ABSTRACT
OBJECTIVE: The root of Helicteres angustifolia L. (Sterculiaceae) has been used as tea to treat diabetics effectively by local people in Laos. However, no scientific evidence is available for this ethnomedicinal usage. This study was undertaken to explore the hypoglycemic effect of aqueous extract from Helicteres angustifolia root. PATIENTS AND METHODS: The effect of aqueous extract from Helicteres angustifolia root on glucose consumption in C2C12 myotubes was investigated at a dose of 25, 50 and 100 µg/mL, respectively. The alpha-glucosidase inhibitory activity of the extract was evaluated using rat intestinal maltase and sucrose. Moreover, oral sucrose tolerance test (OSTT) in normal and streptozotocin induced diabetic rats was performed. Finally, their cytotoxicity in C2C12 cells and acute oral toxicity in rats was analyzed. RESULTS: Aqueous root extract of Helicteres angustifolia significantly enhanced glucose consumption in C2C12 myotubes. The extract also significantly inhibited rat intestinal maltase (IC50 = 1.44 ± 0.24 mg/mL) and sucrase activity (IC50 = 0.54 ± 0.12 mg/mL), respectively. The OSTT results showed that the extract significantly suppressed the increase of blood glucose levels in normal and diabetic rats. The extract was also proven to have low acute toxicity (LD50 > 5 g/kg) and low cytotoxicity in C2C12 cells (IC50 > 0.4 mg/mL). CONCLUSIONS: The findings from this study indicate that aqueous root extract of Helicteres angustifolia possesses significant alpha-glucosidase inhibitory activity and moderate enhanced glucose consumption activity, while with low cytotoxic and acute toxicity.
Subject(s)
Glucose/metabolism , Malvaceae/chemistry , Plant Extracts/chemistry , alpha-Glucosidases/metabolism , Animals , Blood Glucose/analysis , Cell Line , Cell Survival/drug effects , Diabetes Mellitus, Experimental/drug therapy , Glucose Tolerance Test , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Intestines/enzymology , Male , Malvaceae/metabolism , Mice , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plant Roots/chemistry , Plant Roots/metabolism , Rats , Rats, Sprague-Dawley , Water/chemistry , alpha-Glucosidases/chemistryABSTRACT
The application of atrazine in China during the last ten years has led to some environmental problems. In this paper, the multimedia model of atrazine in soil-plant-groundwater system at Baiyangdian Lake area in Northern China was established using a fugacity approach, and verified with observed values. The model involved 7 environmental compartments which are air, groundwater, soil, corn roots, corn stem, corn leaf and kernel of corn. The results showed that the relative errors between calculated and observed values have a mean value of 24.7%, the highest value is 48% and the lowest value is 1.4%. All these values indicated that this multimedia model can be used to simulate the environmental fate of atrazine. Both the calculated and observed values of concentrations of atrazine in plant compartments are in the following order: in corn roots > in corn stem > in kernel of corn > in corn leaf, it exhibited a good regularity. The prediction results indicated that concentrations of atrazine in the groundwater and kernel of corn will override the limitation of 3 micrograms/L and 0.05 mg/kg respectively.
Subject(s)
Atrazine/pharmacokinetics , Herbicides/pharmacokinetics , Models, Theoretical , Multimedia , Atrazine/analysis , Forecasting , Herbicides/analysis , Plant Roots , Plants , Soil Pollutants , Tissue Distribution , Water Pollutants , Zea mays/chemistryABSTRACT
The hydrolysis kinetics of atrazine in distilled water and leaching water from soil, and their influence factors were studied by incubation at 35 degrees C and HPLC analysis method. The kinetic process of atrazine hydrolysis can be described by the first-order reaction law. The results showed that the hydrolysis rate constants k in leaching water and distilled water were 1.606 x 10(-3)/d and 1.055 x 10(-3)/d, respectively; the half-life of atrazine hydrolysis in distilled water at pH 3, pH 4.5 and pH 8 were 373 days, 522 days and 657 days respectively. The results also showed that the proton in reaction solution can catalyze the atrazine hydrolysis; humic acid and NH4+ etc. substances in aqueous solution can facilitate atrazine hydrolysis; rate constants of atrazine hydrolysis with humic acid and NH4NO3 were 2.431 x 10(-3)/d and 1.498 x 10(-3)/d respectively which were 2.3 and 1.42 times of control (1.055 x 10(-3)/d); anion NO3- can inhibit catalysis of humic acid to atrazine hydrolysis.
Subject(s)
Atrazine/chemistry , Herbicides/chemistry , Soil Pollutants , China , Electrophoresis, Polyacrylamide Gel , Humic Substances/chemistry , Hydrolysis , Kinetics , Nitrates/chemistry , Sodium Azide/chemistry , Surface-Active Agents/chemistryABSTRACT
In this paper, the concentration distribution and environmental fate of atrazine in a crop-soil-groundwater system at Baiyangdian Lake area of North China were studied. The concentration of the herbicide in spatial and vertical soils, and in roots, stem, leaf, corncob and kernel of corn, and in groundwater were measured by HPLC. The results showed that the variation of spatial concentration of atrazine in soil can be described by first-order kinetics equation which has a half-life of 360 days and a rate constant of 0.0019 d-1. The vertical variation of atrazine concentration with soil depth follows the exponential decay law. After 120 days following atrazine application, the mass distributions of this herbicide in crop-soil-groundwater system are 71% in soil, 20% in groundwater and 1% in crop respectively, and 8% due to loss by degradation or often removal processes. The order of atrazine concentration in every part of corn crop is in roots > in corncob > in kernel of corn > in leaf.
