A new quaternary protoberberine alkaloid isolated from <i>Dicranostigma leptopodum</i> (Maxim) Fedde

<div><p>Phytochemical investigation of the whole plants of <i>Dicranostigma leptopodum</i> (Maxim) Fedde has led to the isolation of two quaternary protoberberine alkaloids 5-hydroxy-coptisine (<b>1</b>) and berberrubine (<b>2</b>). This type of alkaloids was isolated from the genus <i>Dicranostigma</i> for the first time and the new compound structure (<b>1</b>) was elucidated by various spectroscopic methods including 2D NMR techniques (gCOSY, HMQC and HMBC) and HR-ESI-MS.</p></div

Talaromycolides A–C, Novel Phenyl-Substituted Phthalides Isolated from the Green Chinese Onion-Derived Fungus Talaromyces pinophilus AF-02

The green Chinese onion (Allium fistulosum L.), which is widely cultivated and has been naturalized in many places, is an important spice and vegetable in East and Southeast Asia. It is used to treat the common cold in China. In the ongoing search for antibacterial activity in fungi derived from natural, pungently scented vegetables, the secondary metabolites of Talaromyces pinophilus AF-02, which was isolated from the stem of the green Chinese onion, were investigated. The genus <i>Talaromyces</i> (Trichocomaceae) is an important fungal genus because of its ubiquity and the role of many of its species in food and agriculture production. Three new phthalide derivatives, talaromycolides A–C, <b>1</b>–<b>3</b>; a new long-chain dicarboxylic acid, <b>11</b>; and 12 known compounds were isolated from methanolic extracts of this fungus. Their structures were determined via extensive NMR, HR-ESI-MS, and CD spectroscopic analyses. Compounds <b>1</b>–<b>3</b> are rare phthalide derivatives with a novel linkage position between the phenyl and phthalide moieties. The biological properties of <b>1</b>–<b>16</b> were evaluated using six different bacteria, and <b>1</b>–<b>3</b>, <b>5</b>, and <b>11</b> exhibited significant antibacterial activity in response to some of the tested strains

Isolation of Secondary Metabolites from the Soil-Derived Fungus <i>Clonostachys rosea</i> YRS-06, a Biological Control Agent, and Evaluation of Antibacterial Activity

The fungus <i>Clonostachys rosea</i> is widely distributed all over the world. The destructive force of this fungus, as a biological control agent, is very strong to lots of plant pathogenic fungi. As part of the ongoing search for antibiotics from fungi obtained from soil samples, the secondary metabolites of <i>C. rosea</i> YRS-06 were investigated. Through efficient bioassay-guided isolation, three new bisorbicillinoids possessing open-ended cage structures, tetrahydrotrichodimer ether (<b>1</b>) and dihydrotrichodimer ether A and B (<b>2</b> and <b>3</b>), and 12 known compounds were obtained. Their structures were determined via extensive NMR, HR-ESI-MS, and CD spectroscopic analyses and X-ray diffraction data. Compounds <b>1</b>–<b>3</b> are rare bisorbicillinoids with a γ-pyrone moiety. The biological properties of <b>1</b>–<b>15</b> were evaluated against six different Gram-positive and Gram-negative bacteria. Bisorbicillinoids, <b>2</b>–<b>5</b>, and TMC-151 C and E, <b>14</b> and <b>15</b>, showed potent antibacterial activity

An overview of recent progress in elution mode of counter current chromatography

Countercurrent chromatography (CCC) is a developing chromatographic technique that achieves separation based on the distribution of the target in an immiscible biphasic or multiphasic solvent system. In the past decades, this technique has advanced greatly in application and theory. This overview is mainly focused on the development of elution modes, which have been easily achieved with the classical CCC apparatus in recent years. It includes gradient elution, dual-mode elution, multiple dual-mode elution, recycling elution, extrusion elution, cocurrent elution and pH zone refining. The basic principles of each elution mode are described in detail and then summarized. The comparison and the scope of application of these elution modes are also discussed.The financial support of the National Natural Science Foundation of China (NSFC No. 21175142 and No. 21505144) and Open Fund of Key Laboratory of Chemistry of Northwestern Plant Resources of the Chinese Academy of Sciences (No. CNPR-2011kfkt-02) is acknowledged. Dr X.-Y Huang is also grateful for the financial support from CAS to undertake overseas academic visits; he also acknowledges the Advanced Bioprocessing Centre at Brunel University, UK, for presenting the opportunity to study at Brune