Evaluation of gut bacterial populations using an electronic e-nose and field asymmetric ion mobility spectrometry: further insights into ‘fermentonomics’

Abstract

The fermentation of undigested foods in the large bowel, by its resident bacteria, results in the production of several chemicals including volatile gases. Perturbance in gut bacteria is known to influence colonic and metabolic health, but to determine this requires prolonged culture (often unsuccessful) or expensive genomic sequencing. Clearly this is not practical for daily clinical practice. Previously, we have reported our insights into fermentonomics through the detection of volatile organic compounds (VOCs) in patients with gastrointestinal and metabolic diseases, using the electronic nose. In this paper we report on the changes in the fermentone produced by patients undergoing complete versus partial bowel cleansing. Using urine samples, preliminary results from 23 individuals receiving bowel cleansing indicate the ability of the electronic nose to distinguish between the partial and complete procedures. Moreover in a subset of individuals, we have been able to track evolving bacterial recolonization over time using the e-nose and field asymmetric ion mobility spectrometry (FAIMS). Such an approach has practical application in tracking bacterial dysbiosis following perturbation.

Application and Uses of Electronic Noses for Clinical Diagnosis on Urine Samples: A Review

“…The following sections provide an overview of the state-of-the-art of the application of electronic noses for the analysis of urine samples by classifying those applications depending on the target investigated, thus including the discrimination of bacteria cultures (Section 2.2) [49,50,51,52], or the detection of urinary tract infections (Section 2.3) [53,54,55,56,57,58], cancer diseases (Section 2.4) [59,60,61,62,63,64,65,66], diabetes (Section 2.5) [67,68], kidney diseases (Section 2.6) [69,74], bowel diseases (Section 2.7) [70,71,72] and exposure to toxic agents (Section 2.8) [73] (reference [74] wasn’t included in Table 1 since it refers to breath analysis).…”

“…Arasaradnam et al [70] proposed to analyse this components using non-invasive tools, such as an electronic nose and a Field Asymmetric Ion Mobility Spectrometer (FAIMS). FAIMS is a newer technology that separates ionized molecules based on their different mobility in a high electric field.…”

Review article: next generation diagnostic modalities in gastroenterology – gas phase volatile compound biomarker detection

“…Electronic nose technology was able to distinguish between individuals who had complete compared with partial bowel preparation. Moreover in a subset of individuals, electronic nose was able to identify evolving bacterial re‐colonisation over time – offering a practical non‐invasive approach to track bacterial dysbiosis following iatrogenic or idiopathic perturbation …”

Non-Invasive Distinction of Non-Alcoholic Fatty Liver Disease using Urinary Volatile Organic Compound Analysis: Early Results

“…This would indicate that they represent the complex interaction of colonocytes, human gut microflora and invading pathogens [26]. The resultant products of fermentation, 'the fermentome' can exist in the gaseous phase and are present in exhaled air, sweat, urine and faeces [23,25,[27][28][29]. Their presence in bodily secretions from sites other than the gastrointestinal tract (sweat, exhaled air and urine) is presumed possible due to the altered gut permeability afforded in certain disease states [27].…”