Novel Acylated Flavonol Tetraglycoside with Inhibitory Effect on Lipid Accumulation in 3T3-L1 Cells from Lu'an GuaPian Tea and Quantification of Flavonoid Glycosides in Six Major Processing Types of Tea.

A novel acylated flavonol tetraglycoside, kaempferol 3-O-[(E)-p-coumaroyl-(1→2)][α-l-arabinopyranosyl-(1→3)][β-d-glucopyranosyl (1→3)-α-l-rhamnopyranosyl(1→6)]-β-d-glucopyranoside (camellikaempferoside C, 1), together with 2 flavonols and 18 flavone and flavonol glycosides (FGs) (2-21) was isolated from the green tea Lu'an GuaPian (Camellia sinensis L.O. Kuntze). Their structures were identified by spectroscopic and chemical methods. Four acylated FGs (1, 7, 8, 9) were found to inhibit the proliferation and differentiation of 3T3-L1 preadipocytes at concentrations of 25, 50, and 100 μM (P < 0.05). Furthermore, we established a rapid UPLC method to quantify nine FGs in six major processing types of tea. The results showed that dark tea had the highest amount of 20 (0.70 ± 0.017 mg/g) and black tea had the highest amount of 8 (0.09 ± 0.012 mg/g), whereas the amounts of 10 and 16 basically decreased with the increasing degree of fermentation and could contribute to the discrimination of different processing types of tea.