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In this study, eight phenolic compounds were obtained from the over-ground parts of the Aconitum pendulum (A. pendulum) Busch through an efficient high-speed counter-current chromatography （HSCCC）method. First, the column chromatography for macroporous resin was used for the treatment of crude extract of over-ground parts of A. pendulum Busch. And then, 30% ethanol elution fraction was transferred to HSCCC for separation using the classic ethyl acetate, n-butanol and water system with the solvent ratio of 7:3:10. To improve parting efficiency, a mode of repeated injection was developed. Two groups of compounds existing in one HPLC peak were effectively separated by HSCCC. The results revealed that HSCCC could effectively isolate compounds with the same or similar polarity. Preparative HPLC was used to perform further purification, and then eight phenolic compounds were separated from the over-ground parts of the A. pendulum Busch for the first time. The current investigation successfully provides a reference for phytochemical research and, comprehensive development and utilization of A. pendulum Busch in the future. Furthermore, HSCCC efficiently separated compounds with similar polarity and its combination with preparative HPLC could play a great role in the separation of natural materials. [ABSTRACT FROM AUTHOR]

Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate. [ABSTRACT FROM AUTHOR]

When investigating the long-term variation of wave characteristics as associated with storm surges in the Bohai Sea, the Simulating Waves Nearshore (SWAN) model and ADvanced CIRCulation (ADCIRC) model were coupled to simulate 32 storm surges between 1985 and 2014. This simulation was validated by reproducing three actual wave processes, showing that the simulated significant wave height (SWH) and mean wave period agreed well with the actual measurements. In addition, the long-term variations in SWH, patterns in SWH extremes along the Bohai Sea coast, the 100-year return period SWH extreme distribution, and waves conditional probability distribution were calculated and analyzed. We find that the trend of SWH extremes in most of the coastal stations was negative, among which the largest trend was −0.03 m/a in the western part of Liaodong Bay. From the 100-year return period of the SWH distribution calculated in the Gumbel method, we find that the SWH extremes associated with storm surges decreased gradually from the center of the Bohai Sea to the coast. In addition, the joint probability of wave and surge for the entire Bohai Sea in 100-year return period was determined by the Gumbel logistic method. We therefore, assuming a minimum surge of one meter across the entire Bohai Sea, obtained the spatial SWH distribution. The conclusions of this study are significant for offshore and coastal engineering design. [ABSTRACT FROM AUTHOR]

Highlights • Ghrelin(1–7)-NH 2 (i.c.v.) induced antinociception in acute pain in mice. • Ghrelin(1–7)-NH 2 induced antinociception through GHS-R1α and opioid receptors. • Ghrelin(1–7)-NH 2 (i.c.v.) was distributed at the dorsal 3rd ventricle and hippocampus. • mRNA and protein levels of δ -opioid peptide and receptor were increased in the test. Abstract Ghrelin(1–7)-NH 2 is the active N-terminal hepta-peptide of ghrelin as an agonist at the ghrelin receptor GHS-R1α. The biological functions of ghrelin(1–7)-NH 2 have not been well investigated. Therefore in this study, we were interested in exploring the effects and molecular mechanisms of ghrelin(1–7)-NH 2 in pain modulation at the supraspinal level using the tail withdrawal test in mice. Intracerebroventricular (i.c.v.) injection of ghrelin(1–7)-NH 2 (0.002, 0.02, 0.2 and 2 nmol/kg) induced a dose- and time-related antinociceptive effect. This antinociceptive effect was fully antagonized by co-injection with the GHS-R1α antagonist [D-Lys3]-GHRP-6, indicating that this effect induced by ghrelin(1–7)-NH 2 was mediated through the activation of GHS-R1α. Interestingly, naloxone, β-funaltrexamine, naloxonazine, and naltrindole, but not nor-binaltorphimine, could also antagonize the antinociceptive effect markedly, suggesting that OPRM (primary μ 1 subtype) and OPRD were involved in the antinociceptive response induced by ghrelin(1–7)-NH 2. Furthermore, the qRT-PCR and Western blot results indicated that both mRNA and protein levels of PENK and OPRD were up-regulated significantly. Using the fluorescence labeling method, our results showed that ghrelin(1–7)-NH 2 (i.c.v.) was mainly distributed at the dorsal 3rd ventricle and hippocampus where there are regions with high expressions of ghrelin, GHS-R1α and ORs. All these results indicated that ghrelin(1–7)-NH 2 initially activated the GHS-R1α, then activated the OPRM, as well as increased the release of endogenous PENK to activate of OPRD to produce antinociception. These results contributed to understanding the mechanisms of antinociception induced by ghrelin(1–7)-NH 2. Furthermore, ghrelin(1–7)-NH 2 as the active fragment of ghrelin may be a promising peptide for developing new analgesic drugs. [ABSTRACT FROM AUTHOR]

A sensitive and specific immunosensor was developed by immobilizing HRP-labeled antibody against Listeria monocytogenes onto the surface of the novel multiwalled carbon nanotube fibers. Firstly, the influence of immunoelectrode modification methods (chemical and physical method) on detection sensitivity and stability was studied. Next, immunosensor was developed, optimized, and applied for the detection of L. monocytogenes. The morphology was characterized by scanning electron microscopy (SEM), and electrochemical behaviors were by cyclic voltammetry. SEM image, relative response (%), and current data showed chemical modification for immunoelectrode was helpful to capture more target bacteria and obtain more stable current response, resulting in improving the detection sensitivity. The linear relationship between L. monocytogenes concentration and ΔIpc was from 102 to 105 cfu/mL (R2=0.993), and LOD was 1.07×102 cfu/mL. L. monocytogenes in mixed bacteria (1.51 × 103 cfu/mL) of milk sample (S/N > 14) were detected by developed immunosensor, showing good specificity. Good storage stability and reproducibility (RSD < 6.5%) also showed the potential application of immunosensor for the rapid detection of L. monocytogenes. [ABSTRACT FROM AUTHOR]

High-speed counter-current chromatography (HSCCC) was successfully applied to the isolation and purification of four xanthone glycosides fromHalenia elliptica, a plant widely used in traditional Tibetan medicine. The introduction of HSCCC greatly improved the efficiency of compounds preparation fromHalenia elliptica. The following were obtained from 100 mg of crude sample in one-step separation: 2.5 mg of 1-O-primeverosyl-2,3,4,5,7-pentamethoxyxanthone, 7.0 mg of 1-O-primeverosyl-2,3,4,7- tetramethoxyxanthone, 10.0 mg of 1-O-primeverosyl-2,3,5-trimethoxyxanthone (demethyoxyhaleniaside), and 8.5 mg of 1-O-primeverosyl-2,3,4,5-tetramethoxyxanthone. HPLC analysis showed that each target compound had a purity of over 98%, and UV,1H NMR, and13C NMR data confirmed the component chemical structures. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

Gentiopicroside, mangiferin, sweroside, and isoorientin, the bioactive constituents ofSwertia mussotiiFranch, have various pharmacological effects, and are used in particular for treating liver disorders. However, efficient methods for their separation are not currently available. In this study, these bioactive compounds were detected inS. mussotiiextracts using high-performance liquid chromatography coupled with mass spectrometry, and separated using a combination of high-speed counter-current chromatography and Sephadex LH-20 column chromatography. Their structures were determined by using1H and13C nuclear magnetic resonance spectroscopies. The results show that this method is effective for the separation and purification of bioactive compounds fromS. mussotii. [ABSTRACT FROM AUTHOR]

Summary: The oral bioavailability of tangeretin is limited by its low water solubility and high crystallisation. In the present study, tangeretin was entrapped in whey protein concentrate (WPC)‐stabilised emulsions to enhance its bioaccessibility. Hydroxypropyl methylcellulose (HPMC) was added to modify the interface of the emulsion droplets, and Ca2+‐crosslinking was used to induce the gel formation. Spray drying of the emulsions or gels enabled to produce microcapsules. The physicochemical characteristics and in vitro digestion behavior of the microcapsules were investigated. Results indicated that HPMC modification and Ca2+‐crosslinking increased the average particle size, altered the microstructure, ameliorated the quality of the WPC‐based microcapsules and improved the encapsulation efficiency of tangeretin. Furthermore, the in vitro studies showed that HPMC modified and Ca2+‐added microcapsules could control the release of free fatty acid. HPMC greatly increased the bioaccessibility of tangeretin from around 28% to 80%. Overall, these results confirmed that HPMC‐modified WPC microcapsules could be a promising carrier to protect hydrophobic functional ingredients and improve their oral bioavailability. [ABSTRACT FROM AUTHOR]

Meat adulteration, which adversely impacts food safety, economy, and religious beliefs, has come to be considered as a matter of global concern. The lack of a standard method that can be employed to quantitatively detect the pork content in processed meat products has led to demands for an accurate and sensitive method capable of detecting the proportion of pork in processed beef products. In this study, we aimed to develop a real-time PCR-based method to accurately and quantitatively detect pork adulteration in processed beef. We used bovine and porcine species-specific sequences to design primers and probes that specifically amplified bovine and porcine genes. Our real-time PCR method was evaluated via quantitative detection of reference samples and found to be highly accurate. Sensitivity analyses indicated that the limit of detection for beef as well as for pork was as low as five copies, while the limit of quantification for beef and for pork was 0.1%. To compare qualitative and quantitative results, beef samples cross-contaminated with pork were analyzed using both quantitative and standard qualitative methods. No undeclared meat components were found among the 25 processed meat products that were analyzed to evaluate the applicability of the quantitative method. However, the beef content in some processed beef products was very low, even approaching zero. This real-time PCR method may be reliably applied for quantitatively detect pork adulteration in processed beef products. Thus, this method of ours may help promote healthy and sustainable development of meat products. • This study marks the first utilization of TNFRSF10A and PRNP as target genes for detecting meat adulteration. • 2. The method exhibits lower LOD and LOQ compared to other real-time PCR methods utilizing nuclear genes as targets. • The method employs absolute quantification, overcoming the constraints of relative quantification with reference genes. • The quantitative method offers a new approach to address both deliberate adulteration and accidental contamination. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]