Dear Colleagues,

Plant extracts have been used for medicinal purposes for centuries and continue to constitute an important area of research today. With advances in technology and analytical methods, plant compounds can be analysed with greater precision and efficiency than ever before. This has led to the discovery of new compounds with potential therapeutic benefits and to the development of a better understanding of the mechanisms behind the beneficial effects impaired by traditional herbal remedies. Among the key challenges in the extraction of plant compounds is the need to achieve a high yield of the desired compounds while minimizing the extraction of unwanted substances. The identification of phytochemical markers is important for ensuring the quality, safety, and efficacy of plant-based products and their extraction. This Special Issue aims to publish research on advances in the extraction and analysis techniques that can be applied to obtain a better understanding of the complex chemistry of plant extracts and their potential therapeutic benefits.

Prof. Dr. Lina Raudonė
Guest Editor

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• phytochemistry
• extraction
• profiles
• analytical markers
• chromatography
• plant extracts

Title: Sustainable Development through the Valorization of Grape Seed Oil By-Products: Evaluation of Stilbenoid and Polyphenol Content
Authors: Veronica D'Eusanio*, Andrea Marchetti, Lorenzo Tassi*
Affiliation: Affiliation of all authors: Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
Abstract: This scientific paper delves into the examination of de-fatted grape seeds, a byproduct stemming from grape seed oil production. The primary objective is to characterize the methanol extract of de-fatted grape seeds, with a specific focus on quantifying the concentrations of key stilbenoids, including resveratrol, piceatannol, and viniferin. Comparative analyses are conducted, evaluating stilbenoid levels in both de-fatted and untreated grape seeds. Furthermore, the study measures the total polyphenol content using the Folin method. In the context of sustainable development, this research underscores the importance of valorizing waste materials. By exploring the potential of de-fatted grape seeds, which are often overlooked residues of the oil extraction process, we not only contribute to a more comprehensive understanding of their chemical composition but also highlight the prospect of utilizing these byproducts for various applications

Title: *AHPND
Authors: Dr. Ahmed Al-Kawmani
Affiliation: Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
Abstract: *AHPND is a bacterial disease that affects the shrimp industry worldwide. The causative agent of this disease is /Vibrio parahaemolyticus/ which infects shrimp’s gut and secretes hemolysin toxin which causes necrotic changes in hepatopancreas cells. AHPND and Retinoid metabolism have been linked together on the molecular level of Retinol and Retinoic acid. Retinol Dehydrogenase 12 (RDH12) is an Oxidoreductase enzyme that converts Retinol into Retinal by oxidative reaction. In addition to that, RDH12 is also responsible for the conversion of all-trans retinaldehyde to all-trans retinol which acts as bacterial DNA immune receptor. A-trans-retinol 13,14-reductase) AT-R 13,14-R (is a recently discovered enzyme of the SDR superfamily that is believed to play a role in Retinoids metabolism. In this study, we aim to measure the gene expression of RDH12 and AT-R 13,14-R enzymes during AHPND infection at different points after infection. We found that during this disease, RDH12 is upregulated 6-fold compared with the control group. Moreover, AT-R 13,14-R has shown a 9-fold downregulation in the infected group of shrimps. These results indicate Retinoid signaling pathway disruption during AHPND that is hypothesized to restore normal Retinoid signaling and reduce the cytotoxicity effect of certain toxic molecules and reactive oxygen species. The rho-ROCK pathway seems to play a critical role in AHPND pathogenesis. *Keywords: *AHPND; RDH12, Retinol, ATR-R-12,14-R