scholarly journals Uncovering the potential of actinobacterium BLH 1-22 isolated from marine sediment as a producer of antibiotics

2021 ◽  
Vol 948 (1) ◽  
pp. 012056
Author(s):  
A Atikana ◽  
S Ratnakomala ◽  
I Nurzijah ◽  
M N Sari ◽  
A Agnestania ◽  
...  
Keyword(s):  
Marine Sediment ◽  
High Performance ◽  
Micrococcus Luteus ◽  
Antimicrobial Compounds ◽  
Antibacterial Screening ◽  
Crude Extracts ◽  
Hplc Profile ◽  
Micromonospora Chalcea ◽  
Comprehensive Study

Abstract Actinobacteria have been known as producers of many bioactive compounds. The present study examines ten marine Actinobacterial isolates, aiming to investigate their potential as producers of antimicrobial compounds. The secondary metabolites were extracted from these Actinobacteria using ethyl acetate, and the crude extracts were tested for their bioactivity against Escherichia coli, Bacillus subtilis, and Micrococcus luteus. The antibacterial screening showed that the crude extracts of these Actinobacteria inhibit the growth of indicator strains. The extracts of isolate BLH 1-22 were further analysed using high-performance liquid chromatography (HPLC), which showed potential compounds with peak and retention time similar to the antibiotic standards (i.e., erythromycin, ampicillin, tetracycline, and penicillin). In addition to the HPLC profile, molecular identification showed that the isolate BLH 1-22 was similar to Micromonospora chalcea (99.6%). Further genome characterization of the strain, as well as purification and fractionation of the metabolite extracts, are important to obtain a comprehensive study on the potential of isolate BLH 1-22 as antibiotic compound producers. This study reported the potential of Micromonospora BLH 1-22 isolated from marine sediment. Hence, it also highlighted the potential of Actinobacteria isolated from Indonesian environments for bioprospecting studies.

Phytochemical characterization of antimycobacterial crude extracts from medicinal plants traditionally used in Mozambique

Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
X Luo ◽  
D Pires ◽  
JA Aínsa ◽  
B Gracia ◽  
S Mulhovo ◽  
...  
Keyword(s):  
Medicinal Plants ◽  
Crude Extracts

Preparation and Characterization of NH2-Terminal Fibrinogen Bβ Fragments from N-DSK of Human Fibrinogen

1984 ◽  
Vol 51 (01) ◽  
pp. 016-021 ◽  
Author(s):  
S Birken ◽  
G Agosto ◽  
B Lahiri ◽  
R Canfield
Keyword(s):  
High Performance ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Reverse Phase ◽  
Human Fibrinogen ◽  
Human Volunteers ◽  
Cnbr Cleavage ◽  
Two Peaks

SummaryIn order to investigate the early release of NH2-terminal plasmic fragments from the Bβ chain of fibrinogen, substantial quantities of Bβ 1-42 and Bβ 1-21 are required as immunogens, as radioimmunoassay standards and for infusion into human volunteers to determine the half-lives of these peptides. Towards this end methods that employ selective proteolytic cleavage of these fragments from fibrinogen have been developed. Both the N-DSK fragment, produced by CNBr cleavage of fibrinogen, and Bβ 1-118 were employed as substrates for plasmin with the finding of higher yields from N-DSK. Bβ 1-42 and Bβ 1-21 were purified by gel filtration and ion-exchange chromatography on SP-Sephadex using volatile buffers. When the purified preparation of Bβ 1-42 was chromatographed on reverse-phase high performance liquid chromatography, two peaks of identical amino acid composition were separated, presumably due either to pyroglutamate or to amide differences.

Comprehensive Study of the Performance of Winter Tires on Ice, Snow, and Asphalt Roads: The Influence of Tire Type and Wear

2017 ◽  
Vol 45 (3) ◽  
pp. 175-199 ◽  
Author(s):  
Mattias Hjort ◽  
Olle Eriksson ◽  
Fredrik Bruzelius
Keyword(s):  
Vehicle Performance ◽  
Testing Facility ◽  
Recorded Data ◽  
Winter Road ◽  
Tire Testing ◽  
Tire Forces ◽  
Real Traffic ◽  
Real Vehicle ◽  
Comprehensive Study

ABSTRACT This work presents a comprehensive study of the performance of winter tires on snow, ice, and asphalt. A set of 77 different winter tires were carefully selected for the study. Of these, 27 were new and 50 were worn from real traffic use. All three tire types for winter conditions (Nordic, European, and studded) were represented. All tires have been tested using a mobile tire-testing device for snow and asphalt and using a stationary tire-testing facility for ice. Both devices recorded the tire forces and motions, enabling a close to complete stationary characterization of the tires. In addition, 42 of the tires were tested on a passenger car, where brake performance was evaluated for the three different road conditions. This enables a comparative study of performance between tire types and wear for various winter road conditions. The results suggest that the recorded data represent real vehicle performance. Some conclusions from the measurements are that the effect of wear is consistent between the tire groups and that the performance degradation is most noticeable on studded tires on ice and on European tires on snow.

Simultaneous Determination of Eight Potential Q-Markers in Zishen Tongguan Capsules Based on UHPLC-MS/MS

2020 ◽  
Vol 17 (1) ◽  
pp. 47-56
Author(s):  
Shun Liu ◽  
Xun Wang ◽  
Kaiping Zou ◽  
Wei Liu ◽  
Cunyu Li ◽  
...  
Keyword(s):  
Quality Control ◽  
Chinese Medicine ◽  
Simultaneous Determination ◽  
High Performance ◽  
Multiple Reaction Monitoring ◽  
Gradient Elution ◽  
Quality Markers ◽  
High Repeatability ◽  
Comprehensive Study

Background: Zishen Tongguan (ZSTG) capsules were prepared at the Affiliated Hospital of Nanjing University of Chinese Medicine and have been proven to be clinically effective for treating pyelonephritis and benign prostatic hyperplasia. However, the quality standards are not ideal; a comprehensive study of the “quality markers” (Q-markers), the chemicals inherent in traditional Chinese medicine and its preparations, has not been carried out. Experimental Methods: In this paper, a sensitive and specific ultra-high-performance liquid chromatographictandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of eight potential Q-markers of ZSTG, including timosaponin A3, berberine, jatrorrhizine, phellodendrine, palmatine, mangiferin, neomangiferin, and timosaponin BII. A Kromasil 100-3.5 C18 column was used with a mobile phase of 0.2% formic acid with acetonitrile, and gradient elution at a flow rate of 0.2 mL/min was achieved in 13 minutes and used for separation. Detection was performed in positive/negative mode with multiple reaction monitoring (MRM). Results: The analytical method was validated in terms of the sensitivity, linearity, accuracy, precision, repeatability, stability and recovery. The method established here was successfully applied to study the potential Q-markers in 8 batches of commercial samples, which demonstrated its use in improving the quality control of ZSTG. Conclusion: The developed method had high repeatability and accuracy and was suitable for the simultaneous analysis of multiple Q-markers, which may provide a new basis for the comprehensive assessment and overall quality control of ZSTG.

Characterization of Antibacterial-Producing Endophytic Fungi of Syzygiumpolyanthum Leaves

2020 ◽  
Vol 20 (4) ◽  
pp. 448-454
Author(s):  
Rahmita Burhamzah ◽  
Gemini Alam ◽  
Herlina Rante
Keyword(s):  
Molecular Characterization ◽  
Endophytic Fungi ◽  
Morphological Characterization ◽  
Test Method ◽  
Analysis Method ◽  
Nitrogen Base ◽  
Rdna Genes ◽  
Antibacterial Screening ◽  
Planting Method

Background: Endophytic fungi live in plants’ tissue and can produce the same bioactive compounds as its host plant produces. Syzygiumpolyanthum leaves have known to be one of the antibacterial compound producers. Aim and Objective: This study aimed to characterize morphologically, microscopically, and molecularly the antibacterial-producing endophytic fungi of Syzygiumpolyanthum leaves. Methods: The isolation of endophytic fungi was done by fragment planting method on PDA medium. The antibacterial screening was performed using the antagonistic test as the first screening followed by the disc diffusion test method. The morphological characterization was based on isolate’s mycelia color, growth pattern, margin, and surface texture of the colony, while the microscopic characterization was based on its hyphae characteristics. The molecular characterization of the isolate was done by nitrogen base sequence analysis method on nucleotide constituent of ITS rDNA genes of the isolate. Results: The results found that isolate DF1 has antibacterial activity against E.coli, S.aureus, P.acne, and P.aeruginosa, with the greatest inhibition at 10% concentration of broth fermentation extract on S.aureus with a diameter of inhibition of 13.77 mm. Conclusion: Based on macroscopic, microscopic, and molecular characterization, DF1 isolate is similar to Ceriporialacerate.

Preparation and Characterization of the High Molecular Weight [3H]Hyaluronic Acid

1992 ◽  
Vol 57 (10) ◽  
pp. 2151-2156 ◽  
Author(s):  
Peter Chabreček ◽  
Ladislav Šoltés ◽  
Hynek Hradec ◽  
Jiří Filip ◽  
Eduard Orviský
Keyword(s):  
Molecular Weight ◽  
Hyaluronic Acid ◽  
High Molecular Weight ◽  
Methyl Bromide ◽  
High Performance ◽  
Hydrogen Atoms ◽  
Isolation And Characterization ◽  
Labelling Procedure ◽  
Enzymatic Depolymerization

Two methods for the preparation of high molecular weight [3H]hyaluronic acid were investigated. In the first one, hydrogen atoms in the molecule were replaced by tritium. This isotopic substitution was performed in aqueous solution using Pd/CaCO3 as the catalyst. In the second method, the high molecular weight hyaluronic acid was alkylated with [3H]methyl bromide in liquid ammonia at a temperature of -33.5 °C. High-performance gel permeation chromatographic separation method was used for the isolation and characterization of the high molecular weight [3H]hyaluronic acid. Molecular weight parameters for the labelled biopolymers were Mw = 128 kDa, Mw/Mn = 1.88 (first method) and Mw = 268 kDa, Mw/Mn = 1.55 (second method). The high molecular weight [3H]hyaluronic acid having Mw = 268 kDa was degraded further by specific hyaluronidase. Products of the enzymatic depolymerization were observed to be identical for both, labelled and cold biopolymer. This finding indicates that the described labelling procedure using [3H]methyl bromide does not induce any major structural rearrangements in the molecule.

scholarly journals Isolation and Characterization of Antibacterial Carotane Sesquiterpenes from Artemisia argyi Associated Endophytic Trichoderma virens QA-8

Antibiotics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 213
Author(s):  
Xiao-Shan Shi ◽  
Yin-Ping Song ◽  
Ling-Hong Meng ◽  
Sui-Qun Yang ◽  
Dun-Jia Wang ◽  
...  
Keyword(s):  
Endophytic Fungus ◽  
Micrococcus Luteus ◽  
Crystallographic Analysis ◽  
Medicinal Herb ◽  
Trichoderma Virens ◽  
Isolation And Characterization ◽  
Artemisia Argyi ◽  
Detailed Interpretation ◽  
Fungal Kingdom

Carotane sesquiterpenes are commonly found in plants but are infrequently reported in the fungal kingdom. Chemical investigation of Trichoderma virens QA-8, an endophytic fungus associated with the inner root tissue of the grown medicinal herb Artemisia argyi H. Lév. and Vaniot, resulted in the isolation and characterization of five new carotane sesquiterpenes trichocarotins I–M (1–5), which have diverse substitution patterns, and seven known related analogues (6–12). The structures of these compounds were established on the basis of a detailed interpretation of their NMR and mass spectroscopic data, and the structures including the relative and absolute configurations of compounds 1–3, 5, 9, and 10 were confirmed by X-ray crystallographic analysis. In the antibacterial assays, all isolates exhibited potent activity against Escherichia coli EMBLC-1, with MIC values ranging from 0.5 to 32 µg/mL, while 7β-hydroxy CAF-603 (7) strongly inhibited Micrococcus luteus QDIO-3 (MIC = 0.5 µg/mL). Structure-activity relationships of these compounds were discussed. The results from this study demonstrate that the endophytic fungus T. virens QA-8 from the planted medicinal herb A. argyi is a rich source of antibacterial carotane sesquiterpenes, and some of them might be interesting for further study to be developed as novel antibacterial agents.

scholarly journals Development and characterization of Nb3Sn/Al2O3 superconducting multilayers for particle accelerators

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chris Sundahl ◽  
Junki Makita ◽  
Paul B. Welander ◽  
Yi-Feng Su ◽  
Fumitake Kametani ◽  
...  
Keyword(s):  
High Performance ◽  
High Energy ◽  
Particle Accelerators ◽  
Quality Factors ◽  
Critical Fields ◽  
Linear Accelerators ◽  
Cross Sectional ◽  
Low Field ◽  
Superconducting Radio Frequency

AbstractSuperconducting radio-frequency (SRF) resonator cavities provide extremely high quality factors > 1010 at 1–2 GHz and 2 K in large linear accelerators of high-energy particles. The maximum accelerating field of SRF cavities is limited by penetration of vortices into the superconductor. Present state-of-the-art Nb cavities can withstand up to 50 MV/m accelerating gradients and magnetic fields of 200–240 mT which destroy the low-dissipative Meissner state. Achieving higher accelerating gradients requires superconductors with higher thermodynamic critical fields, of which Nb3Sn has emerged as a leading material for the next generation accelerators. To overcome the problem of low vortex penetration field in Nb3Sn, it has been proposed to coat Nb cavities with thin film Nb3Sn multilayers with dielectric interlayers. Here, we report the growth and multi-technique characterization of stoichiometric Nb3Sn/Al2O3 multilayers with good superconducting and RF properties. We developed an adsorption-controlled growth process by co-sputtering Nb and Sn at high temperatures with a high overpressure of Sn. The cross-sectional scanning electron transmission microscope images show no interdiffusion between Al2O3 and Nb3Sn. Low-field RF measurements suggest that our multilayers have quality factor comparable with cavity-grade Nb at 4.2 K. These results provide a materials platform for the development and optimization of high-performance SIS multilayers which could overcome the intrinsic limits of the Nb cavity technology.

Sign in / Sign up

Export Citation Format

Share Document