Au-NP-Decorated Cotton Swabs as a Facile SERS Substrate for Food-Safety-Related Molecule Detection.

Recently, food safety has received considerable attention, and various analytical techniques have been employed to monitor food quality. One of the promising techniques in this domain is the surface-enhanced Raman scattering (SERS) technique. This study developed a facile, cost-effective SERS method by supporting a wipe-type substrate with a small-head cotton swab. We fabricated Au-nanoparticle (NP)-decorated cotton swabs (CS-Au NP) via the dropwise addition of gold colloid on the cotton fibers. These swabs exhibit reduced gold colloid consumption and a compact fiber structure, allowing for the uniform distribution of Au NPs and easy capture of molecular signals. Experiments were conducted to obtain a CS-Au NP wiper performance optimized for cotton swab selection, NaCl concentration, and Au NP layers. The Raman reporter molecule 4-mercaptopyridine was detected at a concentration of 1 × 10-8 M and a relative standard deviation of ≤10%. The proposed SERS platform enables the facile and reliable detection of food-safety-related molecules such as malachite green on the surface of fruits and vegetables. This paper describes the development of an easy, cost-effective, and environment-friendly method of detecting food-safety-related molecules on various food surfaces through SERS.

Zanthoxylum bungeanum essential oil induces apoptosis of HaCaT human keratinocytes.

ETHNOPHARMACOLOGICAL RELEVANCE: Zanthoxylum bungeanum (ZB), a Chinese herb medicine, has been shown to possess a wide range of biological activities including anti-tumor, anti-inflammatory, and anti-microbial activity and has long been used to treat a variety of skin diseases including psoriasis. However, the underlying mechanism of action has not been systematically elucidated. AIM OF THE STUDY: to analyze the chemical composition of the hydro-distilled Zanthoxylum bungeanum essential oil (ZBEO), and to investigate its anti-proliferative activity on HaCaT cells as well as the underlying anti-psoriasis mechanisms. MATERIALS AND METHODS: The chemical composition of ZBEO was analyzed with gas chromatography coupled to mass spectrometry (GC-MS). HaCaT cells was exposed to different dose of ZBEO added in medium prior to morphologic features analysis as well as cell cycle arrest examination with Flow cytometry. Western blot analysis was employed to estimate the expression level of proteins including caspase-8/9/3, PARP, Bax and Bcl-2. RESULTS: Thirty-nine compounds of the ZBEO were identified GC-MS. ZBEO-treated HaCaT cells showed typical apoptotic morphologic features by DAPI staining assay. The ZBEO significantly inhibited proliferation of HaCaT cells in a dose- and time-dependent manner and induced S phase arrest apoptosis in HaCaT cells. Furthermore, western blot analysis revealed that the ZBEO increased expression of cleaved caspase-8/9/3, PARP, and Bax, decreased Bcl-2 levels. CONCLUSION: ZBEO inhibits the proliferation of HaCaT cells, resulting from the induction of cellular apoptosis through both intrinsic and extrinsic pathways. ZBEO is a potential candidate that may be considered for development into an anti-psoriasis drug.

Bitter apricot essential oil induces apoptosis of human HaCaT keratinocytes.

Psoriasis is a chronic skin disease that affects approximately 2% of the world's population. Conventional therapeutic approaches are not effective or necessarily safe for treating symptoms due to the serious side effects and resistance to currently prescribed drugs. Traditionally, in oriental medicine, apricot seed (Semen Armeniacae amarum) is used to treat skin diseases. However, the underlying mechanism of action has not been systematically elucidated. In the present study, the anti-proliferative effect of bitter apricot essential oil (BAEO) on cultured HaCaT cells was evaluated and the mechanism of action investigated. BAEO was isolated by hydrodistillation, and gas chromatography-mass spectrometry (GC-MS) analysis identified benzaldehyde (75.35%), benzoic acid (6.21%) and mandelonitrile (5.38%). HaCaT cell growth, measured by sulforhodamine B assay (SRB), was inhibited by BAEO with an IC50 value of 142.45 µg/ml. Apoptosis of HaCaT cells treated with BAEO was detected by cell cycle, flow cytometry, and western blot analyses. These measurements revealed G0/G1 cell cycle arrest, elevated numbers of early and late stage apoptotic cells, and caspases-3/8/9 and PARP activation. Z-VAD-FMK, a broad-spectrum caspase inhibitor, attenuated BAEO-induced apoptosis. Also, increased Bax and decreased Bcl-2 levels suggest that BAEO-induced apoptosis is mediated through both death receptor and mitochondrial pathways. Moreover, reduced Rel/NF-κB levels suggest that BAEO-mediated apoptosis is also associated with inhibition of the NF-κB pathway. These data suggest that BAEO is a naturally occurring material that functions as a potent pro-apoptotic factor for human keratinocytes. Thus, it is a promising candidate to treat psoriasis.