1.Study on Preparation and in vitro Release Property of Diosmin Gel
Mingyu CUI ; Yuanyuan LIU ; Qimeng HU ; Feng GUAN ; Yingli MA
China Pharmacy 2019;30(20):2778-2782
OBJECTIVE: To optimize the formulation of Diosmin gel and to investigate its in vitro release property. METHODS: Diosmin gel were prepared by using Carbomer 940 as matrix. Using accumulative release rate as index, with the amount of Carbomer 940, ethanol, acetone and pH as factors, L9(34) orthogonal test was conducted. The formulation of Diosmin gel was optimized and validated. Using Diosmin ointment as reference, dialysis bag diffusion method was used to investigate in vitro release property of Diosmin gel prepared by optimal formulation. RESULTS: The optimal formulation of Diosmin gel included Carbomer 940 1.5 g, ethanol 15 mL, glycerol 8 g, pH 6. The gel prepared with optimal formulation was sticky brown-yellow semi solid, and had good coating and spreading properties. The average accumulative release rate (2 h) was (12.67±0.12)%. Results of drug release test showed that Diosmin gel released rapidly within 12 h, then gradually slowed down. The accumulative release rates were (71.93±0.42)% (12 h) and (80.47±0.54)% (24 h), drug release of which were in line with Higuchi equation. Diosmin ointment was released slowly. The accumulative release rates were (41.74±0.18)% (12 h) and (62.63±0.59)% (24 h). Drug release of it were in line with first-order equation. CONCLUSIONS: The formulation of Diosmin gel is optimized successfully. Prepared Diosmin gel has good drug release property.
2.Expression, purification, characterization and application of α-amino acid ester acyltransferase from recombinant Escherichia coli.
Pengfei LIU ; Qimeng LU ; Xueqin HU ; Xuewen HOU ; Hongbin ZHANG
Chinese Journal of Biotechnology 2018;34(7):1169-1177
α-Amino acid ester acyltransferase (Aet) catalyzes the L-alanyl-L-glutamine forming reaction from L-alaine methylester hydrochloride and L-glutamine. In this study, the recombinant Escherichia coli saet-QC01 was used to express the α-amino acid acyltransferase, and its expression conditions were optimized. The recombinant protein was separated and purified by Ni-NTA affinity chromatography, and its enzymatic properties and catalytic applications were studied. The induction conditions suitable for enzyme production optimized were as follows: The temperature was 20 ℃, the induction stage (OD₆₀₀=2.0-2.5), IPTG concentration was 0.6 mmol/L, induction time was 12 h. The optimal reaction conditions of α-amino acid acyltransferase were 27 ℃, pH 8.5, it was most stable between pH 7.0 and 8.0 and relatively stable in an acidic environment, and low concentration of Co²⁺ or EDTA could promote the enzyme activity. Under optimal reaction conditions, 600 mmol/L of L-alaine methylester hydrochloride and 480 mmol/L of L-glutamine, the yield of L-alanyl-L-glutamine reached 78.2 g/L and productivity of 1.955 g/L/min, the conversion rate reached 75.0%. α-Amino acid ester acyltransferase has excellent acid-basei resistance, high catalytic efficiency. These characteristics suggest its application prospects in the industrial production.
3. Clinical significance of serum high mobility group box-1 protein in patients with acute cholangitis
Xiaodong SHEN ; Xubo WU ; Zhiqiu HU ; Qimeng CHANG ; Biao YANG ; Ziping ZHANG
Chinese Journal of General Surgery 2019;34(10):883-886
Objective:
To analyze perioperative serum high mobility group box-1 protein (HMGB1) levels in patients with acute cholangitis and its clinical significance.
Methods:
118 cases of choledocholithiasis with acute cholangitis were retrospectively analyzed, admittd in Minhang Hospital from Jan 2017 to Dec 2017. Enzyme linked immunosorbent assay (ELISA) was used to detect serum HMGB1 levels before and after ERCP. The relationship between serum HMGB1 levels and severity of the disease was analyzed.
Results:
The serum HMGB1 levels in the healthy controls, mild cholangitis group, moderate cholangitis group and severe cholangitis group were(1.74±0.79) μg/L, (9.19±4.86) μg/L, (12.62±4.13) μg/L, (18.02±3.84) μg/L, respectively. The serum HMGB1 levels were significantly different in these four groups (