Yuda_2012_J.Food.Sci_77_H254

Polyphenols, retained in black tea wastes following the commercial production of tea beverages, represent an underutilized resource. The purpose of this study was to investigate the potential use of hot-compressed water (HCW) for the extraction of pancreatic lipase-inhibiting polyphenols from black tea residues. Black tea residues were treated with HCW at 10 degreesC intervals, from 100 to 200 degreesC. The resulting extracts were analyzed using high-performance liquid chromatography-mass spectrometry and assayed to determine their inhibitory effect on pancreatic lipase activity in vitro. Four theaflavins (TF), 5 catechins, 2 quercetin glycosides, quinic acid, gallic acid, and caffeine were identified. The total polyphenol content of extracts increased with increasing temperature but lipase inhibitors (TF, theaflavin 3-O-gallate, theaflavin 3'-O-gallate, theaflavin 3,3'-O-gallate, epigallocatechin gallate, and epicatechin gallate) decreased over 150 degreesC. All extracts inhibited pancreatic lipase but extracts obtained at 100 to 140 degreesC showed the greatest lipase inhibition (IC(50) s of 0.9 to 1.3 microg/mL), consistent with the optimal extraction of TFs and catechins except catechin by HCW between 130 and 150 degreesC. HCW can be used to extract pancreatic lipase-inhibiting polyphenols from black tea waste. These extracts have potential uses, as dietary supplements and medications, for the prevention and treatment of obesity.