Characterization of cytotoxic compound from marine sediment derived actinomycete Streptomyces avidinii strain SU4.

Research Scholar, Department of Biotechnology, Sathyabama University, Jeppiaar Nagar, Rajiv Gandhi Salai, Chennai-600 119, India.
Asian Pacific Journal of Tropical Biomedicine 10/2012; 2(10):770-3. DOI: 10.1016/S2221-1691(12)60227-5
Source: PubMed

ABSTRACT To investigate the cytotoxic activity of actinomycete isolated from marine sediment.
In the present study the DNA was isolated and the ITS region of 16s rRNA was amplified by polymerase chain reaction, using two universal bacterial primers, 1492R (5'-GGTTACCTTGTTAC GACTT-3') and Eubac27F (5'-AGAGTTTGATCCTGGCTC AG-3'). The amplified products were purified using TIANgel mini purification kit, ligated to MD18-T simple vector (TaKaRa), and transformed into competent cells of Escherichia coli DH5α. 16S rRNA gene fragment was sequenced using forward primer M13F (-47) and reverse primer M13R (-48). Blast search sequence similarity was found against the existing non-redundant nucleotide sequence database thus, identified as Streptomyces sp SU, Streptomyces rubralavandulae strain SU1, Streptomyces cacaoi strain SU2, Streptomyces cavourensis strain SU3, Streptomyces avidinii strain SU4, Streptomyces globisporus strain SU5, Streptomyces variabilis strain SU6, Streptomyces coelicolor strain SU 7. Among the eight identified isolates, one actinomycete Streptomyces avidinii strain SU4 was selected for further study.
Crude extract of the actinomycete isolate exhibited IC50 in 64.5 µg against Hep-2 cell line, 250 µg in VERO cell line. This value is very close to the criteria of cytotoxicity activity for the crude extracts, as established by the American National Cancer Institute (NCI) is in IC50 < 30 µg/mL. The GC MS analysis showed that the active principle might be 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester (12.17%), isooctyl phthalate (15.29%) with the retention time 15.642 and 21.612, respectively.
This study clearly proves that the marine sediment derived actinomycetes with bioactive metabolites can be expected to provide high quality biological material for high throughout biochemical and anticancer screening programs. These results help us to conclude that the potential of using metabolic engineering and post genomic approaches to isolate more bioactive compounds and make their possible commercial application is not far off.

1 Follower
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we report a method of extraction, identification of major bioactive metabolites from endophytic fungi Alternaria alternata ethanol extract using an in vitro antimitotic assay, antiproliferative and DNA fragmentation assays. The fraction 6 of A. alternata ethanol extract strongly inhibited the onion meristematic cells, inhibited the yeast cells and induced the DNA fragmentation in yeast cells. To know the bioactive compounds in the 6 th fraction from 7 different peaks found in GC-MS analogues based on retention time, the compounds are 2-benezenedicarboxylic acid, bis (2-methylpropyl) ester, hexadecanoic acid, methyl ester, 1,2 benzenedicarboxylic acid, butyl 2-methylpropyl ester, 1,4-napththalenedione, 2-hydroxy-3-(3-methyl-2-butenyl)-, 9-octadecenoic acid (Z), methyl ester, 10,13-octadecadienoic acid, methyl ester and 1,2-benzenecarboxylic acid. The antimitotic, antiproliferative and DNA fragmentation assay may be due to the presence of potent bioactive compounds may occur in exclusively or combination. Further work is needed to identify the exact compound that may be used for cancer therapy. INTRODUCTION Fungal endophytes are micro-organisms that colonize living, internal tissues of plants without causing any immediate and overt negative effects (Bacon and White, 2000). The fungal endophytes have proven to be promising sources of many biologically active natural products (Strobel, 2002). Tabebuia argentea (Bignoniaceae) is a large and yellow flowering tree and have proven be rich sources of many organic compounds viz., phenolic, polyphenolic and lapachol. This plant is able to produce an anticancer agent Corresponding Author
  • [Show abstract] [Hide abstract]
    ABSTRACT: To study the phytochemical screening and antibacterial activity of the stem bark extracts of Khaya senegalensis (K. senegalensis) against Salmonella enterica subsp. enterica serovar Typhi.
    Asian Pacific Journal of Tropical Biomedicine 05/2014; 4(Suppl 1):S279-83. DOI:10.12980/APJTB.4.2014C636
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Marine Streptomyces ruber EKH2 isolated from sediments of Bardawil Lake, Egypt, was found as a promising strain for producing bioactive metabolite(s) working against some virulent fish pathogens. Some biochemical and morphological characterizations of marine S. ruber EKH2 were carried out. Cell free culture showed activities against the tested pathogens ranging from 15 to 30 mm. Optimized conditions for maximum activities were observed at neutrality and temperature 28 °C against the tested strains. Two grams of the ethyl acetate crude extract from 10 L culture supernatant was chromatographically separated into three fractions and bioassayed. One major antibacterial compound was separated exhibiting MIC average 12.5 μg/ml. Phthalic acid was structurally suggested on the basis of gas chromatography–mass spectrum (GC–MS) and infrared spectrum (IR). Phthalate activities were compared with known standard antibiotics used in fish therapy and found to be superior. A slight toxicity of phthalate against brine shrimp (LC50 = 2800 μg/ml) was observed. Dealing with pan-drug resistant bacteria in fish therapy, this study confirmed that marine S. ruber EKH2 is potentially used for extracting phthalic acid as a novel bioactive and non-toxic agent for treating bacterial fish infections.

Full-text (2 Sources)

Available from
Jun 5, 2014