Effects of targeted colonic symbiotic supplementation with Bacillus subtilis DSM 32315 and L-alanyl-L-glutamine on mental wellbeing: An open-label pilot study

Abstract

The gut-brain axis plays a pivotal role in mental health, with synbiotic supplements emerging as promising interventions for stress and anxiety management. This observational open-label pilot study aims to evaluate the effects of a symbiotic supplement containing Bacillus subtilis DSM 32315 and L-alanyl-L-glutamine, delivered via a targeted colonic-release capsule, on stress, anxiety, and mental wellbeing. Conducted as a non-placebo-controlled real-world case study, the study recruited 100 adults with elevated perceived stress and followed them for over eight weeks. Validated self-reporting tools, including the Depression Anxiety Stress Scales-21 items (DASS-21), Perceived Stress Scale-10 items (PSS-10), Athens Insomnia Scale (AIS), Short Form Health Survey-12 items, and Gastrointestinal Symptom Rating Scale questionnaires, were used to assess outcomes. Statistical analyses, primarily using linear mixed models, indicated reductions in DASS-21, PSS-10, and AIS scores, along with self-reported improvements in gastrointestinal symptoms and mental well-being. These findings should be interpreted cautiously due to the exploratory, uncontrolled study design. Notably, DASS-21 total scores declined within one week, with reported benefits sustained at four and eight weeks. However, these rapid changes may partly reflect expectancy effects or regression to the mean. These observations provide valuable insights for further hypothesis generation, notably that the synbiotic supplement could support stress management and mental health by modulating the gut-brain axis. However, further placebo-controlled trials including measurement of relevant biomarkers are warranted to confirm these observations and explore underlying mechanisms.

Keywords

Synbiotic / Bacillus subtilis / L-alanyl-L-glutamine / Colonic delivery / Gut-brain axis / Mental well-being / Short-chain fatty acids / Real-world study

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