A dual mechanism with H2S inhibition and membrane damage of morusin from Morus alba Linn. against MDR-MRSA.

It's urgent to discover new antibiotics along with the increasing emergence and dissemination of multidrug resistant (MDR) bacterial pathogens. In the present investigation, morusin exhibited rapid bactericidal activity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) by targeting the phospholipid of bacterial inner membrane, increasing membrane rigidity and disrupting bacterial homeostasis together with the membrane permeability, which caused fundamental metabolic disorders. Furthermore, morusin can also accumulate ROS, suppress H2S production, and aggravate oxidative damage in bacteria. Importantly, morusin also inhibited the spread of wounds and reduced the bacterial burden in the mouse model of skin infection caused by MRSA. It's a chance to meet the challenge of existing antibiotic resistance and avoid the development of bacterial resistance, given the multiple targets of morusin.

Ormosianines A-P, Structurally Diverse Quinolizidine Alkaloids with AChE Inhibitory Effects from Ormosia yunnanensis.

Sixteen new quinolizidine alkaloids (QAs), named ormosianines A-P (1-16), and 18 known congeners (17-34) were isolated from the stems and leaves of Ormosia yunnanensis. The structures were elucidated based on spectroscopic analyses and electron circular dichroism (ECD) calculations. Structurally, ormosianines A (1) and B (2) are the first examples of cytisine and Ormosia-type alkaloids with the cleavage of the piperidine ring. Results of the acetylcholinesterase (AChE) inhibitory assay revealed that the pentacycline Ormosia-type QAs, including 1, 16, 24, and 27-29, are good AChE inhibitors. Ormosianine A (1) exhibited more potent AChE inhibitory activity with an IC50 value of 1.55 µM. Molecular docking revealed that 1 might bind to the protein 1DX4, forming two hydrogen bonds with residues SER-238 and HIS-480.

Targeted quantitative analysis of monoterpenoid indole alkaloids in Alstonia scholaris by ultra-high-performance liquid chromatography coupled with quadrupole time of flight mass spectrometry.

Monoterpene indole alkaloids exhibit structural diversity in herbal resources and have been developed as promising drugs owing to their significant biological activities. Confidential identification and quantification of monoterpene indole alkaloids is the key to quality control of target plants in industrial production but has rarely been reported. In this study, quantitative performance of three data acquisition modes of ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry including full scan, auto-MS2 and target-MS2 , was evaluated and compared for specificity, sensitivity, linearity, precision, accuracy, and matrix effect using five monoterpene indole alkaloids (scholaricine, 19-epi-scholaricine, vallesamine, picrinine, and picralinal). Method validations indicated that target-MS2 mode showed predominant performance for simultaneous annotation and quantification of analytes, and was then applied to determine monoterpene indole alkaloids in Alstonia scholaris (leaves, barks) after extraction procedures optimization using Box-Behnken design of response surface methodology. The variations of A. scholaris monoterpene indole alkaloids in different plant parts, harvest periods, and post-handling processes, were subsequently investigated. The results indicated that target-MS2 mode could improve the quantitative capability of ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry for structure-complex monoterpene indole alkaloids in herbal matrices. Alstonia scholaris, monoterpene indole alkaloids, quadrupole time of flight mass spectrometry, qualitative and quantitative analysis, ultra-high-performance liquid chromatography.

New Lupanes from Alstonia scholaris Reducing Uric Acid Level.

Twelve lupanes including three new compounds named alstoscholarilups A-C (1: -3: ) were isolated from the leaves of Alstonia scholaris. Their structures were elucidated by spectroscopic analysis and ECD calculation. Structurally, compound 1: with a rare A ring-seco skeleton formed lactone and degraded C-3, while 2: with a 28-nor and 3: with a 29-nor-lupane skeleton supported the phytochemical diversity and novelty of the plant. Pharmacologically, compounds 4, 7: , and 10: reduced the serum uric acid (UA) levels of mice significantly.

Phytochemical and Antibacterial Constituents of Edible Globe Amaranth Flower against Pseudomonas aeruginosa.

Globe amaranth flower, the edible inflorescence of Gomphrena globose L., was used to treat dysentery and ulcer as well as other infectious diseases caused by microbes in Southwest China, but its function and bioactive components need experimental support. In this study, phytochemical constituents and antibacterial bioactivity of globe amaranth flower against P. aeruginosa were carried out. As a result, two new (1 and 2) and eleven known (3-11) compounds were isolated, in which compounds 4-7 displayed anti P. aeruginosa bioactivity with the minimum inhibitory concentration (MIC) from 0.008 to 0.256 mg/mL. Furthermore, with aid of the scanning electron microscope (SEM) and a superficial skin infection model in mice, the most potent compound 4 can significantly destroy the structure of bacteria in vitro and restore bacterial infection damage in vivo.

Baoshanmycin and a New Furanone Derivative from a Soil-Derived Actinomycete, Amycolatopsis sp. YNNP 00208.

Actinomycetes have being regarded as a treasure reservoir of various bioactive secondary metabolites and devoted many antibiotics in clinicals. Amycolatopsis sp. YNNP 00208 was isolated from a soil sample collected in Gaoligong Mountain area, Yunnan Province, China. Chemical investigation of its fermentation broth led to a new amide, baoshanmycin (1), and a new furanone derivative, 3-(1,3-dihydroxybutyl)-4-methylfuran-2(H)-one (2), together with eight known compounds, including two amides (3-4), four cyclic dipeptides (5-8), and two deoxyribonucleosides (9-10). Their structures were established on basis of the 1D- and 2D-NMR spectroscopic data, along with the HR-ESI-MS experiments. Baoshanmycin (1) showed moderate antimicrobial activities against Candida albicans, and weak activities against Staphylococcus aureus, multi-drug resistant Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, fluconazole-resistant Candida albicans. Baoshanmycin (1) presented strong antioxidant activity and moderate anti-acetylcholinesterase activity. The other compound 3-(1,3-dihydroxybutyl)-4-methylfuran-2(H)-one (2) and the known compounds (3-10) showed moderate antioxidant activity.

Yi Shen An, a Chinese traditional prescription, ameliorates membranous glomerulonephritis induced by cationic bovine serum albumin in rats.

CONTEXT: Yi Shen An (YSA) is an investigational composite of traditional Chinese medicine (Reference: 2010L000974) for the treatment of renal disease. OBJECTIVE: To investigate the protective effects of YSA against membranous glomerulonephritis (MGN). MATERIALS AND METHODS: Male Sprague-Dawley rats were injected with cationic bovine serum albumin (C-BSA) to create a model of MGN. Then, rats were orally treated with YSA at doses of 0.25, 0.5, 1 and 2 g/kg for 35 successive days; prednisone (5 mg/kg) was used as a positive control. At the end of the experimental period, we performed a series of tests, including 24 h urinary protein, and biochemical, immunological, antioxidative, coagulation indices, and histopathological examination. RESULTS: YSA-1 g/kg significantly lowered urinary protein from 68.37 to 30.74 mg (p < 0.01). Meantime, total protein (TP) and albumin (ALB) recovered from 66.26 and 20.51 g/L to 76.08 and 35.64 g/L (p < 0.01), respectively. YSA removed the deposition of immunoglobulin G (IgG) and complement 3c (C3c), prevented inter-capillary cell hyperplasia on the glomerular basement membrane (GBM), and reduced electron-dense deposits and fusion of podocytes. In addition, serum IgG and superoxide dismutase were significantly elevated. In contrast, malondialdehyde, total cholesterol, triglyceride, circulating immune complex (CIC), and immunoglobulin M decreased in the YSA-treated group. Moreover, the blood coagulation dysfunction was adjusted. DISCUSSION AND CONCLUSIONS: These findings indicate YSA may exert a therapeutic effect against MGN through the inhibition of CIC formation, and the removal of IgG and C3c deposition from the GBM, thus supporting the development of further clinical trials.

C19 Benzylisoquinoline Alkaloid with Unprecedented Architecture from Hypecoum erectum.

Hyperectumine (1), the first C19 benzylisoquinoline alkaloid with a complicated ring system, was isolated from Hypecoum erectum and structurally characterized. Its biosynthetic origin should involve a hybrid pattern of C8 + C8 + C1 + C2, from which a C17 benzylisoquinoline alkaloid might be further attacked by a malonamic acid and undergo decarboxylation and cyclization to produce 1. Compound (-)-1 exhibited moderate anti-inflammatory activity via suppression of LPS-activated inflammatory mediators in RAW 264.7 macrophage cells.

Neothalfine, a potent natural anti-tumor agent against metastatic colorectal cancer and its primary mechanism.

Neothalfine is a natural bisbenzylisoquinoline alkaloid with the abundant resource in medicinal plants and has not been reported its anti-tumor efficacy. In the present study, the anti-tumor efficacy was investigated and it showed broad-spectrum activity against several cancer cell lines, especially metastatic colorectal cancer (HCT116, SW620, T84) with the IC50 values of 7.2, 5.9, 8.2 nM, respectively, roughly equal to well-known anti-tumor agent docetaxel (4.0, 4.7, 2.7 nM) and nearly 1000 folds than CPT-11 (4.4, 5.1, 6.9 µM). Furthermore, neothalfine inhibited colorectal cell proliferation by resulting in cell cycle arrest at the G2/M phase and induced apoptosis through the dysfunction of mitochondria to trigger intrinsic apoptotic pathway by untargeted metabolomic method, mitochondrial membrane potential, and caspase-3/7 activity assay. Moreover, neothalfine damaged colorectal cancer clonal spheres expansion significantly at the concentration of 3.5 nM with nearly 1000 folds efficacy than CPT-11 (3.0 µM). The results supported that neothalfine might be an anti-tumor lead for further investigation.

Phytochemicals and Allelopathy of Induced Water Hyacinth against Microcystis aeruginosa.

Induced water hyacinth with purple roots (PRWH) exerts a significant inhibitory effect on the growth of blue-green algae. Interestingly, its chemical constituents differ from those of wild-type water hyacinth and have not yet been reported. This study aimed to explore the chemical constituents of PRWH and its bioactive components serving as allelopathic agents against blue-green algae. Phytochemical investigation of the bioactive ethyl acetate fraction of a crude methanol extract from PRWH led to the isolation of 56 compounds, including 11 new phenylphenalene derivatives. The structures of these compounds were elucidated by comprehensive analyses through NMR, HRMS, and X-ray techniques. Bioactivity evaluation against Microcystis aeruginosa indicated that compounds 7, 12, 15, 37, 39, 45, and 47 potently inhibited blue-green algae growth.

Myrothins A-F from Endophytic Fungus Myrothecium sp. BS-31 Harbored in Panax notoginseng.

Endophytic fungi play important roles for host's stress tolerance including invasion by pathogenic microbes. Small molecules are common weapons in the microbe-microbe interactions. Panax notoginseng is a widely used traditional Chinese medicinal plant and harbors many endophytes, some exert functions against pathogens. Here, we report six new compounds named myrothins A-F (1-6) produced by Myrothecium sp. BS-31, an endophyte isolated from P. notoginseng, and their antifungal activities against pathogenic fungi causing host root-rot disease. Their structures were elucidated with analysis of spectroscopic data including 1D and 2D NMR, HR-ESI-MS. Myrothins B (2) and E (5) showed the weak activity against Fusarium oxysporum and Phoma herbarum, and myrothins F (6) showed weak activity against F. oxysporum.

Koninginin W, a New Polyketide from the Endophytic Fungus Trichoderma koningiopsis YIM PH30002.

A new compound named koninginin W (1) and four known polyketides (2-5) were isolated from endophytic fungus Trichoderma koningiopsis YIM PH30002 of Panax notoginseng. The structures of 1 - 5, including absolute configuration of 1, were elucidated on the detailed analysis of the HR-ESI-MS, 1D and 2D NMR, and X-ray crystallographic data. Koninginin W (1) presented weak antibacterial activity against Escherichia coli, Bacillus subtilis and Salmonella typhimurium.

Development of a LC-HRMS based approach to boost structural annotation of isomeric citrus flavanones.

INTRODUCTION: The structural annotation of target relies on high-resolution mass spectrometry (HRMS) information resulting in dubious identities in most cases. The accurate annotation of isomeric structures is still challenging to be confirmed with significant bottleneck. OBJECTIVE: This study focused on the improvement of structural annotation of candidate structures via four pairs of isomeric flavanone-7-O-diglucosides and their basic flavanone aglycones commonly detected in citrus products. METHOD: An integrated liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) approach merging retention time, accurate mass, tandem mass spectrometry (MS/MS) information (diagnostic ions), ion ratio at selected collision energy was established successfully. RESULTS: Feasibility of this approach was validated confidently in biological samples with relative standard deviation (RSD) of ion ratio range from 3.91 to 12.28%. Differences of fragmentation patterns of citrus flavanones were illustrated reasonably. MS/MS fragments of (S)-hesperetin and (S)-isosakuranetin were complicated and showed typical radical ion [1,2 A - H]•- (m/z 164) in negative ESI mode due to the methoxyl group on B-ring, which showed huge difference with (R)-hesperetin and (R)-isosakuranetin. CONCLUSION: This study integrated multiple levels to boost the confidence of structural annotation relied on LC-HRMS, and provided important values in practice for precise identification of citrus flavanones in biological matrices.

The safety and tolerability of alkaloids from Alstonia scholaris leaves in healthy Chinese volunteers: a single-centre, randomized, double-blind, placebo-controlled phase I clinical trial.

CONTEXT: Capsule of alkaloids from the leaf of Alstonia scholaris (L.) R.Br. (Apocynaceae) (CALAS) is a new investigational botanical drug (No. 2011L01436) for bronchitis, post-infectious cough and asthma. OBJECTIVE: To observe the clinical safety and tolerability of CALAS. MATERIALS AND METHODS: Subjects were assigned to eight cohorts, and each received randomly CALAS or placebo in one of single ascending dose (SAD) of 8, 40, 120, 240, 360, 480, or in one of multiple ascending dose (MAD) of 40 or 120 mg, three times daily for 7 days. Each cohort contained two placebo subjects. RESULTS: Sixty-two enrolled volunteers completed the study and no serious adverse events and clinically significant changes in vital signs, electrocardiography, and upper abdominal Doppler ultrasonography were observed. The ratios of treatment-emergent adverse events (TEAEs) were reported in 11/46 (23.91%) of CALAS groups and 3/16 (18.75%) of the placebo group (p > 0.05), respectively, based on the results of SAD and MAD. All TEAEs were mild, transient, and disappeared without any intervention. The TEAEs possibly related to CALAS treatment were as followings: hiccups (4/46: 8%), dry mouth and nausea (3/46: 6%), increased sleep (2/46: 4%), abdominal distension (1/46: 2%), bilirubin elevated (1/46: 2%). DISCUSSION AND CONCLUSIONS: CALAS is safe and well-tolerated with no unexpected or clinically relevant safety concerns up to a single dose of 360 mg and three times daily for 7 days up to 120 mg in healthy Chinese volunteers, supporting further Phase II studies.

Antimicrobial Natural Products Produced by Soil-Derived Fungus Penicillium cremeogriseum W1-1.

Ten compounds (1-10) were obtained from soil-derived Penicillium cremeogriseum W1-1 with the antimicrobial guided isolation procedure. Among them, 4 presented broad-spectrum antimicrobial activities and its preliminary mechanisms were evaluated. Compound 4 showed growth inhibition on drug-resistant pathogenic strains Escherichia coli and Candida albicans with post-contact effect (PCE), changed the morphology and membrane structure, killed cells with leakage, inhibited the growth of C. albicans by eradicating biofilms. Interestingly, the fraction containing 4 presented in vivo anti-pathogenic activities in mice, indicating this indole diterpenoid alkaloid could been used as potential antimicrobial agent.

Total Synthesis of Dactylicapnosines A and B.

Dactylicapnosines A and B, two natural products from Dactylicapnos scandens, exhibited potent anti-inflammatory and analgesic activities both in vitro and in vivo. In this paper, we report our second-generation synthesis of dactylicapnosine A and the first total synthesis of dactylicapnosine B. Our synthetic route features acid-induced isomerization of o-quinone (16), Co-mediated regioselective ring contraction of p-quinone (8b), and oxidative methoxylation of enone (18). This modified sequence provides dactylicapnosine A in 14 steps with an overall yield of 12% from a known compound (14a) and also offers opportunities to synthesize dactylicapnosine-like analogues for biological investigations.

Comparative investigation of phytochemicals among ten citrus herbs by ultra high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry and evaluation of their antioxidant properties.

The citrus herbs have proved their important medicinal and nutritional values as medicine-food dual-purpose herbs, functional foods, or medical herbs in China. In this study, phytochemicals and antioxidant activity among ten typical citrus herbs (ethanol extracts) were investigated comprehensively. The major ingredients and their contents were analyzed by high-resolution mass spectrometry, and the differences of typical fragment ions between flavanone-7-O-rutinoside(s) and flavanone-7-O-neohesperidoside(s) were discriminated properly in negative electrospray ionization mode. Total polyphenols, total flavonoids, 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), and ferric reducing antioxidant power tests were performed, which indicated their beneficial values and antioxidant effects. The medicine-food dual-purpose herbs including Chenpi, Juluo, Daidaihua, Huajuhong, Xiangyuan, and Foshou exhibited antioxidant capacities significantly by decreasing intracellular reactive oxygen species intensity (P < 0.01), enhancing superoxide dismutase, catalase, and glutathione peroxidase activities (P < 0.01) in H2 O2 -induced RIN-m5F cells. Moreover, the functional foods Zhishi, Zhiqiao, and Qingpi showed moderate antioxidant bioactivity, while the medical herb Juhe showed weak antioxidant bioactivity, which were consistent with the multivariate analysis of their major flavonoids. The study provided a new sight for the chemical differentiation and practical application of citrus herbs as medicine-food dual-purpose herbs, functional foods, or medical herbs.

YY1 promotes IL-6 expression in LPS-stimulated BV2 microglial cells by interacting with p65 to promote transcriptional activation of IL-6.

Neuroinflammation plays a critical role in the process of neurodegenerative disorders, during which microglia, the principal resident immune cells in the central nervous system, are activated and produce proinflammatory mediators. Yin-Yang 1 (YY1), a multi-functional transcription factor, is widely expressed in cells of the immune system and participate in various cellular processes. However, whether YY1 is involved in the process of neuroinflammation is still unknown. In the present study, we found that YY1 was progressively up-regulated in BV2 microglial cells stimulated with lipopolysaccharide (LPS), which was dependent on the transactivation function of nuclear factor kappa B (NF-κB). Furthermore, YY1 knockdown notably inhibited LPS-induced the activation of NF-κB signaling and interleukin-6 (IL-6) expression in BV-2 cells, but not mitogen-activated protein kinase (MAPK) signaling. Moreover, YY1 strengthened p65 binding to IL-6 promoter by interacting with p65 but decreased H3K27ac modification on IL-6 promoter, eventually increasing IL-6 transcription. Taken together, these results for the first time uncover the regulatory mechanism of YY1 on IL-6 expression during neuroinflammation responses and provide new lights into neuroinflammation.

Unprecedented sugar bridged bisindoles selective inhibiting glioma stem cells.

Unlike reported bisindoles linked by single bond directly, alstoniasidines A (1) and B (2), from Alstonia scholaris featuring unprecedented skeleton with two indole moieties bridged by a sugar, represented a novel bisindole type having strictosamide-glucopyranose-picraline scaffold. Both compounds exhibited selective cytotoxicity against human glioma stem cells (GSCs) and induced caspase-3 dependent extrinsic apoptosis by increasing the expression of interleukin 1 (IL-1), tumor necrosis factor (TNF-α), and the cleaved caspase-3, while damaged the unlimited proliferation and self-renewal capacity of GSCs. This finding might provide new type of leads for the selective killing of human glioma stem cells.

Isocostunolide inhibited glioma stem cell by suppression proliferation and inducing caspase dependent apoptosis.

Glioblastoma multiform (GBM) is a highly aggressive brain tumor with poor life expectancy, and glioma stem cells (GSCs) are a small population of tumor cells existed in GBM, in which GSCs response to drive GBM recurrence, invasion and contribute to the anti-cancer resistance. GSCs have been identified and developed as a therapeutic target for GBM and can be used in drugs screening. Isocostunolide is a natural sesquiterpenoid and contained abundant resource in medicinal plants, but the anti-cancer efficacies of it against GSCs are still unexplored. In this investigation, the anti-tumor activity of isocostunolide against GSCs was investigated and the result demonstrated that it inhibited the growth of GSCs (GSC-3#, GSC-12#, GSC-18#) significantly with an IC50 value of 2.80µg/ml, 2.61µg/ml, 1.07µg/ml, respectively. In further mechanism study, isocostunolide inhibited GSCs cell proliferation, induced GSCs apoptosis significantly, as well as increased the proportion of the cleavage of caspase-3. The result suggested that isocostunolide induced GSCs apoptosis via the caspase dependent apoptotic pathway. Moreover, isocostunolide damaged GSCs colony formation capacity significantly and exhibited the anti-cancer efficacy against GSCs in vitro.