Isolation and Characterization of Minor Analogues of Silvestrol and Other Constituents from a Large-Scale Re-collection ofAglaia foveolata

In Vietnam and around the world, Staphylococcus aureus remains a major hazard of food safety and food poisoning. S. aureus is present in many places and easily contaminates food production during processing chains. In this study, we successfully isolated S. aureus strains from suspected samples of two food borne poisoning outbreaks in Ha Giang and Vinh Phuc in 2017 and 2018, respectively. The collected samples were examined for presence of staphylococcal enterotoxins (SEs) by using 3MTMTECRATM Staph Enterotoxin kit, from there all the samples were positive with SEs. Different strains of S. aureus were isolated and then confirmed by MALDI-TOF technique. Those strains then were stored in Brain heart solution with 15% glycerol until further analysis. Our results identified three STs, ST96, ST88 (spa type t7558), and ST72 (spa type t3092), were responsible for two outbreaks. Two virulence genes detected from the above strains were sea and sec. Furthermore, these strains are test for antibiotic resistance susceptibility with commonly antibiotics. Penicillin are found to be resisted by all three STs, in particularly, ST96 and ST88 are both resistant to erythromycin while ST72 is resistant to gentamicin. Taken together, our study highlights the usefulness of molecular characterization to study and monitor bacterial pathogens associated with food poisoning outbreaks in Vietnam.

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ISOLATION AND CHARACTERIZATION OF NEUROSPORA MUTANTS AFFECTED IN INVERTASE SYNTHESIS

Genetics ◽

10.1093/genetics/106.4.591 ◽

1984 ◽

Vol 106 (4) ◽

pp. 591-599

Author(s):

Deborah B Lee ◽

Stephen J Free

Keyword(s):

Neurospora Crassa ◽

Large Scale ◽

Invertase Activity ◽

Free Medium ◽

Wild Type ◽

Isolation And Characterization ◽

Normal Enzyme ◽

Enzyme Molecules ◽

Large Scale Screening

ABSTRACT We have outlined a procedure that allows the large-scale screening of mutagenized Neurospora crassa populations for invertaseless mutants. We have isolated and characterized three mutations, inv(DBL1), inv(DBL9) and inv(DBL14), which have been mapped at or near the invertase structural gene. One of these, inv(DBL1), is particularly interesting. Our experiments indicate that the reduced level of invertase activity in the inv(DBL1)-containing cell can be explained as the result of a reduced number of normal enzyme molecules. We also show that wild-type Neurospora is able to respond rapidly to a change of medium and can dramatically increase its production of invertase within 20 min after a transfer to a carbon-free medium.

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A large-scale systematic survey of SARS-CoV-2 antibodies reveals recurring molecular features

10.1101/2021.11.26.470157 ◽

2021 ◽

Author(s):

Yiquan Wang ◽

Meng Yuan ◽

Jian Peng ◽

Ian A. Wilson ◽

Nicholas C. Wu

Keyword(s):

Large Scale ◽

Somatic Hypermutation ◽

Antigen Specificity ◽

Human Antibodies ◽

The Past ◽

Influenza Hemagglutinin ◽

Molecular Features ◽

Isolation And Characterization ◽

Single Antigen

In the past two years, the global research in combating COVID-19 pandemic has led to isolation and characterization of numerous human antibodies to the SARS-CoV-2 spike. This enormous collection of antibodies provides an unprecedented opportunity to study the antibody response to a single antigen. Using information derived from 88 research publications and 13 patents, we have assembled a dataset of ~8,000 human antibodies to the SARS-CoV-2 spike from >200 donors. Analysis of antibodies that target different domains of the spike protein reveals a number of common (public) responses to SARS-CoV-2, exemplified via recurring IGHV/IGK(L)V pairs, CDR H3 sequences, IGHD usage, and somatic hypermutation. We further present a proof-of-concept for predicting antigen specificity by using deep learning to differentiate sequences of antibodies to SARS-CoV-2 spike and to influenza hemagglutinin. Overall, this study not only provides an informative resource for antibody research, but fundamentally advances our molecular understanding of public antibody responses.

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Isolation and Characterization of 1-Tigloyl-3-acetylazadirachtol from the Seed Kernels of the Thai Neem Azadirachta siamensis Valeton

Zeitschrift für Naturforschung B ◽

10.1515/znb-1997-1120 ◽

1997 ◽

Vol 52 (11) ◽

pp. 1413-1417 ◽

Cited By ~ 3

Author(s):

H.-O. Kalinowski ◽

C. Krack ◽

K. Ermel ◽

C. Chriathamjaree

Keyword(s):

Large Scale ◽

Botanical Insecticides ◽

Preparative Hplc ◽

Isolation And Characterization ◽

Liquid Liquid Extraction ◽

Related Compounds ◽

Analytical Hplc ◽

Azadirachtin A ◽

C Nmr

Abstract The Thai neem A. siamensis (Valeton) is the main source for botanical insecticides in Thailand. Although azadirachtin A (aza A) is present in Thai neem, there are some other related compounds which may contribute to its bioefficiency. Analytical HPLC of Thai neem samples showed a peak closely eluted with azadirachtin. A large-scale cleanup involving two liquid/liquid extraction steps, silica filtration, and finally two successive preparative HPLC separations, resulted in the pure compound, which was identified as 1-tigloyl-3-acetylazadirachtol by 1D -and 2D -1H and 13C NMR spectroscopy.

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Cluster/Surface Interactions and Cluster/Matrix Deposition

MRS Proceedings ◽

10.1557/proc-206-363 ◽

1990 ◽

Vol 206 ◽

Cited By ~ 1

Author(s):

Mark M. Ross ◽

John H. Callahan ◽

Fred L. King ◽

Vicki H. Wysocki ◽

Stephan B.H. Bach ◽

...

Keyword(s):

Large Scale ◽

Cluster Ions ◽

Recent Measurement ◽

Naval Research ◽

Scale Production ◽

Mass Spectrometers ◽

Matrix Deposition ◽

General Utility ◽

Isolation And Characterization

ABSTRACTThis paper reports the most recent results from the cluster chemistry program at the Naval Research Laboratory, in which our efforts in the characterization of gas-phase cluster properties have been extended to studies of condensed-phase species. First, in an attempt to investigate the fundamental interactions between mass-selected cluster ions and surfaces, two tandem mass spectrometers were constructed or modified, and the results of the initial experiments will be discussed. The emphasis will be on illustrating the general utility of ion/surface collisions to study fragmentations, reactions, and deposition. Second, clusters were deposited into a matrix in order to perform spectroscopic analyses. The initial experiments have been directed at optimization of the techniques. Finally, recent measurement of the ionization potentials of large carbon clusters will be reported. These results are especially significant because of the new developments in large-scale production, isolation, and characterization of these species.

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Isolation and Characterization of PHA Producing Bacteria from Sewage Samples of Assam

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d4287.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 10686-10692

Keyword(s):

Large Scale ◽

Raw Materials ◽

Bacterial Species ◽

Scale Production ◽

High Turnover ◽

Isolation And Characterization ◽

Naturally Occurring ◽

Large Scale Production ◽

The Individual

Polyhydroxyalkanoate (Pha) Is A Family Of Naturally Occurring Polymers Which Is Reportedly Produced By More Than 75 Genera Of Gram-Positive And Gram-Negative Bacteria. Although The Industrial Production Of This Bioplastic Commenced Decades Ago, Its Large Scale Production Is Still Debilitated By Factors Such As Rate Of Production By The Bacteria And The Raw Materials For Its Production, Which Finally Elevates The Production Cost. The Present Thrust In This Area Is To Isolate Bacterial Species Which Have A High Turnover Of Pha With Minor Expenditure. Sewage And Sewage Sludge Samples Are Rich Sources Of Microflora Which Offer A Nutrient Limited Habitat To The Individual Organisms. Under These Conditions Of Stress, Native Organisms Develop A Metabolomics Which Efficiently Convert Vital Nutrients Into Essential Macromolecules, And In This Case A Storage Polymer Of Industrial Significance I.E. Pha. In This Pilot Study An Attempt Was Made To Isolate Indigenous Bacterial With Ability To Produce The Polymer.

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