|Year : 2013 | Volume
| Issue : 4 | Page : 270-276
Mitigation of starch-induced postprandial glycemic spikes in rats by antioxidants-rich extract of Cicer arietinum Linn. seeds and sprouts
Ashok Kumar Tiwari1, Chinthapatla Sahana1, Amtul Zehra1, Kuncha Madhusudana1, Domati Anand Kumar1, Sachin Bharat Agawane2
1 Medicinal Chemistry and Pharmacology Division, Council of Scientific and Industrial Research-Indian Institute of Chemical Technology, Hyderabad, Andhra Pradesh, India
2 Medicinal Chemistry and Pharmacology Division, Council of Scientific and Industrial Research-Indian Institute of Chemical Technology, Hyderabad, Andhra Pradesh; Biochemical Sciences Division, Council of Scientific and Industrial Research-National Chemical Laboratory, Pune, Maharashtra, India
|Date of Submission||18-Jan-2013|
|Date of Decision||10-Jul-2013|
|Date of Acceptance||05-Aug-2013|
|Date of Web Publication||19-Oct-2013|
Ashok Kumar Tiwari
Medicinal Chemistry and Pharmacology Division, Council of Scientific and Industrial Research-Indian Institute of Chemical Technology, Hyderabad, Andhra Pradesh
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Introduction: Consumption of highly processed calories dense diet leads abrupt increase in postprandial blood glucose level, which in turn induces immediate oxidative stress. Postprandial hyperglycemia (PPHG) and resultant oxidative stress is one of the earliest detectable abnormalities in diabetes prone individuals, independent risk factor for development of cardiovascular disorders (CVD), a major pathophysiological link between diabetes and CVD and an important contributing factor in atherogenesis even in non-diabetic individuals. Therefore, dietary supplements mitigating PPHG spikes along with potent antioxidant activities may help decrease development of PPHG and oxidative stress induced pathogenesis. Objectives: The study evaluated free radicals scavenging, antioxidant properties and intestinal α-glucosidase inhibitory activity in methanol extract of two varieties of Cicer arietinum Linn viz. Bengal gram and Kabuli chana and green gram (Vigna radiata Linn. Wilczek) raw grains and their sprouts and studied their influence on starch-induced postprandial glycemic excursion in rats. Materials and Methods: Healthy grains were procured from local markets. Free radicals scavenging antioxidant and glucose-induced hemoglobin (Hb)-glycation inhibition activities were analyzed using standard in vitro procedures. In vitro antihyperglycemic activity was evaluated by assessing rat intestinal α-glucosidase inhibitory activity. Influence on starch-induced postprandial glycemic excursion in rats was studied by pre-treatment of rats with extracts. Results: Compared with raw seeds increase in total polyphenol and flavonoids concentration in green gram sprouts and Kabuli chana sprouts (KCs) were observed. Total protein concentrations in sprouts did not differ from non-sprouted grains. 2,2'- Azinobis (3-ethyl benzthiazoline-6-sulphonic acid) cation scavenging activity was more than twice in Bengal gram sprouts of (BGs) and KCs than their raw seeds. 2,2-diphenyl-1-picrylhydrazyl, hydrogen peroxide scavenging, nitro blue tetrazolium reducing and glucose-induced Hb-glycation inhibitory activity did not differ from non-sprouted raw grains. Increase in rat intestinal α-glucosidase inhibitory activity was observed in BGs and KCs. BGs significantly mitigated 1 st 30 min starch-induced postprandial glycemic excursions and reduced 2 h postprandial glycemic load. Conclusion: Sprouting leads dynamic changes in free radicals scavenging potentials and antioxidant activities in grains. Consumption of seeds as well as BGs before the starch-rich meal can significantly mitigate 1 st 30 min postprandial glycemic excursion and reduce 2 h postprandial glycemic burden.
Keywords: Antioxidant activity, Bengal gram sprouts, oxidative stress, postprandial glycemic excursion, postprandial hyperglycemia
|How to cite this article:|
Tiwari AK, Sahana C, Zehra A, Madhusudana K, Kumar DA, Agawane SB. Mitigation of starch-induced postprandial glycemic spikes in rats by antioxidants-rich extract of Cicer arietinum Linn. seeds and sprouts. J Pharm Bioall Sci 2013;5:270-6
|How to cite this URL:|
Tiwari AK, Sahana C, Zehra A, Madhusudana K, Kumar DA, Agawane SB. Mitigation of starch-induced postprandial glycemic spikes in rats by antioxidants-rich extract of Cicer arietinum Linn. seeds and sprouts. J Pharm Bioall Sci [serial online] 2013 [cited 2020 Feb 24];5:270-6. Available from: http://www.jpbsonline.org/text.asp?2013/5/4/270/120077
Traditionally, selection of particular diets, food practices and patterns by population around the world was influenced by a number of factors such as local climatic conditions, ethnobotanical and cultural practices, prevalence of local food items and richness of bioactive compounds generated during the course of adaptation to local stressful environmental conditions.  Therefore, our genome has mostly been optimized for such food environment  and our ability to metabolize a food item has genetically been adapted  for such dietary signatures we were evolved with.  However, in modern globalized world, food and activity choices are being shaped differently. In fact, during the course of modernization, globalization and following the advent of various scientific terms such as functional foods, nutraceuticals, food additives etc., the texture and matrix of traditional dietary practice has changed and influenced the nutritive as well as medicinal values of food preparations.  Increased consumption of highly processed, calorie-dense and nutrient-depleted foods is being observed to exaggerate spikes in blood glucose and lipid. This state, also referred to as postprandial dysmetabolism, induces immediate oxidative stress, which is directly proportional to the elevations in blood glucose and triglycerides levels after a meal.  These changes are thought to be important contributors for the outbreak of a number of life-style related metabolic disorders such as hyperglycemia and hyperlipidemia.  It becomes important therefore, to identify food items and practices that impart benefits and assort those adversely affecting our health.
Seeds of Cicer arietinum Linn (Chickpea) are one of the ancient and widely consumed legumes in tropical and subtropical countries.  Two main varieties of C. arietinum seeds viz. Kabuli chana (KC) (cream seed-coat) and Bengal gram (BG) (brown seed-coat) constitute important human and domestic animal's foods in South Asia. Chickpea is well-studied for its physicochemical composition and nutritional values and is a cheap source of high quality dietary protein, low digestible starch, minerals and trace elements. ,,, Seeds of KC are larger in size than BG and are preferred over BG in terms of cooking time and sensory properties; however, calcium content in BG is reported to be higher than KC.  De-hulled cotyledons of BG are used as pulses and flour (Besan) for preparation of different snacks. Parched seeds (Batana) and parched seed-flour (Sattoo) are a popular snack items. Germinated BG and KC seeds serve important entry point in modern buffet-menu.
In traditional Indian medicines, BG seeds have been advocated as tonic, stimulant and aphrodisiac.  Soup of BG has been prescribed beneficial in condition of excessive burning sensation in fever, parched BG flour in colic and soaked seeds as purgative.  Furthermore, BG seeds are also used in bronchitis, leprosy, skin and blood disorders and biliousness.  However, despite the extensive use of chickpeas as food material in tropical countries, application in traditional medicines and investigation on nutritional values, least effort has been made to scientifically evaluate its beneficial effect on life-style-induced metabolic disorders.
The sprouts of Bengal gram, Kabuli chana, and green gram (BGs, KCs, and GGs) get entry point place in the modern buffet-menu, which follows a number of energy-rich, calorie-dense food items. For, the order of food items arrangement on a buffet-table is an important consideration, the aim of this study was to examine whether pre-consumption of BGs, KCs and GGs affect metabolism of carbohydrates and have any influence on postprandial glycemic level following starch-rich diet. In this report, we present analysis of chemical components and antioxidant activities in methanol extract of raw seeds of BG, KC and GG and their sprouts and evaluate the effect of methanol extract on starch-induced postprandial glycemic excursion in rats.
| Materials and Methods|| |
Chemicals used in this study were of high purity grade and purchased from Sigma-Aldrich chemicals (St. Louis, MO USA), Merck (India) Limited (Mumbai, India) and S.D. Fine Chemicals Ltd (Mumbai, India).
Seed germination and preparation of extracts
BG, KC (C. arietinum Linn.) and GG (Vigna radiata Linn. Wilczek) grains were purchased from local markets of Hyderabad city (India). Healthy grains were selected and washed with clean water. A cotton bed was prepared to spread and germinate grains. A total of 500 g of grains was spread on the wet-cotton bed at room temperature with ample light and air. Grains were covered with similar type of cotton covering. Water was sprinkled as and when required to keep bedding wet. Sprouts with 1.5-3.0 cm germinate length were picked up for analysis. It took about 72 h for grains to germinate up to this length. Fine powder of raw clean grains and their sprouts were prepared for extraction. Powders were soaked in 85% methanol for 3 days at room temperature. Supernatant was vacuum filtered, concentrated to 1/3 volume under reduced pressure in rotary evaporator (50 1C) and lyophilized to dry. Extracts were refrigerated until analysis.
Analysis of chemical components in raw and sprout of seeds
Total polyphenolic content
Total phenolic content in extracts was measured using Folin-Ciocalteu reagent.  Briefly, 25 μL of extract (10 mg/mL in dimethyl sulfoxide [DMSO] was diluted with 2.5 mL of distilled de-ionized water followed by the addition of 250 μL of Folin-Ciocalteu reagent (1 M) and 250 μL of Na 2 CO 3 (20% w/v). The mixture was incubated at room temperature for 60 min and absorbance was measured spectrophotometrically at 765 nm. Results were expressed in terms of milligrams gallic acid equivalent.
Presence of anthocyanins in extract (10 mg/mL in DMSO) was determined applying method described earlier.  To 25 mM potassium chloride solution (pH 1.0) and 0.4 M sodium acetate buffer (pH 4.5), equal volumes of extract was added and absorbance was measured at 510 nm and 700 nm. Data was expressed using molecular extinction coefficient, molecular weight of anthocyanins and an absorbance of A = ([A 510 -A 700 ] pH 1.0− [A 510 -A 700 ] pH 4.5) as milligrams of anthocyanins per 100 g of extract.
Total flavonoids content in extract (10 mg/mL in DMSO) was measured by mixing equal volume of extract with 2% AlCl 3·6H 2 O in a 96 well plate.  Absorbance was recorded spectrophotometrically at 430 nm. Results were expressed as milligrams of rutin equivalent.
Total protein content
Total protein content in extract (10 mg/mL in DMSO) was determined using the Bradford's reagent.  Briefly, 10 μL of extract was mixed with 240 μL of Bradford reagent and absorbance was read at 595 nm spectrophometrically. Protein concentration (mg/mL) was expressed applying a Bovine serum albumin regression curve.
Determination of free radicals scavenging antioxidant potentials and enzyme inhibitory activity
2,2'-Azinobis (3-ethyl benzthiazoline-6-sulphonic acid) (ABTS + ) cation scavenging
End point decolorization of cation ABTS + was measured.  Determination of ABTS + scavenging concentration 50% (SC 50 ) extract was performed with several serial dilutions of extract. Percentage scavenging of ABTS + extract was calculated by applying formula: ([absorbance control − absorbance test]/Absorbance control) ×100. Results were expressed in terms of ascorbic acid equivalent concentration (mg/mL). The SC 50 values were calculated applying suitable regression analysis.
2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging
Scavenging of DPPH radical was determined as reported earlier.  Briefly, in a 96-well microplate reaction mixture was prepared with 25 μL extract (5 mg/mL DMSO), 100 μL of 0.1 M Tris-HCl buffer (pH 7.4), 125 μL DPPH solutions (0.5 mM in methanol) and incubate in dark for 30 min. DPPH decolonization was recorded at 517 nm. Percentage DPPH scavenging and SC 50 values were calculated as above.
Hydrogen peroxide (H 2 O 2 ) scavenging
Determination of H 2 O 2 scavenging activity,  was performed as follows: 40 μL of extract (5 mg/mL DMSO) was mixed with 1.2 mL of H 2 O 2 solution (21.5 mM H 2 O 2 in phosphate buffer). Absorbance of the reaction mixture was recorded at 0 min up to 30 min at 230 nm. For each test sample, a separate blank (devoid of H 2 O 2 ) was used for background subtraction. Percentage of H 2 O 2 scavenging was calculated applying the following formula: ([Absorbance control − Absorbance test]/Absorbance control) ×100.
Reduction of nitro blue tetrazolium (NBT)
NBT reducing activity as a measure of the presence of ascorbic acid,  in extract (5 mg/mL DMSO) was determined following method reported earlier.  Briefly, in a 96-well plate containing 100 μL phosphate buffer (50 mM, pH 10) and an equal volume of NBT (1 mM, prepared in the same buffer), 50 μL of extract was mixed and incubated for 15 min. A blank with extract in the absence of NBT was run to correct background absorbance. The reduction of NBT was measured at 560 nm using a BioTek synergy4 multimode microplate reader (BioTek Instruments Inc., Winooski, VT, USA). The percentage of NBT reduction by extract was obtained in terms of ascorbic acid equivalent.
Prevention of glucose induced hemoglobin (Hb)-glycation
This method was adopted from Asgary et al.  with slight modifications. Blood was collected from adult male Wistar rats in tubes containing anticoagulant ethylenediaminetetraacetic acid (EDTA) and centrifuged at 1000 rpm for 20 min. Pellet was suspended with phosphate-buffered saline (PBS) (pH 7.4). Red blood cells were lysed with 2 volumes of lysis buffer. Centrifugation was carried out to remove debris and supernatant containing hemoglobin was collected and diluted with PBS so as to get 5 g/dL concentration. A total of 0.5 mL of the above solution was transferred to eppendorf tube and incubated with 200 μL extract (10 mg/mL DMSO) for 10 min. 500 μL solution containing glucose (2 g/100 mL) and gentamycin (20 mg/mL) was added and again incubated for 72 h. Amount of glycated hemoglobin in the reaction mixture was calculated by measuring absorbance at 443 nm.
Intestinal α-glucosidase inhibition
Inhibition of rat intestinal α-glucosidase enzyme was determined as reported earlier.  20 μL of extract (10 mg/mL DMSO) was incubated with 50 μL of crude intestinal α-glucosidase for 5 min and then with 50 μL of substrate 5 mM p-nitrophenyl-α-D- glucopyranoside. Absorbance was measured at 405 nm. Percent enzyme inhibition was calculated applying formula mentioned above and expressed in terms of acarbose (Acb) equivalent concentration (mg/mL solution).
Animal experiments were performed using male adult Wistar rats (180-220 g body weight). Institutional Animal Ethical Committee (CPCSEA Reg. No. 97/1999, Government of India) approval for the experimental protocol was obtained. All experiments with live animals were performed in compliance with the relevant laws and institutional guidelines. Experiments were performed as reported earlier.  All animals were kept for overnight fasting. The next day forenoon blood was collected from the retro orbital plexus in EDTA containing tubes. Plasma glucose levels for the basal ("0" h) value were measured by glucose-oxidase test method using auto-blood analyzer instrument (Bayer Express Plus, NY, USA). Rats were divided into various groups (five rats in each group) as follows:
Methanol extract of samples were suspended in normal saline and administered to the respective group of animals at a random dose of 250 mg/kg (p.o.) body weight. Control group of animals were administered normal saline. After 15 min of normal saline or extract administration, animals were fed with soluble-starch dissolved in normal saline at a dose of 2 g/kg body weight. Thereafter, blood samples were collected at intervals of 30, 60, 90 and 120 th min post-starch feeding. Plasma was separated out for glucose measurement as described above. At 2 h, postprandial glycemic load (AUC 0-120 min mg/dL) was calculated following trapezoidal rules.
- Control (normal saline followed by starch)
- BG (BG extract followed by starch)
- BGs (BGs extract followed by starch)
- GG (GG extract followed by starch)
- GGs (GGs extract followed by starch)
- Control (normal saline followed by starch)
- KC (KC extract followed by starch)
- KCs (KCs extract followed by starch)
- Acb (Acb followed by starch).
One-way analysis of variance followed by Dunnett's multiple comparison tests was applied to compare the difference in animal study groups. Suitable regression analysis was applied to find correlations between the related parameters. The criterion for statistical significance was P < 0.05. Statistical analyses were performed by using GraphPad PRISM® Version 5.01 (GraphPad software, Inc., California, USA).
| Results|| |
The analysis of chemical components primarily responsible for free radicals scavenging, antioxidant and enzyme inhibitory activities are presented in [Table 1]. Although the yield of methanol extract did not differ in BGs and GGs from their raw grains, it was 45% more in KCs than KC raw grain. Germination (sprouting) led 30% increase in total polyphenolic content in GGs and 74% in KCs when compared with the concentration of their raw grains. Similarly, total flavonoids content increased to 30% in GGs and doubled in KCs due to sprouting. However, 13% decrease in total protein content was observed in BGs and KCs when compared with the protein content of their raw grains. Anthocyanins could not be detected in any extract.
|Table 1: Analysis of chemical components, free radicals scavenging, anti-glycation and enzyme inhibitory activities in seed grains and sprouts|
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Based on SC 50 values, it was found that sprouting resulted in two folds increase in ABTS + radical scavenging potential in BGs and KCs when compared with BG and KC. However, it was found unchanged in GG and GG S . On the other hand, DPPH free radical scavenging potential was found decreased in BGs and increased in GGs when compared with BG and GG respectively [Table 1].
BG, BGs, GG and GGs displayed similar NBT reducing activity. However, NBT reducing activity of KCs was more than KC [Table 1]. All the extracts displayed similar H 2 O 2 scavenging activity. In KCs 9% decrease in hemoglobin (Hb)-glycation activity was found when compared with KC, no apparent change was noticed in BG, BGs, GG and GGs Hb-glycation activity [Table 1]. BGs displayed 8% and KCs 7% more rat intestinal α-glucosidase enzyme inhibitory activity than BG and KC extracts respectively [Table 1].
An inverse relationship between the starch-induced postprandial glycemic excursions was observed with fasting plasma glucose level of rats [Figure 1]a and b. However, the 2 h postprandial glycemic load was found positively correlated with fasting plasma glucose values [Figure 1]c. [Figure 2]a and d present shape of plasma glucose concentration curve of rats following oral starch-tolerance test under the influence of extracts. The plasma glucose level of rats pre-treated with KC following starch administration was found more than control after 60 th min [Figure 2]d. Starch-induced spikes in plasma glucose level of rats pre-treated with BG and BGs was significantly lesser than the control group of rats at 30 th min [Figure 2]b. Although, the starch-induced glycemic spikes at the 30 th min were recorded less in KC (52%) and KCs (32%) treated rats when compared with the control group [Figure 2]d and e, data in our study could not reach statistical significance. At 2 h starch-induced postprandial glycemic load in rats pre-treated with chickpea raw seeds and their sprouts were 2-6% lesser than the control group of rats [Figure 2]c and f. The starch-induced glycemic load was significantly less in rats pre-treated with standard intestinal α-glucosidase enzyme inhibitory drug Acb [Figure 2]f. Pre-treatment of rats with GG or GGs methanolic extract could not affect starch-induced postprandial glycemia in our study.
|Figure 1: Association between fasting plasma glucose level and ΔG30th min mg/dL, ΔG120th min mg/dL in starch-induced postprandial glycemic spikes. ΔG represents the difference in plasma glucose level between fasting and 30th min. (a) And 120th min. (b) Post-starch administration to rats. It represents measure of post-starch feeding glycemic spikes. (c) Association between fasting plasma glucose and 2 h postprandial glycemic load (Area Under the Curve, AUC0-120 min mg/dL) induced by starch administration in rats. Pearson correlation represents normally distribution in variable while Spearman correlation represents a non-parametric distribution in variables. Values plotted in this figure represent plasma glucose level of the control group of rats|
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|Figure 2: The shape of plasma glucose concentration curves (a and d) following starch administration to overnight fasted rats with or without pre-treatment of study materials. Figures b and e represent ΔG. ΔG is the difference in plasma glucose level between fasting and 30th post-starch administration to rats. Figures c and f presents 2 h postprandial glycemic load (AUC0-120 min mg/dL) following starch administration. One-way analysis of variance followed by Dunnett's multiple comparison tests was applied to compare the difference in an animal study groups. The criterion for statistical significance was *P < 0.05. BG: Bengal gram, BGs: Bengal gram sprouts, KC: Kabuli chana, KCs: Kabuli chana sprouts, GG: Green gram, GGs: Green gram sprouts, Acb: acarbose. Values represent mean ± standard error, n = 5|
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| Discussion|| |
Consumption of germinated seeds has been one of the oldest practices of food processing as it increases nutritive value to the food.  In fact, during the process of germination, several latent metabolic processes are reactivated. It has been reported that insulin plays a key role in promoting germination process of seeds  and insulin-like proteins are synthesized only during the process of germination of seeds. Since, insulin secretion and action is compromised in diabetic patients, sprouts may be a good source of insulin-like proteins. 
Our study observed dynamic changes in total polyphenols, flavonoids, protein content and also in free radicals scavenging antioxidant properties in sprouted seeds when compared with respective raw seeds. Such changes have been reported in other studies also. , In fact, the antioxidant defense in body is a complicated process synergistically governed by non-enzymatic and enzymatic antioxidants. Changes in the phytochemical contents, free radicals scavenging potentials and antioxidant activities in sprouted seeds might be the natural balancing and/or adaptive mechanisms meant to support number of physiological activities and counter balance oxidative burden during germination process.  Our study finds differences in various free radicals scavenging potentials and antioxidant activities with different test models. Therefore, it is important to mention that measurement of single free radical scavenging or the antioxidant activity of a natural compound or mixture of compounds may not reflect the optimum antioxidant activities of a study material.
Postprandial hyperglycemia (PPHG) is one of the earliest detectable defects in diabetes prone individuals.  It has also been identified as an independent risk factor for development of cardiovascular disorders (CVD) in diabetics.  Furthermore, PPHG is also recognized as an important contributing factor in atherogenesis,  increased generation of free radicals and overt oxidative stress induction even in non-diabetic individuals.  Therefore, targeting PPHG may prove to represent the, sine qua non, for the "return" of postprandial glucose values at a "non-deleterious threshold" for early stages of the disease and later in the progression of diabetes.  The overt generation of free radicals and consequent oxidative stress has recently been ascertained as a major pathophysiological link between diabetes and CVD.  The glucose fluctuations during the postprandial periods and more specifically at glucose swings time, has been recognized to exhibit more specific triggering effect on oxidative stress than chronic sustained hyperglycemia.  It is important to refer Slama et al.  who argue that postprandial glycemic excursion plays an important role in total hyperglycemia reflected by an increase in glycated hemoglobin and advocate Δ-postprandial glycemia (the difference between postprandial and preprandial blood glucose level at different time points) as a more useful tool than conventional examination of absolute postprandial rise in blood glucose level. Therefore, control of acute glucose surge in type 2 diabetes has emerged as a new therapeutic approach,  to minimize activation of oxidative stress induced by hyperglycemia and control of development of diabetic complications.
Glucose surge is more prominent at breakfast and dinner times and is inversely correlated with pre-prandial plasma glucose level.  Our observation that fasting plasma glucose level is inversely associated with the increase in postprandial plasma glucose surge finds support with this study. However, the 2 h glycemic load in our study was found positively associated with fasting plasma glucose levels. These observations disclose the fact that trigger of oxidative stress may be pointed more toward individuals with lower fasting plasma glucose level.
Although, PPHG is an independent risk factor for development of vascular complications in type 2 diabetes, the control of acute postprandial glycemic spikes and consequent triggering effect of acute glycemic excursions on oxidative stress needs integration into glycemic disorders.  These observations suggest that dietary supplements possessing both anti-hyperglycemic as well as potent antioxidant activities may become beneficial in minimizing postprandial glycemic surge and counterbalance adverse effects of glycemic surge induced oxidative stress.
Shape of plasma glucose concentration curve during oral glucose tolerance test (OGTT) has been recognized as an important measure to predict future risk of type 2 diabetes mellitus (T2DM) development. It has been demonstrated that in subjects with normal glucose tolerance and impaired fasting blood glucose, whose plasma glucose concentration does not return to baseline after 60 min following OGTT, possess significant higher risk of T2DM development.  Furthermore, shape of plasma glucose concentration curve has well been used to evaluate and identify dietary materials possessing anti-hyperglycemic activities. ,,, BG and its sprouts (BGs) in particular, displayed potent free radicals scavenging and antioxidant properties along with the capacity to significantly mitigate sudden increase in 1 st h postprandial plasma glucose levels. Furthermore, in contrast to KC and its sprouts, responsiveness of rats to BG and its sprouts was consistent. GG did not influence starch-induced glycemic activity in our study.
Diet made up of BG seeds and pulses has been reported to reduce postprandial glycemic load in experimental animals  and clinical studies.  BGs are soft and contain more antioxidant potential than raw seeds and are taken in small quantities before meal. Our study used 250 mg/kg body weight dose in rats to evaluate anti-hyperglycemic activity of sprouts and their raw seeds extract. When translated into human dose applying formula: Human dose (mg/kg) = (animal dose [mg/kg] × [animal km/human km]),  consumption of approximately 50 g of BGs by adult human prior to meal may reduce 1 st h postprandial plasma glucose surge, assuage postprandial plasma glucose-induced oxidative stress and reduce the burden of PPHG induced by consumption of starch-rich diet.
| Conclusion|| |
In conclusion, our study finds that sprouting leads increase in total polyphenols and flavonoids contents and dynamic changes in free radicals scavenging and antioxidant activities in BG, KC and GG seed. Only BG seeds and sprouts could significantly mitigate 1 st 30 min starch-induced postprandial glycemic excursion and reduce 2 h postprandial glycemic burden. The BGs therefore, may become sprouts of choice before consumption of starch-rich meals.
| Acknowledgments|| |
Authors thank Director, CSIR-IICT for constant encouragement and supports. This work was financially supported in part from CSIR-NewDelhi grant NaPAHA (CSC-0130). Authors also thankfully acknowledge reviewers for their constructive comments on this research.
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[Figure 1], [Figure 2]