• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.647-652
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• 2004

Thermophilic microorganisms capable of producing chitinase enzymes were screened from samples collected from several crater and geothermal areas. The chitinolytic microorganisms were grown in a selective medium containing colloidal chitin. The Bacillus K29-14 isolate was found to exhibit the highest chitinase and chitin deacetylase activities. When grown in a chitin-containing medium, the isolate produced extracellular chitinase after 24 h of incubation. The optimum temperature and pH for the chitinase were $55^\circ{C}$ and pH 7, respectively, while those for the chitin deacetylase were $55^\circ{C}$ and pH 8, respectively. The thermostable chitinase and chitin deacetylase also retained 80- 90% of their activity after incubation for 5 h at $70^\circ{C}$. The divalent cations $CoCl_2\;and\;NiCl_2$, increased the chitinase activity, while $ZnCl_2$, inhibited the enzyme. The chitin deacetylase was also activated by the presence of $MgCl_2$ and inhibited by $MnCl_2,\;NiCl_2,\;and\;CaCl_2$. A zymogram analysis revealed several forms of chitinase, with a 67 kDa form being the major enzyme.

• 보건행정학회지
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• 제11권1호
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• pp.37-61
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• 2001

In the course of this research, we developed FRIS(Food Replica Information System), which calculates calories and nutrient values of foods in a very simple and interesting manner, and experienced of application to some communities. We expect that individuals will have opportunities to raise their consciousness of food, nutrients, and healthy living by participating in FRIS. 154 kinds of commonly consumed Korean foods were selected and one serving sized food replicas, having the same shapes, size, and color as the real foods, were constructed with attached bar code labels. An application program with food replicas and bar code was also developed in order to provide information on calories and nutrient values for people's meals or selected foods based on survey results of housewives' requirements related to foods and nutrients. FRIS should be a basic tool in nutrition education and consultation. Its applicability would vary according to the nutritionist's flexibility and contents of developed application programs. Technical stability should be strengthened and more useful contents of application prograln be added to spread the use of the system. Additionally, in future research, more delicate models should be developed and an analytical method should be applied to examine the effects of FRIS to individual behavioral changes in their eating habits.

• Food Science and Biotechnology
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• 제15권1호
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• pp.77-81
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• 2006

The dextransucrase activity of microorganisms which were identified as contributing to the fermentation of jeungpyeon made with yeast was measured. The dextran generated during fermentation was quantified and the viscosity changes were measured. The mechanism of network structure formation was clarified by observing the inside of the network structure over the fermentation periods ranging from 1 to 7 hr using scanning electron microscopy (SEM). The pH of jeungpyeon batter decreased significantly as the fermentation proceeded, whereas the viscosity increased. The identified lactic acid bacteria (LAB) were Leuconostoc mesenteroides subsp. mesenteroides, Pediococcus pentosaceus, Tetragenococcus halophilus, and Leuconostoc mesenteroides subsp. dextranicum. The yeast was identified as Saccharomyces cerevisiae A/Tor. Pretorien. The dextransucrase extracted from those microorganisms showed high activity. On the other hand, the amount of dextran generated from the batter increased significantly beyond 2 hr of fermentation, and the viscosity increment showed a similar trend. The SEM photos showed that the most homogeneous fine network structure was observed in the batter fermented for 2 hr. Therefore, we assumed that the dextran that was generated by microorganisms during fermentation interacted with the components of the batter to increase the stability of the network structure.

• 한국식생활문화학회지
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• 제30권1호
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• pp.118-128
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• 2015

This study was performed to analyze health problems in older adults in a comprehensive manner, including usual living habits, nutritional status, and society psychological factors. Research was conducted by a structured questionnaire by interviews with a test group of 316 people over the age of 65 from April 2012 to August 2012. Elderly people's dietary intake was assessed using NSI (Nutrition Screening Initiative) by the 24-hour retrospective method, and elderly people's feeling of helplessness and sense of belonging were assessed using the measuring device. Material analysis, descriptive statistics, and regression analysis were performed using SPSS. Elderly people with increased age showed higher chances of being in the high-risk and undernourished group. Elderly with high NSI showed low intake of fat, protein, fibrin, vitamin C, E, $B_1$, $B_2$, Niacin, K, Fe, Zn, and Cu than those with low NSI. Findings from this comparative analysis indicate that elderly with better nutritional status showed a lower feeling of helplessness than those with poor nutritional status. Overall, elderly people consumed a b road variety of foods, and social emotional stability of elderly people increased at optimal dietary levels.

• 한국식품조리과학회지
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• 제28권4호
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• pp.431-441
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• 2012

The purpose of this study was to determine the optimal mixing conditions, storage, and irradiation characteristics by two different amounts of cabbage powder and water in bread prepared with cabbage powder. A significant increase or decrease in dough pH (p<0.01), sweetness (p<0.05), water content (p<0.001), L-value (p<0.01), a-value (p<0.001), b-value (p<0.001), hardness (p<0.05), springiness, and chewiness (p<0.05) was observed. Sensory measurements showed a significant improvement in appearance, flavor, color, taste (p<0.05), texture, moisture (p<0.01), and overall quality (p<0.05). As a result, the optimum formulation obtained by numerical and graphical methods was 37.04 g cabbage powder and 385.3 g water. The optimized and control breads were irradiated and their DPPH radical scavenging activities and total plate counts were evaluated over 6 days. The result showed the antioxidant and antibiotic action of the bread with cabbage powder.

• 한국축산식품학회지
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• 제39권5호
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• pp.742-755
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• 2019

Cacao bean husk (Theobroma cacao L.) contains a high level of dietary fiber and therefore can be used as raw material in food processing. The objective of the present study was to measure the physicochemical properties and sensory traits of emulsion-type pork sausages with various levels of cacao bean husk powder (0.25%, 0.5%, 0.75%, 1%, and 2%). The moisture content in cooked sausages increased as the level of cacao bean husk power increased, whereas the protein content decreased (p<0.05). With respect to color, as the level of cacao bean husk power increased, there was a decrease in lightness and yellowness, but there was a considerable increase in redness (p<0.05). Cacao bean husk powder exhibited a positive effect on emulsion stability and apparent viscosity. In the sensory evaluation, increased level of cacao bean husk increased flavor acceptability; the 0.75% and 1% treatment groups showed significantly high overall acceptability (p<0.05). The thiobarbituric acid reactive species content of cooked sausages indicated that with the addition of cacao bean husk powder significantly inhibited lipid oxidation in the sausages during refrigerated storage (p<0.05). Overall, the findings of the present study suggest that adding 0.75% and 1% cacao bean husk powder as a natural ingredient in sausages can help develop meat products with excellent qualities.

• Journal of Applied Biological Chemistry
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• 제62권1호
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• pp.101-107
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• 2019

The objectives of this study were to evaluate the anti-aging effects and investigate the effect of simulated gastrointestinal (GI) digestion on the anti-aging properties and intestinal permeation of the potential fish collagen hydrolysates (FCH). Therefore, procollagen synthesis, matrix metalloproteinase-1 (MMP-1) production, and Caco-2 cell permeability were analyzed before and after in vitro digestion for FCHs, low-molecular weight fractions (<1 kDa), and high molecular weight fractions (>1 kDa). After being subjected to GI digestion, the level of MMP-1 inhibition was maintained, although the procollagen production was significantly (>20%) lower with all samples. Also, the digested FCHs and their <1 kDa fraction yielded 9.1 and 13.8% increased peptide transport, respectively, compared to undigested samples. Based on the effective intestinal permeation and high digestive enzyme stability, the <1 kDa fraction of FCHs is a potential bioactive material suitable for anti-aging applications in the food and cosmetics industries.

• Nutrition Research and Practice
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• 제17권4호
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• pp.597-615
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• 2023

Healthy aging can be defined as an extended lifespan and health span. Nutrition has been regarded as an important factor in healthy aging, because nutrients, bioactive food components, and diets have demonstrated beneficial effects on aging hallmarks such as oxidative stress, mitochondrial function, apoptosis and autophagy, genomic stability, and immune function. Nutrition also plays a role in epigenetic regulation of gene expression, and DNA methylation is the most extensively investigated epigenetic phenomenon in aging. Interestingly, age-associated DNA methylation can be modulated by one-carbon metabolism or inhibition of DNA methyltransferases. One-carbon metabolism ultimately controls the balance between the universal methyl donor S-adenosylmethionine and the methyltransferase inhibitor S-adenosylhomocysteine. Water-soluble B-vitamins such as folate, vitamin B6, and vitamin B12 serve as coenzymes for multiple steps in one-carbon metabolism, whereas methionine, choline, betaine, and serine act as methyl donors. Thus, these one-carbon nutrients can modify age-associated DNA methylation and subsequently alter the age-associated physiologic and pathologic processes. We cannot elude aging per se but we may at least change age-associated DNA methylation, which could mitigate age-associated diseases and disorders.

• 식품보건융합연구
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• 제10권2호
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• pp.13-17
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• 2024

Oxygen is necessary to sustain life, but reactive oxygen species (ROS) produced by oxygen metabolism can cause mutations and toxicity. ROS can damage cellular macromolecules, leading to oxidative stress, which can accelerate cell death and aging. ROS generated in food affect the taste, color, and aroma of food, and high levels of ROS in meat can cause spoilage. Superoxide dismutase (SOD) plays an important role in scavenging ROS in food and reducing their toxicity to organisms. SOD exerts its antioxidant effect by catalyzing the breakdown of O₂-• to H₂O₂. As a natural antioxidant, SOD has the ability to regenerate and maintain its activity over a long period of time without depletion, unlike chemical antioxidants that may have side effects or stability issues. This antioxidant effect of SOD has great potential in a variety of industries, and in the food industry it can be utilized to improve product quality and provide safe and healthy products to consumers. By disrupting the SOD2 and SOD3 genes in Candida albicans, we studied the effects of SOD2 and SOD3 genes on the antioxidant system, suggesting its potential as a natural antioxidant.

• 한국식품영양학회지
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• 제22권1호
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• pp.150-157
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• 2009

The purpose of this study was to analyze the anthocyanin contents of black soybean crude extracts derived using a countercurrent system and to compare the effects of stabilizers(${\beta}-cyclodextrin$, maltodextrin) and sugars(sucrose, maltose) on the color deterioration of the anthocyanin. When the extraction process was kept at 100$^{\circ}C$ for 120$\sim$180 min, only C3G (cyanidin-3-glucoside) was detected in the water extract. The C3G contents in the water extracts acquired at 8$^{\circ}C$, 60$^{\circ}C$, and 80$^{\circ}C$ were 2.38 ppm, 1.73 ppm, and 1.73 ppm, respectively. Sucrose and maltose retarded color deterioration of the crude pigment extract by the countercurrent method with methanol. Finally, the additions of maltodextrin or ${\beta}-cyclodextrin$ did not retard thermal color deterioration of the black soybean crude pigment extract.