with an acetonitrile water gradient 80 water 20 acetonitrile containing 0 1 tfa to 60 water 40 acetonitrile containing 0 1 tfa over 20 mins gave rise to quercitrin 1 3 o rhamnospyranosylkaempferol 2 rhamnitrin 3 and rhamnocitrin 4 the purified compounds and extracts were made up 2 mg ml solutions in water using initially a drop of dmso if required for solubility human pancreatic lipase was diluted 1 5 5 prior to use the assay was carried out at 20 u00b0 c using 10 u03bcl test compound 5 u03bcl enzyme solution 90 u03bcl substrate and 30 u03bcl activator reagent color formation was measured at 550 nm after 30 minutes sigma u03b1 amylase a6255 porcine pancreatic amylase as saline suspension diluted to 35 units ml the assay was carried out at 20 u00b0 c using 10 u03bcl enzyme solution 10 u03bcl test compound and 150 u03bcl infinity reagent the rate of color formation was measured over five minutes after which the final absorbance was measured at 405 nm as an endpoint recording sigma u03b1 glucosidase g5003 from s cerevisiae at 2 units ml in phosphate buffer ph 6 0 sigma p nitrophenyl u03b1 d glucopyranoside 5 mm in phosphate buffer ph 6 0 the assay was carried out at 20 u00b0 c using 10 u03bcl enzyme solution 10 u03bcl test compound and 50 u03bcl substrate solution the reaction was carried out for 7 minutes color formation was measured at 415 nm following the addition of 80 u03bcl 0 4 m glycine solution ph 10 4 to stop the reaction other glycosidase assays were carried out using enzymes from sigma and appropriate p nitrophenyl substrates 7 uv vis u03bb max meoh nm log u03b5 200 264 342 1 h nmr 500 mhz meoh u03b4 ppm 0 79 3h.