This study aimed to characterize and investigate the potential of the oils from Gryllus bimaculatus, Teleogryllus mitratus, and Acheta domesticus to be used in nanoemulsions. The oils were extracted by a cold press method and characterized for their fatty acid profiles. Their irritation effects on the chorioallantoic membrane (CAM) were evaluated, along with investigations of solubility and the required hydrophilic–lipophilic balance (RHLB). Various parameters impacting nanoemulsion generation using high-pressure homogenization were investigated. The findings revealed that G. bimaculatus yielded the highest oil content (24.58% w/w), followed by T. mitratus (20.96% w/w) and A. domesticus (15.46% w/w). Their major fatty acids were palmitic, oleic, and linoleic acids. All oils showed no irritation, suggesting safety for topical use. The RHLB values of each oil were around six–seven. However, they could be successfully developed into nanoemulsions using various surfactants. All cricket oils could be used for the nanoemulsion preparation, but T. mitratus yielded the smallest internal droplet size with acceptable PDI and zeta potential. Nanoemulsion was found to significantly enhance the antioxidant and anti-skin wrinkle of the T. mitratus oil. These findings pointed to the possible use of cricket oils in nanoemulsions, which could be used in various applications, including topical and cosmetic formulations.

This study aimed to assess natural oils for their antioxidant and anti-hyaluronidase properties and select the most effective candidate for development into nanoemulsions (NE) for clinical evaluations. The oils were assessed using 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS^•+) and ferric thiocyanate assays for antioxidant properties and an enzyme-substrate reaction assay for anti-hyaluronidase activity. The most potent oil was formulated into conventional emulsions (CE) and NE, which were characterized and evaluated for their stability, both in accelerated and long-term conditions. The irritation potential was assessed using both the hen’s eggs chorioallantoic membrane test and a clinical trial. Skin hydration enhancement and skin wrinkle reduction efficacy were clinically assessed. Macadamia integrifolia oil exhibited significant potency as an ABTS^•+ radical scavenger, lipid peroxidation inhibitor, and hyaluronidase inhibitor (p < 0.05). Both the CE and NE, comprising 15% w/w oil, 5% w/w Tween^® 80 and Span^® 80, and 80% w/w DI water, were found to be optimal. NE with an internal droplet size of 112.4 ± 0.8 nm, polydispersity index of 0.17 ± 0.01, and zeta potential of −31.5 ± 1.0 mV, had good stability and induced no irritation. Both CE and NE enhanced skin hydration and reduced skin wrinkles in human volunteers, while NE was outstanding in skin hydration enhancement.

Background: Silkworm cocoons are rich in bioactive compounds beneficial for cosmetic applications. This study presented a novel approach by comparing microwave and ultrasonic pretreatments to enhance silk protein extraction efficiency. The aim was to evaluate the effects of pretreatment methods and extraction solvents on the bioactive components, physicochemical properties, and biological activities of silkworm cocoon extracts for cosmetic applications. Methods: Cocoons of Bombyx mori (Nang Lai) were pretreated using conventional soaking (12 h), microwave (3 min), or ultrasonication (30 min), and then subjected to aqueous or enzymatic extraction. The extracts were analyzed for protein, phenolic, and flavonoid content. Structural and thermal properties were characterized using infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. Antioxidant and anti-aging properties were assessed by measuring the inhibition of nitric oxide, 2,2-diphenyl-1-picrylhydrazyl (DPPH^•), and collagenase. Skin moisturizing effects and irritation potential were tested. Results: Silkworm cocoons pretreated with microwave (ALM) and ultrasonication (ALS), followed by enzymatic extraction, had the highest yields (21.6 ± 0.5% and 21.7 ± 0.4%, respectively). Despite their slightly lower protein contents, these extracts showed elevated phenolic and flavonoid content. ALM and ALS demonstrated strong antioxidant activities, with DPPH^• scavenging of 65.9 ± 0.2% and 65.2 ± 0.3%, collagenase inhibition of 60.3 ± 0.8% and 59.7 ± 1.7%, and nitric oxide inhibition of 13.5 ± 0.4% and 12.9 ± 0.2%, respectively. Skin moisturizing effects increased by 63.6 ± 2.1% for ALM and 61.2 ± 1.5% for ALS, compared to 1.3 ± 0.6% in the control. All extracts were found to be non-irritating for topical application, indicating their safety for skincare formulations. Conclusions: Microwave and ultrasonication pretreatments, in combination with enzymatic extraction, provide an effective, time-efficient, and sustainable method for producing silkworm cocoon extracts with promising cosmetic applications.