Zhang Shouqin

Note: Effect of High Hydrostatic Pressure on Extraction of Flavonoids in Propolis

The effect of high hydrostatic pressure (HHP) on the extraction of flavonoids components (chrysin and galangin) of propolis was studied. The experimental results showed that HHP did not modify their molecular structure. The extraction yields of flavonoids compounds by HHP for 1min were even higher than those obtained with extraction at room temperature (ERT) for 7 days. These excellent results showed a bright prospect for extraction of flavonoids components from propolis.

The mechanical properties of polyaniline Electrorheological fluid

The better mechanical properties of Electrorheological fluid (ERF) are the key for its successful engineering application. The mechanical characteristics of the polyaniline (PAn) ERF were tested on modified TA Instrument AR500 Rheometer in this paper. The experimental results of the steady flow show that the shear stress produced by ERF increased with the rise in electric field strength and concentration of volume ratio. The curves of dynamic yield stress vs. electric field strength shows that the relationship between them approximately takes on exponential rule, and the dynamic yield stress increased with the rise in concentration of volume ratio. Dynamic oscillatory test results show that the ER effect will be significantly enhanced with the rise in electric field strength and will be apparently inhibited with the rise in vibration amplitude; while the effect of vibration frequency on dynamic properties of ERF is almost neglected.

Appliction of membrane technology on deer blood albumin separation

Deer blood albumin was first separated with membrane technology. Microfiltration as pretreatment methods greatly improved the separation efficiency of ultrafiltration. The major factors of ultrafiltration such as pressure, temperature, PH and material-liquid total protein were investigated to evaluate the effect on membrane flux. The optimal operating condition was 0.2 MPa of operating pressure, 35 °C of operating temperature, 60 min of operating time, PH 6.3, 23.8 mg/mL of material-liquid total protein concentration. Albumin content in separated samples was above 80% under the optimal operating condition. The contaminative membrane was cleaned with different methods. The best method was distilled water for 0.5 h, 250 ppm NaClO (35∼40 °C) alkaline solution for 1 h, then 0.2% SDS alkaline solution (35∼40 °C) for 1 h, and finally distilled water washing until neutrality. An excellent membrane flux was achieved and water flux recovery was 94.7%.

Detection and quantitation of insulin-like growth factor-1 in velvet antler by an enzyme-linked immunosorbent assay

An enzyme-linked immunosorbent assay (ELISA) was used to detect the content of insulin-like growth factor-1 (IGF-1) in velvet antler water extract. The ELISA was validated with respect to parallelism, recovery, intra-assay variation, and inter-assay variation. The practical working range of detection was estimated to be 0.8 to 200 ng/mL, and the recovery was 96.7% or more. The effect of sample matrix was assessed by serial dilution. The result indicated that this ELISA method is a reliable, safe, and cost-effective tool for determination of IGF-1 content in velvet antler and serum.