• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.98-133
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• 1987

The mechanical and rheological properties of agricultural materials are important for engineering design and analysis of their mechanical harvesting, handling, transporting and processing systems. Agricultural materials, which composed of structural members and fluids do not react in a purely elastic manner, and their response when subjected to stress and strain is a combination of elastic and viscous behavior so called viscoelastic behavior. Many researchers have conducted studies on the mechanical and rheological properties of the various agricultural products, but a few researcher has studied those properties of rice plant, and also those data are available only for foreign varieties of rice plant. This study are conducted to experimentally determine the mechanical and the rheological properties such as axial compressive strength, tensile strength, bending and shear strength, stress relaxation and creep behavior of rice stems, and grain detachment strength. The rheological models for the rice stem were developed from the test data. The shearing characteristics were examined at some different levels of portion, cross-sectional area, moisture content of rice stem and shearing angle. The results obtained from this study were summarized as follows 1. The mechanical properties of the stems of the J aponica types were greater than those of the Indica ${\times}$ Japonica hybrid in compression, tension, bendingand shearing. 2. The mean value of the compressive force was 80.5 N in the Japonica types and 55.5 N in the Indica ${\times}$ Japonica hybrid which was about 70 percent to that of the Japonica types, and then the value increased progressively at the lower portion of the stems generally. 3. The average tensile force was about 226.6 N in the Japonica types and 123.6 N in the Indica ${\times}$ Japonica hybrid which was about 55 percent to that of the Japonica types. 4. The bending moment was $0.19N{\cdot}m$ in the Japonica types and $0.13N{\cdot}m$ in the Indica ${\times}$ Japonica hybrid which was 68 percent to that of the Japonica types and the bending strength was 7.7 MPa in the Japonica types and 6.5 MPa in the Indica ${\times}$ Japonica hybrid respectively. 5. The shearing force was 141.1 N in Jinju, the Japonica type and 101.4 N in Taebaeg, the Indica ${\times}$ Japonica hybrid which was 72 percent to that of Jinju, and the shearing strength of Taebaeg was 63 percent to that of Jinju. 6. The shearing force and the shearing energy along the stem portion in Jinju increased progressively together at the lower portions, meanwhile in Taebaeg the shearing force showed the maximum value at the intermediate portion and the shearing energy was the greatest at the portion of 21 cm from the ground level, and also the shearing strength and the shearing energy per unit cross-sectional area of the stem were the greater values at the intermediate portion than at any other portions. 7. The shearing force and the shearing energy increased with increase of the cross-sectional area of the rice stem and with decrease of the shearing angie from $90^{\circ}$ to $50^{\circ}$. 8. The shearing forces showed the minimum values of 110 N at Jinju and of 60 N at Taebaeg, the shearing energy at the moisture content decreased about 15 percent point from initial moisture content showed value of 50 mJ in Jinju and of 30 mJ in Taebaeg, respectively. 9. The stress relaxation behavior could be described by the generalized Maxwell model and also the compression creep behavior by Burger's model, respectively in the rice stem. 10. With increase of loading rate, the stress relaxation intensity increased, meanwhile the relaxation time and residual stress decreased. 11. In the compression creep test, the logarithmic creep occured at the stress less than 2.0 MPa and the steady-state creep at the stress larger than 2.0 MPa. 12. The stress level had not a significant effect on the relaxation time, while the relaxation intensity and residual stress increased with increase of the stress level. 13. In the compression creep test of the rice stem, the instantaneous elastic modulus of Burger's model showed the range of 60 to 80 MPa and the viscosities of the free dashpot were very large numerical value which was well explained that the rice stem was viscoelastic material. 14. The tensile detachment forces were about 1.7 to 2.3 N in the Japonica types while about 1.0 to 1.3 N in Indica ${\times}$ Japonica hybrid corresponding to 58 percent of Japonica types, and the bending detachment forces were about 0.6 to 1.1 N corresponding to 30 to 50 percent of the tensile detachment forces, and the bending detachment of the Indica ${\times}$ Japonica hybrid was 0.1 to 0.3 N which was 7 to 21 percent of Japonica types. 15. The detachment force of the lower portion was little bigger than that of the upper portion in a penicle and was not significantly affected by the harvesting period from September 28 to October 20. 16. The tensile and bending detachment forces decreased with decrease of the moisture content from 23 to 13 percent (w.b.) by the natural drying, and the decreasing rate of detachment forces along the moisture content was the greater in the bending detachment force than the tensile detachment force.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1202-1207
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• 2016

This study investigated the anti-obesity effects of Eriobotrya japonica leaves extract (EJE) in a high-fat diet-induced obese mice model. For the analysis, 40 mice were randomly divided into five groups: normal diet (ND), high-fat diet group (HD), high-fat diet containing EJE 100 mg/kg b.w. (EJE-L), 500 mg/kg b.w. (EJE-H), and Garcinia cambogia extract 100 mg/kg b.w. in each AIN 93G supplement for 8 weeks as positive control. During the study period, food intake and body weight were measured separately. Body weight, serum triglyceride level, and total cholesterol levels of the EJE group were significantly lower than those of the HD and ND. Moreover, mice fed an EJE-containing high-fat diet showed decreased leptin levels compared with high-fat diet-induced obese mice. These results suggest that EJE has potential as an anti-obesity agent by reducing body weight and improving levels of triglycerides, total cholesterol, low density lipoprotein-cholesterol, and leptin in serum.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.271.2-271.2
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• 2001

• Biomolecules & Therapeutics
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• v.18 no.2
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• pp.197-204
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• 2010

To establish the anti-inflammatory activity of the total flavonoid fraction of the root barks of Broussonetia papyrifera (EBP) and a new formula, the ethanol extract of the root barks of B. papyrifera was fractionated with ethylacetate, yielding the hydrophobic prenylated flavonoid-enriched fraction. EBP and the ethanol extract of the whole Lonicera japonica (ELJ) plant were then mixed at a ratio of 1:1 (w/w) to give a new preparation (BL) in the hope of obtaining an optimal formula with a higher anti-inflammatory activity. Evaluation of the effects of these preparations on A23187-treated rat basophilic leukemia (RBL-1) cells revealed that EBP potently inhibited 5-lipoxygenase (5-LOX), while ELJ showed weak inhibition. Additionally, the mixture (BL) clearly showed stronger inhibitory effects against 5-LOX than either preparation alone. These preparations also inhibited cyclooxygenase-2-catalyzed $PGE_2$ and inducible nitric oxide (NO) synthase-catalyzed NO production by lipopolysaccharide-treated RAW 264.7 cells. When tested against arachidonic acid-induced mouse ear edema, EBP showed strong inhibitory activity at doses of 5-200 mg/kg when administered orally, but BL had obviously stronger inhibitory effects. When tested against ${\lambda}$-carrageenan-induced paw edema in mice, BL showed a potent and synergistic anti-inflammatory effect. In addition, in the acetic acid-induced writhing test, BL was found to have strong analgesic activity at 50-400 mg/kg. Taken together, these results indicate that each of these preparations exert anti-inflammatory activity in vitro and in vivo. In particular, BL showed stronger anti-inflammatory activity than EBP, and these anti-inflammatory effects were partially related to the inhibition of eicosanoid and NO production. BL may be useful for the treatment of human inflammatory disorders.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.200-206
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• 2005

This study was performed to develop a functional stirred yoghurt prepared from skim milk added with loquat(Eriobotrya japonica Lindley). Skim milk containing $15\%$ loquat extract was fermented by the mixed strains of Streptococcus thermophilus and Lactobacillus acidophilus, and then loquat flesh and oligosaccharide were added to the yoghurt base. Sensory scores of the stirred yoghurt containing $15\%$ loquat flesh and $20\%$ oligosaccharide were higher than other groups in sweet taste, sour taste and overall acceptability. When the levels of oligosaccharide of the stirred yoghurts added with $15\%$ loquat flesh were increased, the L value(brightness) and a value (redness) of the stirred yoghurt decreased, but the b value(yellowness) increased. The hardness, springiness, cohesiveness, gumminess and resilience of the $15\%$ loquat flesh stirred yoghurt added with $20\%$ oligosaccharide were higher than others.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.107-110
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• 2021

The goal of this study was to investigate moisture sorption characteristics of Lactobacillus brevis-fermented sea tangle Saccharina japonica, Mekabu fucoidan, and these mixture powders. Moisture sorption isotherms of powders were determined at 37℃ using the static gravimetric technique in a water activity (aw) range of 0.11-0.93. Equilibrium moisture content (Xeq) values of the fermented sea tangle powder were almost 3 times when aw<0.7 and increased upto almost 4 times when aw<0.9 higher than mekabu fucoidan powder. In these reason, to improve strong hygroscopic nature of the fermented sea tangle powder, fermented sea tangle and mekabu fucoidan powders were dissolved as ratios of 7:3, 5:5, and 3:7 (w/w) in a distilled water and then freeze dried. Xeq values of mixture powders were around average value of sum of both powders at all aw ranges. All moisture sorption isotherms of powders exhibited typical J-shaped type III. Xeq of mixture powders increased with increasing aw and decreased as increasing proportion of mekabu fucoidan powder. The Peleg model was found to accurately describe moisture sorption isotherms of powders. The results can be used to understand hygroscopic nature of powders, improve shelf life, and retain quality across postharvest processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.89-93
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• 1991

For the investigation of major taste components in loquat(Eiobotrya japonica) flesh its conte-nts and compositions of free sugars organic aicds and free amino acids were analyzed Major free sugars of the fully ripened loquat were fructose glucose and sucrose and their contents were 3,71, 3.42 and 0.46%(w/w) respectively. The content of total sugar 13.7% was 2 times higher than that of the unripe fruit. The content of total organic acid was about 0.2% (w/w) and major organic acids were malic acid -89mg% formic acid -32mg% and oxalic acid -26%mg% Thirteen kinds of free amino acids from the fully ripened loquat were confirmed. Major free amino acids were aspartic acid valine glutamic acid serine alanine and histidine and their contents were in the range of 18-30mg%.

• YAKHAK HOEJI
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• v.41 no.5
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• pp.554-558
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• 1997

Two alkaloidal components were isolated from the ether soluble part of the MeOH extract of the root bark of Euonymus japonica. Their structures were elucidated by the spe ctroscopic analylses as the sesquiterpene pyridine alkaloids derived from polyester sesquiterpenes which are characteristically detected in Celastraceae plants. These include macrocycle formed by two ester linkages between dihydro-${\beta}$-agarofuran nucleus and pyridinic dibasic acid(compound 1:evoninic acid, compound 2:wilfordic acid). The structure of compound $1[C_{47}H_{50}N_2O_{17},\;mp\;161{\sim}163^{circ}C$. $[{\alpha}]_D^{28}=+31.6^{\circ}$(c, 0.1 in EtOH)] was determined as novel structure named as euojaponine N, and compound $2[C_{48}H_{57}NO_{18},\;mp\;142{\sim}145^{circ}C,\;[{\alpha}_D^{27}=+27.0^{\circ}$(c, 0.1 in EtOH)] was identified as ebenifoline W-I reported from Maytenus ebenifolia.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.799-804
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• 2008

This study was performed to determine physicochemical and sensory quality of low-fat pork loaf containing silkworm powder and vegetable worm (Paecilomyces japonica). Total 2% of fat replacer (soy protein isolate:maltodextrin:$\kappa$-carrageenan:water=1:0.5:0.5:10, w/v) was added. The loaf was separated into CTL (control), T1 (0.2% silkworm powder), T2 (0.2% vegetable worm), T3 (0.4% silkworm powder), T4 (0.4% vegetable worm), T5 (0.1% silkworm powder+0.1% vegetable worm), and T6 (0.2% silkworm powder+0.2% vegetable worm). Pork loaf of T3 showed the highest pH value and cooking loss of pork loaves containing silkworm and vegetable worm was higher than control at day 5. 2-Thiobarbituric acid reactive substances of T2 and T5 showed significantly lower values than control and those additives may reduce lipid oxidation of meat. Overall acceptability was not adversely influenced by silkworm powder and vegetable worm at day 0 and 5. These results indicated that those silkworm powder and vegetable worm could be utilized for pork product industry.

• Food Science and Preservation
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• v.21 no.5
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• pp.636-645
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• 2014

Quality changes in frankfurter sausages with yam (Dioscorea japonica) powder added were investigated during their storage at $10^{\circ}C$ for six weeks. The sausage samples were prepared using four concentrations of yam powder: 0% (C), 0.5% (T1), 1.0% (T2), and 2.0% (w/w) (T3). After the addition of yam powder, the crude protein contents decreased, but the crude fat and carbohydrate contents increased. The thiobarbituric acid values during the storage of the frankfurter sausages were lower in the samples with higher yam concentrations. Over the storage period, the volatile basic nitrogen values increased with the increase in the amount of added yam. With the increase in the yam concentration, the $L^*$ and $a^*$ values tended to decrease, whereas the $b^*$ value increased. The instrumental texture analysis showed that the hardness value decreased with the increase in the yam concentration. The first indication of sensorial quality deterioration was noticed at week 4 for T3 and at week 5 for C, T1, and T2. In conclusion, the quality and shelf-life of the frankfurter sausages were not noticeably influenced by the addition of yam powder with a concentration of up to 1.0% (w/w), but the functional and health-promoting effects of yam were positively incorporated.