RESUMEN
Constitutively expression of the pathway-specific activators is an effective method to activate silent gene clusters and improve natural product production. In this study, nine shunt products of aminoansamycins (1-9) were identified from a recombinant mutant strain S35-LAL by overexpressed the large-ATP-binding regulator of the LuxR family (LAL) gene aas1 in Streptomyces sp. S35. All the compounds showed no anti-microbial, anti-T3SS and cytotoxic activities.
Asunto(s)
Productos Biológicos/metabolismo , Lactamas Macrocíclicas/metabolismo , Familia de Multigenes , Organismos Modificados Genéticamente , Streptomyces/metabolismoRESUMEN
Three new compounds, namely siderochelins D (2), E (3), and F (4), together with one known siderochelin A (1), were isolated from Amycolatopsis sp. LZ149 and elucidated by spectroscopic analyses including1D- and 2D-NMR and X-ray single crystal diffraction. Compounds 1-3 showed antibacterial activity against Mycobacterium smegmatis.
Asunto(s)
Actinobacteria , Química , Antiinfecciosos , Farmacología , Dihidropiridinas , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mycobacterium smegmatisRESUMEN
<p><b>OBJECTIVE</b>To study the chemical constituents from the stem bark of Trewia nudiflora.</p><p><b>METHOD</b>The chemical constituents were isolated by silica gel and sephadex LH - 20 column chromatography, and the structures were elucidated by means of spectral analysis.</p><p><b>RESULT</b>Ten compounds were obtained from EtOAc fraction of EtOH extract and identified as stigmast-4-en-6beta-ol-3-one (1), stigmast-4-en-6alpha-ol-3-one (2), 7beta-hydroxysitosterol (3), 7alpha-hydroxysitosterol (4), schleicheol 2 (5), taraxerone (6), abbeokutone (7), beta-hydroxypropiovanillone (8), o-vanillyl alcohol (9), glycerol monopalmitate (10).</p><p><b>CONCLUSION</b>Compounds 1-5 and 7-9 were isolated from this plant for the first time.</p>
Asunto(s)
Cromatografía en Gel , Medicamentos Herbarios Chinos , Química , Mallotus (Planta) , Química , Corteza de la Planta , Química , Tallos de la Planta , QuímicaRESUMEN
<p><b>OBJECTIVE</b>To study the chemical constituents from herb of Rhodobryum roseum.</p><p><b>METHOD</b>The compounds were isolated by column chromatography, and identified by IR, NMR data.</p><p><b>RESULT</b>8 compounds were isolated and identified. They are piperine (1), caffeic acid methyl ester (2), uracil glucoside (3), ursolic acid (4), 5alpha, 8alpha-epidioxy-methylcholesta-6, 22-dien-3beta-ol (5), 5alpha, 8alpha-epidioxy-methylcholesta-6,9(11), 22-trien-3beta-ol (6), beta-sitosterol (7), daucosterol (8).</p><p><b>CONCLUSION</b>7 compounds (1-6,8) were isolated from this plant for the first time.</p>
Asunto(s)
Alcaloides , Química , Benzodioxoles , Briófitas , Química , Ácidos Cafeicos , Química , Piperidinas , Química , Plantas Medicinales , Química , Alcamidas Poliinsaturadas , Sitoesteroles , Química , Triterpenos , QuímicaRESUMEN
<p><b>OBJECTIVE</b>To determine the content of isopimpinellin in root of Toddalia asiatica.</p><p><b>METHODS</b>A HPLC method was set up. Using Hypersil C18 column and methanol-water (70:30) as mobile phase, with the detection wavelength at 306 nm.</p><p><b>RESULT</b>The linear range of isopimpinellin was 0.004 20 approximately 0.420 microg. The average recovery was 99.7% and the RSD 2.8%.</p><p><b>CONCLUSION</b>The method is simple and accurate, with good reproducibility, and can be used as a quantitative analysis method for isopimpinellin.</p>
Asunto(s)
Cromatografía Líquida de Alta Presión , Furocumarinas , Raíces de Plantas , Química , Plantas Medicinales , Química , Rutaceae , QuímicaRESUMEN
Mycoepoxydiene is a novel antitumor agent extracted from marine lignicolous fungi HLY-2, which is Diaporthe phaseolorum by molecule identification. The medium optimization for mycoepoxydiene by orthogonal design and the comparison of submerged fermentation and solid state fermentation were studied. The rusult is that the maximal yield of the compound is 543mg/L, which is 43 times compared to the customary half-seawater PD medium and 15 times to the best submerged condition. This optimum culture medium included potato 250g/L, seawater 300mL/L, glucose 30g/L, lactose 50g/L, KH_ 2 PO_ 4 0.65mmol/L and (NH_ 4 )_ 2 SO_ 4 1g/L in the solid state condition. Differentiation analysis between submerged and solid state fermentation, and antitumor activity of these ferment products were also studied. The antitumor activity of products of the optimum medium approached the pure compound.