Publications by authors named "De-Dong Kong"

3 Publications

  • Page 1 of 1

Aerobic denitrification performance and nitrate removal pathway analysis of a novel fungus Fusarium solani RADF-77.

Bioresour Technol 2020 Jan 9;295:122250. Epub 2019 Oct 9.

Department of Tea Science, Zhejiang University, Hangzhou 310058, PR China. Electronic address:

Increasing nitrogenous contaminants have caused immense challenges to the environment and human health. As compared to physical and chemical methods, biological denitrification is considered to be an effective solution due to its environmental friendliness, high efficiency, and low cost. In the present work, a novel fungal strain identified as Fusarium solani (RADF-77) was isolated from cellulose material-supported denitrification reactor; this strain is capable of removing nitrogen under aerobic conditions. The average NO-N removal rate for RADF-77 were 4.43 mg/(L·h) and 4.50 mg/(L·d), when using glucose and tea residue as carbon source, respectively. The nitrogen balance revealed that 53.66% of N vanished via gaseous products. Transcriptional results revealed that respiratory and assimilative nitrate reductases may work together for nitrate removal. Our results indicate that RADF-77 could be used as a potential means of enhancing nitrate-removal performance, as well as recycling tea residue, which is the main byproduct of the manufacture of tea extracts.
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http://dx.doi.org/10.1016/j.biortech.2019.122250DOI Listing
January 2020

Identification and characterization of new Muscodor endophytes from gramineous plants in Xishuangbanna, China.

Microbiologyopen 2019 04 21;8(4):e00666. Epub 2018 Jun 21.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.

The endophytic fungi Muscodor spp. produce volatile organic compounds (VOCs) which can inhibit and even kill pathogenic fungi, bacteria, and nematodes. Nine endophytic fungal strains, isolated from the shoots of gramineous plants including Arthraxon hispidus, Eleusine indica, Oplismenus undulatifolius, and Oryza granulata, were identified as Muscodor through phylogenetic analysis of the internal transcribed spacer. Through an SPSS K-means cluster analysis, the nine Muscodor strains were divided into four groups based on the antifungal activities of the VOCs produced by these fungi determined by a two-section confrontation test. The first group contains the strains Y-L-54, W-S-41, Y-S-35, W-T-27, and Y-L-56, which showed the strongest activity. The second and third groups contain W-S-35 and Y-L-43, which showed stronger and moderate activity, respectively. The fourth group contains W-S-38 and N-L-7, which were the weakest in inhibiting the tested pathogens. Thirty-five compounds and the relative amounts of VOCs were determined by SPME-GC-MS and comparison with the NIST14 mass spectrometry database and Agilent MassHunter qualitative and quantitative analyses. These 35 compounds were classified into two different categories: (a) the product of fatty acid degradation, and (b) the intermediate and final metabolite of the metabolic pathway with the precursor of mevalonic acid. SPSS clustering analysis showed that the chemical components of VOCs might be correlated with their bioactivity rather than their phylogenetic assignment and some of the identified compounds might be responsible for antifungal activity. In conclusion, new Muscodor endophytes were recorded in tropical gramineous plants and a number of strains showed remarkable bioactive properties. Therefore, they have important potential applications in the fields of plant disease control.
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http://dx.doi.org/10.1002/mbo3.666DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6460276PMC
April 2019

In vitro antioxidant activity of phenolic-enriched extracts from Zhangping Narcissus tea cake and their inhibition on growth and metastatic capacity of 4T1 murine breast cancer cells.

J Zhejiang Univ Sci B 2018 Mar.;19(3):199-210

Department of Tea Science, Zhejiang University, Hangzhou 310058, China.

Phenolics, as the main bioactive compounds in tea, have been suggested to have potential in the prevention of various human diseases. However, little is known about phenolics and their bioactivity in Zhangping Narcissue tea cake which is considered the most special kind of oolong tea. To unveil its bioactivity, three phenolic-enriched extracts were obtained from Zhangping Narcissue tea cake using ethyl acetate, n-butanol, and water. Their main chemical compositions and in vitro bioactivity were analyzed by high-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). The ethyl acetate fraction (ZEF) consisted of higher content of phenolics, flavonoids, procyanidins, and catechin monomers (including epigallocatechin gallate (EGCG), epicatechin gallate (ECG), and gallocatechin gallate (GCG)) than n-butanol fraction (ZBF) and water fraction (ZWF). ZEF exhibited the strongest antioxidant capacity in vitro due to its abundant bioactive compounds. This was validated by Pearson correlation and hierarchical clustering analyses. ZEF also showed a remarkable inhibition on the growth, migration, and invasion of 4T1 murine breast cancer cells.
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http://dx.doi.org/10.1631/jzus.B1700162DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5854635PMC
September 2018