Edible insects, specifically crickets, have emerged as sustainable and nutrient-dense alternatives to traditional livestock, offering high protein content and various bioactive peptides with antioxidant and anti-inflammatory properties. Despite their promise as natural cosmetic ingredients for skin-brightening and anti-aging, the direct use of crude cricket extracts is severely limited by poor skin penetration and the low stability of their bioactive proteins. To address these barriers, nanoemulsion-based delivery systems were considered a potential solution. These lipid-based formulations were chosen because their nanoscale droplet size increases surface area for better absorption and provides a protective environment that stabilizes sensitive proteins while facilitating localized delivery into the skin layers without systemic absorption.
Methods
The researchers freeze-dried and defatted Teleogryllus mitratus crickets, utilizing Subtilisin A-assisted extraction to obtain bioactive protein extracts (TMS). This extract was incorporated into an oil-in-water nanoemulsion through high-pressure homogenization using cricket oil and surfactants. The system was then characterized for droplet size, stability, and entrapment efficiency. Finally, in vitro release and skin retention studies were performed using Strat-M® membrane models.
Key Findings
- Superior Bioactivity: The Subtilisin A-assisted extract (TMS) yielded the highest protein content (76.0%) and demonstrated potent inhibitory effects against tyrosinase (for brightening) and hyaluronidase (for anti-aging).
- Physical Stability: The resulting nanoemulsion maintained a nanoscale droplet size (~288 nm) and a high negative zeta potential (< −30 mV), indicating strong colloidal stability and uniform distribution.
- Controlled Release: Compared to an aqueous solution, the nanoemulsion provided a slower and more sustained release of the extract, which is ideal for prolonged skin contact.
- Enhanced Skin Retention: The nanoemulsion significantly increased the localization of the extract within the skin membrane (3.8 µg/cm²), while preventing any detectable systemic permeation.
- Safety Profile: All cricket extracts and the final nanoemulsion formulation were found to be non-irritating in safety assessments.
The novelty of this research lies in being the first to explore the delivery of Teleogryllus mitratusproteins through a specialized nanoemulsion system to maximize dermatological benefits. By successfully overcoming the stability and penetration issues inherent in crude insect extracts, this study establishes a sustainable, high-performance framework for natural cosmeceuticals. The future implications of this work suggest that cricket-derived bioactive peptides could become standardized, eco-friendly ingredients in multifunctional products aimed at hydration, brightening, and anti-aging.
Link to the study: https://www.sciencedirect.com/science/article/pii/S2590156726000629
