1.Identification and Simulation Mutation of a High-productive Strain of Poly(?-glutamic acid) Independent of Glutamic Acid
Xiu-Lin SHU ; Qing-Shan SHI ; Jing FENG ; You-Sheng OUYANG ; Yi-Ben CHEN ;
Microbiology 1992;0(05):-
A high productive poly ?-glutamic acid(?-PGA) strain PGA-N in a culture medium containing no L-glutamine was isolated from fermentation products.With the following identifications of colony mor-phology,physiological and biochemistry experiments,and genetics,the strain PGA-N was classified as a Bacillus licheniformis.According to the product environment,the base culture medium having no L-glutamine was simulated.In order to enhance the production of the strain PGA-N,the fermentation condi-tions,such as carbon source,nitrogen source,were optimized and the ?-glutamic acid production reached 5.16 g/L after getting the optimum formulation of this culture medium.PGA-N was mutagenized with com-bination of NTG and UV.A mutant PGA-N-C10 was screened which PGA production was increased from 5.16 g/L to 8.82 g/L.The study also investigated the effects of agitation speed on the cell biomass,?-PGA production and the ?-PGA molecular weight.The ?-PGA yield of PGA-N-C10 was as high as 11.00 g/L when the agitation speed was 400 r/min.
2.Research Progress on the Polyphasic Taxonomy of Acetic Acid Bacteria
Jing FENG ; Qing-Shan SHI ; You-Sheng OUYANG ; Yi-Ben CHEN ;
Microbiology 2008;0(09):-
Acetic acid bacteria are Gram-negative,obligate aerobic bacteria that have the ability to incompletely oxidize alcohols or sugars to organic acids as end products. The taxonomy of acetic acid bacteria has undergone many changes in the last 30 years. The early classification systems for these bacteria were based on morphological and biochemical characteristics. Today,the acetic acid bacteria are classified as the consensus result of a polyphasic analysis,combining phenotypic,chemotaxonomic and genotypic data. This paper reviewed the polyphasic taxonomy of acetic acid bacteria,mainly introduced the current classification of acetic acid bacteria,then discussed the application of phenotypic,chemotaxonomic and genotypic method in the taxonomy of acetic acid bacteria.
3.Effect of quercetin on colon contractility and L-type Ca(2+) channels in colon smooth muscle of guinea-pig.
Wei-Feng HUANG ; Shou OUYANG ; Shi-Ying LI ; Yan-Fei LIN ; Hui OUYANG ; Hui ZHANG ; Chun-Jing LU
Acta Physiologica Sinica 2009;61(6):567-576
The aim of the present study was to investigate the effects of quercetin on colon contractility and voltage-dependent Ca(2+) channels in the single smooth muscle cell isolated from the proximal colon of guinea-pig and to clarify whether its effect on L-type Ca(2+) current (I(Ca,L)) would be related to its myorelaxing properties. Colon smooth muscle strips were used to take contractile tension recordings. Smooth muscle cells were freshly isolated from the proximal colon of guinea-pig by means of papain treatment. I(Ba,L) (barium instead of calcium as current carrier) was measured by using whole-cell patch-clamp techniques. The results showed that quercetin relaxed colon muscle strips in a concentration-dependent manner and antagonized the contractile effect of acetylcholine and neostigmine. Preincubation with indomethcin [cyclooxygenase (COX) inhibitor] and methylene blue [guanylate cyclase (GC) inhibitor] significantly attenuated the relaxing effect of quercetin, respectively. Quercetin increased I(Ba,L) in a concentration- [EC(50)= (7.59+/-0.38) mumol/L] and voltage-dependent pattern, and shifted the maximum of the current-voltage curve by 10 mV in the depolarizing direction without modifying the threshold potential for Ca(2+) influx. Quercetin shifted the steady-state inactivation curve toward more positive potentials by approximately 3.75 mV without affecting the slope of activation and inactivation curve. H-89 (PKA inhibitor) abolished quercetin-induced I(Ba,L) increase, while cAMP enhanced the quercetin-induced I(Ba,L) increase. The patch-clamp results proved that quercetin increased I(Ba,L) via PKA pathway. It is therefore suggested that the relaxing effect of quercetin attributes to the interaction of GC and COX stimulation, as well as the antagonism effect on acetylcholine, which hierarchically prevails over the increase in the Ca(2+) influx to be expected from I(Ca,L) stimulation.
Animals
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Calcium Channels, L-Type
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metabolism
;
Cells, Cultured
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Colon
;
drug effects
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Guinea Pigs
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Muscle Contraction
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Myocytes, Smooth Muscle
;
drug effects
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Patch-Clamp Techniques
;
Quercetin
;
pharmacology
4.Studies on pharmacokinetics of hydroxysafflor yellow A in Carthamus tinctorius and its compound preparation in rat.
Jianming TANG ; Zhen OUYANG ; Xu FENG ; Jing FANG ; Xu CAO
China Journal of Chinese Materia Medica 2011;36(16):2246-2249
OBJECTIVETo develop a RP-HPLC method for the determination of the concentration of hydroxysafflor yellow A in rat plasma, to study the pharmacokinetics of Carthamus tinctorius extration and Naodesheng tablet, and to investigate the effect of other components on the pharmacokinetics of hydroxysafflor yellow A.
METHODThe rats were orally treated with Carthamus tinctorius extration and Naodesheng capsule respectively. Blood samples were collected in heparinized eppendorf tube via the oculi chorioideae vein. Plasma was separated by centrifugation at 10 000 r x min(-1) for 10 min, and two-times methanol in volume was added to deposit proteins. After centrifugation, the upper liquid was transferred to filter. The concentration of hydroxysafflor yellow A in serum was determined by RP-HPLC. The stationary phase was C18, and methanol-acetonitrile-0.7% orthophosphoric acid (26: 2:72) was taken as the mobile phase, A UV detector was used at 403 nm. The pharmacokinetic parameters were calculated with 3p97 program.
RESULTA good linear relationship of hydroxysafflor yellow A was obtained in the range of 0.03 and 2.56 mg x L(-1), the lowest limit of determination was 10 microg x L(-1), and the lowest limit of quantitation was 30 microg x L(-1). The mean recoveries were (99.3 +/- 1.4)%, (92.8 +/- 1.8)%, (98.4 +/- 2.0)% for high, middle, low concentrations of the samples respectively. The plasma concentration-time curves of hydroxysafflor yellow A were fitted with two-compartments model. The AUC)0-t), AUC(0-infinity), C(max) and T(max) of hydroxysafflor yellow A were increased in the Naodesheng group, compared with 50 mg x kg(-1) C. tinctorius extract group.
CONCLUSIONThe HPLC method was selective, accurate and sensitive. The results indicated that the other herbs improved the absorption of hydroxysafflor yellow A and increased the bioavailability of hydroxysafflor yellow A significantly.
Animals ; Biological Availability ; Carthamus tinctorius ; chemistry ; Chalcone ; analogs & derivatives ; pharmacokinetics ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; pharmacokinetics ; Male ; Plant Extracts ; pharmacokinetics ; Quinones ; pharmacokinetics ; Rats ; Rats, Sprague-Dawley
5.Isolation and Identification of BLN-2 Producing Poly-?-Glutamic Acid and Studies on Its Solid-state Fermentation
Jing FENG ; Qing-Shan SHI ; Xiu-Lin SHU ; Xiao-Ping LIN ; You-Sheng OUYANG ; Yi-Ben CHEN ;
Microbiology 2008;0(09):-
A poly-?-glutamic acid producing strain--BLN-2, was isolated from the soybean products. According to the biochemical characteristics and 16S rRNA, the strain was identified as Bacillus subtilis. Using soybeans as culture, the solid-state fermentation conditions of BLN-2 have been studied. The results showed that the optimal carbon and nitrogen sources of BLN-2 were glucose, fructose, NaNO3 and KNO3, respectively. The orthrogonal experiments showed, when the final concentration of the fructose which was added to the soybean culture was 0.5%, the glucose, NaNO3 and KNO3 final concentraion were 2.0%, the production of ?-PGA was the highest--89.05 g/kg. It is 48.42% higher than other comparable soybean medium under the same conditions.
6.Effect of perioperative intestinal probiotics on intestinal flora and immune function in patients with colorectal cancer.
Dajian ZHU ; Xiaowu CHEN ; Jinhao WU ; Yongle JU ; Jing FENG ; Guangsheng LU ; Manzhao OUYANG ; Baojun REN ; Yong LI
Journal of Southern Medical University 2012;32(8):1190-1193
OBJECTIVETo investigate the effect of perioperative application of intestinal probiotics to substitute oral intestinal antimicrobial agents on intestinal flora and immune function in surgical patients with colorectal cancer.
METHODSSixty patients with colorectal cancer undergoing elective laparoscopic radical surgery were randomized to receive preoperative bowel preparation using oral intestinal antimicrobial agents (n=20) or using oral intestinal probiotics (Jinshuangqi Tablets, 2.0 g, 3 times daily) since the fifth day before the operation and at 24 h after the operation for 7 consecutive days. Upon admission and 7 days after the operation, fecal samples and fasting peripheral venous blood were collected from the patients to examine the intestinal flora and serum levels of interleukin-2 (IL-2), IgA, IgG, and IgM, NK cell activity, T lymphocytes subsets CD3(+), CD4(+), CD8(+) and CD4(+)/CD8(+) ratio.
RESULTSAt 7 days after the operation, the patients receiving probiotics showed significantly increased counts of intestinal Bifidobacterium, Lactobacillus, and Enterococcus (P<0.05) and significantly lowered counts of Escherichia coli and Staphylococcus aureus (P<0.05). The serum levels of IL-2, IgA, IgG and IgM as well as CD4(+) cell percentage all increased significantly in probiotics group compared with those in patients with conventional intestinal preparation (P<0.05).
CONCLUSIONSPerioperative application of intestinal probiotics to replace preoperative oral intestinal antimicrobial agents can effectively correct intestinal flora imbalance and improve the immune function of surgical patients with colorectal cancer.
Aged ; Bifidobacterium ; Colorectal Neoplasms ; immunology ; microbiology ; Female ; Humans ; Intestines ; microbiology ; Intraoperative Period ; Male ; Middle Aged ; Premedication ; Probiotics ; therapeutic use ; Prospective Studies ; Single-Blind Method
7.Optimization of composition and concentration for lyophlizing protectant of human red blood cells.
Lin-Feng CHEN ; Jing-Han LIU ; Xi-Lin OUYANG ; Yuan ZHUANG ; Ji CHE ; Yang YU
Journal of Experimental Hematology 2009;17(5):1368-1372
This study was purposed to investigate the effect of different compositions and concentrations of lyophilizing protectants on recovery of RBCs and hemoglobin (Hb) after rehydration of lyophilized RBCs. The RBC lyophilizing protectants composed of a series concentrations of PVP, trehalose and different osmotic protectants were applied for protecting lyophilizing process of RBCs, the recovery of RBCs and Hb after rehydration of lyophilized RBCs was detected. The results showed that there were significant differences in loss ratio of RBCs between protectants composed of different compositions and concentrations (p<0.05 or p<0.01). The loss ratio of RBCs in protectant containing 30% PVP40, 150 mmol/L trehalose and 2% BSA was minimum (0.02%), the loss ratio of RBCs in protectant containing 6% PVP 360, 100 mmol/L trehalose and 2% BSA was maximum (0.27%). The difference of effect between 150 and 50 mmol/L trehalose was statistically significant (p<0.01). The recovery rates of RBCs and Hb in protectants contained PVP40 of different concentrations were different after rehydration of lyophilized RBCs. The protectant containing 15% PVP40, 150 mmol/L trehalose and 2% BSA showed optimal protective efficacy for lyophilized RBCs, the recovery rates of RBCs and Hb were 61.29+/-4.11% and 62.49+/-5.91% respectively, which were statistically different from other protectants (p<0.01). The protectants containing glycerol displayed best efficiency in lyophilization too, the recovery rates of RBCs and Hb were 65.97+/-4.52% and 67.24+/-5.94%, respectively. It is concluded that the protectants composed of 0.8 mol/L glycerol, 15% PVP40, 150 mmol/L trehalose and 2% BSA (pH 7.3 ) may be used as the protectant lyophilizing human RBCs in future study.
Blood Preservation
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methods
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Cryoprotective Agents
;
administration & dosage
;
analysis
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Erythrocytes
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Freeze Drying
;
methods
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Humans
;
Trehalose
;
administration & dosage
;
analysis
8.Mechanism of improving effect of losartan on insulin sensitivity of non-insulin-dependent diabetes mellitus rats.
Yong WU ; Jing-Ping OUYANG ; Yun-Feng ZHOU ; Ke WU ; De-Hai ZHAO ; Chong-Yuan WEN
Acta Physiologica Sinica 2004;56(4):539-549
The specific inhibition of angiotensin II action at AT(1) receptors by losartan has been shown to decrease peripheral insulin resistance in type 2 diabetic patients and animal models. We examined the effect of losartan on the expression of insulin receptor substrate 1 (IRS-1), protein kinase B (PKB) and glucose transporter 4 (GLUT4), as well as the phosphorylation status of IRS-1 and the association between IRS-1 and phosphatidylinositol (PI) 3-kinase in skeletal muscle from fat-fed and-streptozotocin (STZ)-treated rats, an animal model of type 2 diabetes mellitus. In addition, the effects of losartan on GLUT4 translocation in muscle cells and on insulin sensitivity were also evaluated. Muscle tissues were isolated from male losartan-treated and untreated normal or non-insulin-dependent diabetes mellitus (NIDDM) rats with a dose of 4 mg/kg per day for 6 weeks. Oral administration of losartan improved insulin sensitivity, which was determined by an oral glucose tolerance test (OGTT). In skeletal muscles, the protein levels of IRS-1, PKB and GLUT4 in NIDDM rats were not significantly different from those of the control rats, and they were not affected by losartan. The levels of IRS-1 tyrosine phosphorylation, PI 3-kinase activity associated with IRS-1 and PKB activation after stimulation with insulin in muscle tissue of NIDDM rats were significantly decreased (P<0.01) compared with those in the control rats, while they were not increased by losartan. Losartan had a major effect on GLUT4 translocation in myocytes, as it significantly increased (P<0.05) the insulin-induced amounts of GLUT4 in plasma membrane (PM) and T-tubules (TT) in myocytes from NIDDM rats. Consistent with these results, the plasma glucose level in losartan-treated NIDDM rats was decreased (P<0.05) compared with that in untreated NIDDM rats. Our results suggest that losartan may exert beneficial effects on insulin resistance by increasing the translocation of GLUT4 in muscle tissue, which is probably associated with a non-PI 3-kinase-dependent mechanism.
Animals
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Diabetes Mellitus, Experimental
;
blood
;
drug therapy
;
Diabetes Mellitus, Type 2
;
blood
;
drug therapy
;
physiopathology
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Glucose Transporter Type 4
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Insulin Receptor Substrate Proteins
;
Insulin Resistance
;
Losartan
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pharmacology
;
therapeutic use
;
Male
;
Monosaccharide Transport Proteins
;
biosynthesis
;
genetics
;
Muscle Proteins
;
biosynthesis
;
genetics
;
Muscle, Skeletal
;
metabolism
;
Phosphoproteins
;
biosynthesis
;
genetics
;
Protein-Serine-Threonine Kinases
;
biosynthesis
;
genetics
;
Proto-Oncogene Proteins
;
biosynthesis
;
genetics
;
Proto-Oncogene Proteins c-akt
;
Rats
;
Rats, Sprague-Dawley
9.Preliminary study on rehydrated conditions for lyophilized human red blood cells.
Lin-Feng CHEN ; Jing-Han LIU ; De-Qing WANG ; Xi-Lin OUYANG ; Yuan ZHUANG ; Ji CHE ; Hui LI
Journal of Experimental Hematology 2009;17(6):1582-1587
The objective of this study was to investigate the effect of different rehydration conditions on recovery of the lyophilized red blood cells (RBC) so as to optimize the RBC rehydration. The different conditions, including different rehydration solution, the rehydration temperature, volume change rate of the lyophilized RBC rehydrated by the vapor firstly, were studied, the recovery rate and change of physiological and biochemical properties of the rehydrated RBC were detected. The results indicated that the solution of 10% (w/v) PVP40 in PBS showed the best effect, and the RBC recovery rate increased with increasing of rehydration temperature, and the optimal temperature of rehydration was at 37 degrees C. Pre-rehydration in condition of vapor could raise the RBC recovery rate, and promote the MCV and RDW to close to index of the fresh RBC, the deformability of the rehydrated RBC was no serious as compared with RBC preserved in conventional condition, but the activity level of ATP, G-6-PD, SOD, 2, 3-DPG of the rehydrated RBC less decreased. It is concluded that the optimal rehydration conditions for lyophilized RBC are pre-rehydration in the 37 degrees C with vapor firstly, PBS + 10% (w/v) PVP40 rehydration solution and rehydration temperature at 37 degrees C, but the protection of RBC membrane needs to be furtherly studied.
Blood Preservation
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methods
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Erythrocyte Count
;
Erythrocytes
;
Freeze Drying
;
methods
;
Humans
;
Rehydration Solutions
;
Temperature
10.Optimization of trehalose loading in red blood cells before freeze-drying.
Yuan ZHUANG ; Jing-Han LIU ; Xi-Lin OUYANG ; Lin-Feng CHEN ; Ji CHE
Journal of Experimental Hematology 2007;15(2):412-416
The key points for better protection of trehalose in freeze-drying red blood cells (RBCs) are to resolve non-osmosis of trehalose to red blood cells and to make cytoplasmic trehalose to reach effective concentration. This study was aimed to investigate the regularity of loading RBCs with trehalose, screen out optimal loading condition and evaluate the effect of trehalose on physico-chemical parameters of RBCs during the period of loading. The cytoplasmic trehalose concentration in red blood cells, free hemoglobin and ATP level were determined at different incubation temperatures (4, 22 and 37 degrees C), different trehaolse concentrations (0, 200, 400, 600, 800 and 1000 mmol/L) and different incubation times (2, 4, 6, 8 and 10 hours), the cytoplasmic trehalose, free hemoglobin (FHb), hemoglobin (Hb) and mean corpuscular volume (MCV) in fresh RBCs and RBCs stored for 72 hours at 4 degrees C were compared, when loading condition was ensured. The results showed that with increase of incubation temperature, time and extracellular trehalose concentration, the loading of trehalose in RBCs also increased. Under the optimal loading condition, cytoplasmic trehalose concentration and free hemoglobin level of fresh RBCs and RBCs stored for 72 hours at 4 degrees C were 65.505 +/- 6.314 mmol/L, 66.2 +/- 5.002 mmol/L and 6.567 +/- 2.568 g/L, 16.168 +/- 3.922 g/L respectively. It is concluded that the most optimal condition of loading trehalose is that fresh RBCs incubate in 800 mmol/L trehalose solution for 8 hours at 37 degrees C. This condition can result in a efficient cytoplasmic trehalose concentration. The study provides an important basis for long-term preservation of RBCs.
Biological Transport, Active
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drug effects
;
Blood Preservation
;
methods
;
Cryopreservation
;
methods
;
Cryoprotective Agents
;
metabolism
;
pharmacology
;
Erythrocyte Membrane
;
metabolism
;
Erythrocytes
;
Freeze Drying
;
Humans
;
Osmotic Fragility
;
Temperature
;
Time Factors
;
Trehalose
;
metabolism
;
pharmacology