Α-amylase Enzyme Inhibitory Activity Research Articles

Paris polyphylla Sm. extract enriched with diosgenin as an antidiabetic agent: In vitro and in vivo study

BackgroundThe global epidemic of diabetes mellitus (DM) has become a severe metabolic disorder and a threat to public health. Medicinal plants as a remedy for managing diabetes is accepted worldwide due to their long-term effectiveness and fewer side effects, mainly attributed to the phytochemicals. Paris polyphylla is a valuable medicinal herb endowed with steroidal saponins of therapeutic importance. The plant is popularly used as an anticancer agent. However, the antidiabetic potential of P. polyphylla has not been explored. So, the present study was undertaken to investigate the antidiabetic potential of P. polyphylla extract enriched with diosgenin (PPED) in vitro and in vivo in streptozotocin (STZ) induced diabetic rats. MethodP. polyphylla rhizomes were used to extract diosgenin-enriched extracts. The P. polyphylla extract enriched with diosgenin (PPED) was quantified using standard diosgenin in HPLC. The in vitro antidiabetic efficacy of PPED was determined by α-glucosidase and α-amylase enzyme inhibitory activity. PPED 1 (200 mg/kg b.w) and PPED 2 (400 mg/kg b.w) was administered in normal glycemic rats to evaluate the oral glucose tolerance test (OGTT). PPED 1 and PPED 2 were orally dosed for 28 days daily in STZ-induced diabetic rats, and the fasting blood glucose level and body weight were monitored every 7 days. Furthermore, the antioxidant, serum biochemical parameters, and pancreatic histopathology were studied. ResultsP. polyphylla extract enriched with diosgenin was quantified. PPED exhibited a concentration-dependent inhibition of α-amylase and α-glucosidase enzymes with IC50 275.7 ± 0.59 μg/mL and 121.9 ± 1.21 μg/mL. Daily oral dosage of PPED 1 and PPED 2 for 28 days leads to a significant decrease in fasting blood glucose level and recovery of body weight compared to the diabetic control. The liver and kidney antioxidant parameters also improved with PPED dosage. According to our study, the PPED 1 and PPED 2 treated groups showed a decrease in glycated hemoglobin (HbA1c) and hyperlipidemia, as well as an improvement in protein, liver, and kidney function parameters. Moreover, PPED administration also ameliorates the pancreatic islets' size and β-cell granularity compared to the diabetic control group. It is, therefore, possible to conclude that PPED has the potential as an antidiabetic agent. ConclusionThis is the first report of P. polyphylla extract enriched with diosgenin as a potent antidiabetic agent. The present study broadens the therapeutic horizon of P. polyphylla as an invaluable medicinal plant.

Ultrasonic-Assisted Synthesis of Heterocyclic Curcumin Analogs as Antidiabetic, Antibacterial, and Antioxidant Agents Combined with in vitro and in silico Studies.

Heterocyclic analogs of curcumin have a wide range of therapeutic potential and the ability to control the activity of a variety of metabolic enzymes. 1H-NMR and 13C-NMR spectroscopic techniques were used to determine the structures of synthesized compounds. The agar disc diffusion method and α-amylase inhibition assay were used to examine the antibacterial and anti-diabetic potential of the compounds against α-amylase enzyme inhibitory activity, respectively. DPPH-free radical scavenging and lipid peroxidation inhibition assays were used to assess the in vitro antioxidant potential. In this work, nine heterocyclic analogs derived from curcumin precursors under ultrasonic irradiation were synthesized in excellent yields (81.4-93.7%) with improved reaction time. Results of antibacterial activities revealed that compounds 8, and 11 displayed mean inhibition zone of 13.00±0.57, and 19.66±00 mm, respectively, compared to amoxicillin (12.87±1.41 mm) at 500 μg/mL against E. coli, while compounds 8, 11 and 16 displayed mean inhibition zone of 17.67±0.57, 14.33±0.57 and 23.33±00 mm, respectively, compared to amoxicillin (13.75±1.83 mm) at 500 μg/mL against P. aeruginosa. Compound 11 displayed a mean inhibition zone of 11.33±0.57 mm compared to amoxicillin (10.75±1.83 mm) at 500 μg/mL against S. aureus. Compound 11 displayed higher binding affinities of -7.5 and -8.3 Kcal/mol with penicillin-binding proteins (PBPs) and β-lactamases producing bacterial strains, compared to amoxicillin (-7.2 and -7.9 Kcal/mol, respectively), these results are in good agreement with the in vitro antibacterial activities. In vitro antidiabetic potential on α-amylase enzyme revealed that compounds 11 (IC50=7.59 µg/mL) and 16 (IC50=4.08 µg/mL) have higher inhibitory activities than acarbose (IC50=8.0 µg/mL). Compound 8 showed promising antioxidant inhibition efficacy of DPPH (IC50 = 2.44 g/mL) compared to ascorbic acid (IC50=1.24 g/mL), while compound 16 revealed 89.9±20.42% inhibition of peroxide generation showing its potential in reducing the development of lipid peroxides. In silico molecular docking analysis, results are in good agreement with in vitro biological activity. In silico ADMET profiles suggested the adequate oral drug-likeness potential of the compounds without adverse effects. According to our findings, both biological activities and in silico computational studies results demonstrated that compounds 8, 11, and 16 are promising α-amylase inhibitors and antibacterial agents against E. coli, P. aeruginosa, and S. aureus, whereas compound 8 was found to be a promising antioxidant agent.

Comparative antihyperglycemic, analgesic and anti-inflammatory potential of ethanolic aerial root extracts of Ceriops decandra and Ceriops tagal: Supported by molecular docking and ADMET analysis

Ceriops decandra (Griff.) (CD) and Ceriops tagal (Perr.) (CT) are two mangrove plants of the Sundarbans distributed along the coastal areas of South Asia and South Pacific Africa. Traditionally, these plants are used to treat diabetes, pain, angina, hemorrhage, and ulcer. In this study, we investigated the antioxidative, antihyperglycemic, analgesic, and anti-inflammatory potential of the aerial roots of CD and CT. At first, the antioxidative potential of CD and CT ethanolic extracts were investigated qualitatively and quantitatively by 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical and hydrogen peroxide scavenging assays and by determining total antioxidant capacity. The total phenolic, flavonoid, tannin, and terpenoid contents of CD and CT were also estimated. The extracts' antihyperglycemic, analgesic, and anti-inflammatory potential were evaluated by oral glucose tolerance test, acetic acid-induced writhing test, and formaldehyde-induced paw-edema test, respectively. In vitro α-glucosidase and α-amylase enzyme inhibitory activities were also assessed. The CD and CT extracts were also analyzed using GCMS for the presence of phytochemicals. Then, molecular docking was carried out with α-glucosidase, α-amylase, cyclooxygenase-II (COX-II), 3-lipoxygenase (3-LOX) enzymes using the compounds found in GCMS analysis as well as the previously reported compounds from CD and CT. Finally, the pharmacokinetic and toxicological profiles of eight selected compounds were assessed with SwissADME and admetSAR server. In the antioxidative, antihyperglycemic, analgesic, and anti-inflammatory activity tests, CT extract showed a greater potential than CD extract. In addition, CT extract demonstrated higher α-glucosidase enzyme inhibitory activity in comparison to CD extract although CD extract exhibited better α-amylase enzyme inhibitory activity. Molecular docking studies revealed the presence of potentially bioactive compounds in both CD and CT. 2-(2-methylphenyl)-1-phenyl-(z)-1-propene of CD demonstrated good binding affinities for α-glucosidase, COX-II, and 3-LOX. In addition, 5S*,8S*,9S*,10R*,13S*)-18-hydroxy-16-nor-3-oxodolabr-4(18)-en-15-oic acid had high binding interactions for both α-glucosidase and α-amylase while 2′,5,5′-tetramethyl-1,1′-biphenyl, 2-methyl-4-(3′-phenylpropyl)piperidine and decandrin C had high binding interactions for both COX-II and 3-LOX. Finally, 5S*,8S*,9S*,10R*,13S*)-18-hydroxy-16-nor-3-oxodolabr-4(18)-en-15-oic acid, decandrin C, 2-(2-methylphenyl)-1-phenyl-(z)-1-propene and 2-methyl-4-(3′-phenylpropyl)piperidine demonstrated better pharmacokinetic and toxicological properties in the ADMET analysis compared to the others. Hence it can be concluded that the present study supports the traditional usage of CD and CT for diabetes and pain and reveals the presence of bioactive phytochemicals in both.

Determination of Phenolic and Flavonoid Content, Antioxidant and α-Amylase Inhibitory Activity of Leaf and Flower Extracts of Clerodendrum infortunatum and Hibiscus rosa sinensis Growing in Bara Nepal

In the human body, oxidative stress imposed due to the increase in the concentration of free radicals such as reactive oxygen species (ROS) contributes to the initiation and progression of different diseases. The synthetic antioxidants have low efficacy with side effects, for that plant-derived natural antioxidant can prevent oxidative stress by reducing the risk of having these diseases. In the present study, the methanolic extracts of two traditionally used medicinal plants (leaf and flower) have tested for their antioxidant capacity, α-amylase enzyme inhibitory activity and determination of total phenolic and flavonoid content in the plant extracts. The antioxidant activity was evaluated by a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. The highest DPPH radical scavenging was shown by Clerodendrum infortunatum (IC50 = 71.95±0.51μg/mL) whereas leaf and flower of Hibiscus rosa sinensis showed moderate antioxidant activity (IC50 = 98.74±1.91 and 117.23±7.72 μg/mL) respectively. Among the tested plant extracts, the highest amount of total phenolic and flavonoid content was found in the methanolic extract of C. infortunatum with TPC of 87.07±9.22 mg GAE/g and TFC 34.40±2.00 mg QE/g. The antidiabetic activity of plant extracts was evaluated by the α-amylase enzyme inhibition assay. The leaf extract of C. infortunatum showed moderate α-amylase inhibition activity (IC50 = 118±4.80 μg/mL) whereas the standard acarbose has (IC50 = 12.96±0.22 μg/mL).

The inhibitory effect of α-amylase enzyme from fraction and isolate of mareme leaves (Glochidion arborescens Blume.)

Mareme leaves (Glochidion arborescens Blume) is a plant that has potential as an antidiabetic agent. A previous study reported that ethanol extract of Mareme leaves exhibits active inhibitory activities of α-amylase enzyme. This study aimed to determine the α-amylase enzyme inhibitory activities of fraction and isolate from Mareme leaves. The ethanol extract of Mareme leaves was fractionated by using vacuum liquid chromatography. Then, it was isolated and purified using a chromatotron, a radial chromatographic method. The fraction and isolate were assayed for α-amylase enzyme inhibitory activities. The result indicated that Mareme leaves could inhibit an active α-amylase enzyme inhibitory activity with an IC50 value of 28.262 ppm. Mareme leaves isolate has a very active inhibition (IC50 value = 21.024 ppm) comparable with acarbose, a positive control (IC50 value = 19.486 ppm). In addition, the statistical analysis using the t-test also resulted in a significant difference in average inhibition of α-amylase enzyme between fraction and isolate of Mareme leaves. The study concludes that the fraction and isolate of Mareme leaves are potential inhibitors of α-amylase enzyme in reducing calorie intake. As such, this plant extract has been proven that it could be a potential antidiabetic or anti-obesity agent to prevent or treat chronic diseases.

Brotowali (Tinospora crispa L.) stem extract activity as an α-Amylase enzyme inhibitor

Introduction: Reducing glucose absorption in the gastrointestinal tract is one of the strategies for treating diabetes mellitus. The condition of treating diabetes mellitus can be achieved by inhibiting the activity of the α-amylase enzyme. Brotowali (Tinospora crispa L.)/Tc has antihyperglycemic activity; compounds contained in the Tc stem can inhibit the activity of the α-amylase enzyme. The extraction of the Tc stem used for treatment was done with water and/or ethanol. Aim: This study aimed to measure the inhibitory activity of the α-amylase enzyme in both aqueous and ethanolic extract Tc stem. Methods: The inhibitory activity test of the α-amylase enzyme was carried out using the UV-visible spectrophotometric method. Results: The aqueous extract and ethanolic extract of Tc stem had α-amylase enzyme inhibitory activity with IC50 values of 11.660 ± 0.310 mg/mL and 10.348 ± 0.313 mg/mL, respectively. The Tc stem extracted with water or ethanol can be used as an antidiabetic drug.

Antidiabetic profiling, cytotoxicity and acute toxicity evaluation of aerial parts of Phragmites karka (Retz.)

Ethnopharmacological relevancePhragmites karka (Retz.) of family Poaceae is a pristine tropical plant that is well known to the local healers for ailments of diabetes, fever, diarrhea and CNS depression but lacks the scientific evidence behind its traditional usage. Hence, we explicated this plant to find the scientific basis of its traditional utilization. Aim of the studyThe current study aims to find out the antidiabetic potential, toxicity after oral administration and in vitro cytotoxic activity of aerial parts of the plant on HeLa cells. MethodsThe plant was extracted with methanol by maceration and the crude extract was then subjected to solvent partitioning with modified Kupchan method for preparing several fractions. Phytochemical screening and total phenolic content of the plant was first determined through established procedures. Acute toxicity of the plant was studied by orally administering a single high dose (5000 mg/kg) of drug. Cytotoxicity of the methanolic plant extract was determined by measuring the percentage of cell viability on human cervical cancer cell lines, HeLa. In vitro antidiabetic activity was determined through iodine starch and DNSA (3,5-dinitrosalicylic acid) method of α-amylase inhibition. Finally, in vivo oral glucose tolerance test and alloxan induced antidiabetic activity test was performed at 150 and 300 mg/kg body weight doses of plant extract to confirm the in vivo antidiabetic activity. ResultsNo mortality was demonstrated by Phragmites karka in the acute toxicity test. However, signs of cellular toxicity was observed and histopathological studies on major organs exhibited necrosis in liver and kidney. In vitro cytotoxicity assay revealed the death of HeLa cells by DCM (dichloromethane) and n-hexane fractions of plant extract at 100 and 10 μg/mL concentrations. The IC50 value of the fractions were later evaluated by MTT assay (316.1 and 96.7 μg/mL for n-hexane and DCM fractions, respectively). In the iodine starch and DNSA method of α-amylase enzyme inhibitory activity test, substantial inhibition of enzyme was observed with the IC50 values of 2.05 and 2.08 mg/mL, respectively. In the in vivo antidiabetic activity test, considerable reduction in blood glucose level of diabetic mice was detected in both oral glucose tolerance test and alloxan induced antidiabetic activity test. In addition, the microscopic examination of pancreas showed noticeable recovery of pancreatic β cells and the blood lipid profile analysis represented a significant (p < 0.05) reduction of total cholesterol, LDL (low density lipoprotein) and triglyceride level in plant extract treated mice. ConclusionResults of this study reveals that the Phragmites karka extract is toxic at cellular level after oral administration and cytotoxic when tested on HeLa cells. The plant also evidenced hypoglycemic property, possibly through the inhibition of α-amylase enzyme and recovered the pancreatic beta cells along with the improvement of lipid profile of diabetic mice. However, robust studies on this plant is required to isolate the bioactive compounds, elucidate structures and evaluate their mechanism of actions in support of our findings. ClassificationToxicology and Safety, Quality Traditional Medicine.

ESTIMATION OF PHENOLIC CONTENT, FLAVONOID CONTENT, ANTIOXIDANT, AND ALPHA-AMYLASE INHIBITORY ACTIVITY OF SOME SELECTED PLANTS FROM SIRAHA DISTRICT NEPAL

Objectives: The purpose of this research was to estimate the phenolic content, flavonoid content, antioxidant, antibacterial, and α-amylase inhibitory activity of some selected plants such as Anethum sowa, Trigonella foenum-graecum, Lepidium sativum, Cuscuta reflexa, Eclipta alba, Leucas cephalotes, and Tinospora cordifolia collected from Siraha district of Nepal using in vitro studies.&#x0D; Methods: Methanol extracts of these medicinal plants were prepared by cold percolation method. Preliminary phytochemical screening was performed by color differentiation method. Total phenolic and flavonoid content were estimated by Folin-Ciocalteu reagent method and aluminum chloride colorimetric method. Antioxidant potential was evaluated by 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay. Furthermore, the α-amylase enzyme inhibitory activity was studied using starch as a substrate, pancreatic α-amylase as the enzyme, and acarbose as standard.&#x0D; Results: Phytochemical screening showed that the plant extracts were found a rich source of secondary metabolites. The phenolic content estimation showed T. foenum-graecum 939.764±0.01, L. sativum 551.63±0.02, A. sowa 306.34±0.06, L. cephalotes 233.19±0.03, T. cordifolia 211.76±0.02, E. alba 202.67±0.02, and C. reflexa Roxb. 145.09±0.09 mg milligram gallic acid equivalent per gram. The flavonoid content estimation showed T. cordifolia 852.07±0.11, L. sativum 553.81±0.05, E. alba 322.13±0.02, A. sowa 329.02±0.05, L. cephalotes 164.93±0.02, and C. reflexa Roxb. 146.37±0.00 mg milligram quercetin equivalent per gram. The antioxidant potential showed by E. alba IC50 33.48±0.82 μg/ml and the values ranged from E. alba 33.48±0.82 to A. sowa 47.62±1.09 μg/ml. The α-amylase inhibitory activity showed by A. sowa 76.78±2.00–E. alba 777.36±9.66 μg/ml. The result of brine shrimp toxicity showed LC50 value &gt;1000 μg/ml. Among the seven plant extracts, only the plant extract of E. alba showed a zone of inhibition 14 mm against Staphylococcus aureus.&#x0D; Conclusions: The plant extract of T. foenum-graecum showed the highest phenolic content, and T. cordifolia showed the highest flavonoid content. The highest antioxidant potential exhibited by E. alba and the highest α-amylase inhibition activity showed by A. sowa. The plant extract of E. alba showed moderate antibacterial activity against S. aureus. All plant extracts were found non-toxic against brine shrimp larvae although further study is needed to assess its mechanism of action.

Carlina curetum plant phytoconstituents, enzymes inhibitory and cytotoxic activity on cervical epithelial carcinoma and colon cancer cell lines

IntroductionPlant products are a rich source of pharmacologically active molecules and are considered an important and attractive field of scientific investigation for the development of new drugs. The present study aimed to assess the α-amylase, α-glucosidase and lipase enzymes inhibitory activities and the cytotoxic effects of Carlina curetum four solvents fractions in order to better understand the anti-obesity, hypoglycemic and anticancer effects of this plant. MethodsSeveral qualitative and quantitative phytochemical tests were performed on Carlina curetum solvent fractions utilizing standard phytochemical procedures, followed by an investigation into their ability to inhibit the enzymes α-amylase, α-glucosidase, and lipase and an assessment of cytotoxic activity against HeLa and Colo-205 cells using standard biochemical and biotechnological methods. ResultsThe results revealed that the aqueous and methanol fractions had the highest α-amylase enzyme inhibitory activity with IC50 values of 21.37 ± 0.31 and 30.2 ± 0.42 μg/mL, respectively, in comparison with Acarbose, which had an IC50 value of 28.18 ± 0.42 μg/mL. The methanol fraction showed potent α-glucosidase inhibitory activity with an IC50 value of 27.54 ± 4.28 μg/mL; the α-glucosidase inhibitory activity Acarbose was 37.15 ± 0.33 μg/mL. The hexane fraction had greater anti-lipase activity than Orlistat. In addition, 0.5 mg/mL of the C. curetum acetone and hexane fractions had pronounced cytotoxic effects on the Colo-205 cancer cell line, and 0.625 mg/ml of the C. curetum hexane fraction had potential cytotoxic effects against the cervical epithelial carcinoma (HeLa) cell line. ConclusionThis study revealed that C. curetum has potential α-amylase, α-glucosidase, porcine pancreatic lipase enzyme inhibitory activity and cytotoxic activity against the HeLa and Colo-205 cancer cell lines, which indicates the presence of biologically active and cytotoxic compounds in this plant species. This may be considered a challenge for developing bioactive compounds in diabetes, obesity and cancer management.

Beneficial lactic acid bacteria based bioprocessing of cashew apple juice for targeting antioxidant nutraceutical inhibitors as relevant antidotes to type 2 diabetes

Abstract Beneficial lactic acid bacteria (LAB) were rationally targeted to bioprocess underutilized byproduct cashew apple juice (CAJ) for enhancing phenolic bioactive-associated antioxidant, anti-hyperglycemic, and anti-hypertensive properties for developing antioxidant nutraceutical antidotes relevant for type 2 diabetes. Lactobacillus plantarum, L. casei and Bifidobacterium longum were used to bioprocess CAJ and then aqueous and 12% ethanol extracts of fermented CAJ were analyzed for total soluble phenolic (TSP) content, phenolic acid profile (HPLC), total antioxidant activity, type 2 diabetes relevant α-glucosidase, and α-amylase enzyme inhibitory activities and hypertension relevant angiotensin-I-converting (ACE) enzyme inhibitory activity using in vitro assay models. Overall, high TSP content, moderate to high antioxidant activity, moderate ACE inhibitory activity and high α-glucosidase and α-amylase enzyme inhibitory activity was observed in bioprocessed CAJ. Therefore, this study suggests that bioprocessing of CAJ from cashew byproducts with L. plantarum and L. casei is an effective strategy for obtaining type 2 diabetes relevant antioxidant nutraceuticals.

In vitro inhibition of a-amylase enzyme, phytochemical study and antioxidant capacity for cupressus sempervirens extracts growing in arid climat

Cupressus sempervirens (Cupressaceae) “cypress” is growing in the Mediterranean basin; it is a medicinal and an aromatic plant it used in treatment of many diseases in traditional medicine. This paper aims to determining antioxidant potential of C. sempervirens extracts and evaluating their inhibitory effects on α-amylase enzyme. The antioxidant properties of the crude extract and its factions were assessed by phosphomolybdenum, DPPH assay and α-amylase inhibitory activity was evaluating by spectrophotometric methods. Results showed that all extracts have high reductive activity better than butylated hydroxyanisole (BHA) with Ascorbic Acid Equivalent Anti-oxidant Capacity (AEAC) values ranged between 789.04 ± 32.47 and 28.18 ± 3.09 mM, while the greatest radical scavenging activity was found at ethyl acetate fraction with IC50 value 10 μg/ml, whereas in α-amylase enzyme inhibitory activity, ethyl acetate fraction of fruits showed the highest α-amylase inhibitory activity (43.35%). While the inhibitory patterns of ethyl acetate fraction of fruits (EFF) and ethyl acetate portion of tannin extract for leaves (EFT) were competitive type.

Phenolic contents, in vitro antioxidant activities and biological properties, and HPLC profiles of free and conjugated phenolics extracted from onion, pomegranate, grape, and apple

ABSTRACTThis study quantified the free and conjugated phenolic content of extracts from selected Liliaceae (white and red onion), Punicaceae (red and pink pomegranate), Vitaceae (zini, red globe, and baladi grape), and Rosaceae (yellow and red apple) cultivated family plants and evaluated their antioxidant activities and beneficial properties toward diabetes and hypertension. Free and bound phenolics were extracted from plants, and total phenolic contents were evaluated. Antioxidant activities were assessed, as well as the inhibitory effects of angiotensin I-converting enzyme (ACE) and α-amylase and α-glucosidase activities. Liquid chromatography–mass spectrometry/mass spectrometry (LC–MS/MS) measured the individual phenolic content in both free and bound extracts. The free phenolic contents in the selected plants were higher than bound phenolic contents, except for in zini and red globe grapes. In onion, the highest antioxidant activity was observed in the bound phenolic extract (49.6–56.9%). In pomegranates, grapes, and apples, the highest antioxidant activities were obtained in free phenolic extracts at 30°C with values of 65.3% to 74.2%, 39.6% to 47.6%, and 49.5% to 55.9%, respectively. ACE was 100% inhibited by the free phenolic extract at 30°C from white onion and by the bound phenolic extract after acid hydrolysis of red onion. The highest α-amylase enzyme inhibitory activity was obtained in free phenolic extracts at 60°C of both red pomegranates and zini grapes. The highest α-glucosidase inhibition activity (99.3–99.6%) was found in free phenolic extracts at 30°C from red and pink pomegranates. Reverse phase HPLC revealed two predominant groups of free and bound phenolics identified in onion, pomegranate, grape, and apple.

Assessment of the Antioxidative Properties of Hyphaene Thebaica Fruit and Its Comparative Inhibitory Activities with Butylhydroxylanisole on Α-Amylase and Α-Glucosidase Enzymes

1.1. Aim: To assess the antioxidant capacity of Hyphaene thebaicaand investigate its interaction with enzymes linked with type -2-diabetes (α-amylase and α-glucosidase) in comparison with a purified antioxidant compound, Butylhydroxylanisole (BHA). 1.2. Methods:One gram (1g) of the sample was weighed into 20mL of distilled water and was left for 24 hours, for the aqueous preparation. The phenolic contents (total phenol and total flavonoid), ABTS• (2,2_-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) and 1,1-diphenyl-2-picrylhydrazyl (DPPH), scavenging activity was also studied. The ability of the aqueous hyphaene thebaicafruit (AHTF) extract and BHA, to inhibit diabetes enzymes in rat pancreas in vitro were investigated. Furthermore, the major phytochemical present in AHTF were also identified. 1.3. Results:The result showed that AHTF extract had some antioxidant capacity, it had a higher α-amylase enzyme inhibitory activity than that of BHA. But BHA exhibited the higher potentials. 1.4. Conclusion:This may signify that the antidiabetic potential of hyphaene thebaica, is a synergy of both the antioxidant capacity and free radical scavenging activities, linked with the added phytochemicals present, especially flavonoids and alkaloids, which where both present. Though BHA has a more favourable result than the natural, cheap, available hyphaene thebaicathe fruit can be useful as nutraceutical or active agent in the formulation of herbal drugs.

RETRACTED: Anti-diabetic activity of Swertia corymbosa (Griseb.) Wight ex C.B. Clarke aerial parts extract in streptozotocin induced diabetic rats

Swertia corymbosa locally called as Shirattakuchi have a long history of use in Ayurveda herbal preparations in Indian traditional system of medicine. It has been used in folklore medicine for the treatment of diabetes. The present study aimed to investigate the effect of the methanolic extract of Swertia corymbosa (SC) in diabetic and to analyze its chemical composition by HPLC-ESI/MS that may correlate with their pharmacological activities. The in vitro anti-diabetic activity of the extracts was measured by using α-glucosidase and α-amylase enzyme inhibitory activity. The methanolic extract of Swertia corymbosa were administered orally (125, 250 and 500 mg/kg, for 28 days) to streptozotocin-induced diabetic rats. Hypoglycemic effects, oral glucose tolerance test, change in body weight and lipid profile, biochemical analysis and histopathological examination were assessed. High-performance liquid chromatography-electrospray ionization/mass spectrometry (HPLC-ESI/MS) method was also developed to analyze the chemical composition. In vitro anti-dabetic study, the methanol extract of SC is found to be a potent inhibitor of α-glucosidase and α-amylase activity. Oral administration of SC and standard drug for 28 days caused a significant decrease in the concentrations of blood glucose level, total cholesterol (TC), serum triglycerides (TGs), low-density lipoprotein-cholesterol (LDL-C), malondialdehyde (MDA) and significant increase in the concentrations of high density lipoprotein-cholesterol (HDL-C), serum insulin and body weight. Furthermore, activities of antioxidative enzymes, including SOD, GPx, GSH and CAT were enhanced dosed dependently with SC. Histopathological studies of the pancreas showed the regeneration of the β-cells by extract which were earlier necrosed by streptozotocin. Ten major compounds such as loganic acid (1), swertiamarin (2), sweroside (3), gentiopicroside (4), isovitexin (5), amoroswertin (6), amarogentin (7), gentiacaulein (8), decussatin (9) and swertianin (10) were analyzed by HPLC-ESI/MS system. These results demonstrate that SC aerial parts of methanolic extract is an effective anti-diabetic and antioxidant activities which provides the scientific proof for the folklore medicine.