Development of the Colorimetric and/or Fluorescent Probes for Detecting Fluoride ions in Aqueous Solution.

Fluoride ion is a strong Lewis base and one of the essential trace elements in human body. It plays a very important role in human health and ecological balance. The deficiency or excessive intake of fluoride ions will cause serious health problems, so the development of a sensitive and accurate detection method for fluoride ions is very important. The colorimetric and/or fluorescence sensing method has been a long standing attractive technique with high sensitivity and fast response. To date, most reported probes for fluoride ion are applicable only in organic solvents or organic-containing aqueous solutions. However, the probes for fluoride ion used in aqueous solution are more practically needed in view of environment protection and human health. In this paper, the materials and designing ideas of the colorimetric and/or fluorescent probes for fluoride ion based on different detection mechanisms in recent years were reviewed. Two main categories including formation of hydrogen bonds and formation of coordination covalent bonds were discussed. The latter one is further subdivided into three types, formation of B-F bond, formation of Si-F bond and formation of Mn+-F bond.

Prolactin and glucocorticoid receptors in the prefrontal cortex are associated with anxiety-like behavior in prenatally stressed adolescent offspring rats.

Prenatal stress (PS) causes anxiety in mothers and their offspring and chewing is a commonly observed behavior during maternal stress. Prolactin (PRL) is an anti-anxiety factor that suppresses the hypothalamic-pituitary-adrenal axis. Here, we studied the roles of PRL, corticosterone (CORT), and their receptors in PS-induced anxiety-like behavior in dams and their offspring. We further investigated whether chewing during maternal stress could prevent PS-induced harmful consequences. Pregnant rats were randomly divided into PS, PS + chewing, and control groups. Anxiety-like behaviors of dams and their adolescent offspring were assessed using the open field test and elevated plus maze. Serum levels of PRL and CORT were measured by ELISA. Expression of mRNA and protein of PRLR and glucocorticoid receptor (GR) in the prefrontal cortex (PFC) were evaluated by qRT-PCR and western blotting, respectively. Compared to the control rats, dams and their female offspring, but not male offspring, in the PS group showed increased anxiety-like behaviors. The PS-affected rats had a lower serum PRL level and increased PRLR expression in the PFC. In contrast, these rats had a higher serum CORT level and decreased GR expression in the PFC. Chewing ameliorated anxiety-like behaviors and counteracted stress-induced changes in serum PRL and CORT, as well as the expression of their receptors in the PFC. Conclusion: PS-induced anxiety-like behavior is associated with changes in the serum levels of PRL and CORT and expression of their receptors in the PFC. Moreover, chewing blunts the hormonal and receptor changes and may serve as an effective stress-coping method for preventing PS-induced anxiety-like behavior.

A Novel Detachable, Reusable, and Versatile Acoustic Tweezer Manipulation Platform for Biochemical Analysis and Detection Systems.

Multifunctional, integrated, and reusable operating platforms are highly sought after in biochemical analysis and detection systems. In this study, we demonstrated a novel detachable, reusable acoustic tweezer manipulation platform that is flexible and versatile. The free interchangeability of different detachable microchannel devices on the acoustic tweezer platform was achieved by adding a waveguide layer (glass) and a coupling layer (polydimethylsiloxane (PDMS) polymer film). We designed and demonstrated the detachable multifunctional acoustic tweezer platform with three cell manipulation capabilities. In Demo I, the detachable acoustic tweezer platform is demonstrated to have the capability for parallel processing and enrichment of the sample. In Demo II, the detachable acoustic tweezer platform with capability for precise cell alignment is demonstrated. In Demo III, it was demonstrated that the detachable acoustic tweezer platform has the capability for the separation and purification of cells. Through experiments, our acoustic tweezer platform has good acoustic retention ability, reusability, and stability. More capabilities can be expanded in the future. It provides a simple, economical, and multifunctional reusable operating platform solution for biochemical analysis and detection systems.

Associations between maternal prenatal depression and neonatal behavior and brain function - Evidence from the functional near-infrared spectroscopy.

BACKGROUND: Maternal prenatal depression is a significant public health issue associated with mental disorders of offspring. This study aimed to determine if maternal prenatal depressive symptoms are associated with changes in neonatal behaviors and brain function at the resting state. METHODS: A total of 204 pregnant women were recruited during the third trimester and were evaluated by Edinburgh Postpartum Depression Scale (EPDS). The mother-infant pairs were divided into the depressed group (n = 75) and control group (n = 129) based on the EPDS, using a cut-off value of 10. Cortisol levels in the cord blood and maternal blood collected on admission for delivery were measured. On day three of life, all study newborns were evaluated by the Neonatal Behavior Assessment Scale (NBAS) and 165 infants were evaluated by resting-state functional near-infrared spectroscopy (rs-fNIRS). To minimize the influences of potential bias on the rs-fNIRS results, we used a binary logistic regression model to carry out propensity score matching between the depressed group and the control group. Rs-fNIRS data from 21 pairs of propensity score-matched newborns were used for analysis. The associations between maternal EPDS scores, neonatal NBAS scores, and cortisol levels were analyzed using linear regressions and the mediation analysis models. RESULTS: Compared to the control group, the newborns in the depressed group had lower scores in the social-interaction and autonomic system dimensions of NBAS (P < 0.01). Maternal and umbilical cord plasma cortisol levels in the depressed group were higher (P < 0.01) than in the control group. However, only umbilical cord plasma cortisol played a negative mediating role in the relationship between maternal EPDS and NBAS in the social-interaction and autonomic system (ß med = -0.054 [-0.115,-0.018] and -0.052 [-0.105,-0.019]. Proportional mediation was 13.57 % and 12.33 for social-interaction and autonomic systems, respectively. The newborns in the depressed group showed decreases in the strength of rs-fNIRS functional connections, primarily the connectivity of the left frontal-parietal and temporal-parietal regions. However, infants in the depressed and control groups showed no differences in topological characteristics of the brain network, including standardized clustering coefficient, characteristic path length, small-world property, global efficiency, and local efficiency (P > 0.05). The social-interaction Z-scores had positive correlations with functional connectivity strength of left prefrontal cortex-left parietal lobe (r = 0.57, p < 0.01)，prefrontal cortex-left parietal lobe - left temporal lobe (r = 0.593, p < 0.01) and left parietal lobe - left temporal lobe (r = 0.498, p < 0.01). Autonomic system Z-scores were also significantly positive correlation with prefrontal cortex-left parietal lobe (r = 0.509, p < 0.01)，prefrontal cortex-left parietal lobe - left temporal lobe (r = 0.464, p < 0.01), left parietal lobe - left temporal lobe (r = 0.381, p < 0.05), and right temporal lobe and left temporal lobe (r = 0.310, p < 0.05). CONCLUSION: This study shows that maternal prenatal depression may affect the development of neonatal social-interaction and autonomic system and the strength of neonatal brain functional connectivity. The fetal cortisol may play a role in behavioral development in infants exposed to maternal prenatal depression. Our findings highlight the importance of prenatal screening for maternal depression and early postnatal behavioral evaluation that provide the opportunity for early diagnosis and intervention to improve neurodevelopmental outcomes.

A lncRNA fine-tunes salicylic acid biosynthesis to balance plant immunity and growth.

Constitutive activation of plant immunity is detrimental to plant growth and development. Here, we uncover the role of a long non-coding RNA (lncRNA) in fine-tuning the balance of plant immunity and growth. We find that a lncRNA termed salicylic acid biogenesis controller 1 (SABC1) suppresses immunity and promotes growth in healthy plants. SABC1 recruits the polycomb repressive complex 2 to its neighboring gene NAC3, which encodes a NAC transcription factor, to decrease NAC3 transcription via H3K27me3. NAC3 activates the transcription of isochorismate synthase 1 (ICS1), a key enzyme catalyzing salicylic acid (SA) biosynthesis. SABC1 thus represses SA production and plant immunity via decreasing NAC3 and ICS1 transcriptions. Upon pathogen infection, SABC1 is downregulated to derepress plant resistance to bacteria and viruses. Together, our findings reveal lncRNA SABC1 as a molecular switch in balancing plant defense and growth by modulating SA biosynthesis.

Development and Evaluation of Two Double-Antibody Sandwich ELISAs for Detecting Severe Fever with Thrombocytopenia Syndrome Virus Infection.

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly emerging tick-borne virus with a fatality rate between 12% and 50%. Currently, effective vaccines or antiviral drugs are not available to treat SFTSV infection, and a diagnostic method for its detecting is urgently needed. Monoclonal (MAb) and polyclonal antibodies (PAbs) against SFTSV were prepared by immunizing animals with the SFTSV nucleocapsid protein (NP). We developed 2 double-antibody sandwich enzyme-linked immunosorbent assays (DAS-ELISAs) to detect the SFTSV NP, which was captured using the MAbs and PAbs generated. Both methods were applicable for the diagnosis of SFTSV-infected patients, as confirmed by a quantitative polymerase chain reaction. Furthermore, the sensitivity and specificity of the 2 assays for diagnosing severe fever with thrombocytopenia syndrome were 100% and the antibodies did not react with recombinant Dabieshan NP or recombinant dengue virus NS1 subtype 1 and 2 proteins. In addition, 2 standard curves were established for quantitative detection of the NP: the monoclonal antibody-based ELISA (MAb-based ELISA) had a lower limit of detection than the polyclonal-based ELISA. Therefore, the MAb-based ELISA can be employed for convenient and effective detection of SFTSV.

Genomic characteristics and pathogenicity of a new bat adenoviruses strains that was isolated in at sites along the southeastern coasts of the P. R. of China from 2015 to 2019.

Bats are important reservoirs for many kinds of emerging zoonotic viruses. In order to explore potential pathogens carried by bats and trace the source of adenovirus outbreaks on the southeastern coast of China, we took pharyngeal and anal swabs from a total of 552 bats (Rhinolophus pusillus) collected from various areas of Chinese southeastern coast. Adenoviruses were identified in 36 out of the 552 samples (6.5%) . Complete genome sequences of two adenovirus isolations from Vero E6 cells were obtained, which were further validated as identical strains via next-generation sequencing and were named Bat-Advcxc6. The cell culture inoculated with the two samples exhibited remarkable cytopathic changes. The full genome has 37,315 bp and owns 29 open reading frames. Phylogenetic analyses confirmed that Bat-Advcxc6 represented a novel bat adenovirus species in the genus Mastadenovirus. Transmission electron microgram showed clear virus particles. Bat-Advcxc6 shared similar characteristics of G + C contents with Bat mastadenovirus WIV11 (Bat mastadenovirus C) found in China in 2016, but differed from this serotype due to a <75% similarity with DNA polymerase amino acid sequences in WIV11. As it is a newly found adenovirus strain according to the international classification criteria, further analyses of virus dynamics, epithelial invasion, and immunization assays are required to explore its potential threats of cross-species transmission.

Fault Detection in the MSW Incineration Process Using Stochastic Configuration Networks and Case-Based Reasoning.

Fault detection in the waste incineration process depends on high-temperature image observation and the experience of field maintenance personnel, which is inefficient and can easily cause misjudgment of the fault. In this paper, a fault detection method is proposed by combining stochastic configuration networks (SCNs) and case-based reasoning (CBR). First, a learning pseudo metric method based on SCNs (SCN-LPM) is proposed by training SCN learning models using a training sample set and defined pseudo-metric criteria. Then, the SCN-LPM method is used for the case retrieval stage in CBR to construct the fault detection model based on SCN-CBR, and the structure, algorithmic implementation, and algorithmic steps are given. Finally, the performance is tested using historical data of the MSW incineration process, and the proposed method is compared with typical classification methods, such as a Back Propagation (BP) neural network, a support vector machine, and so on. The results show that this method can effectively improve the accuracy of fault detection and reduce the time complexity of the task and maintain a certain application value.

Effect of deformation of a flat plate specimen under in-plane blasting loading on 2D and 3D digital image correlation measurement.

In combination with high-speed photography, a 3D digital image correlation (DIC) experimental system suitable for an in-plane blasting experiment is established to effectively explore the mechanism of blasting. The dynamic response of the specimen under in-plane blasting loading is analyzed on the basis of the model experiment, and the effect of out-of-plane deformation on the 2D-DIC measurement under a blasting stress wave is studied. First, the out-of-plane displacement and strain evolution law of the specimen under blasting load are studied by using a 3D-DIC system. Second, an analytical model of the effect of out-of-plane curved displacement on 2D-DIC measurement under the blasting load is proposed on the basis of pinhole imaging theory. Finally, the specific error value and error percentage of out-of-plane displacement to the 2D-DIC measurement results are quantitatively analyzed on the basis of the established theoretical method. Results show that the theoretical error of out-of-plane curved displacement to 2D-DIC accounts for 10.8% of the measured vertical strain. In the polycarbonate plate specimen, the effect of out-of-plane displacement caused by the blasting experiment on 2D-DIC measurements cannot be ignored. This novel, to the best of our knowledge, experimental system provides a wealth of experimental data, including in-plane full-field strain evolution and out-of-plane displacement changes.

Novel CD123 polyaptamer hydrogel edited by Cas9/sgRNA for AML-targeted therapy.

CD123 targeting molecules have been widely applied in acute myelocytic leukemia (AML) therapeutics. Although antibodies have been more widely used as targeting molecules, aptamer have unique advantages for CD123 targeting therapy. In this study, we constructed an aptamer hydrogel termed as SSFH which could be precisely cut by Cas9/sgRNA for programmed SS30 release. To construct hydrogel, rolling-circle amplification (RCA) was used to generate hydrogel containing CD123 aptamer SS30 and sgRNA-targeting sequence. After incubation with Cas9/sgRNA, SSFH could lose its gel property and liberated the SS30 aptamer sequence, and released SS30 has been confirmed by gel electrophoresis. In addition, SS30 released from SSFH could inhibit cell proliferation and induce cell apoptosis in vitro. Moreover, SSFH could prolong survival rate and inhibit tumor growth via JAK2/STAT5 signaling pathway in vivo. Additionally, molecular imaging revealed SSFH co-injected with Cas9/sgRNA remained at the injection site longer than free aptamer. Furthermore, once the levels of cytokines were increasing, the complementary sequences of aptamers injection could neutralize SS30 and relieve side effect immediately. This study suggested that CD123 aptamer hydrogel SSFH and Cas9/sgRNA system has strong potential for CD123-positive AML anticancer therapy.

Experimental study on the effect of defect curvature on the impact fracture behavior of structures using the real-virtual caustics method.

Defects have significant influence on the impact fracture behavior of structures. In this paper, the real-virtual caustics method is used to study the impact fracture behavior of structures with elliptical arc defects under impact loading of the drop hammer, and the impact loading process is simultaneously analyzed. The research results show that impact loading of the drop hammer in this experiment is a multi-period dynamic loading process, and the fracture of specimens under impact loading of the drop hammer is an energy-controlled process. The running crack initiates under impact loading and propagates toward the elliptical arc defect. After reaching the end of the elliptical arc defect, the running crack arrests and accumulates energy, and then it initiates again and propagates toward the loading position. The greater the end curvature of the elliptical arc defect, the shorter the time for the running crack to stagnate and accumulate energy at the defect end, and the earlier the time for the running crack to initiate again at the defect end, the smaller the impact loading stress of the drop hammer and the dynamic stress intensity factor of running crack tip when the running crack initiates again at the defect end.

Design and application of a comprehensive experimental system for real imaging-virtual imaging of dynamic caustics.

On the basis of the principle of caustics, a comprehensive experimental system for real imaging-virtual imaging was designed and established and then applied to dynamic fracture mechanics experiments. An explosion load experimental system was used to investigate the interaction between blast stress waves and prefabricated cracks. The virtual image information of the caustic spot of the crack tip under the radial compressive stress of the explosive load was captured and quantified. Combined with the experimental data obtained by the real imaging system, the entire interaction process of the blast stress wave and prefabricated cracks was quantitatively characterized. The impact load test system was used to carry out three-point bending impact testing on a unilateral offset crack specimen. In the experiment, the load applied to the upper boundary and the stress intensity factor of the crack tip were simultaneously obtained. The comprehensive experimental system had a simple light path and could simultaneously obtain two sets of experimental information for the real and virtual images, respectively. Thereby, abundant and reliable data were obtained for experimental research. In summary, the experimental systems were effectively used in the investigation of impact and explosion dynamics.

A Novel pH-Sensitive Multifunctional DNA Nanomedicine: An Enhanced and Harmless GD2 Aptamer-Mediated Strategy for Guiding Neuroblastoma Antitumor Therapy.

BACKGROUND: GD2 is a mainstream biomarker for neuroblastoma (NB)-targeted therapy. Current anti-GD2 therapeutics exhibit several side effects since GD2 is also expressed at low levels on normal cells. Thus, current anti-GD2 therapeutics can be compromised by the coexistence of the target receptor on both cancer cells and normal cells. PROPOSE: Aptamers are promising and invaluable molecular tools. Because of the pH difference between tumor and normal cells, in this study, we constructed a pH-sensitive aptamer-mediated drug delivery system (IGD-Targeted). METHODS: In vivo Systematic Evolution of Ligands by Exponential Enrichment (SELEX) was used to generate a novel GD2 aptamer. Flow cytometry and molecular docking were applied to assess the binding specificities, affinities abilities of the aptamers. Confocal microscope, CCK8 assay, and BrdU assay were utilized to evaluate whether IGD-Targeted could only bind with GD2 at acidic environment. To evaluate whether IGD-Targeted could inhibit GD2-positive tumor and protect normal cells, in vivo living imaging, histomorphological staining, blood test, and RNA-sequencing were observed in animal model. RESULTS: GD2 aptamer termed as DB67 could bind with GD2-positive cells with high specificity, while has minimal cross-reactivities to other negative cells. It has been validated that the i-motif in IGD-Targeted facilitates the binding specificity and affinity of the GD2 aptamer to GD2-positive NB tumor cells but does not interfere with GD2-positive normal cells at the pH of the cellular microenvironment. In addition, IGD-Targeted is capable of delivering Dox to only GD2-positive NB tumor cells and not to normal cells in vivo and in vitro, resulting in precise inhibition of tumor cells and protection of normal cells. CONCLUSION: This study suggests that IGD-Targeted as a promising platform for NB therapy which could show greater tumor inhibition and fewer side effects to normal cells, regardless of the existence of the same receptor on the target and nontarget cells.

Distribution and genetic diversity of adeno-associated viruses in bats from coastal areas of Southeast China.

Bats are associated with several important zoonotic viruses from different families. One example includes adeno-associated viruses (AAVs), that are extensively detected in several animals, especially primates. To understand AAVs distribution and genetic diversity in the coastal areas of Southeast China, a total of 415 intestine samples were mostly collected from two provinces of southeast China, i.e., Zhejiang and Fujian province. Intestine samples from five bat species were collected for AAVs detection. The average prevalence rate for AAV detection among these samples was 18.6% (77 positives out of 415 samples) and ranged from 11.8 to 28.9% between the five bat species. This suggests that AAVs are widely distributed in diverse bat populations in southeast coastal areas of China. Based on the genome sequence of bat adeno-associated virus-CXC1(BtAAV-CXC1) from one AAV-positive sample, the genetic diversity of the detected AAVs were assessed and analyzed. Phylogenetic analysis revealed that BtAAV-CXC1 was comparatively distant to other major AAVs from mammals and non-mammals, with only a 52.9~64.7% nucleotide identity. However, they were phylogenetically closer to Rhinolophus sinicus bat adeno-associated virus (Rs-BtAAV1), with a 74.5% nt similarity. Partial analysis of the rep and cap overlapping open reading frame (ORF) sequences from bat AAV samples revealed 48 partial rep sequences and 23 partial cap sequences from positive samples shared 86.9 to 100% and 72.3 to 98.8% nucleotide identities among themselves, respectively. This suggests that the detected AAVs had a distinctly high genetic diversity. These findings led us to conclude that diverse AAVs may be widely distributed in bat populations from the southeast regions of China.

A novel small RNA contributes to restrain cellular chain length and anti-phagocytic ability in Streptococcus suis 2.

Streptococcus suis serotype 2 (SS2) is an important porcine and human pathogen. Regulatory small non-coding RNAs (sRNAs) play an essential role in diverse physiological processes, although they remain poorly understood in SS2. In this study, we identified eight novel sRNAs through a combination of computational strategies and experimental identification. To explore roles of these novel sRNAs, sRNA34 was preferentially selected to assess phenotypes of the deletion strain in vitro and in vivo. The inactivation of sRNA34 significantly elongated the cellular chain, remarkably increased sensitivity to phagocytosis by RAW264.7, and attenuated virulence in a mouse infection model. Transcriptomic analysis revealed that inactivation of sRNA34 altered expression of multiple genes contributing to cellular chain formation and elongation, indicating a potential mechanism of sRNA34 in maintaining proper bacterial chain length to resist phagocytosis by the host cell. In summary, sRNA34 is a novel sRNA that contributes to cellular chain regulation and the anti-phagocytosis ability of SS2.

Genomic characterization and infectivity of a novel SARS-like coronavirus in Chinese bats.

SARS coronavirus (SARS-CoV), the causative agent of the large SARS outbreak in 2003, originated in bats. Many SARS-like coronaviruses (SL-CoVs) have been detected in bats, particularly those that reside in China, Europe, and Africa. To further understand the evolutionary relationship between SARS-CoV and its reservoirs, 334 bats were collected from Zhoushan city, Zhejiang province, China, between 2015 and 2017. PCR amplification of the conserved coronaviral protein RdRp detected coronaviruses in 26.65% of bats belonging to this region, and this number was influenced by seasonal changes. Full genomic analyses of the two new SL-CoVs from Zhoushan (ZXC21 and ZC45) showed that their genomes were 29,732 nucleotides (nt) and 29,802 nt in length, respectively, with 13 open reading frames (ORFs). These results revealed 81% shared nucleotide identity with human/civet SARS CoVs, which was more distant than that observed previously for bat SL-CoVs in China. Importantly, using pathogenic tests, we found that the virus can reproduce and cause disease in suckling rats, and further studies showed that the virus-like particles can be observed in the brains of suckling rats by electron microscopy. Thus, this study increased our understanding of the genetic diversity of the SL-CoVs carried by bats and also provided a new perspective to study the possibility of cross-species transmission of SL-CoVs using suckling rats as an animal model.

Virome analysis for identification of novel mammalian viruses in bats from Southeast China.

Bats have been shown as important mammal resevoirs to carry a variety of zoonotic pathogens. To analyze pathogenic species in bats from southeast coastal regions of China, we performed metagenomic sequencing technology for high throughput sequencing of six sentinels from southeast coastal area of China. We obtained 5,990,261 high quality reads from intestine and lung tissue of 235 bats, including 2,975,371 assembled sequences. 631,490 reads predicted overlapping sequences for the open reading frame (ORF), which accounts for 2.37% of all the sequences (15,012/631,490). Further, the acquired virus sequences were classified into 25 viral families, including 16 vertebrate viruses, four plant viruses and five insect viruses. All bat samples were screened by specific PCR and phylogenetic analysis. Using these techniques, we discovered many novel bat viruses and some bat viruses closely-related to known human/animal pathogens, including coronavirus, norovirus, adenovirus, bocavirus, astrovirus, and circovirus. In summary, this study extended our understanding of bats as the viral reservoirs. Additionally, it also provides a basis for furher studying the transmission of viruses from bats to humans.

In vitro and in vivo biological activities of anthocyanins from Nitraria tangutorun Bobr. fruits.

Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.

One Step to Separate Five Alkaloids from Hypecoum leptocarpum by High-Speed Counter-Current Chromatography.

High-speed counter-current chromatography (CCC) was firstly and successfully applied for the preparative separation and purification of alkaloids from crude extract of Hypecoum leptocarpum. After the measurement of partition coefficient of five target alkaloids in the two-phase solvent systems, the CCC was performed well with a two-phase solvent system composed of tetrachloromethane-chloroform-methanol-0.1 M HCl at a volume ratio of 1.5 : 2.5 : 3 : 2 (V/V/V/V). The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. From 120 mg crude extract, 5 mg leptopidine, 32 mg oxohydrastinine, 27 mg (-)-N-methylanadine, 7 mg N-feruloyltyramine and 3 mg hypecoleptopine could be successfully separated. The amides alkaloid, N-feruloyltyramine, was firstly separated from H. leptocarpum. High-performance liquid chromatography analysis showed that the purity of each of the five target alkaloids was over 92%. Their chemical structures were confirmed by (1)H-NMR and (13)C-NMR data.

Preparative Separation of N-Feruloyl Serotonin and N-(p-Coumaroyl) Serotonin from Safflower Seed Meal Using High-Speed Counter-Current Chromatography.

High-speed counter-current chromatography (HSCCC) was successfully applied for the preparative separation and purification of N-feruloyl serotonin (NF) and N-(p-coumaroyl) serotonin (NP) from safflower seed meal. After the measurement of partition coefficient of the two target compounds in the two-phase solvent systems, the HSCCC was performed well with a two-phase solvent system composed of CHCl3-methanol-0.1 M HCl at a volume ratio of 1 : 1 : 1, v/v. The upper phase was used as stationary phase and the lower phase was used as mobile phase. Under the optimized condition, 7.5 mg NF and 6.9 mg NP were separated from 40 mg crude sample with the purity of 98.8 and 97.3%, respectively. The structures of the isolated compounds were identified by (1)H NMR and (13)C NMR.