• Title/Summary/Keyword: acidic pH

Search Result 1,509, Processing Time 0.039 seconds

Property and Inhibition of the Hydrolysis of Ginseng Saponins by Organic Acids Neutralization in Ginseng Extract Preparations (인삼(人蔘)의 가열추출(加熱抽出) 과정(過程) 중 사포닌의 가수분해(加水分解) 특성(特性) 및 유기산중화(有機酸中和)에 의한 분해억제(分解抑制))

  • Jeong, Seung-Ii;Lee, Yong-Gu;Kim, Cheon-Suk;Lee, Seong
    • Korean Journal of Medicinal Crop Science
    • /
    • v.6 no.4
    • /
    • pp.305-310
    • /
    • 1998
  • Glucosidic bond at the $C_{20}$ position of the sapogenins was hydrolyzed easily in the lower pH, higher temperature and longer time to give prosapogenins and sugars. The glucosidic bond of saponin at the $C_3\;of\; ginsenoside-Rb_1\;$, which is secondary carbon, was relatively stable due to the low electron density of -0.2. But the bond of saponin at the $C_{20}$ position, which is tertiary carbon with the relatively high electron density of -0.3, was liable to be hydrolyzed even in weak acidic solution by the increase of heating time. On the other hand, fresh and white ginseng contained 4.12 mg/g, 13.05 mg/g of citric acid, 0.68 mg/g, 2.18 mg/g of malonic acid, 1.13 mg/g, 3.68 mg/g of oxalic acid, 2.68 mg/g, 8.62 mg/g of malic acid and 0.13 mg/g, 0.46 mg/g of succinic acid, respectively. Ginseng saponins were very stable in ginseng extract neutralized with sodium carbonate or sodium bicarbonate corresponding to the equivalent amount of the total organic acid in the ginseng.

  • PDF

Chemical burns of the oral mucosa caused by Policresulen: report of a case (Policresulen 오용에 의한 구강 궤양의 발병 증례 및 화학화상에 대한 고찰)

  • Jung, Jung-Woo;Byun, Jin-Seok;Jung, Jae-Kwang;Choi, Jae-Kap
    • Journal of Oral Medicine and Pain
    • /
    • v.38 no.2
    • /
    • pp.109-114
    • /
    • 2013
  • Chemical burn on the oral mucosa is caused by contact with various chemical products and manifests with localized mucositis, keratotic white lesions, bleeding, and painful tissue surface due to the coagulation of the tissue. Policresulen ($Albothyl^{(R)}$) is a topical antiseptic, commonly used over-the-counter drug for vaginitis, thrush and stomatitis. This drug is highly acidic with pH 0.6, and can act as a strong corrosive agent to oral mucosa. When inadvertently used in oral cavity, it may cause chemical burns of oral mucosa, resulting necrosis and bleeding surface resembling to erythema multifome. A 56 years old female patient presented with the chief complaints of painful ulcerations on the tongue, the upper and lower lips. On intraoral examination, an erythromatous, erosive or ulcerative surface covered with inflammatory exudates or bleeding crust is observed on the anterior half of the tongue and the upper and lower lips. She has occasionally applied the policresulen solution topically on the tongue to relieve pain from recurrent focal glossitis for about 10 years. In this time she applied it broadly and repeatedly to the tongue, the upper and lower lips for the purpose of pain relief by herself without instruction by physician or dentist. After cessation of policresulen application, the oral mucosa was rapidly recovered with use of topical steroids. In 2 weeks the lesions subsided completely. In summary, inadvertent use of $Albothyl^{(R)}$ on oral mucosa may result in chemical burn, causing mucosal erosion, ulceration and inflammation. It can be recovered by topical use of corticosteroid for 2 weeks after cessation of using $Albothyl^{(R)}$.

Cadmium and Zinc Uptake Characteristics of Corn Plant in Arable Soil Contaminated by Smelting Factory Source

  • Hong, Chang-Oh;Gutierrez, Jessie;Oh, Ju-Hwan;Lee, Yong-Bok;Yu, Chan;Kim, Pil-Joo
    • Korean Journal of Environmental Agriculture
    • /
    • v.26 no.3
    • /
    • pp.210-216
    • /
    • 2007
  • The cadmium (Cd) and zinc (Zn) contamination of soils and cultivated crop plants by zinc smelting activities was studied. In the study area of the vicinity of ${\triangle}{\triangle}$ zinc smelting factory in Korea, soils and corn plants were sampled at corn harvesting stage and analyzed Cd and Zn concentration as well as Cd and Zn fraction and chemical properties in soils. At 600 m radius of studied area, Cd and Zn were highly accumulated in the surface soils (0 - 20 cm) showed greater than the Korean warning criteria (Cd 1.5, Zn 300 mg $kg^{-1}$) with corresponding values 1.7 and 407 mg $kg^{-1}$, respectively. The leaf part gave higher Cd concentration with the corresponding value of 9.5 mg $kg^{-1}$ as compared to the stem and grains pare (1.6 and 0.18 mg $kg^{-1}$), respectively. Higher Zn concentration was also obtained from the leaf part of the corn plant which gave the value of 1,733 mg $kg^{-1}$. The stem and grain part gave corresponding values of 547 and 61 mg $kg^{-1}$. The order of the mean Cd concentration in fractions is F3 (oxidizable fraction) > F2 (reducible fraction) > F4 (residual fraction) > F1 (exchangeable + acidic fraction). A highly positive correlation is observed between F2 and concentration of Cd and Zn in both plant pare, leaf and grain. Highly positive correlations are shown in the pH exchangeable Ca and Mg, and CEC when correlated with Cd and Zn bound to F4 fractions. To reduce Cd and Zn uptake by corn plant in an arable land heavily contaminated with Cd and Zn as affected by smelting factory, an efficient and effective soil management to increase soil pH and CEC is thus recommended.

Changes in Microflora and Enzymes Activities of Traditional Kochujang Prepared with Various Raw Materials (담금원료에 따른 전통식 고추장의 숙성 중 미생물과 효소력의 변화)

  • Shin, Dong-Hwa;Kim, Dong-Han;Choi, Ung;Lim, Mi-Sun;An, Eun-Young
    • Korean Journal of Food Science and Technology
    • /
    • v.29 no.5
    • /
    • pp.901-906
    • /
    • 1997
  • In order to reproduce and improve quality of traditional kochujang, various raw materials were added to prepare kochujang by replacing part of the glutinous rice. Chemical composition, microbial characteristics and enzyme activities were investigated during fermentation. Crude protein and salt contents of kochujang did not change significantly during fermentation, but moisture contents increased linearly. The pH and titratable acidity of kochujang changed little in garlic added group. The viable cell counts of aerobic bacteria and yeasts in the kochujang increased until 60 days of fermentation and then decreased slowly except for the garlic added group in which they increased during the last period of fermentation. Aerobic bacterial count did not show any remarkable differences among the samples and slowly decreased after 60 days of fermentation. The activities of liquefying and saccharifying amylases decreased until 45 days, but increased at 60th day. Acidic protease activities of each group were strong during the initial period, but neutral protease showed the highest activity from the 30 to 45 days of fermentation. Protease activities increased by addition of soy sauce, Chinese matrimony vine and purple sweet potato.

  • PDF

Antimicrobial Effect of Lithospermi radix (Lithospermum erythrorhizon) Extract (자초(Lithospermum erythrorhizon) 추출물의 항균특성)

  • Park, Uk-Yeon;Chang, Dong-Suck;Cho, Hak-Rae
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.21 no.1
    • /
    • pp.97-100
    • /
    • 1992
  • The optimum condition for the extraction of antimicrobial substance from Lithospermi radix was investigated. For the purpose of obtaining basic data for the development of natural preservatives and for the prevention of food poisoning accidents, its antimicrobial activity was tested against several kinds of saprophytic microbes and food poisoning bacteria. The optimum condition for extraction of antimicrobial substance was to steep Lithospermi radix into 95% ethanol for 24 hours at room temperature. Antimicrobial activity was observed at the pH range $5.0{\sim}8.0$, but its activity became stronger at acidic condition. The result of ion exchange chromatography was showed that the antimicrobial activity of anionic portion was more apparent than that of cationic portion. The antimicrobial activity against Gram positive bacteria was stronger than that of Gram negative bacteria and the growth of food poisoning bacteria such as S. aureus and V. parahaemolyticus was inhibited in the concentration of 0.1% for 48 hours. As for mold and yeast, the growth of some kinds of these organisms was inhibited in the concentration of 0.1 % for 48 hours and the growth of nearly all the fungi was inhibited in the concentration of 0.15% for 96 hours.

  • PDF

Identification of the Volatile Components in Korean Ordinary Kochujang (한국재래식(韓國在來式) 고추장의 향기성분동정(香氣成分同定))

  • Ahn, Cheol-Woo;Kim, Jong-Kyu;Sung, Nack-Kie
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.16 no.3
    • /
    • pp.27-34
    • /
    • 1987
  • The present paper was attempted to obtain the basic date concerning a reasonable preparing method and optimum fermentation conditions of Kochujang (Red pepper paste). To establish the standard quality of Kochujang, the chemical compositions and the volatile components of Kochujang was discussed. The native Kochujang collected from 80 households contained 40.51% of moisture, 6.00% of salts, 3.25 % of crude fat, 10.30 % of crude ash, pH 4.79, 9.28ml of tillable acidity. 19.60% of reducing sugar, 179.51 mg/100g of amino nitrogen and 4.43% of total nitrogen. The volatiles of Kochujang were extracted by a steam-distillation under the reduced pressure and determined by gas chromatography-mass spectrometry (GC-MS). Total volatile components identified in the native Kochujang were 46 components, i. e., 30 components in neutral fraction, 8 components in phenolic fraction and 8 components in acidic fraction, respectively. But no components were detected basic fraction.

  • PDF

Application of Rice Polishing By-products to Processed Rice Food (I) - Antioxidative Effect of Black Rice Bran Pigment Fraction on Rice Embryo Lipid Oxidation - (쌀 가공식품 제조용 소재로서의 도정 부산물 활용 방안 (I) - 흑미 미강 색소 분획의 쌀 배아 산패 억제 효과 -)

  • Cho, Min-Kyung;Kim, Sung-Hong;Kang, Mi-Young
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.18 no.3
    • /
    • pp.361-367
    • /
    • 2008
  • This study examined the physicochemical properties of rice embryo in order to investigate the antioxidative effect of black rice bran pigment fraction on rice embryo lipid oxidation. Color stability of rice bran pigment fraction and acid value of added rice embryo were determined at various conditions of pH, temperature, and storage time. Rice embryo contained more crude protein (22.1%) compared to the rice bran (9.4%). However, rice embryo had a higher lipid content than rice bran, causing lipid oxidation during storage. Pigment fraction were relatively stable in acidic pH of 3.0 stored at $4^{\circ}C$ for 9 days. Rice embryo showed increased acid value with increased storage time and temperature. Furthermore, rice embryo with pigment fraction resulted in lower acid value compared to the control group. Therefore, addition of black rice bran pigment fractions to rice embryo improved storage capacity.

  • PDF

Physicochemical Characteristics of Yellowtail Myosin and Whelk Paramyosin (방어 Myosin과 갈색띠 매물고둥 Paramyosin의 물리화학적 성질)

  • Pyeun, Jae-Hyeung;Choi, Yeung-Joon
    • Korean Journal of Food Science and Technology
    • /
    • v.19 no.1
    • /
    • pp.29-37
    • /
    • 1987
  • The native myosin and paramyosin extracted from the ordinary muscle of yellowtail (Seriola quinqueradita) and the adductor muscle of whelk (Neptunea arthritica cumingi) were studied for their physico-chemical characteristics. Molecular weight, molar extinction coefficient at 278 nm and intrinsic viscosity were accounted for $4.6{\times}10^5$dalton, 5.44 in $E^{1cm}_{1%}$ and 1.60 dl/g in yellowtail myosin, and $2.0{\times}10^5$ dalton, 3.04 in $E^{1cm}_{1%}$ and 2.60 dl/g in whelk paramyosin, respectively. Yellowtail myosin showed a $0.342\;{\mu}mole-Pi/min/mg-protein$ of ${Ca}^{2+}-ATPase$ activity and contained 40 group-SH/mole-myosin. The ratio of polar amino acids to non-polar amino acids and that of acidic amino acids to basic amino acids were 0.54 and 1.64 in yellowtail moysin, and were 0.47 and 2.42 in whelk paramyosin, respectively.

  • PDF

Chemical Properties of Precipitation in Related to Wind Direction in Busan, Korea, 2009 (풍향에 따른 2009년 부산지역 강수의 화학적 특성)

  • Jung, Woon-Seon;Park, Sung-Hwa;Lee, Dong-In;Kang, Deok-Du;Kim, Dongchul
    • Journal of the Korean earth science society
    • /
    • v.35 no.2
    • /
    • pp.104-114
    • /
    • 2014
  • The variation of acidity, conductivity, and ion components in precipitation depending on the dominant wind direction was investigated from January, 2009 to December 2009 in Busan, Korea. Both southwesterly and northeasterly winds were dominant in Busan area. The volume-weighted mean acidity showed pH 7, and the high conductivity indicated 200 ${\mu}scm^{-1}$ in westerly wind. The volume-weighted mean equivalent concentration showed higher value of $K^+$ and $Cl^-$ in all wind directions. The composition ratio of $NO{_3}^-/SO{_4}^{2-}$ showed over 3 in northerly wind. The neutralization factors have been found to have higher value for potassium ion in northeasterly, easterly, southwesterly, and westerly winds compared with different wind directions, which indicated significant neutralization of acidic components over the region by potassium. Also, the concentration of sea salt has been found over 800 ${\mu}sm^{-3}$ in northeasterly and southwesterly winds. Air masses passing through Manchuria, Inner Mongolia plateau, China, and Russia in spring, autumn, and winter covered Busan, Korea in northerly, westerly, and northwesterly winds. However, air masses passing through the ocean in summer covered Busan, Korea in easterly, northeasterly, and southwesterly winds. Therefore, the variation of acidity, conductivity, and ionic components contained in precipitation shows each seasonal characteristics with prevailing wind systems between the continental and coastal area in Busan, Korea.

The State of Mulberry Cultivation and It's Development in High Land of Benguet Province, Philippines (필리핀 벤규트의 고지대 뽕밭현황 및 개선방안)

  • Ryu, Keun Sup
    • Current Research on Agriculture and Life Sciences
    • /
    • v.14
    • /
    • pp.85-100
    • /
    • 1996
  • The Studies were conducted to provide the state of mulberry cultivation and it's development in Banguet province (high land) of Philippines. Philippines initiated the sericulture industry with the technical asistance of Japan in 1974 and established mulberry field and sericultural facilities with technical asistance of Korea in 1990 and 1995. The required average of 100 to 150mm per month is not available during the dry season from December to March. Therefore mulching with grass which is available abundantly in the Philippines should be established to conserve moisture, to control soil erosion, surface ran-off and also to increase the humus content in the soil. In chemical properties of mulberry field, the pH value of soil is 4.7, organic matter 1.6%, and available phosphorus 6ppm. Therefore, all fields should do liming and be applied compost. To improve leaf yield for mulberry planted under partial shade area of pine trees, more pruning of pine tree should be done for good sunshining of mulberry, more liming and compost should be applied to improve acidic soil. To control the leaf roller, DDVP and KAFIL are able to be used. When spraying insecticides to control mulberry insect pests, care should be taken to consider the residual effects of chemicals on the leaf. Leaf should be fed to silkworms only after the leaves are free of any residual effects.

  • PDF