Flavonoids isolated from Syzygium aqueum leaf extract as potential antihyperglycaemic agents

Structure–activity relationship of immunomodulating pectins from elderberries

“…However, these results are in contrast to the activity of anthocyanins compared to their aglycone. A study performed by Manaharan et al [141] reported that myricetin 3-O-rhamnoside showed stronger inhibition of α-amylase than of myricetin. Overall, it is difficult to draw general or universally applicable comments regarding the impact of glycosylation on flavonoids' and anthocyanins' biological benefits.…”

Starch Hydrolase Inhibitors from Edible Plants

“…Apparently, substituting the 3-OH group with glycosyl moiety greatly decreased the inhibition activity by over 10 times. A structurally similar compound, myricetin-3-O-rhamnoside (9) and europetin-3-O-rhamnoside (10) showed much stronger yeast a-glucosidase inhibition activity with IC 50 values of 1.1 and 1.9 mM (Manaharan et al, 2012). However, one has to interpret this data with caution because the possibly different experimental conditions applied and the lack of a reference standard.…”

“…Using the turbidity assay we developed in our lab, we could not detect any inhibition activity of quercetin against pancreatic a-amylase using acarbose as the reference standard (Huang et al, unpublished results). Therefore, it needs to be verified if the EC 50 reported is method dependent to rule out potential artifact (Manaharan et al, 2012). Cleistocalyx operculatus also belongs to Myrtaceae family.…”

Simple ITC method for activity and inhibition studies on human salivary α-amylase

“…Methods for amylase activity measurements using starch as substrate generally utilise different reducing sugar assays, e.g. 3,5-dinitrosalicylic acid (DNS) assay 23 , which similarly to other starch-based methods like starch azure 24 and Lugol method 25 , provide coloured products to the spectrophotometric detection. Amylase kits for diagnostic purposes use chromophore-containing substrates (occasionally with protecting group 26 ) in coupled assays, when the liberation of chromophore is measured also with spectrophotometer 27 .…”