Extraction and Separation of Natural Products from Microalgae and Other Natural Sources Using Liquefied Dimethyl Ether, a Green Solvent: A Review.

Microalgae are a sustainable source for the production of biofuels and bioactive compounds. This review discusses significant research on innovative extraction techniques using dimethyl ether (DME) as a green subcritical fluid. DME, which is characterized by its low boiling point and safety as an organic solvent, exhibits remarkable properties that enable high extraction rates of various active compounds, including lipids and bioactive compounds, from high-water-content microalgae without the need for drying. In this review, the superiority of liquefied DME extraction technology for microalgae over conventional methods is discussed in detail. In addition, we elucidate the extraction mechanism of this technology and address its safety for human health and the environment. This review also covers aspects related to extraction equipment, various applications of different extraction processes, and the estimation and trend analysis of the Hansen solubility parameters. In addition, we anticipate a promising trajectory for the expansion of this technology for the extraction of various resources.

Screening, identification, and low-energy ion modified breeding of a yeast strain producing high level of 3-hydroxypropionic acid.

3-Hydroxypropionic acid (3HP) is an important platform chemical with a wide range of applications. The biological preparation of this compound is safe and low cost. In this study, orchard soil and human waste were used as raw materials to screen microbial strains that could produce 3HP in selective medium containing varying amounts of propionic acid. A yeast strain that can use propionic acid as substrate and produce 48.96 g/L 3HP was screened. Morphological observation, physiological and biochemical identification, and 26s rDNA sequencing identified the IS451 strain as Debaryomyces hansenii. The low-energy ion N+ , with the energy of 10 keV and a dose of 70 × 2.6 × 1013  ions/cm2 , was implanted into the IS451 strain. The mutant strain WT39, whose 3HP titer reached 62.42 g/L, was obtained. The strain exhibited genetic stability and tolerance to high concentrations of propionic acid and was considered to have broad application prospects.

Robust, Self-Healing, and Multistimuli-Responsive Supergelator for the Visual Recognition and Separation of Short-Chain Cycloalkanes and Alkanes.

In this study, we show that a novel kind of cholesterol-based gelator NPS containing pyridyl and naphthalimide units can visually discriminate cyclohexane/cyclopentane from hexane/pentane on the basis of distinct optical differences in the gel platform, which is not observed in solution. The effect of congeneric solvents on the gel properties, such as morphology, rheology, and stimuli-responsive properties, is also studied. Intriguingly, NPS can form self-supporting, self-healing, fluorescent, and highly visible transmittance gels in cyclohexane that can selectively and visually respond to picric acid. It is deduced that NPS adopted H-type aggregation mode in cyclohexane, and the gel exhibits a strong green emission, whereas, in hexane, J-type aggregates of NPS molecules are observed with yellow emission. Correlations between the gelation properties and Hansen solubility parameters indicate that the dispersion interactions are the main factor for the selective gelation of NPS toward short-chain alkanes. A comparison of Hansen solvent parameters indicated that a similar energetic weight of the hydrogen-bonding units is the major contribution for the strong and specific interaction between NPS and cyclohexane. Furthermore, we demonstrated that the NPS xerogel can selectively solidify cyclohexane in the single-phase liquid of solvent mixtures, exhibiting fast gelation, high separation efficiency (>92%), and easy recycling of gelator and liquids. To the best of our knowledge, herein, we report the first paradigm that molecular gel formation is developed to visually discriminate and separate organic analogues of solvents with similar polarity.

Evaluating the Reliability and Reproducibility of the AO and Lauge-Hansen Classification Systems for Ankle Injuries.

Ankle injuries are responsible for more than 5 million emergency department visits each year. The AO and Lauge-Hansen classification systems are widely used in the clinical diagnosis of ankle injuries. This study aimed to analyze the intraobserver reliability and interobserver reproducibility of the AO and Lauge-Hansen classification systems. In addition, the authors explored the differences among physicians' classification responses and evaluated the clinical value for diagnosis. Fifty-six patients with an ankle injury with complete clinical and radiologic data were enrolled. The definition of injury type, the index score typing methods, and the specific study criteria were explained in detail. Five observers, who were orthopedic surgeons, determined the classifications according to both the AO and Lauge-Hansen systems. The classification was repeated 1 month later. Cronbach's alpha and Cohen's kappa test were used to determine interobserver reliability and intraobserver reproducibility. The physicians conducted 560 classifications (56 cases × 5 physicians × 2 times per patient). Average inter- and intraobserver kappa values for the AO system were 0.708 and 0.608, respectively. Average inter- and intraobserver kappa values for the Lauge-Hansen system were 0.402 and 0.398, respectively. Cronbach's alpha coefficient was 96.7% for the AO system and 76.0% for the Lauge-Hansen system. The Lauge-Hansen classification system is a comprehensive yet cumbersome system. Comparatively, the AO classification system is easier to understand. This study shows that the AO classification system has more reliability and reproducibility, and thus has more value in clinical practice, than the Lauge-Hansen classification system.

Gene expression profiling and pathway analysis of hepatotoxicity induced by triptolide in Wistar rats.

Triptolide (TP), a major component of TWHF, is widely used to treat rheumatoid arthritis, systemic lupus erythematosus, nephritis and leprosy. However, its clinical use is limited by hepatotoxicity. To further elucidate the underlying mechanism of its hepatotoxic effects, hepatic gene expression profiles were analyzed. TP (1000 and 300 µg/kg) was orally administered to Wistar rats for 14 days. Current study indicated that female rats were more sensitive to TP-induced hepatotoxicity than males. Genome-wide microarray analyses identified 3329 differentially expressed genes in liver of female rats. Analyses of these genes identified over-represented functions associated with insulin signaling pathway, glucose metabolism, cell cycle, oxidative stress and apoptosis, which were consistent with the results of significant increase of Caspase-3 activity and reduction of serum glucose, GSH/GSSG ratio, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase activities, liver glycogen. In addition, it was observed for the first time that glucocorticoids and IGF1 might get involved in TP-induced hepatotoxicity. These data suggest that TP treatment could alter the hepatic redox status, reduce serum glucose and induce hepatocyte apoptosis, consistent with the differential expression of genes involved in insulin signaling pathway, glucose metabolism pathway and cell stress pathway, all of which might contribute to the overall TP-induced hepatotoxicity.