• Title/Summary/Keyword: Oxalic acid pretreatment

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Quality characteristics of Yakju containing pretreated lotus leaves (전처리를 달리한 연잎을 이용한 약주의 품질특성)

  • Choi, Jeong-Sil;Yeo, Soo-Hwan;Choi, Han-Seok;Jeong, Seok-Tae
    • Food Science and Preservation
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    • v.23 no.2
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    • pp.204-210
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    • 2016
  • This study aimed to find an effective preservation method of lotus leaves for the preparation of lotus-leaf Yakju throughout the year. The characteristics of Yakju containing lotus leaves pretreated by blanching, steaming, roasting, and drying were investigated in this study. The chemical properties of Yakju (pH, amino acidity, alcohol content, and volatile acid content) were significantly different for all treatments, except for the total acid content. The polyphenol content ranging from 315.89 to 462.63 ppm (p<0.05) was significantly different depending on pretreatment method L color value for Yakju was not significantly different all treatments, while a value was significantly different in Yakju containing frozen stored leaves after pretreatment. The b value was lowest for the blanching treatment, and was significantly different for all treatments. Among the organic acids present in Yakju, the oxalic, citric, and malic acid contents were significantly different for all treatments. In sensory evaluation, lotus-leaf Yakjus containing fresh leaves and dried leaves were preferred to the others in color and flavor among Yakjus prepared with lotus leaves before cold storage. However, among the Yakjus prepared with lotus leaves after cold storage, that containing blanched leaves was preferred to the others in terms of flavor, taste, and overall acceptability.

Pretreatment for Cu electroplating and Etching Property of Cu-Cr Film (Cu-Cr합금 박막의 구리 전기도금을 위한 전처리 및 에칭 특성에 관한 연구)

  • Kim, N. S.;Kang, T.;Yun, I. P.;Park, Y. S.
    • Journal of the Korean institute of surface engineering
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    • v.26 no.3
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    • pp.149-157
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    • 1993
  • In the study of TAB(Tape Automated Bonding)technologies, Cu-Cr sputtered seed layer has been used to improve the adhesion between Polyimide and Cu film and electrical properties. But the Cu electrodeposit on Cu-Cr film had poor adhesion or powder-like form due to the surface Cr oxides on the Cu-Cr film. By means of activating the Cu-Cr film with the oxalic acid and phosphoric acid, the Cu film with the improved adhesion could be coated on the Cu-Cr sputtered film in CuSO4 solution. The etching rate was compared with increasing the Cr content of the sputtered Cu-Cr film, and anodic polarization curve in FeCl3 solution was investigated. With increasing the Cr content, the etching rate was reduced. The clean etching cross section could be obtained with increasing the concentration of FeCl3 solution. But above the 13 w/o Cr content, Cu-Cr sputtered film could not bed etched cleanly only with FeCl3 solution and additives were needed.

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Improved Ethanol Production from Deacetylated Yellow Poplar (Liriodendron tulipifera) by Detoxification of Hydrolysate and Semi-SSF (에탄올 향상을 위한 탈아세틸화 백합나무 당화액의 발효저해물질 제거와 semi-동시당화발효)

  • Kim, Jo-Eun;Lee, Jae-Won
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.494-500
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    • 2016
  • In order to remove acetyl group from yellow poplar, deacetylation was performed using sodium hydroxide (NaOH) prior to oxalic acid pretreatment. During the deacetylation ($60^{\circ}C$ for 80 min, 0.8% NaOH), most of the acetyl group were removed from hemicellulose. Simultaneous saccharification and fermentation (SSF) and semi-SSF were carried out based on solid loading (10, 12.5, 15%) of deacetylated biomass and pre-hydrolysis with enzymes (0, 6, 12, 24 h). The highest ethanol was obtained as 26.73 g/L after 120 h when 10% of biomass was used for SSF. It is corresponding to 88.41% of theoretical ethanol yield. At the 12.5% and 15% of biomass loading, the highest ethanol was obtained from 6 h pre-hydrolysis. It was 32.34 g/L and 27.15 g/L, respectively, and corresponding to ethanol yield of 85.58 and 59.87%. In order to remove fermentation inhibitors from hydrolysates, overliming was performed using calcium hydroxide ($Ca(OH)_2$). The highest ethanol was 5.28 g/L after 72 h of fermentation.

Catalytic Oxidation of Aromatic Compounds over Spent Ni-Mo and Spent Co-Mo based Catalysts: Effect of Physico-chemical Pretreatments (폐 Ni-Mo 및 폐 Co-Mo계 촉매상에서 방향족 화합물의 촉매산화: 물리화학적 전처리 효과)

  • Shim, Wang Geun;Kang, Ung Il;Kim, Chai
    • Applied Chemistry for Engineering
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    • v.21 no.1
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    • pp.63-70
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    • 2010
  • Transition metal based spent catalysts (Ni-Mo and Co-Mo), which were scrapped from the petrochemical industry, were reused for the removal processes of volatile organic compounds (VOCs). Especially the optimum regeneration procedures were determined using the removal efficiency of VOCs. In this work, the spent Ni-Mo and spent Co-Mo catalysts were pretreated with different physic-chemical treatment procedure: 1) acid aqueous solution, 2) alkali solution, 3) chemical agent and 4) steam. The various characterization methods of spent and its regenerated catalysts were performed using nitrogen adsorption, X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with an energy dispersive spectrometry (EDS). It was found that all spent catalysts were found to be potentially applicable catalysts for catalytic oxidation of benzene. The experimental results also indicated that among the employed physico-chemical pretreatment methods, the oxalic acid aqueous (0.1 N, $C_2H_2O_4$) pretreatment appeared to be the most efficient in increasing the catalytic activity, although the catalytic activity of spent Ni-Mo and spent Co-Mo catalysts in the oxidation of benzene were greatly dependent on the pretreatment conditions. The pretreated spent catalysts at optimum condition could be also applied for removing other aromatic compounds (Toluene/Xylene).

Menadione Sodium Bisulfite-Protected Tomato Leaves against Grey Mould via Antifungal Activity and Enhanced Plant Immunity

  • Jo, Youn Sook;Park, Hye Bin;Kim, Ji Yun;Choi, Seong Min;Lee, Da Sol;Kim, Do Hoon;Lee, Young Hee;Park, Chang-Jin;Jeun, Yong-Chull;Hong, Jeum Kyu
    • The Plant Pathology Journal
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    • v.36 no.4
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    • pp.335-345
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    • 2020
  • Tomato grey mould has been one of the destructive fungal diseases during tomato production. Ten mM of menadione sodium bisulfite (MSB) was applied to tomato plants for eco-friendly control of the grey mould. MSB-reduced tomato grey mould in the 3rd true leaves was prolonged at least 7 days prior to the fungal inoculation of two inoculum densities (2 × 104 and 2 × 105 conidia/ml) of Botrytis cinerea. Protection efficacy was significantly higher in the leaves inoculated with the lower disease pressure of conidial suspension compared to the higher one. MSB-pretreatment was not effective to arrest oxalic acid-triggered necrosis on tomato leaves. Plant cell death and hydrogen peroxide accumulation were restricted in necrotic lesions of the B. cinereainoculated leaves by the MSB-pretreatment. Decreased conidia number and germ-tube elongation of B. cinerea were found at 10 h, and mycelial growth was also impeded at 24 h on the MSB-pretreated leaves. MSB-mediated disease suppressions were found in cotyledons and different positions (1st to 5th) of true leaves inoculated with the lower conidial suspension, but only 1st to 3rd true leaves showed decreases in lesion sizes by the higher inoculum density. Increasing MSB-pretreatment times more efficiently decreased the lesion size by the higher disease pressure. MSB led to inducible expressions of defence-related genes SlPR1a, SlPR1b, SlPIN2, SlACO1, SlChi3, and SlChi9 in tomato leaves prior to B. cinerea infection. These results suggest that MSB pretreatment can be a promising alternative to chemical fungicides for environment-friendly management of tomato grey mould.

Separation of Reducing Sugars from Rape Stalk by Acid Hydrolysis and Fabrication of Fuel Pellets from its Residues (산가수분해한 유채대로부터 유리당의 분리 및 이의 잔사로부터 펠릿의 제조)

  • Yang, In;Ahn, Byoung Jun;Kim, Myeong-Yong;Oh, Sei Chang;Ahn, Sye Hee;Choi, In-Gyu;Kim, Yong-Hyun;Han, Gyu-Seong
    • Korean Journal of Plant Resources
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    • v.27 no.1
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    • pp.60-71
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    • 2014
  • This study was conducted to identify the potential of rape stalk as a raw material for biorefinery process of rape flower. At first, rape stalk (RS) was immersed in distilled water (DW), acetic acid (AA), oxalic acid (OA), sulfuric acid (SA) and sodium hydroxide (SH) solutions, and the content of reducing sugars liberated from immersed RS was analyzed. Glucose, xylose, arabinose and sucrose were detected varying with the immersion type. In particular, 1% AA-immersion of RS for 72 hr was the most effective conditions to liberate glucose from RS. Secondly, the RS residues were used for elementary analysis and fabrication of fuel pellets. In addition to the solution type, concentration of immersion solutions (0%, 1%, 2%) and immersion time (24, 72, 120 hr) were used as experimental factors. The contents of nitrogen, sulfur and chlorine reduced effectively through the immersion of RS in DW, AA and OA solutions. For properties of RS-based pellets, bulk density and higher heating value of RS-based pellets greatly increased with the immersion of RS, and the qualities were much higher than those of the A-grade pellet of the EN standards. Ash content decreased remarkably through the immersion of RS, and was satisfied with the A-grade pellet standard. Durability was negatively affected by the immersion of RS, and did not reached to B-grade of the EN standard. In conclusion, acid immersion of RS can be a pretreatment method for the production of fuel pellet and bioethanol, but use of the immersed RS for the production of high-quality pellets might be restricted due to low durability of immersed-RS pellets. Therefore, further studies, such as investigation of detailed immersion conditions, fabrication of mixed pellets with wooden materials and addition of binders, are needed to resolve the problems.

Antioxidant Activity of The Residue Generated During Pervaporation of Bioethanol Produced from Lignocellulosic Biomass (목질계 바이오매스로부터 생산된 바이오에탄올 투과증발 과정에서 발생한 투과증발 잔류물의 항산화 활성)

  • Shin, Gyeong-Jin;Jeong, So-Yeon;Lee, Hong-Joo;Lee, Jae-Won
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.6
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    • pp.826-837
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    • 2015
  • In this study, we produced bioethanol from the original hydrolysate obtained during oxalic acid pretreatment of lignocellulosic biomass. The bioethanol was separated and concentrated by pervaporation and the residue after pervaporation was evaluated for its antioxidant activity. Xylose ($37.28g/{\ell}$) was the major product in the original hydrolysate. The original hydrolysate contained acetic acid, furfural and total phenolic compounds (TPC) as fermentation inhibitors. Acetic acid was removed by electrodialysis (ED), and $12.21g/{\ell}$ of bioethanol was produced from ED-treated hydrolysate. The TPC of ethyl acetate extracts from the residue obtained (OA-E) during pervaporation was 86.81 mg/100 g (extract). The $IC_{50}$ values of DPPH and ABTS radical scavenging activities, and reducing power of OA-E were $0.87mg/m{\ell}$, $0.85mg/m{\ell}$, and $0.59mg/m{\ell}$, respectively. Sugar degradation products and the phenolic compounds in OA-E were determined by GC-MS.

Effect of Pretreatment Conditions on Effective Components of Extracts from Safflower (Carthamus tinctorius L.) Seed (전처리조건이 홍화씨 추출물의 유효성분 함량에 미치는 영향)

  • Kim, Jun-Han;Park, Jun-Hong;Kim, Jong-Kuk;Lee, Jin-Man;Moon, Kwang-Deog
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.3
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    • pp.367-372
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    • 2002
  • In order to utilize safflower seed effectively as a food material, it was processed at the conditions including roasting temperature/time of 170$\^{C}$/10 min to 210$\^{C}$/30 min, ethanol concentration of 0 to 100% (V/V) and enzyme hydrolysis with $\alpha$-amylase, $\beta$-amylase, amyloglucosidase and cellulase. Safflower seed extracts had the highest soluble solid content at the condition of 60% ethanol concentration, roasting at 190$\^{C}$ for 20 min and hydrolysis with amyloglucosidase. Total phenolic compounds increased with the ethanol concentration, showing the highest at the condition of 80% ethanol, roasting at 170$\^{C}$ for 30 min and hydrolysis with amyloglucosidase. High level total flavonoid was observed at the condition of 80% ethanol, roasting at 210$\^{C}$ for 30 min and hydrolysis with amyloglucosidase. Safflower seed had sucrose as major free sugar as well as xylose and arabinose as minor free sugars. Organic acids in safflower seed included oxalic, citric, magic and fumaric acid. Serotonin I (N-[2-(5-hydroxy-1H-indo-1-3-yl)ethyl]ftrulamide) and serotonin II (N-[2-(5-hydroxy-1H-indol-3yl)ethyl]-p-coumaramide) as antioxidant compounds increased with ethanol concentration, showing the highest revel at 60% ethanol. Acacetin content increased with temperature and roasting time, with a maximum of 69.47 mg% at 210$\^{C}$ for 30 min.