A method has been established by which to determine aldoses and ketoses in plant material simultaneously. Monosaccharides were extracted by sonication with 80% ethanol and sugar oximes formed by treatment of the resultant extract with hydroxylamine and pyridine at 90 degrees C. After reaction, one aliquot of the product was derivatised with acetic anhydride at 90 degrees C, whilst a second aliquot was silylated with HMDS and TMCS at 80 degrees C. Both reaction mixtures were analysed by GC-MS in the SIM mode. Quantivation was linear within the range 1-4 microg/mL and the detection limit for monosaccharides was 5-25 ng/mL. The absolute recoveries were between 73.0 and 90.2% and the RSDs were 3.1-10.0%. This method was applied to analyse the free monosaccharides in Lyceum barbarum L.; eight monosaccharides were present in amounts between 0.26 and 368.65 microg/mg.

A qualitative method was developed for the identification of GSLs in microalgae. Two types of novel GSLs were identified from three strains of Skeletonema, which might have important biological functions. It could also provide a reliable tool for chemotaxonomy of microalgae.

Purpose In situ chemical oxidation using activated persulfate is increasingly applied for source destruction of hydrophobic organic contaminants (HOCs), e.g., PAHs, the target group contaminants of this study. However, the low aqueous solubility and strong sequestration of HOCs by soil aggregates are major hurdles for the oxidation of HOCs in the subsurface. This study aimed to investigate the potential of using microwave-activated persulfate to tackle the above issues and accelerate the remediation of HOC-contaminated sites. Materials and methods Soil sorbed with high levels of phenanthrene, a model compound for PAHs, was used in the study. The effects of microwave, reaction temperature, reaction time, oxidant dosage, and soil to water ratio on the destruction of phenanthrene, persulfate consumption, and slurry pH were studied. Furthermore, the mechanisms of the microwaveactivated process were discussed by comparing the degradation results using microwave-activated persulfate with those using conventional heat-activated persulfate, and potential microwave-specific effects were explored.Results and discussion This study shows that microwaveactivated persulfate is highly effective toward the destruction of high levels of soil-sorbed phenanthrene. The results indicate that higher slurry temperature is critical to initiate a positive feedback loop that induces rapid and efficient destruction of phenanthrene. Furthermore, potential mechanisms of the positive feedback loop were discussed. Though persulfate is mainly activated by the thermal effect of microwave, nonthermal microwave-specific effects were preliminary observed, which induce additional activation of persulfate and further enhance the destruction efficiency of phenanthrene. In addition, how to integrate an in situ microwave soil heating system with the traditional persulfate remediation process for subsurface engineering was discussed to provide guidance for potential applications in field scales. Conclusions Overall, the feasibility of using microwave heating to accelerate persulfate remediation of subsurface organic contaminations was established.

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