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Silkworm pupae are a major by-product of the silkworm mulberry industry, and the high content of tri-alpha-linolenin (glyceryl tri-alpha-linolenate, LnLnLn) in silkworm pupae oil makes it an excellent essential fatty acid supplement. However, the complex triglyceride composition of silkworm pupae oil limits its absorption and utilization by the human body. In this study, a sequential simulated moving bed (SSMB) approach for continuous separation was presented to recover the high-value tri-alpha-linolenin monomer from silkworm pupae oil. C18 particles were used as the stationary phase. Acetonitrile and isopropanol were used as the elution mobile phases. Under optimal SSMB conditions, the purity and yield of the extracted products were 95.15±2.06% and 2.14±0.06 mg/mL, respectively. In comparison to the conventional extraction approach, the yield of tri-alpha-linolenin separated by SSMB was 26.7 times greater, the dose of eluent was lowered by 2 times, and the eluent could be recycled. To validate the experimental parameters, a mass transfer diffusion model was used. The molecular diffusion coefficient of tri-alpha-linolenin was 2.61×10−6 cm2/s, the axial diffusion coefficient was 2.61×10−6+7.56×10−3μ, and the mass transfer diffusion coefficient was 0.87 s−1. The correlation coefficient between the model and the actual measured values was 0.9688. Consequently, the separation of tri-alpha-linolenin monomer in silkworm pupae oil by sequential simulated moving bed chromatography column can be reasonably described and predicted by this model. In conclusion, a novel approach to the commercialization of insect oils was developed by the extraction and purification of tri-alpha-linolenin from silkworm pupae oil using the SSMB approach. [ABSTRACT FROM AUTHOR]

Silkworm pupae are a typical byproduct with high protein content from silk-reeling industry. The aim of this study was to evaluate the performance of defatted silkworm pupae hydrolysate as an alternative nitrogen source to produce polysaccharides and flavonoids using the fungus Phellinus baumii. The results indicated that the defatted silkworm pupa was treated with dispase, and the freeze-dried hydrolysate had a yield of 37% and a nitrogen content of 3.18%. In the fermentation process, the content of the hydrolysates was 32 g/L. Moreover, the consuming reducing sugar accounted for 75.61% of the total reducing sugar and the nitrogen consumption accounted for 35.19% of the total nitrogen content. The maximum biomass produced by the hydrolysate treatment group was 0.6 g/L, and the extracellular flavonoid concentration was 0.4 g/L; the produced extracellular polysaccharide concentration was 7.71 g/L, which was 1.4–5.9 times higher than that of other nitrogen source treatment groups. Therefore, the defatted silkworm pupae hydrolysate is an effective alternative nitrogen source which has great economic value. As a nitrogen source reagent, it enhanced the fermentation ability of P. baumii and increased the yield of extracellular polysaccharides and flavonoids. [ABSTRACT FROM AUTHOR]

Ralstonia solanacearum is a common plant bacterium, and the improper use of chemicals to control this bacterium is harmful to the environment. Many undeveloped aromatic plants and green plant waste can be used for the preparation of essential oils (EOs). EOs have various biological activities, such as bacteriostatic, insecticidal and anti-oxidation, and are currently in the exploration stage for the control of R. solanacearum. In the present study, the inhibitory activity of ten EOs against R. solanacearum was determined by an antibacterial test. To prolong the duration of antibacterial activity, microcapsules of EOs were prepared by the complex coacervation method, and the optimal preparation conditions were obtained by central composite design method. The results showed that cinnamon EOs had the strongest antibacterial activity. For GIM1.71, GIM1.74, GIM1.76, GMI1000 and RS-5, the EC50 values of cinnamon EOs were 0.055 mg/mL, 0.071 mg/mL, 0.03 mg/mL, 0.067 mg/mL and 0.063 mg/mL, respectively. The preparation condition of cinnamon EOs microcapsules was as follows: the core-wall ratio was 4.35:1, the ratio of chitosan and sodium alginate was 0.15:1, and the calcium chloride concentration was 0.95 wt%. The encapsulation efficiency was 87.32%, and the average particle size of microcapsule was 870.4 μm. The release rate of microcapsule was 44.53% at 100 °C for 6 h and the release of the core materials in microcapsules was in line with Korsmeyer–Peppas release kinetics. Microcapsules placed at room temperature for 7 days still had significant antibacterial activity against five species of R. solanacearum. Due to its good stability and antibacterial activity, cinnamon EOs microcapsules will have great market application prospects as antibacterial agents. [ABSTRACT FROM AUTHOR]

Microfluidics has great potential as an efficient tool for a large range of applications in industry. The ability of such devices to deal with an extremely small amount of fluid has additional benefits, including superlatively fast and efficient mass and heat transfer. These characteristics of microfluidics have attracted an enormous amount of interest in their use as a novel tool for lipid production and modification. In addition, lipid resources have a close relationship with energy resources, and lipids are an alternative renewable energy source. Here, recent advances in the application of microfluidics for lipid production and modification, especially in the discovery, culturing, harvesting, separating, and monitoring of lipid-producing microorganisms, will be reviewed. Other applications of microfluidics, such as the modification of lipids from microorganisms, will also be discussed. The novel microfluidic tools in this review will be useful in applications to improve lipid production and modification in the future. [ABSTRACT FROM AUTHOR]