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Among the actinomycetes in the rare genera, Micromonospora is of great interest since it has been shown to produce novel therapeutic compounds. Particular emphasis is now on its isolation from plants since its population from soil has been extensively explored. The strain CR3 was isolated as an endophyte from the roots of Hieracium canadense, and it was identified as Micromonospora chokoriensis through 16S gene sequencing and phylogenetic analysis. The in-vitro analysis of its extract revealed it to be active against the clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Candida tropicalis (15 mm). No bioactivity was observed against Gram-negative bacteria, Escherichia coli ATCC 25922, and Klebsiella pneumoniae ATCC 706003. The Micromonospora chokoriensis CR3 extract was also analyzed through the HPLC-DAD-UV–VIS resident database, and it gave a maximum match factor of 997.334 with the specialized metabolite BagremycinA (BagA). The in-silico analysis indicated that BagA strongly interacted with the active site residues of the sterol 14-α demethylase and thymidylate kinase enzymes, with the lowest binding energies of − 9.7 and − 8.3 kcal/mol, respectively. Furthermore, the normal mode analysis indicated that the interaction between these proteins and BagA was stable. The DFT quantum chemical properties depicted BagA to be reasonably reactive with a HOMO-LUMO gap of (ΔE) of 4.390 eV. BagA also passed the drug-likeness test with a synthetic accessibility score of 2.06, whereas Protox-II classified it as a class V toxicity compound with high LD50 of 2644 mg/kg. The current study reports an endophytic actinomycete, M. chokoriensis, associated with H. canadense producing the bioactive metabolite BagA with promising antimicrobial activity, which can be further modified and developed into a safe antimicrobial drug. [ABSTRACT FROM AUTHOR]

This study reports the prevalence and antibiotics resistance status of Salmonella detected in raw meat from Lahore, Pakistan. Overall, N = 111 meat samples, were collected from local markets. Salmonella was recovered from 57 (51.35%) samples, including 45.83% of poultry, 60% of buffalo, 64.28% of cow, and 60% of goat meat samples. The predominant Salmonella strains were Salmonella enterica serovars; Typhimurium (45.4%), Typhi (27.2%), and Enteritidis (18.1%), identified by VITEK system and 16S rRNA gene sequencing. The isolates exhibited high resistance to Erythromycin (100%), Cefepime (98.24%), Colistin (94.73%), Azithromycin (92.98%), Tetracycline (87.71%), Polymyxin B (84.21%), Ciprofloxacin (84.21%), Trimethoprim-Sulfamethoxazole (80.70%), Nalidixic Acid (80.70%), Kanamycin (78.94%), Chloramphenicol (77.19%), Streptomycin (71.92%) and Ampicillin (64.91%). While the isolates exhibited more susceptibility to Meropenem (75.43%) and Amikacin (73.68%). N = 8 strains were designated as Multidrug Resistant (MDR) and N = 3 as Extensively Drug-Resistant (XDR) Salmonella. The PCR-based detection of resistance genes revealed the presence of blaTEM-1 gene (100%), catA1 gene (64%), and gyrA gene (18%). The whole genome sequencing (WGS) of two selected strains and subsequent downstream analysis confirmed the strains as MDR and XDR Salmonella enterica serovar Typhi. The study showed that raw meat consumed in Lahore carries a significantly high number of drug-resistant Salmonella. [ABSTRACT FROM AUTHOR]

Filled-skutterudite materials are promising candidates for thermoelectric applications in the intermediate-temperature range to recover waste heat. In this work, mechanical alloying and spark plasma sintering (SPS) techniques were used to consolidate double-filling InxLa0.25Co4Sb12 (x = 0, 0.1, 0.3, 0.5) samples. X-ray diffraction, scanning electron microscopy, and energy-dispersive x-ray spectroscopy were used to analyze the microstructure of the InxLa0.25Co4Sb12 SPS-ed samples. The microstructure results revealed the main phase of the CoSb3 skutterudite structure with a small amount of InSb and CoSb2 attributed to secondary phases. Electrical resistivity remarkably decreased to 9.7 μΩ m at room temperature for the In0.5La0.25Co4Sb12 sample, mainly due to the effective impurity of the InSb nanoinclusions. Moreover, the InSb nanoinclusions yielded a substantial depression in lattice thermal conductivity due to phonon scattering. The reduction in lattice thermal conductivity was approximately 62% for the In0.5La0.25Co4Sb12 sample compared with the La0.25Co4Sb12 sample, resulting in a remarkable enhancement in the dimensionless figure-of-merit (ZT) of 1.25. [ABSTRACT FROM AUTHOR]

Actinobacteria have proven themselves as the major producers of bioactive compounds with wide applications. In this study, 35 actinobacteria strains were isolated from soil samples collected from the Himalayan mountains region in Pakistan. The isolated strains were identified by polyphasic taxonomy and were prioritized based on biological and chemical screening to identify the strains with ability to produce inimitable metabolites. The biological screening included antimicrobial activity against Staphylococcus aureus, Micrococcus luteus, Salmonella enterica, Escherichia coli, Mycobacterium aurum, and Bacillus subtilis and anticancer activity using human cancer cell lines PC3 and A549. For chemical screening, methanolic extracts were investigated using TLC, HPLC-UV/MS. The actinobacteria strain PU-MM93 was selected for scale-up fermentation based on its unique chemical profile and cytotoxicity (50–60% growth inhibition) against PC3 and A549 cell lines. The scale-up fermentation of PU-MM93, followed by purification and structure elucidation of compounds revealed this strain as a promising producer of the cytotoxic anthracycline aranciamycin and aglycone SM-173-B along with the potent neuroprotective carboxamide oxachelin C. Other interesting metabolites produced include taurocholic acid as first report herein from microbial origin, pactamycate and cyclo(L-Pro-L-Leu). The study suggested exploring more bioactive microorganisms from the untapped Himalayan region in Pakistan, which can produce commercially significant compounds. [ABSTRACT FROM AUTHOR]

The thermally driven electrochemical cells (TECs) convert the applied temperature gradient (Δ T) across electrodes, in redox-based electrolytes, into electricity. We, in this report, amplify the power generation characteristics of TEC, maintained at the Δ T of 45 K, by controlling the physical and electrical nature of the polymer membrane. The conductive membrane is prepared by trapping the solution of iodide/triiodide ( I / I ) and 1-butyl-3-methylimidazolium tetrafluoroborate [Cmim][BF] in the mesoporous structure of poly(vinylidene fluoride) membranes. We identify the intricate dependence of TEC performance on numerous thermophysical and electrical properties including thermal conductance, porosity, thickness and ionic resistance of the membrane. Higher thickness provides better thermal resistivity maintaining the TEC at high Δ T; however, this simultaneously reduces the porosity (limiting the redox reactions at the electrodes) and augmenting the membrane resistance. Therefore, a compromise between high thermal gradient and availability of redox species at electrodes improves the maximum power density from 1.5 to 16.3 mW m. [ABSTRACT FROM AUTHOR]

As part of the endeavor for search of effective bioactive compounds, an untapped Arabian Sea environment is selected as a sampling source for the isolation of chemically-talented actinomycete strains. We have isolated an actinomycete strain from the sea sediments belonging to the genus Streptomyces (Accession No. KJ020688) with having potent cytotoxicity (84 %) against brine shrimps nauplii. Isolated strain also showed substantial antibacterial activity against Bacilus subtilis, Escherichia coli and Acinetobacter test strains. Fractions with significant antitumor activity obtained from the extract of 20 l fermentation broth were structurally elucidated and revealed with the production of compounds named as iturin A and actinomycin-D. The cyclic lipopeptide iturin A display outstanding novel antitumor activities against three tumor cell lines viz. HeLa, MCF-7, Hep G2 with IC values of 1.73 ± 0.9, 6.44 ± 0.6 and 8.9 ± 1.09 μg/ml respectively. This peptide is found to be ineffective against RD tumor cells. The second polypeptide actinomycin-D is found to be active against the entire panel of tumor cell lines used. It exhibited stronger activities with IC-values of <0.9 μg/ml against HeLa and MCF-7, while 11.72 ± 0.9 and 1.19 ± 0.8 against Hep G2 and RD cells respectively. Results from the culture optimization experiments of this strain showed greater yield of secondary metabolites while culturing in glucose-yeast extract-malt extract (M2) medium under culture conditions set as follows, shaking at 95 rpm, pH 7.8, incubation temperature 28 °C, for 168 h. As such this is the first report for the isolation of any iturin family member from actinomycetes group with having antitumor activity. [ABSTRACT FROM AUTHOR]

Endophytic actinomycetes from five Asteraceae plants were isolated and evaluated for their bioactivities. From Parthenium hysterophorus, Ageratum conyzoides, Sonchus oleraceus, Sonchus asper and Hieracium canadense, 42, 45, 90, 3, and 2 isolates, respectively, were obtained. Of the isolates, 86 (47.2 %) showed antimicrobial activity. Majority of the isolates were recovered from the roots ( n = 127, 69.7 %). The dominant genus was Streptomyces ( n = 96, 52.7 %), while Amycolatopsis, Pseudonocardia, Nocardia and Micromonospora were also recovered. Overall, 36 of the 86 isolates were significantly bioactivity while 18 (20.9 %) showed strong bioactivity. In total, 52.1 and 66.6 % showed potent cytotoxicity and antioxidant activities. The LC for 15 strains was <20 μg/ml. Compared to the ascorbate standard (EC 0.34 μg/ml), all isolates gave impressive results with notable EC values of 0.65, 0.67, 0.74 and 0.79 μg/ml. [ABSTRACT FROM AUTHOR]

Alpha-theta neurofeedback has been shown to produce professionally significant performance improvements in music students. The present study aimed to extend this work to a different performing art and compare alpha-theta neurofeedback with another form of biofeedback: heart rate variability (HRV) biofeedback. Twenty-four ballroom and Latin dancers were randomly allocated to three groups, one receiving neurofeedback, one HRV biofeedback and one no intervention. Dance was assessed before and after training. Performance improvements were found in the biofeedback groups but not in the control group. Neurofeedback and HRV biofeedback benefited performance in different ways. A replication with larger sample sizes is required. [ABSTRACT FROM AUTHOR]