Due to the sustainable organic matter bioconversion process used as substrate for its development, the Hermetia illucens (Linnaeus) larvae biomass is considered a source of compounds with high aggregate value and quite a promising market. The materials that can be extracted from H. illucens larvae have opened the door to a diverse new field of ingredients, mainly for the feed and food industry, but also with potential applicability in cosmetics. In this review we succinctly describe the larval development and rearing cycle, the main compounds identified from different types of extractions, their bioactivities and focus on possible applications in cosmetic products. A search was made in the databases PubMed, ScienceDirect and Web of Science with the terms ‘Hermetia illucens’, ‘bioactives’, ‘biochemical composition’ and ‘cosmetics ingredients’, which included 71 articles published since 1994.

There is an increasingly growing demand for the use of natural and sustainable bioactives in the field of the pharmaceutical and cosmetic industries. The biomass from black soldier fly larvae (Hermetia illucens) can be viewed as an innovative source of compounds with high aggregate value and marketing potential due to the sustainable organic matter bioconversion process used as substrate for its development. This insect can be a source of lipid compounds with high added value, mainly due to its high content in fatty acids (FA) with potential applicability in the pharmaceutical and cosmetic industry. In this context, in this work different extraction methods were tested (decoction, microwaves, maceration and ultrasound), using water, acetone, n-hexane as extraction solvents, to evaluate yields of the BSF larvae lipid extracts, as well as their lipid profile, and a preliminary safety screening was conducted. Results show that despite using different extraction techniques and solvents, similar FA composition profiles were obtained. The lauric acid content (C12: 0) is elevated in all the extracts in relation to the other FA, ranging 37%–62%. The contents in palmitic (C16: 0) and oleic (C18: 1n-9) acids, were also high in all applied extraction methods. The omega-6 FA (ω-6 PUFAs), mainly linoleic acid (C18: 2n6c), were also identified in the lipid fraction of BSF larvae biomass, with a content variation between 4.5% and 17.7%, while the omega-3 group, namely α-Linolenic acid (C18: 3n3), presented values between 0.66% and 1.95%. None of the extracts presented toxicity in preliminary tests with the Artemia salina model. Through this study, it was possible to confirm that BSF larvae oil can be obtained by sustainable methods, containing a broad mixture of FA and being highly rich in lauric acid, with a promising skin care applicability.

The current mindset in the cosmetics market about sustainable ingredients had increased the search for new sources of natural active ingredients. Cyanobacteria are a great source of functional ingredients for cosmetics, as a producer of pigments with described bioactive potential (carotenoids and phycobiliproteins). This work aimed to evaluate the cosmetic potential of marine cyanobacterium Cyanobium sp. pigment-targeted extracts (carotenoids and phycobiliproteins), evaluating their in vitro safety through cytotoxicity assays, cosmetic-related enzyme inhibition, ingredient stability, and putative product (serum formulation). Results showed no cytotoxicity from the extracts in skin-related cell lines. Carotenoid extract showed anti-hyaluronidase capacity (IC₅₀ = 108.74 ± 5.74 mg mL⁻¹) and phycobiliprotein extract showed anti-hyaluronidase and anti-collagenase capacity (IC₅₀ = 67.25 ± 1.18 and 582.82 ± 56.99 mg mL⁻¹, respectively). Regarding ingredient and serum stability, both ingredients showed higher stability at low-temperature conditions, and it was possible to maintain the pigment content and bioactive capacity stable during the tested period, although in higher temperatures the product was degraded in a week. As a major conclusion, both extracts can be potential natural and sustainable ingredients for cosmetic uses, with relatively simple formulation and storage, and can be promising natural anti-aging ingredients due to their bioactive capacity.

The human epidermis has a characteristic lipidic composition in the stratum corneum, where ceramides play a crucial role in the skin barrier homeostasis and in water-holding capacity. Several skin diseases, such as atopic dermatitis and psoriasis, exhibit a dysfunction in the lipid barrier with altered ceramide levels and increased loss of transepidermal water. Glucocorticoids are normally employed in the therapeutical management of these pathologies. However, they have shown a poor safety profile and reduced treatment efficiency. The main objective of this review is to, within the framework of the limitations of the currently available therapeutical approaches, establish the relevance of nanocarriers as a safe and efficient delivery strategy for glucocorticoids and ceramides in the topical treatment of skin disorders with barrier impairment.

The outermost layer of the epidermis, the stratum corneum (SC), ensures protection against harmful xenobiotics, and alterations in its lipidic matrix composition are related to several cutaneous dysfunctions. The skin barrier function is usually attributed to ceramides, but the role of free fatty acids, such as stearic acid, has been increasingly acknowledged. This research work aimed to develop solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) based on stearic acid and glyceryl distearate, in order to explore the potential of these materials as the basis of lipid nanoparticles. Different blends of stearic acid, Precirol^® ATO 5, Capryol^® 90 and Tween^® 80 were probed to prepare SLN and NLC. These lipid nanoparticles were further characterised according to particle size, polydispersity index (PDI), pH, and viscosity. Accelerated and long-term stability tests were also performed for 90 days, as well as in vivo assays to evaluate safety and efficacy. Overall, most nanoparticles showed interesting properties for topical application if they had sizes less than 300 nm, PDI below 0.3, pH compatible with skin and viscosity lower than 5 mPa.s. In long-term stability studies, the SLN_2 and NLC_2 formulations stood out, as they remained stable over time. In vivo biocompatibility tests conducted in human volunteers showed no negative impact of the formulations when applied openly or under occlusion. Efficacy studies with the most stable nanoparticles made of Precirol^® ATO 5 showed an increase in skin hydration. The nanoparticles developed in this study have shown potential to be used for cosmetic purposes, and the blend of lipids provided good biocompatibility and moisturising properties.