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      A quantitative analytical method for valienone and its application in the evaluation of valienone production by a breakthrough microbial process

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          Valienone is a significant natural carbasugar member of the C7-cyclitol family as a valuable precursor for glycosidase inhibitor drugs. It is an intermediate of validamycin A biosynthesis pathway and exhibits minimal accumulation in the fermentation broth of the natural Streptomyces producer. A quantitative analytical method is crucial for the development of a breakthrough microbial process overcoming the consumption of the natural metabolic flux. The present study was designed to develop a pre-column derivatization high-performance liquid chromatography method for quantification of valienone and to help establish a straightforward fermentation process for valienone production by metabolically engineered Streptomyces hygroscopicus 5008. Valienone was derivatized by 2, 4-dinitrophenylhydrazine (DNPH) in 10 mmol·L −1 H 3PO 4 at 37 °C for 45 min and the derivatives were separated on Eclipse XDB-C 18 (5 μm, 4.6 mm × 150 mm) column at 30 °C eluted with 50% acetonitrile for 18 min. The derivatives were detected by diode array detector at 380 nm and the configurations of the derivatives were determined by computational studies. The method was shown to be effective, sensitive, and reliable. Good linearity was found in the range of 5–2 000 μg·mL −1. The intra- and inter-day precisions were 1.1%–2.7% and 1.7%–2.2%, respectively. The absolute recovery of the spiked samples was 97.2%–102.6%. To date, this is the first reversed-phase high-performance liquid chromatography detection method for valienone in microbial culture medium. This method successfully helped evaluate the valienone production capability of the engineered Streptomyces hygroscopicus 5008 and could be promising for C7-cyclitol profiling of different engineered mutants combined with the metabonomics methods.

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          • Record: found
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          Methods for the determination of limit of detection and limit of quantitation of the analytical methods

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            Voglibose for prevention of type 2 diabetes mellitus: a randomised, double-blind trial in Japanese individuals with impaired glucose tolerance.

            The increased prevalence of type 2 diabetes mellitus is a major concern for health providers. We therefore assessed whether voglibose, an alpha-glucosidase inhibitor, could prevent the development of type 2 diabetes in high-risk Japanese individuals with impaired glucose tolerance. 1780 eligible patients on a standard diet and taking regular exercise with impaired glucose tolerance were randomly assigned to oral voglibose 0.2 mg three times a day (n=897) or placebo (n=883) in a multicentre, double-blind, parallel group trial. Treatment was continued until participants developed type 2 diabetes (primary endpoint) or normoglycaemia (secondary endpoint), or for a minimum of 3 years, subject to the findings of an interim analysis. Analysis was by full analysis set. This trial is registered with the University Hospital Medical Information Network (UMIN) clinical trials registry, number UMIN 000001109. In the interim analysis, voglibose was better than placebo (p=0.0026) in individuals treated for an average of 48.1 weeks (SD 36.3). Patients treated with voglibose had a lower risk of progression to type 2 diabetes than did those on placebo (50 of 897 vs 106 of 881; hazard ratio 0.595, 95% CI 0.433-0.818; p=0.0014). More people in the voglibose group achieved normoglycaemia than did those in the placebo group (599 of 897 vs 454 of 881; 1.539, 1.357-1.746; p<0.0001). 810 (90%) of 897 patients in the voglibose group had adverse events versus 750 (85%) of 881 in the placebo group. Serious adverse events (all one each) in the voglibose group were cholecystitis, colonic polyp, rectal neoplasm, inguinal hernia, liver dysfunction, and subarachnoid haemorrhage, and in the placebo group were cerebral infarction and cholecystitis. Voglibose, in addition to lifestyle modification, can reduce the development of type 2 diabetes in high-risk Japanese individuals with impaired glucose tolerance. Takeda.
              • Record: found
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              α- and β-Glucosidase inhibitors: chemical structure and biological activity


                Author and article information

                Chinese Journal of Natural Medicines
                20 October 2017
                : 15
                : 10
                : 794-800
                State Key Laboratory of Microbial Metabolism, School of Life Science & Biotechnology, and Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
                Author notes
                *Corresponding author: FENG Yan, Tel: 86-21-34207189, E-mail: yfeng2009@ ; BAI Lin-Quan, Tel: 86-21-34206722, E-mail: bailq@

                These authors have no conflict of interest to declare.

                Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.
                Funded by: Science and Technology Commission of Shanghai Municipality
                Award ID: 14JC1403500
                Funded by: National Science Foundation of China
                Award ID: 31200061
                Funded by: Research Fund for the Doctoral Program of Higher Education
                Award ID: 13Z102090066
                This work was supported by Science and Technology Commission of Shanghai Municipality (No. 14JC1403500), National Science Foundation of China (No. 31200061), and Research Fund for the Doctoral Program of Higher Education (No. 13Z102090066).


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