adult albino rats of wistar strain ( 150200 g ) of either sex were procured from government veterinary college , bangalore , and were housed in the animal house of kles college of pharmacy , ankola , with 12 h light and 12 h dark cycles . standard pellets obtained from goldmohar rat feed , mumbai , were used as a basal diet during the experimental period . the control and experimental animals were provided food and drinking water ad libitum . ltd , mumbai ) , glibenclamide ( aventis pharma ltd , verna , goa ) , dextrose ( emkay labs , mumbai ) , tween 80 ( s.d . fine - chem ltd , mumbai ) , and anesthetic ether ( ozone international , mumbai ) . accu - chek active glucometer ( roche diagnostic corporation , mannheim , germany ) , blood and glucostrips ( roche diagnostic pvt ltd , mumbai ) were used .all other chemicals and reagents used were of analytical grade . stem bark of c. nurvala was collected in and around the local forest area of sirsi in western ghats , karnataka , and authenticated by the botanist prof g. s. naik , department of botany , g. c. science and art college , ankola . a voucher herbarium specimen no . the collected bark was dried under shade and powdered to a coarse consistency in grinder mill . the powder was passed through 40 # mesh particle size and stored in an airtight container at room temperature . exactly 2.5 kg of the fresh air - dried , powered crude drug of c. nurvala was extracted with petroleum ether ( 6080c ) , chloroform , 95% ethanol , and chloroform water i. p. by adopting simple maceration procedure at room temperature for 7 days in a conical flask with occasional shaking and stirring . the extract was filtered and concentrated to dryness at room temperature to avoid the decomposition of the natural metabolites . the yield of the extracts was 1.46 , 3.62 , 10.65 , and 20.45% w / w for petroleum ether , chloroform , ethanol , and water , respectively . preliminary phytochemical analysis was carried out in all the four extracts by different methods of phytochemical analysis . a known volume of extract was suspended in distilled water and was orally administered to the animals by gastric intubation using a force feeding needle , during the experimental period . acute oral toxicity studies of the extracts were carried out as per the oecd guidelines , draft guidelines 423 adopted on 17 december , 2001 , received from committee for the purpose of supervision and control of experiments on animals ( cpcsea ) , ministry of social justice and empowerment , govt . of india . administration of the stepwise doses of all four extracts of c. nurvala from 50 mg / kg b. wt . up to the dose 5000 mg / kg b. wt . caused no considerable signs of toxicity in the tested animals . one tenth of upper limit dose were selected as the level for examination of antidiabetic activity . group i served as normal control ( nc ) and received distilled water with tween 80 . groups ii received standard drug glibenclamide as an aqueous suspension at a dose of 600 g / kg b. wt . groups iii  vi received different extracts at a dose of 500 g / kg b. wt . as a fine tween 80 suspension . after 30 min of extract administration , the rats of all groups were orally treated with 2 g / kg of glucose . blood samples were collected from the rat tail vein just prior to glucose administration and at 30 , 60 , and 90 min after glucose loading . alloxan monohydrate was first weighed individually for each animal according to their weight and then solubilized with 0.2 ml saline just prior to injection . diabetes was induced by injecting it at a dose of 150 mg / kg b. wt . intraperitonially . after 1 h of alloxan administration , the animals were given feed ad libitum , and 5% dextrose solution was also given in a feeding bottle for a day to overcome the early hypoglycemic phase . the animals were kept under observation and after 48 h blood glucose was measured by glucometer . the diabetic rats ( glucose level > 300 mg / dl ) were separated and divided into six different groups for experimental study , with each group containing six animals . the animals were divided into seven groups and each group consisted of six rats [ table 1 ] . different groups of experimental animals ( n=6 ) this experimental design was followed in both alloxan - induced model and in oggt model , but in the latter model normal rats loaded with glucose were used instead of diabetic rats . body weight was measured totally four times during the course of study period [ i.e. , before alloxan induction ( initial values ) , and on the first , fourth , and seventh days of the treatment period ] , using a digital weighing scale obtained from kern ( emb ) , tischwaage , germany . the results of the study were subjected to one way analysis of variance ( anova ) followed by dunnett 's t test for multiple comparisons . values with p < 0.05 were considered significant . adult albino rats of wistar strain ( 150200 g ) of either sex were procured from government veterinary college , bangalore , and were housed in the animal house of kles college of pharmacy , ankola , with 12 h light and 12 h dark cycles . standard pellets obtained from goldmohar rat feed , mumbai , were used as a basal diet during the experimental period . the control and experimental animals were provided food and drinking water ad libitum . ltd , mumbai ) , glibenclamide ( aventis pharma ltd , verna , goa ) , dextrose ( emkay labs , mumbai ) , tween 80 ( s.d . fine - chem ltd , mumbai ) , and anesthetic ether ( ozone international , mumbai ) . accu - chek active glucometer ( roche diagnostic corporation , mannheim , germany ) , blood and glucostrips ( roche diagnostic pvt ltd , mumbai ) were used .all other chemicals and reagents used were of analytical grade . stem bark of c. nurvala was collected in and around the local forest area of sirsi in western ghats , karnataka , and authenticated by the botanist prof g. s. naik , department of botany , g. c. science and art college , ankola . a voucher herbarium specimen no . the collected bark was dried under shade and powdered to a coarse consistency in grinder mill . the powder was passed through 40 # mesh particle size and stored in an airtight container at room temperature . exactly 2.5 kg of the fresh air - dried , powered crude drug of c. nurvala was extracted with petroleum ether ( 6080c ) , chloroform , 95% ethanol , and chloroform water i. p. by adopting simple maceration procedure at room temperature for 7 days in a conical flask with occasional shaking and stirring . the extract was filtered and concentrated to dryness at room temperature to avoid the decomposition of the natural metabolites . the yield of the extracts was 1.46 , 3.62 , 10.65 , and 20.45% w / w for petroleum ether , chloroform , ethanol , and water , respectively . preliminary phytochemical analysis was carried out in all the four extracts by different methods of phytochemical analysis . a known volume of extract was suspended in distilled water and was orally administered to the animals by gastric intubation using a force feeding needle , during the experimental period . acute oral toxicity studies of the extracts were carried out as per the oecd guidelines , draft guidelines 423 adopted on 17 december , 2001 , received from committee for the purpose of supervision and control of experiments on animals ( cpcsea ) , ministry of social justice and empowerment , govt . of india . administration of the stepwise doses of all four extracts of c. nurvala from 50 mg / kg b. wt . up to the dose 5000 mg / kg b. wt . caused no considerable signs of toxicity in the tested animals . one tenth of upper limit dose were selected as the level for examination of antidiabetic activity . group i served as normal control ( nc ) and received distilled water with tween 80 . groups ii received standard drug glibenclamide as an aqueous suspension at a dose of 600 g / kg b. wt . groups iii  vi received different extracts at a dose of 500 g / kg b. wt . as a fine tween 80 suspension . after 30 min of extract administration , the rats of all groups were orally treated with 2 g / kg of glucose . blood samples were collected from the rat tail vein just prior to glucose administration and at 30 , 60 , and 90 min after glucose loading . alloxan monohydrate was first weighed individually for each animal according to their weight and then solubilized with 0.2 ml saline just prior to injection . diabetes was induced by injecting it at a dose of 150 mg / kg b. wt . intraperitonially . after 1 h of alloxan administration , the animals were given feed ad libitum , and 5% dextrose solution was also given in a feeding bottle for a day to overcome the early hypoglycemic phase . the animals were kept under observation and after 48 h blood glucose was measured by glucometer . the diabetic rats ( glucose level > 300 mg / dl ) were separated and divided into six different groups for experimental study , with each group containing six animals . group i served as normal control ( nc ) and received distilled water with tween 80 . groups ii received standard drug glibenclamide as an aqueous suspension at a dose of 600 g / kg b. wt . groups iii  vi received different extracts at a dose of 500 g / kg b. wt . as a fine tween 80 suspension . after 30 min of extract administration , the rats of all groups were orally treated with 2 g / kg of glucose . blood samples were collected from the rat tail vein just prior to glucose administration and at 30 , 60 , and 90 min after glucose loading . alloxan monohydrate was first weighed individually for each animal according to their weight and then solubilized with 0.2 ml saline just prior to injection . diabetes was induced by injecting it at a dose of 150 mg / kg b. wt . intraperitonially . after 1 h of alloxan administration , the animals were given feed ad libitum , and 5% dextrose solution was also given in a feeding bottle for a day to overcome the early hypoglycemic phase . the animals were kept under observation and after 48 h blood glucose was measured by glucometer . the diabetic rats ( glucose level > 300 mg / dl ) were separated and divided into six different groups for experimental study , with each group containing six animals . the animals were divided into seven groups and each group consisted of six rats [ table 1 ] . different groups of experimental animals ( n=6 ) this experimental design was followed in both alloxan - induced model and in oggt model , but in the latter model normal rats loaded with glucose were used instead of diabetic rats . body weight was measured totally four times during the course of study period [ i.e. , before alloxan induction ( initial values ) , and on the first , fourth , and seventh days of the treatment period ] , using a digital weighing scale obtained from kern ( emb ) , tischwaage , germany . the results of the study were subjected to one way analysis of variance ( anova ) followed by dunnett 's t test for multiple comparisons . values with p < 0.05 were considered significant . standardization parameters for c. nurvala stem bark were determined and all the parameters were found to be within pharmacopoeial standards limit . crude powder taken for extraction was of yellowish - brown color with a bitter taste . loss on drying , total ash , acid insoluble ash , and water soluble ash were found to be 4.37 , 9.76 , 0.647 , and 1.56% w / w , respectively . thin layer chromatography of c. nurvala stem bark revealed bright brownish red spot ( rf= 0.30 ) , rf= 0.71 ( magenta color ) , rf= 0.15 , 0.90 ( light violet spots ) which turn magenta on keeping . phytochemical screening of all the extract of c. nurvala showed the presence of various chemical constituents , mainly triterpenoids and flavonoids which may be responsible for its antilithic and antidiabetic properties , respectively . , all the extracts of c. nurvala stem bark did not show significant toxicity signs when observed for the parameters during the first 4 h and followed by daily observations for 14 days and no mortality was also observed ; the drug was found to be safe at the tested dose level of 5000 mg / kg b. wt . to ascertain a scientific base for the usefulness of this plant in the treatment of diabetes , it was decided to evaluate experimental design of antidiabetic activity by following glucose tolerance test and the alloxan - induced model . as expected , in the diabetic control ( dc ) compared with the dc , all the four extracts , c. nurvala aqueous extract ( cnae ) , c. nurvala ethanolic extract ( cnee ) , c. nurvala chloroform extract ( cnce ) , and c. nurvala petroleum ether extract ( cnpee ) [ table 1 ] , lowered the elevated blood glucose levels only in subacute treatment [ table 2 ] . it was observed that the standard drug glibenclamide lowered the blood glucose level significantly bringing it nearly back to normal , whereas cnpee and cnee significantly ( p < 0.01 ) decreased fasting blood serum glucose in the diabetic rats on third , fifth , and seventh days compared with the initial ( 0 h ) blood serum glucose levels [ figure 1 ] . effect of c. nurvala extracts on blood glucose level of alloxan - induced diabetic albino rats after subacute treatment blood glucose level of alloxan - induced diabetic albino rats after treatment the effects of different extracts on glucose tolerance test in normal rats are shown in table 3 . at 30 min after glucose administration , the peak of blood glucose level increased rapidly from the fasting value and then subsequently decreased . effect of c. nurvala extracts on ogtt in normal rats in the present study , diabetic rats had lower body weights , high blood glucose level as compared to the normal rats . in spite of the increased food consumption , loss of body weight due to defect in glucose metabolism and excessive breakdown of tissue protein is a characteristic condition in diabetics . as shown in table 4 , treatment with cnee and cnpee improved the average body weights of rats which indicate control over polyphagia and muscle wasting resulted due to hyperglycemic condition . effect of various extracts on body weight after treatment in diabetic rats alloxan causes massive reduction in insulin release , through the destruction of -cells of the islets of langerhans . in our study , we have observed a significant increase in the plasma insulin level when alloxan diabetic rats were treated with cnae and cnpee . this could be due to potentiation of the insulin effect of plasma by increasing the pancreatic secretion of insulin from existing -cells of islets of langerhans or its release from bound insulin . the significant and consistent antidiabetic effect of cnee and cnpee in alloxan diabetic rats may also be due to enhanced glucose utilization by peripheral tissues . few researchers such as alam et al . have reported the antinociceptive effect of the crude ethanolic extract of c. nurvala on mice and showed that its action was peripherally and centrally mediated . bhaskar et al . have reported the antifertility activity of stem bark of c. nurvala and that their action was due to antizygotic and blasocytotoxicity . neither the exact biological active constitutent(s ) responsible for the above said effect nor the exact mode of action of the antidiabetic activity was reported earlier , with the lone observation that it is used in folklore diabetic treatments . we conclude that the cnee and cnpee have potent antidiabetic effects in alloxan - induced diabetic rats . the present investigation has also opened avenues for further research especially with reference to the development of potent formulation for diabetes mellitus from c. nurvala stem bark . activity guided fractionation , formulation , and its evaluation is in progress and will be available in short period of time .
objectives : the aim of this study was to investigate the antidiabetic activity of crateva nurvala stem bark ( family : capparidaceae ) extracts in alloxan - induced diabetic albino rats . 
 a comparison was made between the action of different extracts of c. nurvala and a known antidiabetic drug glibenclamide ( 600 g / kg b. wt . ) . 
 an oral glucose tolerance test ( ogtt ) was also performed in diabetic rats.materials and methods : the petroleum ether , chloroform , alcohol , and aqueous extracts of c. nurvala stem bark were obtained by simple maceration method and were subjected to standardization by following pharmacognostical and phytochemical screening methods . 
 dose selection was made on the basis of acute oral toxicity study ( 505000 mg / kg b. wt . ) as per organization for economic co - operation and development ( oecd ) guidelines.results and conclusions : c . 
 nurvala petroleum ether extract ( cnpee ) and ethanolic extract ( cnee ) showed significant ( p < 0.001 ) antidiabetic activities . in alloxan - induced model , blood glucose level of these extracts on seventh day of study were cnpee ( 126.3313.703 mg / dl ) and cnee ( 126.6613.012 mg / dl ) when compared with diabetic control ( 413.504.752 mg / dl ) and chloroform extract ( 320.8313.516 mg / dl ) . in oggt model ( glucose loaded rats ) , 
 cnpee showed a glucose level of 178.833.070 mg / dl after 30 min and 131.662.486 mg / dl after 90 min , whereas cnee showed 173.664.224 mg / dl after 30 min and 115.503.394 mg / dl after 90 min . 
 these extracts also prevented body weight loss in diabetic rats . 
 the drug has the potential to act as an antidiabetic drug .