In situ characterisation of a microorganism surface by Raman microspectroscopy: the shell of Ascaris eggs

  title={In situ characterisation of a microorganism surface by Raman microspectroscopy: the shell of Ascaris eggs},
  author={Fabienne Quil{\`e}s and Jean-Yves Balandier and Sandrine Capizzi-Banas},
  journal={Analytical and Bioanalytical Chemistry},
Intestinal nematodes are very common human parasites and a single species, Ascaris lumbricoïdes, is estimated to infect a quarter of the world’s population. A sticky external layer covers their eggs. This work shows that Raman vibrational confocal spectroscopy is able to give information on the biochemical composition of the shell of Ascaris eggs. The biochemical localised characterisation of Ascaris eggs was performed directly on the eggs in their aqueous environment. The studied parasites… 

Quick incubation process to determine inactivation of Ascaris and Toxocara eggs.

It is found that, using an inactivation process at a temperature of 60 °C for 1 hour and incubation at 28 °C and 34 °C, the absence of division of the nucleus of eggs of species from two genera, Ascaris lumbricoides and Toxocara canis, showed them to be inactivated following only 48 hours of incubation.

Effect of reagents used during detection and quantification of Ascaris suum in environmental samples on egg viability

  • I. AmoahP. ReddyT. Stenström
  • Biology
    Water science and technology : a journal of the International Association on Water Pollution Research
  • 2017
The use of the selected reagents in the detection of Ascaris suum eggs was found to affect the viability of exposed eggs, especially during prolonged exposures, and it was recommended that eggs be exposed for ≤ 5 minutes, to reduce the risk of viability loss.

Comparative assessment of DNA extraction procedures for Ascaris spp. eggs.

DNA extraction kits that incorporate a bead-beating step as well as other mechanical eggshell disruption steps were superior in extracting DNA from Ascaris spp.

In situ raman spectral mapping study on the microscale fibers in blue coral (Heliopora coerulea) skeletons.

The possibility was raised of producing high resolution surface ocean phosphorus records on daily environmental variation via P/Ca variation cycles determined from Raman mapping data.

Viability of Ascaris and other helminth genera non larval eggs in different conditions of temperature, lime (pH) and humidity.

  • C. MayaM. OrtizB. Jiménez
  • Medicine, Biology
    Water science and technology : a journal of the International Association on Water Pollution Research
  • 2010
Results showed that there is a combination of conditions (temperature, pH and humidity) that is optimal for inactivation, and Ascaris, Toxocara and Taenia, in that order, were the most resistant, while the most sensitive were Trichuris and Hymenolepis.

Real-time detection and identification of nematode eggs genus and species through optical imaging

This study demonstrates that non-invasive real-time identification of eggs is possible based on their intrinsic fluorescence and investigates the autofluorescence properties of five species of nematode eggs and observes clear differences between genus and for the first time their species in sludge samples.

A sensitive and specific PCR assay for the detection of Baylisascaris schroederi eggs in giant panda feces.



Ultrastructure of eggs of Ascaris lumbricoides Linnaeus, 1758. I. Egg-shells.

Under the light microscope the chitin-protein layer of egg-shells in ascarids appears to be a regular, hyaline and nonstructural layer of 1.5 to 2.00 microns in thickness, which shows a distinct lamellate structure only after a prolonged fixation with osmium at higher temperature.

Visualization of chitin-protein layer formation in Ascaris lumbricoides egg-shells.

Intensive formation of chitin structures in A. lumbricoides egg-shell occurred only in fertilized females in a very short portion of uterus from the site of connection of the oviduct with the uterus up to 25-30 mm distally, i.e. in the section forming about one fifth or less than one sixth of length of adult female uterus.

Multidimensional information on the chemical composition of single bacterial cells by confocal Raman microspectroscopy.

The multidimensional information in Raman spectra gives a global view on all major components of the cell at once, complementing other more specific information-rich methods for single-cell analysis and can be used, for example, to study heterogeneities in a microbial population.

Raman microscopic analysis of single microbial cells.

The utility of the Raman confocal microscope to generate a spectral profile from a single microbial cell and the use of this approach to differentiate bacterial species are demonstrated and suggest that Raman microscopy has significant potential for studies requiring the taxonomic identity and functioning of single microbial cells to be determined.

Embryonic and post-embryonic changes in the lipids of Ascaris lumbricoides eggs.

  • D. Fairbairn
  • Biology
    Canadian journal of biochemistry and physiology
  • 1955
Unembryonated ascaris eggs contained amounts of saponifiable and unsaponifiable lipids estimated to exceed 50% of the protoplasmic solids, and death of the embryos coincided with failure to utilize the remaining saponifiables.

Ascaris and ascariasis.

  • D. Crompton
  • Medicine, Biology
    Advances in parasitology
  • 2001

Structure of the ascarosides from Ascaris suum.

Six glycosides have been identified from the nematode Ascaris suum, and although 6 and 7 are related to ascaroside A, previously isolated from P. equorum, these earlier reports suggest the chain in ascarOSide A to be unbranched.

Structural analysis of heparin by raman spectroscopy.

The usefulness of Raman spectroscopy is extended to include structural details required for the quality assurance of pharmaceutical preparations of heparin to determine the relative proportion of the N-sulfate, 6-O-solfate, and 2-O'sulfate groups in theheparin molecule.