ABSTRACT
A new siderophore chelate (1) and 8 known compounds were identified from the liquid co-cultures of the marine-derived Streptomyces sp. IMB18-531 and Cladosporium sp. IMB19-099 by a combination of chromatography methods, including C18 reversed-phase medium pressure chromatography, gel column chromatography and HPLC. Their structures were determined by spectroscopic analysis and chemical methods as aluminioxamine E (1), desferrioxamine E (2), ferrioxamine E (3), terragine E (4), capsimicin (5), cyclo(L-prolinyl-L-tyrosine) (6), anthranilic acid (7), (Z)-14-methylpentadec-9-enoic acid (8), and (Z)-hexadec-8-enoic acid (9). Compound 2 showed inhibitory activities against the expression of liver fibrosis related genes COL1A1, MMP2, and TIMP2. Compounds 5, 8, and 9 displayed antibacterial activities against methicillin-resistant Staphylococcus aureus, S. epidermidis and Bacillus subtilis, with MICs of 16-64 μg·mL-1. Compound 5 showed cytotoxicities against human pancreatic cancer MIA Paca-2 and human colon cancer HT-29 cell lines with IC50 of 2.9 and 6.3 μmol·L-1, respectively.
ABSTRACT
Anticancer agents derived from natural products such as various sources like plants, animals and microorganisms. Marine-derived microorganism has become important sources of new bioactive molecules. The products isolated from marine sources possess cytotoxic activities against many cancers. Secondary metabolites as a source of Candida albicans natural drugs many of the medicines prescribed today are natural products obtained from terrestrial plants and microorganisms. The major components (80-90%) of cell wall of are carbohydrates, mannose or polymers of mannose covalently associated with proteins to form glycoproteins. The American Cancer Society has estimated 159,260 deaths due to lung cancer from diagnosis of 224,210 new cases in the United States in 2014. The International Agency for Research on Cancer estimated over 1 million new cancers cases in India in 2012 (10, 14, 934). In this study, we aimed to find new bioactive compounds from crude culture extracts produced by C. albicans as isolated from coastal mangrove ecosystem and docking studies were carried out.
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The basical structure of diketopiperazines is a cyclic dipeptide condensed by two amino acids. Because of the stable framework of the six-member ring structure, and having two hydrogen bond donor and two hydrogen bond receptor, DKPs have become important chemical pharmacophores, with strong biological activities and pharmacological activities in the drug. A series of cyclic compounds were found from marine organisms in recent years, research showed that their functions are not limited on anti-bacterial, cytotoxic activity, and so on, but also playing an important role in regulatory mechanism of quorum sensing as signal molecules, they have become research hot point in ecological chemistry. This paper reviewed the research progress of diketopiperazines found in the marine microbial metabolites, and the future study trends was discussed and outlooked.
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Objective To isolate bioactive compound of enhancing fibrinolysis from secondary metabolites of marine microorganism.Methods The separation of microorganism from seawater samples,screening of producing fibrinolytic compound's strain,selection of the active strain's optimum fermentation medium and refining of active compound were done by the method of selective cultivation,measuring of compound's fibrinolytic activity and semipreparative HPLC,respectively.Results Nine hundred and thirty-six single strains from 31 samples were collected 100 meters off the coast,and cultures of the fungus(FG216) contained enhancing fibrinolytic compound.Compounds from modified Czapek medium as the fermentation medium of FG216 showed significant fibrinolytic effect.Finally,active fraction were isolated and refined from cultures of FG216.Conclusion In this paper,active compound of enhancing fibrinolysis were gained from secondary metabolites of isolated single microorganism from seawater.
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The research of DHA production by marine microorganism culture is active in marine bioactive substances exploitation. The marine microorganism species rich of DHA, the mechanism and influencing factors of DHA synthesizing, the questions and solving method of large scale production are reviewed in this article.
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The apoptosis was observed under a fluoroscope when the tested tumor cells were treated with the supernatant derived from the liquid culture of an actinomyces strain AK 11, which had showed cell toxicity by means of MTT assay, and was further confirmed by the correspondent band of ”DNA ladder” in the agarose gel electrophoresis. In a bioassay employed nude mouse, the pure compound produced by the strain AK 11 showed tumor inhibition in rates of 52.01% and 33.64% corresponding to the dosages of 0.016 ?g?kg -1 and 0.008 ?g?kg -1 ip, respectively. According to the indexes IC 50 of human hepatocarcinoma SMMC7721 and stomach cancer MGC 803 cells, it was estimated that the inhibition effect of the pure compound was slightly stronger than that of Adriamycin. The results showed high antitumor effect of the tested compound from the strain AK 11. When the cells were treated with AK 11, it was found by flow cytometry analysis that cell division was ceased at S phase due to the DNA synthesis block .
ABSTRACT
It is significant for theory and application to study on marine microbial exopolysaccharides with differential structures and activities endowed by the specific marine environment.The recent progress of the research on the structures and bioactivities of marine microbial ex- opolysaccharides was reviewed,and the prospect of the research and development of the marine microbial exopolysaecharides was also expec- ted.