Fluorinated s-triazinyl piperazines as antimicrobial agents

A series of 1,3,5-triazine derivatives that contain 4-amino-2-trifluoromethyl-benzonitrile, 8-hydroxyquinoline, and different piperazines as substituents at the carbon atoms of the triazine ring have been synthesized by a simple and efficient synthetic protocol. The chemical structures of the compounds were elucidated with the aid of IR, 1H NMR and 13C NMR spectroscopy, and elemental analysis. The antimicrobial activity of the compounds was tested against seven bacteria (Staphylococcus aureus MTCC 96, Bacillus cereus MTCC 619, Escherichia coli MTCC 739, Pseudomonas aeruginosa MTCC 741, Klebsiella pneumoniae MTCC 109, Salmonella typhi MTCC 733, Proteus vulgaris MTCC 1771) and four fungi (Aspergillus niger MTCC 282, Aspergillus fumigatus MTCC 343, Aspergillus clavatus MTCC 1323, Candida albicans MTCC 183). The results indicate that some of the novel s-triazines have noteworthy activity in minimum inhibitory concentration as well as agar diffusion tests.     

Regioselective synthesis of 3-benzyl substituted pyrimidino chromen-2-ones and evaluation of anti-microbial and anti-biofilm activities

Regioselective synthesis of a number of highly functionalized 3-benzylpyrimidino chromen-2-ones (4) were accomplished in a one pot three component reaction in acetic acid and determined their anti-microbial and anti-biofilm activities. Compounds 4o and 4p showed an excellent anti-microbial activity against Micrococcus luteus MTCC 2470 at a par with standard control (Ciprofloxacin) and exhibited best activity against Staphylococcus aureus MTCC 96 and Bacillus subtilis MTCC 121. Further, compounds 4h, 4i, 4m, 4n and 4q showed promising activity against Micrococcus luteus MTCC 2470, Staphylococcus aureus MTCC 96 and Bacillus subtilis MTCC 121. Whereas, compounds 4m showed very promising biofilm inhibition activity against Staphylococcus aureus MLS 16 MTCC 2940 and 4o, 4p showed very potent activity against Staphylococcus aureus MTCC 96 at a par with Ciprofloxacin used as standard control.     

Optimization of microbiological parameters for enhanced griseofulvin production using response surface methodology

Central composite design was used to determine the optimal levels of microbiological parameters, viz., slant age, seed age and inoculum level, for enhanced griseofulvin production by Penicillium griseofulvum MTCC 1898 and Penicillium griseofulvum MTCC 2004 in shake flask fermentation. The optimal levels of slant age, seed age and inoculum level for Penicillium griseofulvum MTCC 1898 were found to be 8.8772 days, 4.2093 days, 12% (v/v) (᷁.56 kg dry cell mass/m³) and for Penicillium griseofulvum MTCC 2004, 8.221 days, 3.4875 days and 9% (v/v) (̀.09 kg dry cell mass/m³) respectively. The yield of griseofulvin under optimal conditions was found to be 1.65 times for Penicillium griseofulvum MTCC 1898 and 1.07 times for Penicillium griseofulvum MTCC 2004 higher than that obtained using unoptimized conditions. The fermentation time for maximum production of griseofulvin by Penicillium griseofulvum MTCC 1898 and Penicillium griseofulvum MTCC 2004 decreased by 4 days and 2 days respectively.     

Decolourisation and detoxification of synthetic molasses melanoidins by individual and mixed cultures of Bacillus spp

The decolourisation of synthetic melanoidins (i.e., GGA, GAA, SGA, and SAA) by three Bacillus isolates (Bacillus thuringiensis (MTCC 4714), Bacillus brevis (MTCC 4716) and Bacillus sp. (MTCC 6506)) was studied. Significant reduction in the values of physicochemical parameters was noticed alongwith the decolourisation of all four melanoidins (10% v/v). B. thuringiensis (MTCC 4714) caused maximum decolourisation followed by B. brevis (MTCC 4716) and Bacillus sp. (MTCC 6506). A mixed culture comprised of these three strains was capable of decolourising all four melanoidins. The medium that contained glucose as a sole carbon source showed 15% more decolourisation than that containing both carbon and nitrogen sources. Melanoidin SGA was maximally decolourised (50%) while melanoidin GAA was decolourised least ( approximately 06%) in the presence of glucose as a sole energy source. The addition of 1% glucose as a supplementary carbon source was essential for co-metabolism of melanoidin complex. The decolourisation of synthetic melanoidin by three Bacillus spp. significantly reduced the toxicity to the tubificid worm (Tubifex tubifex, Müller).     

Synthesis and characterization of some new quinoline based derivatives endowed with broad spectrum antimicrobial potency

The synthesis of a novel series of 2-(5-(2-chloro-6-fluoroquinolin-3-yl)-3-(aryl)-4,5-dihydro-1H-pyrazol-1-yl)thiazol-4(5H)-ones (4a–l) and N-(4-(2-chloro-6-fluoroquinolin-3-yl)-6-(aryl)pyrimidin-2-yl)-2-morpholinoacetamides (7a–l) are described in the present paper. The chemical structures of compounds have been elucidated by IR, ¹H NMR, ¹³C NMR and mass spectral data. Antimicrobial activity was measured against Escherichia coli (MTCC 443), Pseudomonas aeruginosa (MTCC 1688), Staphylococcus aureus (MTCC 96), Streptococcus pyogenes (MTCC 442), Candida albicans (MTCC 227), Aspergillus niger (MTCC 282) and Aspergillus clavatus (MTCC 1323) by serial broth dilution. Evaluation of antimicrobial activity showed that several compounds exhibited greater activity than reference drugs and thus could be promising new lead molecules.     

FT-IR and GC-MS analyses of potential bioactive compounds of cow urine and its antibacterial activity

The main emphasis of this study was to identify the bioactive compounds responsible for antibacterial activity of Badri cow urine isolated by thin layer chromatography. The most effective bioactive fraction was analysed by FT-IR and GC-MS analyses. Among the four major fractions (EW1, EW2, CA1 and CA2) obtained by TLC profiling, EW1 was found most active against bacterial strains viz., Listeria monocytogenes (MTCC657), Staphylococcus aureus (MTCC7443), Pseudomonas aeruginosa (MTCC424), Klebsiella pneumoniae (MTCC432) and Salmonella typhi (MTCC733). However, Escherichia coli (MTCC118), was found resistant to all the fractions. In FT-IR spectroscopy, functional groups like alcohol, amide, alkene, alkyl halide, polysulfide and phosphate ions were identified. The GC-MS analysis of EW1 fraction exhibited the presence of 12 compounds, of which 1-heneicosanol was found as the major compound. These compounds might be responsible synergistically or individually for antibacterial activity of cow urine. Nine elements namely sodium (Na), calcium (Ca), chromium (Cr), iron (Fe), magnesium (Mg), aluminium (Al), potassium (K) and zinc (Zn), Gold (Au) were measured by ICP-MS analysis.     

Antibiotic resistance and probiotic properties of dominant lactic microflora from Tungrymbai, an ethnic fermented soybean food of India

The present investigation was conducted to assess lactic acid bacteria present in traditionally fermented food of ethnic tribes in India for probiotic properties, antibacterial activity, and antibiotic tolerance behavior. Enterococcus sp., Lactobacillus sp., and Lactococcus sp. showed antibacterial activity against Bacillus cereus MTCC 430, Staphylococcus aureus subsp. aureus MTCC 740, and Salmonella enterica ser. paratyphi A MTCC 735. Lactococcus sp. and Lactobacillus sp. could tolerate acidic conditions (pH 2) and high bile salt concentration (4000 ppm). The lactic microflora were found to be sensitive to most common antibiotics, except for cloxacillin (5 μg), cephalexin (30 μg), and cephalothin (30 μg).     

Co-cultivation of mutant Penicillium oxalicum SAU(E)-3.510 and Pleurotus ostreatus for simultaneous biosynthesis of xylanase and laccase under solid-state fermentation

Co-cultivation of mutant Penicillium oxalicum SAU(E)-3.510 and Pleurotus ostreatus MTCC 1804 was evaluated for the production of xylanase-laccase mixture under solid-state fermentation (SSF) condition. Growth compatibility between mutant P. oxalicum SAU(E)-3.510 and white rot fungi (P. ostreatus MTCC 1804, Trametes hirsuta MTCC 136 and Pycnoporus sp. MTCC 137) was analyzed by growing them on potato dextrose agar plate. Extracellular enzyme activities were determined spectrophotometrically. Under derived conditions, paired culturing of mutant P. oxalicum SAU(E)-3.510 and P. ostreatus MTCC 1804 resulted in 58% and 33% higher levels of xylanase and laccase production, respectively. A combination of sugarcane bagasse and black gram husk in a ratio of 3:1 was found to be the most ideal solid substrate and support for fungal colonization and enzyme production during co-cultivation. Maximum levels of xylanase (8205.31 ± 168.31 IU g(-1)) and laccase (375.53 ± 34.17 IU g(-1)) during SSF were obtained by using 4 g of solid support with 80% of moisture content. Furthermore, expressions of both xylanase and laccase were characterized during mixed culture by zymogram analysis. Improved levels of xylanase and laccase biosynthesis were achieved by co-culturing the mutant P. oxalicum SAU(E)-3.510 and P. ostreatus MTCC 1804. This may be because of efficient substrate utilization as compared to their respective monocultures in the presence of lignin degradation compounds because of synergistic action of xylanase and laccase. Understanding and developing the process of co-cultivation appears productive for the development of mixed enzyme preparation with tremendous potential for biobleaching.     

Endophytic fungal strains of Fusarium solani, from Apodytes dimidiata E. Mey. ex Arn (Icacinaceae) produce camptothecin, 10-hydroxycamptothecin and 9-methoxycamptothecin

Camptothecin and 10-hydroxycamptothecin are two important precursors for the synthesis of the clinically useful anticancer drugs, topotecan and irinotecan. In recent years, efforts have been made to identify novel plant and endophytic fungal sources of camptothecin and 10-hydroxycamptothecin. In this study we have isolated endophytic fungi strains from Apodytes dimidiata (Icacinaceae), a medium sized tree from the Western Ghats, India. The fungi were identified as Fusarium solani using both ITS rDNA sequencing and spore morphology. Two strains, MTCC 9667 and MTCC 9668 were isolated, both of which produced camptothecin and 9-methoxycamptothecin in their mycelia; one of the strains, MTCC 9668 also produced 10-hydroxycamptothecin, though in small amounts. The yields of camptothecin in MTCC 9667 and MTCC 9668 were 37 and 53 μg/100 g, respectively, after 4 days of incubation in broth culture. The yields of 10-hydroxycamptothecin and 9-methoxycamptothecin in MTCC 9668 were 8.2 and 44.9 μg/100 g, respectively. Further research in optimizing the culture conditions of these fungal strains might permit their application for the production of camptothecin and 10-hydroxycamptothecin.     

Enzymatic characteristics of ligninperoxidases from Penicillium citrinum, Fusarium oxysporum and Aspergillus terreus using n-propanol as substrate

The activities of ligninperoxidases from Penicillium citrinum MTCC 3565, Fusarium oxysporum MTCC 3379 and Aspergillus terreus MTCC 3374 have been assayed and the enzymatic characteristics like Km, pH and temperature optima using n-propanol as the substrate have been reported. The results suggest that n-propanol can substitute veratryl alcohol as substrate for assaying ligninperoxidase activities from different fungal strains, without affecting the enzymatic characteristics. The above strains were selected, as they were known to secrete ligninperoxidase in the liquid culture medium.     

Alginate–pectin co-encapsulation of dextransucrase and dextranase for oligosaccharide production from sucrose feedstocks

Bioprocess and Biosystems Engineering - The genes for dextransucrase and dextranase were cloned from the genomic regions of Leuconostoc mesenteroides MTCC 10508 and Streptococcus mutans MTCC 497,...     

Evaluation of the antimicrobial potency of silver nanoparticles biosynthesized by using an endophytic fungus,Cryptosporiopsis ericae PS4

In the present study, silver nanoparticles (AgNPs) with an average particle size of 5.5 ± 3.1 nm were biosynthesized using an endophytic fungus Cryptosporiopsis ericae PS4 isolated from the ethno-medicinal plant Potentilla fulgens L. The nanoparticles were characterized using UV-visible spectrophotometer, transmission electron microscopy (TEM), scanning electron microscopy (SEM), selective area electron diffraction (SAED), and energy dispersive X-ray (EDX) spectroscopy analysis. Antimicrobial efficacy of the AgNPs was analyzed singly and in combination with the antibiotic/antifungal agent chloramphenicol/fluconazole, against five pathogenic microorganisms-Staphylococcus aureus MTCC96, Salmonella enteric MTCC735, Escherichia coli MTCC730, Enterococcus faecalis MTCC2729, and Candida albicans MTCC 183. The activity of AgNPs on the growth and morphology of the microorganisms was studied in solid and liquid growth media employing various susceptibility assays. These studies demonstrated that concentrations of AgNPs alone between 10 and 25 μM reduced the growth rates of the tested bacteria and fungus and revealed bactericidal/fungicidal activity of the AgNPs by delaying the exponential and stationary phases. Examination using SEM showed pits and ruptures in bacterial cells indicating fragmented cell membrane and severe cell damage in those cultures treated with AgNPs. These experimental findings suggest that the biosynthesized AgNPs may be a potential antimicrobial agent.     

Stereoselective first total synthesis, confirmation of the absolute configuration and bioevaluation of botryolide-E

A simple, first stereoselective total synthesis of botryolide-E has been described. The synthesis started from propylene oxide employing Jacobsen’s hydrolytic kinetic resolution (HKR), selective epoxide opening, sharpless asymmetric dihydroxylation, one pot acetonide deprotection and lactonization as key steps. Further, the synthesis confirms the absolute configuration of the natural product botryolide-E and we evaluated the biological behavior of natural product botryolide-E against a panel of bacteria and fungi. Botryolide-E exhibits significant potent activity against Staphylococcus aureus (MTCC 96) (6.25 μg/ml), good against Escherichia coli (MTCC 443) (12.5 μg/ml), Bacillus subtilis (MTCC 441) (25 μg/ml) and compound 1 exhibited good to moderate antifungal activity.     

Drug efficacy of novel 3-O-methoxy-4-halo disubstituted 5,7-dimethoxy chromans; evaluated via DNA gyrase inhibition,bacterial cell wall lesion and antibacterial prospective

In this study, novel 3-O-methoxy-4-halo, disubstituted-5,7-dimethoxy chromans with bacterial cell wall degrading potentials were synthesized, characterized and evaluated as DNA gyrase inhibitors and antibacterial agents. Compounds were showed a broad spectrum of antimicrobial activity against both Gram^+ve bacteria (S. aureus (MTCC 3160), C. diphtheriae (MTCC 116), S. pyogenes (MTCC 442)) and Gram^?ve bacteria (E. coli (MTCC 443), P. aeruginosa (MTCC 424), K. pneumoniae (MTCC 530)). Further, a molecular docking study was carried out to get more insight into the binding mode of present study compounds to target proteins (PDB ID: 2XCT (S. aureus DNA gyrase A), PDB ID: 3G75 (S. aureus DNA gyrase B), PDB ID: 3L7L (Teichoic acid polymerase). In the results, 14?>?20?>?24?>?12?>?18?>?17 were found as the most active against almost all executed activities in this study. The predicted Lipinski’s filter scores, SAR, pharmacokinetic/pharmacodynamics, and ADMET properties of these compounds envisioned the druggability prospects and the necessity of further animal model evaluations of 3-O-methoxy-4-halo disubstituted 5,7-dimethoxy chromans to establish them as an effective and future antibiotics.     

Evaluation of genetic and phenotypic consistency of <Emphasis Type="Italic">Bacillus coagulans</Emphasis> MTCC 5856: a commercial probiotic strain

Commercial probiotics preparation containing Bacillus coagulans have been sold in the market for several decades. Due to its high intra-species genomic diversity, it is very likely that B. coagulans strain may alter in different ways over multiple years of production. Therefore, the present study focuses to evaluate the genetic consistency and probiotic potential of B. coagulans MTCC 5856. Phenotypic and genotypic techniques including biochemical profiling, 16S rRNA sequencing, GTG 5″, BOX PCR fingerprinting, and Multi-Locus-Sequence typing (MLST) were carried out to evaluate the identity and consistency of the B. coagulans MTCC 5856. Further, in vitro probiotic potential, safety and stability at ambient temperature conditions of B. coagulans MTCC 5856 were evaluated. All the samples were identified as B. coagulans by biochemical profiling and 16S rRNA sequencing. GTG 5″, BOX PCR fingerprints and MLST studies revealed that the same strain was present over 3 years of commercial production. B. coagulans MTCC 5856 showed resistance to gastric acid, bile salt and exhibited antimicrobial activity in in-vitro studies. Additionally, B. coagulans MTCC 5856 was found to be non-mutagenic, non-cytotoxic, negative for enterotoxin genes and stable at ambient temperature (25 ± 2 °C) for 36 months. The data of the study verified that the same strain of B. coagulans MTCC 5856 was present in commercial preparation over multiple years of production.     

The impact of bacterial size on their survival in the presence of cationic particles of nano-silver

BackgroundMicrobial surface area is one of the battlegrounds for invading microbes and host defense. Hence, infectious diseases caused by drug resistant microbes with large surface area are more difficult to treat than small size microbes. Nanobiology offers opportunities to re-explore the biological properties of conventional drugs at molecular level to combat these microbes. The purpose of the present study was to examine size depended susceptibility of Gram-positive bacteria towards nano-silver particles.MethodsThis study investigated the growth, surface charge, and morphology of emerging B. megaterium MTCC 7192 and re-emerging S. aureus MTCC 3160 cells in order to observe the susceptibility of these bacteria towards cationic nano-silver particles. Nano-silver particles were applied into wells formed on the Nutrient agar plates containing 10⁸ CFU/mL of the bacteria. Surface potential of normal and treated cells was measured by Microtrac and the effects of nano-silver particles on bacterial cells were assessed by Scanning Electron Microscopy (SEM).ResultsIn this work, synthesized nano-silver particles were found to be more effective against B. megaterium MTCC 7192 than S. aureus MTCC 3160. For B. megaterium MTCC 7192, a 0.30 fold increase in inhibition zone was observed after the addition of nano-silver particles in the wells. From our studies, it is reasonable to state that alternation of zeta potential may affect the cell morphology, which was further confirmed by SEM.ConclusionThe present study concluded that nano-silver particles appears to interact with a larger surface area more effectively.     

Kocuria sediminis sp. nov., isolated from a marine sediment sample

A Gram-positive, pinkish-orange pigmented, coccoid strain, FCS-11^T was isolated from a marine sediment sample taken from Kochi fort area, Kerala, India and subjected to polyphasic taxonomic study. The 16S rRNA gene sequence of the strain was determined and the results of 16S rRNA gene sequence analysis showed that the strain FCS-11^T should be assigned to the genus Kocuria. The chemotaxonomic data supported this taxonomic placement i.e. menaquinones MK-7(H₂), MK-8(H₂) and MK-9(H₂); major fatty acids anteiso C15:0 and iso-C15:0 and phosphatidylglycerol (PG) and diphosphatidylglycerol (DPG) as major polar lipids. Further phylogenetic analysis of the 16S rRNA gene sequence confirmed that the strain FCS-11^T belonged to the genus Kocuria and is closely related to Kocuria turfanensis MTCC 10790^T (99.4%) followed by Kocuria polaris MTCC 3702^T (98.2%), Kocuria rosea MTCC 2522^T (98.2%), Kocuria flava MTCC 10971^T (98.2%), Kocuria aegyptia MTCC 10791^T (98.0%), Kocuria himachalensis MTCC 7020^T (97.5%) and Kocuria atrinae MTCC 10972^T (97.1%). However, the DNA–DNA hybridisation values obtained between strain FCS-11^T and other related strains were well below the threshold that is required for the proposal of a novel species. The G+C content of the genomic DNA was 60.7 mol%. The phenotypic and genotypic data showed that the strain FCS-11^T merits the recognition as a representative of a novel species of the genus Kocuria. It is proposed that the isolate should be classified in the genus Kocuria as a novel species, Kocuria sediminis sp. nov. The type strain is FCS-11^T (= MTCC 10969^T = JCM 17929^T).     

Emulsification and utilization of high-speed diesel by a <Emphasis Type="Italic">Brevibacterium </Emphasis>species isolated from hydraulic oil

Summary A contaminant of hydraulic oil has been isolated and identified using conventional microbiological and biochemical techniques. The PCR amplification and sequencing of 16S-rDNA indicated it to be a Brevibacterium sp. closely related to B. casei strain DSM 20657, based on sequence homology (98%). In view of being an oil contaminant, its ability of high speed diesel (HSD) emulsification and utilization have been studied and compared with two strains of Pseudomonas putida (MTCC2445 and Biotype-A MTCC 1274) and Pseudomonas fluorescens (MTCC670). After enrichment in minimal medium containing HSD as sole source of carbon Brevibacterium sp. (Met-1) was grown in Bushnell Haas broth containing 0.4% HSD (w/v). Bacterial growth at 28 °C, oil utilization, emulsification and surface active properties were determined after 5 days of incubation and compared with type cultures. All bacteria were found to grow well in the presence of HSD at the tested concentration. However, better utilization of HSD was observed in the Brevibacterium Met-1 isolate and Pseudomonas putida (MTCC 2445).     

Characterization of Two Novel Biovar of <Emphasis Type="Italic">Agrobacterium tumefaciens</Emphasis> Isolated from Root Nodules of <Emphasis Type="Italic">Vicia faba</Emphasis>

A total of eight strains of bacteria were isolated from the root nodule of Vicia faba on the selective media of Rhizobium. Two of these strains produced phenotypically distinct mucoid colonies (one slow growing and the other fast growing) and were examined using a polyphasic approach for taxonomic identification. The two strains (MTCC 7405 and MTCC 7406) turned out to be new strains of biovar 1 Agrobacterium rather than Rhizobium, as they showed growth on alkaline medium as well as on 2% NaCl and neither catabolized lactose as the carbon source nor oxidized Tween-80. The distinctness between the two strains was marked with respect to their growth on dextrose and the production of lysine dihydrolase, ornithine decarboxylase and DNA G + C content. 16S rDNA sequencing and their comparison with the 16S rDNA sequences of previously described agrobacteria as well as rhizobia strains confirmed the novelty of the two strains. Both of the strains clustered with strains of Agrobacterium tumefaciens in the 16S rDNA-based phylogenetic tree. The phenotypic and biochemical properties of the two strains differed from those of the recognized biovar of A. tumefaciens. It is proposed that the strains MTCC 7405 and MTCC 7406 be classified as novel biovar of the species A. tumefaciens (Type strains MTCC 7405 = DQ383275 and MTCC 7406 = DQ383276).

Gallotannin hydrolysis by immobilized fungal mycelia in a packed bed bioreactor.

Hydrolysis of gallotannin to gallic acid by immobilized mycelia of Aspergillus niger MTCC 282, Aspergillus fischerii MTCC 150, Fusarium solani MTCC 350 and Trichoderma viride MTCC 167 in a packed bed bioreactor was studied. Fungal mycelia preinduced with 5 g L-1 gallotannin were immobilized in calcium alginate gel (1.5%) and the resultant beads were packed in a column to a bed volume of 175 mm3. Gallotannin dissolved in distilled water was passed through the column and the eluate was recycled after adjusting pH to 6 with ammonium hydroxide (10%). Maximum hydrolysis of gallotannin was recorded by immobilized mycelia of F. solani and T. viride at 35 degrees and 45 degrees C after 175 and 60 min of residency period respectively. Optimum substrate concentration required for maximum hydrolysis was 10 g L-1 at pH 5 for both the fungi. Immobilized mycelia of A. niger and A. fischerii revealed maximum operational stability. Loss of activity after eighth run was in the order of-A. niger (no loss), A. fischerii (7.5%), F. solani (18%) and T. viride (18%). Stability in terms of retention of enzyme activity after 150 days of storage at 4 degrees C was A. niger (58%), A. fischerii (26.8%), F. solani (83%) and T. viride (85.1%).