Sudheer Kumar Buddana

Production of polypeptide antibiotic from Streptomyces parvulus and its antibacterial activity

A highly potent secondary metabolite producing actinomycetes strain is isolated from marine soil sediments of Visakhapatnam sea coast, Bay of Bengal. Over all ten strains are isolated from the collected soil sediments. Among the ten actinomycetes strains the broad spectrum strain RSPSN2 was selected for molecular characterization, antibiotic production and its purification. The nucleotide sequence of the 1 rRNA gene (1261 base pairs) of the most potent strain evidenced a 96% similarity with Streptomyces parvulus 1044 strain, Streptomyces parvulus NBRC 13193 and Streptomyces parvulus BY-F. From the taxonomic features, the actinomycetes isolate RSPSN2 matches with Streptomyces parvulus in the morphological, physiological and biochemical characters. Thus, it was given the suggested name Streptomyces parvulus RSPSN2. The active metabolite was extracted using ethyl acetate (1:3, v/v) at pH 7.0. The separation of active ingredient and its purification was performed by using both thin layer chromatography (TLC) and column chromatography (CC) techniques. Spectrometric studies such as UV-visible, FTIR, and NMR and mass were performed. The antibacterial activity of pure compound was performed by cup plate method against some pathogenic bacteria including of streptomycin resistant bacteria like (Pseudomonas mirabilis, Pseudomonas putida and Bacillus cereus). In conclusion, the collected data emphasized the fact that a polypeptide antibiotic (Actinomycin D) was produced by Streptomyces parvulus RSPSN2.

Fibrinolytic, anti-inflammatory and anti-microbial properties of α-(1-3)-glucans produced from Streptococcus mutans (MTCC 497).

Streptococcus mutans (MTCC 497) cell associated α-(1-3)-glucans were isolated, characterized and evaluated for their bioactivity profile. Acid hydrolysis of α-(1-3)-glucans revealed presence of glucose moieties. Water insoluble α-(1-3)-glucans (WIG) were sulfated to convert them into water soluble glucans which were characterized by FT-IR spectral studies. The sulfation of WIG was confirmed by the presence of -O-SO3- and C-O-SO3- characteristic peaks at 1240 and 820 cm(-1). MALDI-TOF analysis of sulfated α-(1-3)-glucan revealed 1.2 to 9kDa fragmentation. Antibacterial profile studies revealed higher growth inhibitory activity against Gram negative than Gram positive bacterial strains by sulfated α-(1-3)-glucans. One-fold higher anti-inflammatory activity with IC50 value of 0.11mg/ml was observed with sulfated α-(1-3)-glucans over WIG. Time dependent fibrinolytic potential without requirement of tissue plasminogen activators was observed for sulfated α-(1-3)-glucans. This is the first report demonstrating the fibrinolytic and anti-inflammatory property for sulfated α-(1-3)-glucans.

Synthesis of novel tetrazole containing hybrid ciprofloxacin and pipemidic acid analogues and preliminary biological evaluation of their antibacterial and antiproliferative activity

A series of 1-substituted-1H-tetrazole-5-thiol building blocks were synthesized and introduced to the N-4 piperazinyl group at C-7 position of the quinolone core, and these novel compounds (5a–g and 8a–g) were screened for their antibacterial and antiproliferative activities. Bioactive assay studies manifested that most of new compounds exhibited significant antibacterial activity against the tested strains, including multi-drug-resistant MRSA in comparison with reference drugs ciprofloxacin, streptomycin B and pipemidic acid. Among the synthesized compounds, only ciprofloxacin (5a–g) derivatives displayed significant activity (

Magnetically Recyclable Nano-Fe2O3-Catalyzed Chemoselective Synthesis and Antioxidant Activity of Diethyl (3-((5-Aryl-1H-1,2,4-triazol-3-yl)thio)propyl)phosphonates

\mathrm{MIC}=15.6~\upmu \hbox {g}/\hbox {mL}

Formation of benzoxanthenones and benzochromenones via cerium-impregnated-MCM-41 catalyzed, solvent-free, three-component reaction and their biological evaluation as anti-microbial agents

MIC=15.6μg/mL) compared to reference drugs. In addition, these compounds were evaluated for their in vitro inhibition of human cancer cell lines viz human cervical carcinoma cell line (SiHA), breast adenocarcinoma (MDA-MB-235) and human pancreas carcinoma (PANC-1) cell lines by using the SRB assay method. Most of the target compounds showed broad potent growth inhibition activity (

Carbohydrate triazole tethered 2-pyridyl-benzimidazole ligands: Synthesis of their palladium (II) complexes and antimicrobial activities

\hbox {GI}_{50}\le ~0.1~\upmu \hbox {M}