonitrile were purchased from Merck KGaA (Darmstadt, Germany).