Abstract
Considering a growing demand for medicinal/cosmetic products with natural actives, this study focuses on the low-energy nanoemulsions (LE-NEs) prepared via the Phase inversion composition (PIC) method at room temperature as potential carriers for natural oil. Four different red raspberry seed oils (ROs) were tested, as follows: cold-pressed vs. CO2-extracted, organic vs. non-organic, refined vs. unrefined. The oil phase was optimized with Tocopheryl acetate and Isostearyl isostearate, while water phase was adjusted with either glycerol or an antioxidant hydro-glycolic extract. This study has used a combined approach to formulation development, employing both conventional methods (pseudo-ternary phase diagram − PTPD, electrical conductivity, particle size measurements, microscopical analysis, and rheological measurements) and the methods novel to this area, such as textural analysis and Raman spectroscopy. Raman spectroscopy has detected fine differences in chemical composition among ROs, and it detected the interactions within nanoemulsions. It was shown that the cold-pressed, unrefined, organic grade oil (RO2) with 6.62% saturated fatty acids and 92.25% unsaturated fatty acids, was optimal for the LE-NEs. Textural analysis confirmed the existence of cubic gel-like phase as a crucial step in the formation of stable RO2-loaded LE-NEs, with droplets in the narrow nano-range (125 to 135 nm; PDI ≤ 0.1). The DPPH test in methanol and ABTS in aqueous medium have revealed a synergistic free radical scavenging effect between lipophilic and hydrophilic antioxidants in LE-NEs. The nanoemulsion carrier has improved the biological effect of raw materials on HeLa cervical adenocarcinoma cells, while exhibiting good safety profile, as confirmed on MRC-5 normal human lung fibroblasts. Overall, this study has shown that low-energy nanoemulsions present very promising carriers for topical delivery of natural bioactives. Raman spectroscopy and textural analysis have proven to be a useful addition to the arsenal of methods used in the formulation and characterization of nanoemulsion systems.
Highlights
In the era of the growing popularity of natural consumer products berry fruits are recognized as important sources of vitamins, minerals, antioxidants, polyunsaturated fatty acids, anti-carcinogenic compounds, UV-protective phyto-pigments and fibers [1,2,3,4]
pseudo-ternary phase diagram (PTPD) study with different red raspberry seed oils
As it was previously pointed out [3,4,8], there are many specialty ingredients, those of natural origin, available in different grades, which is a challenging situation in the formulation/production of complex systems that rely on physicochemical compatibility of all ingredients, such as low-energy nanoemulsions (LE-NEs)
Summary
In the era of the growing popularity of natural consumer products berry fruits are recognized as important sources of vitamins, minerals, antioxidants, polyunsaturated fatty acids, anti-carcinogenic compounds, UV-protective phyto-pigments and fibers [1,2,3,4]. Hydro-glycolic extracts made from whole raspberry fruit contain fruit acids (citric, malic), sugars (fructose, inositol, sucrose) and antioxidants: tannins (polyphenols), vitamin C, and anthocyanins (red pigments) [6,7,8]. Another promising, but underresearched, raw material unexploited for topical application is French oak fruit (acorn) extract, a polyphenol-rich extract with the high antioxidant performance [9,10,11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
