Kwang-Deog Moon

Ether fraction of methanol extracts of Gastrodia elata, a traditional medicinal herb, protects against kainic acid-induced neuronal damage in the mouse hippocampus

Gastrodia elata (GE) has been used traditionally for the treatment of convulsive diseases such as epilepsy in oriental countries including South Korea and still occupies an important place in traditional medicine in Asia. We studied the anticonvulsive effect and protective effect of the ether fraction of methanol extracts (EFME) of GE against hippocampal neuronal damage after kainic acid administration in mice. Mice were treated with the EFME of GE (200 or 500 mg/kg per day, p.o.) for 14 days before kainic acid injection (45 mg/kg, i.p.). The EFME of GE (at the dose of 500 mg/kg) delayed the onset time of neurobehavioral change (P<0.01) and reduced the severity of convulsions (P<0.05) and hippocampal neuronal damage in the CA1 (P<0.01) and CA3 (P<0.05) regions. Our results show that The EFME of GE has anticonvulsive effect and putative neuroprotective effect against excitotoxicity induced by kainic acid.

Ethyl ether fraction of Gastrodia elata Blume protects amyloid β peptide-induced cell death

Alzheimers disease is the most common cause of dementia in the elderly. Recently, it has been reported that Alzheimers disease is associated with cell death in neuronal cells including the hippocampus. Amyloid beta-peptide stimulates neuronal cell death, but the underlying signaling pathways are poorly understood. In order to develop anti-dementia agents with potential therapeutic value, we examined the effect of the herbal compound Gastrodia elata Blume (GEB) on neuronal cell death induced by amyloid beta-peptide in IMR-32 neuroblastoma cells. The fractionation of GEB was carried out in various solvents. The hydroxyl radical scavenging effect of the ethyl ether fraction was more potent than any other fractions. In cells treated with amyloid beta-peptide, the neuroprotective effect of the ethyl ether, chloroform, and butanol fractions was 92, 44, and 39%, respectively, compared with control. Taken together, these results suggest that the ethyl ether fraction of GEB contains one or more compounds that dramatically reduce amyloid beta-peptide induced neuronal cell death in vitro.

Scanning electron microscopic observations of dough and bread supplemented with Gastrodia elata Blume powder

Abstract Dough and bread prepared from wheat flour containing varying amounts of added Gastrodia elata Blume (GEB) rhizome powder [0, 0.5, 1.0, 1.5, and 2.0% (w/w)] were examined by scanning electron microscopy (SEM) during fermentation and baking. The structure of the doughs containing added GEB was found to be related to the protein matrix. Further, it was found that large starch granules and strings of small starch granules play an important role in dough structure. The control dough (no added GEB) had a membrane-like structure, and doughs with 0.5–1.0% added GEB had membrane-like structures that were more developed than those of the control, resulting in increased bread volumes. At 1.5–2.0% GEB levels, however, the doughs tended to have mesh-like structures and result in decreased bread volumes. The dough samples with 0.5 and 1.0% added GEB powder had well-developed gluten matrices with evenly dispersed starch granules. These samples resulted in breads with numerous gas bubble eruptions on their surfaces and consequently in larger loaf volumes than were obtained at other levels of GEB. After the second fermentation, many expanded starch granules were observed and these starch granules were dispersed more evenly than after the first fermentation. In 0.5–1.0% GEB bread, many of the large starch granules had expanded after fermentation, but small starch granules had not. The data obtained in this study suggest that bread baked with 0.5–1.0% GEB exhibits a better loaf volume due to the more complete development of a gluten matrix.

Beneficial Effect of Chungkukjang on Regulating Blood Glucose and Pancreatic β-Cell Functions in C75BL/KsJ-db/db Mice

The current study investigated the antidiabetic effect of chungkukjang, a widely used traditional Korean soybean fermentation food, in a type 2 diabetic animal model, C57BL/KsJ-db/db mice. After a 2-week acclimation period, the db/db mice (male, 5 weeks old) were divided into three groups: diabetic control (AIN-76 diet), chungkukjang (5 g/100 g of diet), and rosiglitazone (0.005 g/100 g of diet). The supplementation of chungkukjang induced a significant reduction of blood glucose and glycosylated hemoglobin level, and it improved insulin tolerance compared to the diabetic control group. Plasma and pancreatic insulin levels of the chungkukjang-supplemented group were significantly higher than those of the diabetic control mice, and the plasma glucagon level was also significantly different. The supplementation of chungkukjang and rosiglitazone significantly elevated hepatic glucokinase activity with a simultaneous reduction of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase activity in the db/db mice compared to the diabetic control mice. In addition, the chungkukjang-supplemented group had an increased hepatic glycogen content compared to the diabetic control and rosiglitazone-supplemented groups. Consequently, these results suggest that chungkukjang may be beneficial in improving insulin resistance and hyperglycemia in type 2 diabetic animals that are partly medicated by the regulation of hepatic glucose enzymes and insulin sensitivity in peripheral tissues.

Induction of apoptosis in HT-29 colon cancer cells by crude saponin from Platycodi Radix.

This study examined the apoptotic effects of crude saponins acquired from the roots of Platycodon grandiflorum (SPR) in HT-29 human colon cancer cells. SPR decreased HT-29 cell proliferation in dose- and time-dependent manners by inducing apoptosis via DNA fragmentation and poly (ADP-ribose) polymerase (PARP) cleavage. The apoptosis induced by SPR was associated with the activation of initiator caspases-8 and -9, as well as the effector caspase-3. SPR stimulated Bid cleavage, indicating that the apoptotic action of caspase-8-mediated Bid cleavage leads to the activation of caspase-9. SPR increased the expression of the pro-apoptotic protein, Bax, and decreased the expression of the anti-apoptotic protein, Bcl-2. SPR also increased the expression of the caspase-independent mitochondrial apoptosis factor, AIF, in HT-29 cells. These results indicate that SPR inhibits HT-29 cell proliferation by inducing apoptosis, which may be mediated via both caspase-dependent and -independent pathways.

Safflower seed extract lowers plasma and hepatic lipids in rats fed high-cholesterol diet

Preliminary studies showed that powdered safflower seed lowered the plasma cholesterol concentration in high-fat and high-cholesterol fed rats. These studies were designed to test the hypolipidemic activity of safflower seed extracts prepared with ethanol or hot water. Male rats were fed a high-cholesterol (1%, wt/wt) or high-cholesterol diet supplemented with safflower seed powder (5%, wt/wt; SSP), safflower seed ethanol extract (0.15%, wt/wt; SSE), or safflower seed water extract (0.5%, wt/wt; SSW) for 5 weeks. The safflower seed extracts were supplemented in diets based on 5% raw safflower seeds. All the safflower seed preparations significantly lowered the plasma cholesterol concentration, whereas the plasma triglyceride concentration was only lowered by the supplementation of SSE and SSW. The hepatic total cholesterol contents were significantly lower in the SSW group compared with the control group, whereas the hepatic triglyceride contents were significantly lower in both the SSE and SSW groups compared to control group. Conversely, the hepatic HMG-CoA reductase activities were significantly higher in both the SSE and SSW groups compared with the other two groups. Finally, the hepatic ACAT activities were significantly lower in the SSE group compared to all the other groups. Accordingly, these results indicate that the supplementation of SSE or SSW is more effective than SSP in improving the atherogenic risk factors in high-cholesterol fed rats.

Browning control of fresh-cut lettuce by phytoncide treatment.

Phytoncide essential oil derived from pine leaves was applied for the control of enzymatic browning of fresh-cut lettuce. Changes in the browning characteristics of cut lettuce treated with phytoncide in an water or ethanol solution (1%, v/v) at 10°C were investigated for 12days at 4°C. Other samples dipped in distilled water or 95% ethanol were used as the controls. The samples treated with phytoncide in an ethanol solution showed significantly higher L* values and lower a* values, ΔE values, browning index, phenolic compounds, and enzyme activities (PPO, POD, PAL) related to browning. The samples dipped in distilled water showed the opposite tendency. On the basis of changes in the browning characteristics, anti-browning effects of each treatment, phytoncide in an ethanol solution was the most effective treatment applied. These results suggest that phytoncide treatment could be used as an effective method for controlling enzymatic browning in fresh-cut lettuce.

Supplementation of SK1 from Platycodi Radix Ameliorates Obesity and Glucose Intolerance in Mice Fed a High-Fat Diet

This study investigated the beneficial effects of SK1 on obesity and insulin resistance in C57BL/6 mice, which were fed a high-fat diet (37% calories from fat). SK1 is an edible saponin-rich compound from Platycodi radix. The mice were supplemented with two doses of SK1 (0.5% and 1.0%, wt/wt) for 9 weeks. The body weight, visceral fat mass, and adipocyte area were significantly decreased in the SK1 supplemented-groups in a dose-dependent manner compared to the high-fat group. The SK1 supplement significantly lowered plasma triglycerides, total cholesterol, and free fatty acid levels, whereas it significantly elevated the fecal excretion of lipids in the diet-induced obese mice. Supplementation of SK1 decreased the triglyceride and cholesterol levels and the accumulation of lipid droplets in the liver compared to the high-fat control group. High-fat diet induced glucose intolerance and insulin resistance with the elevation of blood glucose levels compared to the normal group; however, the SK1 supplement significantly improved postprandial glucose levels and insulin resistance index. After 9 weeks of being fed a high-fat diet, the mice presented with significantly increased activities of hepatic fatty acid synthase, fatty acid beta-oxidation, and glucokinase; however, both 0.5% and 1.0% SK1 supplementation normalized these activities. Notably, SK1 supplementation effectively diminished the ratio of fatty acid biosynthesis to fatty acid oxidation compared to the high-fat group. These results indicate that SK1 exhibits a potential anti-obesity effect and may prevent glucose intolerance by reducing body weight and fat accumulation, increasing fecal lipid excretions, and regulating hepatic lipid and glucose metabolism in high-fat fed mice.

Image analysis to evaluate the browning degree of banana (Musa spp.) peel

Image analysis was applied to examine banana peel browning. The banana samples were divided into 3 treatment groups: no treatment and normal packaging (Cont); CO2 gas exchange packaging (CO); normal packaging with an ethylene generator (ET). We confirmed that the browning of banana peels developed more quickly in the CO group than the other groups based on sensory test and enzyme assay. The G (green) and CIE L(∗), a(∗), and b(∗) values obtained from the image analysis sharply increased or decreased in the CO group. And these colour values showed high correlation coefficients (>0.9) with the sensory test results. CIE L(∗)a(∗)b(∗) values using a colorimeter also showed high correlation coefficients but comparatively lower than those of image analysis. Based on this analysis, browning of the banana occurred more quickly for CO2 gas exchange packaging, and image analysis can be used to evaluate the browning of banana peels.

Seed viability and functional properties of broccoli sprouts during germination and postharvest storage as affected by irradiation of seeds.

The viability of broccoli seeds and functional properties, such as ascorbic acid, carotenoid, chlorophyll, and total phenol contents, of broccoli sprouts grown from irradiated seeds were evaluated. The seeds were irradiated using electron beam and gamma ray at doses up to 8 kGy. High germination percentages (>90%) were observed in seeds irradiated at < or =4 kGy, but the yield ratio and sprout length decreased with increased irradiation dose. Irradiation at > or =6 kGy resulted in curling of the sprout roots. Germinated seeds contained higher amounts of nutrients than raw seeds but the nutritional quality of sprouts decreased during postharvest storage. Radiation treatment hampered the growth of irradiated seeds resulting in underdeveloped sprouts with decreased ascorbic acid, carotenoid, and chlorophyll contents. In addition, the decrease in functional content of sprouts was more substantial in samples grown from high-dose (5 kGy) irradiated seeds than that of the low-dose (1 kGy) treated ones. Seed irradiation did not negatively affect the total phenol content of sprouts. In general, electron beam and gamma irradiation of broccoli seeds showed similar effects on the viability and functional properties of sprouts.