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Ecklonia cava and its major compound dieckol, both natural marine products, possess antioxidant, anti-inflammatory, and metabolic-regulating effects. Zika virus (ZIKV), an arbovirus from the Flaviviridae family, is transmitted by mosquitoes and causes serious illnesses in humans. This study aimed to evaluate the anti-ZIKV potential of Ecklonia cava and dieckol. The antiviral activity of Ecklonia cava extract (ECE), prepared with 80% ethanol, was assessed in ZIKV-infected Vero E6 cells through MTT assay, plaque assay, and quantitative polymerase chain reaction (qPCR), demonstrating no cytotoxicity and a significant reduction in viral titers and ZIKV mRNA levels. In addition, ECE decreased the expression of tumor necrosis factor-α and interferon-induced protein with tetratricopeptide repeats in the ZIKV-infected cells. Dieckol, the primary active compound in ECE, exhibited potent anti-ZIKV activity, with a half maximal inhibitory concentration (IC50), value of 4.8 µM. In silico molecular docking analysis revealed that dieckol forms stable complexes with key ZIKV proteins, including the envelope, NS2B/NS3, and RNA-dependent RNA polymerase (RdRp) protein, exhibiting high binding energies of −438.09 kcal/mol, −1040.51 kcal/mol, and −1043.40 kcal/mol, respectively. Overall, our findings suggest that ECE and dieckol are promising candidates for the development of anti-ZIKV agents. [ABSTRACT FROM AUTHOR]

Haliotis discus, an abalone, is a marine gastropod mollusk that has been cultivated globally owing to its nutritional value and high market demand. However, the visceral parts of H. discus are typically discarded as by-products, highlighting the need to explore their potential value in developing cosmeceuticals and pharmaceuticals. This study investigated the potential moisturizing effects of H. discus visceral tissues. Various hydrolysates from H. discus viscera tissue were evaluated for proximate composition, radical scavenging, and hyaluronidase inhibition activities. Alcalase hydrolysate was isolated using gel filtration chromatography (GFC), and its moisturizing effects were tested on human dermal fibroblasts (HDF), HaCaT keratinocytes, and reconstructed human skin tissue. The Alcalase hydrolysate showed the highest extraction yield, radical scavenging, and hyaluronidase inhibition activities. The Alcalase hydrolysate GFC fraction 1 increased collagen synthesis-related molecules, including procollagen type 1 in HDF and hyaluronic acid-related molecules in HaCaT cells. These moisturizing effects were confirmed in reconstructed human skin tissues by increased levels of aquaporin 3 and filaggrin. Fraction 1 consisted of two main peptides: DNPLLPGPPF and SADNPLLPGPPF. In conclusion, H. discus Alcalase hydrolysate and its fractions have potential moisturizing properties and can be used as cosmeceuticals. [ABSTRACT FROM AUTHOR]

Abalone is a rich source of nutrition, the viscera of which are discarded as by-product during processing. This study explored the biological activities of peptides derived from abalone viscera (AV). Trypsin-hydrolysate of AV (TAV) was purified into three fractions using a Sephadex G-10 column. Nine bioactive peptides (VAR, NYER, LGPY, VTPGLQY, QFPVGR, LGEW, QLQFPVGR, LDW, and NLGEW) derived from TAV-F2 were sequenced. LGPY, VTPGLQY, LGEW, LDW, and NLGEW exhibited antioxidant properties, with IC50 values of 0.213, 0.297, 0.289, 0.363, and 0.303 mg/mL, respectively. In vitro analysis determined that the peptides VAR, NYER, VTPGLQY, QFPVGR, LGEW, QLQFPVGR, and NLGEW inhibited ACE, with IC50 values of 0.104, 0.107, 0.023, 0.023, 0.165, 0.004, and 0.146 mg/mL, respectively. The binding interactions of ACE-bioactive peptide complexes were investigated using docking analysis with the ZDCOK server. VTPGLQT interacted with HIS513 and TYR523, and QLQFPVGR interacted with HIS353, ALA354, GLU384, HIS513, and TYR523, contributing to the inhibition of ACE activity. They also interacted with amino acids that contribute to stability by binding to zinc ions. QFPVGR may form complexes with ACE surface sites, suggesting indirect inhibition. These results indicate that AV is a potential source of bioactive peptides with dual antioxidant and anti-hypertensive dual effects. [ABSTRACT FROM AUTHOR]

Abalone, a marine edible gastropod with nutritional value, is a popular seafood delicacy worldwide, especially in Asia; however, viscera by-products are generally discarded during processing. Therefore, we investigated the skin health benefits of abalone viscera ultrasonic extract (AVU) in human dermal fibroblasts (HDFs) and human keratinocyte (HaCaT) cells. AVU showed valuable protein contents, indicating that it is a worthy and safe material for industrial application. AVU increased collagen synthesis production and messenger RNA (mRNA) expression of Collagen Type I Alpha 1, 2, and 3 chains through the transforming growth factor beta/suppressor of mother against the decapentaplegic pathway in HDF cells. AVU also increased hyaluronic acid production, upregulated Hyaluronan Synthases 1, 2, and 3, filaggrin and aquaporin3 mRNA levels, and downregulated hyaluronidase mRNA levels in HaCaT cells. Furthermore, mechanistic studies showed that AVU increased the phosphorylation of extracellular signal-regulated kinase, p38, and cyclic AMP response-binding protein activation. AVU activated the transcription factors, phosphoinositide 3-kinase, protein kinase B, and nuclear factor kappa B cell p65 and downregulated the degranulation of inhibitory kappa B in HaCaT cells. Studies of hyaluronic acid production in AVU by inhibiting EKR, p38 and NF-κB have shown that p38 MAPK and NF-κB signaling are pivotal mechanisms, particularly in the AVU. These results demonstrated that AVU produced from by-products may improve skin health and may thus be used as a functional food and cosmetics ingredient. [ABSTRACT FROM AUTHOR]

Recent advancements in the large-scale cultivation of Tetraselmis sp. in Korea have enabled year-round production of this marine microalgae. This study explores the potential industrial applications of Tetraselmis sp. biomass by investigating the antiviral properties of its extracts and primary components. The antiviral effects of Tetraselmis sp. extracts were evaluated in Zika virus (ZIKV)-infected cells. Following extensive isolation and purification, the main compounds were characterized using liquid chromatography–mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) analyses. Their antiviral activities were confirmed using in vitro and in silico tests. Tetraselmis sp. extracts reduced infectious viral particles and non-structural protein 1 messenger RNA levels in ZIKV-infected cells without inducing cytotoxicity. Additionally, they modulated the interferon-mediated immune system responses. Tetraselmis sp. extracts are composed of four main chlorophylls: chlorophyll a, chlorin e6-131-152-dimethyl-173-phytyl ester, hydroxychlorophyll a, and hydroxypheophytin a. Among them, chlorophyll a, chlorin e6-131-152-dimethyl-173-phytyl ester, and hydroxypheophytin showed the antiviral activities in ZIKV-infected cells and molecular docking simulations predicted interactions between these chlorophylls and ZIKV. Our findings suggest that Tetraselmis sp. chlorophyll extracts exert antiviral effects against ZIKV and could serve as potential therapeutic candidates against ZIKV infection. [ABSTRACT FROM AUTHOR]