• Nutrition Research and Practice
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• v.3 no.4
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• pp.272-278
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• 2009

Postprandial hypoglycemic effect of mulberry leaf (Morus alba L.) was compared in two animal models: Goto-Kakizaki (GK) rats, a spontaneous non-obese animal model for type II diabetes, and their counterpart control Wistar rats. First, the effect of a single oral administration of mulberry leaf aqueous extract (MLE) on postprandial glucose responses was determined using maltose or glucose as substrate. With maltose-loading, MLE reduced peak responses of blood glucose significantly in both GK and Wistar rats (P < 0.05), supporting the inhibition of $\alpha$-glucosidase by MLE in the small intestine. With glucose-loading, MLE also significantly reduced blood glucose concentrations, measured at 30 min, in both animal models (P < 0.01), proposing the inhibition of glucose transport by MLE. Next, dried mulberry leaf powder (MLP) was administered for 8 weeks by inclusion in the diet. By MLP administration, fasting blood glucose was significantly reduced at weeks 4 and 5 (P < 0.05), but then returned to values that were similar to those of the control at the end of experimental period in GK rats. Insulin, HOMA-IR, C-reactive protein, and triglycerides tended to be decreased by MLP treatment in GK rats. All other biochemical parameters were not changed by MLP administration in GK rats. Collectively, these findings support that MLE has significant postprandial hypoglycemic effect in both non-obese diabetic and healthy animals, which may be beneficial as food supplement to manage postprandial blood glucose. Inhibitions of glucose transport as well as $\alpha$-glucosidase in the small intestine were suggested as possible mechanisms related with the postprandial hypoglycemic effect of MLE.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.8-13
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• 2009

This study investigated the hypoglycemic effect of fermented soymilk extract (FSE) in STZ-induced diabetic mice. FSE was prepared via fermentation of soymilk with Bacillus subtilis followed by methanol extraction. The hypoglycemic effect was determined by inhibitory activities against ${\alpha}$-glucosidase and ${\alpha}$-amylase as well as the alleviation of postprandial glucose level. The non-fermented soymilk extract (SE) was used as control in this experiment. FSE showed higher (p<0.05) inhibitory activities than SE against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The $IC_{50}$ values of FSE for ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.77 ancd 0.94 mg/mL, respectively, which were comparable or even superior to those of acarbose (0.79 and 0.68 mg/mL, respectively). In addition, a further suppression on the postprandial blood glucose levels were observed in the FSE than SE group for both STZ-induced diabetic mice and normal mice. Furthermore, FSE significantly lowered the incremental area under the curve (AUC) in the diabetic mice and the AUC in normal mice corroborated the hypoglycemic effect of FSE (p<0.05). Results from this study suggest that FSE may help decrease the postprandial blood glucose level via inhibiting ${\alpha}$-glucosidase and ${\alpha}$-amylase and the usefulness of FSE was proven to be better than SE.

• Preventive Nutrition and Food Science
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• v.17 no.4
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• pp.239-244
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• 2012

This study investigated the hypoglycemic effect of the Padina arborescens extract in STZ-induced diabetic mice. Freeze-dried Padina arborescens were extracted with 80% methanol and concentrated for use in this study. The hypoglycemic effect was determined by inhibitory activities against ${\alpha}$-glucosidase and ${\alpha}$-amylase as well as the alleviation of postprandial blood glucose level. Padina arborescens extracts showed higher inhibitory activities than acarbose, a positive control against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The $IC_{50}$ values of Padina arborescens extracts against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.26 and 0.23 mg/mL, respectively, which evidenced as more effective than observed with acarbose. The increase of postprandial blood glucose levels were significantly suppressed in the Padina arborescens extract administered group than the control group in the streptozotocin induced diabetic mice. Furthermore, the area under the curve (AUC) was significantly lowered via Padina arborescens extract administration in diabetic mice (p 0.05). These results indicated that the Padina arborescens extract might be used as an inhibitor of ${\alpha}$-glucosidase and ${\alpha}$-amylase and delay absorption of dietary carbohydrates.

• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.8-13
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• 2012

This study was designed to investigate whether Sargassum ringgoldianum extract may inhibit ${\alpha}$-glucosidase and ${\alpha}$-amylase activities, and alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. The $IC_{50}$ values of Sargassum ringgoldianum extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.12 mg/mL and 0.18 mg/mL, respectively, which evidenced higher activities than those of acarbose. The blood glucose levels of the Sargassum ringgoldianum extract administered group were significantly lower compared to the control group in the streptozotocin-induced diabetic mice. Moreover, the area under the two-hour blood glucose response curve was significantly reduced and the absorption of dietary carbohydrates was delayed after administration of Sargassum ringgoldianum extract in the diabetic mice. Therefore, these results indicated that Sargassum ringgoldianum extract may help decrease the postprandial blood glucose level via inhibiting ${\alpha}$-glucosidase.

• The Korea Journal of Herbology
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• v.32 no.5
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• pp.39-46
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• 2017

Objective : This study was designed to evaluate the hypoglycemic effects of Helianthus tuberosi Rhizoma extracts and its optimum Heat processing conditions Methods : We investigated the Salivary ${\alpha}$-amylase, pancreas ${\alpha}$-amylase and ${\alpha}$-glucosidase inhibitory activities of extracts from Steam Heated Helianthus tuberosi Rhizoma Ext. The inhibitory activities of a 50% EtOH extract of Steam Heated Helianthus tuberosi Rhizoma Ext against ${\alpha}$-glucosidases were evaluated in this study. Inhibiting these enzymes involved in the absorption of disaccharides significantly decreases the postprandial increase in blood glucose level after a mixed carbohydrate diet. Furthermore, the postprandial blood glucose lowering effect of Steam Heated Helianthus tuberosi Rhizoma Ext. was compared to a known type 2 diabetes drug(Acarbose(R)) in a mice model. Steam Heated Helianthus tuberosus L. Ext significantly reduced the blood glucose increase after glucose loading. Results : The results were confirmed by real-time PCR that after treated with Streptozotocin in L6 cells, induced expression of GLUT4, after the steamed Helianthus tuberosus L. Ext. treated, observed its expression was increased. Steam Heated Helianthus tuberosus L Ext treated 4 hours in L6 cells, cytotoxicity was measured in MTT assay. Its toxicity were 5.7%, 9% and 11.3% at the treatment concentration $12.5{\mu}g/m{\ell}$, $25{\mu}g/m{\ell}$, the $50{\mu}g/m{\ell}$ respectively. Conclusions : Overall, the results of this study indicate that Hypoglycemic effect of Helianthus tuberosi Rhizoma caused by the Steam heat treatment, the optimum Heat processing condition is steamming at $121^{\circ}C$ for 30 min, and it will provide the basis for developing a useful dietary supplement for controlling postprandial hyperglycemia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.821-824
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• 2005

The purpose of this study is to investigate tile effects of the Paecilomyces japonica on blood glucose in non-insulin dependent diabetes mellitus volunteers. During the 3 months of the experimental period, freeze-dried powder of Paecilomyces japonica (2 g/meal) was given to the subjects right before each meal. Paecilomyces japonica caused a significant decrease of $27.5\%\;and\;35.5\%$ in fasting and postprandial blood glucose levels, respectively. There were significant reductions of $28.5\%\;and\;33.5\%$ in fasting and postprandial blood glucose levels of the male subjects, respectively Paecilomyces japonica also significantly decreased in fasting and postprandial blood glucose levels of $26.1\%\;and\;37.3\%$ in female patients after treatment. This study shows that Paecilomyces japonica supplementation significantly lowered the fasting and postprandial glucose levels in NIDDM patients. These effects presumably contribute to the hypoglycemic activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1257-1262
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• 2007

To develop basidiomycetes-fermented cereals with hypoglycemic property, inhibitory effects of basidiomycetes mycelia and basidiomycetes-fermented cereals on postprandial glucose were investigated. In vitro effect of basidiomycetes mycelia on retarding the membrane transport of glucose was compared with pectin. For basidiomycetes mycelia, $13.1{\pm}3.6{\sim}41.8{\pm}8.0%$ of total glucose remained in inner solution of dialysis membrane after dialysis for 120 min, indicating that most of basidiomycetes mycelia might effectively retard membrane transport of glucose. Glucose tolerance of basidiomycetes mycelia and basidiomycetes-fermented cereals was tested on streptozotocin-induced diabetic rats administrated with maltose. Postprandial glucose levels of basidiomycetes mycelia, $389.4{\pm}43.8{\sim}426.3{\pm}49.4mg/dL$, were considerably lower than that of control, $535.3{\pm}78.6mg/dL$, at 30 minutes after maltose administration. Namely, basidiomycetes mycelia showed better postprandial glucose lowering effect than pectin. Brown rice and barley fermented with Paecilomyces japonica showed much lower postprandial glucose level than raw brown rice and barley, especially hypoglycemic effect of barley fermented with Paecilomyces japonica was significant.

• The Journal of Internal Korean Medicine
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• v.42 no.4
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• pp.672-686
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• 2021

Objectives: The purpose of this study is to assess the efficacy and safety of Baekhogainsam-tang for type 2 diabetes without complications by systemic review and meta-analysis of randomized controlled trials (RCTs). Methods: For a systematic review and meta-analysis, we set a key question in accordance with PICOT-SD. We searched the following up to March 31. 2021: PubMed, EMBASE, The Cochrane Library, CNKI, CiNii, KISS, KMBASE, OASIS, and ScienceON. A meta-analysis was conducted by synthesizing the results, including fasting plasma glucose level, postprandial 2-hour plasma glucose level, and Glycated Hemoglobin (HbA1c). Results: A total of five trials are included in this systemic review. The treatment group (Baekhogainsam-tang plus conventional treatment) showed more statistically significant effect than did the control group (conventional treatment only) in fasting plasma glucose level, postprandial 2-hour plasma glucose level, and glycated hemoglobin (HbA1c). Conclusions: Baekhogainsam-tang showed statistically significant effects in hypoglycemic effect and in improving insulin resistance. However, the number of studies included in the meta-analysis was insufficient, and the BIT used in the included studies was not standardized. This topic requires further attention and more clinical research.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.68-71
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• 2007

Cordyceps militaris, Artemisa capillaris, and Fagopyrum esculentum have been known to maintain normal blood sugar levels in folk medicine. We investigated the effects of these nutraceuticals extract supplementations on fasting and postprandial blood glucose in diabetes mellitus patients. The study population consisted of 50 diabetes subjects with a mean fasting blood glucose of 186.8${\pm}$6.2 mg/dl and postprandial blood glucose of 292.8${\pm}$10.3 mg/dl. They consumed 3 tea bags (3g per meal) of the extract of selected plants for 17 weeks. Patients treated with nutraceuticals extract supplementation showed a significant decrease of fasting blood glucose (118.4${\pm}$3.9 mg/dl) and postprandial blood glucose (160.5${\pm}$4.0 mg/dl) in 7 weeks. Nutraceticals extract supplemantation caused a significant decrease of 36.5% and 45% in fasting and postprandial blood glucose levels, respectively, and also significantly decreased HbA1c levels. This study shows that extract of nutraceuticals supplementation significantly lowered the fasting and postprandial blood glucose levels in NIDDM patients. These effects presumably contribute to the hypoglycemic activity.

• Preventive Nutrition and Food Science
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• v.22 no.3
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• pp.166-171
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• 2017

In this study, we investigated whether Sargassum yezoense extract (SYE) could inhibit ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities, and alleviate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Freeze-dried S. yezoense was extracted with 80% ethanol and concentrated for use in this study. The hypoglycemic effect was determined by evaluating the inhibitory activities of SYE against ${\alpha}-glucosidase$ and ${\alpha}-amylase$ as well as its ability to decrease postprandial blood glucose levels. The half-maximal inhibitory concentrations of SYE against ${\alpha}-glucosidase$ and ${\alpha}-amylase$ were $0.078{\pm}0.004$ and $0.212{\pm}0.064mg/mL$, respectively. SYE was a more effective inhibitor of ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities than the positive control, acarbose. The increase in postprandial blood glucose levels was significantly alleviated in the SYE group compared with that in the control group of STZ-induced diabetic mice. Furthermore, the area under the curves significantly decreased with SYE administration in STZ-induced diabetic mice. These results suggest that SYE is a potent inhibitor of ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities and alleviates postprandial hyperglycemia caused by dietary carbohydrates.