• Title/Summary/Keyword: pH-stat control

Search Result 15, Processing Time 0.023 seconds

Effect of Cacao Extract on Hydrolysis of Oil vs. Emulsion in pH-Stat Digestion Model (pH-Stat Digestion Model에서 카카오 추출물이 Oil과 Emulsion의 가수분해에 미치는 영향)

  • Lee, Ji-Hyun;Shin, Jung-Ah;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.45 no.4
    • /
    • pp.533-541
    • /
    • 2016
  • Effect of polyphenols-rich cacao extract (CE) on lipid hydrolysis by pancreatic lipase was investigated by pH-stat digestion. Two types of substrate (oil vs. emulsion) prepared from soybean oil and CE were studied as types I and II. In the case of type I, addition of CE did not show retardation of lipid hydrolysis, showing that pancreatic lipase was not inhibited. Final digestibility rate (${\Phi}$ max, %) and initial rate (mM/s) of the 24-h aged control (52.31%, 0.03 mM/s) were similar to those of the CE-added sample (58.88%, 0.03 mM/s). However, in the case of typeII, the hydrolysis rates of the control and CE-added emulsion showed distinct differences as aging time increased to 43 days, showing lower digestion in the CE-added emulsion than the control. After 43 days, ${\Phi}$ max values of the control and CE-added emulsion were 92.13% and 77.68%, respectively.

Non-invasive Methods for Determination of Cellular Growth in Podophyllum hexandrum Suspension Cultures

  • Chattopadhyay, Saurabh;Bisaria, V.S.;Scheper, T.;Srivastava, A.K.
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.7 no.6
    • /
    • pp.331-334
    • /
    • 2002
  • Culture conductivity and on-line NADH fluorescence were used to measure cellular growth in plant cell suspension cultures of Podophyllum hexandrum. An inverse correlation between dry cell weight and medium conductivity was observed during shake flask cultivation. A linear relationship between dry cell weight and culture NADH fluorescence was obtained during the exponential phase of batch cultivation In a bioreactor under the pH stat (pH 6) conditions. It was observed that conductivity measurement were suitable for biomass characterisation under highly dynamic uncontrolled shake flask cultivation conditions. However, if the acid/alkali feeding is done for pH control the conductivity measurement could not be applied. On the other hand the NADH fluorescence measurement allowed online-in situ biomass monitoring of rather heterogenous plant cell suspension cultures in bioreactor even under the most desirable pH stat conditions.

Blood Gas Management of a Membrane Oxygenator During Cardiac Surgery with Deep Hypothermic Circulatory Arrest (막형산화기에 의한 저체온 순환정지 심장수술시 혈액가스 조절)

  • Kim, W. G.;Lim, C.;Baek, Y. H.
    • Journal of Biomedical Engineering Research
    • /
    • v.19 no.3
    • /
    • pp.279-284
    • /
    • 1998
  • Deep hypothermic circulatory arrest(DHCA), in which systemic temperatures of 2$0^{\circ}C$ or less are used to allow temporary cessation of the circulation, is an useful adjunct in cardiac surgery. Because man in natural circumstances is never exposed to the extreme hypothermic condition, however, one of the controversial aspects is appropriate blood gas management($\alpha$STAT versus PH-STAT) during DHCA. This study aims to compare $\alpha$STAT with PH-STAT management for control of blood gases in experimental cardiopulmonary bypass(CPB) circuits with a membrane oxygenator. Fourteen young pigs were assigned to one of two strategies of gas manipulation. After a median sternotomy, CPB was established. Core cooling was initiated and continued until nasopharyngeal temperature fell below 2$0^{\circ}C$. The flow rate was set at 2,500 ml/min. Once their temperatures were below 2$0^{\circ}C$, the animals were subjected to circulatory arrest for 40mins. During cooling, blood gas was maintained according to either $\alpha$$\alpha$STAT or pH-STAT strategies. After DHCA, the body was rewarmed to normal body temperature. Arterial blood gases were measured before the onset of CPB, before cooling, before DHCA, at the point of 27$^{\circ}C$ during re-warming, on completion of re-warming. Cooling time was significantly shorter in $\alpha$-STAT than PH-STAT strategy, while there was no significant differences in rewarming time between two groups. Carbon dioxide was added between 5.5 and 3.0% in PH-STAT, while no carbon dioxide was added in $\alpha$STAT management. Amounts of oxygen administration were gradually lowered as temperature decreased. In this way, criteria of PH, PaCO, and PaO adjustments were satisfied in both $\alpha$STAT and PH-STAT management groups.

  • PDF

Increase of Cell Concentration by the Automatic Addition of Glucose and Ammonium to an Alcohol distillery Wastewater Reutilized for Cultivating a Baker's Yeast : Automatic Addition of Ammonium with pH-stat (알콜증류폐액을 이용한 빵효모배양에서 Glucose와 Ammonium의 자동첨가에 의한 종균 : pH-stat 방법에 의한 Ammonium의 자동첨가)

  • 이형춘
    • KSBB Journal
    • /
    • v.15 no.2
    • /
    • pp.134-138
    • /
    • 2000
  • Addition of carbon and nitrogen source to an alcohol distillery wastewater was tried to increase the cell concentration of a b baker's yeast cultivated in that wastewater. Carbon was found to be primary limiting nutrient and nitrogen secondary limiting o one. Glucose addition increased the cell concentration 1.3 times higher than no addition, and both glucose and $(NH_4)_2S0_4$ a addition did 5.8 times. A fed-batch cultivation by the automatic addition of glucose and ammonium was executed. Added g glu$\infty$se was automatically controlled to low concentration by a method using DO as control parameter. Ammonium was a automatically added as NH40H used as pH $\infty$ntrol agent after initiating glucose addition. By this simple cultivation method t the cell concentration $\infty$내d be efficiently increased from 2.6g/L to 12.0g/L, and maximum specific growth rate and biomass y yield to glu$\infty$se were $0.18hr^{-1}$ and about 0.54g/g respectively. By increasing cell concentration, COD of the wastewater m media could be additionally reduced by about 22%.

  • PDF

Anti-inflammatory Effect of Morinda citrifolia on LPS-induced Inflammation in RAW 264.7 Cells Through the JAK/STAT Signaling Pathway (JAK/STAT 신호전달 경로를 통한 LPS 유도 RAW 264.7 세포의 염증에 대한 노니의 항염증 효과)

  • Jo, Beom Gil;Bang, In Seok
    • Journal of Life Science
    • /
    • v.32 no.2
    • /
    • pp.125-134
    • /
    • 2022
  • This study investigated whether or not the major bioactive compounds of Noni (Morinda citrifolia) are involved in anti-inflammatory activity through the JAK/STAT upper signaling pathway in RAW 264.7 cells. The experimental results show that the M. citrifolia ethyl acetate fraction (Mc-EtOAc) obtained by sequential fractionation with organic solvents from the plant's dried fruits exhibits the highest antioxidant activity. In addition, the cytoprotective effects of Mc-EtOAc against H2O2-induced oxidative stress in the RAW 264.7 cells suppressed cytotoxicity in a dose-dependent manner. The group pretreated with Mc-EtOAc at a concentration of 240 ㎍/ml showed higher cell viability of 84.5%, compared to 71.6% in the LPS-treated group, and LPS-induced NO production decreased to half the amount in the positive control group. Mc-EtOAc treatment also led to a significant dose-dependent reduction in iNOS expression. Although COX-2 expression was increased by 300% following LPS induction, it was significantly decreased in a dose-dependent manner by pretreatment with Mc-EtOAc at concentrations of 120 and 240 ㎍/ml. An inhibition of the mRNA expression of pro-inflammatory cytokines IL-1β and TNF-α was observed. The investigation also revealed that the phosphorylation levels of pJAK1 and pSTAT3 in LPS-induced RAW 264.7 cells were significantly reduced by Mc-EtOAc treatment.

Estimation of Residual Biomass, PHB, and Nutrient Concentrations by Supplied Amount of Ammonia Solution in Fermentation of Alcaligenes latus

  • Lee, Yong-Woo;Tsuneo Yamane
    • Journal of Microbiology and Biotechnology
    • /
    • v.9 no.5
    • /
    • pp.554-561
    • /
    • 1999
  • A novel estimation method was investigated for determining the concentrations of residual biomass, poly-3-hydroxybutyrate (PHB), and main nutrients including carbon and nitrogen sources, phosphate, and mineral ions from the supplied amount of ammonia solution used for a pH-control solution and nitrogen source in a PHB fermentation. The estimation equations for a batch culture and a fed-batch culture were derived from the relationship between the growth rate of residual biomass and the feed rate of the pH-control solution, and then were applied to the batch culture and the fed-batch cultures of Alcaligenes latus. This method was successfully applied to estimate the concentrations of residual biomass, PHB, and nutrients.

  • PDF

Increasing Cell Concentration by the Automatic Addition of Glucose, Ammonium and Phosphate in the Cultivation of a Baker′s Yeast in Alcohol Distillery Wastewater (알콜증류폐액을 이용한 빵효모배양에서 포도당, 암모늄 및 인산의 자동첨가에 의한 증균)

  • 이형춘
    • KSBB Journal
    • /
    • v.18 no.3
    • /
    • pp.197-201
    • /
    • 2003
  • Automatic addition of glucose, ammonium and phosphate to alcohol distillery wastewater and their control at low concentrations have been carried increase the cell concentration of a baker's yeast cultivated in the wastewater. Glucose was automatically added using dissolved oxygen as the control parameter, and maintained below 300 mg/L. Ammonium was automatically added by a pH-stat method and maintained in the low range of 12.6~17.4 mM. An automated FIA system, which used an ascorbic acid-based method was developed for the automatic analysis nad addition of phosphate. With this system, the phosphate concentration was succesfully analysed and controlled afrer 19.4 hr in the range 23.3~43.4 mg/L. The cell concentration was increased by 33.0-fold by the addition of these three nutrients. The overall specific growth rate of the yeast was 0.19 $hr^{-1}$.

Development of a Novel Medium with Chinese Cabbage Extract and Optimized Fermentation Conditions for the Cultivation of Leuconostoc citreum GR1 (폐배추 추출물을 이용한 Leuconostoc citreum GR1 종균 배양용 최적 배지 및 배양 조건 개발)

  • Moon, Shin-Hye;Chang, Hae-Choon;Kim, In-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.42 no.7
    • /
    • pp.1125-1132
    • /
    • 2013
  • In the kimchi manufacturing process, the starter is cultured on a large-scale and needs to be supplied at a low price to kimchi factories. However, current high costs associated with the culture of lactic acid bacteria for the starter, have led to rising kimchi prices. To solve this problem, the development of a new medium for culturing lactic acid bacteria was studied. The base materials of a this novel medium consisted of Chinese cabbage extract, a carbon source, a nitrogen source, and inorganic salts. The optimal composition of this medium was determined to be 30% Chinese cabbage extract, 2% maltose, 0.25% yeast extract, and $2{\times}$ salt stock (2% sodium acetate trihydrate, 0.8% disodium hydrogen phosphate, 0.8% sodium citrate, 0.8% ammonium sulfate, 0.04% magnesium sulfate, 0.02% manganese sulfate). The newly developed medium was named MFL (medium for lactic acid bacteria). After culture for 24 hr at $30^{\circ}C$, the CFU/mL of Leuconostoc (Leuc.) citreum GR1 in MRS and MFL was $3.41{\times}10^9$ and $7.49{\times}10^9$, respectively. The number of cells in the MFL medium was 2.2 times higher than their number in the MRS media. In a scale-up process using this optimized medium, the fermentation conditions for Leuc. citreum GR1 were tested in a 2 L working volume using a 5 L jar fermentor at $30^{\circ}C$. At an impeller speed of 50 rpm (without pH control), the viable cell count was $8.60{\times}10^9$ CFU/mL. From studies on pH-stat control fermentation, the optimal pH and regulating agent was determined to be 6.8 and NaOH, respectively. At an impeller speed of 50 rpm with pH control, the viable cell count was $11.42{\times}10^9(1.14{\times}10^{10})$ CFU/mL after cultivation for 20 hr - a value was 3.34 times higher than that obtained using the MRS media in biomass production. This MFL media is expected to have economic advantages for the cultivation of Leuc. citreum GR1 as a starter for kimchi production.

Increased Poly(3-Hydroxybutyrate) Accumulation in Recombinant Escherichia coli from Whey by Agitation Speed Control

  • Kim, Beom-Soo;Brian K. O'Neill;Lee, Sang-Yup
    • Journal of Microbiology and Biotechnology
    • /
    • v.10 no.5
    • /
    • pp.628-631
    • /
    • 2000
  • The timing of poly(3-Hydroxybutyrate) (PHB) biosynthesis was controlled by varying the agitation speed of a stirred tank fermentor during the pH-stat fed-batch culture of recombinant Escherichia coli strain GCSC 6576 harboring pSYL107. Using a concentrated whey solution containing ca. 200 g/l lactose as the nutrient feed, the PHB content was only 57% after 35h due to volumetric limitation of the fermentor. However, by limiting the oxygen by maintaining the agitation speed at 300 rpm, the final PHB content increased to 70% after 70h with a cell concentration of 15 g/l. When the agitation speed was increased up to 500 rpm, a cell concentration of 31 g/l with 80% PHB was obtained after 52h. A further increase in the maximum agitation speed increased the cell concentration, PHB concentration, and PHB productivity, however, the PHB content decreased to 56-58%.

  • PDF

Effects of β-Glucan on the Release of Nitric Oxide by Macrophages Stimulated with Lipopolysaccharide

  • Choi, E.Y.;Lee, S.S.;Hyeon, J.Y.;Choe, S.H.;Keum, B.R.;Lim, J.M.;Park, D.C.;Choi, I.S.;Cho, K.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.29 no.11
    • /
    • pp.1664-1674
    • /
    • 2016
  • This research analyzed the effect of ${\beta}$-glucan that is expected to alleviate the production of the inflammatory mediator in macrophagocytes, which are processed by the lipopolysaccharide (LPS) of Escherichia. The incubated layer was used for a nitric oxide (NO) analysis. The DNA-binding activation of the small unit of nuclear factor-${\kappa}B$ was measured using the enzyme-linked immunosorbent assay-based kit. In the RAW264.7 cells that were vitalized by Escherichia coli (E. coli) LPS, the ${\beta}$-glucan inhibited both the combatant and rendering phases of the inducible NO synthase (iNOS)-derived NO. ${\beta}$-Glucan increased the expression of the heme oxygenase-1 (HO-1) in the cells that were stimulated by E. coli LPS, and the HO-1 activation was inhibited by the tin protoporphyrin IX (SnPP). This shows that the NO production induced by LPS is related to the inhibition effect of ${\beta}$-glucan. The phosphorylation of c-Jun N-terminal kinases (JNK) and the p38 induced by the LPS were not influenced by the ${\beta}$-glucan, and the inhibitory ${\kappa}B-{\alpha}$ ($I{\kappa}B-{\alpha}$) decomposition was not influenced either. Instead, ${\beta}$-glucan remarkably inhibited the phosphorylation of the signal transducer and activator of transcription-1 (STAT1) that was induced by the E. coli LPS. Overall, the ${\beta}$-glucan inhibited the production of NO in macrophagocytes that was vitalized by the E. coli LPS through the HO-1 induction and the STAT1 pathways inhibition in this research. As the host immune response control by ${\beta}$-glucan weakens the progress of the inflammatory disease, ${\beta}$-glucan can be used as an effective immunomodulator.