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In order to solve the increasingly serious problems of energy and environment, microalgae are used as a raw material for extracting lipids to produce biodiesel. Prior to the extraction of lipids, microalgae were treated with high-voltage pulsed electric field (PEF) to break the cell membrane. It was found that the lipid extraction yield depends on the electric field strength (E) and the specific energy input (Wsp), and has a certain relationship with the cell disintegration rate of Chlorella. The perforation degree of the Chlorella's cell membrane by PEF treatment is controllable, moderate perforation can be ensured by controlling the power parameters. PEF treatment significantly improved the extraction yield of lipids. Compared with the test samples without PEF treatment, PEF treatment increased the lipid extraction yields by up to 166.67%. However, an excessively high voltage will cause the quality of the extracted biodiesel to decrease.

Atmospheric pressure plasma jet (APPJ) has a significant effect on the inactivation of pathogenic microorganisms such as bacteria, virus and fungus. However, sterilization effect of APPJ is restricted by many factors: forms of the power supply (pulse, AC, DC, etc.), parameters of the voltage (amplitude, frequency), time and distance of processing, and the parameters of working gas. In this paper, the system consisting of the pulse power supply and the plasma generation device which uses coaxial cylinder tube, are developed by our research team independently. The system can generate plasma jets of low temperature under atmospheric pressure, using helium as working gas. In the experiment, Escherichia coli, which is typical and common in our environment, was used as the processing object to analyze the sterilization effect of APPJ under different power supply parameters, gas flow rate and processing time. In this paper the composition of plasma jet was analyzed by testing infrared spectra of it and the structure of bacteria was observed by scanning electron microscope (SEM) to study the principle of sterilization. The experimental results show that the active ingredients in APPJ will directly act on bacteria, making the bacterial structure destroyed, cell components lost completely and finally the bacteria inactivated; or the cell fragmentation will occur under the electric field, leading to the thorough loss of bacterial morphology. With the increase of the voltage amplitude or the gas velocity, the sterilization ratio of Escherichia coli increases continuously. Also lengthening the processing time is an effective measure to enhance the sterilization ratio of APPJ. When the processing time exceeds 1 minute, sterilization ratios under different parameters of power supply and gas flow rate can reach 90% or more. The sterilization effect of plasma jet can be obviously seen. Compared to traditional methods such as thermal, chemical and radiate sterilization, APPJ sterilization is more effective, cleaner and free from contamination.

Accumulating evidences have shown that apoptosis plays an important role in mediating the therapeutic effects and toxicity of arsenic. Fas and Bax genes are critical regulatory genes for apoptosis. In this study, we investigated the association between levels of Fas and Bax expression and the three arsenic species (inorganic arsenic (iAs), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)) in vivo and vitro. Three arsenic species in urine were measured and levels of Fas and Bax expression were examined by the quantitative real-time PCR (qPCR) for all subjects. We found that Fas and Bax mRNA expression in the exposed group were significantly higher than that in the control group. The levels of gene expression were positively correlated with the concentrations of urinary iAs, MMA and DMA in all subjects. Sodium arsenite induced Fas and Bax mRNA expression, then MMA and DMA did not induce mRNA expression in MDA-MB-231 and XWLC-05 cells. The findings of the present study indicated that iAs, MMA, and DMA had different effects on expression of Bax and Fas gene.

Pulsed electric field is a novel non-thermal process technology. It could be applied in the extraction of functional components from plant for its irreversible disintegration on plant cell membrane. PEF treatment caused an irreversible disintegration on the cellular membrane of raspberry cell and the extraction yield of anthocyanins from raspberry was linearly correlated to the treatment pulses of PEF. During the extraction, Cyanidin-3-glucoside, the major anthocyanins in raspberry was found to be significantly degraded by PEF. The degradation effects of Cyanidin-3-glucoside decreased with the increase of the electric field or treatment time. In the spectra curves of Cyanidin-3-glucoside treated by PEF, the intensity of the peak at 333 nm increased as electric field and treatment time increased, while the intensity of the peak at 519 nm and the shoulder at 430 nm decreased, indicating Cyanidin-3-glucoside was degraded into chalcone.