Premium
Effects of Ginkgo biloba extract and its constituents on chemotaxis and cGMP‐dependent protein kinase activity in Tetrahymena thermophila
Author(s) -
CHEN F.,
LEICK V.
Publication year - 2005
Publication title -
journal of eukaryotic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.067
H-Index - 77
eISSN - 1550-7408
pISSN - 1066-5234
DOI - 10.1111/j.1550-7408.2005.05202003_4_1.x
Subject(s) - kaempferol , biology , rutin , tetrahymena , isorhamnetin , myricetin , quercetin , ginkgo biloba , biochemistry , genistein , pharmacology , antioxidant , endocrinology
Ginkgo biloba extract (GBE), which is one of the most sold herbal extracts in the world, is considered as a multifunctional material, which can promote radical scavenging activity and improve brain functioning. Although much research has carried out on its mechanisms against diseases, there is a need for further investigation for understanding molecular mechanisms, potential health benefits, and possible health risks. Recently, we have been developing an alternative screening method for studying phytochemical materials bioactivities with Tetrahymena thermophila as experimental organism. In this paper, the effects of GBE and its constituents were systematically investigated on chemoattraction and cGMP‐dependent protein kinase (PKG) in T. thermophila . GBE and its constituents exerted significant inhibitions of chemoattraction and PKG. The minimal concentrations to completely inhibit chemotaxis of T. thermophila were 2 mg/ml, 50, 25, 12, 100, 100, 400, 500, 300 and 400 μM for GBE, quercetin, kaempferol, isorhamnetin, myricetin, genistein, rutin, quercitrin, isoquercitrin and quercetin‐3‐ d ‐galactoside, respectively. The IC 50 values for PKG were 0.15 mg/ml, 26, 22, 19, 160, 132, 81 and 186 μM for GBE, myricetin, kaempferol, quercetin, isorhamnetin, genistein, rutin and isoquercitrin, respectively. The results indicate that the inhibitions of GBE and its constituents of chemotaxis of T. thermophila and their effects on PKG are rather similar. This suggests that the ciliate of T. thermophila may be a potential experimental organism in screening such bioactive phytochemicals.