The sulfonium sulfate compounds all appear to possess alpha-glucosidase inhibitory properties, and may prevent the absorption of dietary carbohydrates.
Salacinol appears to have an IC50 value of 5.2-6uM (maltase), 1.3-1.6uM (sucrase), and 1.3uM (isomaltase);[1] the efficacy of salacinol, relative to acarbose (pharamceutical control) are slightly lesser, approximately equal, and more potent; respectively on these three enzymes.[18] When ingested orally at doses of 0.3-5mg/kg in rats fed a mixed maltose and sucrose meal, Salacinol appears to be able to reduce the serum levels of glucose at higher doses.[2] Neosalacinol (derivative of salacinol) appears to be slightly less efficient in inhibiting maltase with an IC50 value of 8-22.2uM, approximately equal with sucrase at 1.3-2.5uM, and more effective at isomaltase with 0.3-0.68uM.[18]
The compounds named after the plant, the salacinols, appear to be highly effective in inhibiting carbohydrate digestive enzymes even when in isolation
Kotalanol appears to be more effective than Salacinol,[19] with IC50 values against maltase, sucrase, and isomaltase of 2uM, 0.43uM, and 1.3uM respectively.[1] Neokotalanol is approximately as effective, with IC50 values against maltase, sucrase, and isomaltase of 1.6uM, 1.5uM, and 0.46uM.[1]
Due to the low molecular weight of these molecules, the concentration range of how much of these molecules is required to reach IC50 values tends to be under 1mcg/mL; with the only real expection to this general rule being Neosalacinol requiring up to 5.65mcg/mL for maltase inhibition.[1]
The related molecules, the kotalanols, appear to be slightly more effective when compared on a per-weight basis
The large molecule known as 13-MRT also possesses activity in inhibiting carbohydrate digestive enzymes, with an IC50 value of 0.19uM and 0.23uM against sucrase and maltase, respectively.[2] This compound shows efficacy at doses of 150-900mcg/kg oral ingestion in reducing the spike in blood glucose form a meal consisting of sucrose and maltose, attenuated the spike in blood glucose from a starch meal, and had no effect on a glucose-only meal; it was more potent than isolated Salasinol (1.25-5mg/kg) but weaker than voglibose (100-200mcg/kg).[2] 13-MRT appears to be the most effective isolated molecule from Salacia Reticulata in inhibiting carbohydrate absorption.[6]
Finally, Mangiferin (which exists at 0.9-2.3% of the water extract of Salacia Reticulum) appears to also inhibit sucrase and isomaltase (but not maltase) with IC50 values of 87mcg/mL and 216mcg/mL.[8] Mangiferin appears to be the most potent Sucrase inhibitor (with less ability on maltase enzymes), and its content is highly correlated (r=0.934) with the efficacy of the whole plant extract on sucrase.[8]
A wide variety of individual ingredients in Salacia species appear to be remarkably potent carbohydrate digestive enzyme inhibitors in vitro, which may precede the plant's efficacy in treating the early stages of diabetes
In regards to using the plant extract, Salaca Reticulum root extract appears to be the most effective overall extract.[1] The IC50 value of Reticulata against maltase and sucrase appears to be 89.4mcg/mL and 36.6mcg/mL, which is more efficient than the other two main species. The efficacy of Salacia Oblonga and Chinensis (roots) are 162.1ug/mL and 154.8ug/mL (respectively, against maltase) and 59.8ug/mL and 55.9ug/mL (respectively, against sucrase).[1] The leaf and fruit extracts do not appear to be significantly effective.
An aqueous extract of Salacia Reticulata, in rats fed 10-75mg/kg of it, appears to be able to reduce the spike in blood glucose from sucrose or maltose in a relatively dose-dependent manner.[2]
The mixed root extract itself carries the benefits of all the individual components, with similar efficacy