Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1: What Is It, Cosmetic Uses, Benefits & Side Effects

Curious about this ingredient? In this article we're explaining exactly what it is and why it's used within cosmetic formulations.
Updated on: June 30, 2025
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We verify all information on this page using publicly available nomenclature standards from The Personal Care Products Council (PCPC), the European Commission's CosIng database and documentation provided directly by ingredient manufacturers. Our analysis is based on technical data from these sources to ensure accuracy and reliability.

What Is Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1?

Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1 is a lab made peptide that blends two naturally occurring protein fragments, one from rainbow trout and one that copies a human cell signaling protein. Scientists piece the two genes together then let friendly strains of E. coli grow the peptide in large stainless-steel tanks. After fermentation the peptide is separated, purified and gently dried to make a stable powder for cosmetics.

The finished molecule holds 160 amino acids arranged in the same order found in living tissue. It can also form tiny bridges called disulfide bonds and pick up sugar groups during processing which help it fold correctly and stay active on skin and hair.

Fish-derived peptides first drew interest in the 1990s when researchers noticed they could calm irritation and support repair of damaged skin. As biotech tools improved brands looked for sustainable ways to produce these peptides without overfishing. Fermentation in microbes solved the supply issue and opened the door for use in everyday beauty products.

Today you will spot Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1 in lightweight anti-aging serums, rich moisturizers, soothing sheet masks, leave-on hair conditioners and scalp treatments that aim to keep strands strong and shiny.

Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1’s Cosmetic Benefits/Uses

Formulators turn to this peptide because it fills several helpful roles at once.

  • Hair conditioning – coats the hair shaft with a thin protein layer that smooths rough cuticles, boosts softness and makes strands easier to comb
  • Skin conditioning – helps skin feel softer and look healthier by supporting its natural barrier and adding a touch of suppleness
  • Emollient – provides a light, silky feel that reduces dryness and leaves both skin and hair more comfortable
  • Skin protecting – forms a breathable shield that defends against everyday aggressors like wind or pollution which can lead to redness or tightness

Who Can Use Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1

This peptide is generally well tolerated by all skin types including oily, dry and combination because it is lightweight and non occlusive. Sensitive skin can usually handle it too thanks to its soothing profile, though anyone prone to protein sensitivities should watch for reactions.

Because the molecule is made in microbes rather than harvested directly from fish, it is suitable for vegetarians. Strict vegans may still hesitate since the original genetic blueprint comes from an animal source, so personal ethics will decide.

No specific warnings exist for pregnancy or breastfeeding, and there is no evidence the peptide penetrates deeply enough to affect the fetus or milk supply. This is not medical advice; expectant or nursing individuals should show any new product to their doctor first.

The ingredient does not increase photosensitivity, so it will not make skin more prone to sunburn. It also plays well with most other common actives and works year round.

Potential Side Effects/Adverse Reactions

Reactions to topical Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1 differ from person to person. The effects listed below are possible, not probable, and most users will enjoy the ingredient without any trouble if the finished product is formulated correctly.

  • Mild redness or warmth on very sensitive skin
  • Itching or tingling when applied to broken or freshly exfoliated areas
  • Allergic response in people with fish protein allergy despite the fermentation process
  • Temporary scalp buildup or limp feel in fine hair if too much product is left on
  • Extra dryness when layered with strong exfoliating acids or high strength retinoids

If any of these issues appear stop using the product and seek guidance from a qualified healthcare professional.

Comedogenic Rating

Rating: 0 / 5

Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1 is a large, water-soluble peptide that lacks heavy oils or waxes known to clog pores. It sits on the surface as a light protein film, then rinses or wears off without blocking sebaceous glands, so it earns a true zero on the comedogenic scale.

Suitable for acne-prone skin.

Because this peptide often appears in lightweight serums and lotions, the overall formula usually stays non-greasy, keeping breakouts at bay. Only if the finished product contains other pore-clogging ingredients would the risk increase.

Summary

Sr-Rainbow Trout Oligopeptide-1 Sh-Polypeptide-1 conditions hair, softens skin, works as a gentle emollient and lays down a protective protein shield. It does this by forming a thin breathable layer that smooths cuticles, reinforces the skin barrier and locks in moisture without heaviness.

The peptide is still a niche player compared to buzzier actives like hyaluronic acid or vitamin C yet formulators appreciate its multitasking nature so its presence is quietly growing in premium serums, masks and leave-in conditioners.

Safety profiles show very low irritation or sensitization rates. As with any new cosmetic ingredient it is smart to patch test a fresh product first to confirm personal compatibility.

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