• Food Science and Preservation
• /
• v.31 no.3
• /
• pp.394-407
• /
• 2024

The poultry industry faces disposal difficulty in waste, but recent advancements in material science and sustainability have enabled the innovative transformation of waste into valuable resources. In this study, eggshell (EC) was added as a bio-filler to gum Arabic (GA) to fabricate a GA-EC bio-composite film. Bio-composites containing 0.5 g (GA-EC_0.5) and 1.0 g (GA-EC_1.0) EC dispersed in 30 mL of 15% GA solution were fabricated and characterized using standard analytical techniques. The GA-EC_0.5 composites showed significantly higher moisture content, transparency, water solubility, and water vapor permeability but lower tensile strength and thermal stability than GA-EC_1.0. Following a post-harvest wrapping of tomato fruits with the GA-EC composite films and storage at 25±2℃ for 20 days, significant (p>0.05) reductions in weight loss, pH, lycopene content, and activities of polyphenol oxidase and pectin methylesterase compared to unwrapped fruits were recorded. Adding EC to GA has enabled the fabrication of composite films with improved mechanical, barrier, and thermal properties with potential application in the post-harvest storage of tomato fruits.

• Food Science and Preservation
• /
• v.31 no.3
• /
• pp.462-473
• /
• 2024

The anti-inflammatory effect of beluga lentil extract (BLE) and its underlying mechanisms were investigated in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Treatment with BLE significantly decreased nitric oxide (NO) production and protein and mRNA expressions of inducible NO synthase (iNOS) in LPS-treated RAW 264.7 cells. Down-regulation of this inflammatory gene expression was not associated with NF-κB/MAPK signaling pathways, and further mechanistic studies demonstrated that BLE decreased LPS-induced iNOS expression through upregulation of the nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated heme oxygenase-1 (HO-1) expression. These results suggest that beluga lentil represent a potential source of natural anti-inflammatory agents, and further studies will be necessary to determine its anti-inflammatory effects in vivo.

• Journal of the Korean Wood Science and Technology
• /
• v.32 no.2
• /
• pp.19-25
• /
• 2004

This study was carried out to investigate a radial distribution of moisture contents (MCs) within a log cross section (LC) during oven-drying of 3 mm-thick circumferential slices cut from several domestic softwoods LCs.For Korean red pine, drying rate of sapwood slices during oven-drying represented much higher values than that of heartwood slices, and so sapwood with higher green MC early reached below fiber saturation point (FSP) rather than heartwood did. However, this distribution of moistures did not last for long duration. For Japanese larch, green MC of sapwood was approximately three times higher than that of heartwood. This similar distribution in MC was lasted until about 20% average MC. The MC was around uniform throughout the sapwood of Ginkgo when green and during oven-drying, although it was somewhat fluctuated. For Japanese cedar, the heartwood with so low moistures around FSP would begin to shrink from the beginning stage of drying, but the sapwood above hygroscopic MC prevents the heartwood from shrinking, and consequently, the heartwood or the transition wood goes into tension stress. The results for Japanese cypress showed that the green MCs of the sapwoods were much lower than those for heartwoods, and then this trend was continued until about 20% in average MC. For Chinese thuja, the green MCs of sapwoods were about 2 times as high as those of heartwood, but this along the radial gradient in MC rapidly became gentle during oven-drying.

• Journal of Welding and Joining
• /
• v.30 no.1
• /
• pp.64-71
• /
• 2012

The characteristics of high heat input (342kJ/cm) EG (Electro Gas Arc) welded joint of EH36-TM steel has been investigated. The weld metal microstructure consisted of fine acicular ferrite (AF), a little volume of polygonal ferrite (PF) and grain boundary ferrite (GBF). Charpy impact test results of the weld metal and heat affected zone (HAZ) met the requirement of classification rule (Min. 34J at $-20^{\circ}C$). In order to evaluate the relationship between the impact toughness property and the grain size of HAZ, the austenite grain size of HAZ was measured. The prior austenite grain size in Fusion line (F.L+0.1 mm) was about $350{\mu}m$. The grain size in F.L+1.5 mm was measured to be less than $30{\mu}m$ and this region was identified as being included in FGHAZ(Fine Grain HAZ). It is seen that as the austenite grain size decreases, the size of GBF, FSP (Ferrite Side Plate) become smaller and the impact toughness of HAZ increases. Therefore, the CGHAZ was considered to be area up to 1.3mm away from the fusion line. Results of TEM replica analysis for a welded joint implied that very small size ($0.8\sim1.2{\mu}m$) oxygen inclusions played a role of forming fine acicular ferrite in the weld metal. A large amount of (Ti, Mn, Al)xOy oxygen inclusions dispersed, and oxides density was measured to be 4,600-5,300 (ea/mm2). During the welding thermal cycle, the area near a fusion line was reheated to temperature exceeding $1400^{\circ}C$. However, the nitrides and carbides were not completely dissolved near the fusion line because of rapid heating and cooling rate. Instead, they might grow during the cooling process. TiC precipitates of about 50 ~ 100nm size dispersed near the fusion line.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.9
• /
• pp.92-100
• /
• 2017

The Helicopter MRA Control Rod System has the important function of controlling the speed, height, and direction of helicoptersby adjusting the main rotor disc. However, the ingress of water into the inner control rod can cause ice damage in the rod during winter operation and also corrosion;these defects need to be rectified. The water flowed into the control rod through the upper side space, and the rod was cracked during icing expansion occurring at low temperature. The corrosion occurred due to the lack of coating process during the manufacturing process. To resolve these problems, the upper rod was sealed to prevent water inflow and a coating process was added to prevent corrosion. These solutions were verified by awaterproof test and a salt fog test. The phenomena, causes and measures were reviewed and the methods of improvement were established and proven. This proposed technology to prevent water infiltration and corrosion will contribute to the safety of rotary wing aircraft.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.9
• /
• pp.1285-1293
• /
• 2005

The present study was conducted to evaluate and compare the effects of various animal and plant protein sources on piglet' performance, digestibility of amino acids and gut morphology in weaned pigs until 28 days after weaning. The plant protein sources used were soybean meal (SBM), fermented soy protein (FSP), rice protein concentrate (RPC); and animal protein sources tested were, whey protein concentrate (WPC) and fishmeal (FM). Iso-proteinous (21%) diets were formulated and lysine (1.55%) content was similar in all the diets. The level of each protein source added was 6% by replacing SBM to the same extent from the control diet containing 15% SBM. The ADG was higher (p<0.05) in the groups fed animal proteins as compared with plant proteins at all the levels of measurement, except during 15-28 days. The highest ADG was noted in WPC and FM fed diets and lowest in SBM fed diet. The feed intake was higher in animal protein fed groups than plant proteins at all phases, but the feed:gain ratio was not affected by protein sources except during overall (0 to 14 day) measurement which was improved (p<0.05) in animal protein fed diets compared to plant protein sources. The digestibilities of gross energy, dry matter and crude protein were higher in animal protein fed groups than for plant protein fed sources. The apparent ileal digestibilities of essential amino acids like Leu, Thr, and Met were significantly (p<0.05) higher in animal proteins fed animals as compared with plant protein fed animals. But the apparent fecal digestibilities of essential amino acids like Arg and Ile were significantly higher (p<0.05) in plant protein diets than animal protein sources. The villous structure studied by scanning electron microscope were prominent, straight finger-like, although shortened and densely located in FM fed group as compared with others. The lactic acid bacteria and C. perfringens counts were higher in caecal contents of pigs fed plant proteins than the animal proteins. Overall, it could be concluded that animal protein sources in the present study showed better effects on growth performance, nutrient digestibility and gut morphology than plant protein sources.

• Food Science and Preservation
• /
• v.31 no.1
• /
• pp.126-137
• /
• 2024

In this study, zinc oxide nanoparticles (ZnONPs) were synthesized using three distinct zinc salts: zinc acetate, zinc chloride, and zinc nitrate. These ZnONPs were subsequently utilized in the fabrication of carrageenan-ZnONPs (Car-ZnONPs) composite films. The study assessed influence of the various ZnONPs on the morphological, water vapor barrier, color, optical, and antimicrobial properties of the Car-ZnONPs composite films. The surface morphology and UV-blocking attributes of the composite films were affected by the type of ZnONPs used, but their surface color, transparency, and chemical structure remained unaltered. The composite film's thickness and elongation at break (EB) significantly increased, while the tensile strength significantly decreased. In contrast, film's elastic modulus (EM) and water vapor permeability coefficient (WVP) showed no significant difference. All the composite films with added ZnONPs demonstrated potent antibacterial activity against Escherichia coli O157:H7 and Listeria monocytogenes . Among the carrageenan-based composite films, Car-ZnONPs^ZC showed the highest antibacterial and UV-blocking properties, and its elongation at break was significantly higher than that of the pure carrageenan films. This suggests that ZnONPs composite films have the potential to be used as an active packaging film, preserve the safety of the packaged food and extend shelf life.

• Food Science and Preservation
• /
• v.31 no.1
• /
• pp.138-148
• /
• 2024

The production of poly-γ-glutamic acid (γ-PGA) and γ-aminobutyric acid (GABA) was optimized by serial fermentation of Dendropanax morbiferus extract (DME) using Bacillus subtilis HA and Lactobacillus plantarum KS2020. The 1st alkaline fermentation was performed on 60% DME including 2% glucose and 10% monosodium ʟ-glutamate (MSG) as a precursor. The 1^st fermented DME had 57 mg% tyrosine. Consequently, the 2^nd lactic acid fermentation for 5 days increased the tyrosine content of 106 mg%. The mucilage containing γ-PGA showed a high content of 3.50% on the first day of alkaline fermentation and then increased to 4.10% after 2 days. The precursor (MSG) remaining in the 1^st fermented DME was efficiently converted to GABA by the 2^nd lactic acid fermentation in the presence of 5% skim milk, 1.5% glucose and 0.5% yeast extract, resulting in the production of 18.29 mg/mL GABA. The viable cells of lactic acid bacteria increased and indicated 9.49 log CFU/mL on the fermentation for 5 days, and the acidity of co-fermented DME indicated the highest value of 1.55%. Conclusively, the serial fermented DME has multi-functional ingredients containing γ-PGA, GABA, peptides and probiotics.

• Food Science and Preservation
• /
• v.31 no.1
• /
• pp.161-172
• /
• 2024

This study investigated the anti-obesity effects of lactic acid bacteria ferments cultured in industrial medium with ethanol extract of ramie leaf (Boehmeria nivea L.). On the 4th day of fermentation, the maximum live cell counts were 8.75-8.85 log CFU/mL, pH was 3.74-3.79, and total acidity was 2.07-2.19%. The fermentation of lactic acid bacteria on the fourth day resulted in the amount of lactic acid reaching 1,676.03-1,910.12 mg%. The lipase inhibitory activities of Lactiplantibacillus plantarum (L. plantarum) JBLAB0101 (FRLPLA) and Lactobacillus rhamnosus GG (LGG, (FRLLGG)) ferments were 30.10%, and 25.63%, respectively, at a concentration of 0.5 mg/mL. The lipid accumulation, leptin production, PPAR-γ and SREBP-1c mRNA levels were decreased to 37.54%, 54.64%, 24.18%, and 31.32%, respectively, at 200 ㎍/mL concentration of FRLPLA. These results suggest that anti-obesity effect could be increased by lactic acid bacteria in industrial medium with extract of ramie leaf.

• Food Science and Preservation
• /
• v.31 no.2
• /
• pp.307-314
• /
• 2024

Broussonetia kazinoki twig extract (BKT) is recognized for its antioxidant and anti-cancer effects and natural whitening properties. So, it is used as a raw material for cosmetics. B. kazinoki twig is also an edible raw material. B. kazinoki has been used in Asia for paper production and oriental medicine, has anti-diabetic effects, and contains various flavonoids and alkaloids. In this study, to evaluate the efficacy of BKT on allergic skin inflammatory responses, we investigated its effects on factors related to skin inflammation in HaCaT keratinocytes and allergic responses in RBL-2H3 cells. There was no cytotoxicity of the 70% ethanol extract against HaCaT and RBL-2H3 cells. In HaCaT cells, stimulation with tumor necrosis factor-alpha (TNF-𝛼) and interferon-gamma (IFN-𝛾) increased the production of several chemokines, including thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), and regulated on activation, normal T cell expressed and secreted (RANTES). However, it was observed that this elevation was notably mitigated in a concentration-dependent manner upon treatment with BKT. Furthermore, BKT treatment demonstrated a significant reduction of 𝛽-hexosaminidase and inflammatory cytokines TNF-𝛼 and IL-4 in IgE-sensitized RBL-2H3 cells. Thus, it is expected that BKT can be used as a natural cosmetic and food ingredient that effectively suppresses allergic inflammatory reactions.