Table 4.
Potential electronic-nose applications for human and animal disease diagnoses via detection of volatile biomarker indicator compounds produced by bacterial pathogens that are causal agents of specific diseases.
| Pathogenic agent | Disease | Aroma sample source | Potential biomarkers | References |
|---|---|---|---|---|
| Campylobacter jejuni | Gastroenteritis | Feces | Hexanal, (E)-2-octenal, pyrrole, ethyl ethanoate, methyl alcohol, 2-heptanone | [74] |
| Clostridium septicum | Intestinal disease | Culture from intestine | Isobutylamine, isopentylamine, ethylamine | [11] |
| Enterococcus faecalis | Gastroesophageal disease | Complex broth cultures | Terpenes, trimethylamine, ketones | [244] |
| Escherichia coli | Gastrointestinal diseases | Complex broth cultures | Terpenes, trimethylamine, ketones; ethanol | [244,320] |
| Helicobacter pylori | Stomach ulcers | Gastroesophageal cultures | Terpenes, trimethylamine, ketones | [244] |
| Klebsiella pneumoniae | Gastrointestinal diseases | Urine | Trimethylamine, ethyl acetate | [9] |
| Mycobacterium tuberculosis | Tuberculosis | Human sputum cultures | Specific complex mixture of VOCs | [17,27,302,321] |
| Proteus mirabilis | Urinary tract infections | Urine | Benzaldehyde, isobutyraldehyde, isovalaraldehyde; sulfides | [301,316] |
| Urinary tract infections | Urine | Dimethyl sulphide, methyl mercaptan | [301] | |
| Urinary tract infections | Urine | Trimethylamine, ethyl acetate | [9] | |
| Urinary tract infections | Urine | Isobutanol, isopentyl acetate ketones, I-undecene | [287,317] | |
| Pseudomonas aeuroginosa | Localized infections | Skin, lung | Butanol, methyl ketones (2- 2-nonanone, 2-undecanone), heptanone, 2-aminoaceto-phenone | [311,314,317] |
| Pseudomonas perolens, P. taetrolens | Food poisoning (eggs etc.) | Stomach | 2-methoxy-3-isopropylpyrazine (MIPP) | [312,313] |
| Staphalococcus aureus | Localized & systemic infections | All parts of the body | Isobutanol, isopentyl acetate ketones, I-undecene | [318] |
| Vibrio cholerae | Cholera | Feces | p-menth-1-en-8-ol, dimethyl disulphide | [74] |
†
Bio-indicator compounds are volatile organic compounds (VOCs) that usually were initially identified and confirmed using gas chromatography-mass spectroscopy (GC-MS) or similar analytical equipment prior to development of corresponding e-nose reference libraries for detection.