• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.6
• /
• pp.917-923
• /
• 2013

This study investigated the enzyme inhibitory effects of ethanol extracts from the different parts of rough rice (Oryza sativar L.) from its germination period. Rough rice was germinated at $37^{\circ}C$ for 6 days, then separated into hull+sprout and brown rice. ${\alpha}$-Glucosidase inhibitory activity had the highest value (39.38%) in hull+sprout extracts after 5 days of germination. ${\alpha}$-Amylase and DPP-4 inhibitory activity had the highest values (75.32% and 47.77%, respectively) in hull+sprout extracts after germination for 5 days. ACE inhibitory activity of hull+ sprout extracts increased from 43.16% at the beginning to 58.60% at 5 days, while brown rice extracts increased this activity from 0.88% at the beginning to 14.50% at 4 days. The xanthine oxidase inhibitory activity of hull+ sprout extracts increased from 62.02% at the beginning to 64.49% at one day, and then decreased. Lipase inhibitory activity had its highest value (55.17%) in hull+sprout extracts after germination for 5 days. These results indicate that the optimal germination period for increasing enzyme inhibitory activities may be 5 days, and that hull+sprout extracts have a higher enzyme inhibition activity than brown rice.

• Journal of Ginseng Research
• /
• v.44 no.2
• /
• pp.362-372
• /
• 2020

Background: The non-saponin fraction of Korean Red Ginseng has been reported to have many biological activities. However, the effect of this fraction on anti-diabetic activity has not been elucidated in detail. In this study, we investigated the effects of KGC05P0, a non-saponin fraction of Korean Red Ginseng, on anti-diabetic activity in vitro and in vivo. Methods: We measured the inhibition of commercially obtained α-glucosidase and α-amylase activities in vitro and measured the glucose uptake and transport rate in Caco-2 cells. C57BL/6J mice and C57BLKS/J^db/db (diabetic) mice were fed diets with or without KGC05P0 for eight weeks. To perform the experiments, the groups were divided as follows: normal control (C57BL/6J mice), db/db control (C57BLKS/J^db/db mice), positive control (inulin 400 mg/kg b.w.), low (KGC05P0 100 mg/kg b.w.), medium (KGC05P0 200 mg/kg b.w.), and high (KGC05P0 400 mg/kg b.w.). Results: KGC05P0 inhibited α-glucosidase and α-amylase activities in vitro, and decreased glucose uptake and transport rate in Caco-2 cells. In addition, KGC05P0 regulated fasting glucose level, glucose tolerance, insulin, HbA1c, carbonyl contents, and proinflammatory cytokines in blood from diabetic mice and significantly reduced urinary glucose excretion levels. Moreover, we found that KGC05P0 regulated glucose production by down-regulation of the PI3K/AKT pathway, which inhibited gluconeogenesis. Conclusion: Our study thereby demonstrated that KGC05P0 exerted anti-diabetic effects through inhibition of glucose absorption and the PI3K/AKT pathway in in vitro and in vivo models of diabetes. Our results suggest that KGC05P0 could be developed as a complementary food to help prevent T2DM and its complications.

• Food Science and Preservation
• /
• v.25 no.1
• /
• pp.124-135
• /
• 2018

This study investigated the nutritional properties and biological activities of Ganoderma lucidum (GL). The round type of GL contained higher carbohydrate content, while the Nokgak type of GL contained higher crude ash, crude fat, and crude protein content. The most abundant amino acid, fatty acid, mineral, and soluble vitamin observed were valine (round type: 11.90 mg/g and Nokgak type: 17.18 mg/g), linoleic acid (round type: 47.56% and Nokgak type: 75.68%), potassium (round type: 116.50 mg/100 g and Nokgak type: 184.36 mg/100 g), and vitamin B3 (round type: 1.78 mg/100 g and Nokgak type: 1.81 mg/100 g), respectively. In addition, the ${\beta}$-glucan content were 34.15 g/100 g (round type) and 30.07 g/100 g (Nokgak type). The GL 70% ethanol extract at $40^{\circ}C$ showed higher radical scavenging as well as carbohydrate and lipid enzyme inhibition than other conditions. At 1 mg/mL of treatment with the 70% ethanol extract at $40^{\circ}C$ of round type GL, the DPPH, ABTS, hydroxyl radical scavenging, and ${\alpha}$-glucosidase, ${\alpha}$-amylase, and pancreatic lipase inhibition activities obtained were approximately 92.85, 99.74, 58.09, 89.68, 44.68, and 67.56%, respectively.

• Journal of Life Science
• /
• v.27 no.1
• /
• pp.32-37
• /
• 2017

Cyanidin-3-O-glucoside (C3G) shows anti-inflammatory and antioxidant effects; however, its effect on postprandial blood glucose levels remains unknown. Alpha-glucosidase inhibitors regulate post-prandial hyperglycemia by impeding carbohydrate digestion in the small intestine. Here, the effect of C3G on ${\alpha}-glucosidase$ and ${\alpha}-amylase$ inhibition and its ability to ameliorate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice were evaluated. ICR normal and STZ-induced diabetic mice were orally administered soluble starch alone or with C3G or acarbose. The half-maximal inhibitory concentrations of C3G for ${\alpha}-glucosidase$ and ${\alpha}-amylase$ were 13.72 and $7.5{\mu}M$, respectively, suggesting that C3G was more effective than acarbose. The increase in postprandial blood glucose levels was more significantly reduced in the C3G groups than in the control group for both diabetic and normal mice. The area under the curve for the diabetic mice was significantly reduced following C3G administration. C3G may be a potent ${\alpha}-glucosidase$ inhibitor and may delay dietary carbohydrate absorption.

• Korean Journal of Food Science and Technology
• /
• v.48 no.4
• /
• pp.341-346
• /
• 2016

The AMY2B gene, encoding human pancreatic ${\alpha}$-amylase isozyme (HPA II), was expressed in Pichia pastoris, and the effects of chloride ions on HPA II activity toward starch substrates were investigated. As seen with chloride ion-dependent ${\alpha}$-amylases-including HPA I, the isozyme of HPA II-chloride ions increased enzyme activity and shifted the optimal pH to an alkaline pH. The activity enhancement by chloride was more significant at pH 8 than that at pH 6, suggesting that the protonation state of the general acid/base catalyst of HPA II was important for the hydrolysis of starches at an alkaline pH because of the increase in its $pK_a$ by chloride ions. The turnover values for cereal starches as the substrates markedly increased in the presence of chloride by up to 7.2-fold, whereas that for soluble starch increased by only 1.7-fold. Chloride inhibited substrate hydrolysis at high substrate concentrations, with $K_i$ values ranging from 6 to 15 mg/mL.

• Microbiology and Biotechnology Letters
• /
• v.34 no.2
• /
• pp.109-114
• /
• 2006

Yam has been recognized as healthy food due to its various biological activities, such as anti-obesity, antimicrobial, anticancer and immuno-stimulation activities, and its consumption has been increased during last decades. In this study, to investigate low-temperature, long-term storage of yam and to develop processed yam products, yam-putrefactive psychrotrophic bacteria were isolated from rotted yam and identified based on BBL identification system, fatty acid analysis in cell membrane and 16S rDNA sequence analysis. The putrefaction activity of isolated thirteen bacteria was evaluated using yam-slices (NaOCl-treated, autoclaved yam and without treatment), and YAM-10 and YAM-12 were identified as major psychrotrophic putrefactive bacteria. Both YAM-10 (Pseudomonas cepacia) and YAM-12 (Pseudomonas rhodesiae) bacteria grew well at 4$\sim$12$^{\circ}C$ and showed strong activity of polymer degrading enzymes, especially amylase, carboxy methyl cellulase and xylanase, at 20$^{\circ}C$. But they failed to grow at acidic pH (<5) or alkaline pH (>10). Our results suggested that the control of psychrotrophic Pseudomonas sp. by pH change and inhibition of polymer degrading enzymes, such as amy-lase, are necessary to long-term storage of yam.

• Journal of Life Science
• /
• v.28 no.4
• /
• pp.421-428
• /
• 2018

Postprandial hyperglycemia plays an important role in the development of Type 2 Diabetes and diabetic complications. Controlling postprandial hyperglycemia is the most important factor for reducing the risks of diabetic complications in Type 2 diabetic patients. This study was designed to determine whether Portulaca oleracea L. extract suppresses the activation of carbohydrate-digesting enzymes, and lowers postprandial hyperglycemia in diabetic mice through streptozotocin. P. oleracea was extracted with either 80% ethanol (PEE) or water (PWE), and the extract solutions were concentrated. The ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibition assays were performed using the chromogenic method. Normal mice and STZ-induced diabetic mice were orally treated with PEE, PWE (300 mg/kg of body weight) or acarbose (100 mg/kg of body weight), with soluble starch (2 g/kg of body weight). The ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory effectiveness by PEE were markedly more effective than PWE, and both extracts indicated a higher effectiveness than the acarbose (positive control). The rise in postprandial blood glucose due to starch loading was markedly inhibited in the PEE group when compared to the control group in diabetic and normal mice. Furthermore, the area under the concentration-time curve values were markedly declined by the PEE injection in the diabetic group when compared to that exerted for the control group. These results demonstrate that P. oleracea extracts lower postprandial hyperglycemia by inhibiting carbohydrate-digesting enzymes, and that the ethanol extract is more efficacious than the water extract.

• Korean journal of applied entomology
• /
• v.10 no.1
• /
• pp.23-30
• /
• 1971

This work was carried out to study the chemical properties, the activity of several enzymes, chemical components and the respiratory intensity of mite galls on the leaves of Lycium chinense MILL. caused by Eriophyes kuke KISHIDA. The activities of catalase and peroxidase were higher in the gall tissue, when compared to the healthy tissue, and were increased as tile gall developed. The activity of phosphorylase of the healthy tissue seemed to be higher than that of the large gall l tissue, considering the competitive inhibition of phosphomonoeoterase and $\beta-amylase$, The activities of invertase and $\beta-amylase$ were about two times higher in the large sail tissue than those of the healthy tissue. The content of the crude protein was $20\%$ higher in the small gall tissue than that of the healthy leave tissue, and decreased as the gall matured. On the other hand, the reducing sugar level was less in the small gall tissue than that of the healthy leaves, but as the gall grew, the content of reducing sugar of the gall tissue was increased. The contents of phosphorus and tannin were increased gradually as the gall matured, and their content showed about two times higher than those of the healthy. The matured gall tissue showed higher $QO_2$ than the healthy tissue. On the other hand, the matured gall tissue presented lower $QCO_2$ than the healthy tissue, and the RQ of the healthy tissue was higher than that of the gall tissue.

• Food Science and Preservation
• /
• v.20 no.5
• /
• pp.699-704
• /
• 2013

Buckwheat Soksungjang (BS) is a bealmijang manufactured with buckwheat and soybeans. We manufactured BS using Bacillus subtilis HJ18-4 (HJ18-4), which has high enzyme activities and antibacterial effects. HJ18-4 was inoculated in a different process during the BS manufacturing, which was the meju-making time (Treat 1), and the salt water time was added (Treat 2). The physiochemical and microbial characteristics of the BS were analyzed. As a result, the total aerobic counts (7~8 log CFU/mL) in the BS increased after 15 days of fermentation. Especially, Treat 1 showed higher total aerobic counts and amino-type nitrogen (65.38~202.52 mg%) than Treat 2. During the BS fermentation, the reduction of the sugar contents and the enzyme (protease and amylase) activities decreased. In the relative quantitative expression level of PlcR, Treat 1 did not show toxin gene expressions at the end of the fermentation on Day 23. Treat 1 showed suitable B. cereus physiochemical quality characteristics and inhibition effects. When the modified-form type of fermented soybean paste was manufactured with a single starter, it could not reproduce the natural fermentation quality. These results suggest that the addition of a starter (HJ18-4) in the Meju manufacturing process could enhance the quality characteristics of the manufactured BS via natural fermentation and by suppressing B. cereus.

• The Korean Journal of Mycology
• /
• v.40 no.4
• /
• pp.235-243
• /
• 2012

We studied the effect of fermented Rhus verniciflua stem bark (FRVSB) extract (used in herbal med-icine by Koreans) on the microbial growth and enzyme activity of 12 soybean-fermenting microorganisms, including Bacillus spp., lactic acid bacteria, yeast, and other harmful bacteria. The ethanol and methanol extracts of FRVSB inhibited the growth of Bacillus subtilis, Bacillus licheniformis, Bacillus cereus, and Zygosaccharomyces rouxii, and in the disk diffusion assay, their inhibition zone diameters were 11.06-12.23, 12.32-18.38, 11.47-11.84, and 13.59-14.21 mm, respectively. The water extract did not show any inhibitory effect. In fact, the water extract addition enhanced the growth of B. subtilis and B. licheniformis by 1.3-4.5 fold and that of B. cereus by 1.2-1.4 fold. However, the water extract did not affect the growth of Lactobacillus plantarum, Lactobacillus mesenteroides, Saccharomyces cer-evisiae, and Escherichia coli. The addition of water extract increased the amylase and protease activity of B. subtilis and B. licheniformis.