The double-blinded randomised controlled trial (RCT) examined the effect of a proprietary strain of deactivated Bacillus subtilis (BG01-4) high in branched-chain fatty acids (BCFA) to treat self-reported FGID versus placebo in 67 participants over four weeks.
The authors from Australia and the US conclude: “Consumption of BG01-4 was well tolerated and resulted in relief of symptoms of constipation and related GI dysfunction.
“Significant improvements in overall GSRS suggest that BG01-4 has a potential role in relieving specific symptoms of dyspepsia, indigestion, and constipation.”
FGIDs are a heterogeneous group of chronic conditions characterised by persistent and recurrent gastrointestinal symptoms without any apparent structural or biochemical abnormalities, affecting between 25 and 40% of the global population.
Over two-thirds of people with FGID have reportedly sought medical advice from a doctor, with 40% having been prescribed regular medication, and around a third undergoing potentially unnecessary abdominal surgery for their symptoms.
The most common FGID conditions include functional bowel disorders and irritable bowel syndrome, as well as functional constipation, functional diarrhoea, and functional bloating.
Dietary restriction is a well-established therapy for some types of FGID, however, a previous study found that one-third of adults with a gastrointestinal condition were restricting their diet, which affected their mental health and overall quality of life.
Branched-chain fatty acids (BCFAs) were first recognised as nutrients important to gastrointestinal (GI) health in the context of vernix caseosa, the white waxy substance that develops on late-term human foetuses.
Bacillus subtilis (B. subtilis), the most well-studied gram-positive microorganism, reportedly has an excess of 50% of BCFAs in its membrane lipids.
The researchers behind the current study screened numerous B. subtilis strains cultured at lab scale (unpublished), to identify a particularly fast-growing strain with high levels of BCFAs, designated “BG01-4.”
BG01-4 was derived by fermentation, deactivated, and freeze dried. The authors prepared spores (5 × 109 colony-forming units) of deactivated B. subtilis BG01-4 into a powdered form in sachets that can be mixed into drinks or foods and consumed as a probiotic.
B. subtilis has previously been shown to promote improvements in those with constipation and diarrhoea, and reduced the frequency and severity of abdominal bloating.
However, the authors note that well-designed RCTs investigating B. subtilis efficacy on overall quality of life in people with FGID have not previously been undertaken.
The current study included healthy adults (n = 67) between 18 and 75 years of age (all: 49.9 ± 14.1 years; males: n = 25 53.5 ± 12.9 years; females n = 42 48.8 ± 14.2 years).
Inclusion for participation involved meeting criteria included a self-diagnosis of symptoms including recurrent abdominal bloating, loose or watery stools, and / or functional constipation, that must have begun at least 6 months prior and for at least 3 months.
Participants completed an intervention of BG01-4 (n = 34) or placebo (n = 33), consuming one sachet per day for four weeks.
A Gastrointestinal Symptom Rating Scale (GSRS) survey was conducted prior to, at two weeks, and at four weeks after completion of the intervention.
Resulting data indicated that at four weeks, constipation in the experimental group was improved by 33% compared to placebo (15%).
Total GSRS and diarrhoea were significantly improved in both the experimental and placebo groups (32%/26% and 20%/22%, respectively).
Indigestion was improved at four weeks (32%) but compared to the placebo (21%) was not significant (p = 0.079).
Exploratory analysis, however, revealed that clusters for constipation (18% improvement, p < 0.001), indigestion (11% improvement, p = 0.04), and dyspepsia (10% improvement, p = 0.04) were significantly improved in the intervention group compared to the placebo.
The authors do however note that the study was limited due to the invention period, as some probiotic studies report that an intervention of at least 60 days is useful for statistical significance, and others suggest that this period is not long enough to see the full effects on gastrointestinal disorders.
The authors conclude: “Longer-term confirmatory studies for this intervention are warranted.”
Bacillus Subtilis (BG01-4TM) Improves Self-Reported Symptoms for Constipation, Indigestion, and Dyspepsia: A Phase 1/2A Randomized Controlled Trial
Authors: Craig Patch, Alan J. Pearce, Mek Cheng, Ray Boyapati, and J. Thomas Brenna