Ang et al., "Potent a-glucosidase
and [alpha]-amylase inhibitory activities of standardized 50% ethanolic extracts and sinensetin from Orthosiphon stamineus Benth as anti-diabetic mechanism," BMC Complementary and Alternative Medicine, vol.
, acarbose, 3,5-dinitrosalicylic acid (DNS), Folin-Ciocalteu reagent, gallic acid, p-nitrophenyl a-D-glucopyranoside (PNPG) and starch purchased from Sigma Chemical Co.
The preliminary inhibitory results (Table 1) displayed that the hydroxycinnamoyl amides (11, 16) were similar in potency to acarbose, whereas the lead compounds (1, 2, 5, 6, 9, 14, and 15 and sinapic acid) were the most potent a-glucosidase
Hypoglycemic activity of the antioxidant saponarin, characterized as a-glucosidase
inhibitor present in Tinospora cordifolia.
Fang et al (2009) reported six positive clones showing a-glucosidase
activity, through functional screening of a metagenomic library of the microbes from the surface water of South China Sea.
Response variables [X.sub.1] [X.sub.2] [X.sub.3] Yield of extraction (%) 48.80 74.29 25.09 Total polyphenol content (%) 50.11 72.06 22.73 PTP-1B inhibition rate (%) 52.10 73.80 21.84 a-glucosidase
inhibition rate (%) 47.57 69.74 22.22 ABTS inhibition rate (%) 52.70 71.50 22.38 Response variables [X.sub.4] Predicted values Yield of extraction (%) 3.04 40.84 Total polyphenol content (%) 2.93 48.44 PTP-1B inhibition rate (%) 2.95 86.21 a-glucosidase
inhibition rate (%) 3.03 96.56 ABTS inhibition rate (%) 3.01 77.68 [X.sub.1], ethanol concentration (%); [X.sub.2], temperature ([degrees]C); [X.sub.3], sample/to/solvent ratio (w/v); [X.sub.4], extraction time (h).
C.sakazakii appears to constitutively express high levels of a-glucosidase
. This enzyme hydrolyses the chromogenic substrate 5-bromo-4-chloro-3-indolyl-a-D-glucopyranoside present in the medium, producing green to blue-green coloured colonies.
Assay of acid a-glucosidase
for the NBS of Pompe disease is problematic because of the presence of the interfering enzyme maltase-glucoamylase, which, like the Pompe enzyme, displays activity in the low pH range and is present in DBS.
These exhibited significant inhibitory potency against a-glucosidase
with [IC.sub.50] 8.09 [+ or -] 0.023 and 9.77 [+ or -] 0.032 [micro]M, respectively (Table 1) and against [alpha]-amylase with [IC.sub.50] 73.60 [+ or -] 0.48 and 39.69 [+ or -] 0.39 [micro]M, respectively (supplementary Table 1).
Moreover, in-vitro a-glucosidase
inhibition assay of the complex with acarbose as control revealed its anti-diabetic potential with IC50 value of 13.1 uM.
A previous report  found that galloyl substitution (more than three substitutions at the 1,5-anhydroglucitol core) resulted in potent inhibition of a-glucosidase
, with a galloyl group at C-6 being essential for this activity.
The maximum CMCase activity 0.25 IU/ ml, exoglucanase 0.03 IU/ml, a-glucosidase
0.20 IU/ ml, FPase 0.20 IU/ml were observed after 96 hours, When Ammonium sulphate applied at 0.14 gm% (Figure 7).