Fermentation of flaxseed cake increases its nutritional value and utilization in ducklings.

Flaxseed cake (FSC) is a potential alternative feed source in poultry. However, cyanogenetic glycosides limit its widespread use in feed. In this study, we optimized the parameters of fermentation by Aspergillus niger and Candida utilis and compared the growth performance, serum lipid parameters, and organ indexes of Cherry Valley duckling feed with unfermented FSC (UFSC) or fermented FSC (FFSC). A total of 420 one-day-old male Cherry Valley ducklings were randomly assigned into a 1 plus 2 × 3 factorial design including 2 different FSC resources (UFSC and FFSC) at 3 levels (50, 100, or 150 g/kg) for 3 wk. Each treatment group included 6 pens with 10 ducklings per pen. The hydrocyanic acid (HCN) level was reduced under the following conditions: 1:0.8 FSC:water (w:v), inoculum ratio of 1 mL:1 mL, 30°C, and 60 h. FFSC had higher crude protein (CP) and calcium (Ca) levels and lower HCN levels compared with UFSC (P < 0.05). There was no interactive effect between FSC sources and levels on growth performance. Final body weight (FBW), average daily feed intake (ADFI), and average daily gain (ADG) in UFSC groups and ADFI in FFSC groups decreased linearly with increasing FSC levels (P < 0.01). There were no differences in FBW, ADG, or feed:gain ratio (F/G) among FFSC groups, and all 7 FSC groups had no differences in the F/G ratio (P > 0.05). Dietary FSC supplementation decreased triglyceride (TG) (P < 0.01), total cholesterol (TC) (P < 0.01), high-density lipoprotein (HDL) (P = 0.01), and low-density lipoprotein (LDL) (P < 0.01). No interactive effect between FSC levels and sources was observed for serum TG, TC, HDL, or LDL. Ducklings fed FFSC had lower TG (P < 0.01), TC (P = 0.05), and LDL (P < 0.01) levels compared with ducklings fed UFSC. The 150 g/kg FFSC group had the lowest TG, TC, HDL, and LDL levels among all 7 groups. Flaxseed cake supplementation decreased the relative weight of the left breast, but FFSC increased the relative weight of the gizzard compared with UFSC. In conclusion, fermentation could increase the nutritional value and usage of FSC in ducklings.

Strategies for the improvement of salidroside production in cell suspension cultures of Rhodiola sachalinensis.

Strategies of elicitation and precursor feeding were applied to improve salidroside production in cell suspension cultures of Rhodiola sachalinensis. Of the seven elicitors examined, that extracted from Aspergillus niger was the most effective, increasing the salidroside content by five-fold when added on the day of inoculation 40 mg carbohydrate is medium. Three possible precursors for salidroside synthesis, L-phenylalanine, L-tyrosol and L-tyrosine were added to the cultures. A high content of salidroside (1.440%) was attained with an initial L-tyrosol concentration of 0.5 mM in the medium. Combined application of the two strategies resulted in a significantly high salidroside content of 1.734%, corresponding to a salidroside yield of 200 mg/l.

Purification of serum albumin with dye-ligand adsorption chromatography.

Dye molecules were coupled to agarose gel beads to form blue, red and yellow chromatography media for the separation of serum albumin. The adsorption properties of five dye-ligands were compared and the effects of temperature, pH, protein concentration and salt concentration were investigated. Human serum albumin (HSA) was purified from human placental plasma by a single step of dye-ligand chromatography under suitable operating conditions. The product was electrophoretically pure, and the elution recovery was as high as 95%. This new technique is superior to the conventional salting-out process.

Continuous fermentation with yeast (Shizosaccharomyces pombe) floccules for ethanol production.

This paper describes an experimental study of continuous fermentation of saccharified starch solution to produce ethanol with yeast particles of a highly flocculent strain of Schizosaccharomyces pombe, which were treated as immobilized microbial cells. Observations were initially made on yeast floccule characteristics during fermentation. An aeration-type fluidized-bed bioreactor that retained virtually all the yeast particles was built and operated continuously for 3 months. Bioreactor operation was found to be quite favorable for this fermentation system. The yeast concentration exceeded 40 g (dry mass)/liter; delivery of a limited amount of supplementary oxygen enhanced throughput to give levels as high as 20-24 g/liter.hr. The kinetic equations were also determined.