• Journal of Forest and Environmental Science
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• v.31 no.2
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• pp.119-125
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• 2015

This study examined the effects of rice straw steaming time and mixing ratio between rice straw and wood particle on the properties of mixed particle board from Acacia mangium Willd wood and rice straw. Rice straw and Acacia mangium Willd wood were collected in Hanoi, Vietnam. The particle board was three-layer particle board with the structural ratio of 1:3:1. The thickness, density and board size of the particle board were 18 mm, $0.7g/cm^3$, and $800{\times}800{\times}18$ (mm, including trimming), respectively. A resin mixture between commercial Urea-formaldehyde (U-F) adhesive and methylene diphenyl isocyanate (MDI) adhesive was used with a dosage of 12% for the core layer and 14% for the surface layer. In this experimental design, the steaming time for rice straw was 15, 30, 45, 60, and 75 minutes at $100^{\circ}C$. The rice straw-wood mixing ratio was 10, 20, 30, 40, and 50%. The results showed that both mixing ratio and steaming time affect the properties of the particleboard, but the mixing ratio has a stronger impact. A higher mixing ratio and a longer steaming time resulted in a better quality of particleboard. The optimal steaming time for rice straw was 46.12 minutes with the straw-wood mixing ratio of 29.85% with the following characteristics of the particle board: the modulus of rupture (MOR) of 14.64 MPa, internal bond strength (IB) of 0.382 MPa, thickness swelling (TS) of 8.83%, and board density of $0.7-0.7g/cm^3$.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1212-1217
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• 2009

This study examined the influence of manufacturing processes and extraction conditions on the chemical compositions of green tea. Green tea samples grown in various areas (Korea, China, and Japan) and processed by 4 different methods (steaming, pan-firing, steaming and pan-firing, and heavy roasting after steaming and pan-firing) were collected for study. The chemical compositions of the green tea extracts and infusions were different according to their processing methods and extraction conditions, including catechins, caffeine, and free amino acids contents. In all samples analyzed, (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), and theanine were determined as the major catechins and free amino acid, respectively. Studies of samples grown in the same area (Jeju; Korea) showed that there were significant differences in the concentrations of catechins and caffeine in extract and infusion according to the processing methods. These results indicate that processing methods influenced the chemical compositions of the green tea extracts and infusions.

• Korean Journal of Medicinal Crop Science
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• v.22 no.3
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• pp.223-230
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• 2014

This study was performed to enhance contents of low molecular ginsenoside using steaming and fermentation process in low quality fresh ginseng. For increase in contents of Rg2, Rg3, Rh2 and CK in low quality fresh ginseng, a steaming process was applied at $90^{\circ}C$ for 12 hr which was followed by fermentation process at Lactobacillus rhamnosus HK-9 incubated at $36^{\circ}C$ for 72 h. The contents of ginsenoside Rg1, Rb1, Rc, Re and Rd were decreased with the steaming associated with fermentation process but ginsenoside Rg2, Rg3, Rh2 and CK increased after process. It was found that under the steaming associated with fermentation process, low molecule ginsenosides such as Rg2, Rg3, Rh2 and CK were increased as 3.231 mg/g, 2.585 mg/g and 1.955 m/g and 2.478 mg/g, respectively. In addition, concentration of benzo[${\alpha}$]pyrene in extracts of the low quality fresh ginseng treated by the complex process was 0.11 ppm but it was 0.22 ppm when it was treated with the steaming process. This result could be caused by that the most efficiently breakdown of 1,2-glucoside and 1,4-glucoside linkage to backbone of ginsenosides by steaming associated with fermentation process. This results indicate that steaming process and fermenration process can increase in contents of Rg2, Rg3, Rh2 and CK in low quality fresh ginseng.

• Journal of the Korean Society of Food Culture
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• v.17 no.5
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• pp.653-662
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• 2002

Korean native Perilla Jangachi (salted and fermented vegetable) is popular and well-known but little study on its composition and most palatable condition has been reported. This study was performed to observe the change in the contents of chemical components and sensory evaluation of Perilla Jangachi which was prepared through two processing. First, as a pretreatment, Perilla leaves were soaked in salt water. The optimal level of salt concentration and soaking time (salt 4%, soaking time 42hours) was determined. Second, soaked Perilla Jangachi was steamed and then fermented in various ingredients like soy sauce, sugar, onion and so on. In this study, Perilla Jangachi was made by 3 levels of steaming time(30 seconds, 60 seconds, 90 seconds) and onion contents (10%, 30%, 50%). The optimal level of onion contents and steaming time was determined with the results of sensory evaluation by response surface methodology and analysis of composition. Sodium contents were decreased as the levels of onion contents were increased. Flavonoids contents weren't increased although contents of onion were increased. But they were influenced on steaming time that as the levels of steaming time were shortened, flavonoids contents were increased. To lengthen the shelf-life of Perilla Jangachi, the activities of enzyme peroxidase - which changes Jangachi's quality bad - by various levels of steaming time were measured. After steaming 50 seconds, peroxidase became inactive. Reducing sugar contents were decreased relying on either increased steaming time and onion contents. While steaming 30 seconds and 10% onion contents, the content of reducing sugar was 0.858% but steaming 90 seconds and 50% onion contents, it became 0.372%. Among the sensory attributes, brownness was increased as onion contents increased and steaming more than 60 seconds. Saltiness, sweetness, perilla flavor were greater relying on decreased onion contents. Toughness was decreased as both the amounts of onion and steaming time were increased. With this results, the most optimal adding level of onion content and steaming time was determined. Steaming 72 seconds and adding onion 27% was established as a optimal condition of Perilla Jangachi.

• The Korea Journal of Herbology
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• v.31 no.3
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• pp.59-69
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• 2016

Objectives： Presently Mume Fructus (MF) undergoes fumigation, which produces benzo[a]pyrene. As a primary analysis with the aims to minimize the production of benzo[a]pyrene and to suggest standards for processing the MF, the steaming method was chosen among the various processing methods, and reviewed through a series of experiments.Methods： Methods：Pitted and un-pitted MF were steamed and processed into samples. After testing level of benzo[a]pyrene, the samples were analyzed for amount of polyphenol and flavonoids. Scavenging activities of the samples for the DPPH and ABTS radicals were tested. In order to measure anti-inflammatory effects of the samples, cell survival rate was investigated using CCK-8 Assay. Also, water extracts of dried and steamed MF were administered to the RAW 264.7 cells to compare expressions of NO, PGE₂, IL-1β, and TNF-α. In addition, anti-diarrhea effects of the herbal medicine were tested on animal models with diarrhea induced by MgSO₄ and Castor oil.Results： Regardless of pitting, processed MF contained no benzo[a]pyrene. Anti-oxidation effect increased in relation to the frequency of steaming process. However, extracts of dried and steamed MF suppressed different kinds of inflammation factors, and extract of dried MF showed superior anti-diarrhea effect than extract of steamed MF.Conclusions： It is suggested that steaming method of MF is recommended for processing the herbal medicine without the production of benzo[a]pyrene. But regarding that dried and steamed MF showed differences in their anti-oxidative, anti-inflammatory, and anti-diarrhea effects, it is recommended to perform further researches on different efficacies of MF according to their processing methods.

• Journal of the Korean Wood Science and Technology
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• v.30 no.3
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• pp.85-90
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• 2002

This study was carried out to investigate the dimensional stability of bentwoods by three treatments: steaming, urethane varnish coating, and polyethylene glycol (PEG) treatment. Bentwood processing employed a bending-jig with only 4 cm radius of curvature (ROC). The used species were bitter wood (Picrasma quassioides), painted maple (Acer mono), and birch (Betula schmidtiii). The bending properties of these are well-known in bentwood production (Jung et al., 2002). The bentwoods were treated repeated at room temperature [20℃, RH 80% (12 hours) and 40℃ under RH 10% (12 hours)]. To estimate the dimensional stability of bentwoods, we measured the radius of curvature and end-distance. The best results could be attained with PEG treatment. Steaming was the worst treatment. Comparing the properties of the different species, the dimensional stability of bitter wood was excellent. It was concluded that the steaming treatment was unsuitable for dimensional stability of bentwoods.

• The Korea Journal of Herbology
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• v.33 no.1
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• pp.27-35
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• 2018

Objectives : Gastrodiae Rhizoma extract (GE) is possess the various bioactive compounds such as gastrodin, vanilyl alcool and p-hydroxybenzyl alcohol. Various processing methods such as steaming have been widely applied to ease ingestion and enhance the therapeutic effects of plant materials including GE in East-Asia area. The aim of this study was to evaluate the dermal bioactive properties of GE. Methods : First, total phenol, total flavonoid, gastrodin and ergothionein contents of GE were measured. In order to evaluate the dermal bioactive properties of steamed GE compared with not-steamed GE, tyrosinase, collagenase and elastase inhibitory activity were tested. Furthermore, the anti-oxidant activity of GE assessed based on DPPH and ABTS radical scavenging assay. Results : In results, total phenol and total flavonoid contents were increased when 9 times steamed compared to not-steamed GE. Also, GE increased gastrodin contents, in proportion to the number of steaming times and ergothioneine content was abolished in the steaming state. The DPPH radical scavenging activity of GE increased by steaming, but the ABTS radical scavenging activity was not related to the steaming process. In addition, the tyrosinase inhibitory activity was increased as the number of steaming times of GE increased. Collagenase was most inhibited by 4 times steamed GE, and elastase was inhibited by 8 times steamed GE. Conclusion : In conclusion, these results suggest that steamed GE extract has the potential as a cosmetic material which possess anti-oxidant and whitening activities than not steamed GE.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.1-5
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• 2005

Eight flavonoids, apigenin-6-C-β-D-glucopyranosy l-8-C-β-D-glucopyranoside (AGG), quercetin 7-O-β-D­glucopyranoside (QG), luteolin 7-O-β-D-glucopyranoside (LG), quercetin 7-O-(6'-O-acetyl)-β-D-glucopyranoside (QAG), luteolin 7-O-(6'-O-acetyl)-β-D-glucopyranoside(LAG), quercetin (Q), luteolin (L) and acacetin 7-O-β­D-glucuronide (AG) were determined by HPLC in the safflower (Carthamus tinctorius L.) leaf during growth and processing. During growth, levels of five flavonoid glycosides (AGG, QG, LG, QAG, & LAG) in the leaf increased progressively at over time according to growth stages, reached a maximum before June 11, and then decreased sharply, while those of three flavonoid aglycones (Q, L, & AG) increased greatly at the early stage of growth, reached a peak before May 28, and then decreased rapidly. During the steaming process, contents of five flavonoid glycosides increased rapidly with increased steaming time, reached a maximum after 5 min of steaming, and then decreased, whereas those of flavonoid aglycones except for AG decreased sharply with increased steaming time. During the roasting process, contents of three flavonoid glycosides decreased rapidly with increased roasting time, whereas those of two acetylflavonoid glycosides (QAG & LAG) and three flavonoid aglycones increased progressively with increased roasting time, reached a maximum after 3 min of roasting, and then decreased. These results suggest that appropriate steamed and roasted safflower leaves are a rich source of flavonoids, and may be a good source of bioactive components as a functional leaf tea.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.271-271
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• 2017

Tartary buckwheat is known for its high rutin (quercetin 3-rutinoside) content which has antioxidant, anti-inflammatory, and anticarcinogenic effects. The buckwheat tea which is popular in Korea, is dependent on the quality of applied processing methods (steaming, dehuling, and roasting). This study focused on the evaluation of changes in rutin and anti-oxidant contents during the processing of tartary buckwheat tea. Raw tartary buckwheat seeds contains the highest quantities of rutin (2,212 mg/100 g D.W.). Soaking in water and steaming the whole seeds of tartary buckwheat significantly decreased its rutin and quercetin contents. Whereas the contents of rutin and quercetin in dehulled groats increased after steaming. The process of roasting with $70-80^{\circ}C$ for 2-3 min significantly decreased the contents of rutin (992 mg/100 g D.W.) and quercetin (12.8 mg/100 g D.W.). In the processing of tartary buckwheat tea, rutin content dropped about 45% in comparison with raw whole seeds.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.361-369
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• 2017

Background: The chemical constituents of Panax ginseng are changed by processing methods such as steaming or sun drying. In the present study, the chemical change of Panax ginseng induced by steaming was monitored in situ. Methods: Samples were separated from the same ginseng root by incision during the steaming process, for in situ monitoring. Sampling was sequentially performed in three stages; FG (fresh ginseng) ${\rightarrow}$ SG (steamed ginseng) ${\rightarrow}$ RG (red ginseng) and 60 samples were prepared and freeze dried. The samples were then analyzed to determine 43 constituents among three stages of P. ginseng. Results: The results showed that six malonyl-ginsenoside (Rg1, Rb1, Rb3, Rc, Rd, Rb2) and 15 amino acids were decreased in concentration during the steaming process. In contrast, ginsenoside-Rh1, 20(S)-Rg2, 20(S, R)-Rg3 and Maillard reaction product such as AF (arginine-fructose), AFG (arginine-fructose-glucose), and maltol were newly generated or their concentrations were increased. Conclusion: This study elucidates the dynamic changes in the chemical components of P. ginseng when the steaming process was induced. These results are thought to be helpful for quality control and standardization of herbal drugs using P. ginseng and they also provide a scientific basis for pharmacological research of processed ginseng (Red ginseng).