Potato proteins contain protease inhibitors, which suppress almost the complete proteolytic activity in faeces. Topical application of potato protease inhibitors might be a novel approach in preventing protease-induced peri-anal dermatitis, and therapeutic studies are needed to confirm our results.

Microbiota-accessible carbohydrates (MACs) are powerful modulators of microbiota composition and function. These substrates are often derived from diet, such as complex polysaccharides from plants or human milk oligosaccharides (HMOs) during breastfeeding. Host-derived mucus glycans on gut-secreted mucin proteins serve as a continuous endogenous source of MACs for resident microbes; here we investigate the potential role of purified, orally administered mucus glycans in maintaining a healthy microbial community. In this study, we liberated and purified O-linked glycans from porcine gastric mucin and assessed their efficacy in shaping the recovery of a perturbed microbiota in a mouse model. We found that porcine mucin glycans (PMGs) and HMOs enrich for taxonomically similar resident microbes. We demonstrate that PMGs aid recovery of the microbiota after antibiotic treatment, suppress Clostridium difficile abundance, delay the onset of diet-induced obesity, and increase the relative abundance of resident Akkermansia muciniphila. In silico analysis revealed that genes associated with mucus utilization are abundant and diverse in prevalent gut commensals and rare in enteric pathogens, consistent with these glycan-degrading capabilities being selected for during host development and throughout the evolution of the host–microbe relationship. Importantly, we identify mucus glycans as a novel class of prebiotic compounds that can be used to mitigate perturbations to the microbiota and provide benefits to host physiology.

In this prospective cohort study, we examine the feasibility of a protocol to optimize microbiota for fecal microbiota transplantation (FMT). Donor stool metrics generally accepted as markers of gut health were used to select a stool donor based on superior microbial diversity, balanced constitution of Bacteroidetes versus Firmicutes and high concentration of fecal butyrate. Selected donor microbiota was then administered via FMT. A total of 10 patients with median age of 12 years with recurrent Clostridium difficile infection received the intervention. The rate of recurrence-free resolution with 1-2 FMTs was 100% at Week 10. With a single FMT, 80% of patients cleared Clostridium difficile infection without recurrence, whereas 20% of patients required a single re-treatment. No serious adverse events occurred. Microbiota sequencing revealed that recipients' gut microbiota phylogenic diversity increased by 72-hours post-transplantation, with sustainment over 10-week follow-up. This study highlights the feasibility of purposefully selecting the most ideal microbiota for transplantation.

1 Microbiota-accessible carbohydrates (MACs) are powerful modulators of microbiota 2 composition and function. These substrates are often derived from diet, such as complex 3 polysaccharides from plants or human milk oligosaccharides (HMOs) during breastfeeding.4Host-derived mucus glycans on gut-secreted mucin proteins may serve as a continuous 5 endogenous source of MACs for resident microbes; here we investigate the potential role of 6 purified, orally-administered mucus glycans in maintaining a healthy microbial community. In 7 this study, we liberated and purified O-linked glycans from porcine gastric mucin and assessed 8 their efficacy in shaping the recovery of a perturbed microbiota in a mouse model. We found that 9 porcine mucin glycans (PMGs) and HMOs enrich for taxonomically similar resident microbes.