ABSTRACT
AimSARS-CoV-2 has been detected in stool samples of COVID-19 patients, with potential implications for faecal-oral transmission. Compared to swab samples, the complexity of the stool matrix poses a challenge in the detection of the virus that has not yet been solved. The aim of this study was to establish a sensitive and reliable method for detecting SARS-CoV-2 in stool samples. MethodsStool samples from individuals free of SARS-CoV-2 were homogenised in saline buffer and spiked with a known titre of inactivated virus ranging from 50 to 750 viral particles per 100 mg stool. Debris was removed via centrifugation and supernatants were concentrated by ultrafiltration. RNA was then extracted from the concentrated material using a commercial kit and SARS-CoV-2 was detected via real-time reverse-transcription polymerase chain reaction (RT-qPCR) using the CDC primers and probes. ResultsThe RNA extraction procedure we used allowed the detection of SARS-CoV-2 via RT-qPCR in most of the stool samples tested. We could detect as few as 50 viral particles per 100 mg of stool. However, high variability was observed across samples at low viral titres. The primer set targeting the N1 region provided more reliable and precise results and for this primer set our method had a limit of detection of 1 viral particle per mg of stool. ConclusionsHere we describe a sensitive method for detecting SARS-CoV-2 in stool samples. This method can be used to establish the persistence of SARS-CoV-2 in stool and ensure the safety of clinical practices such as faecal microbiota transplant (FMT).
ABSTRACT
Akkermansia muciniphila, a symbiotic bacterium of the mucus layer, can utilize mucin as its sole carbon, nitrogen, and energy source. As an abundant resident in the intestinal tract of humans and animals, the probiotic effects of A. muciniphila including metabolic modulation, immune regulation and gut health protection, have been widely investigated. Various diseases such as metabolic syndromes and auto-immnue diseases have been reported to be associated with the disturbance of the abundance of A. muciniphila. In this review, we describe the biological characterization of A. muciniphia, the factors that influence its colonization of the intestinal tract; and discuss the current state of our knowledge on its role in host health and disease.
Subject(s)
Probiotics , Verrucomicrobia , Akkermansia , Animals , Humans , Intestines/microbiology , MucinsABSTRACT
The traditionally perceived function of nutrition includes supplying the consumer with the appropriate quantity and quality of substrates. As nutritional substrates, proteins are prone to spontaneously occurring non-enzymatic glycosylation (glycation) which can alter their molecular structure, making them highly bioactive. Glycated food proteins are able to modify the bacterial intestinal ecosystem, which is of great importance for the optimal usage of nutrients and maintenance of both intestinal homeostasis and balanced health status of the consumer. This study aimed to determine the impact of glycated pea proteins on the intestinal bacteria from a healthy human. The analyses were conducted with the use of experimental batch-type simulator models imitating human intestinal conditions. The glycated pea proteins affected the growth of gut commensal bacteria, particularly lactobacilli and bifidobacteria, whose levels increased significantly. There was a corresponding shift in the bacterial metabolites with increased levels of the short chain fatty acids (SCFAs); acetate, propionate lactate and butyrate. Intestinal bacteria were able to utilize these pea proteins thus indicating that the energy encrypted in glycated pea proteins, partially inaccessible for gastric enzymes, may be salvaged by gut microbiota. Such changes in microbial composition may beneficially impact the intestinal environment and exert a health-promoting effect in humans.