Sericin-derived oligopeptides (SDOs) up to **1.8 g/day** are safe, well-tolerated, and maintain gut microbiota.
Background
Despite the strong bioactive properties of Sericin-derived oligopeptides (SDOs) from Bombyx mori yellow silk cocoons, clinical safety data is crucial for regulatory approval as a novel food ingredient. Specifically, SDOs produced by enzymatic hydrolysis, rich in serine (20.5%) and aspartic acid (16.9%), require human safety validation. This study addresses this gap by evaluating the short-term safety, tolerability, and impact on gut microbiota in healthy individuals, laying the groundwork for broader applications of this unique peptide composition.
Study Design
This Phase 0 randomized, double-blind, placebo-controlled trial enrolled 42 healthy adult volunteers, who were randomized (1:1:1) to receive daily doses of placebo, 0.9 g SDOs, or 1.8 g SDOs for eight weeks. Primary safety endpoints included vital signs, hematology, and comprehensive clinical chemistry (renal and hepatic functions). Secondary outcomes assessed lipid profiles, oxidative stress markers (hs-CRP, TAC, SOD, MDA), and gut microbiota composition, which was analyzed using 16S rRNA metagenome sequencing to understand microbial changes.
Results
The study demonstrated a favorable safety profile for SDOs, with 41 participants (97.6%) completing the trial with high compliance (>98%). No serious adverse events were reported across any group. All primary clinical parameters, including vital signs, hematology, and renal/hepatic functions, remained within clinically normal ranges, showing no significant differences between groups throughout the study (p > 0.05). Importantly, SDOs supplementation had no adverse effects on fasting blood glucose, lipid profiles, or systemic oxidative stress markers. The 16S rRNA sequencing analysis confirmed that SDOs maintained gut microbial homeostasis over the 8-week intervention, with Bacteroidetes and Firmicutes consistently identified as the predominant phyla in the core community structure. Oral intake of enzymatically generated SDOs up to 1.8 g/day was well-tolerated, with only occasional mild and transient gastrointestinal symptoms that were not dose-dependent.
Oral Sericin-derived oligopeptides (SDOs) up to 1.8 g/day in healthy adults were well-tolerated, with no significant adverse effects on clinical parameters or gut microbiota composition.
Key Findings
- Oral SDOs up to 1.8 g/day were well-tolerated in healthy adults over 8 weeks.
- No serious adverse events were reported across any SDOs dose group.
- Primary clinical safety parameters (vital signs, hematology, renal/hepatic function) remained normal (p > 0.05).
- SDOs maintained gut microbial homeostasis, with
BacteroidetesandFirmicutesremaining predominant. - No adverse effects on lipid profiles, fasting blood glucose, or oxidative stress markers were observed.
Why It Matters
This study provides the first clinical safety and tolerability data for this specific Sericin-derived oligopeptide composition, which is critical for its potential regulatory approval as a novel food ingredient. For peptide users and biohackers, these findings suggest that SDOs are a safe and well-tolerated supplement for general health and gut support, particularly at doses up to 1.8 g/day. This opens the door for further research into its bioactive properties beyond safety, such as its potential immunomodulatory or anti-aging effects, without immediate concerns about short-term adverse events. While these are preliminary findings in healthy adults, they establish a foundational safety profile, making SDOs a promising candidate for future functional food and supplement development.
sericin-derived-oligopeptides
sdos
safety
tolerability
gut-microbiota
healthy-adults