Structure elucidation and NMR assignments of an alkaloid from <i>Ixeris chinensis</i> Nakai

<p>A new alkaloid, 2-amino-1,6-dihydro-pyridine-5-carbaldehyde (<b>1</b>), together with four known compounds, namely 4-hydroxybenzaldehyde (<b>2</b>), 4-hydroxyacetophenone (<b>3</b>), acetophenone-4-O-<i>β</i>-d-glucoside (<b>4</b>), 2-hydroxyl-6-methoxyacetophenone-4-O-<i>β</i>-d-glucoside (<b>5</b>), were isolated from the CHCl₃ extract from <i>Ixeris chinensis</i> Nakai. The structures of <b>1</b> was elucidated by spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1D and 2D NMR techniques.</p

Additional file 1 of Improved consolidated bioprocessing for itaconic acid production by simultaneous optimization of cellulase and metabolic pathway of Neurospora crassa

Additional file 1: Figure S1. Main plasmids used in this study. (A) Plasmids pMF-272-Pccg1/Peas/Pcbh1/Pgh6-2/Pgh11-2/Ptef1/Pgpd/Ppda-CAD were used to compare the expression of CAD in N. crassa. (B) Plasmids pMF-272-Pccg1-CBH1/GH6-2/GH5-1/GH3-4/AsBGA/TrCBH2 were used to compare the effects of different cellulases. (C) Plasmids pMF-272-Pccg1-CAD-Pcbh1-CBH1/GH6-2/GH5-1/GH3-4/AsBGA/TrCBH2 were used to compare the effects of different cellulase and CAD co-expression. (D) Plasmid pMF-272-Pccg1-MTK was used to verify the expression of MTK in N. crassa. The plasmids pUC19-MTK-HPH (F) and pMF-272-Pccg1-CAD-Pes-MCL (E) or pMF-272-Pccg1-CAD-Pcbh1-MTTA-Pes-MCL (G) were used to construct N. crassa PMF-CAD-rGS or N. crassa PMF-CAD-MTTA-rGS. (H) Plasmid pMF-272-Pccg1-CAD-Pcbh1-MTTA-Pcbh1-TrCBH2 was used to construct N. crassa PMF-CAD-MTTA-TrCBH2. Figure S2. PCR amplified the promoter sequence. Figure S3. Strain construction process using Pcbh1 as the CAD promoter. (A) Pcbh1 promoter sequence was amplified by PCR. M:Trans2K Plus DNA Marker, 1–6:Pcbh1 (B) PCR identification of vector Blunt-Pcbh1. 1–22: Blunt-Pcbh1 (C) Identification of recombinant plasmid pMF272-CAD. 1–6: pMF272-CAD. (D) Double enzyme digestion of pMF272-CAD recombinant plasmid. (E) Cloning vector Blunt-Pcbh1 double enzyme digestion. (F) Colony PCR identification of recombinant plasmid pMF-CAD-Pcbh1. Figure S4. Construction of cellulase overexpression strain. (A) PCR amplification of Pcbh-1 promoter sequence (1 and 2), gh3-4 sequence (4), and cbh1 sequence (B, 1 and 2). (C) Identification of expression vector containing cbh1 gene. (D) PCR screening of gh3-4 gene expression vectors. (E) Genome PCR for vector transformation screening 1,2,3: cbh1; 4,5: gh3-4. Figure S5. Construction of MTK, MCL expression strain. (A) PCR amplification of MTK (lines 1 ~ 3). (B) Colony PCR for identification of MTK expression cassette (C) PCR amplification of GFP (1) and terminator fragments (2). Identification of expression vector containing cbh1 gene. Genome PCR for MTK expression (D) and MCL expression (E) vector transformation screening. Figure S6. Construction of CAD, MTK and MCL co-expression strain. (A) PCR amplification of 5′ fragment (lines 1 ~ 3). (B) PCR amplification of 3′ fragment (lines 1 ~ 3) and hph fragment (lines 4 and 5). (C) PCR amplification of MTK cassette. (D) Identification of expression vector containing 5′ fragment and hph fragment. Table S1. Plasmids used in this study. Table S2. Strains used in this study. Table S3. Primer list of CAD expression and promoter optimization. Table S4. Primer list of cellulase expression. Table S5. Primer list of CAD and cellulase co-expression. Table S6. Primer list of MTK, MCL and MTTA expression. Table S7. RT-PCR Primers

Solid-State Luminescence Turn-On Sensing Using MOF-Confined Reporter–Spacer–Receptor Architectures Facilitated by Quencher Displacement

The reporter–spacer–receptor (RSR) approach is prevalent to develop molecular turn-on sensors. However, the fluorescent RSR sensors barely operate in solid state, which hinders their fabrication into devices for practical applications. Herein, we present a novel strategy to achieve solid-state luminescence turn-on sensing by assembling RSR architectures within MOF frameworks. Unlike the regular RSR systems, the framework-confined fluorophore and receptor are well arranged and separated even in the solid state. This concept is illustrated by a multicomponent MOF (Fc@NU-1000), which contains organic linkers with a highly luminescent pyrene core as the reporter, Zr6 nodes with unsaturated sites as the receptor, and the incorporated Fc molecules as the quencher. The separate incorporation of pyrene core and Fc in the multicomponent MOF favors an efficient pseudointramolecular photoinduced electron transfer (PET) process, resulting in significant luminescence quenching. Interestingly, such PET process can be blocked via the quencher displacement initiated by the phosphate analyte, therefore recovering the solid-state luminescence of MOF microcrystals. We found that Fc@NU-1000 is shown as a sensitive solid-state luminescence turn-on probe for phosphate with the naked-eye response at a low content. What’s more, this study is the first example of confining a quencher displacement-based RSR system in the MOF framework for solid-state luminescence turn-on sensing, thus also providing new opportunities for MOF materials to develop luminescence turn-on sensors

Sacculatane Diterpenoids from the Liverwort Plagiochila nitens Collected in China

Seven new terpenoids, including six sacculatane diterpenoids plagiochilarins A–F (1–6), and one ent-2,3-seco-aromandrane sesquiterpenoid plagiochilarin H (8) with a 6/7/3/5 tetracyclic scaffold, alongside three known compounds, were obtained from the Chinese liverwort Plagiochila nitens Inoue. Plagiochilarin B (2) was unpredictably converted to the more stable artifact 7 under acid catalysis through cyclic ether formation. The reaction mechanism was reasonably deduced and experimentally verified. The structures of these terpenoids were determined by analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction. The inhibitory effect of all of the isolates was evaluated on the growth of two C. albicans strains, wild strain SC5314 and efflux pump-deficient strain DSY654. However, only plagiochilarin H (8) showed a MIC value of 16 μg/mL against C. albicans DSY654

Sacculatane Diterpenoids from the Liverwort Plagiochila nitens Collected in China

Seven new terpenoids, including six sacculatane diterpenoids plagiochilarins A–F (1–6), and one ent-2,3-seco-aromandrane sesquiterpenoid plagiochilarin H (8) with a 6/7/3/5 tetracyclic scaffold, alongside three known compounds, were obtained from the Chinese liverwort Plagiochila nitens Inoue. Plagiochilarin B (2) was unpredictably converted to the more stable artifact 7 under acid catalysis through cyclic ether formation. The reaction mechanism was reasonably deduced and experimentally verified. The structures of these terpenoids were determined by analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction. The inhibitory effect of all of the isolates was evaluated on the growth of two C. albicans strains, wild strain SC5314 and efflux pump-deficient strain DSY654. However, only plagiochilarin H (8) showed a MIC value of 16 μg/mL against C. albicans DSY654

Sacculatane Diterpenoids from the Liverwort Plagiochila nitens Collected in China

Seven new terpenoids, including six sacculatane diterpenoids plagiochilarins A–F (1–6), and one ent-2,3-seco-aromandrane sesquiterpenoid plagiochilarin H (8) with a 6/7/3/5 tetracyclic scaffold, alongside three known compounds, were obtained from the Chinese liverwort Plagiochila nitens Inoue. Plagiochilarin B (2) was unpredictably converted to the more stable artifact 7 under acid catalysis through cyclic ether formation. The reaction mechanism was reasonably deduced and experimentally verified. The structures of these terpenoids were determined by analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction. The inhibitory effect of all of the isolates was evaluated on the growth of two C. albicans strains, wild strain SC5314 and efflux pump-deficient strain DSY654. However, only plagiochilarin H (8) showed a MIC value of 16 μg/mL against C. albicans DSY654

Sacculatane Diterpenoids from the Liverwort Plagiochila nitens Collected in China

Seven new terpenoids, including six sacculatane diterpenoids plagiochilarins A–F (1–6), and one ent-2,3-seco-aromandrane sesquiterpenoid plagiochilarin H (8) with a 6/7/3/5 tetracyclic scaffold, alongside three known compounds, were obtained from the Chinese liverwort Plagiochila nitens Inoue. Plagiochilarin B (2) was unpredictably converted to the more stable artifact 7 under acid catalysis through cyclic ether formation. The reaction mechanism was reasonably deduced and experimentally verified. The structures of these terpenoids were determined by analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction. The inhibitory effect of all of the isolates was evaluated on the growth of two C. albicans strains, wild strain SC5314 and efflux pump-deficient strain DSY654. However, only plagiochilarin H (8) showed a MIC value of 16 μg/mL against C. albicans DSY654

Sacculatane Diterpenoids from the Liverwort Plagiochila nitens Collected in China

Seven new terpenoids, including six sacculatane diterpenoids plagiochilarins A–F (1–6), and one ent-2,3-seco-aromandrane sesquiterpenoid plagiochilarin H (8) with a 6/7/3/5 tetracyclic scaffold, alongside three known compounds, were obtained from the Chinese liverwort Plagiochila nitens Inoue. Plagiochilarin B (2) was unpredictably converted to the more stable artifact 7 under acid catalysis through cyclic ether formation. The reaction mechanism was reasonably deduced and experimentally verified. The structures of these terpenoids were determined by analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction. The inhibitory effect of all of the isolates was evaluated on the growth of two C. albicans strains, wild strain SC5314 and efflux pump-deficient strain DSY654. However, only plagiochilarin H (8) showed a MIC value of 16 μg/mL against C. albicans DSY654