Indian scientists, associated with the Council of Scientific and Industrial Research (CSIR) have received US patent for a novel method of using fruit fly (Drosophila melanogaster) as a model for screening psychostimulant plant materials for their efficacy as CNS stimulant/depressants. The new method is to find use in the drug research and development programmes.

The CSIR scientists Abhay Sharma, Amaresh Pandey, Subhash Singh and Sushil Kumar have successfully tested the extract of several plants including Acorus calamus for CNS stimulation/depression activity in the mutant fruit fly Drosophila melanogaster.

The invention provides a method for the detection of the analeptic and psychostimulant properties of extract obtained from Acorus calamus, using Drosophila melanogaster. Using a fruit fly model, more than 20 plant species were tested for neuroactive agents. The scientists found that the extracts of the plant Acorus calamus decreased the time taken by flies to recover from anesthesia, a state of severe CNS depression, produced by diethyl ether.

Further experiments carried out by them with one of the Acorus calamus extracts showed a similar effect on flies anesthetized with chloroform. Also, the extract suppressed delay in recovery from ether anesthesia caused by CNS depressant drug phenobarbital. In addition, the inhibition in flies' spontaneous locomotor activity caused by ethanol, an another CNS depressant, was also suppressed. Based on the above results they succeeded in demonstrating that the natural substance screened has a property akin to known analeptics, drugs and antagonize the action of CNS depressants.

The patent description stated that the plant extract was also found to increase spontaneous locomotor activity, an expression of CNS activity status, in normal flies. This is known to be an indication that the agent also possesses a property similar to known psychostimulants. Thus, the invention provides a substance from Acorus calamus plant with analeptic and psychostimulant properties which comprises use of a Drosophila model for in vivo drug screening, testing of a large number of plant extracts from various plant species and finding in the plant Acorus calamus a substance with analeptic and psychostimulant properties.