Potent nanoemulsions: Unlocking anti-aging and hydrating benefits from passion fruit, lavender and tapioca

10 May 2024 --- Advancements combining natural solutions with nanotechnology are driving research for improved delivery of active ingredients and stable product formulations. Three new papers present nanoemulsions: One looks at anti-aging elements from Passiflora quadrangularis, another creates a natural polymeric material mask, while the third encapsulates lavender essential oil.

According to the research papers, nanoemulsions are characterized by their stability and enhanced absorption capabilities. They facilitate the interaction of active ingredients with the skin to combat skin issues against dry skin and environmental stressors.

Nanoemulsion for anti-aging
The first study in Cosmetics investigates the anti-aging qualities of fruit extracts from Passiflora quadrangularis, a type of passion fruit known as giant granadilla, for cosmetics applications.

Gallic acid emerged as a standout compound from giant granadilla.The researchers found that extracts from various parts of the passion fruit, including the skin (epicarp), flesh (mesocarp), inner layer (endocarp) and seeds, showed strong activity against enzymes that break down collagen (anti-collagenase), elastin (anti-elastase) and hyaluronic acid (anti-hyaluronidase). These extracts produced high-yields and “excellent” results.

The endocarp and seed extracts showed noteworthy inhibition effects on skin aging-related enzymes. Gallic acid emerged as a standout compound, showing high concentrations in endocarp extract (1,449.35 mg/g extract) followed by the seed extract (839.63 mg gallic acid/g extract).

The researchers developed stable nanoemulsions containing endocarp and seed extracts to harness the benefits for cosmetic applications. 

Due to their small particle sizes and increased stability, the nanoemulsions are noted to support efficient skin care product delivery.

The researchers used ultrasonication to produce nanoemulsions with small particle sizes. These emulsions have a uniform size distribution (low polydispersity index) and an electrical charge (“favorable” zeta potential). Separate studies involving human volunteers confirmed the nanoemulsions’ effects and safety. 

Participants saw improvements in skin hydration and a decrease in wrinkles after applying the product for 60 days, indicating the potential use of Passiflora quadrangularis fruit extract to address skin aging issues.

“The nano-serum-containing extracts improved skin hydration and reduced the depth of wrinkles. Additionally, 70% of the volunteers expressed satisfaction with the product,” detail the authors.

Biofilms boost nanoemulsion delivery
The second research paper, “Preparation and Characterization of a Topical Delivery System for Nanoemulsions Using a Composite Film of Pectin and Tapioca,” highlights a skin-compatible way to better deliver nanoemulsions. 

Bioactive films support industry trends toward environmentally friendly and sustainable solutions.The research explores using natural polymeric material masks, specifically pectin and tapioca starch-based films, as carriers for nanoemulsions. 

The authors suggest that these bioactive films support industry trends toward environmentally friendly and sustainable solutions by providing skin compatibility, biocompatibility and biodegradability.

The researchers also found films made with a specific concentration of tapioca starch showed optimal occlusive effects, enhancing the skin’s absorption of nanoemulsions. 

Moreover, the type of plasticizer used influenced the overall properties of the standard emulsion film, showing the importance of ingredient selection.

“The oil phase used for the preparation of the nanoemulsion was rice bran oil (supplied by Campestre) and surfactants Sorbitan Monooleate (supplied by Croda) and PEG-30 castor oil (supplied by Oxiteno),” details the paper.

“For the preparation of the films, low molecular pectin (by CP Kelco) was used as a film formation polymer; tapioca starch (by Upchef) was used as a rheological modifier. Glycerin and propylene glycol (supplied by Synth) were used as plasticizers and calcium chloride (supplied by Cinetica Química) as a crosslinking agent.”

The study explored ways to optimize the film’s formulation to ensure the “structural integrity, flexibility and occlusive effects” necessary for delivering active ingredients to the skin. They include adjusting the plasticizer concentration and calcium chloride crosslinking.

Natural oil in nanoemulsions
A separate study in Cosmetics integrates lavender essential oil, known for its soothing properties, into a nanoemulsion for skin care to optimize carrier systems for stability and release kinetics. 

NELs showed better skin hydration and accelerated barrier repair compared to CELs.The study compared conventional emulsions and nanoemulsions with and without lavender essential oil incorporation (CELs and NELs) to evaluate their physicochemical properties, stability and lavender essential oil retention. 

“Essential oils are complex mixtures of a large number of volatile plant secondary metabolites and are widely used in cosmetic and pharmaceutical products,” write the authors.

Compared to conventional emulsions, nanoemulsions exhibited “superior” stability and retention of lavender essential oil, indicating they act as better carrier systems. The researchers underscore the importance of the finding for skin care formulations that must deliver active ingredients stably and efficiently.

The researchers found that CELs and NELs released the components of the lavender essential oil gradually (via a diffusion-based mechanism). The nanoemulsions provided a more sustained release, meaning the beneficial effects lasted longer. This controlled release is key to ensuring the product’s effectiveness over a longer period for an improved user experience.

Moreover, NELs showed better skin hydration and accelerated barrier repair compared to CELs, pointing to the potential for hydrating and barrier-enhancing skin care.

“These findings contribute to understanding the carrier system effects on LEO delivery and underscore NE as a promising vehicle for skin care applications. Further research should explore underlying mechanisms and conduct long-term safety and efficacy studies to fully exploit the therapeutic potential of NE in dermatological applications,” suggest the authors.

In other research on cosmetic nanoemulsions, researchers from Thailand explored the potential of velvet bean seed extract. 

By Venya Patel