Ingredient Science

Unlocking ingredient potential through fermentation.

Starting with Golden Cocoon, we develop Leusilk™, our proprietary cosmetic ingredient, through fermentation. Its development is supported by research data and patented technology.

Golden Cocoon beside glass vessels used to illustrate ingredient research
01 · Golden Cocoon

The amino acid connection.

Golden Cocoon drew our attention as a natural source of silk proteins composed of diverse amino acids. Amino acids are also key components of the skin’s Natural Moisturizing Factor (NMF) and contribute to moisture retention.

This connection led us to explore Golden Cocoon as the starting material for our fermentation-based cosmetic ingredient research.

02 · Fermentation technology

Fermentation at the core of ingredient development.

Fermentation is central to our ingredient development. Using Golden Cocoon as the starting material, we develop Leusilk™, our proprietary cosmetic ingredient for skincare formulations.

01

Golden Cocoon

Natural Starting Material

Selected for its silk proteins composed of diverse amino acids.

02

Fermentation

Core Technology

Central to the way we develop our proprietary cosmetic ingredient.

03

Leusilk™

Proprietary Cosmetic Ingredient

Developed from Golden Cocoon through our fermentation-based approach.

03 · Proprietary cosmetic ingredient

Leusilk™

A proprietary fermented cosmetic ingredient derived from Golden Cocoon and developed for skincare formulations.

Trade NameLeusilk™
INCI NameLeuconostoc/Silkworm Cocoon Extract Ferment Filtrate
Japanese Labeling Nameレウコノストック/カイコまゆエキス発酵液
Starting MaterialGolden Cocoon
TechnologyFermentation
04 · Research

The data behind Leusilk™

We characterize Leusilk™ through analytical testing and selected in vitro studies, with results presented alongside relevant test conditions.

Analytical testing

Amino Acid
Analysis

Compared with Cocoon Extract (CE)

Free amino acid analysis showed higher levels in Leusilk™ than in Cocoon Extract (CE).

CE (Cocoon Extract)Leusilk™

Total Free
Amino Acids

322×

Beauty-Related
Amino Acids

148×

NMF-Related
Amino Acids

204×
In vitro assay

Cell Viability

152%Viability at
100 µg/mL

At 100 μg/mL, Leusilk™ showed 152% viability compared with 116% for Cocoon Extract (CE).

HDF (Human Dermal Fibroblast)

In vitro assay

Wound Healing

69%Recovery
at 12h

At 12 h, Leusilk™ reached 69% recovery, compared with 61% for Cocoon Extract (CE) and 52% for control.

In vitro assay

Collagenase Inhibition

77%Inhibition at
1,000 µg/mL

Leusilk™ showed concentration-dependent collagenase inhibition across the tested range.

05 · PATENT & INGREDIENT NOMENCLATURE

From proprietary technology to established ingredient identity.

Our proprietary technology is protected by a registered patent. Leusilk™ also has an INCI name and a Japanese labeling name.

Patent registration certificate with the company address redacted.

Registered Patent

Excerpt of the INCI name assignment record for Leuconostoc/Silkworm Cocoon Extract Ferment Filtrate.

Originally filed under the former trade name FT-CLCM.
Current trade name: Leusilk™.

INCI Name Assignment

Japanese labeling name notice with the representative name and receipt number redacted.

Japanese Labeling Name Assignment

Document excerpts are presented from source records with personal and third-party information redacted.

Product partnership

Turning ingredient innovation into cosmetic products.

We welcome inquiries about our cosmetic products and international distribution partnerships.