• International Journal of Industrial Entomology and Biomaterials
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• v.34 no.2
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• pp.38-44
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• 2017

Mulberry leaves containing 1-deoxynojirimycin (DNJ) have been recognized as a potentially important source for prevent or treat hyperglycemia. However, DNJ content of natural mulberry leaf are as low as 0.1%. Thus, the most effective method for increasing ${\alpha}$-glucosidase inhibitory activity with the DNJ high-production is needed. In this study, we investigated the influence of ${\alpha}$-glucosidase inhibitory activity according to different pH values (6-9) and inoculation amounts (0.1-0.5%) when Bacillus subtilis cultured on mulberry leaf powder media. We confirmed that ${\alpha}$-glucosidase inhibitory activity was difference according to culture conditions of different pH values, inoculation amounts, and fermentation times. The results of mulberry leaf fermentation according to pH values and inoculation amounts were shown that the optimal conditions for ${\alpha}$-glucosidase inhibitory activity were defined as pH 7 and 9, inoculation amount 0.4%, and incubation until 2 to 4 days. These results can be provided a basic data for the optimal culture conditions increasing ${\alpha}$-glucosidase inhibitory activity from mulberry leaf fermentation.

• The Korean Journal of Food And Nutrition
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• v.20 no.1
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• pp.53-62
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• 2007

In this study, physicochemical, microbiological and organoleptic analyses were carried out on cabbage kimchi, a representative fermented food, that was made with 0.5%, 1.0%, and 1.5% mulberry leaf powder during fermentation. This kimchi was then compared to, kimchi without added mulberry leaf powder. The pH values showed minimal differences between the two types of kimchi at the beginning of fermentation. The total acidities were low in every plot of kimchi and increased according to the fermentation. The total microbial cell and Lactobacilus counts increased rapidly in the exponential phase according to the fermentation, and showed little increase in the stational phase. Among the analyzed plots, the lowest population was found in the kimchi containing 1.0% of mulberry leaf powder. This kimchi, in particular, also had the best quality scores, overall acceptance and organoleptic test results during fermentation. Fermentation was slowed in the kimchi with mulberry leaf powder, according to the amount of added as compared to the kimchi without it also showed less acidity. The color appearance, however, of the kimchi with added mulberry leaf powder, was inferior to that of the kimchi without mulberry leaf powder.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.699-709
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• 2017

This study was performed to develop and evaluate functional prepared with optimum mixing of mulberry leaf and fruit powder using response surface method (RSM). In order to develop the optimized functional Nokdujukr using RSM, mulberry leaf powder (MLP:X1) and mulberry fruit powder (MLF:X2) were set as independent variables, and pH (Y1), sweetness (Y2), viscosity (Y3), L (Y4), a (Y5), b (Y6), color (Y7), flavor (Y8), taste (Y9), overall quality (Y10), TPC (Y11), and DPPH radical scavenging ability ($IC_{50}$)(Y12) were set as dependent variables. The optimum mixing ratio of MLP and MLF was determined to be 3.88 g of MLP and 6 g of MLF. The values of color, flavor, taste, overall quality, TPC, and DPPH radical scavenging ability ($IC_{50}$) of optimized Nokdujuk were 5.20, 5.85, 6.00, 6.22, 330.99 mg TAE/g and 650.10 g/mL, respectively. In conclusion, this study has led to the development of an improved version of Nokdujuk that has antioxidative properties and good sensory evaluation and, will likely serve as a functional meal replacement for the busy modern world.

• Korean journal of food and cookery science
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• v.25 no.3
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• pp.275-282
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• 2009

This study investigated the quality characteristics of Pongnip Injeulmi samples according to different mulberry leaf powder(MLP) contents. The moisture levels of the samples ranged from 47.43 to 49.16%, with the 0% MLP sample presenting the highest moisture level. The amounts of crude protein, crude fat, and crude ash in samples were in ranges of 3.82${\sim}$5.01%, 0.05${\sim}$0.2%, and 0.65${\sim}$1.62%, respectively, and the values increased with increasing MLP content. Color L and b values decreased, while the a-value increased, with increasing MLP content. The 0% sample showed the highest gelatinization temperature of 63.4$^{\circ}$C, and the viscosity decreased with increasing MLP content. Texture and hardness also decreased with increasing MLP content, however, over 3 days storage, they increased in all samples. Finally, in the sensory tests, the 6% MLP sample received the highest scores for color, flavor, sweetness, texture and overall acceptability.

• Nutritional Sciences
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• v.9 no.2
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• pp.97-105
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• 2006

Beans are well known to be high-protein diets. Bean seeds contain arginine, lysine, or glycine-rich proteins which are effective to maintain lower glucose levels. In this study, the synergistic effect of fermented small soybean (Chounggukjang) and mulberry leaf on metabolism and hexokinase activity was investigated in streptozotocin (STZ)-induced diabetic rats. We divided 8 groups as follows: non-diabetic rat group fed with only water diet (NC: control), and STZ-induced diabetic rat groups fed with water (DC), fermented Rhynchosia Nulubilis (Bbc), fermented Glycine max Merr (Ybc), Bbc and YBc (BYbc), mulberry leaf and Bbc (MBbc), mulberry leaf and Ybc (MYbc), or the mulberry leaf, Bbc, and Ybc (MBYbc). Diabetes mellitus was induced in rats by subcutaneous STZ administration (70 mg/kg of body weight). All diet groups were fed with Chounggukjang in a powder form. Three ml of Chounggukjang solution (0.75 mg per gram of body weight) dissolved in distilled water was orally administered to all rat groups after STZ administration except for NC rat group. In groups fed with fermented soybeans, the body weight (increased), food efficiency ratio (FER) (increased), glucose level (decreased) and hexokinase (HK) activity (increased) significantly differed to NC. Among them, particularly in the groups fed with both fermented soybeans and mulberry leaf, kidney weight significantly decreased, whereas HK activity significantly increased compared to DC. These results suggest that Chounggukjang of both fermented soybeans and mulberry leaf is potentially used as an effective functional food to prevent diabetes complications.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.977-986
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• 2007

This study was conducted to evaluate the mechanical (texture and color) and sensory characteristics of mulberry leaf sulgi (MLS) and lotus leaf sulgi (LLS) that contained different ratios of ingredients. MLS and LLS with final concentrations of 0%, 1%, 3% and 5% of powdered mulberry and lotus leaf respectively, were prepared. The texture characteristics (hardness, adhesiveness, springiness, cohesiveness, gumminess, chewiness), color values (lightness, redness, yellowness), and sensory characteristics (color, flavor, moistness, taste, brittleness, chewiness and after-taste) of the different sulgis were then measured and compared. With the exception of gumminess and chewiness, the texture characteristics of 0% MLS, 1% MLS and 3% MLS were not significantly different. The sensory characteristics of 0% MLS had the highest scores, whereas those of 5% MLS were the lowest for all factors except for brittleness. However, with the exception of chewiness, the scores obtained from 0% and 1 % MLS did not differ significantly. In addition, 1% MLS and 3% MLS were not significantly different from each other. Furthermore, the texture characteristics of 0% LLS and 1 % LLS were not different significantly, although the characteristics of 1% LLS were significantly different from those of 3% and 5% LLS when springiness, cohesiveness, and chewiness were considered. Additionally, the sensory characteristics of 0% LLS and 1% LLS were not significantly different, with the exception of brittleness, and the characteristics of 1% LLS and 3% LLS were not significantly different, with the exception of taste and after-taste.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.1
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• pp.24-30
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• 2016

1-Deoxynojirimycin (DNJ) have been extensively investigated for their α-glucosidase inhibitor on postprandial hyperglycemia, and applied in nutraceuticals and medicine for preventing or delaying progression of type 2 diabetes. However, the amount of DNJ in mulberry leaves is low (about 0.1%), therefore, more effective extraction method is needed. This study was performed to develop microbial DNJ for biological methods of DNJ as an alternative to the chemical methods. In this study, we obtained evidence for Bacillus subtilis that produce DNJ in large quantities by high performance liquid chromatography. Inhibition of α-glucosidase activity was determined to DNJ production or non-production. Investigation of the effect of mulberry leaves powder concentration (1~5%), using the DNJ high-production bacteria, provided evidence for microbial mass production of DNJ. When the 4% mulberry leaf powder for 9 days was used, the α-glucosidase inhibitory activity was over the 85%. Also, the results presented in this study confirm DNJ yield's increasement in microbes using the various of nutrients and provide insight of ways to improve DNJ yields in microorganisms.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.48-55
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• 2015

1-Deoxynojirimycin (DNJ) has been extensively investigated for its applications as an a-glucosidase inhibitor in postprandial hyperglycemia, and has been applied to nutraceuticals and medicines to prevent or delay the progression of type 2 diabetes. However, the amount of DNJ in mulberry leaves is low (approximately 0.1%), therefore, a more effective extraction method is needed. In this study, microbial DNJ production was developed as an alternative to chemical methods. We identified fermented sericultural products and bacteria that produce DNJ in large quantities using high performance liquid chromatography and thin layer chromatography. The inhibition of a-glucosidase activity was examined with respect to DNJ production or non-production. Crude DNJ from the isolated strains exhibited greater than 70% a-glucosidase activity. An investigation of the effect of mulberry leaf powder concentration (1~5%), using high DNJ producing bacteria, provided evidence for microbial mass production of DNJ.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1081-1090
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• 2017

The purpose of this study was to develop a functional porridge prepared with mulberry leaf and mulberry fruit powder, which can ameliorate hypertension. The experiment was designed according to the central composite design. For optimization of the mixture ratio of mulberry leaf powder (MLP) and mulberry fruit powder (MFP), the independent variables were defined as MLP (X1) and MFP (X2) and the dependent variables were defined as K (Y1), Na (Y2), ${\gamma}$-aminobutyric acid (GABA) (Y3), cyanidin-3-glycoside (C3G) (Y4), rutin (Y5), and flavonoid (Y6). The optimal MLP to MFP mixture ratio according to the response surface method were 5.41 g of MLP and 2.65 g of MFP. The amounts of K, Na, GABA, C3G, rutin, and flavonoid in the optimal MLP and MFP mixture were 1,844.22 mg/100 g, 52.74 mg/100 g, 139.98 mg/100 g, 1,134.89 mg/100 g, 101.56 mg/100 g, and 201.28 mg/100 g, respectively. The amounts of Ca, K, Mg, and Na in the functional porridge at this optimal point were 27.66 mg/100 g, 131.32 mg/100 g, 19.57 mg/100 g, and 3.59 mg/100 g, respectively. Overall, this functional porridge can help reduce hypertension.