Experimental use of a new surface acoustic wave sensor for the rapid identification of bacteria and yeasts

Casalinuovo, I. A.; Pierro, Donato Di; Bruno, Ernesto; Francesco, Paolo Di; Coletta, Massimo

doi:10.1111/j.1472-765x.2005.01792.x

Cited by 23 publications

(16 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fermentation will, of course, change the character of the durian aroma. A zNose TM (ultrafast gas chromatograph) was used to profile the generation of aroma compounds during fermentation of durian pulp as earlier studies have successfully demonstrated the zNose TM application in analysis of bacterial (Casalinuovo et al 2006), honey (Lammertyn et al 2004) and lilac flower Oh et al (2008). In this study, the instrument was used in a qualitative manner to profile aroma changes that took place during fermentation of durian pulp.…”

Section: Resultsmentioning

confidence: 99%

Effect of temperature-controlled fermentation on physico-chemical properties and lactic acid bacterial count of durian (Durio zibethinus Murr.) pulp

2012

View full text Add to dashboard Cite

Effects of controlled-temperature fermentation on several physico-chemical properties, lactic acid bacteria (LAB) counts and aroma of durian pulp were examined by storing fresh durian pulp was mixed with 2 % (w/w) salt and stored at 15°C, 27°C and 40°C for 10 days. Storage at 15°C did not affect the properties of the pulp much. However, at 27°C and 40°C, pH and total soluble solids decreased up to 60 % and 52 %, respectively, with greater losses at 27°C. Titratable acidity, which increased at 27°C, was due to lactic and acetic acids formation. Loss of sucrose and increases in glucose were greater at 27°C. LAB population increased up to Day 3 of storage, and then decreased slightly. Principal component analysis based on aroma examination using a zNose TM showed better retention of aroma profile at 27°C. Overall, durian fermented at 27°C was more acceptable than the one prepared at 40°C, and it is ready to be consumed between Day 4 and 6.

show abstract

Section: Resultsmentioning

confidence: 99%

Effect of temperature-controlled fermentation on physico-chemical properties and lactic acid bacterial count of durian (Durio zibethinus Murr.) pulp

2012

View full text Add to dashboard Cite

show abstract

“…Technical difficulties also arise from the variety and size of the compounds to be investigated, which range from organic compounds to simple gases. Whereas the zNose may be used for real time detection of VOC production from bacterial cultures (Casalinuovo et al ., ; Dawson et al ., ), concurrent measurement of gases such as ammonia will require sophisticated analytical instrumentation not readily available to microbiology laboratories. SIFT‐MS and GC‐MS are large expensive instruments well suited to these types of analysis.…”

Section: Discussionmentioning

confidence: 98%

Production of volatile organic compounds by mycobacteria

McNerney

Mallard

Okolo

et al. 2012

FEMS Microbiol Lett

View full text Add to dashboard Cite

The need for improved rapid diagnostic tests for tuberculosis disease has prompted interest in the volatile organic compounds (VOCs) emitted by Mycobacterium tuberculosis complex bacteria. We have investigated VOCs emitted by Mycobacterium bovis BCG grown on Lowenstein-Jensen media using selected ion flow tube mass spectrometry and thermal desorption-gas chromatography-mass spectrometry. Compounds observed included dimethyl sulphide, 3-methyl-1-butanol, 2-methyl-1-propanol, butanone, 2-methyl-1-butanol, methyl 2-methylbutanoate, 2-phenylethanol and hydrogen sulphide. Changes in levels of acetaldehyde, methanol and ammonia were also observed. The compounds identified are not unique to M. bovis BCG, and further studies are needed to validate their diagnostic value. Investigations using an ultra-rapid gas chromatograph with a surface acoustic wave sensor (zNose) demonstrated the presence of 2-phenylethanol (PEA) in the headspace of cultures of M. bovis BCG and Mycobacterium smegmatis, when grown on Lowenstein-Jensen supplemented with glycerol. PEA is a reversible inhibitor of DNA synthesis. It is used during selective isolation of gram-positive bacteria and may also be used to inhibit mycobacterial growth. PEA production was observed to be dependent on growth of mycobacteria. Further study is required to elucidate the metabolic pathways involved and assess whether this compound is produced during in vivo growth of mycobacteria.

show abstract

“…Differential speciation of micro-organisms present in primary cultures of clinical samples could be performed by real-time identification of volatile organic compounds (VOCs) produced during microbial replication. Classical culture has been combined with such olfactory measurements in the past [ 4 ]. It needs to be emphasised that these experiments always involved cultivation endpoint measurements.…”

Section: Introductionmentioning

confidence: 99%

Device-independent, real-time identification of bacterial pathogens with a metal oxide-based olfactory sensor

Bruins

Bos²,

Petit

et al. 2009

Eur J Clin Microbiol Infect Dis

View full text Add to dashboard Cite

A novel olfactory method for bacterial species identification using an electronic nose device called the MonoNose was developed. Differential speciation of microorganisms present in primary cultures of clinical samples could be performed by real-time identification of volatile organic compounds (VOCs) produced during microbial replication. Kinetic measurements show that the dynamic changes in headspace gas composition are orders of magnitude larger than the static differences at the end of fermentation. Eleven different, clinically relevant bacterial species were included in this study. For each of the species, two to eight different strains were used to take intra-species biodiversity into account. A total of 52 different strains were measured in an incubator at 37°C. The results show that the diagnostic specificities varied from 100% for Clostridium difficile to 67% for Enterobacter cloacae with an overall average of 87%. Pathogen identification with a MonoNose can be achieved within 6-8 h of inoculation of the culture broths. The diagnostic specificity can be improved by broth modification to improve the VOC production of the pathogens involved.

show abstract

Experimental use of a new surface acoustic wave sensor for the rapid identification of bacteria and yeasts

Cited by 23 publications

References 31 publications

Effect of temperature-controlled fermentation on physico-chemical properties and lactic acid bacterial count of durian (Durio zibethinus Murr.) pulp

Effect of temperature-controlled fermentation on physico-chemical properties and lactic acid bacterial count of durian (Durio zibethinus Murr.) pulp

Production of volatile organic compounds by mycobacteria

Device-independent, real-time identification of bacterial pathogens with a metal oxide-based olfactory sensor

Contact Info

Product

Resources

About