Optimization of extraction tower structure and extraction conditions for lincomycin separation

Lincomycin is a widely used aminoglycoside antibiotic. For its separation from fermentation broth in production, solvent extraction is usually applied because of its low cost and high capacity compared to other bioseparation methods. The multistage mixer-settler is a common extraction equipment in commercial production, but it occupies a large area and causes pollution. In this study, a fully enclosed turbine tower was designed and applied in order to replace the mixer-settler. Its structure parameters (turbine diameter, tray porosity) were optimized on the basis of the extraction effect of lincomycin. The results showed that with 35% tray porosity and 28/26 mm turbine diameter of the tower, the extraction rate was kept above 99.0% steadily under 375 rpm/min rotating speed and 60 °C temperature. The extraction effect is much better than mixer-settler and such turbine tower is expected to be applied in the commercial production of lincomycin.

[Quality evaluation methods for standard decoction of Nelumbinis Folium]

The quality evaluation method for standard decoction of Chinese herbal slices is the basis for the quality evaluation of granules and preparations of classical formula(decoction)of traditional Chinese medicine. This study aimed to establish a method for the determination of quercetin-3-O-glucuronic acid in Nelumbinis Folium(NF)and its standard decoction, so as to provide reference for the quality control of NF and its standard decoction. Fifteen batches of representative NF were collected to prepare standard decoction, and the parameters of dry extract rate, transfer rate of index component, and pH value were calculated. HPLC was used to establish the content determination method for quercetin-3-O-glucuronic acid in NF and its standard decoction. The concentration range of quercetin-3-O-glucuronic acid in the standard decoction of NF was 1.09-3.06 g·L~(-1), while the concentration range of nuciferine was 0.01-0.17 g·L~(-1). The average extraction rate of NF standard decoction was(14.4±2.6)%, the average transfer rate of quercetin-3-O-glucuronic acid was(70.7±18.6)%, and the average transfer rate of nuciferine was(9.6±5.4)%. Compared with Nuciferine, quercetin-3-O-glucuronic acid had a high content and stable transfer rate in standard decoction, and was recommended to be the quality control marker for NF and its standard decoction. This paper establishes a quality evaluation method for NF standard decoction, and can provide reference for the quality control of all preparations derived from NF and its decoction.

Obtaining anthocyanin from jambolan fruit: Kinetics, extraction rate, and prediction of process time for different agitation frequencies

In the literature, in general, the kinetics of bioactive compounds extraction from a solid-liquid system is described by diffusion models and by the Peleg model. In this study, four experiments on the kinetics of anthocyanin extraction from jambolan fruit, at different agitation frequencies of the medium (0, 50, 100, and 150 rpm), are described by various empirical models with up to two fit parameters. According to the statistical indicators, the best model to describe the kinetic processes was Page's, which was also used to determine the extraction rates (all decreasing) and estimate the process times for each agitation frequency. The extraction time for the 150 rpm frequency is approximately six times shorter than that for 0 rpm. Thus, the 150 rpm frequency can be recommended for industrial applications, as the process time is an important variable in the production cost.