Min Wang

The genus Citrus (Rutaceae) produces essential oils (EOs) widely utilized in food, pharmaceutical, cosmetic, and biomaterial industries due to their distinct organoleptic properties. These EOs are primarily composed of monoterpenes (e.g., limonene), sesquiterpene hydrocarbons, and oxygenated derivatives, which exhibit anti‐inflammatory, antioxidant, antibacterial, antineoplastic, and insecticidal activities. Principal extraction methods include cold pressing (CP), solvent extraction, distillation, ultrasound‐assisted extraction (UAE), microwave‐assisted extraction (MAE), and supercritical fluid extraction (SFE). Due to the increasing prevalence of adulteration and pesticide residues, robust analytical methods for their detection are required. This review addresses the major chemical components, common extraction techniques, and biological activities of Citrus EOs. Analytical approaches for identifying adulterants and pesticide residues are also examined. Particular attention is given to furocoumarin‐induced photosensitivity, a critical safety concern. Addressing these issues is essential to provide a scientific basis for the rational and expanded application of Citrus EOs in food science, material engineering, and related fields.

Skin is the first line of defence between the human body and the outside world, and it is constantly exposed to external injuries and wounds for a variety of reasons. Collagen is a structural protein of the extracellular matrix and an important component of the dermis. As a wound dressing, collagen not only provides nutrients to wounds but also enhances the immune response in the pre-healing phase, making it an excellent biomaterial for healing. In this study, we used electrospinning and freeze-drying technology to prepare a Bovine Achilles Tendon Collagen (BATC) electrospun composite membrane and a BATC freeze-dried composite membrane using BATC as a substrate supplemented with 16.7% Polyethylene oxide (PEO) and 0.2% Kukoamine B (KuB). The physicochemical properties and biocompatibility of the BATC composite membrane were verified via scanning electron microscopy, Fourier-transform infrared spectroscopy, and DSC analysis and by measuring the DPPH radical-scavenging capacity, water absorption, water retention, in vitro drug release, and extract cytotoxicity. The BATC composite membrane was found to have a significant effect on skin wound healing, especially in the middle stage of healing, in a mouse full-thickness skin injury model. The BATC/PEO/KuB electrospun composite membrane (EBPK) had the best capacity for promoting wound healing and can be used as a wound dressing for in-depth research and development, and KuB, a monomer component with a clear structure and mechanism of action, can be used as a candidate component of composite dressings.

The skin is the body’s largest organ. It serves various functions, including protection and metabolism. Due to its structure and location, it is more vulnerable to external physical and chemical damage than internal organs. Additionally, certain endogenous diseases can cause pathological changes to appear on the skin and nerves. When skin tissue breaks down or sustains severe trauma, the cells, blood vessels, and nerves across all layers can suffer varying degrees of damage. This often results in pain, itching, sensory disturbances, and other discomforts, causing significant distress to patients. Stem-cell-derived exosome therapy has emerged as a promising treatment for skin injuries due to its safety, non-toxicity, and precision medicine benefits. Research has shown that stem-cell-derived exosomes regulate nerve cells by mediating MicroRNA (miRNA) transport and expression between cells, promoting axon growth. This exosome-driven miRNA exchange serves as a vital mode of intercellular communication, playing a crucial role in nervous system repair. Nerves play a critical role in skin wound healing and tissue regeneration, with sensory and autonomic nerves influencing key skin functions such as inflammation, immune defense, apoptosis, proliferation, and wound repair. Exosomes may aid in treating cutaneous nerve injuries by directly or indirectly promoting axon regeneration, nerve cell proliferation, and the release of protective neurofactors.

Purpose: Chronic wounds that are difficult to heal pose a major challenge for clinicians and researchers. Currently, common treatment methods focus on isolating the wound from the outside world, relying on the tissue at the wound site to grow and heal unaided. Umbilical cord mesenchymal stem cell (MSC) exosomes can promote wound healing by enhancing new blood vessel growth at the wound site. Valproic acid (VPA) reduces the inflammatory response and acts on macrophages to accelerate wound closure. In this study, VPA was loaded into umbilical cord MSC exosomes to form a drug carrier exosome (VPA-EXO) with the aim of investigating the effect of VPA-EXO on wound healing. Methods: This study first isolated and obtained umbilical cord MSC exosomes, then added VPA to the exosomes and explored the ability of VPA-EXO to promote the proliferation and migration of human skin fibroblasts (HSFs) and human umbilical vein endothelial cells (HUVECs), as well as the ability to promote the angiogenesis of HUVECs, by using scratch, Transwell, and angiogenesis assays. An in vitro cell model was established and treated with VPA-EXO, and the expression levels of inflammation and pro-angiogenesis-related proteins and genes were examined using Western blot and qRT-PCR. The therapeutic effect of VPA-EXO on promoting wound healing in a whole skin wound model was investigated using image analysis of the wound site, H&E staining, and immunohistochemical staining experiments in a mouse wound model. Results: The in vitro model showed that VPA-EXO effectively promoted the proliferation and migration of human skin fibroblast cells and human umbilical vein endothelial cells; significantly inhibited the expression of MMP-9, IL-1β, IL-8, TNF-α, and PG-E2; and promoted the expression of vascular endothelial growth factors. In the mouse wound model, VPA-EXO reduced inflammation at the wound site, accelerated wound healing, and significantly increased the collagen content of tissue at the wound site. Conclusions: As a complex with dual efficacy in simultaneously promoting tissue regeneration and inhibiting inflammation, VPA-EXO has potential applications in tissue wound healing and vascular regeneration. In future studies, we will further investigate the mechanism of action and application scenarios of drug-loaded exosome complexes in different types of wound healing and vascular regeneration.

The scale of the cosmetic market is increasing every day. There are many safety risks to cosmetics, but they benefit people at the same time. The skin can become red, swollen, itchy, chronically toxic, and senescent due to the misuse of cosmetics, triggering skin injuries, with contact dermatitis being the most common. Therefore, there is an urgent need for a system that can scientifically and rationally detect the composition and perform a toxicological assessment of cosmetic products. Traditional detection methods rely on instrumentation and method selection, which are less sensitive and more complex to perform. Engineered skin tissue has emerged with the advent of tissue engineering technology as an emerging bioengineering technology. The ideal engineered skin tissue is the basis for building good in vitro structures and physiological functions in this field. This review introduces the existing cosmetic testing and toxicological evaluation methods, the current development status, and the types and characteristics of engineered skin tissue. The application of engineered skin tissue in the field of cosmetic composition detection and toxicological evaluation, as well as the different types of tissue engineering scaffold materials and three-dimensional (3D) organoid preparation approaches, is highlighted in this review to provide methods and ideas for constructing the next engineered skin tissue for cosmetic raw material component analysis and toxicological evaluation.

In this study, a colorimetric sensor was developed for the detection of organophosphorus pesticides (OPs) using a heterogeneous nanozyme with phosphatase-like activity. Herein, this heterogeneous nanozyme (Au-pCeO₂) was obtained by the modification of gold nanoparticles on porous cerium oxide nanorods, resulting in synergistic hydrolysis performance for OPs. Taking methyl parathion (MP) as the target pesticide, the catalytic performance and mechanism of Au-pCeO₂ were investigated. Based on the phosphatase-like Au-pCeO₂, a dual-mode colorimetric sensor for MP was put forward by the analysis of the hydrolysis product via a UV-visible spectrophotometer and a smartphone. Under optimum conditions, this dual-mode strategy can be used for the on-site analysis of MP with concentrations of 5 to 200 μM. Additionally, it can be applied for MP detection in pear and lettuce samples with recoveries ranging from 85.27% to 115.87% and relative standard deviations (RSDs) not exceeding 6.20%, which can provide a simple and convenient method for OP detection in agricultural products.

Carbendazim (CBZ) abuse can lead to pesticide residues, which may threaten the environment and human health. In this paper, a portable three-electrode sensor based on laser-induced graphene (LIG) was proposed for the electrochemical detection of CBZ. Compared with the traditional preparation method of graphene, LIG is prepared by exposing the polyimide film to a laser, which is easily produced and patterned. To enhance the sensitivity, platinum nanoparticles (PtNPs) were electrodeposited on the surface of LIG. Under optimal conditions, our prepared sensor (LIG/Pt) has a good linear relationship with CBZ concentration in the range of 1–40 μM, with a low detection limit of 0.67 μM. Further, the sensor shows good recovery rates for the detection of CBZ in wastewater, which provides a fast and reliable method for real-time analysis of CBZ residues in water samples.

Owing to the rapid development of the cosmetic industry, cosmetic safety has become the focus of consumers’ attention. However, in order to achieve the desired effects in the short term, the illegal addition of hormones in cosmetics has emerged frequently, which could induce skin problems and even skin cancer after long-term use. Therefore, it is of great significance to master the illegal addition in cosmetics and effectively detect the hormones that may exist in cosmetics. In this review, we analyze the illegally added hormone types, detection values, and cosmetic types, as well as discuss the hormone risks in cosmetics for human beings, according to the data in unqualified cosmetics in China from 2017 to 2022. Results showed that although the frequency of adding hormones in cosmetics has declined, hormones are still the main prohibited substances in illegal cosmetics, especially facial masks. Because of the complex composition and the low concentration of hormones in cosmetics, it is necessary to combine efficient sample preparation technology with instrumental analysis. In order to give the readers a comprehensive overview of hormone analytical technologies in cosmetics, we summarize the advanced sample preparation techniques and commonly used detection techniques of hormones in cosmetics in the last decade (2012–2022). We found that ultrasound-assisted extraction, solid phase extraction, and microextraction coupled with chromatographic analysis are still the most widely used analytical technologies for hormones in cosmetics. Through the investigation of market status, the summary of sample pretreatment and detection technologies, as well as the discussion of their development trends in the future, our purpose is to provide a reference for the supervision of illegal hormone residues in cosmetics.

Wound repair is a key step in the treatment of skin injury caused by burn, surgery, and trauma. Various stem cells have been proven to promote wound healing and skin regeneration as candidate seed cells. Therefore, exosomes derived from stem cells are emerging as a promising method for wound repair. However, the mechanism by which exosomes promote wound repair is still unclear. In this study, we reported that exosomes derived from umbilical cord mesenchymal stem cells (UC-MSCs) promote wound healing and skin regeneration by treating cutaneous nerve damage. The results revealed that UC-MSCs exosomes (UC-MSC-Exo) promote the growth and migration of dermal fibroblast cells. In in vitro culture, dermal fibroblasts could promote to nerve cells and secrete nerve growth factors when stimulated by exosomes. During the repair process UC-MSC-Exo accelerated the recruitment of fibroblasts at the site of trauma and significantly enhanced cutaneous nerve regeneration in vivo. Interestingly, it was found that UC-MSC-Exo could promote wound healing and skin regeneration by recruiting fibroblasts, stimulating them to secrete nerve growth factors (NGFs) and promoting skin nerve regeneration. Therefore, we concluded that UC-MSC-Exo promote cutaneous nerve repair, which may play an important role in wound repair and skin regeneration.