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This study presents an efficient strategy based on liquid-liquid extraction, high-speed counter-current chromatography, and preparative HPLC for the rapid enrichment, separation, and purification of four anthraquinones from Rheum tanguticum. A new solvent system composed of petroleum ether/ethyl acetate/water (4:2:1, v/v/v) was developed for the liquid-liquid extraction of the crude extract from R. tanguticum. As a result, emodin, aloe-emodin, physcion, and chrysophanol were greatly enriched in the organic layer. In addition, an efficient method was successfully established to separate and purify the above anthraquinones by high-speed counter-current chromatography and preparative HPLC. This study supplies a new alternative method for the rapid enrichment, separation, and purification of emodin, aloe-emodin, physcione, and chrysophanol.
In this paper, an efficient method was successfully established by the combination of macroporous resin (MR) and high-speed counter-current chromatography (HSCCC) for rapid enrichment and separation of aloe-emodin 8-O-β-D-glucoside, emodin 1-O-β-D-glucoside, emodin 8-O-β-D-glucoside and piceatannol 4'-O-β-D-(6″-O-gallate)-glucoside. Six kinds of macroporous resins were investigated in the first step and X-5 macroporous resin was selected for the enrichment of the target compounds. The recoveries of the target compounds reached 89.0, 85.9, 82.3 and 84.9% respectively after 40% ethanol elution. In the second step, the target compounds were separated by HSCCC with a two-phase solvent system composed of chloroform/ethyl acetate/methanol/water (8:1:6:5, v/v). The established method will be helpful for further characterization and utilization of Rheum tanguticum. The results demonstrate that MR coupled with HSCCC is a powerful technique for separation of bioactive compounds from natural products.
The ‘Anthropocene’ is now being used as a conceptual frame by different communities and in a variety of contexts to understand the evolving human–environment relationship. However, as we argue in this paper, the notion of an Anthropos, or ‘humanity’, as global, unified ‘geological force’ threatens to mask the diversity and differences in the actual conditions and impacts of humankind, and does not do justice to the diversity of local and regional contexts. For this reason, we interpret in this article the notion of an Anthropocene in a more context-dependent, localized and social understanding. We do this through illustrating examples from four issue domains, selected for their variation in terms of spatial and temporal scale, systems of governance and functional interdependencies: nitrogen cycle distortion (in particular as it relates to food security); ocean acidification; urbanization; and wildfires. Based on this analysis, we systematically address the consequences of the lens of the Anthropocene for the governance of social-ecological systems, focusing on the multi-level, functional and sectoral organization of governance, and possible redefinitions of governance systems and policy domains. We conclude that the notion of the Anthropocene, once seen in light of social inequalities and regional differences, allows for novel analysis of issue-based problems in the context of a global understanding, in both academic and political terms. This makes it a useful concept to help leverage and (re-)focus our efforts in a more innovative and effective way to transition towards sustainability.
We used the Box-Behnken design to optimize polysaccharide extraction from <b>Armillaria luteo-virens</b> (Alb. et Schw. Fr.) Sacc. The independent factors included extraction time (X1), microwave power (X2) and water to raw material ratio (X3). The experimental values were fitted to a second-order polynomial equation using multiple regression analysis and a statistical method. Analysis of Variance results indicated that all factors including X1 - X3 had an impact on <b>Armillaria luteo-virens</b> (Alb. et Schw. Fr.) Sacc. polysaccharide extraction. The optimal conditions for efficient yield of polysaccharide, giving a maximum yield of 8.43%, were: X1 = 30.24 min, X2 = 600.6 W and X3 = 40 mL/g. The model was verified by modifying the optimal conditions (X1 = 30 min, X2 = 601 W and X3 = 40 mL/g) for practical application. A pilot scale test was also carried out under optimal conditions. The obtained yields 8.40 ± 0.12% and 8.34 ± 0.25% were comparable with the optimized condition, which indicated that our model is accurate. Fourier transform infrared spectroscopy characterization revealed that the extracted polysaccharide produced typical absorption peaks. Oxygen radical absorbance capacity results showed the polysaccharides had good potential as an antioxidant. Moreover, the polysaccharide showed relatively strong inhibitory activity on the growth of NCI-H446 cells.<br>• Extraction of ALSP by DEAE technique for the first time. • DEAE method for the extraction of ALSP was built. • ALSP has possessed a good antioxidant activity. • ALSP exhibited antiproliferative activities and may be applied in therapy.
Since it was first proposed in 2000, the concept of the Anthropocene has evolved in breadth and diversely. The concept encapsulates the new and unprecedented planetary-scale changes resulting from societal transformations and has brought to the fore the social drivers of global change. The concept has revealed tensions between generalized interpretations of humanity’s contribution to global change, and interpretations that are historically, politically and culturally situated. It motivates deep ethical questions about the politics and economics of global change, including diverse interpretations of past causes and future possibilities. As such, more than other concepts, the Anthropocene concept has brought front-and-center epistemological divides between and within the natural and social sciences, and the humanities. It has also brought new opportunities for collaboration. Here we explore the potential and challenges of the concept to encourage integrative understandings of global change and sustainability. Based on bibliometric analysis and literature review, we discuss the now wide acceptance of the term, its interpretive flexibility, the emerging narratives as well as the debates the concept has inspired. We argue that without truly collaborative and integrative research, many of the critical exchanges around the concept are likely to perpetuate fragmented research agendas and to reinforce disciplinary boundaries. This means appreciating the strengths and limitations of different knowledge domains, approaches and perspectives, with the concept of the Anthropocene serving as a bridge, which we encourage researchers and others to cross. This calls for institutional arrangements that facilitate collaborative research, training, and action, yet also depends on more robust and sustained funding for such activities. To illustrate, we briefly discuss three overarching global change problems where novel types of collaborative research could make a difference: (1) Emergent properties of socioecological systems; (2) Urbanization and resource nexus; and (3) Systemic risks and tipping points. Creative tensions around the Anthropocene concept can help the research community to move toward new conceptual syntheses and integrative action-oriented approaches that are needed to producing useful knowledge commensurable with the challenges of global change and sustainability.
Anthraquinone glycosides, such as chrysophanol 1-O-β-d-glucoside, chrysophanol 8-O-β-d-glucoside, and physion 8-O-β-d-glucoside, are the accepted important active components of Rheum tanguticum Maxim. ex Balf. due to their pharmacological properties: antifungal, antimicrobial, cytotoxic, and antioxidant activities. However, an effective method for the separation of the above-mentioned anthraquinone glycosides from this herb is not currently available. Especially, greater difficulty existed in the separation of the two isomers chrysophanol 1-O-β-d-glucoside and chrysophanol 8-O-β-d-glucoside. This study demonstrated an efficient strategy based on preparative high-performance liquid chromatography and high-speed countercurrent chromatography for the separation of the above-mentioned anthraquinone glycosides from Rheum tanguticum Maxim.ex Balf.
This study presents an efficient strategy for separation of three phenolic compounds with high molecular weight from the crude extract of Terminalia chebula Retz. by ultrasound-assisted extraction and high-speed counter-current chromatography. The ultrasound-assisted extraction conditions were optimized by response surface methodology and the results showed the target compounds could be well enriched under the optimized extraction conditions. Then the crude extract was directly separated by high-speed counter-current chromatography without any pretreatment using n-hexane/ethyl acetate/methanol/water (1:7:0.5:3, v/v/v/v) as the solvent system. In 180 min, 13 mg of A, 18 mg of B, and 9 mg of C were obtained from 200 mg of crude sample. Their structures were identified as Chebulagic acid (A, 954 Da), Chebulinic acid (B, 956 Da), and Ellagic acid (C) by (1) H NMR spectroscopy.
The effective, energy-saving and green subcritical fluid extraction (SFE) technology was applied to obtain the oil from <i>Lycium ruthenicum</i> seeds (LRSO). The optimal conditions of extraction parameters were found using response surface methodology with Box-Behnken experimental design. The maximum extraction yield of 21.20% was achieved at raw material particle size of 0.60 mm, extraction pressure of 0.63 MPa, temperature of 50 °C and time of 48 min. Other traditional extraction technologies were comparatively used. The physicochemical property of LRSO was analysed and the chemical compositions indicated that they were rich in unsaturated fatty acid, β-carotene, tocopherols and total phenolics. Furthermore, the antioxidant activity of LRSO was evaluated by scavenging activity of three kinds of radicals (DPPH·, ·OH and O₂⁻·) and lipid peroxidation <i>in vitro</i>. And its results showed the oil had the potential to be a novel antioxidant agent for using in the field of food, pharmaceuticals and cosmetics.<br>Lycium ruthenicum seeds oil (LRSO) was obtained by subcritical fluid extraction (SFE), and the process of SFE was optimized using response surface methodology. LRSO was evaluated by determination of physicochemical property, lipophilic compositions and antioxidant activity. The study revealed the possibility of LRSO as a potential source of valuable product for commercial ventures (food, pharmaceuticals or cosmetics).