Discovery of new quaternized norharmane dimers as potential anti-MRSA agents.

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA)-caused infections greatly threaten public health. The discovery of natural-product-based anti-MRSA agents for treating infectious diseases has become one of the current research focuses. OBJECTIVES: This study aims to identify promising anti-MRSA agents with a clear mechanism based on natural norharmane modified by quaternization or dimerization. METHODS: A total of 32 norharmane analogues were prepared and characterized. Their antibacterial activities and resistance development propensity were tested by the broth double-dilution method. Cell counting kit-8 and hemolysis experiments were used to assess their biosafety. The plasma stability, bactericidal mode, and biofilm disruption effects were examined by colony counting and crystal violet staining assays. Fluorescence microscopy, metabolomic analysis, docking simulation and spectra titration revealed its anti-MRSA mechanisms. The mouse skin infection model was used to investigate the in vivo efficacy. RESULTS: Compound 5a was selected as a potential anti-MRSA agent, which exhibited potent anti-MRSA activity in vitro and in vivo, low cytotoxicity and hemolysis under an effective dose. Moreover, compound 5a showed good stability in 50% plasma, a low tendency of resistance development and capabilities to disrupt bacterial biofilms. The mechanism studies revealed that compound 5a could inhibit the biosynthesis of bacteria cell walls, damage the membrane, disturb energy metabolism and amino acid metabolism pathways, and interfere with protein synthesis and nucleic acid function. CONCLUSIONS: These results suggested that compound 5a is a promising candidate for combating MRSA infections, providing valuable information for further exploiting a new generation of therapeutic antibiotics.

Molecular phylogeny and inflorescence evolution of Prunus (Rosaceae) based on RAD-seq and genome skimming analyses.

Prunus is an economically important genus widely distributed in the temperate Northern Hemisphere. Previous studies on the genus using a variety of loci yielded conflicting phylogenetic hypotheses. Here, we generated nuclear reduced representation sequencing data and plastid genomes for 36 Prunus individuals and two outgroups. Both nuclear and plastome data recovered a well-resolved phylogeny. The species were divided into three main clades corresponding to their inflorescence types, - the racemose group, the solitary-flower group and the corymbose group - with the latter two sister to one another. Prunus was inferred to have diversified initially in the Late Cretaceous around 67.32 million years ago. The diversification of the three major clades began between the Paleocene and Miocene, suggesting that paleoclimatic events were an important driving force for Prunus diversification. Ancestral state reconstructions revealed that the most recent common ancestor of Prunus had racemose inflorescences, and the solitary-flower and corymb inflorescence types were derived by reduction of flower number and suppression of the rachis, respectively. We also tested the hybrid origin hypothesis of the racemose group proposed in previous studies. Prunus has undergone extensive hybridization events, although it is difficult to identify conclusively specific instances of hybridization when using SNP data, especially deep in the phylogeny. Our study provides well-resolved nuclear and plastid phylogenies of Prunus, reveals substantial cytonuclear discord at shallow scales, and sheds new light on inflorescence evolution in this economically important lineage.

The effectiveness of mindfulness-based cognitive therapy combined with medication therapy in preventing recurrence of major depressive disorder in convalescent patients.

Objective: This study aims to investigate the effectiveness of mindfulness-based cognitive therapy (MBCT) combined with medication therapy in preventing the recurrence of major depressive disorder (MDD) in convalescent patients. Methods: A total of 130 patients with convalescent MDD were enrolled in this prospective study. Sixty-five patients were assigned to the experimental group and received medication therapy combined with MBCT, and 65 patients were assigned to the control group and treated with medication alone. The recurrence rate and related hormonal changes were compared between the two groups. Results: After 1 year of MBCT intervention, eight patients experienced recurrence in the experimental group, a recurrence rate of 12.31%, and 19 patients experienced recurrence in the control group, a recurrence rate of 29.23%. The Hamilton Depression Rating Scale (HAM-D) and the World Health Organization Quality of Life Scale (WHOQOL-BREF) scores in both the experimental and the control groups were significantly improved after treatment (P < 0.05). The difference in the HAM-D scores before and after treatment in the experimental group was 16.74 ± 4.54; this was significantly higher than that of the control group (8 ± 3.89, P < 0.0001). The WHOQOL-BREF scores in the experimental group were significantly improved compared with those of the control group (P < 0.0001). The differences in the levels of corticotrophin-releasing hormone (CRH), adrenocorticotropic hormone, and cortisol before and after treatment in the experimental group and the control group were statistically significant (P < 0.05). The difference in CRH before and after treatment in the experimental group was 16.8 ± 7.2, which was higher than that of the control group (2.75 ± 9.27, P < 0.0001). The intervention with MBCT had a significant impact on the recurrence of MDD [ß = 1.206, P = 0.039, 95% (confidence interval) CI = 0.0790-1.229]. The difference in the HAM-D scores also had a significant impact on the recurrence of MDD (ß = 1.121, P = 0.0014, 95% CI = 0.805-0.976). Conclusion: Compared with medication therapy alone, the use of MBCT combined with medication therapy can effectively prevent the recurrence of MDD in convalescent patients.

Changes in the psychological defense mechanism and clinical features of patients with OCD - A four-year follow-up study.

OBJECTIVE: The present study aims to (1) follow up with 4-year changes in the efficacy outcome, defense style questionnaire (DSQ) score, and clinical features of patients with obsessive-compulsive disorder (OCD) and (2) analyze the relationship between different levels of efficacy and changes in the patients' psychological defense mechanisms. METHODS: The following data collection and 4-year follow-up were completed for 153 patients with OCD: (1) the treatment process, efficacy outcome, course of disease, and clinical features of OCD were collected using a self-made general information questionnaire and (2) the control method was used to analyze the changes in clinical symptoms (Yale-Brown obsessive compulsive scale [YBOCS], Hamilton anxiety score [HAMA], and Hamilton depression scale [HAMD]) in patients with OCD. Moreover, the changes in the psychological defense mechanism (measured by DSQ) and the relation between the prognosis and DSQ score were investigated. RESULTS: (1) The HAMA score (8.7 ±â€¯4.8 points), HAMD score (12.0 ±â€¯6.6 points) and YBOCS score (16.4 ±â€¯8.4 points) were significantly lower during the follow-up than at the time of enrollment (p < 0.01). In the two DSQ evaluations, there were no significant differences in the factors, with the exception of a significant decrease in the use of "reaction formation" (t = 2.533, p = 0.015). The changes of mature defense factors in the significant efficacy group significantly increased (p < 0.01). Which was mainly manifested in the significant increase in the score of "sublimation" item, and the difference was extremely significant (t = -3.093, p = 0.006). CONCLUSION: An abnormal psychological defense mechanism plays an important role in OCD, and the use of a mature defense mechanism is significantly related to the treatment efficacy.

Active-Site-Specific Structural Engineering Enabled Ultrahigh Rate Performance of the NaLi3Fe3(PO4)2(P2O7) Cathode for Lithium-Ion Batteries.

Iron-based mixed-polyanionic cathode Na4Fe3(PO4)2(P2O7) (NFPP) has advantages of environmental benignity, easy synthesis, high theoretical capacity, and remarkable stability. From NFPP, a novel Li-replaced material NaLi3Fe3(PO4)2(P2O7) (NLFPP) is synthesized through active Na-site structural engineering by an electrochemical ion exchange approach. The NLFPP cathode can show high reversible capacities of 103.2 and 90.3 mA h g-1 at 0.5 and 5C, respectively. It also displays an impressive discharge capacity of 81.5 mA h g-1 at an ultrahigh rate of 30C. Density functional theory (DFT) calculation demonstrates that the formation energy of NLFPP is the lowest among NLFPP, NFPP, and NaFe3(PO4)2(P2O7), indicating that NLFPP is the easiest to form and the conversion from NFPP to NLFPP is thermodynamically favorable. The Li substitution for Na in the NFPP lattice causes an increase in the unit cell parameter c and decreases in a, b, and V, which are revealed by both DFT calculations and in situ X-ray powder diffraction (XRD) analysis. With hard carbon (HC) as the anode, the NLFPP//HC full cell shows a high reversible capacity of 91.1 mA h g-1 at 2C and retains 82.4% after 200 cycles. The proposed active-site-specific structural tailoring via electrochemical ion exchange will give new insights into the design of high-performance cathodes for lithium-ion batteries.

A study on diffusion tensor imaging in patients with untreated first-episode obsessive-compulsive disorder.

OBJECTIVE: The present study provides an overview of studies investigating white matter (WM) integrity in patients with obsessive-compulsive disorder (OCD) using diffusion tensor imaging (DTI). Furthermore, it studies the correlation of fractional anisotropy (FA) in abnormal cerebral WM areas with the course and clinical signs of the disease. METHODS: The study subjects were divided into two groups, the OCD group (n=38) and the control group (n=40), based on the Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) diagnostic criteria for OCD. Patients with untreated first-episode OCD were assigned to the OCD group, while healthy volunteers were assigned to the control group. The study group was evaluated in accordance with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Self-Rating Depression Scale (SDS) and Self-Rating Anxiety Scale (SAS). Subjects who met the inclusion criteria underwent whole-brain scanning via 3.0 T structural magnetic resonance imaging (sMRI). The WM FA values in different brain areas were compared between the two groups using voxel-based analysis (VBA). Subsequently, the correlations of the patient Y-BOCS score and disorder course with the FA values in significantly improved encephalic areas were analyzed. RESULTS: (I) The FA values of the right precentral gyrus (PreCG.R), left insular lobe, left inferior frontal gyrus and right inferior occipital gyrus (Occipital_Inf_R) WM were significantly lower in the OCD group than in the control group (P<0.05). Elevated FA values were not observed in the OCD group. (II) FA values of PreCG.R, left insular lobe/left inferior frontal gyrus, and Occipital_Inf_R were not found in relation to the total Y-BOCS score (P=0.122; P=0.401; P=0.134), obsessional thoughts score (P=0.299; P=0.760; P=0.062), compulsive activities checklist (P=0.487; P=0.420; P=0.431), and disease course (P=0.604; P=0.380; P=0.182). CONCLUSIONS: Multiple microstructural cerebral WM changes were observed in the frontal lobe, occipital lobe, and insula in patients with untreated first-episode OCD, presenting the correlation of these changes with OCD occurrence.

Comparative Chloroplast Genomics and Phylogenetic Analysis of Zygophyllum (Zygophyllaceae) of China.

The genus Zygophyllum comprises over 150 species within the plant family Zygophyllaceae. These species predominantly grow in arid and semiarid areas, and about 20 occur in northwestern China. In this study, we sampled 24 individuals of Zygophyllum representing 15 species and sequenced their complete chloroplast (cp) genomes. For comparison, we also sequenced cp genomes of two species of Peganum from China representing the closely allied family, Nitrariaceae. The 24 cp genomes of Zygophyllum were smaller and ranged in size from 104,221 to 106,286 bp, each containing a large single-copy (LSC) region (79,245-80,439 bp), a small single-copy (SSC) region (16,285-17,146 bp), and a pair of inverted repeat (IR) regions (3,792-4,466 bp). These cp genomes contained 111-112 genes each, including 74-75 protein-coding genes (PCGs), four ribosomal RNA genes, and 33 transfer RNA genes, and all cp genomes showed similar gene order, content, and structure. The cp genomes of Zygophyllum appeared to lose some genes such as ndh genes and rRNA genes, of which four rRNA genes were in the SSC region, not in the IR regions. However, the SC and IR regions had greater similarity within Zygophyllum than between the genus and Peganum. We detected nine highly variable intergenic spacers: matK-trnQ, psaC-rps15, psbZ-trnG, rps7-trnL, rps15-trnN, trnE-trnT, trnL-rpl32, trnQ-psbK, and trnS-trnG. Additionally, we identified 156 simple sequence repeat (cpSSR) markers shared among the genomes of the 24 Zygophyllum samples and seven cpSSRs that were unique to the species of Zygophyllum. These markers may be useful in future studies on genetic diversity and relationships of Zygophyllum and closely related taxa. Using the sequenced cp genomes, we reconstructed a phylogeny that strongly supported the division of Chinese Zygophyllum into herbaceous and shrubby clades. We utilized our phylogenetic results along with prior morphological studies to address several remaining taxonomic questions within Zygophyllum. Specifically, we found that Zygophyllum kaschgaricum is included within Zygophyllum xanthoxylon supporting the present treatment of the former genus Sarcozygium as a subgenus within Zygophyllum. Our results provide a foundation for future research on the genetic resources of Zygophyllum.

On the Species Delimitation of the Maddenia Group of Prunus (Rosaceae): Evidence From Plastome and Nuclear Sequences and Morphology.

The recognition, identification, and differentiation of closely related plant species present significant and notorious challenges to taxonomists. The Maddenia group of Prunus, which comprises four to seven species, is an example of a group in which species delimitation and phylogenetic reconstruction have been difficult, due to the lack of clear morphological distinctions, limited sampling, and low informativeness of molecular evidence. Thus, the precise number of species in the group and the relationships among them remain unclear. Here, we used genome skimming to generate the DNA sequence data for 22 samples, including 17 Maddenia individuals and five outgroups in Amygdaloideae of Rosaceae, from which we assembled the plastome and 446 single-copy nuclear (SCN) genes for each sample. The phylogenetic relationships of the Maddenia group were then reconstructed using both concatenated and coalescent-based methods. We also identified eight highly variable regions and detected simple sequence repeats (SSRs) and repeat sequences in the Maddenia species plastomes. The phylogenetic analysis based on the complete plastomes strongly supported three main subclades in the Maddenia group of Prunus, while five subclades were recognized based on the nuclear tree. The phylogenetic network analysis detected six hybridization events. Integrating the nuclear and morphological evidence, we proposed to recognize five species within the Maddenia group, i.e., Prunus fujianensis, P. himalayana, P. gongshanensis, P. hypoleuca, and P. hypoxantha. Within this group, the first three species are well-supported, while the gene flow occurring throughout the Maddenia group seems to be especially frequent between P. hypoleuca and P. hypoxantha, eroding the barrier between them. The phylogenetic trees based on eight concatenated hypervariable regions had a similar topology with the complete plastomes, showing their potential as molecular markers and effective barcodes for further phylogeographic studies on Maddenia.

Polysaccharides from Polyporus umbellatus: A review on their extraction, modification, structure, and bioactivities.

Polyporus umbellatus (Pers.) Fries, a well-known medicinal fungus, has been reported to exhibit important functions of diuresis and dampness infiltration in traditional Chinese Medicine. Accumulating evidences have demonstrated that the P. umbellatus polysaccharides (PUPs) are the main and representative pharmacologically active ingredients and display multiple bioactivities both in vivo and in vitro methods, such as those of antioxidant, immunomodulatory, antitumor, anti-proliferative and hepatoprotective. Besides, many PUPs have been isolated from the different sources of P. umbellatus, including sclerotia, fruiting body, mycelia and fermentation liquid of this fungus. The purpose of the present review is to comprehensively and systematically reorganize the available information related to the extraction, purification, modification, structure characterization and to discuss diverse biological activities of PUPs to support their potential application value in pharmaceuticals field, functional foods and cosmetics areas. In addition, new invaluable insights on the future research with PUPs have also been proposed in the important areas of structural characterization and pharmacological activities.

Hollow-Sphere-Structured Na4Fe3(PO4)2(P2O7)/C as a Cathode Material for Sodium-Ion Batteries.

The mixed polyanionic material Na4Fe3(PO4)2(P2O7) combines the advantages of NaFePO4 and Na2FeP2O7 in capacity, stability, and cost. Herein, we synthesized carbon-coated hollow-sphere-structured Na4Fe3(PO4)2(P2O7) powders by a scalable spray drying route. The optimal sample can deliver a high discharge capacity of 107.7 mA h g-1 at 0.2C. It also delivers a capacity of 88 mA h g-1 at 10C and a capacity of retention of 92% after 1500 cycles. Ex situ X-ray diffraction analysis indicates a slight volume change (less than 3%) in the Na4Fe3(PO4)2(P2O7) lattice cell. Therefore, such a spraying-derived carbon-coated Na4Fe3(PO4)2(P2O7) powder is a very attractive cathode electrode for sodium-ion batteries.

Self-Template Synthesis of NaCrO2 Submicrospheres for Stable Sodium Storage.

Sodium-ion batteries (SIBs) are the appropriate alternatives to lithium-ion batteries (LIBs) for the large-scale energy storage applications because of the abundant resources and wide distribution of sodium on earth. O3-NaCrO2 is a promising cathode material for SIBs due to its stable structure and low-cost raw materials. In this paper, we design and synthesize a powder consisting of submicrometer-sized O3-NaCrO2 spheres (s-NaCrO2) self-assembled with nanoflakes, which exhibits faster ion migration ability and strong structure robustness. The galvanostatic intermittent titration technique test reveals the higher apparent Na+ diffusion coefficient of s-NaCrO2 when compared with a normal NaCrO2 powder with an irregular particle morphology. The s-NaCrO2 shows impressive electrochemical properties with a capacity of 90 mAh g-1 at 50 C. In addition, outstanding cycling stability is shown when tested at 20 C, where a capacity of 90 mAh g-1 is maintained with a retention of 87% after 1500 cycles. Also, s-NaCrO2 is advantageous at high (50 °C) and low (-10 °C) temperatures. The full cells assembled employing Sb/C as the anode exhibit good rate capability with 85 mAh g-1 obtained at 50 C.

Complete plastome sequence of Prunus hypoxantha (Rosaceae), a species endemic in west of China.

The Chinese endemic species Prunus hypoxantha is of great importance biogeographically, and is distributed in the edge of the Qinghai-Tibetan Plateau. Here, the complete chloroplast genome sequence of P. hypoxantha was assembled based on the Illumina reads. The complete plastome is 158,740 bp in length, with a large single-copy (87,206 bp) region, a small single-copy (18,884 bp) region, and two inverted repeat (26,325 bp) regions. The plastome contains 134 genes. Complete chloroplast genome sequence of P. hypoxantha will provide irreplaceable information in rebuilding the evolutionary history of the Maddenia clade.

Chloroplast genomes elucidate diversity, phylogeny, and taxonomy of Pulsatilla (Ranunculaceae).

Pulsatilla (Ranunculaceae) consists of about 40 species, and many of them have horticultural and/or medicinal value. However, it is difficult to recognize and identify wild Pulsatilla species. Universal molecular markers have been used to identify these species, but insufficient phylogenetic signal was available. Here, we compared the complete chloroplast genomes of seven Pulsatilla species. The chloroplast genomes of Pulsatilla were very similar and their length ranges from 161,501 to 162,669 bp. Eight highly variable regions and potential sources of molecular markers such as simple sequence repeats, large repeat sequences, and single nucleotide polymorphisms were identified, which are valuable for studies of infra- and inter-specific genetic diversity. The SNP number differentiating any two Pulsatilla chloroplast genomes ranged from 112 to 1214, and provided sufficient data for species delimitation. Phylogenetic trees based on different data sets were consistent with one another, with the IR, SSC regions and the barcode combination rbcL + matK + trnH-psbA produced slightly different results. Phylogenetic relationships within Pulsatilla were certainly resolved using the complete cp genome sequences. Overall, this study provides plentiful chloroplast genomic resources, which will be helpful to identify members of this taxonomically challenging group in further investigation.

Efficient Identification of Pulsatilla (Ranunculaceae) Using DNA Barcodes and Micro-Morphological Characters.

Pulsatilla (Ranunculaceae) comprises about 40 species, many of which have horticultural and/or medicinal importance. However, the recognition and identification of wild Pulsatilla species is difficult due to the presence of complex morphological characters. DNA barcoding is a powerful molecular tool capable of rapidly and accurately distinguishing between species. Here, we assessed the effectiveness of four commonly used DNA barcoding loci-rbcL (R), trnH-psbA ( T ), matK (M), and ITS (I)-to identify species of Pulsatilla from a comprehensive sampling group. Among the four barcoding single loci, the nuclear ITS marker showed the highest interspecific distances and the highest rate of correct identification. Among the eleven combinations, the chloroplast multi-locus R+T and R+M+T combinations were found to have the best species discrimination rate, followed by R+M. Overall, we propose that the R+M+T combination and the ITS marker on its own are, respectively, the best multi- and single-locus barcodes for discriminating among species of Pulsatilla. The phylogenetic analysis was able to distinguish species of Pulsatilla to the subgenus level, but the analysis also showed relatively low species resolution. This may be caused by incomplete lineage sorting and/or hybridization events in the evolutionary history of the genus, or by the resolution limit of the candidate barcodes. We also investigated the leaf epidermis of eight representative species using scanning electronic microscopy. The resulting micro-morphological characters were valuable for identification of related species. Using additional genome fragments, or even whole chloroplast genomes combined with micro-morphological data may permit even higher resolution of species in Pulsatilla.

Synthesis and In Vitro Antibacterial Activity of Quaternized 10-Methoxycanthin-6-one Derivatives.

BACKGROUND: Based on our previous work, we found that 10-methoxycanthin-6-one displayed potential antibacterial activity and quaternization was an available method for increasing the antibacterial activity. Here, we explored the antibacterial activity of quaternized 10-methoxy canthin-6-one derivatives. METHODS AND RESULTS: Twenty-two new 3-N-benzylated 10-methoxy canthin-6-ones were designed and synthesized through quaternization reaction. The in vitro antibacterial activity against three bacteria was evaluated by the double dilution method. Moreover, the structure-activity relationships (SARs) were carefully summarized in order to guide the development of antibacterial canthin-6-one agents. Two highly active compounds (6p and 6t) displayed 8-fold superiority (MIC = 3.91 µg/mL) against agricultural pathogenic bacteria R. solanacearum and P. syringae compared to agrochemical streptomycin sulfate, and showed potential activity against B. cereus. Moreover, these two compounds exhibited good "drug-like" properties, low cytotoxicity, and no inhibition on seed germination. CONCLUSIONS: This work provides two new effective quaternized canthin-6-one derivatives as candidate bactericide, promoting the development of natural-sourced bactericides and preservatives.

Three exopolysaccharides from the liquid fermentation of Polyporus umbellatus and their bioactivities.

The exopolysaccharides were extracted and separated from the broth of the liquid fermentation of P. umbellatus, and the antioxidant activities and other relative bioactivities were investigated, aiming to find clues for a wider use in the future. Three novel exopolysaccharides of PPS1, PPS2 and PPS3 with molecular weight of 3.7×104-6.9×104Da were obtained. Monosaccharide analysis showed that they were mainly composed of mannose, along with galactose and glucose with different molar ratio, and their structural features were also investigated by FT-IR, NMR and SEM. The antioxidant activity assay in vitro showed these exopolysaccharides exhibited a significant scavenging effect on DPPH· and other free radicals in a dose-dependent manner. Significantly, the stimulate nitric oxide production and phagocytic activity implied that the polysaccharides could enhance the immunity of RAW 264.7 macrophages. Other assays revealed that they have obvious cellular aging delaying activity and the DNA damage protecting activity. In conclusion, these three exopolysaccharides might have potential applications in the fields of pharmaceuticals, cosmetics, and food products.

Activity-guided isolation of phase II enzyme inducers from buckwheat flour methanolic extracts.

BACKGROUND: Buckwheat is an important alternative crop and a raw material for functional food formulation. Phase II detoxification proteins/enzymes provide cytoprotective roles against oxidative stress and inflammation originating from various stressors. We aimed to identify and characterize potential phase II enzyme inducers from methanolic extracts of buckwheat flour, using an activity-guided fractionation based on the induction of quinone reductase (QR) (EC 1.6.5.2) in Hepa 1c1c7 cells. RESULTS: We isolated the QR inducers N-trans-feruloyltyramine (I), syringic acid (II), quercetin (III) and myricetin (IV). The relative QR-inducing ability, as well as the concentration required to double QR specific activity (CD values, in parentheses), decreased in the order: quercetin (3.0 µmol L-1 ) > N-trans-feruloyltyramine (24 µmol L-1 ) > myricetin (58 µmol L-1 ) > syringic acid (5.4 mmol L-1 ). Quercetin and N-trans-feruloyltyramine exhibited the greatest extent of QR induction of an approximately four-fold maximum induction and these compounds also exhibited the greatest values for the ratio of IC50 (i.e. level to reduce viability by 50%): CD values of 11 and > 8.3, respectively, among the four QR inducers isolated. Isobologram analyses for binary combinations of compounds I-IV revealed primarily antagonistic interactions for QR induction. CONCLUSION: These findings add to our understanding of the nutraceutical potential of buckwheat as a chemoprophylactic dietary component. © 2018 Society of Chemical Industry.

Characteristic differences in essential oil composition of six Zanthoxylum bungeanum Maxim. (Rutaceae) cultivars and their biological significance.

Great variations have been found in composition and content of the essential oil of Zanthoxylum bungeanum Maxim. (Rutaceae), resulting from various factors such as harvest time, drying and extraction methods (Huang et al., 2006; Shao et al., 2013), solvent and herbal parts used (Zhang, 1996; Cao and Zhang, 2010; Wang et al., 2011). However, in terms of artificial introduction and cultivation, there is little research on the chemical composition of essential oil extracted from Z. bungeanum Maxim. cultivars, which have been introduced from different origins. In this study, the composition and content of essential oil from six cultivars (I-VI) have been investigated. They were introduced and cultivated for 11 years in the same cultivation conditions. Cultivars were as followings: Qin'an (I) cultivar originally introduced from Qin'an City in Gansu Province; Dahongpao A (II) from She County in Hebei Province; Dahongpao B (III) from Fuping County; Dahongpao C (IV) from Tongchuan City; Meifengjiao (V) from Feng County; and, Shizitou (VI) from Hancheng City, in Shaanxi Province, China. This research is expected to provide a theoretical basis for further introduction, cultivation, and commercial development of Z. bungeanum Maxim.

Synthesis and Evaluation of Ester Derivatives of 10-Hydroxycanthin-6-one as Potential Antimicrobial Agents.

As part of our continuing research on canthin-6-one antimicrobial agents, a new series of ester derivatives of 10-hydroxycanthin-6-one were synthesized using a simple and effective synthetic route. The structure of each compound was characterized by NMR, ESI-MS, FT-IR, UV, and elemental analysis. The antimicrobial activity of these compounds against three phytopathogenic fungi (Alternaria solani, Fusarium graminearum, and Fusarium solani) and four bacteria (Bacillus cereus, Bacillus subtilis, Ralstonia solanacearum, and Pseudomonas syringae) were evaluated using the mycelium linear growth rate method and micro-broth dilution method, respectively. The structure-activity relationship is discussed. Of the tested compounds, 4 and 7s displayed significant antifungal activity against F. graminearum, with inhibition rates of 100% at a concentration of 50 µg/mL. Compounds 5, 7s, and 7t showed the best inhibitory activity against all the tested bacteria, with minimum inhibitory concentrations (MICs) between 3.91 and 31.25 µg/mL. Thus, 7s emerged as a promising lead compound for the development of novel canthine-6-one antimicrobial agents.

Synthesis, in vitro antibacterial activities of a series of 3-N-substituted canthin-6-ones.

An improved synthetic route of canthin-6-one was accomplished. To further enhance the antibacterial potency and improve water solubility, a series of 3-N-alkylated and 3-N-benzylated canthin-6-ones were designed and synthesized, and their in vitro antibacterial activities were evaluated. A clear structure-activity relationship with peak minimal inhibitory concentration (MIC) values of 0.98 (µg·mL(-)(1)) was investigated. Particularly, compounds 6i-r and 6t were found to be the most potent compounds with minimal inhibitory concentration (MIC) values lower than 1.95 (µg·mL(-)(1)) against Staphylococcus aureus.